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Sample records for aging study nas

  1. Experimental studies on atmospheric Stirling engine NAS-2

    SciTech Connect

    Watanabe, Hiroichi; Isshiki, Naotsugu; Ohtomo, Michihiro

    1996-12-31

    Atmospheric hot air Stirling engine NAS-1 and 2 have a simple flat rubber sheet diaphragm as their power piston, and they have been experimentally studied at Nihon University for several years continuously, with the target of to get more than 100 watts shaft power by atmospheric air with simple construction and cheap material. The first NAS-1 was intended to be a solar heated engine using television glass and wood for cheap cost, but it failed by thermal break of glass, so the improved NAS-2 is changed to be heated by gas burner, using metallic materials in all parts except rubber power piston. Other than this rubber sheet diaphragm, NAS-2 has many features as using James Watt crank mechanism, high finny copper tube for conventional commercial heat exchanger, and two kinds of hot gas heaters, etc. About the rubber sheet for the power piston, the thickness of the sheet was changed from 2 mm to 6 mm gradually to known what thickness is best, and it is found that about 5 mm is best for this engine. After trying many improvements on this engine, NAS-2 has produced about 130 watt shaft power with indicated power of 350 watt at 1994. In this paper detail of many features, history, results and experiments of these NAS engines are reported.

  2. Study of GaInNAs Epilayers Using Optical Methods

    NASA Astrophysics Data System (ADS)

    Tsai, Yutsung

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

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

    DOE PAGESBeta

    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. Fireset materials aging study

    SciTech Connect

    Smith, H.M.; Arnold, C.; Bailey, M.E.

    1982-07-01

    A thermally-accelerated aging study of 10 selected organic materials used in a fireset has been conducted. The study included both quantitative and qualitative gas analyses as well as the measurement of physical properties before and after accelerated aging. The test plan involved single material aging, as well as pairs and larger groups to look for synergistic interactions. The material types tested were epoxies, polyurethanes, polysulfides, silicones, phenolics, polyolefins, and diallyl phthalates. Only two of the materials tested showed evidence of degradation as a result of aging.

  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. Menopause Hastens Aging, Studies Suggest

    MedlinePlus

    ... gov/news/fullstory_160079.html Menopause Hastens Aging, Studies Suggest Researchers found it boosted cellular aging by ... it, can speed aging in women, two new studies suggest. "For decades, scientists have disagreed over whether ...

  8. 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.

  9. [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

  10. National Academy of Sciences (NAS) Study entitled The Effect of Climate Change on Indoor Air Quality and Public Health.

    EPA Science Inventory

    The Institute of Medicine of the NAS is conducting a study to evaluate the state of scientific understanding of the effects of climate change on indoor air quality and public health. General topics may include the likely impacts of climate change in the U.S. on the indoor environ...

  11. 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.

  12. 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

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

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

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

  14. LONGITUDINAL STUDY OF AGING (LSOA)

    EPA Science Inventory

    The Longitudinal Study of Aging (LSOA) is a collaborative effort of the National Center for Health Statistics (NCHS) and the National Institute on Aging (NIA). The Supplement on Aging (SOA), conducted in conjunction with the 1984 National Health Interview Survey (NHIS), served as...

  15. NATIONAL ALCOHOL SURVEY (NAS)

    EPA Science Inventory

    National Alcohol Survey (NAS) is designed to assess the trends in drinking practices and problems in the national population, including attitudes, norms, treatment and experiences and adverse consequences. It also studies the effects of public policy on drinking practices (i.e., ...

  16. 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

  17. The NAS Computational Aerosciences Archive

    NASA Technical Reports Server (NTRS)

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

    1995-01-01

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

  18. 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. NAS: The first year

    NASA Technical Reports Server (NTRS)

    Bailey, F. R.; Kutler, Paul

    1988-01-01

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

  20. 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.

  1. 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.

  2. Study of nitrogen incorporation into GaInNAs: The role of growth temperature in molecular beam epitaxy

    SciTech Connect

    Korpijaervi, V.-M.; Aho, A.; Tukiainen, A.; Laakso, A.; Guina, M.; Laukkanen, P.; Tuominen, M.

    2012-07-15

    GaInNAs has an important impact on developing GaAs-based optoelectronics and multijunction solar cells, but the complex nature of the nitrogen incorporation into GaInAs is still not fully understood. By combining x-ray diffraction, photoluminescence, reflection high-energy electron diffraction, and photoelectron spectroscopy measurements, we show that nitrogen incorporation is enhanced with increasing growth temperature in the range of 300-450 Degree-Sign C. We study the growth front and show that the surface reconstruction is (1 Multiplication-Sign 3) regardless of growth temperature in this range. The enhanced nitrogen incorporation can be modeled as a thermally activated process with activation energy of about 0.1 eV.

  3. 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

  4. Aging Studies in Drosophila melanogaster

    PubMed Central

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

    2015-01-01

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

  5. The NAS 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

  6. NAS Parallel Benchmarks Results

    NASA Technical Reports Server (NTRS)

    Subhash, Saini; Bailey, David H.; Lasinski, T. A. (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 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. In this paper, we present new NPB performance results for the following systems: (a) Parallel-Vector Processors: Cray C90, Cray T'90 and Fujitsu VPP500; (b) Highly Parallel Processors: Cray T3D, IBM SP2 and IBM SP-TN2 (Thin Nodes 2); (c) Symmetric Multiprocessing Processors: Convex Exemplar SPP1000, Cray J90, DEC Alpha Server 8400 5/300, and SGI Power Challenge XL. We also present sustained performance per dollar for Class B LU, SP and BT benchmarks. We also mention NAS future plans of NPB.

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

    NASA Technical Reports Server (NTRS)

    Glaab, Patricia C.

    2011-01-01

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

  8. The Canadian longitudinal study on aging (CLSA).

    PubMed

    Raina, Parminder S; Wolfson, Christina; Kirkland, Susan A; Griffith, Lauren E; Oremus, Mark; Patterson, Christopher; Tuokko, Holly; Penning, Margaret; Balion, Cynthia M; Hogan, David; Wister, Andrew; Payette, Hélène; Shannon, Harry; Brazil, Kevin

    2009-09-01

    ABSTRACTCanadians are living longer, and older persons are making up a larger share of the population (14% in 2006, projected to rise to 20% by 2021). The Canadian Longitudinal Study on Aging (CLSA) is a national longitudinal study of adult development and aging that will recruit 50,000 Canadians aged 45 to 85 years of age and follow them for at least 20 years. All participants will provide a common set of information concerning many aspects of health and aging, and 30,000 will undergo an additional in-depth examination coupled with the donation of biological specimens (blood and urine). The CLSA will become a rich data source for the study of the complex interrelationship among the biological, physical, psychosocial, and societal factors that affect healthy aging. PMID:19860977

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

    PubMed Central

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

    2015-01-01

    In this study, new and feasible UV-visible spectrophotometric and multivariate spectrophotometric methods were described for the simultaneous determination of hydrochlorothiazide (HCTZ), hydralazine hydrochloride (H.HCl), and reserpine (RES) in combined pharmaceutical tablets. Methanol was used as a solvent for analysis and the whole UV region was scanned from 200–400 nm. The resolution was obtained by using multivariate methods such as the net analyte signal method (NAS), principal component analysis (PCA), and net analyte signal-principal component analysis (NAS-PCA) applied to the UV spectra of the mixture. The results obtained from all of the three methods were compared. NAS-PCA showed a lot of resolved data as compared to NAS and PCA. Thus, the NAS-PCA technique is a combination of NAS and PCA methods which is advantageous to obtain the information from overlapping results. PMID:26839841

  10. 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.

  11. 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…

  12. New NAS journal

    NASA Astrophysics Data System (ADS)

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

  13. Numerical Aerodynamic Simulation (NAS)

    NASA Technical Reports Server (NTRS)

    Peterson, V. L.; Ballhaus, W. F., Jr.; Bailey, F. R.

    1983-01-01

    The history of the Numerical Aerodynamic Simulation Program, which is designed to provide a leading-edge capability to computational aerodynamicists, is traced back to its origin in 1975. Factors motivating its development and examples of solutions to successively refined forms of the governing equations are presented. The NAS Processing System Network and each of its eight subsystems are described in terms of function and initial performance goals. A proposed usage allocation policy is discussed and some initial problems being readied for solution on the NAS system are identified.

  14. [Aging of the aorta: a morphological study].

    PubMed

    Pentimone, F; Del Corso, L; Meola, M; Giuliano, G; Borelli, A; Riccioni, S

    1994-05-01

    Aim of this study was to evaluate the aging of aorta with respect to atherosclerotic modifications: abdominal aorta echotomography is the preferred approach for this study. In 354 elderly patients, 65 and over, we have evaluated the diameter and the course of the aorta, the presence of atherosclerotic plaques in the aorta and iliac vessels, and the presence of aneurysms. Two kinds of findings could be identified by echotomography: age-related physiologic modifications, represented essentially by an increase of the aortic diameter; pathologic changes, characteristic for atherosclerosis, of which aneurysms are the most dangerous complications. PMID:7924179

  15. Chicago Healthy Aging Study: Objectives and Design

    PubMed Central

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

    2013-01-01

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

  16. Dynamics of time-resolved photoluminescence in GaInNAs and GaNAsSb solar cells

    PubMed Central

    2014-01-01

    We report a time-resolved photoluminescence study for GaInNAs and GaNAsSb p-i-n bulk solar cells grown on GaAs(100). In particular, we studied the extent to which the carrier lifetime decreases with the increase of N content. Rapid thermal annealing proved to significantly increase the decay times by a factor of 10 to 12 times, for both GaInNAs and GaNAsSb heterostructures, while for the 1-eV bandgap GaNAsSb structure, grown at the same growth conditions as the GaInNAs, the photoluminescence decay time remained slightly below 100 ps after annealing; the approximately 1.15-eV GaInNAs p-i-n solar cell exhibited a lifetime as long as 900 ps. PACS 78.47.D; 78.55.Cr; 88.40.hj PMID:24533702

  17. Aging in Rett syndrome: a longitudinal study.

    PubMed

    Halbach, N S J; Smeets, E E J; Steinbusch, C; Maaskant, M A; van Waardenburg, D; Curfs, L M G

    2013-09-01

    Little is known about the aging process of people with specific syndromes, like Rett syndrome (RTT). Recognition of the clinical and behavioral characteristics of the adult RTT is needed in order to improve future management of the RTT girl and counseling of parents. In association with the Dutch RTT parent association, a 5-year longitudinal study was carried out. The study population consisted of 53 adult women with a clinical diagnosis of RTT. Postal questionnaires were sent, including demographic features, skills, physical and psychiatric morbidity. At the time of the second measurement seven women had died. In 2012, 80% of the questionnaires (37/46) were returned. Mean age of the women was 31.4 years. Molecular confirmation was possible for 83% of the women for whom analyses were carried out. The adult RTT woman has a more or less stable condition. The general disorder profile is that of a slow on-going deterioration of gross motor functioning in contrast to a better preserved cognitive functioning, less autonomic and epileptic features and good general health. This is the first longitudinal cohort study about aging in RTT. Continuing longitudinal studies are needed to gain more insight into the aging process in RTT. PMID:23167724

  18. 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…

  19. XTX8003 Aging Study Status Report

    SciTech Connect

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

    1999-03-08

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

  20. 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

  1. 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.

  2. Aging Studies of VCE Dismantlement Returns

    SciTech Connect

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

    2011-10-17

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

  3. Studies in cutaneous aging: II. The microvasculature

    SciTech Connect

    Braverman, I.M.; Fonferko, E.

    1982-05-01

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

  4. Shippingport aging studies: Results and plans

    SciTech Connect

    Shack, W.J.; Chopra, O.K.; Chung, H.M.

    1988-10-01

    The objective of this program is to develop an understanding of the metallurgical phenomena that may occur in nuclear reactor structural materials as a consequence of extended service at operating temperatures within and outside of the radiation environment and to assess the impact of these phenomena on structural integrity. Although many aging phenomena such as the embrittlement of cast stainless steel, low-temperature sensitization of austenitic stainless steels, and radiation embrittlement of pressure vessel steels have been studied in the laboratory, most of the studies have been based on simulation of actual reactor conditions. The Shippingport reactor offers a unique opportunity to validate and benchmark the laboratory studies, and thereby, provide a sound basis for evaluating the integrity of structural components near the end of the projected life of the plant. Additional work will be undertaken to identify the possibility of new, previously unknown mechanisms of component degradation. 6 refs., 10 figs., 6 tabs.

  5. Binary 193nm photomasks aging phenomenon study

    NASA Astrophysics Data System (ADS)

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

    2011-05-01

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

  6. 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.

  7. Aging.

    PubMed

    Park, Dong Choon; Yeo, Seung Geun

    2013-09-01

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

  8. Aging

    PubMed Central

    Park, Dong Choon

    2013-01-01

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

  9. RNA sequence requirements for NasR-mediated, nitrate-responsive transcription antitermination of the Klebsiella oxytoca M5al nasF operon leader.

    PubMed

    Chai, W; Stewart, V

    1999-09-17

    In Klebsiella oxytoca, enzymes required for nitrate assimilation are encoded by the nasFEDCBA operon. Nitrate and nitrite induction of nasF operon expression is determined by a transcriptional antitermination mechanism, in which the nasR gene product responds to nitrate or nitrite and overcomes transcription termination at the factor-independent terminator site located in the nasF upstream leader region. Previous studies led to the hypothesis that the NasR protein mediates transcription antitermination through interaction with nasF leader RNA. Here, we report a DNA sequence comparison that reveals conserved 1:2 and 3:4 RNA secondary structures in the nasF leader RNAs from two Klebsiella species. Additionally, we found that specific binding of the NasR protein to nasF leader RNA was stimulated by nitrate and nitrite. We combined mutational analysis, in vivo and in vitro antitermination assays, and an RNA electrophoretic mobility shift assay to define regions in the nasF leader that are essential for antitermination and for NasR-RNA interaction. Formation of the 1:2 stem structure and the specific sequence of the 1:2 hexanucleotide loop were required for both nitrate induction and for NasR-RNA interaction. Mutations in the 1:2 stem-loop region that abolished nitrate induction also interfered with NasR-leader RNA interaction. Finally, nucleotide alterations or additions in the linker region between the 1:2 and 3:4 stem-loops were deleterious to nasF operon induction but not to NasR-leader RNA interaction. We hypothesize that NasR protein recognizes the 1:2 stem-loop structure in the nasF leader RNA to mediate transcription antitermination in response to nitrate or nitrite. PMID:10493869

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

    NASA Technical Reports Server (NTRS)

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

    2015-01-01

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

  11. [Wellbeing, health and autonomy in old age: the Basal IDA Study (Interdisciplinary Aging Study)].

    PubMed

    Perrig-Chiello, P; Perrig, W J; Stähelin, H B; Krebs-Roubicek, E; Ehrsam, R

    1996-01-01

    Current research on successful aging reflects a multicriteria approach, although a consensus on the interrelationship between different factors has not yet been achieved. The longitudinal-sequential study presented here aims at identifying psychological, biological and sociobiographical predictors of well-being, health and autonomy in old age and their interdependency. The concern of this study is thus a multidisciplinary approach including psychology, psychiatry, geriatrics and sports sciences. The ongoing study is described and first findings are reported. Four hundred and forty-two people, aged 65 to 94, were tested twice (1993 and 1995). Since this project is a pursuit of a medical longitudinal study (Basler-Studie), bio-medical parameters from former status measurements (1960, 1965, 1971, 1985, 1990) are available and taken into account for comparison with the newly collected data from 1993 and 1995. The tests included both a medical examination and cognitive and personality measurements. The medical test battery included: clinical and anthropometrical data, bio-chemical data as well as the medical history, health behaviour, complaints and subjective health. The psychological assessment included psychological well-being, health-related control beliefs, causal attribution, religiosity, etc. For memory assessment a computerized test was used which allows to test 1) perceptual error-scanning, 2) naming speed, and memory resources in terms of 3) capacity, 4) explicit and 5) implicit components. It therefore integrates direct (free recall, recognition) and indirect memory tests (perceptual identification: clarification), that were used previously in different experimental and quasi-experimental studies to investigate memory performance over the life-span. Furthermore, the following three experimental interventions are performed: memory and reattribution training, physical training and psychoanalytical group therapy. First descriptive results are presented

  12. 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.

  13. Photoluminescence study of InAs quantum dots embedded in GaNAs strain compensating layer grown by metalorganic-molecular-beam epitaxy

    NASA Astrophysics Data System (ADS)

    Zhang, X. Q.; Ganapathy, Sasikala; Kumano, Hidekazu; Uesugi, Kasturi; Suemune, Ikuo

    2002-12-01

    Self-assembled InAs quantum dots (QDs) embedded in GaN0.007As0.993 strain compensating layers have been grown by metalorganic-molecular-beam epitaxy on a GaAs (001) substrate with a high density of 1×1011 cm-2. The photoluminescence properties have been studied for two periods of InAs quantum dots layers embedded in GaN0.007As0.993 strain compensating layers. Four well-resolved excited-state peaks in the photoluminescence spectra have been observed from these highly packed InAs QDs embedded in the GaN0.007As0.993 strain compensating layers. This indicates that the InAs QDs are uniformly formed and that the excited states in QDs due to the quantum confinement effect are well defined. This is explained by tensile strain in GaNAs layers instead of the usual GaAs layers to relieve the compressive strain formed in InAs QDs to keep the total strain of the system at a minimum.

  14. Age, Women, and Hiring: An Experimental Study

    ERIC Educational Resources Information Center

    Lahey, Joanna N.

    2008-01-01

    As baby boomers reach retirement age, demographic pressures on public programs may cause policy makers to cut benefits and encourage employment at later ages. But how much demand exists for older workers? This paper reports on a field experiment to determine hiring conditions for older women in entry-level jobs in two cities. A younger worker is…

  15. Hydra, a powerful model for aging studies

    PubMed Central

    Tomczyk, Szymon; Fischer, Kathleen; Austad, Steven; Galliot, Brigitte

    2015-01-01

    Cnidarian Hydra polyps escape senescence, most likely due to the robust activity of their three stem cell populations. These stem cells continuously self-renew in the body column and differentiate at the extremities following a tightly coordinated spatial pattern. Paul Brien showed in 1953 that in one particular species, Hydra oligactis, cold-dependent sexual differentiation leads to rapid aging and death. Here, we review the features of this inducible aging phenotype. These cellular alterations, detected several weeks after aging was induced, are characterized by a decreasing density of somatic interstitial cell derivatives, a disorganization of the apical nervous system, and a disorganization of myofibers of the epithelial cells. Consequently, tissue replacement required to maintain homeostasis, feeding behavior, and contractility of the animal are dramatically affected. Interestingly, this aging phenotype is not observed in all H. oligactis strains, thus providing a powerful experimental model for investigations of the genetic control of aging. Given the presence in the cnidarian genome of a large number of human orthologs that have been lost in ecdysozoans, such approaches might help uncover novel regulators of aging in vertebrates. PMID:26120246

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

    PubMed

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

    2011-12-01

    The objective of this study was to present the computerized structure that enables the use of the Nursing Activities Score (NAS) in mobile technology. It is a project for the development of technology production based on software engineering, founded on the theory of systems development life cycle. The NAS system was built in two modules: the search module, which is accessed using a personal computer (PC), and Data Collection module, which is accessed through a mobile device (Smartphone). The NAS system was constructed to allow other forms, in addition to the NAS tool, to be included in the future. Thus, it is understood that the development of the NAS will bring nurses closer to mobile technology and facilitate their accessibility to the data of the instrument relating to patients, thus assisting in decision-making and in staffing to provide nursing care. PMID:22241201

  17. 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…

  18. 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.

  19. 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

  20. NAS Applications and Advanced Algorithms

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

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

  1. 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.

  2. The Stability of Genetic Determination from Age 2 to Age 9: A Longitudinal Twin Study.

    ERIC Educational Resources Information Center

    Lytton, Hugh; And Others

    A longitudinal investigation of the social and cognitive development of male twins was conducted when twins were 2.5 years of age, and again when they were 8- to 10-years-old. This study was designed to re-examine the heritability of the traits studied at the earlier age and, thus, to address the question of the stability of genetic determination.…

  3. 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)

  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. 1H NMR metabolomics study of age profiling in children

    PubMed Central

    Gu, Haiwei; Pan, Zhengzheng; Xi, Bowei; Hainline, Bryan E.; Shanaiah, Narasimhamurthy; Asiago, Vincent; Nagana Gowda, G. A.; Raftery, Daniel

    2014-01-01

    Metabolic profiling of urine provides a fingerprint of personalized endogenous metabolite markers that correlate to a number of factors such as gender, disease, diet, toxicity, medication, and age. It is important to study these factors individually, if possible to unravel their unique contributions. In this study, age-related metabolic changes in children of age 12 years and below were analyzed by 1H NMR spectroscopy of urine. The effect of age on the urinary metabolite profile was observed as a distinct age-dependent clustering even from the unsupervised principal component analysis. Further analysis, using partial least squares with orthogonal signal correction regression with respect to age, resulted in the identification of an age-related metabolic profile. Metabolites that correlated with age included creatinine, creatine, glycine, betaine/TMAO, citrate, succinate, and acetone. Although creatinine increased with age, all the other metabolites decreased. These results may be potentially useful in assessing the biological age (as opposed to chronological) of young humans as well as in providing a deeper understanding of the confounding factors in the application of metabolomics. PMID:19441074

  6. New NAS Parallel Benchmarks Results

    NASA Technical Reports Server (NTRS)

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

    1997-01-01

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

  7. 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.

  8. 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).

  9. 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.

  10. 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…

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

    ERIC Educational Resources Information Center

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

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

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

    ERIC Educational Resources Information Center

    Snowdon, David A.

    1997-01-01

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

  13. 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…

  14. 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

  15. Characterizing healthy samples for studies of human cognitive aging

    PubMed Central

    Geldmacher, David S.; Levin, Bonnie E.; Wright, Clinton B.

    2012-01-01

    Characterizing the cognitive declines associated with aging, and differentiating them from the effects of disease in older adults, are important goals for human neuroscience researchers. This is also an issue of public health urgency in countries with rapidly aging populations. Progress toward understanding cognitive aging is complicated by numerous factors. Researchers interested in cognitive changes in healthy older adults need to consider these complexities when they design and interpret studies. This paper addresses important factors in study design, patient demographics, co-morbid and incipient medical conditions, and assessment instruments that will allow researchers to optimize the characterization of healthy participants and produce meaningful and generalizable research outcomes from studies of cognitive aging. Application of knowledge from well-designed studies should be useful in clinical settings to facilitate the earliest possible recognition of disease and guide appropriate interventions to best meet the needs of the affected individual and public health priorities. PMID:22988440

  16. 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

  17. 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)

  18. 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

  19. 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.

  20. 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

  1. 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

  2. Creativity and Occupational Accomplishments Among Intellectually Precocious Youths: An Age 13 to Age 33 Longitudinal Study

    ERIC Educational Resources Information Center

    Wai, Jonathan; Lubinski, David; Benbow, Camilla P.

