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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. Comparative study of defect levels in GaInNAs, GaNAsSb, and GaInNAsSb for high-efficiency solar cells

    NASA Astrophysics Data System (ADS)

    Polojärvi, Ville; Aho, Arto; Tukiainen, Antti; Schramm, Andreas; Guina, Mircea

    2016-03-01

    Background doping and defect levels in GaInNAs, GaNAsSb, and GaInNAsSb solar cells with 1 eV band-gap are reported. Localized point defect induced traps were observed showing broadest defect distribution in GaInNAsSb. Incorporation of Sb reduced the unintentional p-type background doping by an order of magnitude, but increased the capture cross sections of deep levels by three orders of magnitude. The thermal activation energy of the dominating hole trap was increased from 350 meV for GaInNAs to 560 meV for GaNAsSb. Annealing of GaNAsSb solar cells improved the open circuit voltage from 280 mV to 415 mV, owing to the reduction in trap density.

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

    DOE PAGES

    Shan, Hongzhang; Blagojević, Filip; Min, Seung-Jai; Hargrove, Paul; Jin, Haoqiang; Fuerlinger, Karl; Koniges, Alice; Wright, Nicholas J.

    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. 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.

  5. 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.

  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. 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.

  9. 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.

  10. [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.

  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. PMID:26904808

  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, 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

  14. 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

  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. 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.

  17. Electronic band structure calculation of GaNAsBi alloys and effective mass study

    NASA Astrophysics Data System (ADS)

    Habchi, M. M.; Ben Nasr, A.; Rebey, A.; El Jani, B.

    2013-11-01

    Electronic band structures of GaNxAs1-x-yBiy dilute nitrides-bismides have been determined theoretically within the framework of the band anticrossing (BAC) model and k ṡ p method. We have developed computer codes based on our extended BAC model, denoted (16 × 16), in which the dimension of the used states basis was equal to 16. We have investigated the band gap and the spin orbit splitting as a function of Bi composition for alloys lattice matched to GaAs. We have found that the substitution of As element by N and Bi impurities leads to a significant reduction of band gap energy by roughly 198 meV/%Bi. Meanwhile, spin orbit splitting increases by 56 meV/%Bi regardless N content. There is an excellent agreement between the model predictions and experiment reported in the literature. In addition, alloys compositions and oscillator strengths of transition energies have been calculated for GaNAsBi alloys which represent active zone of temperature insensitive (1.55 μm and 1.3 μm) wavelength laser diodes intended for optical fiber communications. A crossover at about 0.6 eV has occurred between Eg and Δso of GaN.039As.893Bi.068. When the quaternary is lattice mismatched to GaAs, resonance energy increases with Bi content if N content decreases. On the other hand, effective mass behavior of carriers at Γ point has been discussed with respect to alloy composition, k-directions and lattice mismatch.

  18. Study of Attitudes of the Elderly Toward Aging & the Aged.

    ERIC Educational Resources Information Center

    Signori, E. I.; Kozak, J.

    This study provides a closer perspective and appreciation of what elderly people think and feel about aging and the aged. Contained herein is a summary of the recorded written responses of 200 consecutive statements received from male and female persons 65 years old and over, in response to several broad questions regarding aging and the aged. The…

  19. 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.

  20. 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

  1. Effects of hydrogenation on non-radiative defects in GaNP and GaNAs alloys: An optically detected magnetic resonance study

    SciTech Connect

    Dagnelund, D.; Chen, W. M.; Buyanova, I. A; Vorona, I. P.; Nosenko, G.; Wang, X. J.; Tu, C. W.; Yonezu, H.; Polimeni, A.; Capizzi, M.

    2012-01-15

    Photoluminescence and optically detected magnetic resonance techniques are utilized to study defect properties of GaNP and GaNAs alloys subjected to post-growth hydrogenation by low-energy sub-threshold ion beam irradiation. It is found that in GaNP H incorporation leads to activation of new defects, which has a Ga interstitial (Ga{sub i}) atom at its core and may also involve a H atom as a partner. The observed activation critically depends on the presence of N in the alloy, as it does not occur in GaP with a low level of N doping. In sharp contrast, in GaNAs hydrogen is found to efficiently passivate Ga{sub i}-related defects present in the as-grown material. A possible mechanism responsible for the observed difference in the H behavior in GaNP and GaNAs is discussed.

  2. 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

  3. 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.

  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. 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

  6. Theoretical studies of optical gain tuning by hydrostatic pressure in GaInNAs/GaAs quantum wells

    SciTech Connect

    Gladysiewicz, M.; Wartak, M. S.; Kudrawiec, R.

    2014-01-21

    In order to describe theoretically the tuning of the optical gain by hydrostatic pressure in GaInNAs/GaAs quantum wells (QWs), the optical gain calculations within kp approach were developed and applied for N-containing and N-free QWs. The electronic band structure and the optical gain for GaInNAs/GaAs QW were calculated within the 10-band kp model which takes into account the interaction of electron levels in the QW with the nitrogen resonant level in GaInNAs. It has been shown that this interaction increases with the hydrostatic pressure and as a result the optical gain for GaInNAs/GaAs QW decreases by about 40% and 80% for transverse electric and transverse magnetic modes, respectively, for the hydrostatic pressure change from 0 to 40 kilobars. Such an effect is not observed for N-free QWs where the dispersion of electron and hole energies remains unchanged with the hydrostatic pressure. This is due to the fact that the conduction and valence band potentials in GaInAs/GaAs QW scale linearly with the hydrostatic pressure.

  7. 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.

  8. Menopause Hastens Aging, Studies Suggest

    MedlinePlus

    ... senior author of both papers. "It's like the chicken or the egg: which came first? Our study ... at UCLA's Semel Institute for Neuroscience and Human Behavior, and first author of the sleep study. "In ...

  9. 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 educational and…

  10. 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.

  11. The Age Discrimination Study. Part 2.

    ERIC Educational Resources Information Center

    Flemming, Arthur S.; And Others

    By the Older Americans Amendments of 1975, the U.S. Commission on Civil Rights was directed to investigate unreasonable age discrimination in federally-assisted programs, report the findings and recommend statutory changes for administrative actions. Results of examinations of the literature, field studies and public hearings on the following…

  12. Nickel cadmium cell age sensitivity study

    SciTech Connect

    Thierfelder, H.E.; Rampel, G.; Schmerbach, J.

    1984-08-01

    The objective of this study was to investigate the effects of aging on aerospace nickel cadmium cells, and to make a recommendation on the age limitation for cells in flight batteries at time of spacecraft launch. The swelling of the positive plates, and the decrease in overcharge protection, are concluded to be the life limiting characteristics. Based on the criteria of minimum overcharge protection for maximum reliability, it was concluded that the cell age since time of activation, should be no more than three and one-half years at time of launch, to have confidence in completing a 7-1/2 year mission. This study was made using fourteen aerospace nickel cadmium cells, GE/BBD Part No. 42B015AB19. The fourteen cells were made up of two cells from each of seven lots of cells that were manufactured by GE/BBD between 1975 and 1982. The cells had been in cold storage in the shorted condition since approximately three months after activation. The fourteen cells were reconditioned, subjected to the acceptance test identically as at time of manufacture, and then opened for flooded electrode tests and chemical analyses. The electrical acceptance test data showed no correlation with the age of the cells.

  13. 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.

  14. 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

  15. 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.

  16. An Implementation Plan for NFS at NASA's NAS Facility

    NASA Technical Reports Server (NTRS)

    Lam, Terance L.; Kutler, Paul (Technical Monitor)

    1998-01-01

    This document discusses how NASA's NAS can benefit from the Sun Microsystems' Network File System (NFS). A case study is presented to demonstrate the effects of NFS on the NAS supercomputing environment. Potential problems are addressed and an implementation strategy is proposed.

  17. 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.

  18. 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.

  19. Study of jojoba oil aging by FTIR.

    PubMed

    Le Dréau, Y; Dupuy, N; Gaydou, V; Joachim, J; Kister, J

    2009-05-29

    As the jojoba oil was used in cosmetic, pharmaceutical, dietetic food, animal feeding, lubrication, polishing and bio-diesel fields, it was important to study its aging at high temperature by oxidative process. In this work a FT-MIR methodology was developed for monitoring accelerate oxidative degradation of jojoba oils. Principal component analysis (PCA) was used to differentiate various samples according to their origin and obtaining process, and to differentiate oxidative conditions applied on oils. Two spectroscopic indices were calculated to report simply the oxidation phenomenon. Results were confirmed and deepened by multivariate curve resolution-alternative least square method (MCR-ALS). It allowed identifying chemical species produced or degraded during the thermal treatment according to a SIMPLISMA pretreatment.

  20. 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.

  1. 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.

  2. 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…

  3. NAS Parallel Benchmarks Results 3-95

    NASA Technical Reports Server (NTRS)

    Saini, Subhash; Bailey, David H.; Walter, Howard (Technical Monitor)

    1995-01-01

    The NAS Parallel Benchmarks (NPB) were developed in 1991 at NASA Ames Research Center to study the performance of parallel supercomputers. The eight benchmark problems are specified in a "pencil and paper" fashion, i.e., the complete details of the problem are given in a NAS technical document. Except for a few restrictions, benchmark implementors are free to select the language constructs and implementation techniques best suited for a particular system. In this paper, we present new NPB performance results for the following systems: (a) Parallel-Vector Processors: CRAY C90, CRAY T90 and Fujitsu VPP500; (b) Highly Parallel Processors: CRAY T3D, IBM SP2-WN (Wide Nodes), and IBM SP2-TN2 (Thin Nodes 2); and (c) Symmetric Multiprocessors: Convex Exemplar SPPIOOO, CRAY J90, DEC Alpha Server 8400 5/300, and SGI Power Challenge XL (75 MHz). We also present sustained performance per dollar for Class B LU, SP and BT benchmarks. We also mention future NAS plans for the NPB.

  4. 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

  5. Age estimation using maxillary central incisors: A radiographic study

    PubMed Central

    Agarwal, Nitin; Ahuja, Parul; Sinha, Abhishek; Singh, Anil

    2012-01-01

    Background: In the field of forensic dentistry, secondary changes in teeth with advancing age have been used as reliable predictors of age in various studies. Aim: The purpose of the present study was to present a method for assessing the chronological age based on the relationship between age and morphological parameters of maxillary central incisors. Materials and Methods: Fifty subjects between 20-70 years of age were included in the study. Intraoral periapical radiographs were taken in relation to maxillary central incisors using paralleling technique. The following measurements were recorded: lengths of tooth, pulp, root and width of root and pulp at three different points. Regression formulas were used to calculate the dental age. Results: The mean estimated age showed no statistically significant difference from the actual mean age (P > 0.05). Also, maximum difference was seen for root length variable (-1.035 ± 1.86 years). PMID:23741151

  6. 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.

  7. 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.

  8. Photoreflectance spectroscopy of step-like GaInNAs/GaInNAs/GaAs quantum wells

    NASA Astrophysics Data System (ADS)

    Kudrawiec, R.; Andrzejewski, J.; Misiewicz, J.; Gollub, D.; Forchel, A.

    2005-05-01

    Photoreflectance (PR) spectroscopy has been applied to study of step-like GaInNAs/GaInNAs/GaAs double quantum well (DQW) structures grown by molecular beam epitaxy. PR features related to optical transitions in the active part of the step-like QW structure, i.e. GaInNAs/GaInNAs QW, as well as PR features related to transitions above the step-like barrier (SLB) have been clearly observed and analysed in this paper. The analysis of the QW transitions gives information about the number of confined states in the active part of the step-like QW structure. In addition, the analysis of the second portion of PR signal gives information about the band gap energy of the SLB and optical transitions between hole and electron levels confined above the SLB.

  9. Taking up physical activity in later life and healthy ageing: the English longitudinal study of ageing

    PubMed Central

    Hamer, Mark; Lavoie, Kim L; Bacon, Simon L

    2014-01-01

    Background Physical activity is associated with improved overall health in those people who survive to older ages, otherwise conceptualised as healthy ageing. Previous studies have examined the effects of mid-life physical activity on healthy ageing, but not the effects of taking up activity later in life. We examined the association between physical activity and healthy ageing over 8 years of follow-up. Methods Participants were 3454 initially disease-free men and women (aged 63.7±8.9 years at baseline) from the English Longitudinal Study of Ageing, a prospective study of community dwelling older adults. Self-reported physical activity was assessed at baseline (2002–2003) and through follow-up. Healthy ageing, assessed at 8 years of follow-up (2010-2011), was defined as those participants who survived without developing major chronic disease, depressive symptoms, physical or cognitive impairment. Results At follow-up, 19.3% of the sample was defined as healthy ageing. In comparison with inactive participants, moderate (OR, 2.67, 95% CI 1.95 to 3.64), or vigorous activity (3.53, 2.54 to 4.89) at least once a week was associated with healthy ageing, after adjustment for age, sex, smoking, alcohol, marital status and wealth. Becoming active (multivariate adjusted, 3.37, 1.67 to 6.78) or remaining active (7.68, 4.18 to 14.09) was associated with healthy ageing in comparison with remaining inactive over follow-up. Conclusions Sustained physical activity in older age is associated with improved overall health. Significant health benefits were even seen among participants who became physically active relatively late in life. PMID:24276781

  10. Biochemical markers of aging for longitudinal studies in humans.

    PubMed

    Engelfriet, Peter M; Jansen, Eugène H J M; Picavet, H Susan J; Dollé, Martijn E T

    2013-01-01

    Much progress has been made in the past decades in unraveling the mechanisms that are responsible for aging. The discovery that particular gene mutations in experimental species such as yeast, flies, and nematodes are associated with longevity has led to many important insights into pathways that regulate aging processes. However, extrapolating laboratory findings in experimental species to knowledge that is valid for the complexity of human physiology remains a major challenge. Apart from the restricted experimental possibilities, studying aging in humans is further complicated by the development of various age-related diseases. The availability of a set of biomarkers that really reflect underlying aging processes would be of much value in disentangling age-associated pathology from specific aging mechanisms. In this review, we survey the literature to identify promising biochemical markers of aging, with a particular focus on using them in longitudinal studies of aging in humans that entail repeated measurements on easily obtainable material, such as blood samples. Our search strategy was a 2-pronged approach, one focused on general mechanisms of aging and one including studies on clinical biomarkers of age-related diseases.

  11. Biochemical Markers of Aging for Longitudinal Studies in Humans

    PubMed Central

    Engelfriet, Peter M.; Jansen, Eugène H. J. M.; Picavet, H. Susan J.; Dollé, Martijn E. T.

    2013-01-01

    Much progress has been made in the past decades in unraveling the mechanisms that are responsible for aging. The discovery that particular gene mutations in experimental species such as yeast, flies, and nematodes are associated with longevity has led to many important insights into pathways that regulate aging processes. However, extrapolating laboratory findings in experimental species to knowledge that is valid for the complexity of human physiology remains a major challenge. Apart from the restricted experimental possibilities, studying aging in humans is further complicated by the development of various age-related diseases. The availability of a set of biomarkers that really reflect underlying aging processes would be of much value in disentangling age-associated pathology from specific aging mechanisms. In this review, we survey the literature to identify promising biochemical markers of aging, with a particular focus on using them in longitudinal studies of aging in humans that entail repeated measurements on easily obtainable material, such as blood samples. Our search strategy was a 2-pronged approach, one focused on general mechanisms of aging and one including studies on clinical biomarkers of age-related diseases. PMID:23382477

  12. 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)

  13. 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).

  14. 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.

  15. 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.

  16. 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…

  17. 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…

  18. 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 World" (J.…

  19. 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…

  20. 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

  1. Rodents for comparative aging studies: from mice to beavers

    PubMed Central

    Bozzella, Michael J.; Seluanov, Andrei

    2008-01-01

    After humans, mice are the best-studied mammalian species in terms of their biology and genetics. Gerontological research has used mice and rats extensively to generate short- and long-lived mutants, study caloric restriction and more. Mice and rats are valuable model organisms thanks to their small size, short lifespans and fast reproduction. However, when the goal is to further extend the already long human lifespan, studying fast aging species may not provide all the answers. Remarkably, in addition to the fast-aging species, the order Rodentia contains multiple long-lived species with lifespans exceeding 20 years (naked mole-rat, beavers, porcupines, and some squirrels). This diversity opens great opportunities for comparative aging studies. Here we discuss the evolution of lifespan in rodents, review the biology of slow-aging rodents, and show an example of how the use of a comparative approach revealed that telomerase activity coevolved with body mass in rodents. PMID:19424861

  2. Dementia in Ageing Mental Defectives: A Clinical and Neuropathological Study.

    ERIC Educational Resources Information Center

    Reid, A. H.; And Others

    1978-01-01

    The study was aimed at establishing the prevalence and clinical features of the psychoses of senescence (senile, presenile, and cerebral arteriosclerotic dementias) in 155 mentally retarded patients over the age of 45. (SBH)

  3. Rodents for comparative aging studies: from mice to beavers.

    PubMed

    Gorbunova, Vera; Bozzella, Michael J; Seluanov, Andrei

    2008-09-01

    After humans, mice are the best-studied mammalian species in terms of their biology and genetics. Gerontological research has used mice and rats extensively to generate short- and long-lived mutants, study caloric restriction and more. Mice and rats are valuable model organisms thanks to their small size, short lifespans and fast reproduction. However, when the goal is to further extend the already long human lifespan, studying fast aging species may not provide all the answers. Remarkably, in addition to the fast-aging species, the order Rodentia contains multiple long-lived species with lifespans exceeding 20 years (naked mole-rat, beavers, porcupines, and some squirrels). This diversity opens great opportunities for comparative aging studies. Here we discuss the evolution of lifespan in rodents, review the biology of slow-aging rodents, and show an example of how the use of a comparative approach revealed that telomerase activity coevolved with body mass in rodents. PMID:19424861

  4. 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.

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

    PubMed

    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

  6. Handler Reflects on NAS, Science Issues

    ERIC Educational Resources Information Center

    Lepkowski, Wil

    1978-01-01

    The current president of the National Academy of Science (NAS) is interviewed in this article. He discusses the reorganization of NAS and the National Research Council during his term of office. Concerns over environmental science, biochemistry research, and the decreasing role of science advisors to the Pentagon are presented. (MA)

  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. Age of onset of schizophrenia: perspectives from structural neuroimaging studies.

    PubMed

    Gogtay, Nitin; Vyas, Nora S; Testa, Renee; Wood, Stephen J; Pantelis, Christos

    2011-05-01

    Many of the major neuropsychiatric illnesses, including schizophrenia, have a typical age of onset in late adolescence. Late adolescence may reflect a critical period in brain development making it particularly vulnerable for the onset of psychopathology. Neuroimaging studies that focus on this age range may provide unique insights into the onset and course of psychosis. In this review, we examine the evidence from 2 unique longitudinal cohorts that span the ages from early childhood through young adulthood; a study of childhood-onset schizophrenia where patients and siblings are followed from ages 6 through to their early twenties, and an ultra-high risk study where subjects (mean age of 19 years) are studied before and after the onset of psychosis. From the available evidence, we make an argument that subtle, regionally specific, and genetically influenced alterations during developmental age windows influence the course of psychosis and the resultant brain phenotype. The importance of examining trajectories of development and the need for future combined approaches, using multimodal imaging together with molecular studies is discussed. PMID:21505117

  9. Age of Onset of Schizophrenia: Perspectives From Structural Neuroimaging Studies

    PubMed Central

    Gogtay, Nitin; Vyas, Nora S.; Testa, Renee; Wood, Stephen J.; Pantelis, Christos

    2011-01-01

    Many of the major neuropsychiatric illnesses, including schizophrenia, have a typical age of onset in late adolescence. Late adolescence may reflect a critical period in brain development making it particularly vulnerable for the onset of psychopathology. Neuroimaging studies that focus on this age range may provide unique insights into the onset and course of psychosis. In this review, we examine the evidence from 2 unique longitudinal cohorts that span the ages from early childhood through young adulthood; a study of childhood-onset schizophrenia where patients and siblings are followed from ages 6 through to their early twenties, and an ultra-high risk study where subjects (mean age of 19 years) are studied before and after the onset of psychosis. From the available evidence, we make an argument that subtle, regionally specific, and genetically influenced alterations during developmental age windows influence the course of psychosis and the resultant brain phenotype. The importance of examining trajectories of development and the need for future combined approaches, using multimodal imaging together with molecular studies is discussed. PMID:21505117

  10. [Histological study on aging changes in the human tongue].

    PubMed

    Nakayama, M

    1991-04-01

    Dryness of the mouth, taste disturbance or misswallowing may appear due to physiological changes of tongue especially in old aged person. The purpose of this study is to investigate histological changes related to aging in the human tongue, qualitatively and quantitatively. The samples were collected from 100 autopsy-cases without any pathological changes consisting of 50 males and 50 females aged between 5 and 82. Five specimens (I-V) were obtained from each tongue by frontal section. Specimen I (anterior part of tongue), III (central part), V (posterior part) were studied. Each specimen with thickness of 4 microns were stained with Hematoxylin-Eosin and Alucian-Blue. Tongue mucosa, glands such as Blandin-Nuhn gland, von Ebner gland and those glands distributed in the root of tongue, and M. longitudinalis superior were observed histologically. The study was done quantitatively by I-BAS one picture analyzer manufactured by Zeiss Co. The results of this study are as following: 1) The epithelium of lingual mucosa The thickness of epithelium decreased with aging, rather prominent on dorsal part than the lateral. 2) lingual glands Acinar atrophy increased with aging, especially quickly in females. The atrophy of the acinus started from 40 years old in Blandin-nuhn gland and 30 in von Ebner gland. However, tongue root glandular atrophy was milder in comparison with the other two glands. 3) Lingual muscles Decrease in muscle fiber diameter with aging is also observed.

  11. Age influence on periodontal tissues: a histological study.

    PubMed

    Andreescu, Claudia Florina; Mihai, Laurenţa Leila; Răescu, Mihaela; Tuculină, Mihaela Jana; Cumpătă, C N; Ghergic, Doina Lucia

    2013-01-01

    Oral mucosa becomes thinner, smooth and looses stippling aspect with aging. From histological standpoint appears: narrowing and alteration of gingival epithelium, modification of epithelial-connective interface and decreasing of keratinization. However, it cannot be detected significant histological alterations in size, shape or arrangement of epithelial cells that could be endorsed to aging process. Histological studies indicate: decreasing of keratinization, regressive changes in epithelium and fibrosis in underlying connective tissue. Parakeratosis is frequent with aging because of microtraumas, in many cases is expression of permanent inflammation. PMID:24322032

  12. 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

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

    PubMed

    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. 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.

  15. 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

  16. Toilet training age and influencing factors: a multicenter study.

    PubMed

    Tarhan, Hüseyin; Çakmak, Özgür; Akarken, İlker; Ekin, Rahmi Gökhan; Ün, Sıtkı; Uzelli, Derya; Helvacı, Mehmet; Aksu, Nejat; Yavaşcan, Önder; Mutlubaş Özsan, Fatma; Cun, Selma; Koç, Feyza; Özkarakaş, Özlem; İlbey, Yusuf Özlem; Zorlu, Ferruh

    2015-01-01

    To determine toilet training age and the factors influencing this in our country, 1500 children who had completed toilet training were evaluated in a multicenter study. The mean age of toilet training was 22.32 ± 6.57 months. The duration it took to complete toilet training was 6.60 ± 2.20 months on the average. In univariant analysis, toilet training age increased as the parental education level, specifically that of the mother, increased. The training age of children whose mothers had over 12 years of education differed significantly from that of children of mothers with less education. There was no significant difference in toilet training age with regard to the education level of the father, or the employment status of the mother. We also found significant differences with respect to family income level, toilet type and training method. In multivariant analysis, family income >5000 TL and use of a potty chair were determined to be factors affecting toilet training age. In conclusion, toilet training age in Turkey, a developing country, was found to be lower than that in developed countries.

  17. Contact allergy to topical medicaments becomes more common with advancing age: an age-stratified study.

    PubMed

    Green, Carl M; Holden, Catherine R; Gawkrodger, David J

    2007-04-01

    Eczema is common in the elderly people who often use topical medicaments. Previous studies in the elderly people have noted allergic positive patch tests in between 43% and 64% of those tested. We set out to assess whether medicament contact allergies are more common in elderly patients. We undertook a retrospective age-stratified study of all patients patch tested at the Royal Hallamshire Hospital, Sheffield, between January 1994 and July 2005. We confirmed that contact allergy to topical medicaments is more common in those aged more than 70 years compared with the younger age groups. There was no sex difference. The commonest problematic allergen types found in medicaments were fragrances and preservatives. The most frequent individual allergens were fragrance mix, Myroxylon pereirae, lanolins, local anaesthetic agents, neomycin and gentamicin, and tixocortol pivolate. The pattern of medicament contact allergens was similar to that of the younger age groups except that multiple allergic positives were more frequent and sensitivities to local anaesthetics and Myroxylon pereirae were proportionally more common. Elderly patients were more likely to have multiple contact allergies than the younger ones. Care needs to be taken when prescribing topical medicaments to elderly patients with eczema, especially for preparations that contain perfumes, lanolins, and local anaesthetics.

  18. 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

  19. 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…

  20. 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

  1. Building for the future: essential infrastructure for rodent ageing studies.

    PubMed

    Wells, Sara E; Bellantuono, Ilaria

    2016-08-01

    When planning ageing research using rodent models, the logistics of supply, long term housing and infrastructure provision are important factors to take into consideration. These issues need to be prioritised to ensure they meet the requirements of experiments which potentially will not be completed for several years. Although these issues are not unique to this discipline, the longevity of experiments and indeed the animals, requires a high level of consistency and sustainability to be maintained throughout lengthy periods of time. Moreover, the need to access aged stock or material for more immediate experiments poses many issues for the completion of pilot studies and/or short term intervention studies on older models. In this article, we highlight the increasing demand for ageing research, the resources and infrastructure involved, and the need for large-scale collaborative programmes to advance studies in both a timely and a cost-effective way.

  2. NAS-current status and future plans

    NASA Technical Reports Server (NTRS)

    Bailey, F. R.

    1987-01-01

    The Numerical Aerodynamic Simulation (NAS) has met its first major milestone, the NAS Processing System Network (NPSN) Initial Operating Configuration (IOC). The program has met its goal of providing a national supercomputer facility capable of greatly enhancing the Nation's research and development efforts. Furthermore, the program is fulfilling its pathfinder role by defining and implementing a paradigm for supercomputing system environments. The IOC is only the begining and the NAS Program will aggressively continue to develop and implement emerging supercomputer, communications, storage, and software technologies to strengthen computations as a critical element in supporting the Nation's leadership role in aeronautics.

  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. Effects of aging on P300 between late young-age and early middle-age adulthood: an electroencephalogram event-related potential study.

    PubMed

    Bourisly, Ali K

    2016-09-28

    The aim of this study was to identify age-related changes of P300 peak amplitude and P300 latency between closely separated nonsenile age groups (late young-aged adults and early middle-aged adults) and to investigate whether or not P300 has the potential to be used as a measure of cognitive aging even among nonsenile age groups. Twenty-eight adults (25-55 years old) completed an event-related potential oddball task. The elicitation of both P300 peak amplitude and P300 latency indicated age-related changes of P300. The results of the study showed that the P300 target peak amplitude was significantly larger in late young age compared with early middle age and that P300 target latency was also significantly delayed in early middle age compared with late young age. The results of this work contribute toward research efforts on a consensus on how aging affects event-related potential and/or P300. The main conclusions are that there exist significant age-related P300 changes even between closely separated, relatively younger, and nonsenile age groups, and that P300 has the potential to be used as a measure for cognitive aging even in nonsenile adults.

  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. PMID:26436456

  7. 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

  8. 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.

  9. Accelerated optical polymer aging studies for LED luminaire applications

    NASA Astrophysics Data System (ADS)

    Estupiñán, Edgar; Wendling, Peter; Kostrun, Marijan; Garner, Richard

    2013-09-01

    There is a need in the lighting industry to design and implement accelerated aging methods that accurately simulate the aging process of LED luminaire components. In response to this need, we have built a flexible and reliable system to study the aging characteristics of optical polymer materials, and we have employed it to study a commercially available LED luminaire diffuser made of PMMA. The experimental system consists of a "Blue LED Emitter" and a working surface. Both the temperatures of the samples and the optical powers of the LEDs are appropriately characterized in the system. Several accelerated aging experiments are carried out at different temperatures and optical powers over a 90 hour period and the measured transmission values are used as inputs to a degradation model derived using plausibility arguments. This model seems capable of predicting the behavior of the material as a function of time, temperature and optical power. The model satisfactorily predicts the measured transmission values of diffusers aged in luminaires at two different times and thus can be used to make application recommendations for this material. Specifically, at 35000 hours (the manufacturer's stated life of the luminaire) and at the typical operational temperature of the diffuser, the model predicts a transmission loss of only a few percent over the original transmission of the material at 450 nm, which renders this material suitable for this application.

  10. 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.

  11. 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…

  12. Accelerated heat-aging studies on fluororubber in various media

    NASA Technical Reports Server (NTRS)

    Kalfayan, S. H.; Silver, R. H.; Liu, S. S.

    1976-01-01

    Heat-aging studies were conducted on fluororubber (copolymers of vinylidene fluoride and perfluoropropylene) using N,N-dicinnamylidene-1,6-hexanediamine, a Schiff's base of 1,6-hexanediamine, and MgO as acid acceptor. The principal technique employed was chemical stress relaxation for determining network changes brought about in the heat-aged fluororubber. This technique was backed up by swelling measurements, gel permeation chromatography, and IR spectroscopy. Stress relaxation curves are plotted for a wide range of variation in parameters (time, crosslinking density, state of curing, temperature, intermittent and continuous relaxation).

  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. PMID:26758249

  14. 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.

  15. 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

  16. Ferrocyanide safety project ferrocyanide aging studies FY 1995 annual report

    SciTech Connect

    Lilga, M.A.; Alderson, E.V.; Hallen, R.T.

    1995-09-01

    This annual report gives the results of the work conducted by the Pacific Northwest Laboratory in FY 1995 on Task 3 of the Ferrocyanide Safety Project, Ferrocyanide Aging Studies. Aging refers to the dissolution and hydrolysis of simulated Hanford ferrocyanide waste in alkaline aqueous solutions by radiolytic and chemical means. The ferrocyanide simulant primarily used in these studies was dried In-Farm-1B, Rev. 7, prepared by Westinghouse Hanford Company to simulate the waste generated when the In-Farm flowsheet was used to remove radiocesium from waste supernates in single-shell tanks at the Hanford Site. In the In-Farm flowsheet, nickel ion and ferrocyanide anion were added to waste supernates to precipitate sodium nickel ferrocyanide, Na{sub 2}NiFe(CN){sub 6}, and co-precipitate radiocesium. Once the radiocesium was removed, supernates were pumped from the tanks, and new wastes from cladding removal processes or from evaporators were added. These new wastes were typically highly caustic, having hydroxide ion concentrations of over 1 M and as high as 4 M. The Aging Studies task is investigating reactions this caustic waste may have had with the precipitated ferrocyanide waste in a radiation field. In previous Aging Studies research, Na{sub 2}NiFe(CN){sub 6} in simulants was shown to dissolve in basic solutions, forming insoluble Ni(OH){sub 2} and soluble Na{sub 4}Fe(CN){sub 6}. The influence on solubility of base strength, sodium ion concentration, anions, and temperature was previously investigated. The results may indicate that even ferrocyanide sludge that did not come into direct contact with highly basic wastes may also have aged significantly.

  17. 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.

  18. 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.

  19. 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…

  20. Using somatic-cell nuclear transfer to study aging.

    PubMed

    Kishigami, Satoshi; Lee, Ah Reum; Wakayama, Teruhiko

    2013-01-01

    In mammals, a diploid genome following fertilization of haploid cells, an egg, and a spermatozoon is unique and irreproducible. This implies that the generated unique diploid genome is doomed with the individual's inevitable demise. Since it was first reported in 1997 that Dolly the sheep had been cloned, many mammalian species have been cloned successfully using somatic-cell nuclear transfer (SCNT). The success of SCNT in mammals enables us not only to reproduce offspring without germ cells, that is, to "passage" a unique diploid genome, but also to address valuable biological questions on development, nuclear reprogramming, and epigenetic memory. Successful cloning can also support epigenetic reprogramming where the aging clock is reset or reversed. Recent work using iPS cell technology has explored the practicality and led to the recapitulation of premature aging with iPSCs from progeroid laminopathies. As a result, reprogramming tools are also expected to contribute to studying biological age. However, the efficiency of animal cloning is still low in most cases and the mechanism of reprogramming in cloned embryos is still largely unclear. Here, based on recent advances, we describe an improved, more efficient mouse cloning protocol using histone deacetylase inhibitors (HDACis) and latrunculin A, which increases the success rates of producing cloned mice or establishing ES cells fivefold. This improved method of cloning will provide a strong tool to address many issues including biological aging more easily and with lower cost.

  1. Using somatic-cell nuclear transfer to study aging.

    PubMed

    Kishigami, Satoshi; Lee, Ah Reum; Wakayama, Teruhiko

    2013-01-01

    In mammals, a diploid genome following fertilization of haploid cells, an egg, and a spermatozoon is unique and irreproducible. This implies that the generated unique diploid genome is doomed with the individual's inevitable demise. Since it was first reported in 1997 that Dolly the sheep had been cloned, many mammalian species have been cloned successfully using somatic-cell nuclear transfer (SCNT). The success of SCNT in mammals enables us not only to reproduce offspring without germ cells, that is, to "passage" a unique diploid genome, but also to address valuable biological questions on development, nuclear reprogramming, and epigenetic memory. Successful cloning can also support epigenetic reprogramming where the aging clock is reset or reversed. Recent work using iPS cell technology has explored the practicality and led to the recapitulation of premature aging with iPSCs from progeroid laminopathies. As a result, reprogramming tools are also expected to contribute to studying biological age. However, the efficiency of animal cloning is still low in most cases and the mechanism of reprogramming in cloned embryos is still largely unclear. Here, based on recent advances, we describe an improved, more efficient mouse cloning protocol using histone deacetylase inhibitors (HDACis) and latrunculin A, which increases the success rates of producing cloned mice or establishing ES cells fivefold. This improved method of cloning will provide a strong tool to address many issues including biological aging more easily and with lower cost. PMID:23929101

  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. Carriers confinement study of GaNAsBi/GaAs QWs emitting at 1.3 and 1.55 μm

    SciTech Connect

    Ben Nasr, A.; Habchi, M. M.; Bilel, C.; Rebey, A. El Jani, B.

    2015-05-15

    Band structures of GaN{sub 0.58y}As{sub 1–1.58y}Bi{sub y}/GaAs quantum wells (QWs) were studied using the band anticrossing model and the envelope function approximation. The confined states energies and the oscillator strengths of interband transitions were determined for well widths L{sub W} and Bi composition y varying in the range of 4–10 nm and 0–0.07 respectively. The emissions 1.3 and 1.55 μm were reached for specific couples (L{sub W}, y). The band anticrossing effect on the in-plane carriers effective mass has been investigated at k = 0. The absorbance spectra were calculated for QWs operating at 1.3 and 1.55 μm.

  4. 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.

  5. 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.

  6. 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

  7. 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

  8. 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.…

  9. 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.

  10. Studies of aged cast stainless steel from the Shippingport reactor

    SciTech Connect

    Chopra, O.K.

    1990-10-01

    Charpy-impact and tensile tests were conducted on several cast stainless steel materials from the Shippingport reactor. Baseline mechanical properties for unaged material were determined from tests on either recovery-annealed material, i.e., annealed for 1 h at 550{degree}C and water-quenched, or material from the cooler region of the component. The materials indicate relatively modest decreases in impact energy. The results show good agreement with estimations based on accelerated laboratory-aging studies. Correlations for estimating thermal-aging degradation of cast stainless steels indicate that the degree of embrittlement of the Shippingport materials is low. The minimum room-temperature impact energies that would ever be achieved after long-term aging are >75 J/cm{sup 2} (>45 ft{center dot}lb) for all materials. The estimated activation energies for embrittlement range from 150 to 230 kJ/mole. The estimated fracture toughness J-R curves for the materials are also presented. 14 refs., 16 figs.

  11. Studies of aged cast stainless steel from the Shippingport reactor

    SciTech Connect

    Chopra, O.K.

    1991-10-01

    The mechanical properties of cast stainless steels from the Shippingport reactor have been characterized. Baseline properties for unaged materials were obtained from tests on either recovery-annealed material or material from a cooler region of the component. The materials exhibited modest decrease in impact energy and fracture toughness and a small increase in tensile strength. The fracture toughness J-R curve, J{sub IC} value, tensile flow stress, and Charpy-impact energy of the materials showed very good agreement with estimations based on accelerated laboratory aging studies. The kinetics of thermal embrittlement and degree of embrittlement at saturation, i.e., the minimum impact energy that would be achieved after long-term aging, were established from materials that were aged further in the laboratory at temperatures between 320 and 400{degree}C. The results showed very good agreement with estimates; the activation energies ranged from 125 to 250 kJ/mole and the minimum room-temperature impact energy was >75 J/cm{sup 2}. The estimated impact energy and fracture toughness J-R curve for materials from the Ringhals reactor hot and crossover-leg elbows are also presented.