    2005-01-01

    This study tracks intellectually precocious youths (top 1%) over 20 years. Phase 1 (N = 1,243 boys, 732 girls) examines the significance of age 13 ability differences within the top 1% for predicting doctorates, income, patents, and tenure at U.S. universities ranked within the top 50. Phase 2 (N = 323 men, 188 women) evaluates the robustness of…

  3. Cohort profile: The Berlin Aging Study II (BASE-II).

    PubMed

    Bertram, Lars; Böckenhoff, Anke; Demuth, Ilja; Düzel, Sandra; Eckardt, Rahel; Li, Shu-Chen; Lindenberger, Ulman; Pawelec, Graham; Siedler, Thomas; Wagner, Gert G; Steinhagen-Thiessen, Elisabeth

    2014-06-01

    Similar to other industrialized countries, Germany's population is ageing. Whereas some people enjoy good physical and cognitive health into old age, others suffer from a multitude of age-related disorders and impairments which reduce life expectancy and affect quality of life. To identify and characterize the factors associated with 'healthy' vs. 'unhealthy' ageing, we have launched the Berlin Aging Study II (BASE-II), a multidisciplinary and multi-institutional project that ascertains a large number of ageing-related variables from a wide range of different functional domains. Phenotypic assessments include factors related to geriatrics and internal medicine, immunology, genetics, psychology, sociology and economics. Baseline recruitment of the BASE-II cohort was recently completed and has led to the sampling of 1600 older adults (age range 60-80 years), as well as 600 younger adults (20-35 years) serving as the basic population for in-depth analyses. BASE-II data are linked to the German Socio-Economic Panel Study (SOEP), a long-running panel survey representative of the German population, to estimate sample selectivity. A major goal of BASE-II is to facilitate collaboration with other research groups by freely sharing relevant phenotypic and genotypic data with qualified outside investigators. PMID:23505255

  4. Maternal age and birth defects: a population study.

    PubMed

    Baird, P A; Sadovnick, A D; Yee, I M

    1991-03-01

    Since more and more women in developed countries are delaying childbearing to an older age, it is important to find out whether birth defects, other than those resulting from chromosomal anomalies, are related to maternal age. We have studied all 26,859 children with birth defects of unknown aetiology identified among 576,815 consecutive livebirths in British Columbia. All these cases' records were linked with provincial birth records to allow determination of maternal age at birth. We excluded children with chromosomal anomalies and those with other birth defects of known aetiology. Only 3 of the 43 birth defect categories studied showed significant maternal-age-specific trends: there were decreasing linear trends with maternal age for patent ductus arteriosus (chi 2 = 36.65, 1 df, p less than 0.01) and hypertrophic pyloric stenosis (chi 2 = 4.90, 1 df, p less than 0.05) and a bell-shaped curve (risk increasing to maternal age 30 then falling) for congenital dislocatable hip/hip click. The findings from this population-based analysis of no association between the incidence of birth defects of unknown aetiology and advancing maternal age should be reassuring to healthy women who opt to delay childbearing. PMID:1671898

  5. Age differences in learning maintenance skills: a field study.

    PubMed

    Delgoulet, Catherine; Marquié, Jean Claude

    2002-01-01

    The effects of age and previous relevant experience on learning anxiety, strategies, and performance were studied in 43 workers aged 25 to 49 during a 1-week maintenance vocational training course. The results showed that increased age was associated with higher training-related anxiety as measured at the beginning of the course. However, no age difference could be found in the level of knowledge assessed after 3 days of training. This was confirmed by another problem-solving-type test that took place on the last day. Previous experience had no effect on anxiety, and it did enable us to predict higher scores for the first test but not for the second one. Analysis of behavior strategies revealed that older trainees consulted and annotated the course material more often than the younger ones during the learning process. The results are discussed in relation to those obtained in previous laboratory and field studies on the same subject. PMID:11928208

  6. Cerebral microbleeds and age-related macular degeneration: the AGES-Reykjavik Study.

    PubMed

    Qiu, Chengxuan; Cotch, Mary Frances; Sigurdsson, Sigurdur; Eiriksdottir, Gudny; Jonasson, Fridbert; Klein, Ronald; Klein, Barbara E K; Harris, Tamara B; van Buchem, Mark A; Gudnason, Vilmundur; Launer, Lenore J

    2012-12-01

    We test the hypothesis that cerebral microbleeds (CMB) and age-related macular degeneration (AMD), both linked to amyloid-β deposition, are correlated. This study includes 4205 participants (mean age 76.2; 57.8% women) in the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study (2002-2006). CMB were assessed from magnetic resonance images, and AMD was assessed using digital retinal images. Data were analyzed with multinomial logistic models controlling for major confounders. Evidence of CMB was detected in 476 persons (272 with strict lobar CMB and 204 with nonlobar CMB). AMD was detected in 1098 persons (869 with early AMD, 140 with exudative AMD, and 89 with pure geographic atrophy). Early and exudative AMD were not associated with CMB. The adjusted odds ratio of pure geographic atrophy was 1.62 (95% confidence interval 0.93-2.82, p = 0.089) for having any CMB, 1.43 (0.66-3.06, p = 0.363) for strict lobar CMB, and 1.85 (0.89-3.87, p = 0.100) for nonlobar CMB. This study provides no evidence that amyloid deposits in the brain and AMD are correlated. However, the suggestive association of geographic atrophy with CMB warrants further investigation. PMID:22382405

  7. 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

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

    ERIC Educational Resources Information Center

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

    2013-01-01

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

  9. 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.

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

    PubMed Central

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

    2016-01-01

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

  11. Sepsis in Old Age: Review of Human and Animal Studies

    PubMed Central

    Starr, Marlene E; Saito, Hiroshi

    2014-01-01

    Sepsis is a serious problem among the geriatric population as its incidence and mortality rates dramatically increase with advanced age. Despite a large number of ongoing clinical and basic research studies, there is currently no effective therapeutic strategy that rescues elderly patients with severe sepsis. Recognition of this problem is relatively low as compared to other age-associated diseases. The disparity between clinical and basic studies is a problem, and this is likely due, in part, to the fact that most laboratory animals used for sepsis research are not old while the majority of sepsis cases occur in the geriatric population. The objective of this article is to review recent epidemiological studies and clinical observations, and compare these with findings from basic laboratory studies which have used aged animals in experimental sepsis. PMID:24729938

  12. Aging and generational effects on drinking behaviors in men: results from the normative aging study.

    PubMed Central

    Glynn, R J; Bouchard, G R; LoCastro, J S; Laird, N M

    1985-01-01

    The effects of aging on alcohol consumption behaviors are unclear because of confounding with period and cohort effects. In 1973, 1,859 male participants in the Normative Aging Study, born between 1892 and 1945, described their drinking behaviors by responding to a mailed questionnaire. In 1982, 1,713 of the participants in this study responded to a similar questionnaire. We used multivariate techniques, adjusting regression coefficients for the correlations between repeated responses of the same individuals, to assess the effects of birth cohort and aging on mean alcohol consumption level, on the prevalence of problems with drinking, and on the prevalence of averaging three or more drinks per day. Older men drank significantly less than younger men at both times yet there was no tendency for men to decrease their consumption levels over time. Each successively older birth cohort had a prevalence of problems with drinking estimated to be 0.037 lower than the prevalence of the next youngest cohort (95 per cent confidence interval: 0.029-0.045), yet there was no decrease in drinking problems over nine years. Interpretation of these findings requires consideration of the changes in attitudes as well as the increases in per capita consumption occurring in the United States throughout the 1970s. Results suggest that aging is not as important a factor in changes in drinking behaviors as generational or attitudinal changes. PMID:4061714

  13. 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

  14. 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. PMID:27221665

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

    PubMed Central

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

    2010-01-01

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

  16. 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.

  17. Neurological outcome in preterm small for gestational age infants compared to appropriate for gestational age preterm at the age of 18 months: a prospective study.

    PubMed

    Karagianni, Paraskevi; Kyriakidou, Maria; Mitsiakos, Georgios; Chatzioanidis, Helias; Koumbaras, Emmanouel; Evangeliou, Athanasios; Nikolaides, Nikolaos

    2010-02-01

    The aim of this study was to investigate the neurological outcome of premature small for gestational age infants at the corrected age of 18 months by the Hammersmith Infant Neurological Examination. A prospective trial was conducted comparing 41 preterm infants being small for gestational age with 41 appropriate for gestational age infants. Birth weight was significantly lower in small for gestational age infants compared with appropriate for gestational age infants (1724.6 +/- 433 versus 1221 +/- 328 g). There were no significant differences regarding the median gestational age and Apgar scores. Median global scores differ significantly between both groups: 75 (47-78) versus 76 (72-78) for the small for gestational age and appropriate for gestational age infants, respectively. Both groups had optimal scores. In conclusion, although the small for gestational age group scored lower in the Hammersmith Infant Neurological Examination, median global score in both groups was within optimal range. PMID:19372094

  18. 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

  19. 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.

  20. Suicidal behaviour in old age - results from the Ibadan study of ageing

    PubMed Central

    2013-01-01

    Background An important reason for the high risk of suicide in the elderly is the determination with which they act out their suicidal thoughts. Early identification of suicidal behaviours in the elderly is therefore important for suicide prevention efforts in this population. Method Data are from the Ibadan Study of Ageing (ISA), a household multi-stage probability sample of 2149 Yoruba Nigerians aged 65 years or older conducted between 2003 and 2004. We used the third version of the World Health Organization (WHO) Composite International Diagnostic Interview (CIDI) to explore suicidal experiences and behaviours. In this report, only those experiences or behaviours reported to have occurred after the age of 65 years are the focus of analysis. Derived weights were applied to the data in accordance with the study design and associations were explored using logistic regression. The results are presented as odds ratios (ORs) with 95% confidence intervals. Result In all, 4.0% (95% C.I= 3.1-4.2) of the subjects had suicidal ideation occurring after the age of 65 years, while 0.7% (95% C.I=0.4-1.3) and 0.2% (95% C.I= 0.1-0.4) reported suicidal plans and attempts, respectively. There was a significantly elevated likelihood of suicidal ideation among persons who had experienced spousal separation through death or divorce (O.R=4.9., 95% C.I= 1.5-15) or who were residing in rural settings (O.R=2.5, 95% C.I=1.3-4.8). Conclusion Suicidal ideation is common among the elderly. About 20% and 6% of those with ideation proceed to plans and attempts, respectively. Circumstances of social isolation and exclusion are important correlates of suicidal behaviour in the elderly. PMID:23497382

  1. EPA FABRIC FILTRATION STUDIES: 4. BAG AGING EFFECTS

    EPA Science Inventory

    The report gives results of a study to determine the effects of aging on filter bags made of woven polyester. Fabric filter life can be divided into three periods: break-in, steady-state, and wear-out. During the break-in, both bag collection efficiency and the pressure drop acro...

  2. 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…

  3. 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)

  4. Wealth and mortality at older ages: a prospective cohort study

    PubMed Central

    Demakakos, Panayotes; Biddulph, Jane P; Bobak, Martin; Marmot, Michael G

    2016-01-01

    Background Despite the importance of socioeconomic position for survival, total wealth, which is a measure of accumulation of assets over the life course, has been underinvestigated as a predictor of mortality. We investigated the association between total wealth and mortality at older ages. Methods We estimated Cox proportional hazards models using a sample of 10 305 community-dwelling individuals aged ≥50 years from the English Longitudinal Study of Ageing. Results 2401 deaths were observed over a mean follow-up of 9.4 years. Among participants aged 50–64 years, the fully adjusted HRs for mortality were 1.21 (95% CI 0.92 to 1.59) and 1.77 (1.35 to 2.33) for those in the intermediate and lowest wealth tertiles, respectively, compared with those in the highest wealth tertile. The respective HRs were 2.54 (1.27 to 5.09) and 3.73 (1.86 to 7.45) for cardiovascular mortality and 1.36 (0.76 to 2.42) and 2.53 (1.45 to 4.41) for other non-cancer mortality. Wealth was not associated with cancer mortality in the fully adjusted model. Similar but less strong associations were observed among participants aged ≥65 years. The use of repeated measurements of wealth and covariates brought about only minor changes, except for the association between wealth and cardiovascular mortality, which became less strong in the younger participants. Wealth explained the associations between paternal occupation at age 14 years, education, occupational class, and income and mortality. Conclusions There are persisting wealth inequalities in mortality at older ages, which only partially are explained by established risk factors. Wealth appears to be more strongly associated with mortality than other socioeconomic position measures. PMID:26511887

  5. Genome-Scale Studies of Aging: Challenges and Opportunities

    PubMed Central

    McCormick, Mark A; Kennedy, Brian K

    2012-01-01

    Whole-genome studies involving a phenotype of interest are increasingly prevalent, in part due to a dramatic increase in speed at which many high throughput technologies can be performed coupled to simultaneous decreases in cost. This type of genome-scale methodology has been applied to the phenotype of lifespan, as well as to whole-transcriptome changes during the aging process or in mutants affecting aging. The value of high throughput discovery-based science in this field is clearly evident, but will it yield a true systems-level understanding of the aging process? Here we review some of this work to date, focusing on recent findings and the unanswered puzzles to which they point. In this context, we also discuss recent technological advances and some of the likely future directions that they portend. PMID:23633910

  6. Age coarsening of colloidal gels: a micro-mechanical study

    NASA Astrophysics Data System (ADS)

    Zia, Roseanna; Landrum, Benjamin; Russel, William

    2013-11-01

    We study the evolving structure and time-dependent rheological properties of an aging colloidal gel, with a focus on understanding the non-equilibrium forces that drive late-age coarsening. The gel is formed from a dispersion of Brownian hard spheres that interact via a hard-sphere repulsion and short-range attraction. The O(kT) strength of attractions lead to an arrested phase separation, and the resulting structure is a bi-continuous, space-spanning network that exhibits elastic and viscous behaviors: the gel may sustain its weight under gravity, or flow under shear. With weak attractions the bonds are reversible, giving rise to a continuous breakage / formation process as the gel ages. This balance favors coarsening over time, accompanied by an increase in feature size and elastic strength. We show here that anisotropic surface migration leads to heterogeneous coarsening, and that this migration is driven by gradients in particle-phase stress.

  7. Biomarkers of aging and falling: the Beaver Dam eye study

    PubMed Central

    Knudtson, Michael D.; Klein, Barbara E. K.; Klein, Ronald

    2009-01-01

    Falls are an important cause of morbidity in older adults and are an important source of health care spending. We hypothesize that falls are associated with systemic biomarkers of aging. The following functions, measured at the 1998–2000 and 2003–05 examinations of the Beaver Dam Eye study, were considered to be biomarkers of aging (frailties): poorer visual acuity, contrast sensitivity or discrepant vision between the eyes, inability to rise from a chair, slower gait time, poorer hand grip strength, and lower peak expiratory flow rate. We found that poorer values on biomarkers of aging (frailties) at the 1998–2000 examination were associated with 2 or more reported falls in the past year at the 2003–05 examination (p < 0.05 for all markers except peak expiratory flow rate). When the markers were combined as an index of biological aging (frailty), the index was significantly associated with falls after controlling for significant confounders (odds ratio per 1 step increase in the index: 1.33; 95% confidence interval = CI = 1.13–1.57) We conclude that biomarkers of aging, including any of three measures of visual function, are associated with falls. Improvement in these functional measures may lead to decreased risk of falls. PMID:18513808

  8. 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

  9. The nasFEDCBA operon for nitrate and nitrite assimilation in Klebsiella pneumoniae M5al.

    PubMed

    Lin, J T; Goldman, B S; Stewart, V

    1994-05-01

    Klebsiella pneumoniae can use nitrate and nitrite as sole nitrogen sources through the nitrate assimilation pathway. We previously identified structural genes for assimilatory nitrate and nitrite reductases, nasA and nasB, respectively. We report here our further identification of four genes, nasFEDC, upstream of the nasBA genes. The nasFEDCBA genes probably form an operon. Mutational and complementation analyses indicated that both the nasC and nasA genes are required for nitrate assimilation. The predicted NASC protein is homologous to a variety of NADH-dependent oxidoreductases. Thus, the NASC protein probably mediates electron transfer from NADH to the NASA protein, which contains the active site for nitrate reduction. The deduced NASF, NASE, and NASD proteins are homologous to the NRTA, NRTB, and NRTD proteins, respectively, that are involved in nitrate uptake in Synechococcus sp. (T. Omata, X. Andriesse, and A. Hirano, Mol. Gen. Genet. 236:193-202, 1993). Mutational and complementation studies indicated that the nasD gene is required for nitrate but not nitrite assimilation. By analogy with the Synechococcus nrt genes, we propose that the nasFED genes are involved in nitrate transport in K. pneumoniae. PMID:8169203

  10. The nasFEDCBA operon for nitrate and nitrite assimilation in Klebsiella pneumoniae M5al.

    PubMed Central

    Lin, J T; Goldman, B S; Stewart, V

    1994-01-01

    Klebsiella pneumoniae can use nitrate and nitrite as sole nitrogen sources through the nitrate assimilation pathway. We previously identified structural genes for assimilatory nitrate and nitrite reductases, nasA and nasB, respectively. We report here our further identification of four genes, nasFEDC, upstream of the nasBA genes. The nasFEDCBA genes probably form an operon. Mutational and complementation analyses indicated that both the nasC and nasA genes are required for nitrate assimilation. The predicted NASC protein is homologous to a variety of NADH-dependent oxidoreductases. Thus, the NASC protein probably mediates electron transfer from NADH to the NASA protein, which contains the active site for nitrate reduction. The deduced NASF, NASE, and NASD proteins are homologous to the NRTA, NRTB, and NRTD proteins, respectively, that are involved in nitrate uptake in Synechococcus sp. (T. Omata, X. Andriesse, and A. Hirano, Mol. Gen. Genet. 236:193-202, 1993). Mutational and complementation studies indicated that the nasD gene is required for nitrate but not nitrite assimilation. By analogy with the Synechococcus nrt genes, we propose that the nasFED genes are involved in nitrate transport in K. pneumoniae. PMID:8169203

  11. 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

  12. Do hassles and uplifts change with age? Longitudinal findings from the VA normative aging study.

    PubMed

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

    2014-03-01

    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 3 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. Group-based modeling showed individual differences in patterns of hassles and uplifts intensity and exposure, with relative stability in uplifts intensity, normative nonlinear 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

  13. DNA methylation of oxidative stress genes and cancer risk in the Normative Aging Study

    PubMed Central

    Gao, Tao; Joyce, Brian Thomas; Liu, Lei; Zheng, Yinan; Dai, Qi; Zhang, Zhou; Zhang, Wei; Shrubsole, Martha J; Tao, Meng-Hua; Schwartz, Joel; Baccarelli, Andrea; Hou, Lifang

    2016-01-01

    Oxidative stress (OS) is a primary mechanism of carcinogenesis, and methylation of genes related to it may play a role in cancer development. In this study, we examined the prospective association between blood DNA methylation of four oxidative stress genes and cancer incidence. Our study population included a total of 582 participants in the Normative Aging Study (NAS) who had blood drawn during 1-4 visits from 1999-2012 (mean follow up 9.0 years). Promoter DNA methylation of CRAT, iNOS, OGG1 and GCR in blood leukocytes was measured using pyrosequencing. We used Cox regression models to examine prospective associations between cancer incidence and both methylation at the baseline visit and methylation rate of changes over time. Baseline OGG1 methylation was associated with higher risk of all-cancer (HR: 1.43, 95% CI: 1.15-1.78) and prostate cancer (HR: 1.52, 95% CI: 1.03-2.25) incidence. Compared with participants remaining cancer-free, those who eventually developed cancer had significantly accelerated CRAT methylation (p = 0.04) and decelerated iNOS methylation (p<0.01) over time prior to cancer diagnosis. Accelerated CRAT methylation was associated with higher all-cancer incidence (HR: 3.88, 95% CI: 1.06-14.30), whereas accelerated iNOS methylation was associated with lower all-cancer incidence (HR: 0.08, 95% CI 0.02-0.38). Our results suggest that methylation and its dynamic change over time in OS-related genes, including OGG1, CRAT and iNOS, may play an important role in carcinogenesis. These results can potentially facilitate the development of early detection biomarkers and new treatments for a variety of cancers. PMID:27186424

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

    PubMed

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

    2014-02-01

    A rapidly aging global population has motivated the development and use of models for human aging. Studies on aging have shown parallels between zebrafish and humans at the internal organization level; however, few parallels have been studied at the whole-organism level. Furthermore, the effectiveness of exercise as a method to mitigate the effects of aging has not been studied in zebrafish. We investigated the effects of aging and intermittent exercise on swimming performance, kinematics and behavior. Young, middle-aged and old zebrafish (20-29, 36-48 and 60-71% of average lifespan, respectively) were exercised to exhaustion in endurance and sprint swimming tests once a week for four weeks. Both endurance and sprint performance decreased with increased age. Swimming performance improved with exercise training in young and middle-aged zebrafish, but not in old zebrafish. Tail-beat amplitude, which is akin to stride length in humans, increased for all age groups with training. Zebrafish turning frequency, which is an indicator of routine activity, decreased with age but showed no change with exercise. In sum, our results show that zebrafish exhibit a decline in whole-organism performance and trainability with age. These findings closely resemble the senescence-related declines in physical ability experienced by humans and mammalian aging models and therefore support the use of zebrafish as a model for human exercise and aging. PMID:24316042

  15. 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.

  16. 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…

  17. Aging studies for the muon detector of HERA-B

    NASA Astrophysics Data System (ADS)

    Danilov, M.; Guilitsky, Yu.; Kvaratschellia, T.; Tikhomirov, I.; Titov, M.; Zaitsev, Yu.

    2003-12-01

    The severe radiation environment of the HERA-B experiment leads to a maximum accumulated charge on a wire, within the muon detector, of 200 mC/cm wire . For operation in this high-intensity environment, the main criteria for the gas choice turned out to be stability against aging. We report recent results of aging studies performed by irradiating aluminum proportional wire chambers filled with Ar/CF 4/CH 4 (74:20:6), Ar/CF 4/CH 4 (67:30:3), Ar/CF 4/CO 2 (65:30:5) Ar/CF 4 (70:30), CF 4/CH 4 (90:10) and CF 4/CH 4 (80:20) mixtures in three different experimental setups: laboratory conditions ( 55Fe and 106Ru sources), a 100 MeV α -beam and the high-rate HERA-B environment (secondaries from interactions of 920 GeV protons with target nucleus). Our experience shows that the aging rate depends not only on the total collected charge, but, in addition, on the mode of operation (high voltage and/or gas gain) and area of irradiation. Effects of CF 4 addition on aging performance of gaseous detectors are summarized. Possible application of these results for operation of large scale gaseous detectors in the high rate environment is discussed.

  18. Online aging study of a high rate MRPC

    NASA Astrophysics Data System (ADS)

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

    2016-05-01

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

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

    PubMed Central

    Brüssow, Harald

    2013-01-01

    Summary Hundred years ago Metchnikoff associated human health and particularly healthy ageing with a specific type of gut microbiota. Classical culture methods associated a decrease in bifidobacteria and an increase in enterobacteria with ageing. Modern molecular methods blurred this simple picture and documented a substantial inter-individual variability for the gut microbiome even when stratifying the elderly subjects according to health status. Nutritional interventions with resistant starch showed consistent gut microbiota changes across studies from different geographical areas and prebiotic supplementation induced a 10-fold increase in gut bifidobacteria. However, in the ELDERMET study, microbiota changes do not precede, but follow the changes in health status of elderly subjects possibly as a consequence of diet changes. PMID:23527905

  20. 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.

  1. 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

  2. Effect of age at exposure in 11 underground miners studies.

    PubMed

    Tomasek, L

    2014-07-01

    Eleven underground miners studies evaluated the risk of lung cancer from exposure in underground mines. Nearly 68,000 miners were included in the joint study, contributing to nearly 2700 lung cancers. The resulting model of the Biological Effects of Ionizing Radiation (BEIR) VI Committee considered linear exposure response relationship, which was modified by time since exposure (TE), attained age and exposure rate. The effect of age at exposure (AE) was not explicitly evaluated. The presentation aims to show that the modifying effect of AE is substantial if time-since-exposure modification is simultaneously used in the model. When the excess relative risk per unit exposure (ERR/WLM) is adjusted for TE, the ERR/WLM corresponding to AE<15 is 0.013 and in subsequent categories decreased gradually up to the AE of 40 and more years, which was only 0.004. In comparison with the BEIR VI model, the present model predicts higher risks at younger ages and the risk decreases more rapidly. PMID:24751983

  3. 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

  4. NasR, a novel RNA-binding protein, mediates nitrate-responsive transcription antitermination of the Klebsiella oxytoca M5al nasF operon leader in vitro.

    PubMed

    Chai, W; Stewart, V

    1998-10-23

    In Klebsiella oxytoca (pneumoniae), enzymes required for nitrate assimilation are encoded by the nasFEDCBA operon. Previous genetic studies led to the conclusion that nitrate and nitrite induction of nasF operon expression is determined by a transcriptional antitermination mechanism. In the presence of nitrate or nitrite, the nasR gene product is hypothesized to inhibit transcription termination at the factor-independent terminator site located in the nasF operon leader region. To test this model in vitro, we first purified NasR as both a maltose binding protein fusion form (MBP-NasR) and a His6-tagged form (His6-NasR). Templates for in vitro transcription contained the nasF operon leader region, with a substitution of the sigma70-dependent tac promoter for the native sigmaN-dependent promoter. We found that in vitro transcription of the leader template terminated at the terminator site, and that MBP-NasR and His6-NasR proteins both caused transcription readthrough of this site in response to nitrate or nitrite. Half-maximal antitermination required nitrate or nitrite at moderate (1 to 10 microM) concentrations, and several other anions tested, including chlorate, were without effect. Previous in vivo analysis of leader deletions identified regions required for both negative regulation (the terminator) and for positive regulation. Results from in vitro transcription of these deletion templates correlated fully with the in vivo analysis. Finally, electrophoresis mobility shift analysis revealed that His6-NasR bound specifically to nasF leader RNA. This binding was independent of nitrate in vitro. These results strongly support the conclusions drawn from previous in vivo analysis, and establish that NasR mediates ligand-responsive transcription antitermination through interaction with nasF leader RNA. PMID:9769209

  5. 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.