  12. 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.

  13. 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.

  14. Application of experimental poverty measures to the aged.

    PubMed

    Olsen, K A

    1999-01-01

    The U.S. Census Bureau recently released new, experimental measures of poverty based on a National Academy of Sciences (NAS) panel's recommendations. This article examines the effects of the experimental measures on poverty rates among persons aged 65 or older in order to help inform policy debate. Policymakers and analysts use poverty rates to measure the successes and failures of existing programs and to create and defend new policy initiatives. The Census Bureau computes the official rates of poverty using poverty thresholds and definitions of countable income that have changed little since the official poverty measure was adopted in 1965. Amid growing concerns about the adequacy of the official poverty measure, a NAS panel undertook a study of the concepts, methodology, and data needed to measure poverty. The panel concluded in its 1995 report that the current measure no longer provides an accurate picture of relative rates of poverty for different groups in the population or of changes in poverty over time. The panel recommended changes in establishing the poverty thresholds, defining family resources, and obtaining the required data. The Census Bureau report shows how estimated levels of poverty would differ from the official level as specific recommendations of the NAS panel are implemented individually and how estimated trends would differ when many recommendations are implemented simultaneously. It computes nonstandardized and standardized poverty rates. (The latter constrains the overall poverty rate under the experimental measures to match the official rate.) This article reports poverty rates that have not been standardized and provides considerably more detail than the Census report about the effects of the experimental measures on poverty among the aged. It examines the effects of changing the poverty thresholds and the items included or excluded from the definition of available resources. It also explores the effects of the experimental measures on

  15. 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

  16. Security Controls Hurt Research, NAS Warns.

    ERIC Educational Resources Information Center

    Kolata, Gina

    1982-01-01

    A National Academy of Sciences (NAS) report found no evidence that leaks of technical information from universities or other research centers have damaged national security. However, in areas where control is warranted, decisions should be based on criteria. These criteria and issues related to security control and technological transfer are…

  17. 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…

  18. Studies on age pigments evolving into a new theory of biological aging.

    PubMed

    Yin, D

    1995-01-01

    A variety of age pigment-like fluorophores have been recognized, identified and investigated during the past three decades. They are mainly the end-products of various side-reactions of essential biological processes. Among these, the lipid peroxidation-related fluorophores formed via aldehyde-protein crosslinking are of general importance. Fluorescent advanced glycation end-products formed during glycation/Maillard reactions, are oxygen independent, carbohydrate-associated age pigment-like substances. Age pigments, particularly those identified in retinal pigment epithelium, represent another type of age pigment that originates from polyenic biomolecules, including retinoids and carotenoids. Various alpha beta-unsaturated aldehydes can also react with the amino groups of nucleotides to induce biological alteration. Although age pigments can be produced from different types of biological materials, the crosslinking of carbonyl and amino compounds is a common toxiferous process during biological life. In the context of various aging phenomena and degenerative diseases, this process may constitute an essential mechanism of aging--the carbonyl toxification process of biological aging.

  19. Aging study of silica optical fibers under acid environment

    NASA Astrophysics Data System (ADS)

    Severin, I.; El Abdi, R.; Poulain, M.

    2005-05-01

    Optical fibers are key components in telecommunication technologies. Apart from optical specifications, optical fibers are expected to keep most of their physical properties for 10 to 20 years in current operating conditions. The reliability and the expected lifetime of optical links are closely related to the action of the chemical environment on the silica network. However, the coating also contributes largely to the mechanical properties of the fibers. The aim of this work was to study the strength and the mechanical behaviour of the silica optical fibers in an acid environment. A container with ammonium bifluoride acid salt was plunged into hot water at different temperatures (55° and 75°C). This emitted acid vapors which attacked the optical fibers for a period of 1 to 18 days. An aging study was performed on silica optical fibers with standard polyacrylate coating and with hermetic carbon coating. A dynamic two-point bending bench at different faceplate velocities (100, 200, 400 and 800 μm/s) was used. For comparison, the same dynamic measurements were also carried out on non-aged fibers. After acid vapor condensation, salt crystal deposits on the fibers were displayed using an electron scanning microscope. These crystals became visible to the naked eye from the 7th day post exposure.

  20. 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

  1. Sports injuries in school-aged children. An epidemiologic study.

    PubMed

    Backx, F J; Erich, W B; Kemper, A B; Verbeek, A L

    1989-01-01

    In November 1982, epidemiologic data were collected in a unique, large scale, population-based survey on sports injuries in school-aged children living in Holland. A total of 7,468 pupils, aged 8 to 17, completed questionnaires covering a retrospective period of 6 weeks. Seven hundred ninety-one sports injuries were registered, amounting to an incidence of 10.6 sports injuries per 100 participants. In 31% of the cases, medical consultation was needed. Injuries incurred during the study period caused 36% of the children to miss one or more physical education classes and caused 6% to miss school for at least 1 day. Contusions and sprains were the most common lesions (77%). Three of four injuries involved the lower extremity, in particular the ankle. Sixty-two percent of all the injuries occurred in organized sports, 21% in physical education classes, and 17% in unsupervised sports activities. The highest injury rates were found in basketball and field hockey. In this study population, 15 and 16-year-old boys who had a high sports activity index and played team sports, particularly contact team sports, formed a high risk group.

  2. Advanced Intermediate-Temperature Na-S Battery

    SciTech Connect

    Lu, Xiaochuan; Kirby, Brent W.; Xu, Wu; Li, Guosheng; Kim, Jin Yong; Lemmon, John P.; Sprenkle, Vincent L.; Yang, Zhenguo

    2012-11-12

    In this study, we reported an intermediate-temperature (~150°C) sodium-sulfur (Na-S) battery. With a reduced operating temperature, this novel battery can potentially reduce the cost and safety issues associated with the conventional high-temperature (300~350°C) Na-S battery. A dense β"-Al2O3 solid membrane and tetraglyme were utilized as the electrolyte separator and catholyte solvent in this battery. Solubility tests indicated that cathode mixture of Na2S4 and S exhibited extremely high solubility in tetraglyme (e.g., > 4.1 M for Na2S4 + 4 S). CV scans of Na2S4 in tetraglyme revealed two pairs of redox couples with peaks at around 2.22 and 1.75 V, corresponding to the redox reactions of polysulfide species. The discharge/charge profiles of the Na-S battery showed a slope region and a plateau, indicating multiple steps and cell reactions. In-situ Raman measurements during battery operation suggested that polysulfide species were formed in the sequence of Na2S5 + S → Na2S5 + Na2S4→ Na2S4 + Na2S2 during discharge and in a reverse order during charge. This battery showed dramatic improvement in rate capacity and cycling stability over room-temperature Na-S batteries, which makes it attractive for renewable energy integration and other grid related applications.

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

    ERIC Educational Resources Information Center

    Fritzer, Penelope; Ploger, Don

    2001-01-01

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

  4. 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). PMID:25456622

  5. 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).

  6. 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. PMID:23559801

  7. Nutrition, aging and cancer: lessons from dietary intervention studies.

    PubMed

    Carruba, Giuseppe; Cocciadiferro, Letizia; Di Cristina, Antonietta; Granata, Orazia M; Dolcemascolo, Cecilia; Campisi, Ildegarda; Zarcone, Maurizio; Cinquegrani, Maria; Traina, Adele

    2016-01-01

    There is convincing epidemiological and clinical evidence that, independent of aging, lifestyle and, notably, nutrition are associated with development or progression of major human cancers, including breast, prostate, colorectal tumors, and an increasingly large collection of diet-related cancers. Mechanisms underlying this association are mostly related to the distinct epigenetic effects of different dietary patterns. In this context, Mediterranean diet has been reported to significantly reduce mortality rates for various chronic illnesses, including cardiovascular diseases, neurodegenerative diseases and cancer. Although many observational studies have supported this evidence, dietary intervention studies using a Mediterranean dietary pattern or its selected food components are still limited and affected by a rather large variability in characteristics of study subjects, type and length of intervention, selected end-points and statistical analysis. Here we review data of two of our intervention studies, the MeDiet study and the DiMeSa project, aimed at assessing the effects of traditional Mediterranean diet and/or its component(s) on a large panel of both plasma and urine biomarkers. Both published and unpublished results are presented and discussed. PMID:27057203

  8. 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

  9. NAS Panel endorses science center concept

    NASA Astrophysics Data System (ADS)

    Science and technology centers, as proposed by President Ronald Reagan in his January 1987 State of the Union message, could make “significant contributions to science and to the nation's economic competitiveness,” according to a new report by a National Academy of Sciences (NAS) panel. What will be necessary to realize these contributions, the panel cautioned, are proper management, adequate resources, and, “above all, the selection of programs for which the centers are the most effective form of organization.”NSF plans to support science and technology centers, beginning October 1, 1988, which is the start of fiscal year 1988. NSF requested guidance from the NAS panel in implementing the program. Although other government agencies will participate in the program, NSF will play the primary role.

  10. 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.

  11. 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.

  12. 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.

  13. Syntactic processing with aging: an event-related potential study.

    PubMed

    Kemmer, Laura; Coulson, Seana; De Ochoa, Esmeralda; Kutas, Marta

    2004-05-01

    To assess age-related changes in simple syntactic processing with normal aging, event-related brain potentials (ERPs) elicited by grammatical number violations as individuals read sentences for comprehension were analyzed. Violations were found to elicit a P600 of equal amplitude and latency regardless of an individual's age. Instead, advancing age was associated with a change in the scalp distribution of the P600 effect, being less asymmetric and more frontal (though still with a parietal maximum) in older than younger adults. Our results thus show that the brain's response to simple syntactic violations, unlike those reported for simple binary categorizations and simple semantic violations, is neither slowed nor diminished in amplitude by age. At the same time, the brain's processing of these grammatical number violations did engage at least somewhat different brain regions as a function of age, suggesting a qualitative change rather than any simple quantitative change in speed of processing.

  14. Ferrocyanide safety project ferrocyanide aging studies. Final report

    SciTech Connect

    Lilga, M.A.; Hallen, R.T.; Alderson, E.V.

    1996-06-01

    This final report gives the results of the work conducted by Pacific Northwest National Laboratory (PNNL) from FY 1992 to FY 1996 on the Ferrocyanide Aging Studies, part of the Ferrocyanide Safety Project. The Ferrocyanide Safety Project was initiated as a result of concern raised about the safe storage of ferrocyanide waste intermixed with oxidants, such as nitrate and nitrite salts, in Hanford Site single-shell tanks (SSTs). In the laboratory, such mixtures can be made to undergo uncontrolled or explosive reactions by heating dry reagents to over 200{degrees}C. In 1987, an Environmental Impact Statement (EIS), published by the U.S. Department of Energy (DOE), Final Environmental Impact Statement, Disposal of Hanford Defense High-Level Transuranic and Tank Waste, Hanford Site, Richland, Washington, included an environmental impact analysis of potential explosions involving ferrocyanide-nitrate mixtures. The EIS postulated that an explosion could occur during mechanical retrieval of saltcake or sludge from a ferrocyanide waste tank, and concluded that this worst-case accident could create enough energy to release radioactive material to the atmosphere through ventilation openings, exposing persons offsite to a short-term radiation dose of approximately 200 mrem. Later, in a separate study (1990), the General Accounting Office postulated a worst-case accident of one to two orders of magnitude greater than that postulated in the DOE EIS. The uncertainties regarding the safety envelope of the Hanford Site ferrocyanide waste tanks led to the declaration of the Ferrocyanide Unreviewed Safety Question (USQ) in October 1990.

  15. 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.

  16. 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.

  17. Towards New Directions in Black Studies: Black Studies, the Computer Age.

    ERIC Educational Resources Information Center

    Bryant, Henry A.

    The importance of utilizing computer-age technology in various aspects of Black Studies instruction is discussed in this paper. After stressing the continued need for Black Studies programs, the paper describes the evolution of an idea to videotape Ethnic Studies course material in order to improve instruction and make material available to…

  18. 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…

  19. 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.

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. An aging study of wire chambers with dimethyl ether

    SciTech Connect

    Jibaly, M.; Chrusch, P. Jr.; Hilgenberg, G.; Majewski, S.; Wojcik, R.; Sauli, F.; Gaudaen, J.

    1989-02-01

    The authors report results on the aging of different types of resistive and non-resistive wires in wire chambers filled with dimethyl ether (DME) of varying degrees of purity. Among the Freon impurities detected in our DME batches, only Freon-11 was found to contribute to the aging process. Of the resistive wires, Nicotin and Stablohm produced fast aging, whereas stainless steel withstood extended irradiation in purified DME (up to 1 C/cm) without any apparent damage. Gold-plated tungsten and molybdenum wires produced results comparable to those of the stainless steel.

  5. Distribution and determinants of functioning and disability in aged adults - results from the German KORA-Age study

    PubMed Central

    2013-01-01

    Background Today industrialized countries face a burgeoning aged population. Thus, there is increasing attention on the functioning and disabilities of aged adults as potential determinants of autonomy and independent living. However, there are few representative findings on the prevalence and determinants of disability in aged persons in the German population. The objective of our study is to examine the frequency, distribution and determinants of functioning and disability in aged persons and to assess the contribution of diseases to the prevalence of disability. Methods Data originate from the MONICA/KORA study, a population-based epidemiological cohort. Survivors of the original cohorts who were 65 and older were examined by telephone interview in 2009. Disability was assessed with the Health Assessment Questionnaire Disability Index (HAQ-DI). Minimal disability was defined as HAQ-DI > 0. Logistic regression was used to adjust for potential confounders and additive regression to estimate the contribution of diseases to disability prevalence. Results We analyzed a total of 4117 persons (51.2% female) with a mean age of 73.6 years (SD = 6.1). Minimal disability was present in 44.7% of all participants. Adjusted for age and diseases, disability was positively associated with female sex, BMI, low income, marital status, physical inactivity and poor nutritional status, but not with smoking and education. Problems with joint functions and eye diseases contributed most to disability prevalence in all age groups. Conclusions In conclusion, this study could show that there are vulnerable subgroups of aged adults who should receive increased attention, specifically women, those with low income, those over 80, and persons with joint or eye diseases. Physical activity, obesity and malnutrition were identified as modifiable factors for future targeted interventions. PMID:23410010

  6. [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.

  7. 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…

  8. Study of aging and embrittlement of microalloyed steel bars

    NASA Astrophysics Data System (ADS)

    Campillo, B.; Perez, R.; Martinez, L.

    1996-10-01

    The aging of hooks, anchors, and other bent reinforcing steel bars in concrete structures are considered in modern international standards. Rebend test procedures have been designed in order to predict the aging embrittlement susceptibility by submerging bent reinforcing bar specimens in boiling water. Subsequently the bars are rebent or straightened in order to determine the loss of ductility or embrittlement of the aged material. The present work considers the influence of carbon, sulfur, and niobium on the performance of reinforcing bars in rebend tests of 300 heats of microalloyed steel bars with a variety of compositions. The microstructural evidence and the statistical results clearly indicate the strong influence of carbon and sulfur on rebend failure, while niobium-rich precipitates contribute to the hardening of the ferrite grains during aging.

  9. Total body potassium in aging humans: A longitudinal study

    SciTech Connect

    Flynn, M.A.; Nolph, G.B.; Baker, A.S.; Martin, W.M.; Krause, G. )

    1989-10-01

    Total body potassium (TBK) data calculated from longitudinal measurements over 18 y of 40K by whole-body counting of 564 male and 61 female healthy humans in a 2-pi liquid scintillation counter show little change in females younger than 50 y compared with males of those ages. Males show less TBK from 41 y onward as they age, with most rapid rate of loss between 41 and 60 y. Females have a rapid loss of TBK when they are older than 60 y; the loss is at a greater rate than that of males. Percent total body fat calculated from total body weight and lean body mass (LBM) derived from TBK document greater adiposity in females at all ages except ages 51-60 y when females are similar to males in change in percent fat per year per centimeter.

  10. Behavior analysis and the study of human aging

    PubMed Central

    Derenne, Adam; Baron, Alan

    2002-01-01

    As the population of older adults continues to rise, psychologists along with other behavioral and social scientists have shown increasing interest in this age group. Although behavior analysts have contributed to research on aging, the focus has been on applications that remedy age-related deficits, rather than a concern with aging as a developmental process. In particular, there has been little interest in the central theoretical questions that have guided gerontologists. How does behavior change with advancing years, and what are the sources of those changes? We consider the possibility that this neglect reflects the long-standing commitment of behavior analysts to variables that can be experimentally manipulated, a requirement that excludes the key variable—age itself. We review the options available to researchers and present strategies that minimize deviations from the traditional features of behavior-analytic designs. Our comments are predicated on the view that aging issues within contemporary society are far too important for behavior analysts to ignore. PMID:22478383

  11. Age Effects in a Study Abroad Context: Children and Adults Studying Abroad and at Home

    ERIC Educational Resources Information Center

    Llanes, Angels; Munoz, Carmen

    2013-01-01

    This study examines the effects of learning context and age on second language development by comparing the language gains, measured in terms of oral and written fluency, lexical and syntactic complexity, and accuracy, experienced by four groups of learners of English: children in a study abroad setting, children in their at-home school, adults in…

  12. 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…

  13. 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.

  14. 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

  15. Impact of biological aging on arterial aging in American Indians: findings from the Strong Heart Family Study.

    PubMed

    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

    2016-08-01

    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.

  16. Impact of biological aging on arterial aging in American Indians: findings from the Strong Heart Family Study.

    PubMed

    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

    2016-08-01

    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

  17. 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

  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. Distinct activation profiles in microglia of different ages: a systematic study in isolated embryonic to aged microglial cultures.

    PubMed

    Lai, A Y; Dibal, C D; Armitage, G A; Winship, I R; Todd, K G

    2013-12-19

    Microglia have been implicated in disease progression for several age-related brain disorders. However, while microglia's contribution to the progression of these disorders is accepted, the effect of aging on their endogenous cellular characteristics has received limited attention. In fact, a comprehensive study of how the structure and function of microglia changes as a function of developmental age has yet to be performed. Here, we describe the functional response characteristics of primary microglial cultures prepared from embryonic, neonatal (Neo), 2-3month-old, 6-8month-old, 9-11month-old, and 13-15month-old rats. Microglial morphology, glutamate (GLU) uptake, and release of trophic and inflammatory factors were assessed under basal conditions and in microglia activated with adenosine 5'-triphosphate (ATP) or lipopolysaccharide. We found that microglia from different age groups were both morphologically and functionally distinct. Upon activation by ATP, Neo microglia were the most reactive, upregulating nitric oxide, tumor necrosis factor-α, and brain-derived neurotrophic factor release as well as GLU uptake. This upregulation translated into neurotoxicity in microglia-neuron co-cultures that were not observed with microglia of different developmental ages. Interestingly, 13-15month-old microglia exhibited similar activation profiles to Neo microglia, whereas microglia from younger adults and embryos were activated less by ATP. Our data also identify age-dependent differences in purinergic receptor subtype expression that contribute to the regulation of neuronal survival. Combined, our data demonstrate that microglial activation and purinergic receptor profiles vary non-linearly with developmental age, a potentially important finding for studies examining the role of microglia in neurodegenerative disorders.

  20. Persistence of the effect of birth size on dysglycaemia and type 2 diabetes in old age: AGES-Reykjavik Study.

    PubMed

    von Bonsdorff, Mikaela B; Muller, Majon; Aspelund, Thor; Garcia, Melissa; Eiriksdottir, Gudny; Rantanen, Taina; Gunnarsdottir, Ingibjörg; Birgisdottir, Bryndis Eva; Thorsdottir, Inga; Sigurdsson, Gunnar; Gudnason, Vilmundur; Launer, Lenore; Harris, Tamara B

    2013-08-01

    We studied the effect of birth size on glucose and insulin metabolism among old non-diabetic individuals. We also explored the combined effect of birth size and midlife body mass index (BMI) on type 2 diabetes in old age. Our study comprised 1,682 Icelanders whose birth records included anthropometrical data. The same individuals had participated in the prospective population-based Reykjavik Study, where BMI was assessed at a mean age of 47 years, and in the AGES-Reykjavik Study during 2002 to 2006, where fasting glucose, insulin and HbA1c were measured and homeostasis model assessment for the degree of insulin resistance (HOMA-IR) calculated at a mean age of 75.5 years. Type 2 diabetes was determined as having a history of diabetes, using glucose-modifying medication or fasting glucose of >7.0 mmol/l. Of the participants, 249 had prevalent type 2 diabetes in old age. Lower birth weight and body length were associated with higher fasting glucose, insulin, HOMA-IR and HbA1c among old non-diabetic individuals. Higher birth weight and ponderal index at birth decreased the risk for type 2 diabetes in old age, odds ratio (OR), 0.61 [95 % confidence interval (CI), 0.48-0.79] and 0.96 (95 % CI, 0.92-1.00), respectively. Compared with those with high birth weight and low BMI in midlife, the odds of diabetes was almost five-fold for individuals with low birth weight and high BMI (OR, 4.93; 95 % CI, 2.14-11.37). Excessive weight gain in adulthood might be particularly detrimental to the health of old individuals with low birth weight.

  1. A Guide to the Study of the Gilded Age.

    ERIC Educational Resources Information Center

    Hewett, Marie

    Designed to be used by secondary school students, this booklet makes use of Rochester (New York) related materials to teach about the popular taste of middle-class Americans living in the northeastern region of the United States in the latter part of the 19th century during the period known as the "gilded age." This was the period when the impact…

  2. Knowledge before School-Age, Is Power during School-Age: A Study of Urban Preschool and the Learning Disabled

    ERIC Educational Resources Information Center

    Johnson, Tylia

    2013-01-01

    The primary purpose of this study was to determine if urban preschool decreased the likelihood of future identification of learning disabled (LD). According to the Child Development Institute (2010) and the Learning Disabilities Association of America (2010), four to ten percent of the school-aged students in this country are learning disabled.…

  3. Girls' Stable Peer Status and Their Adulthood Adjustment: A Longitudinal Study from Age 10 to Age 43

    ERIC Educational Resources Information Center

    Zettergren, Peter; Bergman, Lars R.; Wangby, Margit

    2006-01-01

    Stable peer status clusters of rejected, popular, and average girls from ages 10 to 13 were identified and associated to young and middle adulthood adjustment. The study included a representative sample of 445 females from the longitudinal research program Individual Development and Adaptation. Results showed that, by young adulthood, rejected…

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

    PubMed Central

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

    2015-01-01

    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. PMID:25183748

  5. 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. PMID:25183748

  6. Statistical Analysis of NAS Parallel Benchmarks and LINPACK Results

    NASA Technical Reports Server (NTRS)

    Meuer, Hans-Werner; Simon, Horst D.; Strohmeier, Erich; Lasinski, T. A. (Technical Monitor)

    1994-01-01

    In the last three years extensive performance data have been reported for parallel machines both based on the NAS Parallel Benchmarks, and on LINPACK. In this study we have used the reported benchmark results and performed a number of statistical experiments using factor, cluster, and regression analyses. In addition to the performance results of LINPACK and the eight NAS parallel benchmarks, we have also included peak performance of the machine, and the LINPACK n and n(sub 1/2) values. Some of the results and observations can be summarized as follows: 1) All benchmarks are strongly correlated with peak performance. 2) LINPACK and EP have each a unique signature. 3) The remaining NPB can grouped into three groups as follows: (CG and IS), (LU and SP), and (MG, FT, and BT). Hence three (or four with EP) benchmarks are sufficient to characterize the overall NPB performance. Our poster presentation will follow a standard poster format, and will present the data of our statistical analysis in detail.

  7. 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.

  8. 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.

  9. 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.

  10. Rhetoric to action: a study of stakeholder perceptions of aging well in two local communities.

    PubMed

    Everingham, Jo-Anne; Lui, Chi-Wai; Bartlett, Helen; Warburton, Jeni; Cuthill, Michael

    2010-11-01

    This qualitative study of local perceptions of policy goals and action in relation to aging reports 31 stakeholder interviews within 2 Australian communities exploring (a) the meaning of aging well; and (b) preferred policy actions to achieve positive aging outcomes. Findings suggest that community perceptions of aging well are broadly consistent with the goals of national and international policy frameworks in focusing on 3 dimensions--health, social engagement, and security. Further, participants believe that achievement of positive aging outcomes requires a mix of self-help, community action, and government intervention--particularly government support and encouragement for aging well initiatives. PMID:20972930

  11. DNA methylation age is associated with mortality in a longitudinal Danish twin study.

    PubMed

    Christiansen, Lene; Lenart, Adam; Tan, Qihua; Vaupel, James W; Aviv, Abraham; McGue, Matt; Christensen, Kaare

    2016-02-01

    An epigenetic profile defining the DNA methylation age (DNAm age) of an individual has been suggested to be a biomarker of aging, and thus possibly providing a tool for assessment of health and mortality. In this study, we estimated the DNAm age of 378 Danish twins, age 30-82 years, and furthermore included a 10-year longitudinal study of the 86 oldest-old twins (mean age of 86.1 at follow-up), which subsequently were followed for mortality for 8 years. We found that the DNAm age is highly correlated with chronological age across all age groups (r = 0.97), but that the rate of change of DNAm age decreases with age. The results may in part be explained by selective mortality of those with a high DNAm age. This hypothesis was supported by a classical survival analysis showing a 35% (4-77%) increased mortality risk for each 5-year increase in the DNAm age vs. chronological age. Furthermore, the intrapair twin analysis revealed a more-than-double mortality risk for the DNAm oldest twin compared to the co-twin and a 'dose-response pattern' with the odds of dying first increasing 3.2 (1.05-10.1) times per 5-year DNAm age difference within twin pairs, thus showing a stronger association of DNAm age with mortality in the oldest-old when controlling for familial factors. In conclusion, our results support that DNAm age qualifies as a biomarker of aging. PMID:26594032

  12. 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.

  13. Aging reduces experience-induced sensorimotor plasticity. A magnetoencephalographic study.

    PubMed

    Mary, Alison; Bourguignon, Mathieu; Wens, Vincent; Op de Beeck, Marc; Leproult, Rachel; De Tiège, Xavier; Peigneux, Philippe

    2015-01-01

    Modulation of the mu-alpha and mu-beta spontaneous rhythms reflects plastic neural changes within the primary sensorimotor cortex (SM1). Using magnetoencephalography (MEG), we investigated how aging modifies experience-induced plasticity after learning a motor sequence, looking at post- vs. pre-learning changes in the modulation of mu rhythms during the execution of simple hand movements. Fifteen young (18-30 years) and fourteen older (65-75 years) right-handed healthy participants performed auditory-cued key presses using all four left fingers simultaneously (Simple Movement task - SMT) during two separate sessions. Following both SMT sessions, they repeatedly practiced a 5-elements sequential finger-tapping task (FTT). Mu power calculated during SMT was averaged across 18 gradiometers covering the right sensorimotor region and compared before vs. after sequence learning in the alpha (9/10/11Hz) and the beta (18/20/22Hz) bands separately. Source power maps in the mu-alpha and mu-beta bands were localized using Dynamic Statistical Parametric Mapping (dSPM). The FTT sequence was performed faster at retest than at the end of the learning session, indicating an offline boost in performance. Analyses conducted on SMT sessions revealed enhanced rebound after learning in the right SM1, 3000-3500ms after the initiation of movement, in young as compared to older participants. Source reconstruction indicated that mu-beta is located in the precentral gyrus (motor processes) and mu-alpha is located in the postcentral gyrus (somatosensory processes) in both groups. The enhanced post-movement rebound in young subjects potentially reflects post-training plastic changes in SM1. Age-related decreases in post-training modulatory effects suggest reduced experience-dependent plasticity in the aging brain.

  14. 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.

  15. 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…

  16. 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…

  17. 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"…

  18. 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…

  19. Age, Intelligence, and Event-Related Brain Potentials during Late Childhood: A Longitudinal Study.

    ERIC Educational Resources Information Center

    Stauder, Johannes E. A.; van der Molen, Maurits W.; Molenaar, Peter C. M.

    2003-01-01

    Studied the relationship between event-related brain activity, age, and intelligence using a visual oddball task presented to girls at 9, 10, and 11 years of age. Findings for 26 girls suggest a qualitative shift in the relation between event-related brain activity and intelligence between 9 and 10 years of age. (SLD)

  20. Modeling Active Aging and Explicit Memory: An Empirical Study.

    PubMed

    Ponce de León, Laura Ponce; Lévy, Jean Pierre; Fernández, Tomás; Ballesteros, Soledad

    2015-08-01

    The rapid growth of the population of older adults and their concomitant psychological status and health needs have captured the attention of researchers and health professionals. To help fill the void of literature available to social workers interested in mental health promotion and aging, the authors provide a model for active aging that uses psychosocial variables. Structural equation modeling was used to examine the relationships among the latent variables of the state of explicit memory, the perception of social resources, depression, and the perception of quality of life in a sample of 184 older adults. The results suggest that explicit memory is not a direct indicator of the perception of quality of life, but it could be considered an indirect indicator as it is positively correlated with perception of social resources and negatively correlated with depression. These last two variables influenced the perception of quality of life directly, the former positively and the latter negatively. The main outcome suggests that the perception of social support improves explicit memory and quality of life and reduces depression in active older adults. The findings also suggest that gerontological professionals should design memory training programs, improve available social resources, and offer environments with opportunities to exercise memory.

  1. Chaperonomics, a new tool to study ageing and associated diseases.

    PubMed

    Brocchieri, Luciano; Conway de Macario, Everly; Macario, Alberto J L

    2007-01-01

    The participation of molecular chaperones in the process of senescence and in the mechanisms of age-related diseases is currently under investigation in many laboratories. However, accurate, complete information about the number and diversity of chaperone genes in any given genome is scarce. Consequently, the results of efforts aimed at elucidating the role of chaperones in ageing and disease are often confusing and contradictory. To remedy this situation, we have developed chaperonomics, including means to identify and characterize chaperone genes and their families applicable to humans and model organisms. The problem is difficult because in eukaryotic organisms chaperones have evolved into complex multi-gene families. For instance, the occurrence of multiple paralogs in a single genome makes it difficult to interpret results if consideration is not given to the fact that similar but distinct chaperone genes can be differentially expressed in separate cellular compartments, tissues, and developmental stages. The availability of complete genome sequences allows implementation of chaperonomics with the purpose of understanding the composition of chaperone families in all cell compartments, their evolutionary and functional relations and, ultimately, their role in pathogenesis. Here, we present a series of concatenated, complementary procedures for identifying, characterizing, and classifying chaperone genes in genomes and for elucidating evolutionary relations and structural features useful in predicting functional properties. We illustrate the procedures with applications to the complex family of hsp70 genes and show that the kind of data obtained can provide a solid basis for future research.

  2. 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.

  3. Undercontrolled Temperament at Age 3 Predicts Disordered Gambling at Age 32: A Longitudinal Study of a Complete Birth Cohort

    PubMed Central

    Slutske, Wendy S.; Moffitt, Terrie E.; Poulton, Richie; Caspi, Avshalom

    2013-01-01

    Using data from the large, 30-year prospective Dunedin cohort study, we examined whether preexisting individual differences in childhood temperament predicted adulthood disordered gambling (a diagnosis covering the full continuum of gambling-related problems). A 90-min observational assessment at age 3 was used to categorize children into five temperament groups, including one primarily characterized by behavioral and emotional undercontrol. The children with undercontrolled temperament at 3 years of age were more than twice as likely to evidence disordered gambling at ages 21 and 32 than were children who were well-adjusted at age 3. These associations could not be explained by differences in childhood IQ or family socioeconomic status. Cleanly demonstrating the temporal relation between behavioral undercontrol and adult disordered gambling is an important step toward building more developmentally sensitive theories of disordered gambling and may put researchers in a better position to begin considering potential routes to disordered-gambling prevention through enhancing self-control and emotional regulation. PMID:22457426

  4. Study of aging of silicone rubber biomaterials with NMR.

    PubMed

    Pfleiderer, B; Xu, P; Ackerman, J L; Garrido, L

    1995-09-01

    Multinuclear nuclear magnetic resonance (NMR) spectroscopy (29Si, 13C, 1H) is used to characterize the aging process of silicone rubber-based biomaterials in a rat model. 1H NMR relaxation measurements (spin-lattice, T1, and spin-spin, T2, relaxation times) were performed to better understand the molecular dynamics of polysiloxane chains in implants. After 1 year of implantation in animals, changes in the 1H T2 relaxation times and the NMR spectra were observed in polydimethylsiloxane, Silastic sheets and chin implants, while these measurements remain unchanged in finger joints. Very small amounts of fat were detected in all types of silicone rubber implants at the end of the implantation period. This work shows that free silicone migrates from the implants to adjacent tissues and distant sites, such as spleen or liver, and is chemically modified.

  5. Accelerated aging studies and environmental stability of prototype tamper tapes

    SciTech Connect

    Wright, B.W.; Wright, C.W.; Bunk, A.R.

    1995-05-01

    This report describes the results of accelerated aging experiments (weathering) conducted on prototype tamper tapes bonded to a variety of surface materials. The prototype tamper tapes were based on the patented Confirm{reg_sign} tamper-indicating technology developed and produced by 3M Company. Tamper tapes bonded to surfaces using pressure sensitive adhesive (PSA) and four rapid-set adhesives were evaluated. The configurations of the PSA-bonded tamper tapes were 1.27-cm-wide Confirm{reg_sign} 1700 windows with vinyl underlay and 2.54-cm-wide Confirm{reg_sign} 1700 windows with vinyl and polyester underlays. The configurations of the rapid-set adhesive-bonded tamper tapes were 2.54-cm-wide Confirm{reg_sign} (1700, 1500 with and without primer, and 1300) windows with vinyl underlay. Surfaces used for bonding included aluminum, steel, stainless steel, Kevlar{reg_sign}, brass, copper, fiberglass/resin with and without gel coat, polyurethane-painted steel, acrylonitrile:butadiene:styrene plastic, polyester fiberglass board, Lexan polycarbonate, and cedar wood. Weathering conditions included a QUV cabinet (ultraviolet light at 60{degrees}C, condensing humidity at 40{degrees}C), a thermal cycling cabinet (-18{degrees}C to 46{degrees}C), a Weather-O-Meter (Xenon lamp), and exposure outdoors in Daytona Beach, Florida. Environmental aging exposures lasted from 7 weeks to 5 months. After exposure, the tamper tapes were visually examined and tested for transfer resistance. Tamper tapes were also exposed to a variety of chemical liquids (including organic solvents, acids, bases, and oxidizing liquids) to determine chemical resistance and to sand to determine abrasion resistance.

  6. Muscle Quality and Myosteatosis: Novel Associations With Mortality Risk: The Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study.

    PubMed

    Reinders, Ilse; Murphy, Rachel A; Brouwer, Ingeborg A; Visser, Marjolein; Launer, Lenore; Siggeirsdottir, Kristin; Eiriksdottir, Gudny; Gudnason, Vilmundur; Jonsson, Palmi V; Lang, Thomas F; Harris, Tamara B

    2016-01-01

    Muscle composition may affect mortality risk, but prior studies have been limited to specific samples or less precise determination of muscle composition. We evaluated associations of thigh muscle composition, determined using computed tomography imaging, and knee extension strength with mortality risk among 4,824 participants aged 76.4 (standard deviation (SD), 5.5) years from the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study (2002-2006). Cox proportional hazards models were used to estimate hazard ratios. After 8.8 years of follow-up, there were 1,942 deaths. For men, each SD-increment increase in muscle lean area, muscle quality, and strength was associated with lower mortality risk, with decreases ranging between 11% and 22%. Each SD-increment increase in intermuscular adipose tissue and intramuscular adipose tissue was associated with higher mortality risk (hazard ratio (HR) = 1.13 (95% confidence interval (CI): 1.06, 1.22) and HR = 1.23 (95% CI: 1.15, 1.30), respectively). For women, each SD-increment increase in muscle lean area, muscle quality, and strength was associated with lower mortality risk, with decreases ranging between 12% and 19%. Greater intramuscular adipose tissue was associated with an 8% higher mortality risk (HR = 1.08, 95% CI: 1.01, 1.16). This study shows that muscle composition is associated with mortality risk. These results also show the importance of improving muscle strength and area and lowering muscle adipose tissue infiltration.

  7. Age-related weakness of proximal muscle studied with motor cortical mapping: a TMS study.

    PubMed

    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 that preserve

  8. NasT-Mediated Antitermination Plays an Essential Role in the Regulation of the Assimilatory Nitrate Reductase Operon in Azotobacter vinelandii

    PubMed Central

    Pierson, Leland S.; Rensing, Christopher; Gunatilaka, Malkanthi K.; Kennedy, Christina

    2012-01-01

    Azotobacter vinelandii is a well-studied model system for nitrogen fixation in bacteria. Regulation of nitrogen fixation in A. vinelandii is independent of NtrB/NtrC, a conserved nitrogen regulatory system in proteobacteria. Previous work showed that an ntrC mutation in A. vinelandii resulted in a loss of induction of assimilatory nitrate and nitrite reductases encoded by the nasAB operon. In addition to NtrC, several other proteins, including NasT, a protein containing a potential RNA-binding domain ANTAR (AmiR and NasR transcription antitermination regulators), have been implicated in nasAB regulation. In this work, we characterize the sequence upstream of nasA and identify several DNA sequence elements, including two potential NtrC binding sites and a putative intrinsic transcriptional terminator upstream of nasA that are potentially involved in nasAB regulation. Our analyses confirm that the nasAB promoter, PnasA, is under NtrC control. However, unlike NtrC-regulated promoters in enteric bacteria, PnasA shows high activity in the presence of ammonium; in addition, the PnasA activity is altered in the nifA gene mutation background. We discuss the implication of these results on NtrC-mediated regulation in A. vinelandii. Our study provides direct evidence that induction of nasAB is regulated by NasT-mediated antitermination, which occurs within the leader region of the operon. The results also support the hypothesis that NasT binds the promoter proximal hairpin of nasAB for its regulatory function, which contributes to the understanding of the regulatory mechanism of ANTAR-containing antiterminators. PMID:22773651

  9. 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.

  10. Perceptions of Successful Ageing Among Iranian Elders: Insights From a Qualitative Study.

    PubMed

    Zanjari, Nasibeh; Sharifian Sani, Maryam; Hosseini Chavoshi, Meimanat; Rafiey, Hassan; Mohammadi Shahboulaghi, Farahnaz

    2016-10-01

    The aim of this article is to explore the perceptions of successful ageing among Iranian elderly. The data were collected in Tehran city on 60 older adults using a semistructured interview. The collected data were analyzed using directed content analysis. The findings revealed various dimensions of successful ageing among Iranian older adults. Social well-being is the most prevalent dimension of successful ageing, followed by psychological well-being, physical health, spirituality and transcendence, financial security, and an elder-friendly environmental and social context. Also, the findings from this study provide a new understanding of successful ageing in the context of Iran and contribute additional elements. This qualitative study highlights the importance of multidimensional and contextual viewpoints to successful ageing. In conclusion, to achieve multidimensional successful ageing, the interaction between all levels of successful ageing such as individual, family, and environment must be considered.

  11. Perceptions of Successful Ageing Among Iranian Elders: Insights From a Qualitative Study.

    PubMed

    Zanjari, Nasibeh; Sharifian Sani, Maryam; Hosseini Chavoshi, Meimanat; Rafiey, Hassan; Mohammadi Shahboulaghi, Farahnaz

    2016-10-01

    The aim of this article is to explore the perceptions of successful ageing among Iranian elderly. The data were collected in Tehran city on 60 older adults using a semistructured interview. The collected data were analyzed using directed content analysis. The findings revealed various dimensions of successful ageing among Iranian older adults. Social well-being is the most prevalent dimension of successful ageing, followed by psychological well-being, physical health, spirituality and transcendence, financial security, and an elder-friendly environmental and social context. Also, the findings from this study provide a new understanding of successful ageing in the context of Iran and contribute additional elements. This qualitative study highlights the importance of multidimensional and contextual viewpoints to successful ageing. In conclusion, to achieve multidimensional successful ageing, the interaction between all levels of successful ageing such as individual, family, and environment must be considered. PMID:27380778

  12. 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.

  13. 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.

  14. 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. PMID:24799415

  15. Lesson Study Comes of Age in North America

    ERIC Educational Resources Information Center

    Lewis, Catherine; Perry, Rebecca; Hurd, Jacqueline; O'Connell, Mary Pat

    2006-01-01

    Lesson study, the dominant form of professional development for teachers in Japan, has spread rapidly in the U.S. since 1999. In this article, the authors discuss the growth and success of lesson study at Highlands Elementary School in California's San Mateo-Foster City School District and identify conditions needed for scale-up. They also discuss…

  16. 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…

  17. 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

  18. Morphometric skin characteristics dependent on chronological and biological age: the Leiden Longevity Study.

    PubMed

    Waaijer, Mariette E C; Gunn, David A; Catt, Sharon D; van Ginkel, Michael; de Craen, Anton J M; Hudson, Nicole M; van Heemst, Diana; Slagboom, P Eline; Westendorp, Rudi G J; Maier, Andrea B

    2012-12-01

    The effect of chronological age on skin characteristics is readily visible, and its underlying histological changes have been a field of study for several years. However, the effect of biological age (i.e. a person's rate of ageing compared to their chronological age) on the skin has so far only been studied in facial photographs. Skin biopsies obtained from middle-aged offspring of nonagenarian siblings that are genetically enriched for longevity were compared to their partners who represent the general Dutch population. Though of the same chronological age, the offspring were previously observed to be of a younger biological age than their partners. The biopsies were analysed on several aspects epidermal and elastic fibre morphology. We investigated whether these skin characteristics were dependent on chronological age, familial longevity (the difference between the offspring and partners) and Framingham heart risk scores, adjusted for external stressors. A decreased thickness and flattening of the epidermis as well as an increased amount of elastic fibres in the reticular dermis were observed with chronological age (P < 0.001, P < 0.001 and P = 0.03, respectively), but no effect of familial longevity was found. The Framingham heart risk score was associated with some skin characteristics. A slower rate of skin ageing does not mark offspring from nonagenarian siblings. Epidermal and elastic fibre morphometric characteristics are not a potential marker for familial longevity in middle-aged subjects enriched for familial longevity.

  19. Factors Influencing Menarcheal Age: Results From the Cohort of Tehran Lipid and Glucose Study

    PubMed Central

    Ramezani Tehrani, Fahimeh; Mirmiran, Parvin; Gholami, Roya; Moslehi, Nazanin; Azizi, Feriedon

    2014-01-01

    Background: Menarche is considered as a milestone in the women’s reproductive life. Most existing studies on factors influencing menarcheal age had cross-sectional designs and their finding were controversial. Objectives: We aimed to determine some factors affecting the age at menarche in a cohort study with an average of ten-year follow-up; the study was conducted within the framework of Tehran Lipid and Glucose Study (TLGS). Materials and Methods: For the purpose of the present study, we recruited all the females aged 12 to 18 years participated in TLGS whose menarche had not begun at the initiation of the study, but occurred during their follow-up. The effect of premenarcheal status of various factors including socioeconomic and anthropometric parameters, physical activity, energy expenditure, and exposure to tobacco smoke on menarcheal age was explored. Results: The mean of age at menarche was 13.06 ± 1.24 years. There were significant statistical associations between age of the participants’ mothers at menarche (r = 0.66, P < 0.001), maternal education (r = -0.04, P = 0.002), and body mass index (BMI) before menarcheal (r = 0.25, P = 0.027) with age at menarche. There was no significant correlation between age at menarche, with either of maternal employment, premenarcheal physical activity, energy expenditure, and passive smoking. Conclusions: Among various factor influencing menarcheal age, premenarcheal BMI is modifiable, and considering its significance, could prevent early or late menarches. PMID:25237321

  20. Cumulative lead exposure in community-dwelling adults and fine motor function: comparing standard and novel tasks in the VA Normative Aging Study

    PubMed Central

    Grashow, Rachel; Spiro, Avron; Taylor, Kathryn M.; Newton, Kimberly; Shrairman, Ruth; Landau, Alexander; Sparrow, David; Hu, Howard; Weisskopf, Marc

    2013-01-01

    Background and Aims Lead exposure in children and occupationally-exposed adults has been associated with reduced visuomotor and fine motor function. However, associations in environmentally-exposed adults remain relatively unexplored. To address this, we examined the association between cumulative lead exposure—as measured by lead in bone—and performance on the Grooved Pegboard (GP) manual dexterity task, as well as on handwriting tasks using a novel assessment approach, among men in the VA Normative Aging Study (NAS). Methods GP testing was done with 362 NAS participants, and handwriting assessment with 328, who also had tibia and patella lead measurements made with K-X-Ray Fluorescence (KXRF). GP scores were time (sec) to complete the task with the dominant hand. The handwriting assessment approach assessed the production of signature and cursive lowercase l and m letter samples. Signature and lm task scores reflect consistency in repeated trials. We used linear regression to estimate associations and 95% confidence intervals (CI) with adjustment for age, smoking, education, income and computer experience. A backward elimination algorithm was used in the subset with both GP and handwriting assessment to identify variables predictive of each outcome. Results The mean (SD) participant age was 69.1 (7.2) years; mean patella and tibia concentrations were 25.0 (20.7) μg/g and 19.2 (14.6) μg/g, respectively. In multivariable-adjusted analyses, GP performance was associated with tibia (β per 15 μg/g bone = 4.66, 95% CI: 1.73, 7.58, p=0.002) and patella (β per 20 μg/g = 3.93, 95% CI: 1.11, 6.76, p = 0.006). In multivariable adjusted models of handwriting production, only the lm-pattern task showed a significant association with tibia (β per 15 μg/g bone = 1.27, 95% CI: 0.24, 2.29, p = 0.015), such that lm pattern production was more stable with increasing lead exposure. GP and handwriting scores were differentially sensitive to education, smoking, computer

  1. 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)

  2. Cross-Sectional Study of Gender Role Conflict Examining College-Aged and Middle-Aged Men.

    ERIC Educational Resources Information Center

    Cournoyer, Robert J.; And Others

    1995-01-01

    College-aged (n=88) and middle-aged (n=89) men completed 5 measures that assess gender role conflict and psychological well-being. Results indicate that, compared with college-aged men, middle-aged men were less conflicted about success, power, and competition, but were more conflicted about work and family responsibilities. The discussion focuses…

  3. The longitudinal urban cohort ageing study (LUCAS): study protocol and participation in the first decade

    PubMed Central

    2012-01-01

    Background We present concept, study protocol and selected baseline data of the Longitudinal Urban Cohort Ageing Study (LUCAS) in Germany. LUCAS is a long-running cohort study of community-dwelling seniors complemented by specific studies of geriatric patients or diseases. Aims were to (1) Describe individual ageing trajectories in a metropolitan setting, documenting changes in functional status, the onset of frailty, disability and need of care; (2) Find determinants of healthy ageing; (3) Assess long-term effects of specific health promotion interventions; (4) Produce results for health care planning for fit, pre-frail, frail and disabled elderly persons; (5) Set up a framework for embedded studies to investigate various hypotheses in specific subgroups of elderly. Methods/Design In 2000, twenty-one general practitioners (GPs) were recruited in the Hamburg metropolitan area; they generated lists of all their patients 60 years and older. Persons not terminally ill, without daily need of assistance or professional care were eligible. Of these, n = 3,326 (48 %) agreed to participate and completed a small (baseline) and an extensive health questionnaire (wave 1). In 2007/2008, a re-recruitment took place including 2,012 participants: 743 men, 1,269 women (647 deaths, 197 losses, 470 declined further participation). In 2009/2010 n = 1,627 returned the questionnaire (90 deaths, 47 losses, 248 declined further participation) resulting in a good participation rate over ten years with limited and quantified dropouts. Presently, follow-up data from 2007/2008 (wave 2) and 2009/2010 (wave 3) are available. Data wave 4 is due in 2011/2012, and the project will be continued until 2013. Information on survival and need of nursing care was collected continuously and cross-checked against official records. We used Fisher’s exact test and t-tests. The study served repeatedly to evaluate health promotion interventions and concepts. Discussion LUCAS shows that a cohort

  4. 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…

  5. 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…

  6. 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.

  7. 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…

  8. 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.

  9. Age relations of cardiovascular risk factors in a traditional Melanesian society: the Kitava Study.

    PubMed

    Lindeberg, S; Berntorp, E; Nilsson-Ehle, P; Terént, A; Vessby, B

    1997-10-01

    This study examined cross-sectional age relations of blood pressure, anthropometric indexes, serum lipids, and hemostatic variables in 203 subsistence horticulturists aged 20-86 y in Kitava, Trobriand Islands, Papua New Guinea. The population is characterized by extreme leanness (despite food abundance), low blood pressure, low plasma plasminogen activator inhibitor 1 activity, and rarity of cardiovascular disease. Tubers, fruit, fish, and coconut are dietary staples whereas dairy products, refined fat and sugar, cereals, and alcohol are absent and salt intake is low. Although diastolic blood pressure was not associated with age in Kitavans, systolic blood pressure increased linearly after 50 y of age in both sexes. Body mass index decreased with age in both sexes. Serum total cholesterol, triacylglycerol, low-density-lipoprotein cholesterol, and apolipoprotein B increased in males between 20 and 50 y of age, whereas high-density-lipoprotein cholesterol and apolipoprotein A-I decreased. There were no significant differences in these indexes with age in the few females studied. A slight linear age-related increase of lipoprotein(a) was present in males. Plasma fibrinogen, factor VII clotting activity, factor VIII clotting activity, and von Willebrand factor antigen increased with age in both sexes but plasminogen activator inhibitor 1 activity did not. The modest or absent relations between the indexes measured and age are apparently important explanations of the virtual nonexistence of stroke and ischemic heart disease in Kitava.

  10. 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.

  11. 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. PMID:26548377

  12. 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

  13. 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. PMID:22983032

  14. Impact of traditional Chinese medicine on age trajectories of health: evidence from the Taiwan Longitudinal Study on Aging.

    PubMed

    Hsu, Yu-Ching; Chiu, Ching-Ju; Wray, Linda A; Beverly, Elizabeth A; Tseng, Shuo-Ping

    2015-02-01

    Although traditional Chinese medicine (TCM) is widely used, its effect on health outcomes is not well understood. This study employed a cohort sequential design to investigate levels and rates of change in health from midlife to older adulthood in TCM users and nonusers. A sample of 1,302 community-dwelling adults aged 53 to 80 was selected from individuals interviewed in the 1999 Taiwan Longitudinal Study on Aging (TLSA) and reinterviewed in 2003 and 2007. TCM users were identified as participants who reported visiting a Chinese medicine clinic in the year before each of the three interviews. Health outcomes included physical function, self-rated health, cognitive function, and depressive symptoms. Approximately one in five adults reported that they used TCM in at least one wave of the 3 interview years, but less than one in twenty across all waves. Controlling for time-varying sociodemographic and health conditions, levels and rates of change in physical and cognitive function did not differ according to TCM use. Although adults who reported using TCM had higher depressive symptoms (βTCM = 0.979, 95% confidence interval (CI) = 0.200-1.758) and poorer self-rated health (βTCM = -0.267, 95% CI = -0.267 to -0.081) at baseline, their rates of change in these outcomes did not differ from those who did not use TCM. Subgroup analyses revealed that TCM use benefited adults with higher depressive symptoms by attenuating worsening depressive symptoms (βTCM ×Age = -0.221, 95% CI = -0.434 to -0.007). Further research aimed at understanding the specific mechanisms by which TCM affects health outcomes is warranted.

  15. 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

  16. The effects of aging on dopaminergic neurotransmission: a microPET study of [11C]-raclopride binding in the aged rodent brain.

    PubMed

    Hoekzema, E; Herance, R; Rojas, S; Pareto, D; Abad, S; Jiménez, X; Figueiras, F P; Popota, F; Ruiz, A; Torrent, È; Fernández-Soriano, F J; Rocha, M; Rovira, M; Víctor, V M; Gispert, J D

    2010-12-29

    Rodent models are frequently used in aging research to investigate biochemical age effects and aid in the development of therapies for pathological and non-pathological age-related degenerative processes. In order to validate the use of animal models in aging research and pave the way for longitudinal intervention-based animal studies, the consistency of cerebral aging processes across species needs to be evaluated. The dopaminergic system seems particularly susceptible to the aging process, and one of the most consistent findings in human brain aging research is a decline in striatal D2-like receptor (D2R) availability, quantifiable by positron emission tomography (PET) imaging. In this study, we aimed to assess whether similar age effects can be discerned in rat brains, using in vivo molecular imaging with the radioactive compound [(11)C]-raclopride. We observed a robust decline in striatal [(11)C]-raclopride uptake in the aged rats in comparison to the young control group, comprising a 41% decrement in striatal binding potential. In accordance with human studies, these results indicate that substantial reductions in D2R availability can be measured in the aged striatal complex. Our findings suggest that rat and human brains exhibit similar biochemical alterations with age in the striatal dopaminergic system, providing support for the pertinence of rodent models in aging research.

  17. 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

  18. 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.

  19. 5'-coding sequence of the nasA gene of Azotobacter vinelandii is required for efficient expression.

    PubMed

    Wang, Baomin; Wang, Yumei; Kennedy, Christina

    2014-10-01

    The operon nasACBH in Azotobacter vinelandii encodes nitrate and nitrite reductases that sequentially reduce nitrate to nitrite and to ammonium for nitrogen assimilation into organic molecules. Our previous analyses showed that nasACBH expression is subject to antitermination regulation that occurs upstream of the nasA gene in response to the availability of nitrate and nitrite. In this study, we continued expression analyses of the nasA gene and observed that the nasA 5'-coding sequence plays an important role in gene expression, as demonstrated by the fact that deletions caused over sixfold reduction in the expression of the lacZ reporter gene. Further analysis suggests that the nasA 5'-coding sequence promotes gene expression in a way that is not associated with weakened transcript folding around the translational initiation region or codon usage bias. The findings from this study imply that there exists potential to improve gene expression in A. vinelandii by optimizing 5'-coding sequences.

  20. 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.

  1. 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.

  2. Building and commissioning of a setup to study ageing phenomena in gaseous detectors

    NASA Astrophysics Data System (ADS)

    Abuhoza, A.; Schmidt, H. R.; Biswas, S.; Frankenfeld, U.; Hehner, J.; Schmidt, C. J.

    2016-07-01

    In high-rate heavy-ion experiments, gaseous detectors encounter big challenges in terms of degradation of their performance due to a phenomenon called ageing. A setup for high precision ageing studies has been constructed and commissioned at the GSI detector laboratory. The setup as well as the gas system have been carefully optimized to reach a high sensitivity for ageing effects. Two different materials have been examined for their influence on gaseous detectors: RTV-3145 and Gerband 705. The details of the construction of the ageing test setup and the test results will be presented.

  3. 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).

  4. Hypothesis: is yeast a clock model to study the onset of humans aging phenotypes?

    PubMed

    Mazzoni, Cristina; Mangiapelo, Eleonora; Palermo, Vanessa; Falcone, Claudio

    2012-01-01

    In this paper we report the growth and aging of yeast colonies derived from single cells isolated by micromanipulation and seeded one by one on separated plates to avoid growth interference by surrounding colonies. We named this procedure clonal life span, and it could represent a third way of studying aging together with the replicative life span and chronological life span. In this study we observed over time the formation of cell mass similar to the human "senile warts" (seborrheic keratoses), the skin lesions that often appear after 30 years of life and increase in number and size over the years. We observed that similar signs of aging appear in yeast colonies after about 27 days of growth and increase during aging. In this respect we hypothesize to use yeast as a clock to study the onset of human aging phenotypes.

  5. 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. PMID:26975048

  6. 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

  7. 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.

  8. Predictors and characteristics of successful aging among men: a 48-year longitudinal study.

    PubMed

    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 predictors of favorable overall outcome included good peer social adjustment, an absence of troubled parental discipline, and an absence of immature defensive behaviors when angry. However, young adult factors were more predictive of outcomes in middle age than in early old age, as predictor effect sizes decreased between the first follow-up and the second follow-up 16 years later. Findings support the possibility of both favorable and unfavorable changes in the second half of life that may diminish the impact of some young adult characteristics and family environments on adjustment in early old age. PMID:23855185

  9. 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…

  10. Perceiving Age and Gender in Unfamiliar Faces: An fMRI Study on Face Categorization

    ERIC Educational Resources Information Center

    Wiese, Holger; Kloth, Nadine; Gullmar, Daniel; Reichenbach, Jurgen R.; Schweinberger, Stefan R.

    2012-01-01

    Efficient processing of unfamiliar faces typically involves their categorization (e.g., into old vs. young or male vs. female). However, age and gender categorization may pose different perceptual demands. In the present study, we employed functional magnetic resonance imaging (fMRI) to compare the activity evoked during age vs. gender…

  11. 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…

  12. Data Resource Profile: The World Health Organization Study on global AGEing and adult health (SAGE)

    PubMed Central

    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; Yawson, A.; Mensah, G.; Yong, J.; Guo, Y.; Zheng, Y.; Parasuraman, P.; Lhungdim, H.; Sekher, TV.; Rosa, R.; Belov, VB.; Lushkina, NP; Peltzer, K.; Makiwane, M.; Zuma, K.; Ramlagan, S.; Davids, A.; Mbelle, N.; Matseke, G.; Schneider, M.; Tabane, C.; Tollman, S.; Kahn, K.; Ng, N.; Juvekar, S.; Sankoh, O.; Debpuur, CY.; Nguyen, TK Chuc; Gomez-Olive, FX.; Hakimi, M.; Hirve, S.; Abdullah, S.; Hodgson, A.; Kyobutungi, C.; Egondi, T.; Mayombana, C.; Minh, HV.; Mwanyangala, MA.; Razzaque, A.; Wilopo, S.; Streatfield, PK.; Byass, P.; Wall, S.; Scholten, F.; Mugisha, J.; Seeley, J.; Kinyanda, E.; Nyirenda, M.; Mutevedzi, P.; Newell, M-L.

    2012-01-01

    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). PMID:23283715

  13. 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).

  14. 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…

  15. 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.

  16. 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

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. Trajectories of Sleep Complaints From Early Midlife to Old Age: Longitudinal Modeling Study

    PubMed Central

    Salo, Paula; Vahtera, Jussi; Ferrie, Jane E.; Akbaraly, Tasnime; Goldberg, Marcel; Zins, Marie; Pentti, Jaana; Virtanen, Marianna; Shipley, Martin J.; Singh-Manoux, Archana; Dauvilliers, Yves; Kivimaki, Mika

    2012-01-01

    Study Objectives: To estimate trajectories of sleep lost over worry as a function of age, using longitudinal modeling, and compare these trajectories with those for insomnia symptoms. Design and Setting: Data from two prospective, occupational cohorts (the Whitehall II and Finnish Public Sector studies) comprising 84,384 observations from four to eight repeat measurements in 1985-2010. Participants: There were 16,408 men and women age 34-79 yr. Measurements and Results: Age-related trajectories of sleep lost over worry and insomnia symptoms (sleep initiation or maintenance problems, nonrefreshing sleep) were estimated using repeated-measures log-binomial regression analysis and generalized estimating equations. These analyses were adjusted for year of birth and time of measurement to minimize confounding by cohort or period effects. The prevalence ratio for insomnia symptoms was higher in older age groups compared with participants age 34-45 yr. In contrast, the age-related trajectory of sleep lost over worry included two phases: a period of high prevalence of sleep complaints at age 34-60 yr followed by a declining trajectory at older ages. Compared with participants age 34-45 yr, prevalence ratios for sleep lost over worry were 0.63 (0.49-0.80) and 0.59 (0.41-0.84) in the Whitehall II study participants ages 61-65 and 71-79 years. Corresponding figures were 0.62 (0.52-0.75) and 0.46 (0.32-0.66) in the Finnish Public Sector study. Conclusion: This study shows a general age-related decrease in sleep lost over worry between late midlife and old age, a pattern strikingly different from the age-related increase in insomnia symptoms. Citation: Salo P; Vahtera J; Ferrie JE; Akbaraly T; Goldberg M; Zins M; Pentti J; Virtanen M; Shipley MJ; Singh-Manoux A; Dauvilliers Y; Kivimaki M. Trajectories of sleep complaints from early midlife to old age: longitudinal modeling study. SLEEP 2012;35(11):1559-1568. PMID:23115405

  3. Age estimation using carpals: study of a Slovenian sample to test Cameriere's method.

    PubMed

    Cameriere, Roberto; Ferrante, Luigi; Ermenc, Branko; Mirtella, Dora; Strus, Katja

    2008-01-30

    Carpals are often used as age indicators. In a recent study, Cameriere et al. studied the use of the ratio between the total area of carpal bones and epiphyses of the ulna and radius (Bo) and carpals (Ca) as age indicators. The present study, of a sample of 158 Slovenian children and adolescents aged between 6 and 16 years, focused on analysing the best regression for age estimation. The regression model yielded the following equation: age=-3.411+0.942 g+20.927(Bo/Ca), and explained 91.6% of total variance (R(2)=0.916). The median of the absolute values of residuals (observed age minus predicted age) was 0.09 years, with a quartile deviation of 0.786 years, and a standard error of estimate of 0.658 years. Comparisons between the previous equation referring to Slovenian children and the equivalent linear equation proposed by Cameriere et al. did not reveal any significant differences between the intercepts and slopes of the two linear models. These results suggested a common regression model for both Italian and Slovenian samples. The common regression model, describing age as a linear function of gender and Bo/Ca ratio, yielded the following linear regression formula: age=-2.907+0.408 g+20.757(Bo/Ca). This model explained 86% of total variance (R(2)=0.86). The median of the absolute values of residuals (observed age minus predicted age) was 0.02 years, with a quartile deviation of 1.02 years and a standard error of estimate of 0.96 years.

  4. A developmental study of the own-age face recognition bias in children.

    PubMed

    Hills, Peter J

    2012-03-01

    The own-age bias is one in which people recognize faces of people their own age more accurately than faces of other ages (e.g., Anastasi & Rhodes, 2005, 2006) and appears to be, at least, partially based on experience (Harrison & Hole, 2009). Indeed, Hills and Lewis (2011a) have shown that 8-year-old faces are more accurately recognized by 8-year-old children than by 6- or 11-year-old children, suggesting the own-age bias develops rapidly. The present study explores the own-age bias in a developmental study in participants aged 6-10 years. Ninety participants (divided into 3 groups of 30 on the basis of their age at the first time of testing) undertook a standard old/new recognition paradigm in which their recognition accuracy was measured for 8- and 20-year-old faces. Results showed that when the participants were 8 years old, they recognized 8-year-old faces more accurately than when they were 7 or 9 years old. This effect was found to be based on mechanisms that differ from simple developmental improvement. This is the first study to show the development of the own-age bias in face recognition using a longitudinal design. These results show that the face recognition system is updated on the basis of recent experience and/or motivation to process faces, creating recognition biases.

  5. 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.

  6. 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).

  7. 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

  8. 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

  9. Little evidence for links between memory complaints and memory performance in very old age: longitudinal analyses from the Berlin Aging Study.

    PubMed

    Pearman, Ann; Hertzog, Christopher; Gerstorf, Denis

    2014-12-01

    Cross-sectional and longitudinal relationships between memory complaint and memory performance were examined in a sample of old-old participants from the Berlin Aging Study (BASE; N = 504, ages 70 to 100, age M = 84.7 at study onset). Participants were measured 4 times over the course of 6 years. Similar to many previous studies, initial cross-sectional memory complaints were predicted by depression and neuroticism, but not memory performance. Subjective age also predicted memory complaint independent of other variables. Latent growth curve models based on age and time in the study revealed that memory complaints did not change in level with age or time, and manifested no reliable random effects (individual differences in change). These models also detected no significant relationship between changes in memory and either initial memory complaint or changes in memory complaint over age or over time. None of the covariates that predicted initial memory complaints were related to changes in memory complaints over time. An autoregressive latent variable model for memory complaints, consistent with a conceptualization of complaints as judgments constructed from beliefs and other influences in the moment, did detect a concurrent effect of memory on memory complaints at the third occasion, controlling on initial complaints. These results suggest that for the oldest-old, changes in memory complaints may not primarily reflect monitoring of actual age-related memory changes, but rather are affected by other variables, including age-based memory stereotypes, neuroticism, depression, and concerns about aging.

  10. 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

  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. The influence of age on lip-line cant in adults: a cross-sectional study

    PubMed Central

    Choi, Sung Hwan; Kim, Jung Suk; Kim, Cheol Soon

    2016-01-01

    Objective The aims of this study were to assess the direction and degree of lip-line cant in Korean adult orthodontic patients and to identify the effects of sex and age on changes in the cant severity. Methods In this cross-sectional retrospective study, lip-line cant was measured in the frontal photographs of 585 Korean patients (92 men and 493 women) aged 18-48 years. The outcome variables (direction and degree of lip-line cant) were assessed in terms of predictor variables (sex, age, sagittal skeletal relationship, and menton deviation angle). Results The direction of lip-line cant did not differ according to sex, age, or skeletal classification. Patients had 1.6° of lip-line cant on average before orthodontic treatment. Middle-aged adults displayed a significant trend toward a lower degree of lip-line cant compared to younger adults (p < 0.01). Multiple linear regression analysis showed that the degree of lip-line cant was weakly negatively correlated with age (p < 0.001). Conclusions While the direction of lip-line cant did not differ according to the parameters explored here, the degree of cant was correlated with age in adults, independent of menton deviation. Specifically, middle-aged adults tended to display significantly lower degrees of lip-line cant than did younger adults. PMID:27019822

  13. The Classical Conditioning of Attitudes: A Comparative Study of Ages 8 to 18

    ERIC Educational Resources Information Center

    O'Donnell, John M.; Brown, Mari J. K.

    1973-01-01

    Results of this study indicated that attitude conditioning increased with age and that the increase appeared to be a function of contingency awareness and perhaps also a function of the older subjects' having greater facility in transferring symbolic meaning. (Author)

  14. Aging process on spectrally determined spontaneous baroreflex sensitivity: a 5-year prospective study.

    PubMed

    Fauvel, Jean-Pierre; Cerutti, Catherine; Mpio, Ignace; Ducher, Michel

    2007-09-01

    The interindividual age-related decrease in baroreflex sensitivity (BRS) was reported in many cross-sectional studies. However, the long-term intraindividual decrease in BRS has never been confirmed by longitudinal studies. Data obtained from a 5-year prospective study designed to assess the 5-year stress effects on blood pressure (BP) provided the opportunity to assess longitudinal aging process on spectrally determined BRS (S-BRS) using the cross spectral analysis. This analysis was carried out in 205 men aged between 18 and 50 years who had 2 valid beat to beat BP recordings (Finapress) at a mean 5-year interval. At inclusion and at end of follow-up, S-BRS was significantly correlated with age (r=-0.50, P<0.001, r=-0.33, P<0.001 respectively). Interestingly, the slopes and the intercepts were not significantly different at a 5-year interval. This result is in favor of the good reproducibility of S-BRS. The attenuation with age of S-BRS was calculated at 3.6% a year. This decrease was slightly higher than the one obtained with the baseline data (2.3% per year). This longitudinal study provided, for the first time, an estimate of the slope of the age-related physiological S-BRS decrease in a mid-aged healthy male population. Our findings reinforce the interest of evaluating spontaneous BRS reported to predict hypertension and cardiovascular events in various populations.

  15. The Werner syndrome. A model for the study of human aging.

    PubMed

    Nehlin, J O; Skovgaard, G L; Bohr, V A

    2000-06-01

    Human aging is a complex process that leads to the gradual deterioration of body functions with time. Various models to approach the study of aging have been launched over the years such as the genetic analysis of life span in the yeast S. cerevisiae, the worm C. elegans, the fruitfly, and mouse, among others. In human models, there have been extensive efforts using replicative senescence, the study of centenerians, comparisons of young versus old at the organismal, cellular, and molecular levels, and the study of premature aging syndromes to understand the mechanisms leading to aging. One good model for studying human aging is a rare autosomal recessive disorder known as the Werner syndrome (WS), which is characterized by accelerated aging in vivo and in vitro. A genetic defect implicated in WS was mapped to the WRN locus. Mutations in this gene are believed to be associated, early in adulthood, with clinical symptoms normally found in old individuals. WRN functions as a DNA helicase, and recent evidence, summarized in this review, suggests specific biochemical roles for this multifaceted protein. The interaction of WRN protein with RPA (replication protein A) and p53 will undoubtedly direct efforts to further dissect the genetic pathway(s) in which WRN protein functions in DNA metabolism and will help to unravel its contribution to the human aging process.

  16. Melatonin has differential effects on age-induced stoichiometric changes in daily chronomics of serotonin metabolism in SCN of male Wistar rats.

    PubMed

    Reddy, M Y; Jagota, Anita

    2015-06-01

    Suprachiasmatic nucleus (SCN) controls various physiological, endocrine and behavioral functions by regulating conversion of serotonin (5-HT) to melatonin (MEL). Aging leads to alterations in the neural and temporal organization of the SCN leading to circadian dysfunction. Age-induced stoichiometric alterations in daily chronomics of various components of 5-HT metabolism were studied by constructing interactomes between parameters. The levels of tryptophan (TRP), 5-hydroxytryptophan (5-HTP), 5-hydroxytryptamine (5-HT), N-acetylserotonin (NAS), N-acetyl 5-methoxytryptamine (MEL), 5-hydroxyindoleacetic acid (5-HIAA), 5-methoxyindole acetic acid (5-MIAA), 5-hydroxytryptophol (5-HTOH), 5-methoxytryptophol (5-MTOH) and N-acetyltryptamine (NAT) were measured at (Zeitgeber time 0, 6, 12 and 18) in male rat SCN of 3, 12 and 24 months age groups. Age-induced decrease was observed in mean levels of NAS, MEL, 5-HIAA, 5-MIAA, 5-MTOH, and NAT and increase was observed in TRP, 5-HTP, 5-HT and 5-HTOH in rat SCN. Daily pulses decreased with aging significantly for TRP, 5-HT, NAS, MEL, 5-HIAA, 5-MIAA and NAT. We report here, the age-induced change in interactions between various 5-HT metabolism components by middle age (12 m) changing further by 24 m. The daily rhythms persisted with aging for NAS, MEL and 5-HTOH. Though, rhythms were abolished for TRP, 5-HTP, 5-HIAA, 5-MIAA, 5-MTOH and NAT differentially at 12 and 24 m. The MEL administration showed restoration in 5-HT ratio with 5-HTP, MEL and 5-HTOH in 24 m and NAS and 5-HIAA in 12 m SCN. Thus, MEL administration effects alterations of age-induced stoichiometry in levels and chronomics of serotonin metabolic network interactomes.

  17. 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. PMID:26146887

  18. Glycated Reconstructed Human Skin as a Platform to Study the Pathogenesis of Skin Aging.

    PubMed

    Pennacchi, Paula Comune; de Almeida, Maíra Estanislau Soares; Gomes, Octávio Luís Alves; Faião-Flores, Fernanda; de Araújo Crepaldi, Maria Clara; Dos Santos, Marinilce Fagundes; de Moraes Barros, Silvia Berlanga; Maria-Engler, Silvya Stuchi

    2015-09-01

    The advanced glycation end products (AGEs) of proteins are common factors in the pathophysiology of a number of disorders related to aging. The skin generation of AGEs occurs mainly through nonenzymatic glycation reactions of extracellular matrix (ECM) proteins in the dermis. The AGEs have been touted as one of the factors responsible for healing impairment and loss of elasticity of healing skin, affecting growth, differentiation, and cellular motility, as well as cytokines response, metalloproteinases expression, and vascular hemostasis. In this study, we generated an in vitro full-thickness reconstructed skin based on a glycated collagen matrix dermal compartment to evaluate the effects of glycation on dermal ECM and ultimately on the epidermis. Epidermal differentiation and stratification patterns and the glycation-induced ECM changes were evaluated by histology, immunohistochemistry, and mRNA levels. In this study, we reported for the first time that changes in the dermal matrix caused by collagen I in vitro glycation processes also affect the epidermal compartment. We demonstrated that glycation of collagen induces expression of carboxymethyllysine in dermal and epidermal compartments and, consequently, an aging phenotype consisting of poor stratification of epidermal layers and vacuolization of keratinocyte cytoplasm. Increased expression of cell-cell adhesion markers, such as desmoglein and E-cadherin in glycated skins, is observed in the stratum spinosum, as well as an increased compression of dermal collagen matrix. We also submitted our 3D model of reconstructed glycated skin to screening of anti-AGE molecules, such as aminoguanidine, which prevented the glycated morphological status. Controlled human studies investigating the effects of anti-AGE strategies against skin aging are largely missing. In this context, we proposed the use of skin equivalents as an efficient model to investigate cellular interactions and ECM changes in the aging skin, and to

  19. Glycated Reconstructed Human Skin as a Platform to Study the Pathogenesis of Skin Aging.

    PubMed

    Pennacchi, Paula Comune; de Almeida, Maíra Estanislau Soares; Gomes, Octávio Luís Alves; Faião-Flores, Fernanda; de Araújo Crepaldi, Maria Clara; Dos Santos, Marinilce Fagundes; de Moraes Barros, Silvia Berlanga; Maria-Engler, Silvya Stuchi

    2015-09-01

    The advanced glycation end products (AGEs) of proteins are common factors in the pathophysiology of a number of disorders related to aging. The skin generation of AGEs occurs mainly through nonenzymatic glycation reactions of extracellular matrix (ECM) proteins in the dermis. The AGEs have been touted as one of the factors responsible for healing impairment and loss of elasticity of healing skin, affecting growth, differentiation, and cellular motility, as well as cytokines response, metalloproteinases expression, and vascular hemostasis. In this study, we generated an in vitro full-thickness reconstructed skin based on a glycated collagen matrix dermal compartment to evaluate the effects of glycation on dermal ECM and ultimately on the epidermis. Epidermal differentiation and stratification patterns and the glycation-induced ECM changes were evaluated by histology, immunohistochemistry, and mRNA levels. In this study, we reported for the first time that changes in the dermal matrix caused by collagen I in vitro glycation processes also affect the epidermal compartment. We demonstrated that glycation of collagen induces expression of carboxymethyllysine in dermal and epidermal compartments and, consequently, an aging phenotype consisting of poor stratification of epidermal layers and vacuolization of keratinocyte cytoplasm. Increased expression of cell-cell adhesion markers, such as desmoglein and E-cadherin in glycated skins, is observed in the stratum spinosum, as well as an increased compression of dermal collagen matrix. We also submitted our 3D model of reconstructed glycated skin to screening of anti-AGE molecules, such as aminoguanidine, which prevented the glycated morphological status. Controlled human studies investigating the effects of anti-AGE strategies against skin aging are largely missing. In this context, we proposed the use of skin equivalents as an efficient model to investigate cellular interactions and ECM changes in the aging skin, and to

  20. Nylon 6.6 accelerated aging studies : thermal-oxidative degradation and its interaction with hydrolysis.

    SciTech Connect

    Bernstein, Robert; Derzon, Dora Kay; Gillen, Kenneth T.