  6. Deaths among women of reproductive age: a forensic autopsy study.

    PubMed

    Padubidri, Jagadish Rao; Menezes, Ritesh G; Pant, Sadip; Shetty, Soumya B

    2013-08-01

    Unnatural deaths in women of reproductive age (range 12-49 years) have a serious psychological and social impact on the family and community. Deaths among women of reproductive age reported as medico-legal cases were investigated to see the trend in terms of cause and manner of death. The study group consisted of a series of 328 consecutive forensic autopsies on women in the reproductive age group, performed between 2009 and 2011 at the Government Wenlock District Hospital, Mangalore, India by qualified specialist forensic medicine experts. Unnatural deaths formed 93.6% of the cohort. The top three causes of death included burns, poisoning and hanging forming 69.5% of the cases. The manner of death was suicide in 45.4% cases, accident in 43.6% cases and homicide in 4.6% cases. The circumstances of death were related to alleged medical negligence in 2.4% cases. Death in 4% cases was natural mannered with a disease being the cause of death. Three-fourths of the victims were married. Married women formed 63.1% of the suicidal victims. Homicidal deaths were not reported among unmarried women. The preponderant method of suicide was by poisoning at 42.3% (63 cases), followed by hanging (34.9%), burns (11.4%) and drowning (9.4%). These four methods comprised 98% of the total suicidal deaths in this study cohort. Accidental deaths were predominantly caused by burns (62.2%) and road traffic accident (23.1%). Two-thirds of the homicidal deaths were due to assault caused by blunt-force trauma, ligature strangulation and sharp-force trauma. One-third of the homicidal victims died due to burns. With a clear understanding of the cause and manner of death, it may be possible to predict, and hopefully prevent, future cases of unnatural deaths in women of reproductive age who form a very important group of society. PMID:23910855

  7. 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.

  8. "Old Age and Loneliness: Cross-Sectional and Longitudinal Analyses in the Tampere Longitudinal Study on Aging"

    ERIC Educational Resources Information Center

    Jylha, Marja

    2004-01-01

    The purpose of this study was to examine whether older age is associated with increasing loneliness in people aged 60 and over. Data came from TamELSA, a population-based prospective longitudinal study in Tampere, Finland. The followup time was 20 years. Loneliness was measured by a single question--"Do you feel lonely?"--with the possible answers…

  9. 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.…

  10. 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.

  11. 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.

  12. 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.

  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. 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.

  15. Genome-wide identification, classification and expression profiling of nicotianamine synthase (NAS) gene family in maize

    PubMed Central

    2013-01-01

    Background Nicotianamine (NA), a ubiquitous molecule in plants, is an important metal ion chelator and the main precursor for phytosiderophores biosynthesis. Considerable progress has been achieved in cloning and characterizing the functions of nicotianamine synthase (NAS) in plants including barley, Arabidopsis and rice. Maize is not only an important cereal crop, but also a model plant for genetics and evolutionary study. The genome sequencing of maize was completed, and many gene families were identified. Although three NAS genes have been characterized in maize, there is still no systematic identification of maize NAS family by genomic mining. Results In this study, nine NAS genes in maize were identified and their expression patterns in different organs including developing seeds were determined. According to the evolutionary relationship and tissue specific expression profiles of ZmNAS genes, they can be subgrouped into two classes. Moreover, the expression patterns of ZmNAS genes in response to fluctuating metal status were analysed. The class I ZmNAS genes were induced under Fe deficiency and were suppressed under Fe excessive conditions, while the expression pattern of class II genes were opposite to class I. The complementary expression patterns of class I and class II ZmNAS genes confirmed the classification of this family. Furthermore, the histochemical localization of ZmNAS1;1/1;2 and ZmNAS3 were determined using in situ hybridization. It was revealed that ZmNAS1;1/1;2, representing the class I genes, mainly expressed in cortex and stele of roots with sufficient Fe, and its expression can expanded in epidermis, as well as shoot apices under Fe deficient conditions. On the contrary, ZmNAS3, one of the class II genes, was accumulated in axillary meristems, leaf primordia and mesophyll cells. These results suggest that the two classes of ZmNAS genes may be regulated on transcriptional level when responds to various demands for iron uptake, translocation

  16. Photochemical Aging of Organic Aerosols: A Laboratory Study

    NASA Astrophysics Data System (ADS)

    Papanastasiou, Dimitrios K.; Kostenidou, Evangelia; Gkatzelis, Georgios I.; Psichoudaki, Magdalini; Louvaris, Evangelos; Pandis, Spyros N.

    2014-05-01

    Organic aerosols (OA) are either emitted directly (primary OA) or formed (secondary OA) in the atmosphere and consist of an extremely complex mixture of thousands of organic compounds. Although the scientific community has put significant effort, in the past few decades, to understand organic aerosol (OA) formation, evolution and fate in the atmosphere, traditional models often fail to reproduce the ambient OA levels. Secondary organic aerosol (SOA) formed, in traditional laboratory chamber experiments, from the gas phase oxidation of known precursors, such as α-pinene, is semi-volatile and with an O:C ratio of around 0.4. In contrast, OA found in the atmosphere is significantly less volatile, while the O:C ratio often ranges from 0.5 to 1. In conclusion, there is a significant gap of knowledge in our understanding of OA formation and photochemical transformation in the atmosphere. There is increased evidence that homogeneous gas phase aging by OH radicals might be able to explain, at least in part, the significantly higher OA mass loadings observed and also the oxidation state and volatility of OA in the atmosphere. In this study, laboratory chamber experiments were performed to study the role of the continued oxidation of first generation volatile and semi-volatile species by OH radicals in the evolution of the SOA characteristics (mass concentration, volatility, and oxidation state). Ambient air mixtures or freshly formed SOA from α-pinene ozonolysis were used as the source of organic aerosols and semi-volatile species. The initial mixture of organic aerosols and gas phase species (volatile and semi-volatile) was then exposed to atmospheric concentrations of OH radicals to study the aging of aerosols. Experiments were performed with various OH radical sources (H2O2 or HONO) and under various NOx conditions. A suite of instruments was employed to characterize both the gas and the aerosol phase. A Scanning Mobility Particle Sizer (SMPS) and a High

  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. 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

  19. 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

  20. Coping with multimorbidity in old age – a qualitative study

    PubMed Central

    2012-01-01

    Background Comparatively few studies address the problems related to multimorbidity. This is surprising, since multimorbidity is a particular challenge for both general practitioners and patients. This study focuses on the latter, analyzing the way patients aged 65–85 cope with multimorbidity. Methods 19 narrative in-depth interviews with multimorbid patients were conducted. The data was analysed using grounded theory. Of the 19 interviewed patients 13 were female and 6 male. Mean age was 75 years. Participating patients showed a relatively homogeneous socio-economic status. Patients were recruited from the German city of Hamburg and the state of North Rhine-Westphalia. Results Despite suffering from multimorbidity, interviewees held positive attitudes towards life: At the social level, patients tried to preserve their autonomy to the most possible extent. At the emotional level, interviewees oscillated between anxiety and strength - having, however, a positive approach to life. At the practical level, patients aimed at keeping their diseases under control. The patients tended to be critical in regards to medication. Conclusions These findings might have implications for the treatment of multimorbid patients in primary care and further research: The generally presumed passivity of older individuals towards medical treatment, which can be found in literature, is not evident among our sample of older patients. In future, treatment of these patients might take their potential for pro-active cooperation more strongly into account than it is currently the case. PMID:22639848

  1. Alternative conceptions in animal classification: A cross-age study

    NASA Astrophysics Data System (ADS)

    Trowbridge, John E.; Mintzes, Joel J.

    Employing a cross-age design, this study examined students' alternative conceptions in animal classification at the elementary, secondary, and college levels. Based on a previous study that made use of clinical interviews and a classification task, subjects (N = 468) were administered a multiple-choice/free-response instrument that probed understanding of the concept animal, the vertebrate/invertebrate distinction, and the principal vertebrate classes. Results suggest that students subscribe to a highly restricted view of animals; applying the label almost exclusively to vertebrates, especially to common mammals. When asked to distinguish between vertebrate and invertebrate animals and to classify several species into vertebrate groups, a wide range of alternative conceptions emerged. Cross-age comparisons indicate that many of these alternative views remain intact throughout the school years, while others yield more readily to formal instruction and/or nonschool experiences. Considered within the context of a neoconstructivist view of learning, several suggestions are offered for teaching concepts in animal classification.

  2. Whole grain intake: The Baltimore Longitudinal Study of Aging

    PubMed Central

    Maras, Janice E.; Newby, P.K.; Bakun, Peter J.; Ferrucci, Luigi; Tucker, Katherine L.

    2009-01-01

    Our objective was to identify major dietary sources of whole grains and to describe the construction of a database of whole grain content of foods. Dietary information was collected with 7-d food records from men and women in the Baltimore Longitudinal Study of Aging, mean age 62.1 ± 16.0 years, who participated in the dietary assessment portion of the study (n = 1516), and estimates of whole grain intake were obtained from a newly developed database. The Pyramid Servings database and 1994–1996 Continuing Survey of Food Intakes by Individuals (CSFII) recipe ingredients database were then used to calculate both servings and gram weights of whole grain intakes. Mean intakes of whole grains, refined grains, and total grains, as well as frequency of intake for major whole grain food groups and whole grain content for each group, were calculated. Top contributors of whole grains were ready-to-eat breakfast cereals (made with whole grain as well as bran), hot breakfast cereals (made with whole grain), multi-grain bread, and whole wheat bread. While more research is needed to better understand the benefits of whole grains, the development of research tools, including databases to accurately assess whole grain intake, is a critical step in completing such research. PMID:20126297

  3. 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

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

    ERIC Educational Resources Information Center

    Hembacher, Diane; Cruise, Mary J.

    2006-01-01

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

  5. 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)

  6. 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

  7. 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.

  8. 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.

  9. Aging studies on thin tetra-phenyl butadiene films

    NASA Astrophysics Data System (ADS)

    Acciarri, R.; Canci, N.; Cavanna, F.; Segreto, E.; Szelc, A. M.

    2013-10-01

    Tetra-Phenyl Butadiene (TPB) is the most commonly used compound to wave-shift the 128 nm scintillation light of liquid Argon down to the visible spectrum. We present a study on the loss of conversion efficiency of thin TPB films evaporated on reflective foils when exposed to light and atmosphere. The efficiency of the films is measured and monitored with a dedicated set-up that uses gaseous Argon excited by alpha particles to produce 128 nm photons and working at room temperature. In particular we performed a two years long exposure of the samples to lab diffuse light and atmosphere. We also performed more controlled aging tests to investigate the effect of storing samples in a inert atmosphere.

  10. 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

  11. Neuroendocrine involvement in aging: evidence from studies of reproductive aging and caloric restriction.

    PubMed

    Nelson, J F; Karelus, K; Bergman, M D; Felicio, L S

    1995-01-01

    Neuroendocrine changes contribute to female reproductive aging, but changes in other tissues also play a role. In C57BL/6J mice, neuroendocrine changes contribute to estrous cycle lengthening and reduced plasma estradiol levels, but the midlife loss of cyclicity is mainly due to ovarian failure. Hypothalamic estrogen receptor dynamics and estrogenic modulation of gene expression are altered in middle-aged cycling mice. Although insufficient to arrest cyclicity, these neuroendocrine changes may contribute to other reproductive aging phenomena, such as altered gonadotropin secretion and lengthened estrous cycles. In women, the loss of ovarian oocytes, the cause of menopause, accelerates in the decade before menopause. Accelerated oocyte loss may in turn be caused by a selective elevation of plasma follicle stimulating hormone, and neuroendocrine involvement may thus be implicated in menopausal oocyte loss. Chronic calorie restriction retards both neural and ovarian reproductive aging processes, as well as age-related change in many other physiological systems. The diverse effects of food restriction raises the possibility of an underlying coordinated regulatory response of the organism to reduced caloric intake, possibly effected through alterations of neural and/or endocrine signalling. We are therefore attempting to identify neuroendocrine changes that may coordinate the life prolonging response of animals to food restriction. Our initial focus is on the glucocorticoid system. Food restricted rats exhibit daily periods of hyperadrenocorticism, manifest as elevated free corticosterone during the diurnal peak. We hypothesize that this hyperadrenocortical state potentiates cellular and organismic homeostasis throughout life in a manner similar to that achieved during acute stress, thereby retarding aging processes and extending life span. PMID:8532119

  12. Alcohol Intoxication in Pediatric Age: Ten-year Retrospective Study

    PubMed Central

    Bitunjac, Kristina; Saraga, Marijan

    2009-01-01

    Aim To examine the changes in the number of children younger than 18 who were hospitalized due to alcohol intoxication at the Department of Pediatrics, University Hospital of Split, from November 1, 1997 to October 31, 2007. Methods Data on children hospitalized due to intoxication were retrieved from hospital medical records. Children were classified into 4 age groups: 0-5, 6-9, 10-13, and 14-18 years, and their sex and type of intoxication were recorded. For children with alcohol intoxication, data on time of intoxication, reason for drinking, presence of injuries or suspected suicide attempts, and possible presence of other drugs in the organism were collected. Results Out of 29 506 hospitalized children, 594 were hospitalized due to intoxications. Out of these, 239 (40.2%) were hospitalized due to intoxication by alcohol. More boys than girls were hospitalized (71.1%). The proportion of alcohol intoxication cases among all types of intoxication cases increased from 16.7% in 1997/98 to 66.3% in 2006/07. The proportion of patients hospitalized due to alcohol intoxication increased from 0.3% of all hospitalized children in the first year to 1.7% in the last year of the study (P = 0.015, z test for comparison of two proportions). Eighty two per cent of cases of alcohol intoxication were in the 14-18 age-group. The number of alcohol intoxication cases increased among girls from 1 case (6.3% of all intoxication cases among girls) in 1997/98 to 15 cases (45.5%) in 2006/07, while among boys it increased from 6 cases (23.1% of all intoxicated boys) in 1997/98 to 44 cases (78.6%) in 2006/07. Children usually drank outside their homes (79.4%) and mostly on weekends and holidays (73.2%). Conclusion The alarming increase in the number of hospitalizations due to alcohol intoxication in children, especially among girls and in the adolescent age group, represents a serious problem, which requires further attention and research. PMID:19399948

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

    PubMed Central

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

    2015-01-01

    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. PMID:26629551

  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. 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…

  16. 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…

  17. Genome wide association study of age at puberty in swine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Age at puberty (AP) is an economically important trait in swine production. Reducing AP provides opportunities to lower the cost of gilt development, reduce age at first farrowing, increase litter size, and improve sow longevity. This analysis was designed to identify quantitative trait loci (QTL)...

  18. Psychological Studies of Aging: Their Origins, Development and Present Challenge.

    ERIC Educational Resources Information Center

    Welford, A. T.

    1992-01-01

    Considers needs and potentialities for application of fundamental psychological knowledge of aging in areas of industrial and other work, clinical assessment and intelligence testing, assessment of attitudes, and coping with everyday problems in old age and with interpersonal relationships, especially in old people's communities and between old…

  19. UAS Integration into the NAS Project

    NASA Technical Reports Server (NTRS)

    Bauer, Jeff

    2010-01-01

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

  20. 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…

  1. Retirement Age and the Age of Onset of Alzheimer’s Disease: Results from the ICTUS Study

    PubMed Central

    Grotz, Catherine; Letenneur, Luc; Bonsang, Eric; Amieva, Hélène; Meillon, Céline; Quertemont, Etienne; Salmon, Eric; Adam, Stéphane

    2015-01-01

    Objectives To test whether deferred retirement is associated with delayed onset of Alzheimer’s disease (AD), and, if so, to determine whether retirement age still predicts the age at onset of AD when two potential biases are considered. Methods The study sample was gathered from the Impact of Cholinergic Treatment Use/Data Sharing Alzheimer cohort (ICTUS/DSA), a European study of 1,380 AD patients. Information regarding retirement age, onset of symptoms and covariates was collected at baseline whereas age at diagnosis was gathered from the patient’s medical record prior to study entry. Linear mixed models, adjusted for gender, education, occupation, center, country, household income, depression and cardiovascular risk factors were conducted on 815 patients. Results (1) The global analyses (n = 815) revealed that later age at retirement was associated with later age at diagnosis (β = 0.31, p < 0.0001); (2) once the selection bias was considered (n = 637), results showed that this association was weaker but remained significant (β = 0.15, p = 0.004); (3) once the bias of the reverse causality (i.e., the possibility that subjects may have left the workforce due to prior cognitive impairment) was considered (n = 447), the effect was no longer significant (β = 0.06, p = 0.18). Conclusion The present study supports that there is an association between retirement age and age at onset of AD. However, the strength of this association appears to be overestimated due to the selection bias. Moreover, the causality issue remains unresolved. Further prospective investigations are mandatory in order to correctly address this question. PMID:25714815

  2. A large-scale candidate-gene association study of age at menarche and age at natural menopause

    PubMed Central

    Kraft, Peter; Chasman, Daniel I.; Buring, Julie E.; Chen, Constance; Hankinson, Susan E.; Paré, Guillaume; Chanock, Stephen; Ridker, Paul M.; Hunter, David J.

    2010-01-01

    Recent genome-wide association (GWA) studies have identified several novel genetic loci associated with age at menarche and age at natural menopause. However, the stringent significance threshold used in GWA studies potentially lead to false negatives and true associations may have been overlooked. Incorporating biologically relevant information, we examined whether common genetic polymorphisms in candidate genes of 9 groups of biologically plausible pathways and related phenotypes are associated with age at menarche and age at natural menopause. A total of 18,862 genotyped and imputed single nucleotide polymorphisms (SNPs) in 278 genes were assessed for their associations with these two traits among a total of 24,341 women from the Nurses’ Health Study (NHS, N=2,287) and the Women’s Genome Health Study (WGHS, N=22,054). Linear regression was used to assess the marginal association of each SNP with each phenotype. We adjusted for multiple testing within each gene to identify statistically significant SNP associations at the gene level. To evaluate the overall evidence for an excess of statistically significant gene associations over the proportion expected by chance, we applied a one-sample test of proportion to each group of candidate genes. The steroid-hormone metabolism and biosynthesis pathway was found significantly associated with both age at menarche and age at natural menopause (p=0.040 and 0.011, respectively). Additionally, the group of genes associated with precocious or delayed puberty was found significantly associated with age at menarche (p=0.013), and the group of genes involved in premature ovarian failure with age at menopause (p=0.025). PMID:20734064

  3. Stability and change in intelligence from age 12 to age 52: results from the Luxembourg MAGRIP study.

    PubMed

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

    2013-08-01

    The present longitudinal study tackled 2 key aspects of the development of intelligence across a 40-year time period from age 12 to age 52 concerning (a) stability and change in the structure of intelligence with reference to the age differentiation-dedifferentiation hypothesis (how different cognitive abilities relate to each other across age) and (b) differential stabilities (the rank ordering of persons' intelligence levels across time). To this end, we drew on 2 structural conceptions of intelligence: (a) the extended Gf-Gc model to study broad cognitive abilities and (b) the 3-stratum model to decompose cognitive change into processes that are shared by all broad abilities (attributable to general cognitive ability g) and processes specific to a certain ability (independent of g). Data were obtained for 344 persons (56.4% female). The results showed that people differ more greatly over time with respect to all broad abilities except for fluid reasoning, whereas the rank ordering of persons on all broad abilities remains remarkably stable. These combined results yielded substantial gap-widening effects from age 12 to age 52 years that were mainly accounted for by a substantial increase in g variance in combination with a high differential stability of g. Moreover, the increase in g variance reflects an increase in covariance among different broad abilities, which indicates that the different constructs relate more closely to each other at age 52 compared to age 12 (i.e., age dedifferentiation). Two theoretical explanations of this change in the structure of intelligence are discussed (common cause hypothesis and investment theory). PMID:23148935

  4. 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.

  5. Identification and functional analysis of a nitrate assimilation operon nasACKBDEF from Amycolatopsis mediterranei U32.

    PubMed

    Shao, Zhihui; Gao, Jin; Ding, Xiaoming; Wang, Jin; Chiao, Juishen; Zhao, Guoping

    2011-07-01

    Nitrate assimilation has been well studied for Gram-negative bacteria but not so much in the Gram-positive actinomycetes up to date. In a rifamycin SV-producing actinomycete, Amycolatopsis mediterranei strain U32, nitrate not only can be used as a sole nitrogen source but also remarkably stimulates the antibiotic production along with regulating the related metabolic enzymes. A gene cluster of nasACKBDEF was cloned from a U32 genomic library by in situ hybridization screening with a heterogeneous nasB probe and confirmed later by whole genome sequence, corresponding to the protein coding genes of AMED_1121 to AMED_1127. These genes were co-transcribed as an operon, concomitantly repressed by ammonium while activated with supplement of either nitrate or nitrite. Genetic and biochemical analyses identified the essential nitrate/nitrite assimilation functions of the encoded proteins, orderly, the assimilatory nitrate reductase catalytic subunit (NasA), nitrate reductase electron transfer subunit (NasC), nitrate/nitrite transporter (NasK), assimilatory nitrite reductase large subunit (NasB) and small subunit (NasD), bifunctional uroporphyrinogen-III synthase (NasE), and an unknown function protein (NasF). Comparing rifamycin SV production and the level of transcription of nasB and rifE from U32 and its individual nas mutants in Bennet medium with or without nitrate indicated that nitrate assimilation function encoded by the nas operon played an essential role in the "nitrate stimulated" rifamycin production but had no effect upon the transcription regulation of the primary and secondary metabolic genes related to rifamycin biosynthesis. PMID:21424691

  6. 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.

  7. Aging of the cingulum in the human brain: Preliminary study of a diffusion tensor imaging study.

    PubMed

    Jang, Sung Ho; Kwon, Yong Hyun; Lee, Mi Young; Kim, Jae-Ryong; Seo, Jeong Pyo

    2016-01-01

    The cingulum, a major structure of the limbic system, is closely associated with memory function. In the current study, we investigated aging of the cingulum according to the location of the cingulum in each part of the cingulum after dividing the cingulum into five parts in normal subjects, using DTT parameters (fractional anisotropy (FA) and fiber number (FN)). Ninety healthy subjects (males: 44, females: 46, mean age: 49.0 years; range: 20-78 years) were enrolled in this study. Subjects were categorized according to six groups by age intervals of 10 years; each age group consisted of 15 subjects. The cingulum was divided into five parts (anterior, anterior superior, posterior superior cingulum, posterior, and inferior cingulum). The FA and FN of each part were measured. The FA value indicates the degree of directionality and integrity of white matter microstructures such as axons, myelin, and microtubules, and the FN reflects the total number of fibers in a neural tract. Age-related decline in the FA value may indicate demyelination, and a decline in the number of myelinated fibers of a neural tract can also lead to a decline of the FN. Significant differences in the FA value of the anterior cingulum and anterior superior cingulum, and the FN of the inferior cingulum were observed between age groups (AVOVA, p<0.05). A significant decrease was observed in the FA values of the anterior and anterior superior cingulum of the 60s and 70s age groups compared with those of the 20s and 30s age groups, and in the FN of the inferior cingulum of the 60s and 70s age groups compared with that of the 20s age group (LSD post hoc test, p<0.05). Aging of the cingulum began at both ends of the cingulum in the 20s or 30s, and progressed steadily at a near continuous rate over the lifespan and a significant degenerative aging effect at both ends of the cingulum occurred into the 60s, compared with the 20s or 30s. PMID:26598020

  8. 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.

  9. 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.

  10. 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

  11. 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…

  12. 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.

  13. Aging Instruction Offers New Challenges for the Social Studies Hour.

    ERIC Educational Resources Information Center

    Scott, Joan Norman

    1986-01-01

    Describes a ten and one-half hour upper elementary grade level unit of instruction on the physical, social, and psychological aspects of aging among the elderly. Copies of the course are available from the author. (JDH)

  14. 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…

  15. 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

  16. A multifrequency study of giant radio sources - III. Dynamical age versus spectral age of the lobes of selected sources

    NASA Astrophysics Data System (ADS)

    Machalski, J.; Jamrozy, M.; Saikia, D. J.

    2009-05-01

    The dynamical ages of the opposite lobes of selected giant radio sources are estimated using the DYNAGE algorithm of Machalski et al., and compared with their spectral ages estimated and studied by Jamrozy et al. in Paper II. As expected, the DYNAGE fits give slightly different dynamical ages and other model parameters for the opposite lobes modelled independently of each other, e.g. the age ratios are found to be between ~1.1 and ~1.4. Demanding similar values of the jet power and the radio core density for the same source, we look for a self-consistent solution for the opposite lobes, which results in different density profiles along them. We also show that a departure from the equipartition conditions assumed in the model, justified by X-ray observations of the lobes of some nearby radio galaxies, and a relevant variation of the magnetic field strengths may provide an equalization of the ages of the lobes. A comparison of the dynamical and spectral ages shows that a ratio of the dynamical age to the spectral age of the lobes of investigated giant radio galaxies is between ~1 and ~5, i.e. similar to that found for smaller radio galaxies. To supplement possible causes for this effect already discussed in the literature, such as uncertainty of the assumed parameters of the model, or influence of a possible departure from the energy equipartition assumption, a further two causes are identified and discussed: (i) a difference between the injection spectral indices describing the initial energy distributions of the emitting relativistic particles determined using the DYNAGE algorithm in the dynamical analysis and in the classical spectral-ageing analysis, and (ii) a different influence of the axial ratio of the lobes in the estimation of the dynamical age and the spectral (synchrotron) age. Arguments are given to suggest that DYNAGE can better take account of radiative effects at lower frequencies than the spectral-ageing analysis. The DYNAGE algorithm is especially

  17. The influence of nitrogen and antimony on the optical quality of InNAs(Sb) alloys

    NASA Astrophysics Data System (ADS)

    Latkowska, M.; Baranowski, M.; Linhart, W. M.; Janiaka, F.; Misiewicz, J.; Segercrantz, N.; Tuomisto, F.; Zhuang, Q.; Krier, A.; Kudrawiec, R.

    2016-03-01

    In this work we present detailed studies of the influence of nitrogen and antimony on the optical quality of InNAs(Sb) alloys. We employed photoluminescence, photoreflectance and positron annihilation spectroscopy to reveal the role of antimony and nitrogen on the improvement/degradation of the optical qualities of InNAs(Sb) alloys. A series of 1 μm-thick InNAs(Sb) layers with different nitrogen and antimony concentrations were grown by molecular beam epitaxy. The results of these investigations show that Sb atoms serve as a surfactant which effectively improves the optical quality of InNAsSb alloys. The influence of nitrogen on the optical quality however is not the same as to what has been reported for other dilute nitrides. We observed an improvement of the optical quality for some nitrogen contents. These issues are comprehensively examined and explained.

  18. UAS Integration in the NAS Project - Project Overview

    NASA Technical Reports Server (NTRS)

    Johnson, Chuck

    2011-01-01

    The goal of the UAS integration in the NAS Project is to contribute capabili1es that reduce technical barriers related to the safety and opera1onal challenges associated with enabling routine UAS access to the NAS.

  19. 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

  20. Field studies of the leachability of aged brown coal ash.

    PubMed

    Mudd, G M; Kodikara, J

    2000-09-15

    The environmental management of ash produced from the brown coal power stations of the Latrobe Valley region of Australia has been studied. Current practice consists of slurrying fly and bottom ash, a short distance to an ash disposal pond. However, storage facilities are approaching capacity and alternative ash management strategies are required in the near future. Initially, the ash produced within the power stations is known to possess a large soluble mass, which can leach rapidly to generate a saline leachate with minor trace metal content. After slurrying and deposition within the ash pond, it has been demonstrated that the soluble mass is significantly lower and the ash can be considered as aged or "leached" ash - a more benign waste that meets the criteria for fill material. In order to assess the long-term behaviour of the leached ash and its suitability for co-disposal in engineered sites within overburden dumps, two field cells were constructed and monitored over a period of 1 year. Each cell was 5 x 5 m in area, 3-m deep and HDPE lined with a coarse drainage layer and leachate collection pipe. The first cell only collected natural rainfall and was known as the Dry Cell. The second cell had an external tank of 5000 l installed (200-mm rainfall equivalent) and water was spray-irrigated regularly to simulate higher rainfall and accelerate the leaching process. The cumulative inflow and outflow for each cell has been calculated using a linear relationship and the leachate quality was monitored over time. The results demonstrate that the ash behaves as an unsaturated porous material, with the effect of evaporation through the profile being dominant and controlling the production of leachate. The leachate quality was initially moderately saline in both cells, with the concentration dropping by nearly 95% in the Wet Cell by the end of the field study. The leachate chemistry has been analysed using the PHREEQC geochemical model. The log activity plots of various

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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…

  8. 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.…

  9. 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…

  10. Transcriptional profile reveals altered hepatic lipid and cholesterol metabolism in hyposulfatemic NaS1 null mice.

    PubMed

    Dawson, Paul Anthony; Gardiner, Brooke; Grimmond, Sean; Markovich, Daniel

    2006-07-12

    Sulfate plays an essential role in human growth and development, and its circulating levels are maintained by the renal Na+-SO42- cotransporter, NaS1. We previously generated a NaS1 knockout (Nas1-/-) mouse, an animal model for hyposulfatemia, that exhibits reduced growth and liver abnormalities including hepatomegaly. In this study, we investigated the hepatic gene expression profile of Nas1-/- mice using oligonucleotide microarrays. The mRNA expression levels of 92 genes with known functional roles in metabolism, cell signaling, cell defense, immune response, cell structure, transcription, or protein synthesis were increased (n = 51) or decreased (n = 41) in Nas1-/- mice when compared with Nas1+/+ mice. The most upregulated transcript levels in Nas1-/- mice were found for the sulfotransferase genes, Sult3a1 (approximately 500% increase) and Sult2a2 (100% increase), whereas the metallothionein-1 gene, Mt1, was among the most downregulated genes (70% decrease). Several genes involved in lipid and cholesterol metabolism, including Scd1, Acly, Gpam, Elov16, Acsl5, Mvd, Insig1, and Apoa4, were found to be upregulated (> or = 30% increase) in Nas1-/- mice. In addition, Nas1-/- mice exhibited increased levels of hepatic lipid (approximately 16% increase), serum cholesterol (approximately 20% increase), and low-density lipoprotein (approximately 100% increase) and reduced hepatic glycogen (approximately 50% decrease) levels. In conclusion, these data suggest an altered lipid and cholesterol metabolism in the hyposulfatemic Nas1-/- mouse and provide new insights into the metabolic state of the liver in Nas1-/- mice. PMID:16621889

  11. 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

  12. 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.

  13. Chronic pain, perceived stress, and cellular aging: an exploratory study

    PubMed Central

    2012-01-01

    Background Chronic pain conditions are characterized by significant individual variability complicating the identification of pathophysiological markers. Leukocyte telomere length (TL), a measure of cellular aging, is associated with age-related disease onset, psychosocial stress, and health-related functional decline. Psychosocial stress has been associated with the onset of chronic pain and chronic pain is experienced as a physical and psychosocial stressor. However, the utility of TL as a biological marker reflecting the burden of chronic pain and psychosocial stress has not yet been explored. Findings The relationship between chronic pain, stress, and TL was analyzed in 36 ethnically diverse, older adults, half of whom reported no chronic pain and the other half had chronic knee osteoarthritis (OA) pain. Subjects completed a physical exam, radiographs, health history, and psychosocial questionnaires. Blood samples were collected and TL was measured by quantitative polymerase chain reaction (qPCR). Four groups were identified characterized by pain status and the Perceived Stress Scale scores: 1) no pain/low stress, 2) no pain/high stress, chronic pain/low stress, and 4) chronic pain/high stress. TL differed between the pain/stress groups (p = 0.01), controlling for relevant covariates. Specifically, the chronic pain/high stress group had significantly shorter TL compared to the no pain/low stress group. Age was negatively correlated with TL, particularly in the chronic pain/high stress group (p = 0.03). Conclusions Although preliminary in nature and based on a modest sample size, these findings indicate that cellular aging may be more pronounced in older adults experiencing high levels of perceived stress and chronic pain. PMID:22325162

  14. 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.

  15. 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

  16. Locus of Control, Social Interdependence, Academic Preparation, Age, Study Time, and the Study Skills of College Students.

    ERIC Educational Resources Information Center

    Jones, Craig H.; Slate, John R.; Marini, Irmo

    1995-01-01

    The relationship of students' study skills to their locus of control, social interdependence, academic preparation, age, and study time was studied with 266 college students. Study skills were related to locus of control, age, expected course grade, and study time. The need to address attitudinal and motivational variables in study skills programs…

  17. 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)

  18. 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…

  19. 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…

  20. 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.

  1. 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. PMID:25315784

  2. Fine-pore aeration diffusers: accelerated membrane ageing studies.

    PubMed

    Kaliman, An; Rosso, Diego; Leu, Shao-Yuan; Stenstrom, Michael K

    2008-01-01

    Polymeric membranes are widely used in aeration systems for biological treatment. These membranes may degrade over time and are sensitive to fouling and scaling. Membrane degradation is reflected in a decline in operating performance and higher headloss, resulting in increased energy costs. Mechanical property parameters, such as membrane hardness, Young's modulus, and orifice creep, were used to characterize the performance of membranes over time in operation and to predict their failure. Used diffusers from municipal wastewater treatment plants were collected and tested for efficiency and headloss, and then dissected to facilitate measurements of Young's modulus, hardness, and orifice creep. Higher degree of membrane fouling corresponded consistently with larger orifice creep. A lab-scale membrane ageing simulation was performed with polyurethane and four different ethylene-propylene-diene (EPDM) membrane diffusers by subjecting them to chemical ageing cycles and periodic testing. The results confirmed full-scale plant results and showed the superiority of orifice creep over Young's modulus and hardness in predicting diffuser deterioration. PMID:17706264

  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. Undercontrolled temperament at age 3 predicts disordered gambling at age 32: a longitudinal study of a complete birth cohort.

    PubMed

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

    2012-05-01

    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

  5. 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.

  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. PMID:26643983

  7. Changes in Religiosity in Old Age: An Exploratory Study.

    PubMed

    Cohen-Mansfield, Jiska; Shmotkin, Dov; Hazan, Haim

    2016-09-01

    Changes in religious identity and predictors of change in religiousness are explored in a sample of 1,191 self-respondent Jewish Israeli participants, aged 75 to 94. Data were drawn from two waves of a national survey. Assessments included measures of religious identity, reported change in religiousness, religious practice, functional status, cognitive functioning, and depression. Religious change was reported retrospectively and also examined prospectively. Change in religious identity was reported by approximately 25% of participants. Changes in religiousness were associated with worse functional status and with more depressed affect. Changes in religious identity were associated with a practice that is in the direction of change, even prior to the reported change. Findings raise concerns about the adequacy of social or functional support for persons who wish to continue their previous religious practice. PMID:27284204

  8. 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.

  9. Prevalence of Age-related Macular Degeneration in Old Persons. Age, Gene/Environment Susceptibility Reykjavik Study

    PubMed Central

    Jonasson, Fridbert; Arnarsson, Arsaell; Eiríksdottir, Gudny; Harris, Tamara B.; Launer, Lenore J.; Meuer, Stacy M; Klein, Barbara E; Klein, Ronald; Gudnason, Vilmundur; Cotch, Mary Frances

    2010-01-01

    Purpose To describe the prevalence and signs of early and late age-related macular degeneration (AMD) in an old cohort. Design Population based cohort study Participants We included 5,272 persons 66 years and older, randomly sampled from the Reykjavik area. Methods Fundus images were taken through dilated pupils using a 45°digital camera and were graded for drusen size, type, area, increased retinal pigment, retinal pigment epithelial depigmentation, neovascular lesions and geographic atrophy using the modified Wisconsin Age-Related Maculopathy Grading System. Main outcome measure Age-related macular degenerationin an old cohort. Results Mean age of participants was 76 years. The prevalence of early AMD was 12.4% (95% confidence interval [CI] 11.0–13.9) for those 66–74 year old and 36% (95% CI 30.9–41.1) for those 85 years and older. The prevalence of exudative AMD was 3.3% (95% CI 2.8–3.8) and for pure geographic atrophy 2.4% (95% CI 2.0–2.8). The highest prevalence for late AMD was among those 85 years and older 11.4% (95% CI 8.2–14.5) for exudative AMD and 7.6% (95% CI 4.8–10.4) for pure geographic atrophy. Conclusion Persons 85 years and older have 10-fold higher prevalence of late AMD than those 70–74 years old. The high prevalence of late AMD in the oldest age-group and expected increase of old people in the western world in coming years call for improved preventive measures and novel treatments. PMID:21126770

  10. Age-Related Weakness of Proximal Muscle Studied with Motor Cortical Mapping: A TMS Study

    PubMed Central

    Plow, Ela B.; Varnerin, Nicole; Cunningham, David A.; Janini, Daniel; Bonnett, Corin; Wyant, Alexandria; Hou, Juliet; Siemionow, Vlodek; Wang, Xiao-Feng; Machado, Andre G.; Yue, Guang H.

    2014-01-01

    Aging-related weakness is due in part to degeneration within the central nervous system. However, it is unknown how changes to the representation of corticospinal output in the primary motor cortex (M1) relate to such weakness. Transcranial magnetic stimulation (TMS) is a noninvasive method of cortical stimulation that can map representation of corticospinal output devoted to a muscle. Using TMS, we examined age-related alterations in maps devoted to biceps brachii muscle to determine whether they predicted its age-induced weakness. Forty-seven right-handed subjects participated: 20 young (22.6±0.90 years) and 27 old (74.96±1.35 years). We measured strength as force of elbow flexion and electromyographic activation of biceps brachii during maximum voluntary contraction. Mapping variables included: 1) center of gravity or weighted mean location of corticospinal output, 2) size of map, 3) volume or excitation of corticospinal output, and 4) response density or corticospinal excitation per unit area. Center of gravity was more anterior in old than in young (p<0.001), though there was no significant difference in strength between the age groups. Map size, volume, and response density showed no significant difference between groups. Regardless of age, center of gravity significantly predicted strength (β = −0.34, p = 0.005), while volume adjacent to the core of map predicted voluntary activation of biceps (β = 0.32, p = 0.008). Overall, the anterior shift of the map in older adults may reflect an adaptive change that allowed for the maintenance of strength. Laterally located center of gravity and higher excitation in the region adjacent to the core in weaker individuals could reflect compensatory recruitment of synergistic muscles. Thus, our study substantiates the role of M1 in adapting to aging-related weakness and subtending strength and muscle activation across age groups. Mapping from M1 may offer foundation for an examination of mechanisms

  11. 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

  12. Aging Studies of 2nd Generation BaBar RPCs

    SciTech Connect

    Band, H.R.; /SLAC

    2007-09-25

    The BaBar detector, operating at the PEPII B factory of the Stanford Linear Accelerator Center (SLAC), installed over 200 2nd generation Resistive Plate Chambers (RPCs) in 2002. The streamer rates produced by backgrounds and signals from normal BaBar running vary considerably (0.1- >20 Hz/cm2) depending on the layer and position of the chambers, thus providing a broad spectrum test of RPC performance and aging. The lowest rate chambers have performed very well with stable efficiencies averaging 95%. Other chambers had rate-dependant inefficiencies due to Bakelite drying which were reversed by the introduction of humidified gases. RPC inefficiencies in the highest rate regions of the higher rate chambers have been observed and also found to be rate dependant. The inefficient regions grow with time and have not yet been reduced by operation with humidified input gas. Three of these chambers were converted to avalanche mode operation and display significantly improved efficiencies. The rate of production of HF in the RPC exhaust gases was measured in avalanche and streamer mode RPCs and found to be comparable despite the lower current of the avalanche mode RPCs.

  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. PMID:24799415

  14. 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

  15. Birth characteristics and age at menarche: results from the dietary intervention study in children (DISC)

    PubMed Central

    Ruder, Elizabeth H.; Hartman, Terryl J.; Rovine, Michael J.; Dorgan, Joanne F.

    2011-01-01

    Objective To examine whether birth weight, birth length, and gestational age are individually associated with age at menarche. Methods Analyses were conducted using data from n = 278 female participants in the Dietary Intervention Study in Children (DISC). Age at menarche was prospectively collected as part of the original DISC investigation. DISC participants self-reported birth weight, birth length, and gestational age with assistance from their mothers and other records as part of the DISC06 Follow-up Study at ages 25–29. Linear regression was used to estimate the association of birth characteristics and age at menarche. Results Birth weight was positively associated with age at menarche (p ≤ 0.01) in multiple regression analyses after controlling for BMI-for-age percentile, race and DISC treatment group. No statistically significant relationships were detected between either length or gestational age and age at menarche. Conclusions Higher birth weight may be associated with a modest delay in age at menarche. PMID:20495859

  16. 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…

  17. 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…

  18. 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.

  19. DIETARY CARBOHYDRATE AND PROGRESSION OF AGE-RELATED MACULAR DEGENERATION, A PROSPECTIVE STUDY FROM THE AGE-RELATED EYE DISEASE STUDY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background Cross-sectional studies indicate that diets that provide a higher dietary glycemic index (dGI) are associated with increased risk of age-related macular degeneration (AMD). No prospective studies have addressed this issue. Methods dGI was calculated as the weighted average of GIs from foo...

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

    PubMed

    Conboy, Irina M; Rando, Thomas A

    2012-06-15

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

  1. 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.

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

    PubMed Central

    Conboy, Irina M.; Rando, Thomas A.

    2012-01-01

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

  3. 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…

  4. 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.

  5. 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

  6. 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…

  7. 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…

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

    PubMed Central

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

    2015-01-01

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

  10. 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

  11. 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

  12. Employing biomarkers of healthy ageing for leveraging genetic studies into human longevity.

    PubMed

    Deelen, Joris; van den Akker, Erik B; Trompet, Stella; van Heemst, Diana; Mooijaart, Simon P; Slagboom, P Eline; Beekman, Marian

    2016-09-01

    Genetic studies have thus far identified a limited number of loci associated with human longevity by applying age at death or survival up to advanced ages as phenotype. As an alternative approach, one could first try to identify biomarkers of healthy ageing and the genetic variants associated with these traits and subsequently determine the association of these variants with human longevity. In the present study, we used this approach by testing whether the 35 baseline serum parameters measured in the Leiden Longevity Study (LLS) meet the proposed criteria for a biomarker of healthy ageing. The LLS consists of 421 families with long-lived siblings of European descent, who were recruited together with their offspring and the spouses of the offspring (controls). To test the four criteria for a biomarker of healthy ageing in the LLS, we determined the association of the serum parameters with chronological age, familial longevity, general practitioner-reported general health, and mortality. Out of the 35 serum parameters, we identified glucose, insulin, and triglycerides as biomarkers of healthy ageing, meeting all four criteria in the LLS. We subsequently showed that the genetic variants previously associated with these parameters are significantly enriched in the largest genome-wide association study for human longevity. In conclusion, we showed that biomarkers of healthy ageing can be used to leverage genetic studies into human longevity. We identified several genetic variants influencing the variation in glucose, insulin and triglycerides that contribute to human longevity. PMID:27374409

  13. 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.

  14. 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

  15. 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.

  16. Epitaxial growth and picosecond carrier dynamics of GaInAs/GaInNAs superlattices

    SciTech Connect

    Martin, M.; Mangeney, J.; Travers, L.; Harmand, J. C.; Mauguin, O.; Patriarche, G.

    2009-10-05

    We study GaInAs/GaInNAs superlattice structures grown on InP substrate as potential candidates for photoconductive terahertz devices or saturable absorbers working at 1.55 {mu}m wavelength. The N-rich GaInNAs layers are flat, with no three-dimensional islanding, and act as trapping layers where carriers can recombine rapidly. The carrier lifetime in GaInAs/GaInNAs superlattice was measured for various growth parameters using time-resolved differential transmission experiments at 1.55 {mu}m wavelength. The carrier lifetime is found to depend strongly on N content and can be reduced down to 3.8 ps for samples with 14% of N. The mechanisms involved in the capture process of photocarriers are discussed.

  17. 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.

  18. 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.

  19. 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

  20. 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…

  1. 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…

  2. Age for Enrolling in Full-Time Childcare: A Qualitative Study of Parent and Caregiver Perspectives

    ERIC Educational Resources Information Center

    Undheim, Anne Mari; Drugli, May Britt

    2012-01-01

    The aim of this study was to explore the views of parents and caregivers on the optimal age for enrolment in childcare. The sample consisted of 41 parents of children aged 18 months or less who were in childcare (22 boys and 19 girls), and 34 of their caregivers. Parents and caregivers were interviewed using a semi-structured interview. Both…

  3. 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…

  4. 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

  5. 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…

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

    PubMed Central

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

    2015-01-01

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

  7. 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

  8. 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

  9. 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.

  10. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2015-08-01

    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.

  12. 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

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

    ERIC Educational Resources Information Center

    Sutlive, Vinson H., Ed.; And Others

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

  14. 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

  15. 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.

  16. 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.