    2004-06-01

    Accelerated aging of Nylon 6.6 fibers used in parachutes has been conducted by following the tensile strength loss under both thermal-oxidative and 100% relative humidity conditions. Thermal-oxidative studies (air circulating ovens) were performed for time periods of weeks to years at temperatures ranging from 37 C to 138 C. Accelerated aging humidity experiments (100% RH) were performed under both an argon atmosphere to examine the 'pure' hydrolysis pathway, and under an oxygen atmosphere (oxygen partial pressure close to that occurring in air) to mimic true aging conditions. As expected the results indicated that degradation caused by humidity is much more important than thermal-oxidative degradation. Surprisingly when both oxygen and humidity were present the rate of degradation was dramatically enhanced relative to humidity aging in the absence of oxygen. This significant and previously unknown phenomena underscores the importance of careful accelerated aging that truly mimics real world storage conditions.

  1. A connection between magnesium deficiency and aging: new insights from cellular studies.

    PubMed

    Killilea, David W; Maier, Jeanette A M

    2008-06-01

    Most human cells can only replicate a limited number of times in cultures before they lose the ability to divide, a phenomenon known as replicative senescence, which seems to play a role in aging at the organismal level. Recent studies have shown that culture in low magnesium (Mg) accelerates the senescence of human endothelial cells and fibroblasts. Given the numerous critical roles of Mg, it seems likely that Mg inadequacy would interfere with cellular metabolism, which could affect the senescence process. Since i) several pieces of evidence link low Mg to aging and age-related diseases and ii) the Occidental diet is relatively deficient in Mg, we propose that broadly correcting nutritional intakes of Mg might contribute to healthier aging and the prevention of age-related diseases.

  2. The influence of gender and age on disability following ischemic stroke: the Framingham study.

    PubMed

    Kelly-Hayes, Margaret; Beiser, Alexa; Kase, Carlos S; Scaramucci, Amy; D'Agostino, Ralph B; Wolf, Philip A

    2003-01-01

    The magnitude of disability among elderly stroke survivors is substantial. There have been few community-based estimates of the contribution gender and older age make to stroke-related disability and outcome. Using the original Framingham Study cohort, we documented gender-specific neurological deficits and disability differences in stroke survivors at six months post-stroke. Logistic regression analyses were performed to estimate odds ratios, comparing men and women, and adjusting for age, and age and stroke subtype. Age and gender-matched controls were then compared to distinguish stroke-related disability from disability associated with general aging. Results showed that almost half (43%) of all elderly stroke survivors in the cohort had moderate to severe neurological deficits. In the crude analyses, women were more dependent in ADLs (33.9% vs 15.6%), less likely to walk unassisted (40.3% vs 17.8%), and living in nursing homes (34.9 % vs 13.3%). After adjusting for age and stroke subtype, it was older age that accounted for the severity of disability. When compared to age and gender-matched controls, stroke cases were significantly more disabled in all domains studied. In this elderly cohort, more women experienced initial strokes and were more disabled at 6 months post-stroke than men. However, older age at stroke onset, not gender or stroke subtype, was associated with greater disability. Health care providers need to understand that strokes occur later in life for women and that because of age, women are at greater risk for disability and institutionalization.

  3. NMR Studies of Cu/zeolite SCR Catalysts Hydrothermally Aged with Urea

    SciTech Connect

    Cheng, Yisun; Hoard, John; Lambert, Christine; Kwak, Ja Hun; Peden, Charles HF

    2008-06-26

    The effects of hydrothermal aging of Cu/zeolite urea-SCR catalysts on their reactivity and material properties was assessed by performance tests and multiple characterization techniques that included 27Al NMR and XRD. Three aging protocols were used that consisted of varying temperature during hydrothermal aging with or without exposure to aqueous urea solution. Differences in behavior were even found for samples hydrothermally aged immediately following exposure to the urea solution or if the sample was dried overnight before hydrothermal aging. The combination of urea and high temperature exposure increased the deactivation of Cu/zeolite SCR catalysts beyond that observed by hydrothermal aging alone, with an immediate high temperature exposure following wetting of the catalyst core with aqueous urea causing the most significant deterioration in performance. The impact of urea on SCR catalyst durability was also found to increase with the aging temperature. NMR analysis suggested that aging with urea resulted in relatively more dealumination of the zeolite for the SCR catalysts in this study.

  4. Ultrasound determination of gestational age using placental thickness in female dogs: an experimental study.

    PubMed

    Maldonado, André Luiz Louzada; Araujo Júnior, Edward; Mendonça, Débora Sartori; Nardozza, Luciano Marcondes Machado; Moron, Antonio Fernandes; Ajzen, Sérgio Aron

    2012-01-01

    Objective. To verify if the placental thickness allows determining the gestational age, evaluating the correlation between the referred gestational age with the studied one, and the accuracy of the placental thickness measurement (biometry) with fetal morphologic parameters in bitches. Methods. The placental thickness of 336 bitches of diverse breeds was evaluated. Bitches were divided in three groups by body weight: small, medium, and big large size. The gestations pregnancies were evaluated by ultrasound from the third week of gestation. An analysis was performed between the mean values of the gestational age obtained of placental thickness by adjustment of curves and the reported gestational age. Student's t-test was applied to compare the mean of reported and placental thickness gestational age. Significance was defined as P < 0.05. Results. A positive and statistically significant correlation exists between the placental thickness and gestational age. The expression that presents the best correlation coefficient and explanation was thickness of placenta = 0.021x gestational age -0.314. Conclusion. It is possible to determine the gestational age in relation to the placental thickness measured by ultrasound in bitches with a satisfactory accuracy in relation to fetal morphologic parameters as gestational vesicle, ribs, or kidneys. PMID:22848867

  5. Ultrasound Determination of Gestational Age Using Placental Thickness in Female Dogs: An Experimental Study

    PubMed Central

    Maldonado, André Luiz Louzada; Araujo Júnior, Edward; Mendonça, Débora Sartori; Nardozza, Luciano Marcondes Machado; Moron, Antonio Fernandes; Ajzen, Sérgio Aron

    2012-01-01

    Objective. To verify if the placental thickness allows determining the gestational age, evaluating the correlation between the referred gestational age with the studied one, and the accuracy of the placental thickness measurement (biometry) with fetal morphologic parameters in bitches. Methods. The placental thickness of 336 bitches of diverse breeds was evaluated. Bitches were divided in three groups by body weight: small, medium, and big large size. The gestations pregnancies were evaluated by ultrasound from the third week of gestation. An analysis was performed between the mean values of the gestational age obtained of placental thickness by adjustment of curves and the reported gestational age. Student's t-test was applied to compare the mean of reported and placental thickness gestational age. Significance was defined as P < 0.05. Results. A positive and statistically significant correlation exists between the placental thickness and gestational age. The expression that presents the best correlation coefficient and explanation was thickness of placenta = 0.021x gestational age −0.314. Conclusion. It is possible to determine the gestational age in relation to the placental thickness measured by ultrasound in bitches with a satisfactory accuracy in relation to fetal morphologic parameters as gestational vesicle, ribs, or kidneys. PMID:22848867

  6. 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

  7. Variations in pulp/tooth area ratio as an indicator of age: a preliminary study.

    PubMed

    Cameriere, Roberto; Ferrante, Luigi; Cingolani, Mariano

    2004-03-01

    This paper details a method for age determination of adults from single rooted teeth. The sample consisted of 100 Italian white Caucasian patients (46 men, 54 women) aged between 18 and 72 years. The single rooted maxillary right canine was utilized in this preliminary study. Pulp/root ration, tooth length, pulp/tooth length ratio, pulp/tooth area and pulp/root width ratios at three different levels were computed. Pearson's correlation coefficients between age and these variables showed that the ratio between pulp and tooth area correlated best with age (r2 = 0.85). Stepwise multiple regression models yielded a linear relationship between pulp/root width at mid-root level and chronological age and a linear relationship when pulp/tooth area was compared to age. Statistical analysis indicated that these two variables explain 84.9% of variations in estimated chronological age. The median of the absolute value of residual errors between actual and estimated ages was less than four years.

  8. 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

  9. 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

  10. 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…

  11. 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. PMID:26698388

  12. 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.

  13. Thyroid function, depressed mood, and cognitive performance in older individuals: the Maastricht Aging Study.

    PubMed

    van Boxtel, M P J; Menheere, P P C A; Bekers, O; Hogervorst, E; Jolles, J

    2004-08-01

    The hypothesis was tested that thyroid function, as indicated by serum thyroid-stimulating hormone (TSH) level, is associated with cognitive performance in a healthy aging population. In a random sample of 120 participants recruited from the Maastricht Aging Study (MAAS), aged between 49 and 71 years, we assessed TSH level, mood state (Symptom Check List, subscale depression), and three domains of cognitive function: verbal memory, general sensorimotor speed, and complex flexibility. After correction for age, sex, and educational level, a negative association between TSH and memory function was apparent: higher levels of TSH predicted lower levels of memory performance. Exclusion of individuals with TSH levels suspect for thyroid disorder (n=2) or who were on thyroid replacement (n=3) attenuated this association. Furthermore, additional control for mood status reduced the association below the significance level. No interaction between age and TSH on cognition was found, which indicated that the TSH-memory association was independent of age group level. We conclude that the association between TSH level and memory performance was small and dependent on mood status and the presence of (possible) thyroid disease in this relatively healthy population based sample. Prospective studies are needed to address the role of thyroid function in age-related cognitive decline.

  14. An Age-Friendly Living Environment as Seen by Chinese Older Adults: A "Photovoice" Study.

    PubMed

    Chan, Aileen W K; Chan, Helen Y L; Chan, Ivy K Y; Cheung, Bonnie Y L; Lee, Diana T F

    2016-01-01

    "Ageing in place" is a policy initiative strongly advocated by the World Health Organization to face the challenge of an ageing population. This pilot study used a "photovoice" approach, aiming to explore aspects of the housing environment considered by older people as important in facilitating ageing in place. It enabled participants to express their ideas through photographs. Each participant was asked to take photos that illustrated age-friendly features they considered crucial for supporting their lives in the community. A total of 44 older people participated in the pilot study, and 300 photos were collected. Participants were invited to describe the reasons for taking these photos by filling in a journal sheet. A semi-structured interview was then conducted with individual participants, who were asked to elaborate on the meaning of their photos. The analysis revealed three themes: (1) age-friendly housing design; (2) supportive neighborhood; and (3) connection to family and the community. These three themes are pillars of an age-friendly city, which are important to seniors to facilitate ageing in place. PMID:27649217

  15. Age at menarche and risk of ovarian cancer: a meta-analysis of epidemiological studies.

    PubMed

    Gong, Ting-Ting; Wu, Qi-Jun; Vogtmann, Emily; Lin, Bei; Wang, Yong-Lai

    2013-06-15

    Epidemiological studies have reported inconsistent associations between menarcheal age and ovarian cancer risk. To our knowledge, a meta-analysis for the association between menarcheal age and ovarian cancer has not been reported. Relevant published studies of menarcheal age and ovarian cancer were identified using MEDLINE, EMBASE and Web of Science through the end of April 2012. Two authors (T-T.G. and Q-J.W.) independently assessed eligibility and extracted data. We pooled the relative risks (RRs) from individual studies using a random-effects model and performed heterogeneity and publication bias analyses. A total of 27 observational studies consisting of 22 case-control and five cohort studies were included in our analysis. In a pooled analysis of all studies, a statistically significant inverse association was observed between menarcheal age (for the oldest compared to the youngest category) and ovarian cancer risk (RR = 0.85; 95% confidence interval [CI] = 0.75-0.97). The pooled RRs of ovarian cancer for the oldest versus the youngest categories of menarcheal age in prospective and case-control studies were 0.89 (95% CI = 0.76-1.03) and 0.84 (95% CI = 0.70-0.99), respectively. Inverse associations between menarcheal age and ovarian cancer risk were observed in most subgroups; however, the significant association was restricted to invasive and borderline serous ovarian cancer. In conclusion, findings from this meta-analysis support that menarcheal age was inversely associated with the risk of ovarian cancer. More large studies are warranted to stratify these results by different cancer grading and histotype of ovarian cancer.

  16. 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),…

  17. [Comparative study of 2 groups of paranoid syndromes appearing at different ages].

    PubMed

    Gilliéron, E; Müller, C

    1976-01-01

    Clinical study of two groups of females beyond age of 65, institutionalized for delusional manifestations of schizophrenic nature and presenting also, at the time of examination, a pronounced paranoid state. In the first group: the manifestations had arisen before the age of 45. In the second group, after the age of 65. This study has demonstrated certain psychopathological characteristics suggesting the presence of personality problems definitely more profound in patients of the first group: autistic state, asthenia, thought disorder, incoherence and vagueness of delusional subjects, ordinarily much more unreal are characteristics of the first group in comparison to the second. This seems to bring evidence that these two paranoid states (paranoid schizophrenia in adult age and paranoid state in senility) are, at first sight, pathological entities based on personality problems of very different intensity.

  18. Assessment of Dental Age of Children Aged 3.5 to 16.9 Years Using Demirjian’s Method: A Meta-Analysis Based on 26 Studies

    PubMed Central

    Yan, Jin; Lou, Xintian; Xie, Liming; Yu, Dedong; Shen, Guofang; Wang, Yilin

    2013-01-01

    Background A method for assessing dental maturity in different populations was first developed in 1973 by Demirjian and has been widely used and accepted since then. While the accuracy for evaluating dental age using Demirjian’s method compared to children’s chronological age has been extensively studied in recent years, the results currently available remain controversial and ambiguous. Methods A literature search of PubMed, Embase, Web of Science, CNKI and CBM databases was conducted to identify all eligible studies published before July 12th, 2013. Weighted mean difference (WMD) with corresponding 95% confidence interval (95% CI) was used to evaluate the applicability of Demirjian’s method for estimating chronological age in children. Results: A meta-analysis was conducted on 26 studies with a total of 11,499 children (5,301 boys and 6,198 girls) aged 3.5 to 16.9 years. Overall, we found that Demirjian’s method overestimated dental age by 0.35 (4.2 months) and 0.39 (4.68 months) years in males and females, respectively. A subgroup analysis by age revealed that boys and girls between the ages of 5 to 14 were given a dental age estimate that was significantly more advanced than their chronological age. Differences between underestimated dental ages and actual chronological ages were lower for male and female 15- and 16-year-old subgroups, though a significant difference was found in the 16-year-old subgroup. Conclusions Demirjian’s method’s overestimation of actual chronological tooth age reveals the need for population-specific standards to better estimate the rate of human dental maturation. PMID:24367690

  19. 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

  20. Ubiquity and Diversity of Heterotrophic Bacterial nasA Genes in Diverse Marine Environments

    PubMed Central

    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

  1. 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

  2. Accelerated changes in white matter microstructure during aging: a longitudinal diffusion tensor imaging study.

    PubMed

    Sexton, Claire E; Walhovd, Kristine B; Storsve, Andreas B; Tamnes, Christian K; Westlye, Lars T; Johansen-Berg, Heidi; Fjell, Anders M

    2014-11-12

    It is well established that human brain white matter structure changes with aging, but the timescale and spatial distribution of this change remain uncertain. Cross-sectional diffusion tensor imaging (DTI) studies indicate that, after a period of relative stability during adulthood, there is an accelerated decline in anisotropy and increase in diffusivity values during senescence; and, spatially, results have been discussed within the context of several anatomical frameworks. However, inferring trajectories of change from cross-sectional data can be challenging; and, as yet, there have been no longitudinal reports of the timescale and spatial distribution of age-related white matter change in healthy adults across the adult lifespan. In a longitudinal DTI study of 203 adults between 20 and 84 years of age, we used tract-based spatial statistics to characterize the pattern of annual change in fractional anisotropy, axial diffusivity, radial diffusivity, and mean diffusivity and examined whether there was an acceleration of change with age. We found extensive and overlapping significant annual decreases in fractional anisotropy, and increases in axial diffusivity, radial diffusivity, and mean diffusivity. Spatially, results were consistent with inferior-to-superior gradients of lesser-to-greater vulnerability. Annual change increased with age, particularly within superior regions, with age-related decline estimated to begin in the fifth decade. Charting white matter microstructural changes in healthy aging provides essential context to clinical studies, and future studies should compare age trajectories between healthy participants and at-risk populations and also explore the relationship between DTI rates of change and cognitive decline.

  3. 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…

  4. 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

  5. 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

  6. Slow dynamics and aging in colloidal gels studied by x-ray photon correlation spectroscopy

    SciTech Connect

    Fluerasu, Andrei; Moussaied, Abdellatif; Madsen, Anders; Schofield, Andrew

    2007-07-15

    Slow, nonequilibrium dynamics during delayed sedimentation in a colloidal depletion gel was studied by x-ray photon correlation spectroscopy. The intermediate scattering functions change during the process from stretched to compressed exponential decays, indicating a jamming transition toward full aging. A complex aging behavior follows this process; it is proposed that large-scale network deformations trigger an unjamming, leading to the final collapse of the gel.

  7. 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.

  8. 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. PMID:22087271

  9. 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

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

    PubMed

    Sundberg, J P; Berndt, A; Sundberg, B A; Silva, K A; Kennedy, V; Smith, R S; Cooper, T K; Schofield, P N

    2016-03-01

    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 analytic tools that are available. A large-scale aging study was conducted on 28 inbred strains representing great genetic diversity to determine, via histopathology, the type and diversity of spontaneous diseases that aging mice develop. A total of 20 885 different diagnoses were made, with an average of 12 diagnoses per mouse in the study. Eighteen inbred strains have had their genomes sequenced, and many others have been partially sequenced to provide large repositories of data on genetic variation among the strains. This vast amount of genomic information can be utilized in genome-wide association studies to find candidate genes that are involved in the pathogenesis of spontaneous diseases. As an illustration, this article presents a genome-wide association study of the genetic associations of age-related intestinal amyloidosis, which implicated 3 candidate genes: translocating chain-associated membrane protein 1 (Tram1); splicing factor 3b, subunit 5 (Sf3b5); and syntaxin 11 (Stx11). 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. Many of the age-related mouse diseases are similar, if not identical, to human diseases; therefore, the genetic discoveries have direct translational benefit. PMID:26936752

  11. 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. PMID:24776689

  12. Comparative review of studies on aging effects in context of biometric authentication

    NASA Astrophysics Data System (ADS)

    Scheidat, Tobias; Heinze, Juliane; Vielhauer, Claus; Dittmann, Jana; Kraetzer, Christian

    2011-02-01

    The performance of a biometric system from the point of view of authentication, enrollment and usability depends not only on the algorithms, hardware and software used, but also on aging effects of the human body. Thus, the examination of the influence of ageing depended physiological and mental variances of potential user groups is an important part of biometric research. In this paper a survey of studies is presented which examining effects of biological aging on enrollment and authentication performance as well as usability of biometric systems based on modalities fingerprint, face and iris. In order to compare the findings of the studies and overcome the problem, that nearly every one of these studies uses its own database with varying number of users and different sensors, measurements and/or aging levels, we developed a novel graphical representation of the results. It provides an overview of changes appearing with increasing age and possible influences on performance or usability. The outcomes of a high number of evaluations are compared for each of the three biometric modalities in context of aging and finally concluded in the novel graphical representation.

  13. [Longitudinal change in independence in the elderly--Kahoku Longitudinal Aging Study (KLAS)].

    PubMed

    Matsubayashi, K; Okumiya, K; Kawamoto, A; Kimura, S; Wada, T; Fujisawa, M; Doi, Y; Shimada, K; Ozawa, T

    1994-10-01

    A community based study named Kahoku Longitudinal Aging Study (KLAS) was conducted since 1990 for the purpose of evaluating the comprehensive geriatric functional assessment (CGA) and preventing a decline in CGA in the community-dwelling elderly population. It was carried out in a Japanese rural town, in which 32% of the population was over 65 years of age. This study included a questionnaire about activity of daily living (ADL), information-related physical function, mental (cognitive and affective) and social functional domains. In addition to subjective informative instruments, various types of objective assessment such as quantitative neuro-behavioral function tests and medical examinations were performed. Subjects were all the eligible elderly aged over 65 years in the community. Although the ratio of subjects who were independent in ADL decreased with advancing age in both 1991 and 1993, the ratio of the independent elderly in ADL became significant higher (74%) in 1993 than in 1991 (71%). Scores on 2 kinds of neurobehavioral function tests in the 159 subjects aged over 75 years who attended the examination every year showed a significant and slight decrease during two years. However, some test indices significantly improved during the 2 years. These results suggested that age-related dependency in ADL and some kind of neurobehavioral functions might be prevented, in part, by health promoting education and improvement of life style. PMID:7853739

  14. Factors affecting longitudinal trajectories of plasma sphingomyelins: the Baltimore Longitudinal Study of Aging

    PubMed Central

    Mielke, Michelle M; Bandaru, Veera Venkata Ratnam; Han, Dingfen; An, Yang; Resnick, Susan M; Ferrucci, Luigi; Haughey, Norman J

    2015-01-01

    Sphingomyelin metabolism has been linked to several diseases and to longevity. However, few epidemiological studies have quantified individual plasma sphingomyelin species (identified by acyl-chain length and saturation) or their relationship between demographic factors and disease processes. In this study, we determined plasma concentrations of distinct sphingomyelin species in 992 individuals, aged 55 and older, enrolled in the Baltimore Longitudinal Study of Aging. Participants were followed, with serial measures, up to 6 visits and 38 years (3972 total samples). Quantitative analyses were performed on a high-performance liquid chromatography-coupled electrospray ionization tandem mass spectrometer. Linear mixed models were used to assess variation in specific sphingomyelin species and associations with demographics, diseases, medications or lifestyle factors, and plasma cholesterol and triglyceride levels. We found that most sphingomyelin species increased with age. Women had higher plasma levels of all sphingomyelin species and showed steeper trajectories of age-related increases compared to men. African Americans also showed higher circulating sphingomyelin concentrations compared to Caucasians. Diabetes, smoking, and plasma triglycerides were associated with lower levels of many sphingomyelins and dihydrosphingomyelins. Notably, these associations showed specificity to sphingomyelin acyl-chain length and saturation. These results demonstrate that longitudinal changes in circulating sphingomyelin levels are influenced by age, sex, race, lifestyle factors, and diseases. It will be important to further establish the intra-individual age- and sex-specific changes in each sphingomyelin species in relation to disease onset and progression. PMID:25345489

  15. Demirjian's method in the estimation of age: A study on human third molars

    PubMed Central

    Lewis, Amitha J.; Boaz, Karen; Nagesh, K. R; Srikant, N; Gupta, Neha; Nandita, K. P; Manaktala, Nidhi

    2015-01-01

    Aim: The primary aim of the following study is to estimate the chronological age based on the stages of third molar development following the eight stages (A to H) method of Demirjian et al. (along with two modifications-Orhan) and secondary aim is to compare third molar development with sex and age. Materials and Methods: The sample consisted of 115 orthopantomograms from South Indian subjects with known chronological age and gender. Multiple regression analysis was performed with chronological age as the dependable variable and third molar root development as independent variable. All the statistical analysis was performed using the SPSS 11.0 package (IBM ® Corporation). Results: Statistically no significant differences were found in third molar development between males and females. Depending on the available number of wisdom teeth in an individual, R2 varied for males from 0.21 to 0.48 and for females from 0.16 to 0.38. New equations were derived for estimating the chronological age. Conclusion: The chronological age of a South Indian individual between 14 and 22 years may be estimated based on the regression formulae. However, additional studies with a larger study population must be conducted to meet the need for population-based information on third molar development. PMID:26005306

  16. 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.

  17. 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. PMID:17364561

  18. Accelerated aging studies of UHMWPE. II. Virgin UHMWPE is not immune to oxidative degradation.

    PubMed

    Edidin, A A; Villarraga, M L; Herr, M P; Muth, J; Yau, S S; Kurtz, S M

    2002-08-01

    In Part I of this series, we showed that aging at elevated oxygen pressure is more successful at increasing the depth to which degradation occurs although it, too, generally causes greater degradation at the surface than at the subsurface. Therefore we hypothesized that thermal degradation alone, in the absence of free radicals, could be sufficient to artificially age UHMWPE in a manner analogous to natural aging. In the present study, virgin and air-irradiated UHMWPE (extruded GUR 1050 and compression-molded 1900) were aged up to 4 weeks at elevated oxygen pressure, and the mechanical behavior at the surface and subsurface was examined. All the materials were substantially degraded following 4 weeks of aging, but the spatial variations in the nonirradiated materials more closely mimicked the previously observed subsurface peak of degradation seen in naturally aged UHMWPE following irradiation in air. This aged material could provide a more realistic model for subsurface mechanical degradation, making it suitable for further mechanical testing in venues such as wear simulation.

  19. 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.

  20. Fluorescence intensity of resin composites and dental tissues before and after accelerated aging: a comparative study.

    PubMed

    Takahashi, Marcos Kenzo; Vieira, Sergio; Rached, Rodrigo Nunes; de Almeida, Janaina Bertoncelo; Aguiar, Marcelo; de Souza, Evelise Machado

    2008-01-01

    This study quantitatively evaluated the fluorescence intensity of resin composites with different opacities and translucencies and determined changes in fluorescence after accelerated aging, using human enamel and dentin as controls. Six microhybrid and nanofilled composites, each in three different shades, were tested. Ten sound human incisors were used to obtain enamel and dentin specimens separately. Fluorescence measurements were obtained with a fluorescence spectrophotometer before (baseline) and after accelerated aging at 150 kJ energy for 120 hours. One-way analysis of variance (ANOVA) and Games-Howell multiple comparison tests were performed at a significance level of 0.05. Student's t-test was also used for comparison before and after aging. At baseline, there was no statistically significant difference (p>0.05) between the fluorescence intensity of dentin and any of the shades of Charisma or Opallis, Esthet-X dentin shade or Vit-l-escence enamel, or the translucent shades. After accelerated aging, all shades of the 4 Seasons, enamel and the translucent shades of Esthet-X had fluorescence intensities statistically similar to that of aged dentin (p>0.05). A significant reduction in fluorescence after aging (p<0.05) was observed for all the materials, except for human enamel and translucent Filtek Supreme XT. Accelerated aging reduced fluorescence in most of the composites evaluated.

  1. 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 focus on…

  2. 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.

  3. 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.

  4. [Health and ageing: a study of Brazilian masters dissertations (2000-2009)].

    PubMed

    Hein, Mariana Almeida; Aragaki, Sérgio Seiji

    2012-08-01

    The scope of this study was to understand the current discursive practices and meanings that have been produced about the relationship between health and ageing. The study was based on abstracts of dissertations available in the CAPES (Coordination of Personal of Higher Education) portal between 2000 and 2009, accessed by using the following search words: aged, ageing, old age, senescence, the elderly and old people. Based on the material selected, 175 abstracts of papers, in-depth readings were made and analytical categories created. The conclusion was reached that there are several terms used to designate the people in the life cycle under scrutiny: the elderly, old people and senior citizens, with predominance of the first. Although there is still a negative connotation related to the elderly and ageing, this is changing. Several meanings are possible and coexist, forged in accordance with historical, social, economic and cultural factors. Many problems faced by the elderly may be intrinsically related to how they see themselves and are perceived by others. It is therefore essential to affirm and share the positive aspects of being old and the ageing process, ensuring care and protection by the family and society to this social group.

  5. Why is toilet training occurring at older ages? A study of factors associated with later training.

    PubMed

    Blum, Nathan J; Taubman, Bruce; Nemeth, Nicole

    2004-07-01

    Recent studies suggest that children are completing toilet training much later than the preceding generation. Our objective was to identify factors associated with later toilet training. Children between 17 and 19 months of age (n=406) were enrolled in the study. At enrollment, parents completed the Parenting Stress Index and the Receptive-Expressive Emergent Language Scale. Follow-up parent interviews were conducted every 2 to 3 months until children completed daytime toilet training. Information obtained at follow-up interviews included steps parents were taking to toilet train their child, child toilet training behaviors, presence and frequency of constipation, birth of a sibling, and child care arrangements. In a stepwise linear regression model predicting age at completion of toilet training, 3 factors were consistently associated with later training: initiation of toilet training at an older age, presence of stool toileting refusal, and presence of frequent constipation. Models including these variables explained 25% to 39% of the variance in age at completion of toilet training. In conclusion, a later age at initiation of toilet training, stool toileting refusal, and constipation may explain some of the trend toward completion of toilet training at later ages.

  6. An age-adjusted seroprevalence study of Toxoplasma antibody in a Malaysian ophthalmology unit.

    PubMed

    Singh, Sujaya; Khang, Tsung Fei; Andiappan, Hemah; Nissapatorn, Veeranoot; Subrayan, Visvaraja

    2012-05-01

    Toxoplasma gondii is a public health risk in developing countries, especially those located in the tropics. Widespread infection may inflict a substantial burden on state resources, as patients can develop severe neurological defects and ocular diseases that result in lifelong loss of economic independence. We tested sera for IgG antibody from 493 eye patients in Malaysia. Overall age-adjusted seroprevalence was estimated to be 25% (95% CI: [21%, 29%]). We found approximately equal age-adjusted seroprevalence in Chinese (31%; 95% CI: [25%, 38%]) and Malays (29%; 95% CI: [21%, 36%]), followed by Indians (19%; 95% CI: [13%, 25%]). A logistic regression of the odds for T. gondii seroprevalence against age, gender, ethnicity and the occurrence of six types of ocular diseases showed that only age and ethnicity were significant predictors. The odds for T. gondii seroprevalence were 2.7 (95% CI for OR: [1.9, 4.0]) times higher for a patient twice as old as the other, with ethnicity held constant. In Malays, we estimated the odds for T. gondii seroprevalence to be 2.9 (95% CI for OR: [1.8, 4.5]) times higher compared to non-Malays, with age held constant. Previous studies of T. gondii seroprevalence in Malaysia did not explicitly adjust for age, rendering comparisons difficult. Our study highlights the need to adopt a more rigorous epidemiological approach in monitoring T. gondii seroprevalence in Malaysia.

  7. 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.

  8. 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…

  9. 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…

  10. 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...

  11. 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...

  12. 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…

  13. 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…

  14. 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…

  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. 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

  17. Body Mass Index at Age 20 and Subsequent Childbearing: The Adventist Health Study-2

    PubMed Central

    Knutsen, Synnøve F.; Oda, Keiji; Fraser, Gary E.

    2013-01-01

    Abstract Background Some epidemiological, clinical, and laboratory studies suggest that underweight and obesity impact fertility. Methods This is cross-sectional study of 33,159 North American Adventist women, who were nulliparous at age 20 years and who, as a group, have a healthy lifestyle. Logistic regression analysis was used to assess how body mass index (BMI, kg/m2) at age 20 was related to never becoming pregnant, never giving birth to a living child, or not giving birth to a second or third child. Results A total of 4954 (15%) of the women reported never becoming pregnant (nulligravidity) and 7461 (23%) women remained nulliparous. Underweight (BMI<18.5 kg/m2) at age 20 was associated with approximately 13% increased risk of nulligravidity or nulliparity. Women with BMI≥32.5 kg/m2 when aged 20 had 2.5 (95% CI: 2.0, 3.1) times increased odds of nulliparity compared to women with BMI 20–24.9 kg/m2. Increased risk was found for all groups of overweight women (BMI≥25 kg/m2). However, if the women gave birth to one live child after age 20, BMI≥32.5 kg/m2 at age 20 had less impact (OR 1.6 [95% CI: 1.2, 2.2]) on the likelihood of not delivering a second child. In women who delivered two living children, obesity at age 20 had no bearing on the odds of having a third child. Conclusions Obesity and, to a lesser extent, underweight at age 20 increases the nulliparity rate. The results underscore the importance of a healthy weight in young women. PMID:23611121

  18. Infant motor development and cognitive performance in early old age: the Helsinki Birth Cohort Study.

    PubMed

    Poranen-Clark, Taina; von Bonsdorff, Mikaela B; Lahti, Jari; Räikkönen, Katri; Osmond, Clive; Rantanen, Taina; Kajantie, Eero; Eriksson, Johan G

    2015-06-01

    Motor development and cognitive development in childhood have been found to be fundamentally interrelated, but less is known about the association extending over the life course. The aim of this study was to examine the association between early motor development and cognitive performance in early old age. From men and women belonging to the Helsinki Birth Cohort Study, who were born between 1934 and 1944 and resided in Finland in 1971, 1279 participated in cognitive performance tests (CogState®, version 3.0.5) between 2001 and 2006 at an average age of 64.2 years (SD 3.0). Of these, age at first walking extracted from child welfare clinic records was available for 398 participants. Longer reaction times in cognitive tasks measuring simple reaction time (SRT), choice reaction time (CRT), working memory (WM), divided attention (DA), and associated learning (AL) indicated poorer cognitive performance. Adjustment was made for sex, age at testing, father's occupational status and own highest attained education, and occupation in adulthood. Average age of learning to walk was 12.2 months (SD 2.1). After adjusting for covariates, earlier attainment of learning to walk was associated with shorter reaction times in cognitive performance tasks (SRT 10.32 % per month, 95 % CI 0.48-21.12, p = 0.039; CRT 14.17 % per month, 95 % CI 3.75-25.63, p = 0.007; WM 15.14 % per month, 95 % CI 4.95-26.32, p = 0.003). People who learned to walk earlier had better cognitive performance in early old age. The earlier attainment of motor skills may track over to early old age and possibly reflect greater cognitive reserve in older age. PMID:25929653

  19. Infant motor development and cognitive performance in early old age: the Helsinki Birth Cohort Study.

    PubMed

    Poranen-Clark, Taina; von Bonsdorff, Mikaela B; Lahti, Jari; Räikkönen, Katri; Osmond, Clive; Rantanen, Taina; Kajantie, Eero; Eriksson, Johan G

    2015-06-01

    Motor development and cognitive development in childhood have been found to be fundamentally interrelated, but less is known about the association extending over the life course. The aim of this study was to examine the association between early motor development and cognitive performance in early old age. From men and women belonging to the Helsinki Birth Cohort Study, who were born between 1934 and 1944 and resided in Finland in 1971, 1279 participated in cognitive performance tests (CogState®, version 3.0.5) between 2001 and 2006 at an average age of 64.2 years (SD 3.0). Of these, age at first walking extracted from child welfare clinic records was available for 398 participants. Longer reaction times in cognitive tasks measuring simple reaction time (SRT), choice reaction time (CRT), working memory (WM), divided attention (DA), and associated learning (AL) indicated poorer cognitive performance. Adjustment was made for sex, age at testing, father's occupational status and own highest attained education, and occupation in adulthood. Average age of learning to walk was 12.2 months (SD 2.1). After adjusting for covariates, earlier attainment of learning to walk was associated with shorter reaction times in cognitive performance tasks (SRT 10.32 % per month, 95 % CI 0.48-21.12, p = 0.039; CRT 14.17 % per month, 95 % CI 3.75-25.63, p = 0.007; WM 15.14 % per month, 95 % CI 4.95-26.32, p = 0.003). People who learned to walk earlier had better cognitive performance in early old age. The earlier attainment of motor skills may track over to early old age and possibly reflect greater cognitive reserve in older age.