  17. Lead Exposure, B Vitamins, and Plasma Homocysteine in Men 55 Years of Age and Older: The VA Normative Aging Study

    PubMed Central

    Park, Sung Kyun; Weisskopf, Marc G.; Tucker, Katherine L.; Sparrow, David; Spiro, Avron; Vokonas, Pantel S.; Nie, Linda Huiling; Hu, Howard; Weuve, Jennifer

    2014-01-01

    Background: Lead (Pb) exposure may influence the plasma concentration of homocysteine, a one-carbon metabolite associated with cardiovascular and neurodegenerative diseases. Little is known about the associations between Pb and homocysteine over time, or the potential influence of dietary factors. Objectives: We examined the longitudinal association of recent and cumulative Pb exposure with homocysteine concentrations and the potential modifying effect of dietary nutrients involved in one-carbon metabolism. Methods: In a subcohort of the Veterans Affairs (VA) Normative Aging Study (1,056 men with 2,301 total observations between 1993 and 2011), we used mixed-effects models to estimate differences in repeated measures of total plasma homocysteine across concentrations of Pb in blood and tibia bone, assessing recent and cumulative Pb exposure, respectively. We also assessed effect modification by dietary intake and plasma concentrations of folate, vitamin B6, and vitamin B12. Results: An interquartile range (IQR) increment in blood Pb (3 μg/dL) was associated with a 6.3% higher homocysteine concentration (95% CI: 4.8, 7.8%). An IQR increment in tibia bone Pb (14 μg/g) was associated with a 3.7% higher homocysteine (95% CI: 1.6, 5.6%), which was attenuated to 1.5% (95% CI: –0.5, 3.6%) after adjusting for blood Pb. For comparison, a 5-year increase in time from baseline was associated with a 5.7% increase in homocysteine (95% CI: 4.3, 7.1%). The association between blood Pb and homocysteine was significantly stronger among participants with estimated dietary intakes of vitamin B6 and folate below (vs. above) the study population medians, which were similar to the U.S. recommended dietary allowance intakes. Conclusions: Pb exposure was positively associated with plasma homocysteine concentration. This association was stronger among men with below-median dietary intakes of vitamins B6 and folate. These findings suggest that increasing intake of folate and B6 might

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

    PubMed

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

    2015-09-01

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

  19. A voxel-based morphometric study of age- and sex-related changes in white matter volume in the normal aging brain

    PubMed Central

    Liu, Haijing; Wang, Lixin; Geng, Zuojun; Zhu, Qingfeng; Song, Zhenhu; Chang, Ruiting; Lv, Huandi

    2016-01-01

    Objective To carry out a cross-sectional study of 187 cognitively normal Chinese adults using the voxel-based morphometry (VBM) approach to delineate age-related changes in the white matter volume of regions of interest in the brain and further analyze their correlation with age. Materials and methods A total of 187 cognitively normal adults were divided into the young, middle, and old age-groups. Conventional magnetic resonance imaging was performed with the Achieva 3.0 T system. Structural images were processed using VBM8 and statistical parametric mapping 8. Regions of interest were obtained by WFU PickAtlas, and all realigned images were spatially normalized. Results Females showed significantly greater total white matter volume than males (t=2.36, P=0.0096, false-discovery rate [FDR] corrected). VBM demonstrated statistically significant age-related differences in white matter volume between the young age-group and the middle age-group (P<0.05, FDR corrected) and between the middle age-group and the old age-group (P<0.05, FDR corrected). No interaction was found between age and sex on white matter volume (P<0.05, FDR corrected). Logistic regression analysis revealed nonlinear correlation between total white matter volume and age (R2=0.124, P<0.001). White matter volume gradually increased before 40 years of age, peaked around 50 years of age, and rapidly declined after 60 years of age. Conclusion Significant age-related differences are present in white matter volume across multiple brain regions during aging. The VBM approach may help differentiate underlying normal neurobiological aging changes of specific brain regions from neurodegenerative impairments. PMID:26966366

  20. 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. PMID:25089853

  1. 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

  2. The relation of midlife diet to healthy aging: a cohort study

    PubMed Central

    Samieri, Cecilia; Sun, Qi; Townsend, Mary K.; Chiuve, Stephanie E.; Okereke, Olivia I.; Willett, Walter C.; Stampfer, Meir; Grodstein, Francine

    2014-01-01

    Background Understanding how to maintain health and well-being in aging populations is critical. Objective To examine the relation of dietary patterns in midlife to the prevalence of healthy aging. Design Cross-sectional observational study. Setting Nurses’ Health Study. Participants 10,670 women with dietary data and no major chronic diseases in 1984–1986, when they were in their late 50’s and early 60s (median age = 59 years); all women provided information on multiple aspects of aging an average 15 years later. Measurements Diet quality in midlife was ascertained using the Alternative Healthy Eating Index-2010 (AHEI-2010) and Alternate Mediterranean diet (A-MeDi) scores, averaged from two food frequency questionnaires (1984–1986). We defined “healthy” vs “usual” aging as of age 70 years; healthy aging was based on survival to 70+ years with maintenance of four health domains - no major chronic diseases, or major impairments in cognitive or physical function or mental health. Results After multivariable adjustment, greater adherence to the AHEI-2010 (upper vs. lower quintile) in midlife was related to 34% (95% CI=9% to 66%, P-trend<0.001) greater odds of healthy versus usual aging. Greater adherence to A-MeDi was related to 46% (95% CI=17% to 83%, P-trend=0.002) greater odds of healthy aging. When the 4 components of healthy aging were analyzed separately, AHEI-2010 and A-MeDi were significantly associated with higher likelihood of no major limitations in physical function and mental health. Limitations Possibility of residual confounding, although we controlled for many confounding factors; bias due to complex patterns of measurement error within diet scores cannot be excluded. Conclusions Better diet quality at midlife appears strongly linked to greater health and well-being among those surviving to older ages. PMID:24189593

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

    PubMed Central

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

    2015-01-01

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

  4. Coronary artery calcium and physical performance as determinants of mortality in older age: the AGES-Reykjavik Study

    PubMed Central

    von Bonsdorff, Mikaela B.; Groffen, Danielle A.I.; Vidal, Jean-Sebastien; Rantanen, Taina; Jonsson, Palmi V.; Garcia, Melissa; Aspelund, Thor; Eiriksdottir, Gudny; Siggeirsdóttir, Kristin; Launer, Lenore; Gudnason, Vilmundur; Harris, Tamara B.

    2013-01-01

    Background Coronary artery calcium (CAC) and physical performance have been shown to be associated with mortality, but it is not clear whether one of them modifies the association. We investigated the association between the extent of CAC and physical performance among older individuals and explored these individual and combined effects on cardiovascular disease (CVD) and non-CVD mortality. Methods We studied 4074 participants of the AGES-Reykjavik Study who were free from coronary heart disease, had a CAC score calculated from computed tomography scans and had data on mobility limitations and gait speed at baseline in 2002-2006 at a mean age of 76 years. Register-based mortality was available until 2009. Results Odds for mobility limitation and slow gait increased according to the extent of CAC. Altogether 645 persons died during the follow-up. High CAC, mobility limitation and slow gait were independent predictors of CVD and non-CVD mortality. The joint effect of CAC and gait speed on non-CVD mortality was synergistic, i.e. compared to those with low CAC and normal gait, the joint effect of high CAC and slow gait exceeded the additive effect of these individual exposures on non-CVD mortality. For CVD mortality, the effect was additive i.e. the joint effect of high CAC and slow gait did not exceed the sum of the individual exposures. Conclusions The extent of CAC and decreased physical performance were independent predictors of mortality and the joint presence of these risk factors increased the risk of non-CVD mortality above and beyond the individual effects. PMID:23414742

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

    PubMed

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

    2014-06-01

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

  6. 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

  7. Three Studies Point to Same Risk Gene for Age-Related Macular Degeneration

    MedlinePlus

    ... macular degeneration Three studies point to same risk gene for age-related macular degeneration NIH-funded research ... in Nature Genetics have converged on the same gene as a rare, but powerful risk factor for ...

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

    PubMed Central

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

    2014-01-01

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

  9. 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.

  10. Heterochronic parabiosis: historical perspective and methodological considerations for studies of aging and longevity.

    PubMed

    Conboy, Michael J; Conboy, Irina M; Rando, Thomas A

    2013-06-01

    Pairing two animals in parabiosis to test for systemic or circulatory factors from one animal affecting the other animal has been used in scientific studies for at least 150 years. These studies have led to advances in fields as diverse as endocrinology, immunology, and oncology. A variation on the technique, heterochronic parabiosis, whereby two animals of different ages are joined to test for systemic regulators of aspects of aging or age-related diseases also has almost a century-long scientific history. In this review, we focus on the history of heterochronic parabiosis, methodological considerations and caveats, and the major advances that have emerged from those studies, including recent advances in our understanding of stem cell aging. PMID:23489470

  11. 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

  12. A stereologic study of the plantar fat pad in young and aged rats

    PubMed Central

    Molligan, Jeremy; Schon, Lew; Zhang, Zijun

    2013-01-01

    Plantar fat pad (PFP) is a tissue structure that absorbs the initial impact of walking and running and ultimately bears body weight at standing. This study was designed to quantify the histomorphological changes of the PFP in aged rats. The most medial PFP was dissected from the hind feet of young rats (4 months old, n = 6) and aged rats (24 months old, n = 6). Histological structure and cellular senescence of PFP were analyzed stereologically and histomorphometrically. Immunohistochemistry of matrix metalloproteinase 9 (MMP9) was also performed on PFP tissue sections. Compared with young rats, the thickness of epidermis, dermis and septa of the PFP were significantly reduced in the aged rats. The total volume of adipose tissue in the PFP of aged rats was only about 65% of that in the young rats. The microvascular density and the number of fat pad units (FPU), a cluster of adipocytes enclosed by elastin septa, in the PFP were unchanged in the aged rats. In the aged rats, the number of adipocytes per FPU was reduced but the number of simple adipocyte clusters, without surrounding septa, was increased. The shift of the types of adipocyte clusters in the aged PFP was accompanied by degradation of elastin fibers and increased expression of MMP9. In conclusion, the PFP, particularly the elastic septa, degenerates significantly in aged rats and this may contribute to the pathology of PFP-related diseases. PMID:24033117

  13. 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.

  14. Laser Gain and Threshold Properties in Compressive-Strained and Lattice-Matched GaInNAs/GaAs Quantum Wells

    SciTech Connect

    Chow, W.W.; Jones, E.D.; Modine, N.A.; Allerman, A.A.; Kurtz, S.R.

    1999-08-04

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

  15. [An outline on the phylogenetic history of metazoa aging phenomenon (to the study of creating a common metazoa aging theory)].

    PubMed

    Boĭko, A G; Labas, Iu A; Gordeeva, A V

    2010-01-01

    The evolution of aging phenomenon in Metazoa was from the very beginning developing from potentially immortal forms to those more prone to aging. Potential immortality is an ancestral feature gradually lost in the course of evolution; at the same time aging and death resulting from aging are not obligatory but highly desirable property of existence of Metazoa with gamogenesis; this is a prerequisite of evolutionary progress as it facilitates species formation processes accelerating phylogenetic groups radiation and thus gives certain outlying evolutionary advantages, namely, accelerating the evolutionary process and the speed of substitution of one species by others. The main principle of aging phenomenon evolution is as follows: it's the substitution of internal factors of death of nonaging Metazoa with external ones programmed in genome. Aging mechanisms add up to limitation of repairing and regeneration capabilities of adult phenotype and/or by extermination of the whole pool of stem cells or its part only. Aging is a holistic process and it can't be drawn down to one of the known cellular processes which in their turn can't be the initial trigger of this process that is programmed in the genome in a vague form (there is no aging program as it is): if at some stage of ontogenesis the reparation mechanism disablement is genetically programmed then this is really the aging phenomenon programming. Mainly full or partial postmitotic design of an organism is programmed, and it is in its turn a factor securing the "harmfulness" of cellular mechanisms, decreasing the physiological potential of an organism with age. By this it increases the chances of mortality among Metazoa species. On the whole the presented material points to the fact that to develop a common aging theory of Metazoa we don't have to substantially replenish the database of biological science, but we need a new understanding of known facts, which determine the initial cognitive position. PMID:20586245

  16. 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

  17. 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…

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

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

  19. Age differences in coping and locus of control: a study of managerial stress in Hong Kong.

    PubMed

    Siu, O; Cooper, C L; Spector, P E; Donald, I

    2001-12-01

    The present study involved data collection from 3 samples of Hong Kong managers to examine mechanisms by which age would relate to work well-being. A total of 634 managers was drawn by random sampling and purposive sampling methods. The results showed that age was positively related to well-being (job satisfaction and mental well-being). Furthermore, older managers reported fewer sources of stress, better coping, and a more internal locus of control. Multiple regression analyses suggested that the relations of age with 2 well-being indicators can be attributed to various combinations of coping, work locus of control, sources of stress, managerial level, and organizational tenure. PMID:11766923

  20. 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),…

  1. 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

  2. Practice and drop-out effects during a 17-year longitudinal study of cognitive aging.

    PubMed

    Rabbitt, Patrick; Diggle, Peter; Holland, Fiona; McInnes, Lynn

    2004-03-01

    Interpretations of longitudinal studies of cognitive aging are misleading unless effects of practice and selective drop-out are considered. A random effects model taking practice and drop-out into account analyzed data from four successive presentations of each of two intelligence tests, two vocabulary tests, and two verbal memory tests during a 17-year longitudinal study of 5,899 community residents whose ages ranged from 49 to 92 years. On intelligence tests, substantial practice effects counteracted true declines observed over 3 to 5 years of aging and remained significant even with intervals of 7 years between successive assessments. Adjustment for practice and drop-out revealed accelerating declines in fluid intelligence and cumulative learning, linear declines in verbal free recall, and no substantial change in vocabulary. Socioeconomic status and basal levels of general fluid ability did not affect rates of decline. After further adjustment for demographics, variability between individuals was seen to increase as the sample aged. PMID:15014091

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

    NASA Astrophysics Data System (ADS)

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

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

  4. 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

  5. Epidemiology of Vestibulo-Ocular Reflex Function: Data from the Baltimore Longitudinal Study of Aging

    PubMed Central

    Li, Carol; Layman, Andrew J.; Geary, Robert; Anson, Eric; Carey, John P.; Ferrucci, Luigi; Agrawal, Yuri

    2014-01-01

    Objective To determine age-related changes in vestibulo-ocular reflex (VOR) function in community-dwelling adults, and evaluate these for associations with demographic characteristics and cardiovascular risk factors. Study Design Cross-sectional analysis within the Baltimore Longitudinal Study of Aging (BLSA), a longitudinal prospective cohort study. Setting Vestibular testing laboratory within an acute care teaching hospital. Patients Community-dwelling adults enrolled in the BLSA. Intervention(s) Horizontal VOR gain measurement using video head-impulse testing and visual acuity testing. Main Outcome Measure(s) VOR gain was calculated as the ratio of eye velocity to head velocity. Demographic and cardiovascular risk factor data were collected through study questionnaires. Results One hundred nine subjects were analyzed with mean age (SD) 69.9 years (14.2), with a range from 26 to 92 years. VOR gain remained stable from age 26 to 79 after which it significantly declined at a rate of 0.012/year (p = 0.033) in adjusted analyses. Individuals aged 80 years or older had a nearly 8-fold increased odds of VOR gain less than 0.80 relative to those aged less than 80 years in multivariate models (prevalence of 13.2% vs. 2.8%; OR 7.79, 95% CI: 1.04–58.38). Otherwise, VOR gain did not differ significantly across demographic or cardiovascular risk groups. Conclusion We report age-related decline in VOR function in individuals aged 80 years and older. Further analyses are in progress to establish the significance of these VOR abnormalities to functional and mobility outcomes in older individuals. PMID:25275869

  6. 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

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

    PubMed Central

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

    2014-01-01

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

  8. 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…

  9. [Psychiatric morbidity in the oldest old. Results of the Berlin Aging Study].

    PubMed

    Helmchen, H; Linden, M; Wernicke, T

    1996-09-01

    An increasing life expectancy leads to a higher number of persons aged 70-84 years and persons aged 85 years and older. Information concerning changes in the spectrum of psychiatric morbidity is rare. The Berlin Aging Study was based on a representative age- and gender-stratified sample (n = 516) of Berlin citizens aged 70-100 years and older. In this inter-disciplinary study, an intensive investigation was carried out by psychologists, sociologists, internists and psychiatrists. This report focuses on subjectively reported complaints (Beschwerdeliste, BL), observed psychopathological symptomatology (Brief Psychiatric Rating Scale, BPRS) and psychiatric diagnoses following the criteria of DSM-III-R (based on the Geriatric Mental State Examination, GMSA). On the self-rating scale (BL) 10% of all persons reported severe subjective complaints, 32% moderate complaints. On the BPRS, 17% showed severe psychopathological symptomatology, 75% at least mild symptoms. Following the criteria of DSM-III-R, 23.5% of all persons had a psychiatric disease, 4.2% a disease of severe intensity. When the DSM-III-R diagnoses "Not Otherwise Specified" (NOS) were included 40.4% of all subjects were diagnosed by the clinical judgement of the psychiatrists to have a psychiatric disease. The most frequent psychiatric diseases were insomnia (18.8%), depression NOS (17.8%) and dementia (13.8%). Dementia showed the well-known age-related increase, whereas no other incidences of psychiatric morbidity were age-related. Persons aged 70-84 years did not differ in the investigated psychiatric variables from persons aged 85 years and older, the only exception being the prevalence of dementia. PMID:8992371

  10. 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

  11. 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

  12. Study of the Physical Condition of Middle-aged Office and Field Workers Aged 50 and Older.

    PubMed

    Yoo, ChanUk; Park, SooHee; Yang, DongJoo; Park, YunHee; Kim, DeokJu; Yang, YeongAe

    2014-10-01

    [Purpose] We investigated the physical condition of middle-aged workers in Korea by job category (office job vs. production job). [Subjects] In total, 3,650 middle-aged workers (production job, n = 2,615; office job, n = 1,035) ≥50 years of age from eight geographical areas were evaluated from 2007 to 2008. [Methods] The subjects' subjective physical condition, exercise status, smoking status, and drinking status were investigated, and precise physical measurements, cardiovascular endurance, muscular strength, muscular endurance, flexibility, reflexes, and reactions were measured. [Results] Subjectively, the physical condition and exercise status of those with office jobs were superior to those of production job workers. Office workers exhibited a higher rate of drinking than production workers, and also had better cardiovascular endurance, muscular strength, muscular endurance, reflexes, and reactions. However, production workers were more flexible than office workers. [Conclusion] Middle-aged production job workers in Korea have poorer overall physical condition than middle-aged office job workers. The physical condition of middle-aged and elderly workers must be managed through various health management programs to secure a productive aging society. PMID:25364116

  13. Study of the Physical Condition of Middle-aged Office and Field Workers Aged 50 and Older

    PubMed Central

    Yoo, ChanUk; Park, SooHee; Yang, DongJoo; Park, YunHee; Kim, DeokJu; Yang, YeongAe

    2014-01-01

    [Purpose] We investigated the physical condition of middle-aged workers in Korea by job category (office job vs. production job). [Subjects] In total, 3,650 middle-aged workers (production job, n = 2,615; office job, n = 1,035) ≥50 years of age from eight geographical areas were evaluated from 2007 to 2008. [Methods] The subjects’ subjective physical condition, exercise status, smoking status, and drinking status were investigated, and precise physical measurements, cardiovascular endurance, muscular strength, muscular endurance, flexibility, reflexes, and reactions were measured. [Results] Subjectively, the physical condition and exercise status of those with office jobs were superior to those of production job workers. Office workers exhibited a higher rate of drinking than production workers, and also had better cardiovascular endurance, muscular strength, muscular endurance, reflexes, and reactions. However, production workers were more flexible than office workers. [Conclusion] Middle-aged production job workers in Korea have poorer overall physical condition than middle-aged office job workers. The physical condition of middle-aged and elderly workers must be managed through various health management programs to secure a productive aging society. PMID:25364116

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

    ERIC Educational Resources Information Center

    Sokolovsky, Jay; Sokolovsky, Joan

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  16. Impaired Design Fluency Is a Marker of Pathological Cognitive Aging; Results from the Korean Longitudinal Study on Health and Aging

    PubMed Central

    Chi, Yeon Kyung; Kim, Tae Hui; Han, Ji Won; Lee, Seok Bum; Park, Joon Hyuk; Lee, Jung Jae; Youn, Jong Chul; Jhoo, Jin Hyung; Lee, Dong Young

    2012-01-01

    Objective We investigated neuropsychological markers that can be used to discriminate pathological cognitive aging from normal cognitive aging. Methods We administered frontal lobe function tests including the Wisconsin Card Sorting Test (WCST), digit span test, lexical fluency test, fixed condition design fluency test, and Trail Making Test B (TMT-B) to 92 individuals with pathological cognitive aging (PCA) and 222 individuals with normal cognitive aging (NCA). We examined the main effects of participants' diagnoses (PCA, NCA) and age (65-69 years old, 70-74 years old and 75 years old or over) on their test performance using multivariate analysis of variance. Results The main effects of both the diagnosis (F=2.860, p=0.002) and the age group (F=2.484, p<0.001) were significant. The PCA group showed lower performance on the backward digit span test (F=14.306, p<0.001), fixed condition design fluency test (F=8.347, p=0.004) and also exhibited perseverative errors in the WCST (F=4.19, p=0.042) compared with the NCA group. The main effect of the diagnosis on the backward digit span test and the fixed condition design fluency test remained significant after Bonferroni correction. The main effect of age remained significant in the TMT-B (F=8.737, p<0.001) after Bonferroni correction. Other test scores were not influenced by diagnosis or age. Conclusion The design fluency task may be a good neuropsychological marker to assess pathological cognitive aging. PMID:22396686

  17. Older adults' perceptions of ageing and their health and functioning: a systematic review of observational studies.

    PubMed

    Warmoth, Krystal; Tarrant, Mark; Abraham, Charles; Lang, Iain A

    2016-07-01

    Many older people perceive ageing negatively, describing it in terms of poor or declining health and functioning. These perceptions may be related to older adults' health. The aim of this review was to synthesise existing research on the relationship between older adults' perceptions of ageing and their health and functioning. A systematic search was conducted of five electronic databases (ASSIA, CINAHL, IBSS, MEDLINE and PsycINFO). Citations within identified reports were also searched. Observational studies were included if they included perceptions of ageing and health-related measures involving participants aged 60 years and older. Study selection, data extraction and quality appraisal were conducted using predefined criteria. Twenty-eight reports met the criteria for inclusion. Older adults' perceptions of ageing were assessed with a variety of measures. Perceptions were related to health and functioning across seven health domains: memory and cognitive performance, physical and physiological performance, medical conditions and outcomes, disability, care-seeking, self-rated health, quality of life and death. How ageing is perceived by older adults is related to their health and functioning in multiple domains. However, higher quality and longitudinal studies are needed to further investigate this relationship. PMID:26527056

  18. 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

  19. 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.

  20. [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

  1. 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

  2. Breathing easy: a prospective study of optimism and pulmonary function in the normative aging study.

    PubMed

    Kubzansky, Laura D; Wright, Rosalind J; Cohen, Sheldon; Weiss, Scott; Rosner, Bernard; Sparrow, David

    2002-01-01

    Although there is good evidence that emotions are associated with chronic airways obstruction, evidence for the influence of psychological factors on the level and decline of pulmonary function is sparse. Optimism has been linked to enhanced well-being, whereas pessimism has been identified as a risk factor for poor physical health. This investigation examines prospectively the effects of optimism versus pessimism on pulmonary function. Data are from the Veterans Administration Normative Aging Study, an ongoing cohort of older men. In 1986, 670 men completed the revised Minnesota Multiphasic Personality Inventory from which we derived the bipolar Revised Optimism-Pessimism Scale. During an average of 8 years of follow-up, an average of 3 pulmonary function exams were obtained. Men with a more optimistic explanatory style had significantly higher levels of forced expiratory volume in 1 sec (FEV1) and forced vital capacity (both p < .01). Interactions between time and optimism suggested that rate of decline in FEV1 over time was slower in men with a more optimistic explanatory style relative to men who were more pessimistic. These data are the first to link optimism with higher levels of pulmonary function and slower rate of pulmonary function decline in older men, a protective effect that is independent of smoking. PMID:12434946

  3. 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…

  4. 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

  5. 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.

  6. A longitudinal study of structural brain network changes with normal aging

    PubMed Central

    Wu, Kai; Taki, Yasuyuki; Sato, Kazunori; Qi, Haochen; Kawashima, Ryuta; Fukuda, Hiroshi

    2013-01-01

    The aim of this study was to investigate age-related changes in the topological organization of structural brain networks by applying a longitudinal design over 6 years. Structural brain networks were derived from measurements of regional gray matter volume and were constructed in age-specific groups from baseline and follow-up scans. The structural brain networks showed economical small-world properties, providing high global and local efficiency for parallel information processing at low connection costs. In the analysis of the global network properties, the local and global efficiency of the baseline scan were significantly lower compared to the follow-up scan. Moreover, the annual rate of change in local and global efficiency showed a positive and negative quadratic correlation with the baseline age, respectively; both curvilinear correlations peaked at approximately the age of 50. In the analysis of the regional nodal properties, significant negative correlations between the annual rate of change in nodal strength and the baseline age were found in the brain regions primarily involved in the visual and motor/control systems, whereas significant positive quadratic correlations were found in the brain regions predominately associated with the default-mode, attention, and memory systems. The results of the longitudinal study are consistent with the findings of our previous cross-sectional study: the structural brain networks develop into a fast distribution from young to middle age (approximately 50 years old) and eventually became a fast localization in the old age. Our findings elucidate the network topology of structural brain networks and its longitudinal changes, thus enhancing the understanding of the underlying physiology of normal aging in the human brain. PMID:23565087

  7. Relation of smoking to the incidence of age-related maculopathy. The Beaver Dam Eye Study.

    PubMed

    Klein, R; Klein, B E; Moss, S E

    1998-01-15

    To date, a number of reports have been published on the relation of cigarette smoking to age-related maculopathy, an important cause of blindness in the United States. However, few studies have examined the relation between smoking and the incidence of age-related maculopathy. In this report, the authors examine this association in persons aged 43-86 years (n = 3,583) at baseline who were participants in the baseline examination and 5-year follow-up of the Beaver Dam Eye Study, Beaver Dam, Wisconsin (1988-1990 and 1993-1995). Exposure data on cigarette smoking were obtained from questions about present and past smoking, duration of smoking, and the number of cigarettes smoked per day. Age-related maculopathy status was determined by grading stereoscopic color fundus photographs using the Wisconsin Age-related Maculopathy Grading System. After controlling for age, sex, vitamin supplement use, and beer consumption, men who smoked greater amounts of cigarettes were more likely to develop early age-related maculopathy (odds ratio (OR) per 10 pack-years smoked = 1.06, 95% confidence interval (CI) 1.00-1.13, p = 0.06) than men who had smoked less. This association was not observed in women. Men (OR = 3.21, 95% CI 1.09-9.45) and women (OR = 2.20, 95% CI 1.04-4.66) who were current smokers at the time of the baseline examination had significantly higher odds of developing large drusen (> or = 250 microns in diameter) after 5 years than those who had never smoked or who quit before the baseline study. Current or past history of cigarette smoking was not related to the incidence of retinal pigment epithelial depigmentation. The authors conclude that smoking appears to be related to the incidence of some lesions associated with early age-related maculopathy. PMID:9456998

  8. Policy Recommendations to VA Leave NAS at Odds with Congress

    ERIC Educational Resources Information Center

    Walsh, John

    1978-01-01

    Describes adverse congressional reaction to a recent National Academy of Sciences (NAS) recommendation that the Veteran's Administration's (VA) health care system be phased into a general health care system. (SL)

  9. 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.

  10. 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.

  11. Identifying the genomic determinants of aging and longevity in human population studies: progress and challenges.

    PubMed

    Deelen, Joris; Beekman, Marian; Capri, Miriam; Franceschi, Claudio; Slagboom, P Eline

    2013-04-01

    Human lifespan variation is mainly determined by environmental factors, whereas the genetic contribution is 25-30% and expected to be polygenic. Two complementary fields go hand in hand in order to unravel the mechanisms of biological aging: genomic and biomarker research. Explorative and candidate gene studies of the human genome by genetic, transcriptomic, and epigenomic approaches have resulted in the identification of a limited number of interesting positive linkage regions, genes, and pathways that contribute to lifespan variation. The possibilities to further exploit these findings are rapidly increasing through the use of novel technologies, such as next-generation sequencing. Genomic research is progressively being integrated with biomarker studies on aging, including the application of (noninvasive) deep phenotyping and omics data - generated using novel technologies - in a wealth of studies in human populations. Hence, these studies may assist in obtaining a more holistic perspective on the role of the genome in aging and lifespan regulation. PMID:23423909

  12. Age effects and sex differences in human brain white matter of young to middle-aged adults: A DTI, NODDI, and q-space study.

    PubMed

    Kodiweera, Chandana; Alexander, Andrew L; Harezlak, Jaroslaw; McAllister, Thomas W; Wu, Yu-Chien

    2016-03-01

    Microstructural changes in human brain white matter of young to middle-aged adults were studied using advanced diffusion Magnetic Resonance Imaging (dMRI). Multiple shell diffusion-weighted data were acquired using the Hybrid Diffusion Imaging (HYDI). The HYDI method is extremely versatile and data were analyzed using Diffusion Tensor Imaging (DTI), Neurite Orientation Dispersion and Density Imaging (NODDI), and q-space imaging approaches. Twenty-four females and 23 males between 18 and 55years of age were included in this study. The impact of age and sex on diffusion metrics were tested using least squares linear regressions in 48 white matter regions of interest (ROIs) across the whole brain and adjusted for multiple comparisons across ROIs. In this study, white matter projections to either the hippocampus or the cerebral cortices were the brain regions most sensitive to aging. Specifically, in this young to middle-aged cohort, aging effects were associated with more dispersion of white matter fibers while the tissue restriction and intra-axonal volume fraction remained relatively stable. The fiber dispersion index of NODDI exhibited the most pronounced sensitivity to aging. In addition, changes of the DTI indices in this aging cohort were correlated mostly with the fiber dispersion index rather than the intracellular volume fraction of NODDI or the q-space measurements. While men and women did not differ in the aging rate, men tend to have higher intra-axonal volume fraction than women. This study demonstrates that advanced dMRI using a HYDI acquisition and compartmental modeling of NODDI can elucidate microstructural alterations that are sensitive to age and sex. Finally, this study provides insight into the relationships between DTI diffusion metrics and advanced diffusion metrics of NODDI model and q-space imaging. PMID:26724777

  13. CARDIOVASCULAR RESPONSES IN THE NORMATIVE AGING STUDY: EXPLORING THE PATHWAYS OF PARTICLE TOXICITY

    EPA Science Inventory

    The NAS cohort has informed us about toxicity of PM2.5, BC, O3 and SO42- on autonomic dysfunction, inflammation, and ...

  14. Paternal Age and Offspring Congenital Heart Defects: A National Cohort Study

    PubMed Central

    Huang, Guo Ying; Olsen, Jørn; Li, Jiong

    2015-01-01

    Paternal age has been associated with offspring congenital heart defects (CHDs), which might be caused by increased mutations in the germ cell line because of cumulated cell replications. Empirical evidences, however, remain inconclusive. Furthermore, it is unknown whether all subtypes of CHDs are affected by paternal age. We aimed to explore the relationship between paternal age and the risk of offspring CHDs and its five common subtypes using national register data in Denmark. A total of 1 893 899 singletons born in Denmark from 1977 to 2008 were included in this national-based cohort study. Cox’s proportion hazards model with robust sandwich estimate option was used to estimate the hazards ratio (95% confidence interval) for the associations between paternal age and all CHDs, as well as subtypes of CHDs (patent ductus arteriosus (PDA), ventricular septal defect (VSD), atrial septal defect (ASD), tetralogy of fallot (TOF) and coarctation of the aorta (CoA)). We did not observe an overall association between paternal age and offspring CHDs. However, compared to the paternal age of 25–29 years, paternal age of older than 45 years was associated with a 69% increased risk of PDA (HR45+ = 1.69, 95%CI:1.17–2.43). We observed similar results when subanalyses were restricted to children born to mothers of 27–30 years old. After taking into consideration of maternal age, our data suggested that advanced paternal age was associated with an increased prevalence of one subtype of offspring congenital heart defects (CHDs), namely patent ductus arteriosus (PDA). PMID:25806788

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

    PubMed

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

    2016-06-01

    A cross-sectional study was conducted to explore the prevalence and severity of health-related complaints perceived by adult males of Hong Kong by using the Hong Kong Traditional Chinese versions of the Aging males' symptoms (AMS) scale and the 5-dimensional and 3-level European Quality of life (EQ-5D-3L) questionnaire. A total of 825 adult males aged 40 years or above were surveyed, and observed that 80% of the population was living with little-to-mild levels of aging symptoms with mean total scores ranged between 26.02 ± 7.91 and 32.99 ± 7.91 in different age groups. Such symptoms were correlated with age, especially for the somato-vegetative and sexual symptoms. The most severe AMS symptoms were observed in the oldest age group at 70 years or above, with 76%, 34% and 70% living with moderate-to-severe levels of somato-vegetative, psychological and sexual symptoms, respectively. The result was highly correlated with the EQ-5D-3L questionnaire. Secondly, the Hong Kong Aging males' symptoms (AMS) scale was shown to have good reliability with test-retest coefficient at 0.79 (ranged 0.66-0.87) and Cronbach's alpha coefficient at 0.88 (ranged 0.70-0.84). In summary, the population of Hong Kong male adults was commonly living with little-to-mild levels of aging symptoms, whereas their severity was correlated with age. PMID:27068128

  16. 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.

  17. Spinal dysraphism. A study of patients over the age of 10 years.

    PubMed

    Yamane, T; Shinoto, A; Kamegaya, M; Shinada, Y

    1991-11-01

    Thirty patients over the age of 10 years, exhibiting cutaneous manifestations on the back suspected to be due to spinal dysraphism, and neurologic deficits, were studied to analyze neurologic appearance. Neurologic deficits appeared by age 5 in 26 patients. No patient complained of low-back pain or sciatica. Paralytic deformities of the lower extremities were divided into four grades for evaluation: A = no deformity, with only urinary disturbance (four cases); B = toe-limited deformity (two cases); C = toe and foot-limited deformity (six cases); D = toe, foot, ankle, and lower limb deformity (18 cases). Patients with slight neurologic disturbance, either Grade A or without urinary disturbance, were seen among the patients who had undergone a release operation by age 2, although neurologic appearance in patients in severe grades was not related to the age at release operation. Also, the release operation was thought to be effective in preventing low-back pain or sciatica. PMID:1750003

  18. 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.

  19. Age-dependent changes in the neural correlates of force modulation: An fMRI study

    PubMed Central

    Ward, Nick S.; Swayne, Orlando B.C.; Newton, Jennifer M.

    2008-01-01

    Functional imaging studies in humans have demonstrated widespread age-related changes in cortical motor networks. However, the relative contribution of cortical regions during motor performance varies not only with age but with task parameters. In this study, we investigated whether motor system activity during a task involving increasingly forceful hand grips was influenced by age. Forty right-handed volunteers underwent functional magnetic brain imaging whilst performing repetitive isometric hand grips with either hand in separate sessions. We found no age-related changes in the average size and shape of the task-related blood oxygen level dependent (BOLD) signal in contralateral primary motor cortex (M1), but did observe reduced ipsilateral M1 deactivation in older subjects (both hands). Furthermore, task-related activity co-varied positively with force output in a number of brain regions, but was less prominent with advancing age in contralateral M1, cingulate sulcus (both hands), sensory and premotor cortices (right hand). These results indicate that a reduced ability to modulate activity in appropriate motor networks when required may contribute to age-related decline in motor performance. PMID:17566608

  20. Effects of aging and food restriction on the trigeminal ganglion: a morphometric study.

    PubMed

    Biedenbach, M A; Kalu, D N; Herbert, D C

    1992-09-01

    A quantitative morphometric study of the rat trigeminal ganglion was conducted to determine the changes that occur with aging. All measurements were tracked from young to old age in two rat groups simultaneously. One group was fed ad libitum, the other was maintained on restricted food intake from 6 weeks on. Immunocytochemical and radioimmunoassay techniques were used to study the neuron group that produces the peptide, CGRP and to compare it with the CGRP-negative neuron group. We observed that in the trigeminal ganglion, soma diameters and nucleus diameters of all neurons, whether CGRP positive or negative, increased modestly with age; so did total ganglion weight. Food restriction delayed, but did not prevent the increases in neuron diameters. No significant changes occurred as a function of age in the total number of neurons per ganglion, the ratio of CGRP positive to CGRP negative neurons and ganglion content of CGRP. Food restriction did not affect the parameters that remained constant with age. These findings are in contrast to the marked inhibitory effect of food restriction on age-related increase in thyroid calcitonin, a hormone that is encoded by the same gene as CGRP. PMID:1434941

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

    PubMed Central

    Chikritzhs, Tanya

    2016-01-01

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

  2. 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.

  3. Early maternal age at first birth is associated with chronic diseases and poor physical performance in older age: cross-sectional analysis from the International Mobility in Aging Study

    PubMed Central

    2014-01-01

    Background Early maternal age at first birth and elevated parity may have long-term consequences for the health of women as they age. Both are known risk factors for obstetrical complications with lifelong associated morbidities. They may also be related to diabetes and cardiovascular disease development. Methods We examine the relationship between early maternal age at first birth, defined as ≤18 years of age, multiparity (>2 births), and poor physical performance (Short Physical Performance Battery ≤8) in community samples of women between 65 and 74 years of age from Canada, Albania, Colombia, and Brazil (N = 1040). Data were collected in 2012 to provide a baseline assessment for a longitudinal cohort called the International Mobility in Aging Study. We used logistic regression and general linear models to analyse the data. Results Early maternal age at first birth is significantly associated with diabetes, chronic lung disease, high blood pressure, and poor physical performance in women at older ages. Parity was not independently associated with chronic conditions and physical performance in older age. After adjustment for study site, age, education, childhood economic adversity and lifetime births, women who gave birth at a young age had 1.75 (95% CI: 1.17 – 2.64) the odds of poor SPPB compared to women who gave birth > 18 years of age. Adjustment for chronic diseases attenuated the association between early first birth and physical performance. Results were weaker in Colombia and Brazil, than Canada and Albania. Conclusions This study provides evidence that adolescent childbirth may increase the risk of developing chronic diseases and physical limitations in older age. Results likely reflect both the biological and social consequences of early childbearing and if the observed relationship is causal, it reinforces the importance of providing contraception and sex education to young women, as the consequences of early pregnancy may be life

  4. Identification of Aggressive Behaviour Tendencies in Junior Age Children: First Stage in a Study of Aggression.

    ERIC Educational Resources Information Center

    Gilmore, C.; And Others

    1985-01-01

    Discusses a study of children aged eight to nine years who were presenting aggressive behavior, with the aim of facilitating intervention at an early stage. Results of questionnaires given to teachers, the children themselves, their peer group, and parents are examined. Difficulties that arose in undertaking this study are explored. (Author/CT)

  5. 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…

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

    ERIC Educational Resources Information Center

    Pfeiffer, Steven; Petscher, Yaacov; Kumtepe, Alper

    2008-01-01

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

  7. Early Childhood Intervention and Educational Attainment: Age 22 Findings from the Chicago Longitudinal Study

    ERIC Educational Resources Information Center

    Ou, Suh-Ruu; Reynolds, Arthur J.

    2006-01-01

    This study investigated whether participation in the Chicago Child-Parent Center (CPC) Preschool Program associated with higher educational attainment (high school completion, highest grade completed, and college attendance) at age 22. The study sample included 1,334 youth (869 in the preschool group and 465 in the comparison group) from the…

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

    ERIC Educational Resources Information Center

    Dorfman, Lorraine T.

    2009-01-01

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

  9. 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…

  10. 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…

  11. Descriptive Study of Multi-Age Grouping for Primary Gifted Students.

    ERIC Educational Resources Information Center

    Hafenstein, Norma Lu; And Others

    This descriptive study used qualitative methods to examine academic and affective components in two primary level multi-aged classrooms at a special school for gifted children. The study methodology included classroom observation, a parent questionnaire, parent interviews, a student questionnaire, student interviews, and teacher interviews. The…

  12. 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...

  13. 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...

  14. 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…

  15. 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…

  16. 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).

  17. 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

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

    PubMed Central

    2011-01-01

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

  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. PMID:25929653

  20. 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. PMID:20426275

  1. 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

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

    PubMed

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

    2016-06-01

    The epigenetic clock, defined as the DNA methylome age (DNAmAge), is a candidate biomarker of ageing. In this study, we aimed to characterize the behaviour of this marker during the human lifespan in more detail using two follow-up cohorts (the Young Finns study, calendar age i.e. cAge range at baseline 15-24 years, 25-year-follow-up, N = 183; The Vitality 90+ study, cAge range at baseline 19-90 years, 4-year-follow-up, N = 48). We also aimed to assess the relationship between DNAmAge estimate and the blood cell distributions, as both of these measures are known to change as a function of age. The subjects' DNAmAges were determined using Horvath's calculator of epigenetic cAge. The estimate of the DNA methylome age acceleration (Δ-cAge-DNAmAge) demonstrated remarkable stability in both cohorts: the individual rank orders of the DNAmAges remained largely unchanged during the follow-ups. The blood cell distributions also demonstrated significant intra-individual correlation between the baseline and follow-up time points. Interestingly, the immunosenescence-associated features (CD8+CD28- and CD4+CD28- cell proportions and the CD4/CD8 cell ratio) were tightly associated with the estimate of the DNA methylome age. In summary, our data demonstrate that the general level of Δ-cAge-DNAmAge is fixed before adulthood and appears to be quite stationary thereafter, even in the oldest-old ages. Moreover, the blood DNAmAge estimate seems to be tightly associated with ageing-associated shifts in blood cell composition, especially with those that are the hallmarks of immunosenescence. Overall, these observations contribute to the understanding of the longitudinal aspects of the DNAmAge estimate. PMID:27300324

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

    PubMed

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

    2016-08-01

    Aging is associated with alterations in the content and patterns of DNA methylation virtually throughout the entire human lifespan. Reasons for these variations are not well understood. However, several lines of evidence suggest that the epigenetic instability in aging may be traced back to the alteration of the expression of DNA methyltransferases. Here, the association of the expression of DNA methyltransferases DNMT1 and DNMT3B with age has been analysed in the context of the MARK-AGE study, a large-scale cross-sectional study of the European general population. Using peripheral blood mononuclear cells, we assessed the variation of DNMT1 and DNMT3B gene expression in more than two thousand age-stratified women and men (35-75 years) recruited across eight European countries. Significant age-related changes were detected for both transcripts. The level of DNMT1 gradually dropped with aging but this was only observed up to the age of 64 years. By contrast, the expression of DNMT3B decreased linearly with increasing age and this association was particularly evident in females. We next attempted to trace the age-related changes of both transcripts to the influence of different variables that have an impact on changes of their expression in the population, including demographics, dietary and health habits, and clinical parameters. Our results indicate that age affects the expression of DNMT1 and DNMT3B as an almost independent variable in respect of all other variables evaluated. PMID:27169697

  5. 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

  6. Maternal Age at Birth and Childhood Type 1 Diabetes: A Pooled Analysis of 30 Observational Studies

    PubMed Central

    Cardwell, Chris R.; Stene, Lars C.; Joner, Geir; Bulsara, Max K.; Cinek, Ondrej; Rosenbauer, Joachim; Ludvigsson, Johnny; Jané, Mireia; Svensson, Jannet; Goldacre, Michael J.; Waldhoer, Thomas; Jarosz-Chobot, Przemysława; Gimeno, Suely G.A.; Chuang, Lee-Ming; Parslow, Roger C.; Wadsworth, Emma J.K.; Chetwynd, Amanda; Pozzilli, Paolo; Brigis, Girts; Urbonaitė, Brone; Šipetić, Sandra; Schober, Edith; Devoti, Gabriele; Ionescu-Tirgoviste, Constantin; de Beaufort, Carine E.; Stoyanov, Denka; Buschard, Karsten; Patterson, Chris C.

    2010-01-01

    OBJECTIVE The aim if the study was to investigate whether children born to older mothers have an increased risk of type 1 diabetes by performing a pooled analysis of previous studies using individual patient data to adjust for recognized confounders. RESEARCH DESIGN AND METHODS Relevant studies published before June 2009 were identified from MEDLINE, Web of Science, and EMBASE. Authors of studies were contacted and asked to provide individual patient data or conduct prespecified analyses. Risk estimates of type 1 diabetes by maternal age were calculated for each study, before and after adjustment for potential confounders. Meta-analysis techniques were used to derive combined odds ratios and to investigate heterogeneity among studies. RESULTS Data were available for 5 cohort and 25 case-control studies, including 14,724 cases of type 1 diabetes. Overall, there was, on average, a 5% (95% CI 2–9) increase in childhood type 1 diabetes odds per 5-year increase in maternal age (P = 0.006), but there was heterogeneity among studies (heterogeneity I2 = 70%). In studies with a low risk of bias, there was a more marked increase in diabetes odds of 10% per 5-year increase in maternal age. Adjustments for potential confounders little altered these estimates. CONCLUSIONS There was evidence of a weak but significant linear increase in the risk of childhood type 1 diabetes across the range of maternal ages, but the magnitude of association varied between studies. A very small percentage of the increase in the incidence of childhood type 1 diabetes in recent years could be explained by increases in maternal age. PMID:19875616

  7. Depression and anxiety among middle-aged women: A community-based study

    PubMed Central

    Bansal, Priya; Chaudhary, Anurag; Soni, R. K.; Sharma, Sarit; Gupta, Vikram Kumar; Kaushal, Pushapindra

    2015-01-01

    Background: Anxiety and depressive disorders constitute a substantial proportion of the global burden of disease and are projected to form the second most common cause of disability by 2020. Objective: To assess the level of depression and anxiety among middle age women and the possible factors behind it. Materials and Methods: A total of 180 women aged 40–60 years were selected by proportionate sampling technique. Age, education, marital status, socioeconomic status, age at marriage, age at menopause, weight and height were noted. Zung-self-rating scales were used for calculating levels of depression and anxiety in these women. The data were analyzed by using statistical software SPSS. Results: The level of syndromal depression and anxiety was found to be 86.7% and 88.9%, respectively. Most of the subjects had the moderate type of depression (49.5%) followed by mild (29.4%) and severe depression (7.8%). While in case of anxiety, most of the subjects (69.4%) had a mild form of anxiety and 17.8% had moderate anxiety level. A significant difference was observed in the level of depression with respect to marital status (P = 0.009) and in the level of anxiety with respect to age (P = 0.021) in the study subjects. On applying logistic regression, none of the factors studied were found to be significant variables for anxiety or depression in the study population. Conclusion: Depression and anxiety are prevalent among the middle-aged women in rural Punjab. Provision of mental health services in this group is essential. PMID:26985419

  8. The Energetic Pathway to Mobility Loss: An Emerging New Framework for Longitudinal Studies on Aging

    PubMed Central

    Schrack, Jennifer A.; Simonsick, Eleanor M.; Ferrucci, Luigi

    2010-01-01

    The capacity to walk independently is a central component of independent living. Numerous large and well designed longitudinal studies have shown that gait speed, a reliable marker of mobility, tends to decline with age and as a consequence of chronic disease. This decline in performance is of utmost importance as slow walking speed is a strong, independent predictor of disability, health care utilization, nursing home admission, and mortality. Based on these robust findings, it has been postulated that the age-associated decline in walking speed is a reliable barometer of the impact of biological aging on health and functional status. Despite the extraordinary prognostic information provided by walking speed, which is often superior to traditional medical information, we have a limited understanding of the mechanisms that underlie age- and disease-related gait speed decline. Identifying the mechanisms that underlie the prognostic value of walking speed should be a central theme in the design of the next generation of longitudinal studies of aging, with appropriate measures introduced, and analytical approaches incorporated. Here, we argue that the decline in customary walking speed with aging and disease is induced by a scarcity of available energy. Based on our work in the Baltimore Longitudinal Study of Aging, we provide examples of measures, operationalized dimensions, and analytical models that may be implemented to tackle this hypothesis. Our main premise is simple: the biochemical processes that maintain life, secure homeostatic equilibrium, and prevent the collapse of health require energy. If energy becomes deficient, adaptive behaviors develop aimed at conserving energy. PMID:21029063

  9. 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

  10. Determining gestational age based on information from the Birth in Brazil study.

    PubMed

    Pereira, Ana Paula Esteves; Leal, Maria do Carmo; da Gama, Silvana Granado Nogueira; Domingues, Rosa Maria Soares Madeira; Schilithz, Arthur Orlando Corrêa; Bastos, Maria Helena

    2014-08-01

    This study aimed at assessing the validity of different measures for estimating gestational age and to propose the creation of an algorithm for gestational age at birth estimates for the Birth in Brazil survey--a study conducted in 2011-2012 with 23,940 postpartum women. We used early ultrasound imaging, performed between 7-20 weeks of gestation, as the reference method. All analyses were performed stratifying by payment of maternity care (public or private). When compared to early ultrasound imaging, we found a substantial intraclass correlation coefficient of ultrasound-based gestational age at admission measure (0.95 and 0.94) and of gestational age reported by postpartum women at interview measure (0.90 and 0.88) for the public and private payment of maternity care, respectively. Last menstrual period-based measures had lower intraclass correlation coefficients than the first two measures evaluated. This study suggests caution when using the last menstrual period as the first measure for estimating gestational age in Brazil, strengthening the use of information obtained from early ultrasound imaging results. PMID:25167191

  11. Pathology assessment is necessary to validate translational endpoints in preclinical aging studies

    PubMed Central

    Ladiges, Warren

    2016-01-01

    The Geropathology Research Network has established a plan to identify and use pathology-based surrogate endpoints for aging intervention in preclinical drug studies to provide a predictable and short-term anti-aging drug response in line with clinical trials. The plan involves pathological assessment of tissues and organs from strains of old mice, by independent pathology groups in a concurrent manner in order to characterize the changes in lesion incidence and severity in response to anti-aging drugs at specific time points. This approach allows for connection with translational endpoints of aging, such as serum factors and physiological parameters, between mice and humans. Preclinical drug testing is a critical component of the plan, designed to shorten testing times from lengthy lifespan studies by comparing lesion grades and composite scores in treated and placebo cohorts at cross-sectional time points. In conclusion, a geropathology-based preclinical testing program is a step toward assuring maximum utilization of translational resources and increasing predictability of efficacy of new or repurposed drugs for clinical aging intervention studies. PMID:27015829

  12. 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

  13. 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

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

    PubMed

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

    2008-08-01

    Fecal specimens were collected from 30 calves from birth to 24 months of age at a dairy farm in Maryland to determine the prevalence and age distribution of Cryptosporidium species/genotypes. After centrifugation to remove debris and concentrate oocysts, specimens were examined by immunofluorescence microscopy and polymerase chain reaction (PCR). Fragments of the SSU-rDNA gene amplified by PCR were purified and PCR products were sequenced. All 30 calves shed Cryptosporidium oocysts at some time during the 24 months of the study. Of 990 specimens, 190 were Cryptosporidium-positive (19.2%). The highest prevalence of infection was at 2 weeks of age when 29 of the 30 calves were excreting oocysts. Prevalence was higher in pre-weaned calves (1-8 weeks of age) (45.8%) than in post-weaned calves (3-12 months of age) (18.5%) and heifers (12-24 months of age) (2.2%). Sequence data for 190 PCR-positive specimens identified: C. parvum, C. bovis, the Cryptosporidium deer-like genotype and C. andersoni, with cumulative prevalences of 100, 80, 60, and 3.3%, respectively. C. parvum constituted 97% of infections in pre-weaned calves but only 4% and 0% of infections in post-weaned calves and heifers, respectively. All C. parvum GP60 nucleotide sequences were subtype IIaA15G2R1. PMID:18565677

  15. Coffee consumption and decreased serum gamma-glutamyltransferase: a study of middle-aged Japanese men.

    PubMed

    Nakanishi, N; Nakamura, K; Nakajima, K; Suzuki, K; Tatara, K

    2000-05-01

    The potential inverse association between coffee intake and serum gamma-glutamyltransferase (GGT) was examined in a cross-sectional study involving 1353 Japanese male office workers aged 35-59 years in Osaka, Japan. Those who had serum aminotransferases exceeding the normal range and/or who had been administered medical care for, or had a past history of, liver disease were excluded. Multiple linear regression analysis and analysis of covariance were used to control for confounding variables (age, body mass index, alcohol use, and cigarette smoking) and to examine possible interactions. From the linear regression analysis, coffee intake was inversely related to serum GGT levels independently of age, body mass index, alcohol intake, and cigarette smoking. All of the latter variables were also independently and positively associated with serum GGT levels. When the interactions between coffee and each of four covariates on serum GGT were evaluated by adding each interaction term to the above regression model, significant negative interactions were observed for age and cigarette smoking. From the analysis of covariance, lower levels of serum GGT associated with coffee consumption were more evident in the older age group and at the higher levels of cigarette smoking. These findings suggest that coffee consumption is inversely related to serum GGT and that coffee may inhibit the inducing effects of aging and possibly of smoking on serum GGT in the liver. PMID:10997828

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

    SciTech Connect

    Hemphill, Geralyn M; Hackenberg, Robert E

    2009-01-01

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

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

    PubMed

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

    2016-01-01

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

  18. 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

  19. Risks and predictors of mild diastolic dysfunction among middle-aged and aged women: a population-based cohort study.