  20. 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

  1. 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.

  2. 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.

  3. 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

  4. 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

  5. Age, period, and cohort effects on pulmonary function in a 24-year longitudinal study.

    PubMed

    Xu, X; Laird, N; Dockery, D W; Schouten, J P; Rijcken, B; Weiss, S T

    1995-03-15

    This paper proposes the use of two-factor models (age-period and age-cohort models) to estimate age, period, and cohort effects on pulmonary function by using the data collected in a 24-year longitudinal study in the Netherlands from 1965 to 1990. The analysis included 18,363 pulmonary function measurements on 6,148 subjects aged 20-54 years at the initial visit. The subjects were grouped into four birth cohorts (before 1923, 1923-1934, 1935-1946, and after 1946) and four survey periods (1965-1972, 1973-1978, 1979-1984, and 1985-1990). In the age-cohort model, the decrement in forced expiratory volume in 1 second (FEV1) associated with a yearly increase in age was 28.3 +/- 3.7 ml/year for a man 176 cm tall and 16.0 +/- 1.9 ml/year for a woman 163 cm tall. The estimated acceleration of decline with aging was significant for both men (beta = -0.212; standard error = 0.079 ml) and women (beta = -0.346; standard error = 0.058 ml). Compared with that of the cohort born before 1923, the average level of FEV1 was estimated to increase by 156, 277, and 379 ml, respectively, for the three younger cohorts in men (p = 0.01) and by 133, 213, and 328 ml for the three younger cohorts in women (p < 0.01). In the age-period model, the estimated linear age effect on FEV1 was 36.2 +/- 4.2 ml/year for a man and 30.5 +/- 2.3 ml/year for a woman. The age quadratic term was significant for women, but not for men. Average FEV1 was estimated to be increased by 141, 169, and 250 ml, respectively, for the periods 1973-1978, 1979-1984, and 1985-1990 in men and by 131, 138, and 219 ml in women. These period effects were significant for both men and women. In summary, this study applied the two-factor models to estimate cross-sectional and longitudinal effects of aging on FEV1 and demonstrated significant period and cohort effects, which could be attributed in part to changes in air pollutants, respiratory infections, vaccinations, types of cigarettes, diet, and lifestyles over time.

  6. Characteristics of first-time fathers of advanced age: a Norwegian population-based study

    PubMed Central

    2013-01-01

    Background The modern phenomenon of delayed parenthood applies not only to women but also to men, but less is known about what characterises men who are expecting their first child at an advanced age. This study investigates the sociodemographic characteristics, health behaviour, health problems, social relationships and timing of pregnancy in older first-time fathers. Methods A cross-sectional study was conducted of 14 832 men who were expecting their first child, based on data from the Norwegian Mother and Child Cohort Study (MoBa) carried out by the Norwegian Institute of Public Health. Data were collected in 2005–2008 by means of a questionnaire in gestational week 17–18 of their partner’s pregnancy, and from the Norwegian Medical Birth Register. The distribution of background variables was investigated across the age span of 25 years and above. Men of advanced age (35–39 years) and very advanced age (40 years or more) were compared with men aged 25–34 years by means of bivariate and multivariate logistic regression analyses. Results The following factors were found to be associated with having the first child at an advanced or very advanced age: being unmarried or non-cohabitant, negative health behaviour (overweight, obesity, smoking, frequent alcohol intake), physical and mental health problems (lower back pain, cardiovascular diseases, high blood pressure, sleeping problems, previous depressive symptoms), few social contacts and dissatisfaction with partner relationship. There were mixed associations for socioeconomic status: several proxy measures of high socioeconomic status (e.g. income >65 000 €, self-employment) were associated with having the first child at an advanced or very advanced age, as were several other proxy measures of low socioeconomic status (e.g. unemployment, low level of education, immigrant background).The odds of the child being conceived after in vitro fertilisation were threefold in men aged 34–39 and fourfold from 40

  7. Volumetric studies on the red nucleus of the rat at different ages.

    PubMed

    Boseila, A W; Hashem, S M; Badawy, Y H

    1975-01-01

    The postnatal development of the red nucleus in albino rat was quantitatively studied. Planimetric studies on stained paraffin sections of the midbrain showed that the red nucleus has a rounded contour with tapering ends and a broad centre. The volume of the red nucleus revealed an increase from birth, to reach its maximum at the age of 3 months, then declines until the age of 2 years. However, the size does not regain its newly born value. On the other hand, the number of cells remains constant during the entire life span of the animal.

  8. Barriers to Middle-Aged Women’s Mental Health: A Qualitative Study

    PubMed Central

    Sharifi, Khadijeh; Anoosheh, Monireh; Foroughan, Mahshid; Kazemnejad, Anushirvan

    2014-01-01

    Background: Middle-aged women encounter some barriers to their mental health, putting them at great risk for developing mental disorders. Objectives: The aim of this study was to explore barriers to middle-aged women’s mental health. Materials and Methods: This was a qualitative content analysis study conducted in 2013 in Kashan, Iran. A purposive, maximum variation sample of 23 middle-aged women was recruited to the study. Data were collected by conducting semi-structured individual interviews. We employed the conventional qualitative content analysis approach for data analysis. Results: Barriers to middle-aged women’s mental health fell into two main themes including ‘increased life concerns’ and ‘physical and psychological tensions’. The two sub-categories of the first theme included having mental concerns and increased burden of roles. The second main theme also consisted of two categories including perceived undesirable physical changes and perceived undesirable psychological changes. Conclusions: Experiences of middle-aged women showed that culturally appropriate interventions to alleviate the concerns of life, physical and mental stress is essential to preserve stability of mental health. PMID:25068059

  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. 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

  11. Morphometric study of histological changes in sublabial salivary glands due to aging process.

    PubMed Central

    De Wilde, P C; Baak, J P; van Houwelingen, J C; Kater, L; Slootweg, P J

    1986-01-01

    The sublabial salivary glands were studied by morphometric methods in 68 healthy volunteers to establish possible changes related to age in those tissue components that are affected in Sjögren's syndrome and connective tissue diseases (and which might stimulate Sjögren's syndrome). There was an increase in the amount of connective tissue and intralobular ducts with age and a corresponding decrease in acinar tissue. During the aging process changes in the intralobular ducts occurred: the outer and inner diameters of these ducts and the thickness of the epithelium decreased, but the ratio of the outer and inner diameters of the ducts remained constant. The amount of diffuse lymphoplasmacytic infiltrate and the vascularity of the tissue remains constant with age. In 15 of the subjects, however, discrete lymphocytic foci were seen and in six of these more than one focus/4 mm2 of salivary tissue was found, which has been described as suggestive of Sjögren's syndrome. The volume percentage of lymphocytic foci is constant during the aging process. The histological features commonly used to diagnose Sjögren's syndrome may occur in normal people, and false positive diagnoses will occur if these criteria are rigidly adhered to. Morphometry may provide more reliable criteria for distinguishing changes induced by inflammation and related to age which occur in salivary tissue. Images PMID:3700674

  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. 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

  14. 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

  15. The temperature dependence of atomic incorporation characteristics in growing GaInNAs films

    SciTech Connect

    Li, Jingling; Gao, Fangliang; Wen, Lei; Zhou, Shizhong; Zhang, Shuguang E-mail: msgli@scut.edu.cn; Li, Guoqiang E-mail: msgli@scut.edu.cn

    2015-02-07

    We have systematically studied the temperature dependence of incorporation characteristics of nitrogen (N) and indium (In) in growing GaInNAs films. With the implementation of Monte-Carlo simulation, the low N adsorption energy (−0.10 eV) is demonstrated. To understand the atomic incorporation mechanism, temperature dependence of interactions between Group-III and V elements are subsequently discussed. We find that the In incorporation behaviors rather than that of N are more sensitive to the T{sub g}, which can be experimentally verified by exploring the compositional modulation and structural changes of the GaInNAs films by means of high-resolution X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope, and secondary ion mass spectroscopy.

  16. Age-dependent changes in cat masseter nerve: an electrophysiological and morphological study.

    PubMed

    Chase, M H; Engelhardt, J K; Adinolfi, A M; Chirwa, S S

    1992-07-24

    The present study was undertaken to determine the manner in which aging affects the function and structure of the masseter nerve in old cats. Electrophysiological data demonstrated a significant decrease in the conduction velocity of the action potential in old cats compared with that observed in adult cats. Light microscopic analyses revealed an age-dependent decrease in axon diameter. Electron microscopic observations of the masseter nerve in the aged cats revealed a disruption of the myelin sheaths and a pronounced increase in collagen fibers in the endoneurium and perineurium. These morphological changes are discussed and then related to the decrease in conduction velocity which was observed in the electrophysiological portion of this study. PMID:1521161

  17. Effects of insertion of strain-engineering Ga(In)NAs layers on optical properties of InAs/GaAs quantum dots for high-efficiency solar cells

    NASA Astrophysics Data System (ADS)

    Pavelescu, Emil-Mihai; Polojärvi, Ville; Schramm, Andreas; Tukiainen, Antti; Aho, Arto; Zhang, Wenxin; Puustinen, Janne; Salmi, Joel; Guina, Mircea

    2016-02-01

    We report study on stacked InAs/GaNAs quantum dots heterostructures with dilute nitride GaInNAs strain mediating layers embedded in GaAs p-i-n solar cell structure. The insertion of GaInNAs strain mediating layers in the vicinity of the strain compensated InAs/GaNAs quantum dots heterostructures enhances their surface density, improves and significantly red shifts their light emission. Embedding a stack of the strain-mediated InAs/GaInNAs/GaNAs quantum dots in the i region of a GaAs p-i-n solar cell leads also to a red shift of the absorption edge of the solar cells and improves the solar cell photogenerated currents at longer wavelengths beyond 1200 nm.

  18. 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

  19. A correlation study of telomere length in peripheral blood leukocytes and kidney function with age.

    PubMed

    Zhang, Wei-Guang; Wang, Yong; Hou, Kai; Jia, Lin-Pei; Ma, Jie; Zhao, De-Long; Zhu, Shu-Ying; Bai, Xiao-Juan; Cai, Guang-Yan; Wang, Yan-Ping; Sun, Xue-Feng; Chen, Xiang-Mei

    2015-06-01

    The current study aimed to investigate the association between telomere length in peripheral blood leukocytes and kidney function in various age groups of a healthy population. A total of 139 healthy individuals were divided into five groups according to their age: 35‑44, 45‑54, 55‑64, 65‑74 and >75 years old. Peripheral blood leukocytes were obtained and the telomere restriction fragment (TRF) length was assayed using a digoxigenin‑labeled hybridization probe in Southern blot assays. Laboratory assays of kidney function were also performed. A correlation was observed between TRF length and age (r=‑0.314, P<0.001), with the telomere length of the individuals >75 years group being significantly shorter than the telomere length of the 35‑44, 45‑54 and 55‑64 years age groups (P<0.05). By contrast, the TRF length for males versus females did not differ for any of the age groups, while a correlation was observed between TRF length and serum levels of cystatin C (r=‑0.195, P<0.05). There was also a correlation between TRF length and glomerular filtration rate (r=‑0.184, P<0.05). The current study demonstrated that in this cohort, leukocyte telomere length reduced with age and was correlated with serum levels of cystatin C and glomerular filtration rate. Therefore, TRF length is associated with kidney function and may serve as a marker of aging.

  20. 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…

  1. Comparative study of age estimation using dentinal translucency by digital and conventional methods

    PubMed Central

    Bommannavar, Sushma; Kulkarni, Meena

    2015-01-01

    Introduction: Estimating age using the dentition plays a significant role in identification of the individual in forensic cases. Teeth are one of the most durable and strongest structures in the human body. The morphology and arrangement of teeth vary from person-to-person and is unique to an individual as are the fingerprints. Therefore, the use of dentition is the method of choice in the identification of the unknown. Root dentin translucency is considered to be one of the best parameters for dental age estimation. Traditionally, root dentin translucency was measured using calipers. Recently, the use of custom built software programs have been proposed for the same. Objectives: The present study describes a method to measure root dentin translucency on sectioned teeth using a custom built software program Adobe Photoshop 7.0 version (Adobe system Inc, Mountain View California). Materials and Methods: A total of 50 single rooted teeth were sectioned longitudinally to derive a 0.25 mm uniform thickness and the root dentin translucency was measured using digital and caliper methods and compared. The Gustafson's morphohistologic approach is used in this study. Results: Correlation coefficients of translucency measurements to age were statistically significant for both the methods (P < 0.125) and linear regression equations derived from both methods revealed better ability of the digital method to assess age. Conclusion: The custom built software program used in the present study is commercially available and widely used image editing software. Furthermore, this method is easy to use and less time consuming. The measurements obtained using this method are more precise and thus help in more accurate age estimation. Considering these benefits, the present study recommends the use of digital method to assess translucency for age estimation. PMID:25709325

  2. Lateralization patterns of covert but not overt movements change with age: An EEG neurofeedback study.

    PubMed

    Zich, Catharina; Debener, Stefan; De Vos, Maarten; Frerichs, Stella; Maurer, Stefanie; Kranczioch, Cornelia

    2015-08-01

    The mental practice of movements has been suggested as a promising add-on therapy to facilitate motor recovery after stroke. In the case of mentally practised movements, electroencephalogram (EEG) can be utilized to provide feedback about an otherwise covert act. The main target group for such an intervention are elderly patients, though research so far is largely focused on young populations (<30 years). The present study therefore aimed to examine the influence of age on the neural correlates of covert movements (CMs) in a real-time EEG neurofeedback framework. CM-induced event-related desynchronization (ERD) was studied in young (mean age: 23.6 years) and elderly (mean age: 62.7 years) healthy adults. Participants performed covert and overt hand movements. CMs were based on kinesthetic motor imagery (MI) or quasi-movements (QM). Based on previous studies investigating QM in the mu frequency range (8-13Hz) QM were expected to result in more lateralized ERD% patterns and accordingly higher classification accuracies. Independent of CM strategy the elderly were characterized by a significantly reduced lateralization of ERD%, due to stronger ipsilateral ERD%, and in consequence, reduced classification accuracies. QM were generally perceived as more vivid, but no differences were evident between MI and QM in ERD% or classification accuracies. EEG feedback enhanced task-related activity independently of strategy and age. ERD% measures of overt and covert movements were strongly related in young adults, whereas in the elderly ERD% lateralization is dissociated. In summary, we did not find evidence in support of more pronounced ERD% lateralization patterns in QM. Our finding of a less lateralized activation pattern in the elderly is in accordance to previous research and with the idea that compensatory processes help to overcome neurodegenerative changes related to normal ageing. Importantly, it indicates that EEG neurofeedback studies should place more emphasis on the

  3. Subclinical Atherosclerotic Calcification and Cognitive Functioning in Middle-Aged Adults: The CARDIA Study

    PubMed Central

    Reis, Jared P.; Launer, Lenore J.; Terry, James G.; Loria, Catherine M.; Hazzouri, Adina Zeki Al; Sidney, Stephen; Yaffe, Kristine; Jacobs, David R.; Whitlow, Christopher T.; Zhu, Na; Carr, J. Jeffrey

    2013-01-01

    Objective Cardiovascular risk factors in middle-age are associated with cognitive impairment and dementia in older age. Less is known about the burden of calcified subclinical atherosclerosis and cognition, especially in midlife. We examined the association of coronary artery and abdominal aortic calcified plaque (CAC and AAC, respectively) with cognitive functioning in middle-aged adults. Methods This cross-sectional study included 2,510 black and white adults (age: 43–55 years) without heart disease or stroke who completed a year 25 follow-up exam (2010–11) as part of the Coronary Artery Risk Development in Young Adults Study. CAC and AAC were measured with non-contrast computed tomography. Cognition was assessed with the Digit Symbol Substitution Test (DSST) (psychomotor speed), Stroop Test (executive function), and Rey Auditory Verbal Learning Test (RAVLT) (verbal memory). Results A greater amount of CAC and AAC was associated with worse performance on each test of cognitive function after adjustment for age, sex, race, education, and study center. Associations were attenuated, but remained significant for the DSST and RAVLT following additional adjustment for vascular risk factors, including adiposity, smoking, alcohol use, dyslipidemia, hypertension, and diabetes. Compared to participants without CAC or AAC, those with both CAC and AAC, but not CAC or AAC alone was associated with lower DSST scores (p<0.05). Conclusions In this community-based sample, greater subclinical atherosclerotic calcification was associated with worse psychomotor speed and memory in midlife. These findings underscore the importance of a life course approach to the study of cognitive impairment with aging. PMID:24125414

  4. Genetic Complexity of Episodic Memory: A Twin Approach to Studies of Aging

    PubMed Central

    Kremen, William S.; Spoon, Kelly M.; Jacobson, Kristen C.; Vasilopoulos, Terrie; McCaffery, Jeanne M.; Panizzon, Matthew S.; Franz, Carol E.; Vuoksimaa, Eero; Xian, Hong; Rana, Brinda K.; Toomey, Rosemary; McKenzie, Ruth; Lyons, Michael J.

    2016-01-01

    Episodic memory change is a central issue in cognitive aging, and understanding that process will require elucidation of its genetic underpinnings. A key limiting factor in genetically informed research on memory has been lack of attention to genetic and phenotypic complexity, as if “memory is memory” and all well-validated assessments are essentially equivalent. Here we applied multivariate twin models to data from late-middle-aged participants in the Vietnam Era Twin Study of Aging to examine the genetic architecture of 6 measures from 3 standard neuropsychological tests: the California Verbal Learning Test-2, and Wechsler Memory Scale-III Logical Memory (LM) and Visual Reproductions (VR). An advantage of the twin method is that it can estimate the extent to which latent genetic influences are shared or independent across different measures before knowing which specific genes are involved. The best-fitting model was a higher order common pathways model with a heritable higher order general episodic memory factor and three test-specific subfactors. More importantly, substantial genetic variance was accounted for by genetic influences that were specific to the latent LM and VR subfactors (28% and 30%, respectively) and independent of the general factor. Such unique genetic influences could partially account for replication failures. Moreover, if different genes influence different memory phenotypes, they could well have different age-related trajectories. This approach represents an important step toward providing critical information for all types of genetically informative studies of aging and memory. PMID:24956007

  5. Delivery by caesarean section and risk of obesity in preschool age children: a prospective cohort study

    PubMed Central

    Huh, Susanna Y; Rifas-Shiman, Sheryl L; Zera, Chloe A; Edwards, Janet W Rich; Oken, Emily; Weiss, Scott T; Gillman, Matthew W

    2013-01-01

    Objective To examine whether delivery by caesarean section is a risk factor for childhood obesity. Design Prospective pre-birth cohort study (Project Viva). Setting Eight outpatient multi-specialty practices based in the Boston, Massachusetts area. Participants We recruited women during early pregnancy between 1999 and 2002, and followed their children after birth. We included 1255 children with body composition measured at 3 years of age. Main outcome measures Body mass index (BMI) z-score, obesity (BMI for age and sex ≥ 95th percentile), and sum of triceps + subscapular skinfold thicknesses, at 3 years of age. Results 284 children (22.6 percent) were delivered by caesarean section. At age 3, 15.7% of children delivered by caesarean section were obese, compared with 7.5% of children born vaginally. In multivariable logistic and linear regression models adjusting for maternal pre-pregnancy BMI, birth weight, and other covariates, birth by caesarean section was associated with a higher odds of obesity at age 3 (OR 2.10, 95%CI 1.36 to 3.23), higher mean BMI z-score (0.20 units, 95% CI 0.07 to 0.33), and higher sum of triceps + subscapular skinfold thicknesses (0.94 mm, 95% CI 0.36 to 1.51). Conclusions Infants delivered by caesarean section may be at increased risk of childhood obesity. Further studies are needed to confirm our findings and to explore mechanisms underlying this association. PMID:22623615

  6. 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.

  7. 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.

  8. 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. PMID:2523851

  9. Age-Related Effects of Study Time Allocation on Memory Performance in a Verbal and a Spatial Task

    ERIC Educational Resources Information Center

    Krueger, Lacy E.

    2012-01-01

    Past studies have suggested that study time allocation partially mediates age relations on memory performance in a verbal task. To identify whether this applied to a different material modality, participants ages 20-87 completed a spatial task in addition to a traditional verbal task. In both the verbal and the spatial task, increased age was…

  10. UAS in the NAS Flight Test Series 3 Overview

    NASA Technical Reports Server (NTRS)

    Murphy, James R.

    2015-01-01

    The UAS Integration in the NAS Project is conducting a series of flight tests to acheive the following objectives: 1.) Validate results previously collected during project simulations with live data 2.) Evaluate TCAS IISS interoperability 3.) Test fully integrated system in a relevant live test environment 4.) Inform final DAA and C2 MOPS 5.) Reduce risk for Flight Test Series 4.

  11. Unstructured Adaptive (UA) NAS Parallel Benchmark. Version 1.0

    NASA Technical Reports Server (NTRS)

    Feng, Huiyu; VanderWijngaart, Rob; Biswas, Rupak; Mavriplis, Catherine

    2004-01-01

    We present a complete specification of a new benchmark for measuring the performance of modern computer systems when solving scientific problems featuring irregular, dynamic memory accesses. It complements the existing NAS Parallel Benchmark suite. The benchmark involves the solution of a stylized heat transfer problem in a cubic domain, discretized on an adaptively refined, unstructured mesh.

  12. Mortality in Children Aged 0-9 Years: A Nationwide Cohort Study from Three Nordic Countries

    PubMed Central

    Yu, Yongfu; Qin, Guoyou; Cnattingius, Sven; Gissler, Mika; Olsen, Jørn; Zhao, Naiqing; Li, Jiong

    2016-01-01

    Background Mortality in children under five years has been widely studied, whereas mortality at 5–9 years has received little attention. Using unique data from national registers in three Nordic countries, we aimed to characterize mortality directionality in children aged 0 to 9 years. Methods and Findings The cohort study included all children born in Denmark from 1973 to 2008 (n = 2,433,758), Sweden from 1973 to 2006 (n = 3,400,212), and a random sample of 89.3% of children born in Finland from 1987 to 2007 (n = 1,272,083). Children were followed from 0 to 9 years, and cumulative mortality and mortality rates were compared by age, gender, cause of death, and calendar periods. Among the 7,105,962 children, there were 48,299 deaths during study period. From 1981–1985 to 2001–2005, all-cause mortality rates were reduced by between 34% and 62% at different ages. Overall mortality rate ratio between boys and girls decreased from 1.25 to 1.21 with the most prominent reduction in children aged 5–9 years (from 1.59 to 1.19). Neoplasms, diseases of the nervous system and transport accidents were the most frequent cause of death after the first year of life. These three leading causes of death declined by 42% (from 6.2 to 3.6 per 100,000 person years), 43% (from 3.7 to 2.1) and 62% (from 3.9 to 1.5) in boys, and 25% (from 4.1 to 3.1 per 100000 person years), 42% (from 3.4 to 1.9) and 63% (from 3.0 to 1.1) in girls, respectively. Mortality from neoplasms was the highest in each age except infants when comparing cause-specific mortality, and half of deaths from diseases of the nervous system occurred in infancy. Mortality rate due to transport accidents increased with age and was highest in boys aged 5–9 years. Conclusions Mortality rate in children aged 0–9 years has been decreasing with diminished difference between genders over the past decades. Our results suggest the importance of further research on mortality by causes of neoplasms, and causes of transport

  13. Professional careers, work constraints, and age-related selection: a study on 21,000 wage-earners of four age cohorts in 1990 and 1995.

    PubMed

    Molinié, A F

    1999-01-01

    The French work force is aging, like that of many other European countries. Projections underscore that over the next 20 years there will be a dramatic increase in the working population over 45 years. Working conditions in France tend to increase the difficulties for aging workers: the work schedules are less stable, the constraints of work rhythms become greater, etc. We are interested in the age-related selection mechanisms that may stem from the confrontation of two evolutions, aging of operators and transformations in the work situations (Molinié & Volkoff, 1994). Most studies on this subject generally rely on observation of populations in different age groups at a given date. But the selection processes can only really be detected in a dynamic framework, by incorporating observations on the assignment of wage-earners of different ages into a study of professional careers. We have been able to formulate a quantitative approach of selection mechanisms, thanks to the Health, Work, and Ageing Survey ("ESTEV"), which was based on a random sample of 21,000 wage-earners followed-up by work physicians (400 in 1990, 1000 in 1995). Subjects, male and female, belonged to age groups of 5-year intervals, from 1938 to 1953. Each age cohort included about 3000 subjects for men, and about 2000 for women (Derriennic, Touranchet, & Volkoff, 1996). They were first interviewed in 1990, and again in 199 (percentage of subjects seen both times: 87%). The present study relies on 22 questions aimed at identifying the constraints or hardships that the surveyed workers have encountered in the course of their working life. In each case, the worker was asked whether he or she was presently exposed, was not now but had been exposed, or had never been exposed to the constraint.

  14. 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. PMID:27544533

  15. 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

  16. 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).…

  17. 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…

  18. 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…

  19. 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…

  20. Democratic Citizenship Education in the Information Age: A Comparative Study of South Korea and Australia

    ERIC Educational Resources Information Center

    Roh, Young-Ran

    2004-01-01

    Democratic citizenship education in the information age must concern itself with the goal of nurturing future generations with the capacity to make appropriate use of the changes driven by the advances of ICTs so as to activate political and social democracy. Using Australia and South Korea as case studies, this paper discusses the role that…

  1. Motivation and Strategies for Learning in Traditional-Aged College Students: An Exploratory Study

    ERIC Educational Resources Information Center

    Santarosa, Stephanie R.

    2011-01-01

    This exploratory study uses the 15 scales of the Motivated Strategies for Learning Questionnaire (MSLQ) to examine how traditional-aged college students in their first year of college compare with those who have persisted to their second year. In addition, the relationship of students' motivation levels and use of learning strategies with student…

  2. 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...

  3. 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…

  4. 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…

  5. 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…

  6. 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…

  7. Toward a Social Phenomenology of Aging: Studying the Self Process in Biographical Work.

    ERIC Educational Resources Information Center

    Starr, Jerold M.

    1982-01-01

    Suggests that the established life history approach to the study of aging has been reformulated to include the macrostructural and cultural context. Demonstrates the utility of some core concepts in social phenomenology and ethnomethodology, particularly Schutz's concept of biographical work, for developing this new conception of the self.…

  8. 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...

  9. 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…

  10. Addressing the Myths and Realities of Age in a Russian Theatre Study.

    ERIC Educational Resources Information Center

    Mikhailova, Anna

    1994-01-01

    Reports on an extensive study conducted with 10- to 12-year-old children in 3 Moscow schools to determine their aesthetic perceptions and comprehension of layers of metaphoric meanings in the Leningrad Theatre for Young Spectators' production of "Bambi." Shows that metaphoric comprehension decreases within this age group, countering the myth that…

  11. 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…

  12. 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,…

  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. 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…

  15. 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…

  16. 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…

  17. 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.

  18. 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.

  19. Brain aging, memory impairment and oxidative stress: a study in Drosophila melanogaster.

    PubMed

    Haddadi, Mohammad; Jahromi, Samaneh Reiszadeh; Sagar, B K Chandrasekhar; Patil, Rajashekhar K; Shivanandappa, T; Ramesh, S R

    2014-02-01

    Memory impairment during aging is believed to be a consequence of decline in neuronal function and increase in neurodegeneration. Accumulation of oxidative damage and reduction of antioxidant defense system play a key role in organismal aging and functional senescence. In our study, we examined the age-related memory impairment (AMI) in relation to oxidative stress using Drosophila model. We observed a decline in cognitive function in old flies with respect to both short-lived and consolidated forms of olfactory memory. Light and electron microscopy of mushroom bodies revealed a reduction in the number of synapses and discernible architectural defects in mitochondria. An increase in neuronal apoptosis in Kenyon cells was also evident in aged flies. Biochemical investigations revealed a comparable age-associated decrease in the activity of antioxidant enzymes such as catalase and superoxide dismutase as well as the GSH level, accompanied by an increase in the level of lipid peroxidation and generation of reactive oxygen species in the brain. There was no significant difference in the activity level of AChE and BChE enzymes between different age groups while immunohistochemical studies showed a significant decrease in the level of ChAT in 50-day-old flies. RNAi-mediated silencing of cat and sod1 genes caused severe memory impairment in 15-day-old flies, whereas, over-expression of cat gene could partially rescue the memory loss in the old flies. We demonstrated that a Drosophila long-lived strain, possessing enhanced activity of antioxidant enzymes and higher rate of resistance to oxidative stress, shows lower extent of AMI compared to normal lifespan strain. Present study provides evidence for involvement of oxidative stress in AMI in Drosophila. PMID:24183945

  20. 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

  1. 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.

  2. 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.

  3. Collateral sprouting of central noradrenergic neurons during aging: histochemical and neurochemical studies in intraocular triple transplants.

    PubMed

    Srivastava, N; Granholm, A C; Gerhardt, G A

    1997-06-01

    The sprouting capacity of aged noradrenergic neurons of the brain-stem nucleus locus coeruleus (LC) was examined using intraocular transplants of fetal tissues. Fetal hippocampal tissue (E18) and LC tissue (E15) were transplanted together as a double transplant into the anterior chamber of the eye of young adult Fischer 344 rats. The double transplants were allowed to mature for 14-18 months, after which an additional fetal hippocampal transplant was placed next to the LC graft. The triple transplants were monitored for overall growth and vascularization for an additional 2-6 months. Immunohistochemical examinations showed that both young (2-6 months old) and aged (16-24 months old) hippocampal cografts contained a plexus of thin varicose tyrosine hydroxylase (TH)-immunoreactive fibers extending throughout the grafted hippocampal tissues. However, the aged hippocampal grafts contained a denser uniform plexus of TH-positive fibers compared to the young transplants. Immunohistochemistry with synapsin antibodies demonstrated that both the young and the aged hippocampal transplants contained much higher densities of synaptic elements than the LC grafts. In vivo electrochemical measurements of potassium-evoked overflow of norepinephrine (NE) in the grafts showed that similar amounts of NE overflow were detected in both the young and the aged hippocampal grafts. HPLC-EC measurements of NE levels in the grafts revealed that there were similar amounts of NE in the young and the aged grafts, and the grafts did not contain serotonin or dopamine. In summary, the findings of the present study show that aged LC neurons are capable of undergoing collateral sprouting producing a functional NE neuronal system when introduced to an appropriate young target. PMID:9217088

  4. Treadmill Exercise Attenuates Retinal Oxidative Stress in Naturally-Aged Mice: An Immunohistochemical Study.

    PubMed

    Kim, Chan-Sik; Park, Sok; Chun, Yoonseok; Song, Wook; Kim, Hee-Jae; Kim, Junghyun

    2015-01-01

    In the retina, a number of degenerative diseases, including glaucoma, diabetic retinopathy, and age-related macular degeneration, may occur as a result of aging. Oxidative damage is believed to contribute to the pathogenesis of aging as well as to age-related retinal disease. Although physiological exercise has been shown to reduce oxidative stress in rats and mice, it is not known whether it has a similar effect in retinal tissues. The aim of this study was to evaluate retinal oxidative stress in naturally-aged mice. In addition, we evaluated the effects of aerobic training on retinal oxidative stress by immunohistochemically evaluating oxidative stress markers. A group of twelve-week-old male mice were not exercised (young control). Two groups of twenty-two-month-old male mice were created: an old control group and a treadmill exercise group. The old control group mice were not exercised. The treadmill exercise group mice ran on a treadmill (5 to 12 m/min, 30 to 60 min/day, 3 days/week for 12 weeks). The retinal thickness and number of cells in the ganglion cell layer of the naturally-aged mice were reduced compared to those in the young control mice. However, treadmill exercise reversed these morphological changes in the retinas. We evaluated retinal expression of carboxymethyllysine (CML), 8-hydroxy-2'-deoxyguanosine (8-OHdG) and nitrotyrosine. The retinas from the aged mice showed increased CML, 8-OHdG, and nitrotyrosine immunostaining intensities compared to young control mice. The exercise group exhibited significantly lower CML levels and nitro-oxidative stress than the old control group. These results suggest that regular exercise can reduce retinal oxidative stress and that physiological exercise may be distinctly advantageous in reducing retinal oxidative stress. PMID:26404251

  5. 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. PMID:25354028

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

    PubMed

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

    2010-10-01

    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.

  7. F/NAS/ Pressure Temperature Retrieval Techniques

    NASA Technical Reports Server (NTRS)

    Poularikas, Alexander

    1995-01-01

    The purpose of this investigation is to study methods and ways for rapid inversion programs involving the correlated k-method, and to modify the existing programs so that the rapid analysis of data can be accomplished. This short paper presents the background regarding the research as well as accomplishments made during the contract period.

  8. In situ activity recovery of aging biofilm in biological aerated filter: Surfactants treatment and mechanisms study.

    PubMed

    Yu, Qisheng; Huang, Hui; Ren, Hongqiang; Ding, Lili; Geng, Jinju

    2016-11-01

    In situ activity recovery of aging biofilm in the biological aerated filter (BAF) is an important but underappreciated problem. Lab-scaled BAFs were established in this study and three kinds of surfactants containing sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate (SDBS) and rhamnolipid were employed. Multiple indicators including effluent qualities, dissolved organic matters, biofilm physiology and morphology characteristics were investigated to explore the mechanisms. Results showed that removal rates of effluent COD in test groups significantly recovered to the level before aging. Compared with the control, effluent in SDBS and rhamnolipid-treated groups obtained more protein-like and humic-like substances, respectively. Furthermore, great live cell ratio, smooth surface and low adhesion force of biofilm were observed after rhamnolipid treatment, which was in consistent with good effluent qualities in the same group. This is the first report of applying rhamnolipid for in situ activity recovery of aging biofilm in bioreactors. PMID:27513646

  9. Lifetime studies of security inks using a novel gonio-spectrometer with in situ aging capability

    NASA Astrophysics Data System (ADS)

    Emerich, Markus; Rosenberg, Erwin; Deinhammer, Harald; Paleczek, Susanne; Fajmann, Peter; Schwarzbach, Daniel

    2004-06-01

    The state of the art in manufacturing security documents includes the usage of a multitude of inks and pigments. The chemical and physical stability of these materials is a crucial point for their application in long lasting security products such as banknotes. For our studies regarding the bleaching characteristics of pigments and inks we have developed a highly integrated double beam gonio-spectrometer with in-situ ageing capability. The new spectrometer is equipped with a stabilized solar simulator lamp featuring a dosimeter, which is an advanced alternative to the commonly used blue wool scale. Additionally the sample temperature can be stabilized during ageing tests by a thermostatted sample holder. The instrument is capable of performing reflection measurements using monochromatic and polychromatic excitation and further allows fluorescence, phosphorescence and polarization measurements with high resolution over a wide wavelength range. We will present first results of defined ageing tests on a variety of security pigments and the setup of the newly developed spectrometer.

  10. A registry study of the association of patient's residence and age with colorectal cancer survival.

    PubMed

    Sankaranarayanan, Jayashri; Qiu, Fang; Watanabe-Galloway, Shinobu

    2014-04-01

    Because of limited literature from rural states of the United States like Nebraska, we evaluated the association of patient's age, Office of Management and Budget residence-county categories (rural-nonmetro, micropolitan-nonmetro, urban), and significant interactions between confounding-variables with colorectal cancer (CRC) survival. This retrospective 1998-2003 study of 6561 CRC patients from the Nebraska Cancer Registry showed median patient survival in colon and rectal cancer in urban, rural and micropolitan counties were 33, 36, and 46 months and 41, 47, 49 months, respectively. In Cox proportional-hazards analyses, after adjusting for significant demographics (age, race, marital status in colon cancer; age, insurance status in rectal cancer), cancer stage, surgery and radiation treatments; 1) no-chemotherapy urban colon cancer patients had significantly shorter survival (rural vs urban; adjusted hazard ratio, HR: 0.78 or urban vs rural HR: 1.28; micropolitan vs urban, HR: 0.78) and 2) no-surgery urban (vs rural, HR: 1.49); micropolitan (vs rural, HR: 2.01) rectal cancer patients had significantly shorter survival. Colon cancer (≥65 years) and rectal cancer (≥75 years) elderly each versus patients aged 19-64 years old had significantly shorter survival (all p < 0.01). The association of patients' age and treatment/residence-county interactions with CRC survival warrant decision-makers' attention.

  11. The potential role of stereolithography in the study of facial aging.

    PubMed

    Pessa, J E

    2001-02-01

    The potential role of high-resolution stereolithography for the study of facial aging was evaluated. Stereolithography has been used extensively in the engineering sciences to create model replicas prior to full production. More recently, stereolithography has found a role in the preoperative planning of complex dentofacial anomalies. Previous work has suggested that continued differential growth of the maxilla may occur throughout life. To further evaluate this finding, computed tomography scans were collected from younger (mean, 20.2 years) and older (mean, 58.8 years) individuals (N = 20). Both men and women were included. An exact replica of the facial skeleton was made for each subject by the process of laser polymerization. The angles of the maxillary wall and piriform aperture, defined by specific points, were measured relative to sella-nasion. Height, width, and depth changes were also evaluated. Findings show that angular changes occurred with age. The mean angle of the maxilla relative to sella-nasion decreased from 69 degrees to 56.8 degrees with age (P =.015). The mean angle of the piriform likewise decreased from 65.1 degrees to 55.7 degrees (P =.019). This angular change with age suggests that differential growth may continue throughout life. This work highlights the potential role of 3-dimensional modeling for future research in the field of facial aging. Curve and contour analysis are 2 additional areas in which stereolithography may yield valuable insights into the mechanisms of facial growth.

  12. Proactive Aging: A Longitudinal Study of Stress, Resources, Agency and Well-being in Late Life

    PubMed Central

    Kahana, Eva; Kelley-Moore, Jessica; Kahana, Boaz

    2012-01-01

    Objectives Using the Proactivity Model of Successful Aging, we examined how internal and external resources contribute to the maintenance of psychological well-being and social activities among older adults who experience normative stressors of aging. Outcome variables in this study are collectively referred to as quality of life (QOL). We also examined the mediating role of proactive adaptations between internal and external resources and QOL indicators. Method Based on five annual interviews of a sample of 1,000 community dwelling older adults in Florida (effective N = 561), we tested the lagged effects of stressors on two indicators of QOL, four years later. In the full longitudinal model, using structural equations, we estimated the direct effects of internal and external resources on QOL, along with indirect effects through proactive adaptations. Results Stressors negatively influenced QOL four years later. Internal and external resources led to better QOL four years later, both directly and indirectly through proactive adaptations of marshaling support and planning for the future. Conclusion These findings lend support to the Proactivity Model of Successful Aging by documenting the value of proactive adaptations (i.e., exercise, planning ahead and marshaling support) as proximate influences on QOL outcomes (i.e., depressive symptomatology and social activities). Findings suggest that older adults can maintain successful aging even in the face of health-related and social stressors by invoking accumulated resources to deal actively with the challenges of aging. PMID:22299813

  13. Improving Bone Microarchitecture in Aging with Diosgenin Treatment: A Study in Senescence-Accelerated OXYS Rats.

    PubMed

    Tikhonova, Maria A; Ting, Che-Hao; Kolosova, Nataliya G; Hsu, Chao-Yu; Chen, Jian-Horng; Huang, Chi-Wen; Tseng, Ging-Ting; Hung, Ching-Sui; Kao, Pan-Fu; Amstislavskaya, Tamara G; Ho, Ying-Jui

    2015-10-31

    Osteoporosis is a major disease associated with aging. We have previously demonstrated that diosgenin prevents osteoporosis in both menopause and D-galactose-induced aging rats. OXYS rats reveal an accelerated senescence and are used as a suitable model of osteoporosis. The aim of the present study was to analyze microarchitecture and morphological changes in femur of OXYS rats using morphological tests and microcomputed tomography scanning, and to evaluate the effects of oral administration of diosgenin at 10 and 50 mg/kg/day on femur in OXYS rats. The result showed that, compared with age-matched Wistar rats, the femur of OXYS rats revealed lower bone length, bone weight, bone volume, frame volume, frame density, void volume, porosity, external and internal diameters, cortical bone area, BV/TV, Tb.N, and Tb.Th, but higher Tb.Sp. Eight weeks of diosgenin treatment decreased porosity and Tb.Sp, but increased BV/TV, cortical bone area, Tb.N and bone mineral density, compared with OXYS rats treated with vehicle. These data reveal that microarchitecture and morphological changes in femur of OXYS rats showed osteoporotic aging features and suggest that diosgenin may have beneficial effects on aging-induced osteoporosis. PMID:26387656

  14. Artificial aging processes in modern papers: X-ray spectrometry studies

    NASA Astrophysics Data System (ADS)

    Manso, M.; Pessanha, S.; Carvalho, M. L.

    2006-08-01

    Artificial accelerated aging paper methods were used to study the cellulose alteration in paper, involving several mechanisms which may influence the paper elemental constitution. Different kinds of modern paper and papyrus were submitted to several weathering processes; intense ultraviolet and solar lights, humidity, high temperature, oxidization by NO 4I, and biodegradation by cellulosomes. In this work, energy dispersive X-ray fluorescence was used to quantify S, Cl, K, Ca, Mn, Fe, Cu, Zn, As, Sr, Ba and Pb and X-ray diffraction spectrometry was used to compare the phase differences in the original paper samples and after each aging treatment. Different elemental compositions were observed in modern papers and in papyrus which allows distinguishing them. With a ternary diagram based on elemental composition, we can perfectly identify each kind of paper sample. The obtained results concerning the used artificial aging processes in paper show that only the oxidization by NO 4I and biodegradation by cellulosomes affected the elemental content of paper, for S, Cl, K, Ca and Sr. These results are evidenced in the dendograms performed with the elemental concentrations for treated and untreated samples, respectively. Some differences were obtained in the diffractograms for aging process of some papers, which means that crystal phase changes occurred during the corresponding aging process.

  15. [Factors associated with age at first intercourse: a population-based study].

    PubMed

    Hugo, Tairana Dias de Oliveira; Maier, Vanessa Teixeira; Jansen, Karen; Rodrigues, Cristine Eliane Gomes; Cruzeiro, Ana Laura Sicca; Ores, Liliane da Costa; Pinheiro, Ricardo Tavares; Silva, Ricardo; Souza, Luciano Dias de Mattos

    2011-11-01

    First sexual intercourse is considered an important event in young people's lives and has occurred at an increasingly early age. The aim of this study was to identify factors associated with early age at first intercourse in individuals 18 to 24 years of age in Pelotas, Rio Grande do Sul State, Brazil. This was a population-based cross-sectional study in a representative sample of 1,621 young people from August 2007 to December 2008. Subjects answered a questionnaire on health behaviors, including items related to their sexual lives. Cox regression was used to assess the association between early age at sexual initiation. After multivariate analysis, variables that are directly related to early sexual initiation were: male gender, low socioeconomic status, low schooling, divorced parents, living with a partner, not practicing a religion, smoking, drug use in the previous three months, and non-use of condoms during last intercourse. Considering the current social context, the study highlights the need for adequate sexual orientation with a preventive approach.

  16. 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

  17. 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. PMID:22826292

  18. 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. PMID:27298487

  19. Aging and DNA damage in humans: a meta‐analysis study.

    PubMed

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

    2014-06-01

    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 metaanalysis 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

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

    PubMed

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

    2014-08-01

    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. PMID:24992972

  1. 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

  2. Longitudinal study exploring factors associated with neck/shoulder pain at 52 years of age

    PubMed Central

    Hesselman Borg, Johanna; Westerståhl, Maria; Lundell, Sara; Madison, Guy; Aasa, Ulrika

    2016-01-01

    Objectives To investigate the ability of work-related measurements, body composition, physical activity, and fitness levels to predict neck/shoulder pain (upper body pain, UBP) at the age of 52 years. Another aim was to investigate the cross-sectional relationships between UBP, work-related factors, and individual factors at the age of 52 years. Methods We followed a randomly selected cohort of 429 adolescents that was recruited in 1974 (baseline), when they were 16 years old. The participants completed physical fitness tests, questions about sociodemographic and lifestyle factors at 16, 34, and 52 years of age, and questions about work-related factors and pain in the follow-ups. Logistic regression analyses were used to examine the associations between UBP and the other variables. Results Univariate logistic regression analyses showed that high body mass index and the work-related factors, low control, and low social support at the age of 34 years were related to UBP at the age of 52 years. For social support, there was an interaction between men and women where the relationship between low social support and the experience of pain was more evident for women. Among women, body mass index and social support remained significantly related in the multivariate analyses. For men, social support remained significantly related. Cross-sectional relationships at the age of 52 differed from the longitudinal in the sense that measures of joint flexibility and work posture were also significantly associated with UBP. Conclusion The fact that the cross-sectional differed from the longitudinal relationships strengthens the importance of performing longitudinal studies when studying factors that might influence the initiation of pain. UBP preventative measures might need to include both lifestyle (such as dietary habits and physical activity to ensure that the individuals are not becoming overweight) and work-related factors such as social support. PMID:27307762

  3. An in vitro tissue model to study the effect of age on nucleus pulposus cells

    PubMed Central

    Hamilton, D.; Séguin, C.; Li, S.-Q.; Arana, C.; Pilliar, R.

    2007-01-01

    Differentiation between age (physiological) and disease-induced changes in the nucleus pulposus will facilitate our understanding of the mechanism(s) leading to the development of degenerative disc disease. The aim of this study was to develop an in vitro model that would allow the study of age-induced alterations of cell function in nucleus pulposus. Nucleus pulposus (NP) cells were isolated from intervertebral discs obtained from either calves (<9 months) or cows (>18 months). The cells were placed in culture and grown for 19 days. Although nucleus pulposus tissue was formed by the cells of the two different ages the more mature (older) cells formed less tissue as determined histologically by light microscopy. This was confirmed biochemically as the wet weight and proteoglycan content of the tissue formed by the older cells were significantly less than that of the younger tissue. The older cells accumulated less proteoglycans as determined by quantifying radioisotope incorporation. The older cells showed lower constitutive gene expression of collagen type II and aggrecan whereas collagen type I and link protein levels were similar to those of the younger cells. Metalloprotease (MMP) 13 gene and protein expression increased with age. There was no change in the levels of gene expression of MMP 2 and TIMP 1, 2, or 3 with age. Cells obtained from NP tissue harvested from younger or mature animals showed both genotypic and phenotypic differences in vitro that resulted in the inability of the older cells to reconstitute their extracellular matrix to the same extent as the younger cells. This suggests that this in vitro NP tissue model will be suitable to determine the mechanism(s) regulating age-induced changes. PMID:17710448

  4. F/NAS/Pressure Temperature Retrieval Techniques

    NASA Technical Reports Server (NTRS)

    Poularikas. Alexander

    1998-01-01

    The purpose of this investigation is to study methods and ways for rapid inversion programs involving the correlated k-method, and to modify the existing programs so that the rapid analysis of data can be accomplished. Extensive modifications of the software programs were introduced. These modifications were imposed on the radiative transfer models and inversion methods and resulted in incorporating some important atmospheric processes not previously considered. The software also was improved to handle several toxic gases, gases that were observed in Saturn's atmosphere, and to retrieve pressure-temperature profiles from infrared solar absorption spectra.

  5. Age-related changes in ac-impedance spectroscopy studies of normal human dentine: further investigations.

    PubMed

    Eldarrat, A H; High, A S; Kale, G M

    2010-01-01

    One of the age-related changes occurring in dentine structure is the formation of peritubular dentine on the inner walls of dentinal tubules leading to complete closure of tubules. Ac-impedance is safe, fast and non-invasive technique. In the last decade, the popularity of the technique has increased in dental research. Several investigators have used the technique to detect tooth cracks and caries. The results of in vitro studies showed that ac-impedance technique was more advanced for caries detection than visual and radiographic methods. However, other studies demonstrated that the accuracy of impedance measurements can be affected by many factors such as remineralization after tooth eruption. A study has been published on effect of age on impedance measurements by the authors for two age groups by employing ac-impedance spectroscopy. Therefore, the aim of this study was to demonstrate the importance of this technique by conducting further investigations on dentine samples of wider age groups. Dentine samples were prepared from extracted sound third molars of known patient age. The ac-impedance measurements were carried out over a wide range of frequency. After performing all electrical measurements, dentine samples were examined under SEM to correlate the electrical measurements with their structure. Impedance measurements showed that there were differences in impedance between young and old dentine. One-way ANOVA of the means of resistance and capacitance for all age groups (20, 25, 30, 40 and 50 years old dentine) revealed a significant difference (ANOVA, P < 0.0001) as a function of age. Applying Tukey's post hoc test, to the same data showed that this difference was due to the 50 years old dentine for resistance and was due to the 40 and 50 years old dentine for capacitance which were statistically different to all other groups. SEM investigation of dentine samples showed that young dentine is characterized by open dentinal tubules distributed all over the

  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. The Age-Related Eye Disease Study (AREDS): Design Implications AREDS Report No. 1

    PubMed Central

    2006-01-01

    The Age-Related Eye Disease Study (AREDS) was initially conceived as a long-term multicenter, prospective study of the clinical course of age-related macular degeneration (AMD) and age-related cataract. Data on progression rates and risk factors from the study will increase understanding of the clinical course of both conditions, generate hypotheses about etiology, and aid in the design of clinical trials of potential interventions. In addition to collecting natural history data, AREDS includes a clinical trial of high-dose vitamin and mineral supplements for AMD and a clinical trial of high-dose vitamin supplements for cataract. The clinical trials were initiated largely because of the widespread public use in the United States of commercially available pharmacologic doses of vitamins and minerals to treat these two eye conditions and the absence of definitive studies on the safety and efficacy of their use. Important design issues for the clinical trials include: defining cataract and AMD, estimating event rates, determining the type and dosage of vitamins and minerals to be tested for each condition, and identifying the parameters necessary for monitoring safety and efficacy. This paper describes the AREDS design, including the study rationale and operational structure, and the approach adopted to combine, for two diseases, clinical trials with a natural history study. PMID:10588299

  8. The NAS Perchlorate Review: Adverse Effects?

    SciTech Connect

    Johnston, Richard B.; Corley, Richard; Cowan, Linda; Utiger, Robert D.

    2005-11-01

    To the editor: Drs. Ginsberg and Rice argue that the reference dose for perchlorate of 0.0007 mg/kg per day recommended by the National Academies’ Committee to Assess the Health Implications of Perchlorate Ingestion is not adequately protective. As members of the committee, we disagree. Ginsberg and Rice base their conclusion on three points. The first involves the designation of the point of departure as a NOEL (no-observed-effect level) versus a LOAEL (lowest-observed-adverse- effect level). The committee chose as its point of departure a dose of perchlorate (0.007 mg/kg per day) that when given for 14 days to 7 normal subjects did not cause a significant decrease in the group mean thyroid iodide uptake (Greer et al. 2002). Accordingly, the committee considered it a NOEL. Ginsberg and Rice focus on the fact that only 7 subjects were given that dose, and they 1seem to say that attention should be paid only to the results in those subjects in whom there was a 1fall in thyroid iodide uptake, and that the results in those in whom there was no fall or an increase should be ignored. They consider the dose to be a LOAEL because of the fall in uptake in those few subjects. It is important to note that a statistically significant decrease of, for example, 5% or even 10%, would not be biologically important and, more important, would not be sustained. For example, in another study (Braverman et al. 2004), administration of 0.04 mg/kg per day to normal subjects for 6 months had no effect on thyroid iodide uptake when measured at 3 and 6 months, and no effect on serum thyroid hormone or thyrotropin concentrations measured monthly (inspection of Figure 5A in the paper by Greer et al. suggests that this dose would inhibit thyroid iodide uptake by about 25% if measured at 2 weeks). The second issue involves database uncertainty. In clinical studies, perchlorate has been administered prospectively to 68 normal subjects for 2 weeks to 6 months. In one study (Brabant et al. 1992

  9. 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.

  10. 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

  11. High Basal Metabolic Rate Is a Risk Factor for Mortality: The Baltimore Longitudinal Study of Aging

    PubMed Central

    Ruggiero, Carmelinda; Metter, E. Jeffrey; Melenovsky, Vojtech; Cherubini, Antonio; Najjar, Samer S.; Ble, Alessandro; Senin, Umberto; Longo, Dan L.; Ferrucci, Luigi

    2016-01-01

    Background Despite longstanding controversies from animal studies on the relationship between basal metabolic rate (BMR) and longevity, whether BMR is a risk factor for mortality has never been tested in humans. We evaluate the longitudinal changes in BMR and the relationship between BMR and mortality in the Baltimore Longitudinal Study of Aging (BLSA) participants. Methods BMR and medical information were collected at the study entry and approximately every 2 years in 1227 participants (972 men) over a 40-year follow-up. BMR, expressed as kcal/m2/h, was estimated from the basal O2 consumption and CO2 production measured by open-circuit method. Data on all-cause and specific-cause mortality were also obtained. Result BMR declined with age at a rate that accelerated at older ages. Independent of age, participants who died had a higher BMR compared to those who survived. BMR was a significant risk factor for mortality independent of secular trends in mortality and other well-recognized risk factors for mortality, such as age, body mass index, smoking, white blood cell count, and diabetes. BMR was nonlinearly associated with mortality. The lowest mortality rate was found in the BMR range 31.3–33.9 kcal/m2/h. Participants with BMR in the range 33.9–36.4 kcal/m2/h and above the threshold of 36.4 kcal/m2/h experienced 28% (hazard ratio: 1.28; 95% confidence interval, 1.02–1.61) and 53% (hazard ratio: 1.53; 95% confidence interval, 1.19–1.96) higher mortality risk compared to participants with BMR 31.3–33.9 kcal/m2/h. Conclusion We confirm previous findings of an age-related decline of BMR. In our study, a blunted age-related decline in BMR was associated with higher mortality, suggesting that such condition reflects poor health status. PMID:18693224

  12. 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.

  13. The dynamic relationship between cognitive function and walking speed: the English Longitudinal Study of Ageing.

    PubMed

    Gale, Catharine R; Allerhand, Michael; Sayer, Avan Aihie; Cooper, Cyrus; Deary, Ian J

    2014-01-01

    Cross-sectional studies show that older people with better cognition tend to walk faster. Whether this association reflects an influence of fluid cognition upon walking speed, vice versa, a bidirectional relationship or the effect of common causes is unclear. We used linear mixed effects models to examine the dynamic relationship between usual walking speed and fluid cognition, as measured by executive function, verbal memory and processing speed, in 2,654 men and women aged 60 to over 90 years from the English Longitudinal Study of Ageing. There was a bidirectional relationship between walking speed and fluid cognition. After adjusting for age and sex, better performance on executive function, memory and processing speed was associated with less yearly decline in walking speed over the 6-year follow-up period; faster walking speed was associated with less yearly decline in each cognitive domain; and less yearly decline in each cognitive domain was associated with less yearly decline in walking speed. Effect sizes were small. After further adjustment for other covariates, effect sizes were attenuated but most remained statistically significant. We found some evidence that walking speed and the fluid cognitive domains of executive function and processing speed may change in parallel with increasing age. Investigation of the association between walking speed and cognition earlier in life is needed to better understand the origins of this relation and inform the development and timing of interventions.

  14. Effect of material aging on parachute pack life: a synopsis of Sandia National Laboratories studies

    SciTech Connect

    Auerbach, I.; Mead, J.W.; Mead, K.E.; Ericksen, R.H.; Burns, F.B.; Renschler, C.L.

    1984-01-01

    A systematic study of the effects of environmental factors on nylon 66 and Kevlar 29 strength degradation in parachute components is being conducted at Sandia National Laboratories. It includes: (1) accelerated aging studies in air, inert environments, humidity, ozone, and smog; (2) a 25-year surveillance program of parachutes in a variety of natural climatic environments; (3) moisture absorption as a function of humidity; (4) effects of surface coatings normally applied to parachutes; and (5) development of nondestructive evaluation techniques which can be used to map mechanical properties over the entire parachute surface. The accelerated aging and moisture absorption studies show that air, humidity, and smog contribute to degradation. Chemiluminescence, gas chromatographic pyrograms, and uv spectroscopy show promise as nondestructive evaluation techniques.

  15. Ecological risk assessment framework -- the NAS perspective

    SciTech Connect

    Barnthouse, L.W.

    1993-06-01

    A Workshop on Ecological Risk Assessment was held on February 26--March 1, 1991, at Airlie House, Warrenton, Virginia. In addition to presentation and discussion of the case study papers, the workshop included breakout sessions to discuss conceptual and technical aspects of ecological risk assessment. A general consensus emerged that an ecological version of the 1983 framework is desirable and feasible. The committee concluded that the 1983 human health framework could be expanded to accomodate both human health and ecological risk assessment. For general applicability to ecological assessments, the 1983 scheme requires augmentation to address some of the interfaces between science and management, primarily because of the need to focus on appropriate questions relevant to applicable environmental law and policy under different circumstances. Specifically, the scheme needs modification to address (1) the influence of legal and regulatory considerations on the initial stages of ecological risk assessment and (2) the importance of characterizing ecological risks in terms that are intelligible to risk managers. The committee`s opinion is that these augmentations are as important for human health risk assessment as they are for ecological risk assessment. This paper briefly describes the framework recommended by the Committee and compares it to EPA`s recently-published Framework for Ecological Risk Assessment.

  16. F/NAS/ Pressure Temperature Retrieval Techniques

    NASA Technical Reports Server (NTRS)

    Poularikas, Alexander

    1998-01-01

    The purpose of this investigation is to study methods and ways for rapid inversion programs involving the correlated k-method, and to modify the existing programs so that the rapid analysis of data can be accomplished. The earth's atmosphere as well as those around the planets consist of gases which emit radiation in the infrared spectral region, providing wealth of information about chemical and physical processes in the atmosphere. The atmospheric molecular constituents absorb and radiate by vibrational and rotational transitions, and the observed spectra exhibit characteristic spectral features in the region of the electromagnetic spectrum. The observed absorption or thermal emission spectra may be obtained with space-borne high resolution infrared spectrometers the 50-1000 micrometers spectral region. A detailed analysis of the observed spectra leads to information about the atmospheric thermal structure, composition, and the physical and chemical processes. The analytic techniques involve the development of radiative transfer models for the calculation of the observed radiance and transmittances for realistic atmospheric conditions and observational geometries, and the development of inversion methods for retrieval of atmospheric parameters from the observations.

  17. Investigation of risk factors for mortality in aged guide dogs: A retrospective cohort study.

    PubMed

    Hoummady, S; Hua, J; Muller, C; Pouchelon, J L; Blondot, M; Gilbert, C; Desquilbet, L

    2016-09-15

    The overall median lifespan of domestic dogs has been estimated to 9-12 years, but little is known about risk factors for mortality in aged and a priori healthy dogs. The objective of this retrospective cohort study was to determine which characteristics are associated with mortality in aged and a priori healthy guide dogs, in a retrospective cohort study of 116 guide dogs followed from a systematic geriatric examination at the age of 8-10 years old. A geriatric grid collected the clinical data and usual biological parameters were measured at the time of examination. Univariate (Kaplan-Meier estimates) and multivariable (Cox proportional hazard model) survival analyses were used to assess the associations with time to all-cause death. The majority of dogs were Golden Retrievers (n=48) and Labrador Retrievers (n=27). Median age at geriatric examination was 8.9 years. A total of 76 dogs died during follow-up, leading to a median survival time from geriatric examination of 4.4 years. After adjustment for demographic and biological variables, an increased alanine amionotransferase level (adjusted Hazard Ratio (adjusted HR), 6.2; 95% confidence interval [95%CI], 2.0-19.0; P<0.01), presenting skin nodules (adjusted HR, 1.9; 95% CI, 1.0-3.4; P=0.04), and not being a Labrador Retriever (adjusted HR, 3.3; 95%CI, 1.4-10; P<0.01) were independently associated with a shorter time to death. This study documents independent associations of alanine aminotransferase level, skin nodules and breed with mortality in aged guide dogs. These results may be useful for preventive medical care when conducting a geriatric examination in working dogs. PMID:27616361

  18. 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

  19. Early-Onset Thrombocytopenia in Small-For-Gestational-Age Neonates: A Retrospective Cohort Study.

    PubMed

    Fustolo-Gunnink, S F; Vlug, R D; Smits-Wintjens, V E H J; Heckman, E J; Te Pas, A B; Fijnvandraat, K; Lopriore, E

    2016-01-01

    Thrombocytopenia is a common finding in small for gestational age (SGA) neonates and is thought to result from a unique pathophysiologic mechanism related to chronic intrauterine hypoxia. Our objective was to estimate the incidence and severity of early-onset thrombocytopenia in SGA neonates, and to identify risk factors for thrombocytopenia. We performed a retrospective cohort study of all consecutive SGA neonates admitted to our ward and a control group of appropriate for gestational age (AGA) neonates matched for gestational age at birth. Main outcome measures were incidence and severity of thrombocytopenia, hematological and clinical risk factors for thrombocytopenia, and bleeding. A total of 330 SGA and 330 AGA neonates were included, with a mean gestational age at birth of 32.9 ± 4 weeks. Thrombocytopenia (<150x109/L) was found in 53% (176/329) of SGA neonates and 20% (66/330) of AGA neonates (relative risk (RR) 2.7, 95% confidence interval (CI) [2.1, 3.4]). Severe thrombocytopenia (21-50x109/L) occurred in 25 neonates (8%) in the SGA and 2 neonates (1%) in the AGA group (RR 12.5, 95% CI [3.0, 52.5]). Platelet counts <20x109/L were not recorded. Within the SGA group, lower gestational age at birth (p = <0.01) and erythroblastosis (p<0.01) were independently associated with a decrease in platelet count. Platelet count was positively correlated with birth weight centiles. In conclusion, early-onset thrombocytopenia is present in over 50% of SGA neonates and occurs 2.7 times as often as in AGA neonates. Thrombocytopenia is seldom severe and is independently associated with lower gestational age at birth and erythroblastosis. PMID:27177157

  20. Gestational age and newborn size according to parental social mobility: an intergenerational cohort study

    PubMed Central

    Gigante, Denise P; Horta, Bernardo L; Matijasevich, Alicia; Loret de Mola, Christian; Barros, Aluisio J D; Santos, Ina S; Barros, Fernando C; Victora, Cesar G

    2015-01-01

    Background We examined the associations between socioeconomic trajectories from birth to adulthood and gestational age and birth size in the next generation, using linked data from two population-based birth cohorts carried out in a Brazilian city. By comparing socioeconomic trajectories of mothers and fathers, we attempted to identify-specific effects of maternal and paternal socioeconomic trajectory on offspring birth weight, birth length, head circumference and gestational age at birth. Methods 2 population-based birth cohort studies were carried out in 1982 and 2004 in Pelotas (Brazil); 156 mothers and 110 fathers from the earlier cohort had children in 2004. Gestational age and birth length, weight and head circumference were measured. Analyses were carried out separately for mothers and fathers. Mediation analyses assessed the role of birth weight and adult body mass index (BMI). Results Among mothers, but not for fathers, childhood poverty was strongly associated with smaller size in the next generation (about 400 g in weight and 1.5 cm in height) and shorter gestations (about 2 weeks). Adult poverty did not play a role. For mothers, the associations with gestational age, birth length and weight—but not with head circumference—persisted after adjusting for maternal birth weight and for the height and weight of the grandmother. Maternal birth weight did not mediate the observed associations, but high maternal BMI in adulthood was partly responsible for the association with gestational age. Conclusions Strong effects of early poverty on gestational age and birth size in the next generation were observed among mothers, but not among fathers. These findings suggest a specific maternal effect of socioeconomic trajectory, and in particular of early poverty on offspring size and duration of pregnancy. PMID:26109560

  1. Waist circumference and insulin resistance: a community based cross sectional study on reproductive aged Iranian women

    PubMed Central

    2011-01-01

    Background Although the positive relationship between insulin resistance (IR) and central obesity is well known, the direct relationship between waist circumference and IR is not clear yet and there is no consensus regarding the cut off value for waist circumference as a surrogate index for central obesity. The present study was aimed to determine the optimal cut-off value of waist circumference (WC) for predicting IR in reproductive aged Iranian women. Methods Using the stratified, multistage probability cluster sampling method 1036 women were randomly selected from among reproductive aged women of different geographic regions of Iran. Following implementation of exclusion criteria, complete data for 907 women remained for analysis. Insulin resistance was evaluated by the homeostasis model assessment (HOMA-IR) and its cut off value was defined as the 95th percentile of HOMA-IR value for 129 subjects, without any metabolic abnormality. The optimal cut-off of WC in relation to HOMA-IR was calculated based on the receiver operating characteristics (ROC) curve analysis using the Youden index and the area under curve (AUC). Results The mean age of the total sample of 907 subjects was 34.4 ± 7.6 years (range, 18 - 45 years). After adjustment for age the odds ratios (OR) of elevated HOMA-IR were progressively higher with increasing levels of waist circumference; the age adjusted OR of IR for women with WC > 95 cm in comparison to those subjects with WC < 80 cm, was 9.5 (95% CI 5.6-16.1). The optimal cutoff value for WC predicting IR was 88.5 cm; with a sensitivity and specificity of 71% and 64%, respectively. Conclusions Waist circumference is directly related to insulin resistance and the optimal cut-off value for waist circumference reflecting insulin resistance is considered to be 88.5 cm for reproductive aged Iranian women. PMID:21831271

  2. Depositional ages of clastic metasediments from Samos and Syros, Greece: results of a detrital zircon study

    NASA Astrophysics Data System (ADS)

    Löwen, Kersten; Bröcker, Michael; Berndt, Jasper

    2015-01-01

    Siliciclastic metasediments from the islands of Samos and Syros, Cycladic blueschist unit, Greece, were studied to determine maximum sedimentation ages. Four samples from the Ampelos unit on Samos yielded age distribution spectra that range from ~320 Ma to ~3.2 Ga with a dominance of Cambrian-Neoproterozoic zircons (500-1,100 Ma). The youngest well-constrained age groups cluster at 500-550 Ma. Our results allow to link the Samos metasediments with occurrences showing similar age distribution patterns elsewhere in the eastern Mediterranean region (Greece, Turkey, Libya, Israel and Jordan) that record the influx of `Pan-African' detritus. The lack of post-500-Ma zircons in the Samos samples is in marked contrast to the data from Syros that indicates Triassic to Cretaceous depositional ages. The samples from Syros were collected from the matrix of a meta-ophiolitic mélange that is exposed near the top of the metamorphic succession as well as from outcrops representing the basal part of the underlying marble-schist sequence. The zircon populations from Syros were mainly supplied by Mesozoic sources dominated by Triassic protolith ages. Subordinate is the importance of pre-Triassic zircons, but this may reflect bias induced by the research strategy. Sediment accumulation continued until Late Cretaceous time, but the overall contribution of Jurassic to Cretaceous detritus is more limited. Zircon populations are dominated by grains with small degree of rounding suggesting relatively short sediment transportation. Available observations are in accordance with a model suggesting deposition close to the magmatic source rocks.

  3. Resting-State Oscillatory Activity in Children Born Small for Gestational Age: An MEG Study

    PubMed Central

    Boersma, Maria; de Bie, Henrica M. A.; Oostrom, Kim J.; van Dijk, Bob W.; Hillebrand, Arjan; van Wijk, Bernadette C. M.; Delemarre-van de Waal, Henriëtte A.; Stam, Cornelis J.

    2013-01-01

    Growth restriction in utero during a period that is critical for normal growth of the brain, has previously been associated with deviations in cognitive abilities and brain anatomical and functional changes. We measured magnetoencephalography (MEG) in 4- to 7-year-old children to test if children born small for gestational age (SGA) show deviations in resting-state brain oscillatory activity. Children born SGA with postnatally spontaneous catch-up growth [SGA+; six boys, seven girls; mean age 6.3 year (SD = 0.9)] and children born appropriate for gestational age [AGA; seven boys, three girls; mean age 6.0 year (SD = 1.2)] participated in a resting-state MEG study. We calculated absolute and relative power spectra and used non-parametric statistics to test for group differences. SGA+ and AGA born children showed no significant differences in absolute and relative power except for reduced absolute gamma band power in SGA children. At the time of MEG investigation, SGA+ children showed significantly lower head circumference (HC) and a trend toward lower IQ, however there was no association of HC or IQ with absolute or relative power. Except for reduced absolute gamma band power, our findings suggest normal brain activity patterns at school age in a group of children born SGA in which spontaneous catch-up growth of bodily length after birth occurred. Although previous findings suggest that being born SGA alters brain oscillatory activity early in neonatal life, we show that these neonatal alterations do not persist at early school age when spontaneous postnatal catch-up growth occurs after birth. PMID:24068993

  4. 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…

  5. Accounting for age uncertainty in growth modeling, the case study of yellowfin tuna (Thunnus albacares) of the Indian Ocean.

    PubMed

    Dortel, Emmanuelle; Massiot-Granier, Félix; Rivot, Etienne; Million, Julien; Hallier, Jean-Pierre; Morize, Eric; Munaron, Jean-Marie; Bousquet, Nicolas; Chassot, Emmanuel

    2013-01-01

    Age estimates, typically determined by counting periodic growth increments in calcified structures of vertebrates, are the basis of population dynamics models used for managing exploited or threatened species. In fisheries research, the use of otolith growth rings as an indicator of fish age has increased considerably in recent decades. However, otolith readings include various sources of uncertainty. Current ageing methods, which converts an average count of rings into age, only provide periodic age estimates in which the range of uncertainty is fully ignored. In this study, we describe a hierarchical model for estimating individual ages from repeated otolith readings. The model was developed within a Bayesian framework to explicitly represent the sources of uncertainty associated with age estimation, to allow for individual variations and to include knowledge on parameters from expertise. The performance of the proposed model was examined through simulations, and then it was coupled to a two-stanza somatic growth model to evaluate the impact of the age estimation method on the age composition of commercial fisheries catches. We illustrate our approach using the sagittal otoliths of yellowfin tuna of the Indian Ocean collected through large-scale mark-recapture experiments. The simulation performance suggested that the ageing error model was able to estimate the ageing biases and provide accurate age estimates, regardless of the age of the fish. Coupled with the growth model, this approach appeared suitable for modeling the growth of Indian Ocean yellowfin and is consistent with findings of previous studies. The simulations showed that the choice of the ageing method can strongly affect growth estimates with subsequent implications for age-structured data used as inputs for population models. Finally, our modeling approach revealed particularly useful to reflect uncertainty around age estimates into the process of growth estimation and it can be applied to any

  6. Accounting for age uncertainty in growth modeling, the case study of yellowfin tuna (Thunnus albacares) of the Indian Ocean.