    PubMed

    Wu, J; Yu, S Y; Wo, D; Zhao, M M; Zhang, L J; Li, J

    2016-05-01

    We sought to determine the predictors of primary episodes of mild diastolic dysfunction (DD) in a cohort of women aged >45 years, who had >2 echocardiography from 2009 to 2012. Patients were excluded if they had prior diagnosis of coronary artery disease, heart failure, valvular heart disease or echocardiographic evidence of DD. Mild DD was defined as: left ventricular ejection fraction>50%, E/A ratio<0.75, and E/e'⩽8. Out of the total 758 subjects (age 64.15±7.24 years), 109 (14.3%) had developed mild DD, during a mean followup period of 3 years. Independent predictors of mild DD included: age (P<0.001), history of hypertension (P=0.022), body mass index (BMI) (P<0.001), total triglycerides (TG) (P=0.016), inter ventricular septal thickness (P=0.015) and brachial-ankle pulse wave velocity (baPWV) ⩾16 m s(-1) (P<0.001). E/A ratio was inversely associated with age (r=-0.337, P<0.001), baPWV (r=-0.359, P<0.001), BMI (r=-0.290, P<0.001) and TG (r=-0.255, P<0.001). The Area Under roc Curve for a linear combination of age, BMI, baPWV and TG was 0.738 (95% confidence interval: 0.683-0.804, P<0.001), which was superior to any of the variables taken alone. In summary, many middle-aged or elderly women may develop mild DD within a relatively short period of 3 years. Several subclinical abnormalities and cardiovascular parameters were determined to contribute to the onset of DD. PMID:26310185

  20. 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

  1. Cumulative Lead Exposure and Age at Menopause in the Nurses’ Health Study Cohort

    PubMed Central

    Eum, Ki-Do; Nie, Linda H.; Hu, Howard; Korrick, Susan A.

    2014-01-01

    Background: Early menopause has been associated with many adverse health outcomes, including increased risk of cardiovascular disease morbidity and mortality. Lead has been found to be adversely associated with female reproductive function, but whether exposures experienced by the general population are associated with altered age at menopause has not been explored. Objective: Our goal was to assess the association between cumulative lead exposure and age at natural menopause. Methods: Self-reported menopausal status and bone lead concentration measured with K-shell X-ray fluorescence—a biomarker of cumulative lead exposure—were obtained from 434 women participants in the Nurses’ Health Study. Results: The mean (± SD) age at natural menopause was 50.8 ± 3.6 years. Higher tibia lead level was associated with younger age at menopause. In adjusted analyses, the average age of menopause for women in the highest tertile of tibia lead was 1.21 years younger (95% CI: –2.08, –0.35) than for women in the lowest tertile (p-trend = 0.006). Although the number of cases was small (n = 23), the odds ratio for early menopause (< 45 years of age) was 5.30 (95% CI: 1.42, 19.78) for women in the highest tertile of tibia lead compared with those in the lowest tertile (p-trend = 0.006). There was no association between patella or blood lead and age at menopause. Conclusions: Our results support an association between low-level cumulative lead exposure and an earlier age at menopause. These data suggest that low-level lead exposure may contribute to menopause-related health outcomes in older women through effects on age at menopause. Citation: Eum KD, Weisskopf MG, Nie LH, Hu H, Korrick SA. 2014. Cumulative lead exposure and age at menopause in the Nurses’ Health Study Cohort. Environ Health Perspect 122:229–234; http://dx.doi.org/10.1289/ehp.1206399 PMID:24398113

  2. Paternal Age and General Cognitive Ability—A Cross Sectional Study of Danish Male Conscripts

    PubMed Central

    McGrath, John; Mortensen, Preben Bo; Pedersen, Carsten Bøcker; Ehrenstein, Vera; Petersen, Liselotte

    2013-01-01

    Objectives Offspring of older men have impaired cognitive ability as children, but it is unclear if this impairment persists into adulthood. The main objective of this study was to explore the association between paternal age at offspring birth and general cognitive ability as young adults. Design Population-based cross-sectional study with prospectively collected data on obstetric factors and parental education. Setting Nationwide Danish sample. Participants Male conscripts (n = 169,009). Primary and secondary outcome measures General cognitive ability as assessed by the Børge Priens test score, an intelligence test with components related to logical, verbal, numerical and spatial reasoning. Results We observed an inverse U-shaped association between paternal age and general cognitive ability (slightly lower test scores in the offspring of fathers aged less than 25 years and older than 40 years, compared with fathers aged 25 to 29 years). However, after adjustment for maternal age, parental education and birth order the shape of the association changed. Offspring of fathers younger than 20 still showed slightly lower cognitive ability (-1.11 (95% CI -1.68 to -0.54)), but no significant impairments were identified in the men whose fathers were older than 29 years at the time of their birth (e.g. the mean difference in test score in the offspring of fathers aged 40 to 44 years were -0.03 [95% CI (-0.27 to 0.20)] compared with fathers aged 25 to 29 years). Conclusions We did not find that the offspring of older fathers had impaired cognitive ability as young adults. Whereas, we found a tendency that the offspring of teen fathers have lower cognitive ability. Thus, our results suggest that any potentially deleterious effects of older fathers on general cognitive ability as young adults may be counter-balanced by other potentially beneficial factors. PMID:24116230

  3. 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

  4. 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…

  5. Normative and standardized data for cognitive measures in the Mexican Health and Aging Study

    PubMed Central

    Mejía-Arango, Silvia; Wong, Rebeca; Michaels-Obregón, Alejandra

    2015-01-01

    Objective To describe the cognitive instrument used in the Mexican Health and Aging Study (MHAS) in Mexican individuals aged 60 and over and to provide normative values for the Cross Cultural Cognitive Examination test and its modified versions (CCCE). Materials and methods The CCCE was administered to 5 120 subjects as part of a population-based sample free of neurologic and psychiatric disease from the MHAS 2012 survey. Normative data were generated by age and education for each test in the cognitive instrument as well as for the total cognition score. Pearson correlations and analysis of variance were used to examine the relationship of scores to demographic variables. Results Results present standardized normed scores for eight cognitive domains: orientation, attention, verbal learning memory, verbal recall memory, visuospatial abilities, visual memory, executive function, and numeracy in three education groups within three age groups. Conclusion These highlight the need for population-based norms for the CCCE, which has been used in population-based studies. Demographic factors such as age and education must be considered when interpreting the cognitive measures. PMID:26172239

  6. Age-related degeneration of the fornix in the human brain: a diffusion tensor imaging study.

    PubMed

    Jang, Sung Ho; Cho, Sang-Hyun; Chang, Min Cheol

    2011-02-01

    As a part of the Papez circuit, the fornix carries information on episodic memory. Several diffusion tensor imaging (DTI) studies have reported on changes in the fornix that occur with aging; however, these studies have been controversial. Using DTI, we attempted to investigate age-related changes of the fornix in the human brain. Sixty subjects (30 males, 30 females; mean age, 49.2 years; range, 20-78 years) were recruited. We categorized subjects into three groups, including young (20-39 years), middle-aged (40-59 years), and older (60-79 years) adults. DTIs were acquired using a sensitivity-encoding head coil on a 1.5 T. We divided the whole fornix into three parts (column, body, and crus) and constructed tractography for each part. We measured fractional anisotropy (FA), apparent diffusion coefficient (ADC), and tract number for each part of the fornix. In all three parts of the fornix, the FA value and tract number decreased, whereas ADC value increased with aging. In addition, a linear regression model was fitted to all three DTI parameters in each part of the fornix. Degenerative change of the fornix in the human brain appears to have occurred at a near constant rate from the 20s to the30s throughout the lifespan. PMID:21062216

  7. 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  9. 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

  10. 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

  11. 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…

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

    ERIC Educational Resources Information Center

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

    2006-01-01

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

  13. 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…

  14. 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…

  15. Health-related quality of life in adults with epilepsy: the effect of age, age at onset and duration of epilepsy in a multicentre Italian study

    PubMed Central

    2011-01-01

    Background The potential effect of age-related factors on health-related quality of life (HRQOL) of patients with epilepsy has rarely been analyzed in the literature. Methods We examined this association in a selected population of 815 adults with epilepsy recruited in the context of a multicentre study for the evaluation of Epi-QoL, one of the first Italian epilepsy-specific measures of HRQOL for adults with epilepsy. The Epi-QoL is a 46-item self-administered questionnaire focusing on six domains, which was successfully tested for reproducibility and validity. Ordinary least-squares regression models were used to assess the relationships between age-related factors (patient's age, age at seizure onset, and duration of epilepsy) and overall Epi-QoL score, controlling for the effect of potential confounders. We fitted simple regression models including each age-related factor alone to assess the independent role of each factor on the overall Epi-QoL score. We also fitted multiple regression models including pairs of age-related factors solely, as well as one or two age-related factors together with the same set of confounders. Results Simple regression models showed that age and duration of epilepsy were significant negative predictors of the overall Epi-QoL score: the higher was each age-related factor, the lower was the overall Epi-QoL score; age at onset alone was a nonsignificant predictor of the overall Epi-QoL score. Multiple regression models including two age-related factors solely showed that duration of epilepsy was still a significant negative predictor of the overall Epi-QoL score in both pairwise models, whereas age was a significant negative predictor only in the model including age at onset. Age at onset emerged as a significant positive predictor of the overall Epi-QoL score only in the model including age: the higher was age at onset, the higher was the overall Epi-QoL score. Adjusted regression models including either one or two age

  16. 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…

  17. 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).…

  18. 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.…

  19. 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...

  20. 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…

  1. 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…

  2. 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…

  3. 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…

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

    ERIC Educational Resources Information Center

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

    2010-01-01

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

  5. 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…

  6. 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…

  7. Allostatic Load and Frailty in the Women’s Health and Aging Studies

    PubMed Central

    Szanton, S. L.; Allen, J. K.; Seplaki, C. L.; Bandeen-Roche, K.; Fried, L. P.

    2009-01-01

    Background Frailty involves decrements in many physiologic systems, is prevalent in older ages, and is characterized by increased vulnerability to disability and mortality. It is yet unclear how this geriatric syndrome relates to a preclinical cumulative marker of multisystem dysregulation. The purpose of this study was to evaluate whether allostatic load (AL) was associated with the geriatric syndrome of frailty in older community-dwelling women. Methods We examined the cross-sectional relationship between AL and a validated measure of frailty in the baseline examination of two complementary population-based cohort studies, the Women’s Health and Aging studies (WHAS) I and II. This sample of 728 women had an age range of 70–79. We used ordinal logistic regression to estimate the relationship between AL and frailty controlling for covariates. Results About 10% of women were frail and 46% were prefrail. AL ranged from 0 to 8 with 91% of participants scoring between 0 and 4. Regression models showed that a unit increase in the AL score was associated with increasing levels of frailty (OR = 1.16, 95% CI = 1.04–1.28) controlling for race, age, education, smoking status, and comorbidities. Conclusion This study suggests that frailty is associated with AL. The observed relationship provides some support for the hypothesis that accumulation of physiological dysregulation may be related to the loss of reserve characterized by frailty. PMID:18829589

  8. TESTOSTERONE, DEHYDROEPIANDROSTERONE, AND PHYSICAL PERFORMANCE IN OLDER MEN: RESULTS FROM THE MASSACHUSETTS MALE AGING STUDY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript examines the relationships of total testosterone (T), bioavailable T, dehydroepiandrosterone (DHEA), and DHEA sulfate (DHEAS) to measures of physical performance in a large, population-based, random sample of men. In the most recent wave of the Massachusetts Male Aging Study, measur...

  9. 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…

  10. 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…

  11. 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...

  12. 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…

  13. When Husbands Retire: Men View Their Wives' Satisfaction. Findings from the Normative Aging Study.

    ERIC Educational Resources Information Center

    Ekerdt, David J.; And Others

    The marital relationship is a basic context of retirement, where spouses' separate perceptions of retirement, and of each other's views, are an essential part of the retirement experience. To explore this issue, 297 married men who had been retired for 6 years or less, all participants in the Veterans Administration Normative Aging Study, reported…

  14. 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…

  15. 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.

    2016-05-01

    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.

  16. 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.

  17. Recipient Age and Mortality Risk after Liver Transplantation: A Population-Based Cohort Study

    PubMed Central

    Chen, Hsiu-Pin; Tsai, Yung-Fong; Lin, Jr-Rung; Liu, Fu-Chao; Yu, Huang-Ping

    2016-01-01

    The aim of the present large population-based cohort study is to explore the risk factors of age-related mortality in liver transplant recipients in Taiwan. Basic information and data on medical comorbidities for 2938 patients who received liver transplants between July 1, 1998, and December 31, 2012, were extracted from the National Health Insurance Research Database on the basis of ICD-9-codes. Mortality risks were analyzed after adjusting for preoperative comorbidities and compared among age cohorts. All patients were followed up until the study endpoint or death. This study finally included 2588 adults and 350 children [2068 (70.4%) male and 870 (29.6%) female patients]. The median age at transplantation was 52 (interquartile range, 43–58) years. Recipients were categorized into the following age cohorts: <20 (n = 350, 11.9%), 20–39 (n = 254, 8.6%), 40–59 (n = 1860, 63.3%), and ≥60 (n = 474, 16.1%) years. In the total population, 428 deaths occurred after liver transplantation, and the median follow-up period was 2.85 years (interquartile range, 1.2–5.5 years). Dialysis patients showed the highest risk of mortality irrespective of age. Further, the risk of death increased with an increase in the age at transplantation. Older liver transplant recipients (≥60 years), especially dialysis patients, have a higher mortality rate, possibly because they have more medical comorbidities. Our findings should make clinicians aware of the need for better risk stratification among elderly liver transplantation candidates. PMID:27019189

  18. 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

  19. Age-specific population frequencies of amyloidosis and neurodegeneration among cognitively normal people age 50-89 years: a cross-sectional study

    PubMed Central

    Jack, Clifford R.; Wiste, Heather J.; Weigand, Stephen D.; Rocca, Walter A.; Knopman, David S.; Mielke, Michelle M.; Lowe, Val J.; Senjem, Matthew L.; Gunter, Jeffrey L.; Preboske, Gregory M.; Pankratz, Vernon S.; Vemuri, Prashanthi; Petersen, Ronald C.

    2015-01-01

    Summary Background As treatment of pre-clinical Alzheimer's disease (AD) becomes a focus of therapeutic intervention, observational research studies should recognize the overlap between imaging abnormalities associated with typical aging vs those associated with AD. Our objective was to characterize how typical aging and pre-clinical AD blend together with advancing age in terms of neurodegeneration and b-amyloidosis. Methods We measured age-specific frequencies of amyloidosis and neurodegeneration in 985 cognitively normal subjects age 50 to 89 from a population-based study of cognitive aging. Potential participants were randomly selected from the Olmsted County, Minnesota population by age- and sex-stratification and invited to participate in cognitive evaluations and undergo multimodality imaging. To be eligible for inclusion, subjects must have been judged clinically to have no cognitive impairment and have undergone amyloid PET, FDG PET and MRI. Imaging studies were obtained from March 2006 to December 2013. Amyloid positive/negative status (A+/A−) was determined by amyloid PET using Pittsburgh Compound B. Neurodegeneration positive/negative status (N+/N−) was determined by an AD-signature FDG PET measure and/or hippocampal volume on MRI. We labeled subjects positive or negative for neurodegeneration (FDG PET or MRI) or amyloidosis by using cutpoints defined such that 90% of 75 clinically diagnosed AD dementia subjects were categorized as abnormal. APOE genotype was assessed using DNA extracted from blood. Every individual was assigned to one of four groups: A−N−, A+N−, A−N+, or A+N+. Age specific frequencies of the 4 A/N groups were determined cross-sectionally using multinomial regression models. Associations with APOE ε4 and sex effects were evaluated by including these covariates in the multinomial models. Findings The population frequency of A−N− was 100% (n=985) at age 50 and declined thereafter. The frequency of A+N− increased to a

  20. 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

  1. 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

  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. PMID:25354028

  3. In vitro thermal diffusivity measurements as aging process study in human tooth hard tissues

    NASA Astrophysics Data System (ADS)

    Carvalho, A. P. N.; Dias, D. T.; Bedeschi, V. C.; Nakamura, O.; Oliveira, M. Q.

    2013-11-01

    In the present work, the Open Photoacoustic Cell Technique was used to find effective thermal diffusivity of human tooth hard tissues, a thermal variable of great interest in the biological science, and inorganic materials. The aging process of the tooth enamel and dentin was analyzed through its effective thermal diffusivity. The study in vitro of these samples showed an increase and posterior decrease with aging of the samples. The values found for the enamel and dentin samples, varied from (36-55)×10-4 cm2 s-1 and (20-32)×10-4 cm2 s-1, respectively.

  4. Gay grows up:an interpretive study on aging metaphors and queer identity.

    PubMed

    Fox, Ragan Cooper

    2007-01-01

    This study is based upon qualitative research conducted with the Phoenix chapter of the Prime Timers, a social organization that offers older men in the gay community a space to communicate their general needs and desires. Using data collected through participant observation and informant interviews, the research demonstrates the ways in which the group's affiliates respond to queer sensibilities. The analysis argues that intergenerational communication is fettered by age stereotypes that generate communicative boundaries between young and old members of the gay community. The report then suggests that age-based breakdowns in communication prevalent in the gay community are further advanced by a difference in intergenerational approaches to survival. PMID:17594971

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

    PubMed Central

    2011-01-01

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

  6. Factors Associated with Fatigue among Men Aged 45 and Older: A Cross-Sectional Study

    PubMed Central

    Lin, Wei-Quan; Jing, Meng-Juan; Tang, Jie; Wang, Jia-Ji; Zhang, Hui-Shan; Yuan, Le-Xin; Wang, Pei-Xi

    2015-01-01

    Background and Purpose: Fatigue is one of the most common symptoms reported in several studies; but few studies have concentrated on the male population, especially for the middle-aged and older men who are exposed to greater fatigue risk. The purpose of this study was to explore the prevalence of fatigue and identify the risk factors of fatigue among men aged 45 and older in China. Methods: This study was part of a cross-sectional study on community health in Shunde (Guangdong Province, China). A total sample of 1158 men aged 45 and older were included. Sociodemographic characteristics, health and lifestyle factors and the Chalder Fatigue Scale (CFS) were measured by structured questionnaires through face-to-face interviews. Multivariate logistic regression was applied to determine the risk factors of fatigue. Results: Approximately 30% of participants experienced fatigue. Older age (≥75 years: adjusted OR 3.88, 95% CI 2.09–7.18), single marital status (1.94, 1.04–3.62), unemployed status (1.68, 1.16–2.43), number of self-reported chronic diseases (≥2 chronic diseases: 2.83, 1.86–4.31), number of individuals’ children (≥4 children: 2.35, 1.33–4.15), hospitalization in the last year (1.61, 1.03–2.52) were all significantly associated with increased risk of fatigue, while regular exercise (0.46, 0.32–0.65) was a protective factor against fatigue. Conclusions: Fatigue was usual in males and several factors were associated with the fatigue. These findings may have implication in risk assessment of fatigue and help in developing and implementing targeted interventions in middle-aged and elderly males. PMID:26404346

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

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

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

  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. Aging public services and the position of older women: an Australian case study.

    PubMed

    Colley, Linda

    2014-01-01

    Contemporary labor markets are characterized by both aging of the workforce and the increase in participation of women. At the intersection of these two policy agendas are older women. Governments and employers recognize the importance of attracting and retaining older workers to address skills shortages, but the aging workforce discourse remains largely gender neutral. This research considers the intersection of age and gender in the context of public services, which are large employers of both women and older workers. It focuses on the agencies in an Australian state public service. The research finds that, despite decades of equal opportunity programs, there is still evidence of subtle inequalities and cumulative disadvantage. While the case study agencies employ a large proportion of older women, these women were generally recruited at younger ages and aged within the workforce. Their advancement and development opportunities were also inferior to those of older men. Despite these lesser opportunities, older women are generally very satisfied with their employment, and the employer should explore these residual inequalities if genuinely seeking to attract and retain all older workers. PMID:24713054

  10. 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

  11. A Study on Subsequent Static Aging and Mechanical Properties of Hot-Rolled AA2017

    NASA Astrophysics Data System (ADS)

    Khalili, L.; Serajzadeh, S.

    2014-08-01

    In this work, the effects of rolling parameters, cooling media, and deformation path on mechanical properties and aging behavior of hot-rolled AA2017 were studied. First, hot-rolling experiments were conducted under different working conditions, and the rolled strips were then aged at room temperature for up to 57 days during which hardness and tensile tests were carried out to record the changes in the mechanical properties of the alloy. Furthermore, due to the importance of static recrystallization on subsequent aging behavior, the rate of recrystallization was also computed. To this end, a mathematical model was developed to predict thermomechanical responses during hot rolling using the finite element software, Abaqus/Explicit. Then, a physically-based model was employed for the determination of the kinetics of static recrystallization using the predicted thermomechanical parameters. Finally, the effects of rolling schedule on the mechanical properties and the aging behavior of rolled alloy were evaluated by means of the experimental results and the predictions. The results indicate that natural aging occurs in the hot-rolled alloy, while its influence on the mechanical properties is highly affected by the static recrystallization occurring in the interpass region and/or after rolling on the run-out table.

  12. Stability of Language in Childhood: A Multi-Age, -Domain, -Measure, and -Source Study

    PubMed Central

    Bornstein, Marc H.; Putnick, Diane L.

    2011-01-01

    The stability of language across childhood is traditionally assessed by exploring longitudinal relations between individual language measures. However, language encompasses many domains and varies with different sources (child speech, parental report, experimenter assessment). This study evaluated individual variation in multiple age-appropriate measures of child language derived from multiple sources and stability between their latent variables in 192 young children across more than 2 years. Structural equation modeling demonstrated the loading of multiple measures of child language from different sources on single latent variables of language at ages 20 and 48 months. A large stability coefficient (r = .84) obtained between the 2 language latent variables. This stability obtained even when accounting for family socioeconomic status, maternal verbal intelligence, education, speech, and tendency to respond in a socially desirable fashion, and child social competence. Stability was also equivalent for children in diverse childcare situations and for girls and boys. Across age, from the beginning of language acquisition to just before school entry, aggregating multiple age-appropriate methods and measures at each age and multiple reporters, children show strong stability of individual differences in general language development. PMID:22004343

  13. 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

  14. 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

  15. 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

  16. Prostate Volume Changes Over Time: Results From the Baltimore Longitudinal Study of Aging

    PubMed Central

    Loeb, Stacy; Kettermann, Anna; Carter, H. Ballentine; Ferrucci, Luigi; Metter, E. Jeffrey; Walsh, Patrick C.