    PubMed

    Dortel, Emmanuelle; Massiot-Granier, Félix; Rivot, Etienne; Million, Julien; Hallier, Jean-Pierre; Morize, Eric; Munaron, Jean-Marie; Bousquet, Nicolas; Chassot, Emmanuel

    2013-01-01

    Age estimates, typically determined by counting periodic growth increments in calcified structures of vertebrates, are the basis of population dynamics models used for managing exploited or threatened species. In fisheries research, the use of otolith growth rings as an indicator of fish age has increased considerably in recent decades. However, otolith readings include various sources of uncertainty. Current ageing methods, which converts an average count of rings into age, only provide periodic age estimates in which the range of uncertainty is fully ignored. In this study, we describe a hierarchical model for estimating individual ages from repeated otolith readings. The model was developed within a Bayesian framework to explicitly represent the sources of uncertainty associated with age estimation, to allow for individual variations and to include knowledge on parameters from expertise. The performance of the proposed model was examined through simulations, and then it was coupled to a two-stanza somatic growth model to evaluate the impact of the age estimation method on the age composition of commercial fisheries catches. We illustrate our approach using the sagittal otoliths of yellowfin tuna of the Indian Ocean collected through large-scale mark-recapture experiments. The simulation performance suggested that the ageing error model was able to estimate the ageing biases and provide accurate age estimates, regardless of the age of the fish. Coupled with the growth model, this approach appeared suitable for modeling the growth of Indian Ocean yellowfin and is consistent with findings of previous studies. The simulations showed that the choice of the ageing method can strongly affect growth estimates with subsequent implications for age-structured data used as inputs for population models. Finally, our modeling approach revealed particularly useful to reflect uncertainty around age estimates into the process of growth estimation and it can be applied to any

  7. 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

  8. Estimation of Gestational Age, Using Neonatal Anthropometry: A Cross-sectional Study in India

    PubMed Central

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

    2013-01-01

    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×W–0.781×W2+2.815×HC–0.041×HC2+0.285×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% (±1 week), 75

  9. Reorganization of brain networks in aging: a review of functional connectivity studies

    PubMed Central

    Sala-Llonch, Roser; Bartrés-Faz, David; Junqué, Carme

    2015-01-01

    Healthy aging (HA) is associated with certain declines in cognitive functions, even in individuals that are free of any process of degenerative illness. Functional magnetic resonance imaging (fMRI) has been widely used in order to link this age-related cognitive decline with patterns of altered brain function. A consistent finding in the fMRI literature is that healthy old adults present higher activity levels in some brain regions during the performance of cognitive tasks. This finding is usually interpreted as a compensatory mechanism. More recent approaches have focused on the study of functional connectivity, mainly derived from resting state fMRI, and have concluded that the higher levels of activity coexist with disrupted connectivity. In this review, we aim to provide a state-of-the-art description of the usefulness and the interpretations of functional brain connectivity in the context of HA. We first give a background that includes some basic aspects and methodological issues regarding functional connectivity. We summarize the main findings and the cognitive models that have been derived from task-activity studies, and we then review the findings provided by resting-state functional connectivity in HA. Finally, we suggest some future directions in this field of research. A common finding of the studies included is that older subjects present reduced functional connectivity compared to young adults. This reduced connectivity affects the main brain networks and explains age-related cognitive alterations. Remarkably, the default mode network appears as a highly compromised system in HA. Overall, the scenario given by both activity and connectivity studies also suggests that the trajectory of changes during task may differ from those observed during resting-state. We propose that the use of complex modeling approaches studying effective connectivity may help to understand context-dependent functional reorganizations in the aging process. PMID:26052298

  10. The experiences of women of reproductive age regarding health-promoting behaviours: A qualitative study

    PubMed Central

    2012-01-01

    Background Health promotion is critical for community and family health. Health-promoting behaviours provide solutions for maintaining and promoting health. Although several studies have addressed the frequency and different types of health-promoting behaviours in women, little information is available about their experiences. This study aimed to explore the experiences of women of reproductive age regarding health-promoting behaviours. Methods In the present study, which was conducted in Tehran, Iran, 15 females, who were selected purposefully, participated in individual in-depth, semi-structured interviews. The interviews were recorded, transcribed verbatim, and analysed using conventional content analysis. Results Nine main categories were derived from the analysis, including establishing an appropriate eating pattern, establishing a balanced rest/activity pattern, spirituality, stress management, personal sensitivity and responsibility, establishing an appropriate pattern of social interactions, practicing safe and healthy recreations, feeling improvement in physical-functional health, and feeling improvement in emotional and psychological health. The first 7 categories represent the nature and types of real health-promoting behaviours in women of reproductive age, whereas the last 2 constitute feeling and understanding of the implementation of these behaviours. Conclusion The study findings show that the women experience improvement in physical-functional, emotional, and psychological health by implementing health-promoting behaviours. It is therefore necessary to introduce strategies in the context of the community culture for improving different aspects of health-promoting behaviours in women of reproductive age to maintain and improve their overall health. PMID:22846587

  11. Morphological study of extrauterine length of the fallopian tube at different age group in Bangladeshi people.

    PubMed

    Ara, Z G; Islam, M S; Sultana, S Z; Mannan, S; Zaman, U K; Rahman, M M; Sen, S

    2010-01-01

    This cross sectional descriptive study was done to see the length of the right & left fallopian tube in Bangladeshi female and to increase the knowledge regarding variational anatomy in our country. Sixty post mortem specimens containing uterus, uterine tube, ureter and surrounding structures were collected by non random or purposive sampling technique from cadavers of different age groups and fixed in 10% formol saline solution. This study was carried out in the department of Anatomy of Mymensingh Medical College, Mymensingh from July 2006 to June 2007. Gross and fine dissection was carried out to study the length of fallopian tube (right & left). In this study our findings were compared with those of the standard text books. Maximum length of fallopian tube was found in middle age group (B = 13 to 45 years). It is about 9.19 cm in right side and 8.82 cm in left side. It is also important to note that more kinking was observed in middle age group. PMID:20046169

  12. A prospective study of young females' sexual subjectivity: associations with age, sexual behavior, and dating.

    PubMed

    Zimmer-Gembeck, Melanie J; Ducat, Wendy H; Boislard-Pepin, Marie-Aude

    2011-10-01

    Sexual self-perceptions are important aspects of sexuality, which can undergo significant change during adolescence and early adulthood. The purpose of this study was to describe these changes among girls (N = 251; ages 16-25) over one year, and to examine associations of sexual self-perceptions (sexual subjectivity) with age, sexual behavior, and romantic status. Sexual body-esteem, perceptions of entitlement to desire and pleasure, sexual efficacy, and sexual self-reflection were investigated as elements of sexual subjectivity. All sexual subjectivity elements were higher among girls who had more sexual experience and/or had steady romantic partners during the study. Perception of entitlement to desire and pleasure increased over time, whereas sexual body-esteem showed the most stability and had minimal associations with sexual or romantic experiences. The greatest increases in sexual subjectivity were found among girls who began the study with the least sociosexual experience and self-reflection also increased for girls who had first coitus after the start of the study. Overall, girls who had sexual intercourse the earliest (before age 16) had the highest sexual subjectivity, but sexual subjectivity increased the most among girls without coital experience or who had more recent first coitus.

  13. Age and diabetes related changes of the retinal capillaries: An ultrastructural and immunohistochemical study.

    PubMed

    Bianchi, Enrica; Ripandelli, Guido; Taurone, Samanta; Feher, Janos; Plateroti, Rocco; Kovacs, Illes; Magliulo, Giuseppe; Orlando, Maria Patrizia; Micera, Alessandra; Battaglione, Ezio; Artico, Marco

    2016-03-01

    Normal human aging and diabetes are associated with a gradual decrease of cerebral flow in the brain with changes in vascular architecture. Thickening of the capillary basement membrane and microvascular fibrosis are evident in the central nervous system of elderly and diabetic patients. Current findings assign a primary role to endothelial dysfunction as a cause of basement membrane (BM) thickening, while retinal alterations are considered to be a secondary cause of either ischemia or exudation. The aim of this study was to reveal any initial retinal alterations and variations in the BM of retinal capillaries during diabetes and aging as compared to healthy controls. Moreover, we investigated the potential role of vascular endothelial growth factor (VEGF) and pro-inflammatory cytokines in diabetic retina.Transmission electron microscopy (TEM) was performed on 46 enucleated human eyes with particular attention to alterations of the retinal capillary wall and Müller glial cells. Inflammatory cytokines expression in the retina was investigated by immunohistochemistry.Our electron microscopy findings demonstrated that thickening of the BM begins primarily at the level of the glial side of the retina during aging and diabetes. The Müller cells showed numerous cytoplasmic endosomes and highly electron-dense lysosomes which surrounded the retinal capillaries. Our study is the first to present morphological evidence that Müller cells start to deposit excessive BM material in retinal capillaries during aging and diabetes. Our results confirm the induction of pro-inflammatory cytokines TNF-α and IL-1β within the retina as a result of diabetes.These observations strongly suggest that inflammatory cytokines and changes in the metabolism of Müller glial cells rather than changes in of endothelial cells may play a primary role in the alteration of retinal capillaries BM during aging and diabetes. PMID:26604209

  14. 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

  15. Neuroimaging of Cognitive Dysfunction and Depression in Aging Retired NFL Players: A cross-sectional study

    PubMed Central

    Hart, John; Kraut, Michael A.; Womack, Kyle B.; Strain, Jeremy; Didehbani, Nyaz; Bartz, Elizabeth; Conover, Heather; Mansinghani, Sethesh; Lu, Hanzhang; Cullum, C. Munro

    2013-01-01

    Objective To assess for the presence of cognitive impairment and depression in aging former NFL players, and identify neuroimaging correlates of these dysfunctions. Design Comparison of aging NFL players with cognitive impairment and depression to those without these dysfunctions and with matched healthy controls Setting Research center in the North Texas region of the United States. Patients We performed a cross-sectional study of retired professional football players with and without a history of concussion recruited from the North Texas region, along with age-, education-, and IQ-matched controls. We studied thirty-four retired NFL players (mean age 62) neurologically and neuropsychologically. A subset of 26 also underwent detailed neuroimaging; imaging data in this subset were compared to imaging data acquired in 26 healthy matched controls. Main Outcome Measures Neuropsychological measures, clinical diagnoses of depression, neuroimaging measures of white matter pathology, and a measure of cerebral blood flow (CBF). Results Of the 34 participants, 20 were cognitively normal, 4 were diagnosed with a fixed cognitive deficit, 8 with Mild Cognitive Impairment, and 2 with dementia; 8 were diagnosed with depression. Of the subgroup in which neuroimaging data were acquired, cognitively impaired (CI) participants showed greatest deficits on tests of naming, word finding, and visual/verbal episodic memory. We found significant differences in white matter abnormalities in CI players and depressed players compared to their respective controls. Regional blood flow differences in the CI group (left temporal pole, inferior parietal lobule, superior temporal gyrus) corresponded to regions associated with impaired neurocognitive performance (problems with memory, naming and word finding). Conclusions Cognitive deficits and depression appear to be more common in aging NFL players compared to controls. These deficits are correlated with white matter abnormalities and changes in

  16. NAS Grid Benchmarks: A Tool for Grid Space Exploration

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

    We present an approach for benchmarking services provided by computational Grids. It is based on the NAS Parallel Benchmarks (NPB) and is called NAS Grid Benchmark (NGB) in this paper. We present NGB as a data flow graph encapsulating an instance of an NPB code in each graph node, which communicates with other nodes by sending/receiving initialization data. These nodes may be mapped to the same or different Grid machines. Like NPB, NGB will specify several different classes (problem sizes). NGB also specifies the generic Grid services sufficient for running the bench-mark. The implementor has the freedom to choose any specific Grid environment. However, we describe a reference implementation in Java, and present some scenarios for using NGB.

  17. Capturing heterogeneous group differences using mixture-of-experts: Application to a study of aging.

    PubMed

    Eavani, Harini; Hsieh, Meng Kang; An, Yang; Erus, Guray; Beason-Held, Lori; Resnick, Susan; Davatzikos, Christos

    2016-01-15

    In MRI studies, linear multi-variate methods are often employed to identify regions or connections that are affected due to disease or normal aging. Such linear models inherently assume that there is a single, homogeneous abnormality pattern that is present in all affected individuals. While kernel-based methods can implicitly model a non-linear effect, and therefore the heterogeneity in the affected group, extracting and interpreting information about affected regions is difficult. In this paper, we present a method that explicitly models and captures heterogeneous patterns of change in the affected group relative to a reference group of controls. For this purpose, we use the Mixture-of-Experts (MOE) framework, which combines unsupervised modeling of mixtures of distributions with supervised learning of classifiers. MOE approximates the non-linear boundary between the two groups with a piece-wise linear boundary, thus allowing discovery of multiple patterns of group differences. In the case of patient/control comparisons, each such pattern aims to capture a different dimension of a disease, and hence to identify patient subgroups. We validated our model using multiple simulation scenarios and performance measures. We applied this method to resting state functional MRI data from the Baltimore Longitudinal Study of Aging, to investigate heterogeneous effects of aging on brain function in cognitively normal older adults (>85years) relative to a reference group of normal young to middle-aged adults (<60years). We found strong evidence for the presence of two subgroups of older adults, with similar age distributions in each subgroup, but different connectivity patterns associated with aging. While both older subgroups showed reduced functional connectivity in the Default Mode Network (DMN), increases in functional connectivity within the pre-frontal cortex as well as the bilateral insula were observed only for one of the two subgroups. Interestingly, the subgroup

  18. [Anti-aging studies on the senescence accelerated mouse (SAM) strains].

    PubMed

    Takahashi, Ryoya

    2010-01-01

    Senescence accelerated mouse (SAM), a murine model of accelerated senescence, was established by Toshio Takeda and colleagues. SAM consists of series of SAMP (prone) and SAMR (resistant) lines. All SAMP lines (from SAMP1 to SAMP11) are characterized by accelerated accumulation of senile features, earlier onset and faster progress of age-associated pathological phenotypes, such as amyloidosis, impaired immune response, senile osteoporosis and deficits in learning and memory. These SAMP lines are useful for evaluation of putative anti-aging therapies. For example, SAMP1 line is used to study the anti-aging effect of the antioxidant containing foods and various anti-oxidants, such as coenzyme Q10, vitamin C, lycopene. SAMP8 line exhibiting an early onset of impaired learning and memory is often used for test strategies for therapeutic intervention of dementia of early onset. SAMP6 is used as an animal model for developing new strategies for the treatment of osteoporosis in humans. Various lines of SAM (P1, P6, P8, P10 and R1) are now commercially available for research. In this review, I will briefly introduce various usages of SAM in anti-aging research. PMID:20046059

  19. 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.

  20. The global impact of income inequality on health by age: an observational study

    PubMed Central

    Mitchell, Richard; Pearce, Jamie

    2007-01-01

    Objectives To explore whether the apparent impact of income inequality on health, which has been shown for wealthier nations, is replicated worldwide, and whether the impact varies by age. Design Observational study. Setting 126 countries of the world for which complete data on income inequality and mortality by age and sex were available around the year 2002 (including 94.4% of world human population). Data sources Data on mortality were from the World Health Organization and income data were taken from the annual reports of the United Nations Development Programme. Main outcome measures Mortality in 5-year age bands for each sex by income inequality and income level. Results At ages 15-29 and 25-39 variations in income inequality seem more closely correlated with mortality worldwide than do variations in material wealth. This relation is especially strong among the poorest countries in Africa. Mortality is higher for a given level of overall income in more unequal nations. Conclusions Income inequality seems to have an influence worldwide, especially for younger adults. Social inequality seems to have a universal negative impact on health. PMID:17954512

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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. PMID:27010530

  6. Depression, socioeconomic status, age, and marital status in black women: a national study.

    PubMed

    Scarinci, Isabel C; Beech, Bettina M; Naumann, Wendy; Kovach, Kristen W; Pugh, Letha; Fapohunda, Bolaji

    2002-01-01

    This study examined the relationship between an array of socioeconomic status (SES) indicators and depression among Black women; determined which SES indicator was most strongly associated with depression; and examined whether the relationship between SES and depression was the same across age and marital status. A sample of 1,407 Black women recruited through the National Black Women's Health Project completed a survey on psychological well-being. Independent variables included income, education, median income within zip codes, marital status, and age. The dependent variable was depression as measured by the CES-D. The average CES-D score among participants was 12.67 (SD = 10.54), and 31.9% screened positive for depression. An inverse relationship was found between income and education and depression. The higher the yearly household income and education level the lower the scores on the CES-D. Income was the SES indicator most strongly associated with depression. Younger women had higher scores on the CES-D. Never-married women exhibited significantly higher levels of depression compared to women who were married or living together with an intimate partner. There were no significant interactions between SES indicators, age, and marital status. These findings suggest that income, education level, marital status, and age may be important demographic variables to consider when designing interventions to address depression among Black women.

  7. 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.

  8. A Longitudinal Study of Cardiovascular Stability in Active Men Aged 45 to 65 Years.

    PubMed

    Kasch, F W; Wallace, J P; Van Camp, S P; Verity, L

    1988-01-01

    In brief: Cross-sectional studies of physical performance generally show a linear decline in maximum aerobic power (V O2 max) with increasing age (about 1% to 2% per year). In the study described in this article, 15 men were serially followed for 20 years. They performed exercises consisting of walking, running, swimming, and cycling for an average of 3.6 days per week and requiring an energy expenditure of 2,104 kcal per week. Over the 20 years, directly measured V O2 max declined 12% (from 44.4 to 38.9 ml· kg(-1)· min(-1), or 0.27 ml· kg(-1)· min(-1) per year). Essentially no differences were seen in resting heart rate or arterial blood pressure. The authors conclude that physical training forestalls the decline in V O2 max until at least age 65. PMID:27427109

  9. A transmission electron microscopy study of mineralization in age-induced transparent dentin.

    PubMed

    Porter, Alexandra E; Nalla, Ravi K; Minor, Andrew; Jinschek, Joerg R; Kisielowski, Christian; Radmilovic, Velimir; Kinney, John H; Tomsia, Antoni P; Ritchie, R O

    2005-12-01

    It is known that fractures are more likely to occur in altered teeth, particularly following restoration or endodontic repair; consequently, it is important to understand the structure of altered forms of dentin, the most abundant tissue in the human tooth, in order to better define the increased propensity for such fractures. Transparent (or sclerotic) dentin, wherein the dentinal tubules become occluded with mineral as a natural progressive consequence of aging, is one such altered form. In the present study, high-resolution transmission electron microscopy is used to investigate the effect of aging on the mineral phase of dentin. Such studies revealed that the intertubular mineral crystallites were smaller in transparent dentin, and that the intratubular mineral (larger crystals deposited within the tubules) was chemically similar to the surrounding intertubular mineral. Exit-wave reconstructed lattice-plane images suggested that the intratubular mineral had nanometer-size grains. These observations support a "dissolution and reprecipitation" mechanism for the formation of transparent dentin.

  10. Molecular ageing: Free radical initiated epimerization of thymopentin - A case study

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    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-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-Asp3 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.

  11. 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.

  12. Lifetime Occupational Physical Activity and Musculoskeletal Aging in Middle-Aged Men and Women in Denmark: Retrospective Cohort Study Protocol and Methods

    PubMed Central

    Mortensen, Ole Steen; Reventlow, Susanne; Skov, Peder Georg; Andersen, Johan Hviid; Rubak, Tine Steen; Hansen, Åse Marie; Andersen, Lars L; Lund, Rikke; Osler, Merete; Christensen, Ulla; Avlund, Kirsten

    2012-01-01

    Background Physical function is essential for performing most aspects of daily life and musculoskeletal aging leads to a decline in physical function. The onset and rate of this process vary and are influenced by environmental, genetic, and hormonal factors. Although everyone eventually experiences musculoskeletal aging, it is beneficial to study the factors that influence the aging process in order to prevent disability. The role of occupational physical activity in the musculoskeletal aging process is unclear. In the past, hard physical work was thought to strengthen the worker, but current studies in this field fail to find a training effect in jobs with a high level of occupational physical activity. Objective The aim of this study is to examine the influence of lifetime occupational physical activity on physical function in midlife. The study follows the “occupational life-course perspective,” emphasizing the importance of occupational exposures accumulated throughout life on the musculoskeletal aging process taking socioeconomic and lifestyle factors into consideration. Methods This study is a retrospective cohort study including a cross-sectional measurement of physical function in 5000 middle-aged Danes. Data was obtained from the Copenhagen Aging and Midlife Biobank (CAMB) which is based on three existing Danish cohorts. Using questionnaire information about the five longest-held occupations, the job history was coded from the Danish version of the International Standard Classification of Occupations (D-ISCO 88) and a job exposure matrix containing information about occupational physical activity in Danish jobs was applied to the dataset. The primary outcomes are three tests of physical function: handgrip strength, balance, and chair rise. In the analyses, we will compare physical function in midlife according to accumulated exposure to high levels of occupational physical activity. Conclusions We have a unique opportunity to study the influence of

  13. NASA UAS Integration into the NAS Project: Human Systems Integration

    NASA Technical Reports Server (NTRS)

    Shively, Jay

    2016-01-01

    This presentation provides an overview of the work the Human Systems Integration (HSI) sub-project has done on detect and avoid (DAA) displays while working on the UAS (Unmanned Aircraft System) Integration into the NAS project. The most recent simulation on DAA interoperability with Traffic Collision Avoidance System (TCAS) is discussed in the most detail. The relationship of the work to the larger UAS community and next steps are also detailed.

  14. Evaluating the Information Power Grid using the NAS Grid Benchmarks

    NASA Technical Reports Server (NTRS)

    VanderWijngaartm Rob F.; Frumkin, Michael A.

    2004-01-01

    The NAS Grid Benchmarks (NGB) are a collection of synthetic distributed applications designed to rate the performance and functionality of computational grids. We compare several implementations of the NGB to determine programmability and efficiency of NASA's Information Power Grid (IPG), whose services are mostly based on the Globus Toolkit. We report on the overheads involved in porting existing NGB reference implementations to the IPG. No changes were made to the component tasks of the NGB can still be improved.

  15. Performance and Scalability of the NAS Parallel Benchmarks in Java

    NASA Technical Reports Server (NTRS)

    Frumkin, Michael A.; Schultz, Matthew; Jin, Haoqiang; Yan, Jerry; Biegel, Bryan A. (Technical Monitor)

    2002-01-01

    Several features make Java an attractive choice for scientific applications. In order to gauge the applicability of Java to Computational Fluid Dynamics (CFD), we have implemented the NAS (NASA Advanced Supercomputing) 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 position Java closer to Fortran in the competition for scientific applications.

  16. Implementation of the NAS Parallel Benchmarks in Java

    NASA Technical Reports Server (NTRS)

    Frumkin, Michael A.; Schultz, Matthew; Jin, Haoqiang; Yan, Jerry; Biegel, Bryan (Technical Monitor)

    2002-01-01

    Several features make Java an attractive choice for High Performance Computing (HPC). In order to gauge the applicability of Java to Computational Fluid Dynamics (CFD), we have implemented the NAS (NASA Advanced Supercomputing) 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 position Java closer to Fortran in the competition for CFD applications.

  17. HABITAT: A longitudinal multilevel study of physical activity change in mid-aged adults

    PubMed Central

    Burton, Nicola W; Haynes, Michele; Wilson, Lee-Ann M; Giles-Corti, Billie; Oldenburg, Brian F; Brown, Wendy J; Giskes, Katrina; Turrell, Gavin

    2009-01-01

    Background Little is known about the patterns and influences of physical activity change in mid-aged adults. This study describes the design, sampling, data collection, and analytical plan of HABITAT, an innovative study of (i) physical activity change over five years (2007–2011) in adults aged 40–65 years at baseline, and (ii) the relative contribution of psychological variables, social support, neighborhood perceptions, area-level factors, and sociodemographic characteristics to physical activity change. Methods/Design HABITAT is a longitudinal multi-level study. 1625 Census Collection Districts (CCDs) in Brisbane, Australia were ranked by their index of relative socioeconomic disadvantage score, categorized into deciles, and 20 CCDs from each decile were selected to provide 200 local areas for study inclusion. From each of the 200 CCDs, dwellings with individuals aged between 40–65 years (in 2007) were identified using electoral roll data, and approximately 85 people per CCD were selected to participate (N = 17,000). A comprehensive Geographic Information System (GIS) database has been compiled with area-level information on public transport networks, footpaths, topography, traffic volume, street lights, tree coverage, parks, public services, and recreational facilities Participants are mailed a questionnaire every two years (2007, 2009, 2011), with items assessing physical activity (general walking, moderate activity, vigorous activity, walking for transport, cycling for transport, recreational activities), sitting time, perceptions of neighborhood characteristics (traffic, pleasant surroundings, streets, footpaths, crime and safety, distance to recreational and business facilities), social support, social cohesion, activity-related cognitions (attitudes, efficacy, barriers, motivation), health, and sociodemographic characteristics. Analyses will use binary and multinomial logit regression models, as well as generalized linear latent growth models

  18. 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…

  19. 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…

  20. Applicability of Greulich-Pyle and Tanner-Whitehouse grading methods to MRI when assessing hand bone age in forensic age estimation: A pilot study.

    PubMed

    Urschler, Martin; Krauskopf, Astrid; Widek, Thomas; Sorantin, Erich; Ehammer, Thomas; Borkenstein, Martin; Yen, Kathrin; Scheurer, Eva

    2016-09-01

    Determination of skeletal development is a key pillar in forensic age estimation of living persons. Radiological assessment of hand bone age is widely used until the age of about 17-18 years, applying visual grading techniques to hand radiographs. This study investigated whether Greulich-Pyle (GP) and Tanner-Whitehouse (TW2) grading can be equally used for magnetic resonance imaging (MRI) data, which would offer the huge benefit of avoiding ionizing radiation. In 18 subjects aged between 7 and 17 years a radiograph and an MRI scan of the hand were performed. Epiphyseal ossification of hand bones was rated by two blinded radiologists with both GP and TW2. Correlation between hand MRIs and radiographs was analyzed by linear regression and inter-observer agreement was assessed. Correlation between age estimates from MRI and radiographs was high for both GP (r(2)=0.98) and TW2 (r(2)=0.93). MRI showed a tendency to estimate age slightly lower for 14-18 year-olds, which would be favorable regarding majority age determination in case this result could be reproduced using a currently not existing reference estimation method based on MRI data. Inter-observer agreement was similar for GP in radiographs and MRI, while for TW2, agreement in MRI was lower than in radiographs. In spite of limitations regarding sample size and recruited subjects, our results indicate that the use of GP and TW2 on MRI data offers the possibility of hand bone age estimation without the need for ionizing radiation. PMID:27344264

  1. Risk Factors for Late-Life Cognitive Decline and Variation with Age and Sex in the Sydney Memory and Ageing Study

    PubMed Central

    Lipnicki, Darren M.; Sachdev, Perminder S.; Crawford, John; Reppermund, Simone; Kochan, Nicole A.; Trollor, Julian N.; Draper, Brian; Slavin, Melissa J.; Kang, Kristan; Lux, Ora; Mather, Karen A.; Brodaty, Henry

    2013-01-01

    Introduction An aging population brings increasing burdens and costs to individuals and society arising from late-life cognitive decline, the causes of which are unclear. We aimed to identify factors predicting late-life cognitive decline. Methods Participants were 889 community-dwelling 70–90-year-olds from the Sydney Memory and Ageing Study with comprehensive neuropsychological assessments at baseline and a 2-year follow-up and initially without dementia. Cognitive decline was considered as incident mild cognitive impairment (MCI) or dementia, as well as decreases in attention/processing speed, executive function, memory, and global cognition. Associations with baseline demographic, lifestyle, health and medical factors were determined. Results All cognitive measures showed decline and 14% of participants developed incident MCI or dementia. Across all participants, risk factors for decline included older age and poorer smelling ability most prominently, but also more education, history of depression, being male, higher homocysteine, coronary artery disease, arthritis, low health status, and stroke. Protective factors included marriage, kidney disease, and antidepressant use. For some of these factors the association varied with age or differed between men and women. Additional risk and protective factors that were strictly age- and/or sex-dependent were also identified. We found salient population attributable risks (8.7–49.5%) for older age, being male or unmarried, poor smelling ability, coronary artery disease, arthritis, stroke, and high homocysteine. Discussion Preventing or treating conditions typically associated with aging might reduce population-wide late-life cognitive decline. Interventions tailored to particular age and sex groups may offer further benefits. PMID:23799051

  2. Applicability of Greulich-Pyle and Tanner-Whitehouse grading methods to MRI when assessing hand bone age in forensic age estimation: A pilot study.

    PubMed

    Urschler, Martin; Krauskopf, Astrid; Widek, Thomas; Sorantin, Erich; Ehammer, Thomas; Borkenstein, Martin; Yen, Kathrin; Scheurer, Eva

    2016-09-01

    Determination of skeletal development is a key pillar in forensic age estimation of living persons. Radiological assessment of hand bone age is widely used until the age of about 17-18 years, applying visual grading techniques to hand radiographs. This study investigated whether Greulich-Pyle (GP) and Tanner-Whitehouse (TW2) grading can be equally used for magnetic resonance imaging (MRI) data, which would offer the huge benefit of avoiding ionizing radiation. In 18 subjects aged between 7 and 17 years a radiograph and an MRI scan of the hand were performed. Epiphyseal ossification of hand bones was rated by two blinded radiologists with both GP and TW2. Correlation between hand MRIs and radiographs was analyzed by linear regression and inter-observer agreement was assessed. Correlation between age estimates from MRI and radiographs was high for both GP (r(2)=0.98) and TW2 (r(2)=0.93). MRI showed a tendency to estimate age slightly lower for 14-18 year-olds, which would be favorable regarding majority age determination in case this result could be reproduced using a currently not existing reference estimation method based on MRI data. Inter-observer agreement was similar for GP in radiographs and MRI, while for TW2, agreement in MRI was lower than in radiographs. In spite of limitations regarding sample size and recruited subjects, our results indicate that the use of GP and TW2 on MRI data offers the possibility of hand bone age estimation without the need for ionizing radiation.

  3. 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.

  4. 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. PMID:18263600

  5. 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. PMID:26655068

  6. 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.

  7. 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

  8. 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.

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

    PubMed

    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

  10. A Feasibility Study of Wearable Activity Monitors for Pre-Adolescent School-Age Children

    PubMed Central

    Van Loan, Marta; German, J. Bruce

    2014-01-01

    Introduction 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. Methods A qualitative study was conducted with 25 children aged 7 to 10 years to assess acceptability and compliance of wearable activity devices in this age group. During March through August 2012, children participated in a 4-week study of 3 accelerometer models and a heart rate monitor. Children were asked to use a different device each week for 7 consecutive days. Children and their parents completed structured interviews after using each device; they also completed a final exit interview. Results The wrist-worn Polar Active was the device most preferred by children and was associated with the highest level of compliance. Devices that are comfortable to wear, fit properly, have engaging features, and are waterproof increase feasibility and are associated with higher levels of compliance. Conclusion The wrist-worn device was the most feasible for measuring physical activity among children aged 7 to 10 years. These findings will inform researchers in selecting tools for measuring children’s physical activity. PMID:24854236

  11. 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.

  12. Hybrid Network Architectures for the Next Generation NAS

    NASA Technical Reports Server (NTRS)

    Madubata, Christian

    2003-01-01

    To meet the needs of the 21st Century NAS, an integrated, network-centric infrastructure is essential that is characterized by secure, high bandwidth, digital communication systems that support precision navigation capable of reducing position errors for all aircraft to within a few meters. This system will also require precision surveillance systems capable of accurately locating all aircraft, and automatically detecting any deviations from an approved path within seconds and be able to deliver high resolution weather forecasts - critical to create 4- dimensional (space and time) profiles for up to 6 hours for all atmospheric conditions affecting aviation, including wake vortices. The 21st Century NAS will be characterized by highly accurate digital data bases depicting terrain, obstacle, and airport information no matter what visibility conditions exist. This research task will be to perform a high-level requirements analysis of the applications, information and services required by the next generation National Airspace System. The investigation and analysis is expected to lead to the development and design of several national network-centric communications architectures that would be capable of supporting the Next Generation NAS.

  13. Graded band gap GaInNAs solar cells

    SciTech Connect

    Langer, F.; Perl, S.; Kamp, M.; Höfling, S.

    2015-06-08

    Dilute nitride GaInN(Sb)As with a band gap (E{sub g}) of 1.0 eV is a promising material for the integration in next generation multijunction solar cells. We have investigated the effect of a compositionally graded GaInNAs absorber layer on the spectral response of a GaInNAs sub cell. We produced band gap gradings (ΔE{sub g}) of up to 39 meV across a 1 μm thick GaInNAs layer. Thereby, the external quantum efficiency—compared to reference cells—was increased due to the improved extraction of photo-generated carriers from 34.0% to 36.7% for the wavelength range from 900 nm to 1150 nm. However, this device figure improvement is accompanied by a small decrease in the open circuit voltage of about 20 mV and the shift of the absorption edge to shorter wavelengths.

  14. Autotasked Performance in the NAS Workload: A Statistical Analysis

    NASA Technical Reports Server (NTRS)

    Carter, R. L.; Stockdale, I. E.; Kutler, Paul (Technical Monitor)

    1998-01-01

    A statistical analysis of the workload performance of a production quality FORTRAN code for five different Cray Y-MP hardware and system software configurations is performed. The analysis was based on an experimental procedure that was designed to minimize correlations between the number of requested CPUs and the time of day the runs were initiated. Observed autotasking over heads were significantly larger for the set of jobs that requested the maximum number of CPUs. Speedups for UNICOS 6 releases show consistent wall clock speedups in the workload of around 2. which is quite good. The observed speed ups were very similar for the set of jobs that requested 8 CPUs and the set that requested 4 CPUs. The original NAS algorithm for determining charges to the user discourages autotasking in the workload. A new charging algorithm to be applied to jobs run in the NQS multitasking queues also discourages NAS users from using auto tasking. The new algorithm favors jobs requesting 8 CPUs over those that request less, although the jobs requesting 8 CPUs experienced significantly higher over head and presumably degraded system throughput. A charging algorithm is presented that has the following desirable characteristics when applied to the data: higher overhead jobs requesting 8 CPUs are penalized when compared to moderate overhead jobs requesting 4 CPUs, thereby providing a charging incentive to NAS users to use autotasking in a manner that provides them with significantly improved turnaround while also maintaining system throughput.

  15. Increasing age and experience: are both protective against motorcycle injury? A case-control study

    PubMed Central

    Mullin, B.; Jackson, R.; Langley, J.; Norton, R.

    2000-01-01

    Objectives—To assess the associations between age, experience, and motorcycle injury. Setting—Motorcycle riding on non-residential roads between 6 am and midnight over a three year period from February 1993 in Auckland, New Zealand. Methods—A population based case-control study was conducted. Cases were 490 motorcycle drivers involved in a crash and controls were 1518 drivers identified at random roadside surveys. Crash involvement was defined in terms of a motorcycle crash resulting in either a driver or pillion passenger being killed, hospitalised, or presenting to a public hospital emergency department with an injury severity score ≥5. Results—There was a strong and consistent relationship between increasing driver age and decreasing risk of moderate to fatal injury. In multivariate analyses, drivers older than 25 years had more than 50% lower risk than those aged from 15–19 years (odds ratio (OR) 0.46; 95% confidence interval (CI) 0.26 to 0.81). In univariate analyses, a protective effect from riding more than five years compared with less than two years was observed. However, this protection was not sustained when driver age and other potential confounding variables were included in the analyses. Familiarity with the specific motorcycle was the only experience measure associated with a strong protective effect (OR (≥10 000 km experience) 0.52; 95% CI 0.35 to 0.79) in multivariate analyses. Conclusions—Current licensing regulations should continue to emphasise the importance of increased age and might consider restrictions that favour experience with a specific motorcycle. PMID:10728539

  16. Understanding the Experience of Age-Related Vestibular Loss in Older Individuals: A Qualitative Study

    PubMed Central

    Li, Carol; Bridges, John F. P.; Agrawal, Yuri

    2016-01-01

    Background Inner ear balance (or vestibular) function declines with age and is associated with decreased mobility and an increased risk of falls in older individuals. We sought to understand the lived experience of older adults with vestibular loss in order to improve care in this population. Methods Qualitative data were derived from semi-structured interviews of individuals aged 65 years or older presenting to the Balance and Falls Prevention Clinic from February 1, 2014 to March 30, 2015 for evaluation of age-related vestibular loss. Transcripts were analyzed using interpretive phenomenological analysis. We created a taxonomy of overarching superordinate themes based on the World Health Organization's International Classification of Functioning, Disability, and Health (ICF) Framework, and classified key dimensions within each of these themes. Results Sixteen interviews were conducted with individuals (mean age 76.0 years, 75 % female) with age-related vestibular loss. The three superordinate themes and associated key dimensions were (1) body impairment (including depression, fatigue, fear/anxiety, and problems with concentrating and memory); (2) activity limitation and participation restriction (isolation, needing to stop in the middle of activities, reduced participation relative to expectations, reduced ability to drive or travel, and problems with bending/looking up, standing, and walking); and (3) environmental influences (needing help with daily activities). All participants reported difficulty walking. Conclusions Older adults report that vestibular loss impacts their body functioning and restricts their participation in activities. The specific key dimensions uncovered by this qualitative study can be used to evaluate care from the patient's perspective. PMID:26739817

  17. Menopausal Age and Chronic Diseases in Elderly Women: A Cross-Sectional Study in Northeast China

    PubMed Central

    Fu, Yingli; Yu, Yaqin; Wang, Shibin; Kanu, Joseph Sam; You, Yueyue; Liu, Yingyu; Zhang, Yangyu; Liu, Yawen; Li, Bo; Tao, Yuchun; Kou, Changgui

    2016-01-01

    Many factors affect menopausal age, and early or late onset of menopause may be associated with many chronic health problems. However, limited data are available regarding this phenomenon in the Northeast China population. For this study, 2011 elderly women were selected as a sample from participants in a cross-sectional survey performed using stratified, clustered multistage, and random sampling methods. Early menopause was more prevalent in subjects born from 1943 to 1947 (OR = 1.708, 95% CI = 1.205, 2.420) and 1933 to 1937 (OR = 2.445, 95% CI: 1.525, 3.921) and in physical laborers (OR = 1.413, 95% CI = 1.021, 1.957). Women with less than nine years of education (OR = 0.515, 95% CI: 0.327, 0.812) and who were current smokers (OR = 0.577, 95% CI: 0.347, 0.959) were less likely to have late menopause. BMIs between 25 and 30 (OR = 1.565, 95% CI: 1.152, 2.125) and greater than 30 (OR = 2.440, 95% CI: 1.482, 4.016) were associated with later menopausal age. Late menopause was positively associated with diabetes (OR = 1.611, 95% CI: 1.142, 2.274) but protective against chronic gastroenteritis/peptic ulcers (OR = 0.533, 95% CI: 0.333, 0.855). Results showed that (1) Being born in an earlier year, having a lower education, and engaging in physical labor were associated with an earlier menopausal age, while a higher BMI was associated with a later menopausal age; and that (2) menopausal age was associated with diabetes and gastroenteritis in elderly women living in Northeast China. PMID:27669270

  18. Stereopsis Results at 4.5 Years of Age in the Infant Aphakia Treatment Study

    PubMed Central

    Hartmann, E. Eugenie; Stout, Ann U.; Lynn, Michael J.; Yen, Kimberly G.; Kruger, Stacey J.; Lambert, Scott R.

    2014-01-01

    Purpose To determine whether stereopsis of infants treated for monocular cataracts varies with the type of optical correction used. Design Randomized prospective clinical trial Methods The Infant Aphakia Treatment Study randomized 114 patients with unilateral cataracts at age 1 to 7 months to either primary intraocular lens (IOL) or contact lens correction. At 4.5 years of age a masked examiner assessed stereopsis on these patients using three different tests: 1) Frisby; 2) Randot Preschool; and 3) Titmus fly. Results Twenty-eight patients (25%) had a positive response to at least one of the stereopsis tests. There was no statistically significant difference in stereopsis between the two treatment groups. Frisby (contact lens, 6 (11%); IOL, 7 (13%); p=0.99), Randot (contact lens, 3 (6%); IOL, 1 (2%); p=0.62) or Titmus: (contact lens, 8 (15%); IOL, 13 (23%); p=0.34). The median age at surgery for patients with stereopsis was younger than for those without stereopsis (1.2 versus 2.4 months; p=0.002). The median visual acuity for patients with stereopsis was better than for those without stereopsis (20/40 vs. 20/252; p=0.0003). Conclusion The type of optical correction did not influence stereopsis outcomes. However, two other factors did: age at surgery and visual acuity in the treated eye at age 4.5 years. Early surgery for unilateral congenital cataract and the presence of visual acuity better than or equal to 20/40 appear to be more important than the type of initial optical correction used for the development of stereopsis. PMID:25261241

  19. Menopausal Age and Chronic Diseases in Elderly Women: A Cross-Sectional Study in Northeast China.

    PubMed

    Fu, Yingli; Yu, Yaqin; Wang, Shibin; Kanu, Joseph Sam; You, Yueyue; Liu, Yingyu; Zhang, Yangyu; Liu, Yawen; Li, Bo; Tao, Yuchun; Kou, Changgui

    2016-01-01

    Many factors affect menopausal age, and early or late onset of menopause may be associated with many chronic health problems. However, limited data are available regarding this phenomenon in the Northeast China population. For this study, 2011 elderly women were selected as a sample from participants in a cross-sectional survey performed using stratified, clustered multistage, and random sampling methods. Early menopause was more prevalent in subjects born from 1943 to 1947 (OR = 1.708, 95% CI = 1.205, 2.420) and 1933 to 1937 (OR = 2.445, 95% CI: 1.525, 3.921) and in physical laborers (OR = 1.413, 95% CI = 1.021, 1.957). Women with less than nine years of education (OR = 0.515, 95% CI: 0.327, 0.812) and who were current smokers (OR = 0.577, 95% CI: 0.347, 0.959) were less likely to have late menopause. BMIs between 25 and 30 (OR = 1.565, 95% CI: 1.152, 2.125) and greater than 30 (OR = 2.440, 95% CI: 1.482, 4.016) were associated with later menopausal age. Late menopause was positively associated with diabetes (OR = 1.611, 95% CI: 1.142, 2.274) but protective against chronic gastroenteritis/peptic ulcers (OR = 0.533, 95% CI: 0.333, 0.855). Results showed that (1) Being born in an earlier year, having a lower education, and engaging in physical labor were associated with an earlier menopausal age, while a higher BMI was associated with a later menopausal age; and that (2) menopausal age was associated with diabetes and gastroenteritis in elderly women living in Northeast China. PMID:27669270

  20. Emergency surgical admissions in patients aged more than 80 years: a study over four decades.

    PubMed Central

    Menon, K. V.; Young, F. M.; Galland, R. B.

    2000-01-01

    BACKGROUND: The proportion of older patients in the community is rising. The aim of this study was to determine the trend in emergency surgical admissions in patients over 80 years of age in 1997 compared with the previous three decades. PATIENTS AND METHODS: Data were obtained on all patients over 80 years of age admitted as general surgical emergencies in 1997 to the Royal Berkshire and Battle Hospitals, Reading, UK. Reasons for admission, management, mortality and duration of hospital stay were recorded and compared with results from 1966, 1976 and 1989. RESULTS: During 1997, 4807 patients over the age of 80 years were admitted as emergencies to all specialities. Of these, 447 (9.3%) were surgical. This compares with 122 in 1966, 248 in 1976 and 339 in 1989. Emergency surgical workload in patients over 80 years of age had increased from 6.2% in 1966 to 12% in 1997. A random sample of 261 patients was analysed. In-patient mortality was 13.8% in 1997 compared with 21.8% for 1976 and 22.4% for 1989. Median length of stay was 8 days (range, 0-41 days) for 1997 and 1989 compared with 14 days in 1976. Twenty-four patients either needed admission to other specialities or need not have been admitted as emergencies at all and were classified as inappropriate admissions to the general surgical ward. CONCLUSIONS: The trend of increased number of patients over the age of 80 years being admitted as emergencies to general surgery continues through four decades. There has been a decrease in mortality and length of stay since 1966, but no decrease in length of stay in 1997 compared with 1989. Avoiding inappropriate admissions would result in a significant improvement in bed utilisation for elective surgery and help to reduce waiting lists. PMID:11103155

  1. The Vanderbilt Memory & Aging Project: Study Design and Baseline Cohort Overview

    PubMed Central

    Jefferson, Angela L.; Gifford, Katherine A.; Acosta, Lealani Mae Y.; Bell, Susan P.; Donahue, Manus J.; Davis, L. Taylor; Gottlieb, JoAnn; Gupta, Deepak K.; Hohman, Timothy J.; Lane, Elizabeth M.; Libon, David J.; Mendes, Lisa A.; Niswender, Kevin; Pechman, Kimberly R.; Rane, Swati; Ruberg, Frederick L.; Su, Yan Ru; Zetterberg, Henrik; Liu, Dandan

    2016-01-01

    Background Vascular health factors frequently co-occur with Alzheimer’s disease (AD). A better understanding of how systemic vascular and cerebrovascular health intersects with clinical and pathological AD may inform prevention and treatment opportunities. Objective To establish the Vanderbilt Memory & Aging Project, a case-control longitudinal study investigating vascular health and brain aging, and describe baseline methodology and participant characteristics. Methods From September 2012 to November 2014, 335 participants age 60–92 were enrolled, including 168 individuals with mild cognitive impairment (MCI, 73 ± 8 years, 41% female) and 167 age-, sex-, and race-matched cognitively normal controls (NC, 72 ± 7 years, 41% female). At baseline, participants completed a physical and frailty examination, fasting blood draw, neuropsychological assessment, echocardiogram, cardiac MRI, and brain MRI. A subset underwent 24-hour ambulatory blood pressure monitoring and lumbar puncture for cerebrospinal fluid (CSF) collection. Results As designed, participant groups were comparable for age (p = 0.31), sex (p = 0.95), and race (p = 0.65). MCI participants had greater Framingham Stroke Risk Profile scores (p = 0.008), systolic blood pressure values (p = 0.008), and history of left ventricular hypertrophy (p = 0.04) than NC participants. As expected, MCI participants performed worse on all neuropsychological measures (p-values<0.001), were more likely to be APOE ε4 carriers (p = 0.02), and had enhanced CSF biomarkers, including lower Aβ42 (p = 0.02), higher total tau (p = 0.004), and higher p-tau (p = 0.02) compared to NC participants. Conclusion Diverse sources of baseline and longitudinal data will provide rich opportunities to investigate pathways linking vascular and cerebrovascular health, clinical and pathological AD, and neurodegeneration contributing to novel strategies to delay or prevent cognitive decline. PMID:26967211

  2. Age and gender leucocytes variances and references values generated using the standardized ONE-Study protocol.

    PubMed

    Kverneland, Anders H; Streitz, Mathias; Geissler, Edward; Hutchinson, James; Vogt, Katrin; Boës, David; Niemann, Nadja; Pedersen, Anders Elm; Schlickeiser, Stephan; Sawitzki, Birgit

    2016-06-01

    Flow cytometry is now accepted as an ideal technology to reveal changes in immune cell composition and function. However, it is also an error-prone and variable technology, which makes it difficult to reproduce findings across laboratories. We have recently developed a strategy to standardize whole blood flow cytometry. The performance of our protocols was challenged here by profiling samples from healthy volunteers to reveal age- and gender-dependent differences and to establish a standardized reference cohort for use in clinical trials. Whole blood samples from two different cohorts were analyzed (first cohort: n = 52, second cohort: n = 46, both 20-84 years with equal gender distribution). The second cohort was run as a validation cohort by a different operator. The "ONE Study" panels were applied to analyze expression of >30 different surface markers to enumerate proportional and absolute numbers of >50 leucocyte subsets. Indeed, analysis of the first cohort revealed significant age-dependent changes in subsets e.g. increased activated and differentiated CD4(+) and CD8(+) T cell subsets, acquisition of a memory phenotype for Tregs as well as decreased MDC2 and Marginal Zone B cells. Males and females showed different dynamics in age-dependent T cell activation and differentiation, indicating faster immunosenescence in males. Importantly, although both cohorts consisted of a small sample size, our standardized approach enabled validation of age-dependent changes with the second cohort. Thus, we have proven the utility of our strategy and generated reproducible reference ranges accounting for age- and gender-dependent differences, which are crucial for a better patient monitoring and individualized therapy. © 2016 International Society for Advancement of Cytometry. PMID:27144459

  3. [Histological and histochemical studies on mouthpart of Whitmania pigra at different months age].

    PubMed

    Liu, Hong; Guo, Qiao-Sheng; Shi, Hong-Zhuan; Wang, Jia; Li, Yan-Xian

    2014-06-01

    Mouthpart developmental histology of Whitmania pigra at different month of age were studied by paraffin section, HE staining combined alcian blue and periodic acid schifts reaction procedure (AB-PAS). The following results was obtained: Change ranges: oral width 0.6 mm (1-3 month), 1.2 mm (34 month); oral diameter 0.3 mm (1-3 month); 1.2 mm (34 month), the oral size reached maximum during 4-6 months and unchanged thereafter. Oral lip had a thin protective film located in the front of the mouthpart. The W. pigra possessed three jaws in oral cavity, the big one was in dorsum, the other two separated on both side of abdomen respectively. Jaws and muscular pharynx were interrelated closely. The jaws were composed by cuticle, epithelial layer, muscularis and jaw cavity from outside to inside. In the front of jaws had mastoid abdomen with function of secreting acidophilic granule from 2 month age. Oral cavity was composed by mucosa, submucosa and muscularis inside and outside. Oral cavity was rich of peristomial nerves. And pharynx was composed of mucosa, muscularis, adventitia from inside to outside. The folds height and width become heighten and thicken. Mucosa epithelium from complex flat epithelium changed into columnar epithelium, muscularis gradually developed into thickened along with growing. Muscular thickness reached maximum at 4 months. Mucous cells of W. pigra were classified into I-IV types based on different staining and two mainly morphological shapes (Tubular, Pear-shaped). Jaws, oral cavity, pharynx by AB-PAS staining showed little changes at different month of age. Mucous cells were few at 1 month age, and type II cells were increased rapidly in 2-3 month age in oral lip. Oral cavity contains more mucous gland cells type I. Under the muscularis there were connective tissues which distributed a few of mucous cells type II. PMID:25244755

  4. Color vision deficiency in a middle-aged population: the Shahroud Eye Study.

    PubMed

    Jafarzadehpur, Ebrahim; Hashemi, Hassan; Emamian, Mohammad Hassan; Khabazkhoob, Mehdi; Mehravaran, Shiva; Shariati, Mohammad; Fotouhi, Akbar

    2014-10-01

    The aim of this study was to determine the prevalence of color vision defects in the middle-age population of Shahroud, Iran. We selected 6,311 people from the 40- to 64-year-old population through random cluster sampling. Color vision testing was performed with the Farnsworth D-15. Cases with similar and symmetric results in both eyes were classified as hereditary, and those with asymmetric results were considered acquired. Cases that did not conform to standard patterns were classified as unknown category. Of 5,190 respondents (response rate 82.2 %), 5,102 participants underwent the color vision test. Of these, 14.7 % (95 % confidence interval 13.7-15.6) had some type of color vision deficiency. Of the 2,157 male participants, 6.2 % were hereditary and 10.2 % were acquired and of the 2,945 female participants, 3.1 % were hereditary and 10 % were acquired. Hereditary color deficiencies were mostly of the deutan form (63.8 %), and acquired deficiencies were mostly tritan (66.1 %). The prevalence of hereditary and acquired color vision deficiency, as well as different types of red-green and blue-yellow color vision defects significantly increased with age (p < 0.001). In conclusion, the pattern of color vision defects among the middle-aged population of Shahroud was significantly different from that seen in the younger population. This could be due to changes associated with age, gender, medical and ocular conditions, and differences in race and environment. Thus, results of previous examinations and the overall health status should be considered before making any judgment about the status of color vision in middle-aged people.

  5. Fetal antiepileptic drug exposure and cognitive outcomes at age 6 years (NEAD study): a prospective observational study

    PubMed Central

    Meador, Kimford J; Baker, Gus A; Browning, Nancy; Cohen, Morris J; Bromley, Rebecca L; Clayton-Smith, Jill; Kalayjian, Laura A; Kanner, Andres; Liporace, Joyce D; Pennell, Page B; Privitera, Michael; Loring, David W

    2013-01-01

    Summary Background Many women of childbearing potential take antiepileptic drugs, but the cognitive effects of fetal exposure are uncertain. We aimed to assess effects of commonly used antiepileptic drugs on cognitive outcomes in children up to 6 years of age. Methods In this prospective, observational, assessor-masked, multicentre study, we enrolled pregnant women with epilepsy on antiepileptic drug monotherapy (carbamazepine, lamotrigine, phenytoin, or valproate) between October, 1999, and February, 2004, at 25 epilepsy centres in the UK and the USA. Our primary outcome was intelligence quotient (IQ) at 6 years of age (age-6 IQ) in all children, assessed with linear regression adjusted for maternal IQ, antiepileptic drug type, standardised dose, gestational birth age, and use of periconceptional folate. We also assessed multiple cognitive domains and compared findings with outcomes at younger ages. This study is registered with ClinicalTrials.gov, number NCT00021866. Findings We included 305 mothers and 311 children (six twin pairs) in the primary analysis. 224 children completed 6 years of follow-up (6-year-completer sample). Multivariate analysis of all children showed that age-6 IQ was lower after exposure to valproate (mean 97, 95% CI 94–101) than to carbamazepine (105, 102–108; p=0·0015), lamotrigine (108, 105–110; p=0·0003), or phenytoin (108, 104–112; p=0·0006). Children exposed to valproate did poorly on measures of verbal and memory abilities compared with those exposed to the other antiepileptic drugs and on non-verbal and executive functions compared with lamotrigine (but not carbamazepine or phenytoin). High doses of valproate were negatively associated with IQ (r=−0·56, p<0·0001), verbal ability (r=−0·40, p=0·0045), non-verbal ability (r=−0·42, p=0·0028), memory (r=−0·30, p=0·0434), and executive function (r=−0·42, p=0·0004), but other antiepileptic drugs were not. Age-6 IQ correlated with IQs at younger ages, and IQ

  6. Sex, age, race and intervention type in clinical studies of HIV cure: a systematic review.

    PubMed

    Johnston, Rowena E; Heitzeg, Mary M

    2015-01-01

    This systematic review was undertaken to determine the extent to which adult subjects representing sex (female), race (nonwhite), and age (>50 years) categories are included in clinical studies of HIV curative interventions and thus, by extension, the potential for data to be analyzed that may shed light on the influence of such demographic variables on safety and/or efficacy. English-language publications retrieved from PubMed and from references of retrieved papers describing clinical studies of curative interventions were read and demographic, recruitment year, and intervention-type details were noted. Variables of interest included participation by sex, age, and race; changes in participation rates by recruitment year; and differences in participation by intervention type. Of 151 publications, 23% reported full demographic data of study enrollees, and only 6% reported conducting efficacy analyses by demographic variables. Included studies recruited participants from 1991 to 2011. No study conducted safety analyses by demographic variables. The representation of women, older people, and nonwhites did not reflect national or international burdens of HIV infection. Participation of demographic subgroups differed by intervention type and study location. Rates of participation of demographic groups of interest did not vary with time. Limited data suggest efficacy, particularly of early therapy initiation followed by treatment interruption, may vary by demographic variables, in this case sex. More data are needed to determine associations between demographic characteristics and safety/efficacy of curative interventions. Studies should be powered to conduct such analyses and cure-relevant measures should be standardized.

  7. Age-related changes in rat cerebellar basket cells: a quantitative study using unbiased stereological methods

    PubMed Central

    HENRIQUE, RUI M. F.; ROCHA, EDUARDO; REIS, ALCINDA; MARCOS, RICARDO; OLIVEIRA, MARIA H.; SILVA, MARIA W.; MONTEIRO, ROGÉRIO A. F.

    2001-01-01

    Cortical cerebellar basket cells are stable postmitotic cells; hence, they are liable to endure age-related changes. Since the cerebellum is a vital organ for the postural control, equilibrium and motor coordination, we aimed to determine the quantitative morphological changes in those interneurons with the ageing process, using unbiased techniques. Material from the cerebellar cortex (Crus I and Crus II) was collected from female rats aged 2, 6, 9, 12, 15, 18, 21 and 24 mo (5 animals per each age group), fixed by intracardiac perfusion, and processed for transmission electron microscopy, using conventional techniques. Serial semithin sections were obtained (5 blocks from each rat), enabling the determination of the number-weighted mean nuclear volume (by the nucleator method). On ultrathin sections, 25 cell profiles from each animal were photographed. The volume density of the nucleus, ground substance, mitochondria, Golgi apparatus (Golgi) and dense bodies (DB), and the mean surface density of the rough endoplasmic reticulum (RER) were determined, by point counting, using a morphometric grid. The mean total volumes of the soma and organelles and the mean total surface area of the RER [s̄N (RER)] were then calculated. The results were analysed with 1-way ANOVA; posthoc pairwise comparisons of group means were performed using the Newman-Keuls test. The relation between age and each of the parameters was studied by regression analysis. Significant age-related changes were observed for the mean volumes of the soma, ground substance, Golgi, DB, and s̄N (RER). Positive linear trends were found for the mean volumes of the ground substance, Golgi, and DB; a negative linear trend was found for the s̄N (RER). These results indicate that rat cerebellar basket cells endure important age-related changes. The significant decrease in the s̄N (RER) may be responsible for a reduction in the rate of protein synthesis. Additionally, it may be implicated in a cascade of events

  8. [Aging Process of Puer Black Tea Studied by FTIR Spectroscopy Combined with Curve-Fitting Analysis].

    PubMed

    Li, Dong-yu; Shi, You-ming; Yi, Shi Lai

    2015-07-01

    aging time. The present study suggested that Fourier transform infrared spectroscopy combined with curve-fitting analysis could reveal the biochemical changed of Puer black tea with the increase of aging time, and it was evidence for evaluation the quality of Puer black tea.

  9. Study on long-term irradiation aging of electrical cables (The VEILLE program)

    SciTech Connect

    Carlin, F.; Attal, M.; Gaussens, G.

    1995-04-01

    The VEILLE program (French acronym for study on long-term irradiation aging of electrical cables) was implemented in 1988 by the Institute of Protection and Nuclear Safety (IPSN) in collaboration with the US Nuclear Regulatory Commission (NRC) for a period of six years. It is intended to validate the assumptions put forward as regards aging of electrical cables and to develop criteria for early detection of degradation likely to lead to functional failures. The tests were carried out partly at the Sandia National Laboratories in the United States, partly in France in the CIS bio international Laboratories at the Saclay Nuclear Research Centre. The study focused on the radiation effects from cobalt 60 on electrical cables made up of various polymers for two temperatures and at various dose rates. Other tests were also performed using a device laid under water in the OSIRIS reactor pool at Saclay to test cables under irradiation and temperature conditions close to those found in nuclear power plant operation. Subsequently the aged cables were subjected to containment accident conditions (irradiation and thermodynamic profile) in order to show any degradation due to aging. The study showed the significant effect of radiation doses on EPR and EPDM cable insulations as well as synergy between radiation dose rates and temperature on the mechanical properties of the Hypalon sheath. Correlation between the mechanical properties and the function of cables is difficult to establish as electrical characteristics are preserved whatever the type of mechanical degradation observed. Finally, the performance of electrical cables after an accident remains a key criterion to define the materials likely to be used when manufacturing cables intended to ensure safety functions.

  10. Association Between Visuospatial Ability and Vestibular Function in the Baltimore Longitudinal Study of Aging

    PubMed Central

    Bigelow, Robin T.; Semenov, Yevgeniy R.; Trevino, Carolina; Ferrucci, Luigi; Resnick, Susan M.; Simonsick, Eleanor M.; Xue, Qian-Li; Agrawal, Yuri

    2016-01-01

    OBJECTIVES To investigate the relationship between vestibular loss associated with aging and age-related decline in visuospatial function. DESIGN Cross-sectional analysis within a prospective cohort study. SETTING Baltimore Longitudinal Study of Aging (BLSA). PARTICIPANTS Community-dwelling BLSA participants with a mean age of 72 (range 26–91) (N = 183). MEASUREMENTS Vestibular function was measured using vestibular-evoked myogenic potentials. Visuospatial cognitive tests included Card Rotations, Purdue Pegboard, Benton Visual Retention Test, and Trail-Making Test Parts A and B. Tests of executive function, memory, and attention were also considered. RESULTS Participants underwent vestibular and cognitive function testing. In multiple linear regression analyses, poorer vestibular function was associated with poorer performance on Card Rotations (P = .001), Purdue Pegboard (P = .005), Benton Visual Retention Test (P = 0.008), and Trail-Making Test Part B (P = .04). Performance on tests of executive function and verbal memory were not significantly associated with vestibular function. Exploratory factor analyses in a subgroup of participants who underwent all cognitive tests identified three latent cognitive abilities: visuospatial ability, verbal memory, and working memory and attention. Vestibular loss was significantly associated with lower visuospatial and working memory and attention factor scores. CONCLUSION Significant consistent associations between vestibular function and tests of visuospatial ability were observed in a sample of community-dwelling adults. Impairment in visuospatial skills is often one of the first signs of dementia and Alzheimer’s disease. Further longitudinal studies are needed to evaluate whether the relationship between vestibular function and visuospatial ability is causal. PMID:26311169

  11. Impaired Sleep Predicts Cognitive Decline in Old People: Findings from the Prospective KORA Age Study

    PubMed Central

    Johar, Hamimatunnisa; Kawan, Rasmila; Emeny, Rebecca Thwing; Ladwig, Karl-Heinz

    2016-01-01

    Study Objectives: To investigate the association between sleep-related characteristics and cognitive change over 3 years of follow up in an aged population. Methods: Sleep characteristics and covariates were assessed at baseline in a standardized interview and clinical examination of the population-based KORA Age Study (n = 740, mean age = 75 years). Cognitive score (determined by telephone interview for cognitive status, TICS-m) was recorded at baseline and 3 years later. Results: At baseline, 82.83% (n = 613) of participants had normal cognitive status, 13.51% (n = 100) were classified with mild cognitive impairment (MCI), and 3.64% (n = 27) with probable dementia. The effect of three distinct patterns of poor sleep (difficulties initiating [DIS] or maintaining sleep [DMS], daytime sleepiness [DS] or sleep duration) were considered on a change in cognitive score with adjustments for potential confounders in generalized linear regression models. Cognitive decline was more pronounced in individuals with DMS compared to those with no DMS (β = 1.33, 95% CI = 0.41–2.24, P < 0.001). However, the predictive power of DMS was only significant in individuals with normal cognition and not impaired subjects at baseline. Prolonged sleep duration increased the risk for cognitive decline in cognitively impaired elderly (β = 1.86, 95% CI = 0.15–3.57, P = 0.03). Other sleep characteristics (DIS and DS) were not significantly associated with cognitive decline. Conclusions: DMS and long sleep duration were associated with cognitive decline in normal and cognitively impaired elderly, respectively. The identification of impaired sleep quality may offer intervention strategies to deter cognitive decline in the elderly with normal cognitive function. Citation: Johar H, Kawan R, Emeny RT, Ladwig KH. Impaired sleep predicts cognitive decline in old people: findings from the prospective KORA age study. SLEEP 2016;39(1):217–226. PMID:26414903

  12. Serum folate, vitamin B-12 and cognitive function in middle and older age: The HAPIEE study

    PubMed Central

    Horvat, Pia; Gardiner, Julian; Kubinova, Ruzena; Pajak, Andrzej; Tamosiunas, Abdonas; Schöttker, Ben; Pikhart, Hynek; Peasey, Anne; Jansen, Eugene; Bobak, Martin

    2016-01-01

    Background Nutrient status of B vitamins, particularly folate and vitamin B-12, may be related to cognitive ageing but epidemiological evidence remains inconclusive. Objective The aim of this study was to estimate the association of serum folate and vitamin B-12 concentrations with cognitive function in middle-aged and older adults from three Central and Eastern European populations. Methods Men and women aged 45–69 at baseline participating in the Health, Alcohol and Psychosocial factors in Eastern Europe (HAPIEE) study were recruited in Krakow (Poland), Kaunas (Lithuania) and six urban centres in the Czech Republic. Tests of immediate and delayed recall, verbal fluency and letter search were administered at baseline and repeated in 2006–2008. Serum concentrations of biomarkers at baseline were measured in a sub-sample of participants. Associations of vitamin quartiles with baseline (n = 4166) and follow-up (n = 2739) cognitive domain-specific z-scores were estimated using multiple linear regression. Results After adjusting for confounders, folate was positively associated with letter search and vitamin B-12 with word recall in cross-sectional analyses. In prospective analyses, participants in the highest quartile of folate had higher verbal fluency (p < 0.01) and immediate recall (p < 0.05) scores compared to those in the bottom quartile. In addition, participants in the highest quartile of vitamin B-12 had significantly higher verbal fluency scores (β = 0.12; 95% CI = 0.02, 0.21). Conclusions Folate and vitamin B-12 were positively associated with performance in some but not all cognitive domains in older Central and Eastern Europeans. These findings do not lend unequivocal support to potential importance of folate and vitamin B-12 status for cognitive function in older age. Long-term longitudinal studies and randomised trials are required before drawing conclusions on the role of these vitamins in cognitive decline. PMID:26808046

  13. Healthy ageing in Isan-Thai culture--A phenomenographic study based on older persons' lived experiences.

    PubMed

    Manasatchakun, Pornpun; Chotiga, Pleumjit; Roxberg, Åsa; Asp, Margareta

    2016-01-01

    Healthy ageing is a concept that concerns older persons' quality of life and is a key factor in promoting well-being. The older population in Thailand is growing. Isan (a region of north-eastern Thailand) has been reported as having one of the most rapidly increasing older populations in the country. In order to care for and promote the health of older people, healthcare providers should understand how healthy ageing is perceived by this target group. Although healthy ageing has been studied in different contexts as well as perspectives, no studies have previously focused on older persons' experiences of healthy ageing from a lifeworld perspective in Isan-Thai. Therefore, the aim of this study is to describe older persons' qualitatively different conceptions of healthy ageing in Isan-Thai culture. A phenomenographic approach with an epistemological base in lifeworld theory was used to disclose the various ways to conceptualize healthy ageing. Individual, qualitative interviews were conducted with 17 people aged 60 and above who live in Isan-Thai. The findings of this study revealed three categories of descriptions: "being independent in dependence," "being at peace," and "being a valuable person." This study also found family members, friends, healthcare providers, and religion important to healthy ageing in the Isan-Thai culture. Understanding how older people conceptualize healthy ageing is valuable for healthcare providers. They can apply these findings regarding healthy ageing in their fieldwork when caring for older people. PMID:26960686

  14. Healthy ageing in Isan-Thai culture--A phenomenographic study based on older persons' lived experiences.

    PubMed

    Manasatchakun, Pornpun; Chotiga, Pleumjit; Roxberg, Åsa; Asp, Margareta

    2016-01-01

    Healthy ageing is a concept that concerns older persons' quality of life and is a key factor in promoting well-being. The older population in Thailand is growing. Isan (a region of north-eastern Thailand) has been reported as having one of the most rapidly increasing older populations in the country. In order to care for and promote the health of older people, healthcare providers should understand how healthy ageing is perceived by this target group. Although healthy ageing has been studied in different contexts as well as perspectives, no studies have previously focused on older persons' experiences of healthy ageing from a lifeworld perspective in Isan-Thai. Therefore, the aim of this study is to describe older persons' qualitatively different conceptions of healthy ageing in Isan-Thai culture. A phenomenographic approach with an epistemological base in lifeworld theory was used to disclose the various ways to conceptualize healthy ageing. Individual, qualitative interviews were conducted with 17 people aged 60 and above who live in Isan-Thai. The findings of this study revealed three categories of descriptions: "being independent in dependence," "being at peace," and "being a valuable person." This study also found family members, friends, healthcare providers, and religion important to healthy ageing in the Isan-Thai culture. Understanding how older people conceptualize healthy ageing is valuable for healthcare providers. They can apply these findings regarding healthy ageing in their fieldwork when caring for older people.

  15. Participation and social networks of school-age children with complex communication needs: a descriptive study.

    PubMed

    Thirumanickam, Abirami; Raghavendra, Parimala; Olsson, Catherine

    2011-09-01

    Social participation becomes particularly important in middle childhood, as it contributes towards the acquisition and development of critical life skills such as developing friendships and a sense of belonging. However, only limited literature is available on the impact of communication difficulties on social participation in middle childhood. This study compared the participation patterns of school-age children with and without physical disabilities and complex communication needs in extracurricular activities. Participants included five children between 6-9 years of age with moderate-severe physical disability and complex communication needs, and five matched peers. Findings showed that children with physical disability and complex communication needs engaged in activities with reduced variety, lower frequency, fewer partners and in limited venues, but reported higher levels of enjoyment and preference for activity participation, than their matched peers. These children also had fewer same-aged friends, but more paid workers in their social circle. This small-scale descriptive study provides some preliminary evidence about the impact of severe communication difficulties on participation and socialization. PMID:22008032

  16. Life at Age 100: An International Research Agenda for Centenarian Studies.

    PubMed

    Jopp, Daniela S; Boerner, Kathrin; Ribeiro, Oscar; Rott, Christoph

    2016-01-01

    Living a long life is desired by many individuals, and this dream is likely to become reality in more and more industrialized societies. During the past 3 decades, the number of very old individuals has increased significantly, creating a global demographic challenge with consequences at the individual, family, and societal levels. Yet, life in very old age is still poorly understood in terms of its unique characteristics and challenges. Besides specific content areas, very old age represents an understudied field of research. This lack of knowledge may be one reason that the very old also are an underserved population. This special issue introduces an international network of three centenarian studies that describe and compare the life circumstances and characteristics of centenarians across Germany, Portugal, and the United States. Our parallel studies comprehensively assess centenarians' physical, cognitive, social, and psychological functioning to create a knowledge base regarding their capacities and needs. A specific focus lies in the investigation of psychological aspects, social resources, and societal/cultural contexts, factors that may contribute to longevity and successful aging. Determining key characteristics of this very old population and investigating similarities and differences across countries is timely and urgent, both from an applied and a policy standpoint. PMID:26984376

  17. Neurovascular coupling in normal aging: A combined optical, ERP and fMRI study

    PubMed Central

    Fabiani, Monica; Gordon, Brian A.; Maclin, Edward L.; Pearson, Melanie A.; Brumback-Peltz, Carrie R.; Low, Kathy A.; McAuley, Edward; Sutton, Bradley P.; Kramer, Arthur F.; Gratton, Gabriele

    2013-01-01

    Brain aging is characterized by changes in both hemodynamic and neuronal responses, which may be influenced by the cardiorespiratory fitness of the individual. To investigate the relationship between neuronal and hemodynamic changes, we studied the brain activity elicited by visual stimulation (checkerboard reversals at different frequencies) in younger adults and in older adults varying in physical fitness. Four functional brain measures were used to compare neuronal and hemodynamic responses obtained from BA17: two reflecting neuronal activity (the event-related optical signal, EROS, and the C1 response of the ERP), and two reflecting functional hemodynamic changes (functional magnetic resonance imaging, fMRI, and near-infrared spectroscopy, NIRS). The results indicated that both younger and older adults exhibited a quadratic relationship between neuronal and hemodynamic effects, with reduced increases of the hemodynamic response at high levels of neuronal activity. Although older adults showed reduced activation, similar neurovascular coupling functions were observed in the two age groups when fMRI and deoxy-hemoglobin measures were used. However, the coupling between oxy-and deoxy-hemoglobin changes decreased with age and increased with increasing fitness. These data indicate that departures from linearity in neurovascular coupling may be present when using hemodynamic measures to study neuronal function. PMID:23664952

  18. A study of gender, strain and age differences in mouse liver glutathione-S-transferase.

    PubMed

    Egaas, E; Falls, J G; Dauterman, W C

    1995-01-01

    The hepatic cytosolic glutathione S-transferase (GST) activity in four strains of the mouse and one strain of the rat was studied with the substrates 1-chloro-2,4-dinitrobenzene (CDNB), 1,2-dichloro-4-nitrobenzene (DCNB), ethachrynic acid (ETHA), cumene hydroperoxide (CU) and atrazine as the in vitro substrates. In the mouse, significant gender, strain and age-related differences in the GST activity towards CDNB and atrazine were found between adolescent and sexually mature males and females of the CD-1, C57BL/6, DBA/2 and Swiss-Webster strains, and the differences were larger with atrazine as the substrate. With DCNB and CU a similar tendency was observed, however not significant for all strains. The GST activity towards ETHA was also gender and strain specific, but revealed no age-related differences. The herbicide atrazine seems to be a useful substrate in the study of strain and age-related differences in the mouse GST class Pi.

  19. Relationship between Metabolic Syndrome and Lower Urinary Tract Symptoms: Hallym Aging Study

    PubMed Central

    Lee, Seong Ho; Lee, Sang Kon; Choo, Min Soo; Ko, Kyung Tae; Shin, Tae Young; Lee, Won Ki; Batsaikhan, Tsolmon; Quan, ShanAi; Jeong, Jin Young; Kim, Dong Hyun

    2015-01-01

    The aim of the study was to test the hypothesis that the metabolic syndrome (MS) is linked to lower urinary tract symptoms (LUTS) in Korean men. This was a longitudinal study that used data collected from 328 men aged 50–89 years who were randomly selected among 1,520 participants in 2004. We collected information from 224 (68.3%) men among the original responders on the biological, medical, psychological, social, lifestyle, and economic factors in 2007. The prevalence of the MS was 187/328 (57.0%) in 2004 and 125/224 (55.8%) in 2007 among men, respectively. There was no significantly greater increase in the IPSS in men with the MS than in men without the MS over a 3-year period of time (2.0 ± 9.37 versus 3.0 ± 8.44, p = 0.402, resp.). In the multivariate logistic regression analysis with control for age and life style factors, the risk factors for moderate/severe LUTS were age and erectile dysfunction (p < 0.05). However, the presence of the MS did not increase the risk of moderate/severe LUTS (OR = 1.09, 95% CI 0.63–1.89, p = 0.748). Our cross-sectional and longitudinal risk factor analyses do not support the hypothesis that the MS is linked to LUTS in Korean men. PMID:26199934

  20. Relationship between Metabolic Syndrome and Lower Urinary Tract Symptoms: Hallym Aging Study.

    PubMed

    Lee, Seong Ho; Lee, Sang Kon; Choo, Min Soo; Ko, Kyung Tae; Shin, Tae Young; Lee, Won Ki; Batsaikhan, Tsolmon; Quan, ShanAi; Jeong, Jin Young; Kim, Dong Hyun

    2015-01-01

    The aim of the study was to test the hypothesis that the metabolic syndrome (MS) is linked to lower urinary tract symptoms (LUTS) in Korean men. This was a longitudinal study that used data collected from 328 men aged 50-89 years who were randomly selected among 1,520 participants in 2004. We collected information from 224 (68.3%) men among the original responders on the biological, medical, psychological, social, lifestyle, and economic factors in 2007. The prevalence of the MS was 187/328 (57.0%) in 2004 and 125/224 (55.8%) in 2007 among men, respectively. There was no significantly greater increase in the IPSS in men with the MS than in men without the MS over a 3-year period of time (2.0 ± 9.37 versus 3.0 ± 8.44, p = 0.402, resp.). In the multivariate logistic regression analysis with control for age and life style factors, the risk factors for moderate/severe LUTS were age and erectile dysfunction (p < 0.05). However, the presence of the MS did not increase the risk of moderate/severe LUTS (OR = 1.09, 95% CI 0.63-1.89, p = 0.748). Our cross-sectional and longitudinal risk factor analyses do not support the hypothesis that the MS is linked to LUTS in Korean men. PMID:26199934