    2016-01-01

    Purpose According to a 1944 publication by Swyer benign prostatic hyperplasia develops in some men after age 45 with further prostatic growth whereas in other men prostate size remains stable or decreases with advancing age. Although there is an abundance of literature describing prostatic enlargement in association with benign prostatic hyperplasia, less is known about the phenomenon of prostate atrophy. Materials and Methods In the Baltimore Longitudinal Study of Aging serial pelvic magnetic resonance imaging was performed in men without prostate cancer beginning in 1993. From this population we retrospectively identified 278 men with 2 or more magnetic resonance imaging determined prostate volume measurements to examine differential growth rates in a cohort of community men over time. Results Median age was 58 years and median prostate size was 28 cc at study entry. At a median followup of 4.3 years prostate size increased in 61.9% and remained stable or decreased in 38.1% of men. The median rate of volume change was 0.6 cc per year (range −9.9 to 62.1), corresponding to a median growth rate of 2.5% per year (range −29.2 to 176.4%). During followup 64.6% of men with an initial prostate size less than 40 cc had prostate growth compared to only 50.9% of men with an initial prostate size of 40 cc or greater. Conclusions These results suggest that changes in prostate size are highly variable among aging men. Although benign prostatic hyperplasia is common, a considerable proportion of aging men have a stable or decreasing prostate size. Further research is needed to identify the underlying mechanism for such differences in prostate growth. PMID:19683305

  17. Prevalence of Merkel Cell Polyomavirus in Tehran: An Age-Specific Serological Study

    PubMed Central

    Vahabpour, Rouhollah; Aghasadeghi, Mohammad Reza; Salehi-Vaziri, Mostafa; Mohajel, Nasir; Keyvani, Hossein; Nasimi, Maryam; Esghaei, Maryam; Monavari, Seyed Hamidreza

    2016-01-01

    Background Several new types of polyomavirus have been discovered in recent years mainly because of the recent state-of-the-art detection technologies. Among the polyomaviruses, Merkel cell polyomavirus (MCPyV) has attracted the most attention because of its possible role in the etiology of Merkel cell carcinoma, a rare but lethal form of skin cancer. Objectives This study aimed to determine age-specific seroprevalence of MCPyV in Tehran. Patients and Methods In this cross-sectional study, we collected 440 serum samples from healthy individuals 2 to 78 years of age who visited the Pasteur Institute’s clinic in Tehran, Iran, using a convenience sampling strategy. We developed a virus-like particle-based enzyme-linked immunosorbent assay that uses VP1, the major capsid protein of MCPyV, to detect and quantitate serum antibodies to MCPyV. We compared the prevalence of MCPyV between males and females and across eight age groups. Results A total of 255 (57.9%) of the serum samples were MCPyV positive. The seroprevalence in children under 10 years of age was 25%. The seroprevalence increased to 56% over the next decade of life (10 - 19 years of age). The seroprevalence rate in males and females was 56.1% and 59.7% respectively, and a binary logistic regression showed no significant difference between males and females (P = 0.77). However, the prevalence of MCPyV increased with age (P = 0.012). Conclusions Our results suggest that human exposure to MCPyV occurs throughout life. The MCPyV antibody levels remained high among older adults in our population, consistent with reports from other populations. PMID:27437129

  18. A Population-based Study of Age Inequalities in Access to Palliative Care Among Cancer Patients

    PubMed Central

    Burge, Frederick I.; Lawson, Beverley J.; Johnston, Grace M.; Grunfeld, Eva

    2013-01-01

    Background Inequalities in access to palliative care programs (PCP) by age have been shown to exist in Canada and elsewhere. Few studies have been able to provide greater insight by simultaneously adjusting for multiple demographic, health service, and socio-cultural indicators. Objective To re-examine the relationship between age and registration to specialized community-based PCP programs among cancer patients and identify the multiple indicators contributing to these inequalities. Methods This retrospective, population-based study was a secondary data analysis of linked individual level information extracted from 6 administrative health databases and contextual (neighborhood level) data from provincial and census information. Subjects included all adults who died due to cancer between 1998 and 2003 living within 2 District Health Authorities in the province of Nova Scotia, Canada. The relationship between registration in a PCP and age was examined using hierarchical nonlinear regression modeling techniques. Identification of potential patient and ecologic contributing indicators was guided by Andersen’s conceptual model of health service utilization. Results Overall, 66% of 7511 subjects were registered with a PCP. Older subjects were significantly less likely than those <65 years of age to be registered with a PCP, in particular those aged 85 years and older (adjusted odds ratio: 0.4; 95% confidence interval: 0.3–0.5). Distance to the closest cancer center had a major impact on registration. Conclusions Age continues to be a significant predictor of PCP registration in Nova Scotia even after controlling for the confounding effects of many new demographic, health service, and ecologic indicators. PMID:19300309

  19. 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

  20. 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.

  1. 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

  2. Sugar-sweetened beverage consumption and age at menarche in a prospective study of US girls

    PubMed Central

    Carwile, J.L; Willett, W.C; Spiegelman, D.; Hertzmark, E.; Rich-Edwards, J.; Frazier, A.L; Michels, K.B

    2015-01-01

    STUDY QUESTION Is sugar-sweetened beverage (SSB) consumption associated with age at menarche? SUMMARY ANSWER More frequent SSB consumption was associated with earlier menarche in a population of US girls. WHAT IS KNOWN ALREADY SSB consumption is associated with metabolic changes that could potentially impact menarcheal timing, but direct associations with age at menarche have yet to be investigated. STUDY DESIGN, SIZE, DURATION The Growing up Today Study, a prospective cohort study of 16 875 children of Nurses' Health Study II participants residing in all 50 US states. This analysis followed 5583 girls, aged 9–14 years and premenarcheal at baseline, between 1996 and 2001. During 10 555 person-years of follow-up, 94% (n = 5227) of girls reported their age at menarche, and 3% (n = 159) remained premenarcheal in 2001; 4% (n = 197) of eligible girls were censored, primarily for missing age at menarche. PARTICIPANTS/MATERIALS, SETTING, METHODS Cumulative updated SSB consumption (composed of non-carbonated fruit drinks, sugar-sweetened soda and iced tea) was calculated using annual Youth/Adolescent Food Frequency Questionnaires from 1996 to 1998. Age at menarche was self-reported annually. The association between SSB consumption and age at menarche was assessed using Cox proportional hazards regression. MAIN RESULTS AND THE ROLE OF CHANCE More frequent SSB consumption predicted earlier menarche. At any given age between 9 and 18.5 years, premenarcheal girls who reported consuming >1.5 servings of SSBs per day were, on average, 24% more likely [95% confidence interval (CI): 13, 36%; P-trend: <0.001] to attain menarche in the next month relative to girls consuming ≤2 servings of SSBs weekly, adjusting for potential confounders including height, but not BMI (considered an intermediate). Correspondingly, girls consuming >1.5 SSBs daily had an estimated 2.7-month earlier menarche (95% CI: −4.1, −1.3 months) relative to those consuming ≤2 SSBs weekly. The frequency

  3. 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

  4. 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

  5. Effects of aging on organic aerosol from open biomass burning smoke in aircraft and laboratory studies

    NASA Astrophysics Data System (ADS)

    Cubison, M. J.; Ortega, A. M.; Hayes, P. L.; Farmer, D. K.; Day, D.; Lechner, M. J.; Brune, W. H.; Apel, E.; Diskin, G. S.; Fisher, J. A.; Fuelberg, H. E.; Hecobian, A.; Knapp, D. J.; Mikoviny, T.; Riemer, D.; Sachse, G. W.; Sessions, W.; Weber, R. J.; Weinheimer, A. J.; Wisthaler, A.; Jimenez, J. L.

    2011-12-01

    Biomass burning (BB) is a large source of primary and secondary organic aerosols (POA and SOA). This study addresses the physical and chemical evolution of BB organic aerosols. Firstly, the evolution and lifetime of BB POA and SOA signatures observed with the Aerodyne Aerosol Mass Spectrometer are investigated, focusing on measurements at high-latitudes acquired during the 2008 NASA ARCTAS mission, in comparison to data from other field studies and from laboratory aging experiments. The parameter f60, the ratio of the integrated signal at m/z 60 to the total signal in the organic component mass spectrum, is used as a marker to study the rate of oxidation and fate of the BB POA. A background level of f60~0.3% ± 0.06% for SOA-dominated ambient OA is shown to be an appropriate background level for this tracer. Using also f44 as a tracer for SOA and aged POA and a surrogate of organic O:C, a novel graphical method is presented to characterise the aging of BB plumes. Similar trends of decreasing f60 and increasing f44 with aging are observed in most field and lab studies. At least some very aged BB plumes retain a clear f60 signature. A statistically significant difference in f60 between highly-oxygenated OA of BB and non-BB origin is observed using this tracer, consistent with a substantial contribution of BBOA to the springtime Arctic aerosol burden in 2008. Secondly, a summary is presented of results on the net enhancement of OA with aging of BB plumes, which shows large variability. The estimates of net OA gain range from ΔOA/ΔCO(mass) = -0.01 to ~0.05, with a mean ΔOA/POA ~19%. With these ratios and global inventories of BB CO and POA a global net OA source due to aging of BB plumes of ~8 ± 7 Tg OA yr-1 is estimated, of the order of 5 % of recent total OA source estimates. Further field data following BB plume advection should be a focus of future research in order to better constrain this potentially important contribution to the OA burden.

  6. Effects of aging on organic aerosol from open biomass burning smoke in aircraft and lab studies

    NASA Astrophysics Data System (ADS)

    Cubison, M. J.; Ortega, A. M.; Hayes, P. L.; Farmer, D. K.; Day, D.; Lechner, M. J.; Brune, W. H.; Apel, E.; Diskin, G. S.; Fisher, J. A.; Fuelberg, H. E.; Hecobian, A.; Knapp, D. J.; Mikoviny, T.; Riemer, D.; Sachse, G. W.; Sessions, W.; Weber, R. J.; Weinheimer, A. J.; Wisthaler, A.; Jimenez, J. L.

    2011-04-01

    Biomass burning (BB) is a large source of primary and secondary organic aerosols (POA and SOA). This study addresses the physical and chemical evolution of BB organic aerosols. Firstly, the evolution and lifetime of BB POA and SOA signatures observed with the Aerodyne Aerosol Mass Spectrometer are investigated, focusing on measurements at high-latitudes acquired during the 2008 NASA ARCTAS mission, in comparison to data from other field studies and from laboratory aging experiments. The parameter f60, the ratio of the integrated signal at m/z 60 to the total signal in the organic component mass spectrum, is used as a marker to study the rate of oxidation and fate of the BB POA. A background level of f60~0.3% ±0.06% for SOA-dominated ambient OA is shown to be an appropriate background level for this tracer. Using also f44 as a tracer for SOA and aged POA, a novel graphical method is presented to characterise the aging of BB plumes. Similar trends of decreasing f60 and increasing f44 with aging are observed in most field and lab studies. At least some very aged BB plumes retain a clear f60 signature. A statistically significant difference in f60 between highly-oxygenated OA of BB and non-BB origin is observed using this tracer, consistent with a substantial contribution of BBOA to the springtime Arctic aerosol burden in 2008. Secondly, a summary is presented of results on the net enhancement of OA with aging of BB plumes, which shows large variability. The estimates of net OA gain range from ΔOA/ΔCO(mass) =-0.01 to ~0.07, with a mean ΔOA/POA ~25%. With these ratios and global inventories of BB CO and POA a global net OA source due to aging of BB plumes of ~9 Tg OA yr-1 is estimated, of the order of 5% of recent total OA source estimates. Further field data following BB plume advection should be a focus of future research in order to better constrain this potentially important contribution to the OA burden.

  7. 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

  8. Treating cancer with embryonic stem cells: rationale comes from aging studies.

    PubMed

    Ukraintseva, Svetlana V; Yashin, Anatoly I

    2005-01-01

    In an earlier poster paper (1) we proposed that cancer can be viewed not only as a fatal disease but also as a local aberrant, rejuvenation, in an organism, and this fact can be useful for developing new anti-aging and anti-cancer treatments. In this paper we provide additional evidence from human and experimental animal studies in support of this view. First, we discuss cancer genes as candidate targets for anti-aging interventions. We review examples in which the life of experimental animals has been prolonged in situations of increased activity of proto-oncogenes - or decreased activity of tumor suppressors - in normal (non-cancerous) cells in vivo. Studies of genetic polymorphisms revealed similar effects on longevity in humans. Second, we discuss the possibility of treating cancer with embryonic stem cells. The fact that cancer cells do not, age, means that these cells overcome aging host cells. However, cancer cells can be suppressed by young and quickly proliferating non-cancer cells, such as embryonic stem cells. The grafting of these cells in the tumor environment could be a prospective non-toxic anti-cancer treatment. We discuss recent evidence in support of this view. PMID:15569600

  9. Studies on canine mammary tumours. I. Age, seasonal and breed distribution.

    PubMed

    Boldizsár, H; Szenci, O; Muray, T; Csenki, J

    1992-01-01

    The incidence as well as age, seasonal and breed distribution of canine mammary tumours (n = 521) were studied at the Clinic of Obstetrics and Gynaecology of the University of Veterinary Science, Budapest, between 1985 and 1989. In 39 cases of mammary tumour, blood plasma oestradiol (E2) and progesterone (P) concentrations were also determined. Of all dogs referred to the clinics of the University in 1985, 0.7% had mammary tumour. On the average, 104 +/- 9.3 cases of mammary tumour were recorded at the Clinic of Obstetrics per year. This number did not increase after the Chernobyl atomic reactor catastrophe of 1986. The age distribution of canine mammary tumour found in this study shows good agreement with earlier data of the literature: mammary tumour showed the highest incidence in 10 years old dogs. The incidence of mammary tumour kept increasing with age until the 14th year of life (as expressed in per cent of animals of identical age). The number of mammary tumours was markedly higher in the spring (April-May) and autumn (September). This seasonality was demonstrable in 11 to 16 years old bitches, too. On the basis of the blood plasma E2 and P profiles, 61.5% of the clinically anoestrous animals were found to be cycling. The strikingly high ratio of pulis among dogs with mammary cancer was suggestive of a breed disposition. PMID:1476093

  10. 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. PMID:24997019

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

    ERIC Educational Resources Information Center

    Ross, Randal G.; And Others

    1994-01-01

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

  12. Accounting for Age Uncertainty in Growth Modeling, the Case Study of Yellowfin Tuna (Thunnus albacares) of the Indian Ocean

    PubMed Central

    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 saggital 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

  13. 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

  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. 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

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

    PubMed Central

    Guclu, Ertugrul; Ogutlu, Aziz; Karabay, Oguz

    2016-01-01

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

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

    PubMed Central

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

    2014-01-01

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

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

    PubMed Central

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

    2015-01-01

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

  19. 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.

  20. 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

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

    PubMed

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

    2015-06-01

    Aortic distensibility (AD) decreases with age and increased aortic stiffness is independently associated with adverse cardiovascular outcomes. The association of severe aortic stenosis (AS) with AD in different aortic regions has not been evaluated. Elderly subjects with severe AS and a cohort of patients without AS of similar age were studied. Proximal aortic cross-sectional-area changes during the cardiac cycle were determined using retrospective-ECG-gating on 128-detector row computed-tomography. Using oscillometric-brachial-blood-pressure measurements, the AD at the ascending-aorta (AA), proximal-descending-aorta (PDA) and distal-descending-aorta (DDA) was determined. Linear mixed effects modelling was used to determine the association of age and aortic stenosis on regional AD. 102 patients were evaluated: 36 AS patients (70-85 years), 24 AS patients (>85 years) and 42 patients without AS (9 patients <50 years, 20 patients between 51-70 years and 13 patients 70-85 years). When comparing patients 70-85 years, AA distensibility was significantly lower in those with AS compared to those without AS (0.9 ± 0.9 vs. 1.4 ± 1.1, P = 0.03) while there was no difference in the PDA (1.0 ± 1.1 vs. 1.0 ± 1.2, P = 0.26) and DDA (1.1 ± 1.2 vs. 1.2 ± 0.8, P = 0.97). In patients without AS, AD decreased with age in all aortic regions (P < 0.001). The AA in patients <50 years were the most distensible compared to other aortic regions. There is regional variation in aortic distensibility with aging. Patients with aortic stenosis demonstrated regional differences in aortic distensibility with lower distensibility demonstrated in the proximal ascending aorta compared to an age-matched cohort. PMID:25855464

  2. Blood Telomere Length Attrition and Cancer Development in the Normative Aging Study Cohort

    PubMed Central

    Hou, Lifang; Joyce, Brian Thomas; Gao, Tao; Liu, Lei; Zheng, Yinan; Penedo, Frank J.; Liu, Siran; Zhang, Wei; Bergan, Raymond; Dai, Qi; Vokonas, Pantel; Hoxha, Mirjam; Schwartz, Joel; Baccarelli, Andrea

    2015-01-01

    Background Accelerated telomere shortening may cause cancer via chromosomal instability, making it a potentially useful biomarker. However, publications on blood telomere length (BTL) and cancer are inconsistent. We prospectively examined BTL measures over time and cancer incidence. Methods We included 792 Normative Aging Study participants with 1–4 BTL measurements from 1999 to 2012. We used linear mixed-effects models to examine BTL attrition by cancer status (relative to increasing age and decreasing years pre-diagnosis), Cox models for time-dependent associations, and logistic regression for cancer incidence stratified by years between BTL measurement and diagnosis. Findings Age-related BTL attrition was faster in cancer cases pre-diagnosis than in cancer-free participants (pdifference = 0.017); all participants had similar age-adjusted BTL 8–14 years pre-diagnosis, followed by decelerated attrition in cancer cases resulting in longer BTL three (p = 0.003) and four (p = 0.012) years pre-diagnosis. Longer time-dependent BTL was associated with prostate cancer (HR = 1.79, p = 0.03), and longer BTL measured ≤ 4 years pre-diagnosis with any (OR = 3.27, p < 0.001) and prostate cancers (OR = 6.87, p < 0.001). Interpretation Age-related BTL attrition was faster in cancer cases but their age-adjusted BTL attrition began decelerating as diagnosis approached. This may explain prior inconsistencies and help develop BTL as a cancer detection biomarker. PMID:26288820

  3. Bisphenol A Exposure and Asthma Development in School-Age Children: A Longitudinal Study

    PubMed Central

    Kim, Kyoung-Nam; Kim, Jin Hee; Kwon, Ho-Jang; Hong, Soo-Jong; Kim, Byoung-Ju; Lee, So-Yeon; Hong, Yun-Chul; Bae, Sanghyuk

    2014-01-01

    Background Although the effect of bisphenol A on various health outcomes has been extensively examined, few studies have investigated its effect on asthma. Objective We hypothesized that exposure to bisphenol A in school-age children was associated with wheezing and asthma. Methods Participants included 127 children aged 7–8 years without a previous asthma diagnosis in an elementary school in Seoul, Korea. Three surveys were conducted, each 2 years apart. Bisphenol A concentration was measured at the baseline survey, and PC20, which is defined as the methacholine concentration that induces a decrease in FEV1 of 20% from baseline, was measured at every survey. Associations between bisphenol A concentration at 7–8 years of age and wheezing, asthma, and PC20 at ages up to 11–12 years were examined using generalized estimating equations, a marginal Cox regression model, and a linear mixed model. Results The log-transformed creatinine-adjusted urinary bisphenol A concentration at 7–8 years was positively associated with wheezing (odds ratio, 2.48; 95% confidence interval, 1.15–5.31; P = .02) and asthma (hazard ratio, 2.13; 95% confidence interval, 1.51–3.00; P<.001) at ages up to 11–12 years. Bisphenol A was also negatively associated with PC20 (ß = −2.33; P = .02). When stratified by sex, the association between bisphenol A and asthma remained significant only in girls (hazard ratio, 2.45; 95% confidence interval, 2.18–2.76; P<.001). Conclusion Increased urinary bisphenol A concentrations at 7–8 years old were positively associated with wheezing and asthma and negatively associated with PC20 at ages up to 11–12 years. PMID:25356742

  4. 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.

  5. 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

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

    PubMed Central

    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

  7. Optimism and depression as predictors of physical and mental health functioning: the Normative Aging Study.

    PubMed

    Achat, H; Kawachi, I; Spiro, A; DeMolles, D A; Sparrow, D

    2000-01-01

    Dispositional optimism has been linked in previous studies to better health outcomes. We sought to examine the independent associations of dispositional optimism and depressive symptoms with physical and mental functioning in a cohort of healthy middle-aged and older men. The study was conducted among 659 subjects in the Veterans Administration (VA) Normative Aging Study. Dispositional optimism and depressive symptomatology were measured in 1991 and 1990, respectively, by the Life Orientation Test and the Center for Epidemiologic Studies--Depression Scale (CES-D). The dependent variables, functioning and well-being, were measured in 1992 by the Medical Outcomes Study Short-Form Health Survey (SF-36). In multivariate regression models, optimism was associated with higher levels of general health perceptions, vitality, and mental health, and lower levels of bodily pain, but not to physical functioning, social functioning, or role limitations due to physical or emotional problems. Depressive symptomatology was associated with reduced levels of functioning across all SF-36 domains. The findings for optimism and depression were statistically significant after mutual adjustment in multivariate regression models. Optimism and depression are independent predictors of functional status among aging men. PMID:10962705

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

    ERIC Educational Resources Information Center

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

    1998-01-01

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

  9. Social inequalities in self-rated health by age: Cross-sectional study of 22 457 middle-aged men and women

    PubMed Central

    McFadden, Emily; Luben, Robert; Bingham, Sheila; Wareham, Nicholas; Kinmonth, Ann-Louise; Khaw, Kay-Tee

    2008-01-01

    Background We investigate the association between occupational social class and self-rated health (SRH) at different ages in men and women. Methods Cross sectional population study of 22 457 men and women aged 39–79 years living in the general community in Norfolk, United Kingdom, recruited using general practice age-sex registers in 1993–1997. The relationship between self-rated health and social class was examined using logistic regression, with a poor or moderate rating as the outcome. Results The prevalence of poor or moderate (lower) self-rated health increased with increasing age in both men and women. There was a strong social class gradient: in manual classes, men and women under 50 years of age had a prevalence of lower self-rated health similar to that seen in men and women in non-manual social classes over 70 years old. Even after adjustment for age, educational status, and lifestyle factors (body mass index (BMI), smoking, physical activity and alcohol consumption) there was still strong evidence of a social gradient in self-rated health, with unskilled men and women approximately twice as likely to report lower self-rated health as professionals (ORmen = 2.44 (95%CI 1.69, 3.50); ORwomen = 1.97 (95%CI 1.45, 2.68). Conclusion There was a strong gradient of decreased SRH with age in both men and women. We found a strong cross-sectional association between SRH and social class, which was independent of education and major health related behaviors. The social class differential in SRH was similar with age. Prospective studies to confirm this association should explore social and emotional as well as physical pathways to inequalities in self reported health. PMID:18611263

  10. 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

  11. 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.

  12. Age-related macular degeneration and mortality in community-dwelling elders: The Age, Gene/Environment Susceptibility-Reykjavik Study

    PubMed Central

    Fisher, Diana E.; Jonasson, Fridbert; Eiriksdottir, Gudny; Sigurdsson, Sigurdur; Klein, Ronald; Launer, Lenore J; Gudnason, Vilmundur; Cotch, Mary Frances

    2014-01-01

    Objective To investigate the association between age-related macular degeneration (AMD) and mortality in older persons. Design Population-based prospective cohort study. Participants Participants aged 67–96 years old (43.1% male) enrolled between 2002 and 2006 in the Age, Gene/Environment Susceptibility-Reykjavik Study (AGES). Methods Retinal photography of the macula was digitally acquired and evaluated for the presence of AMD lesions using the Wisconsin Age-Related Maculopathy grading scheme. Mortality was assessed prospectively through 2013 with cause of death available through 2009. The association between AMD and death, due to any cause and specifically, cardiovascular disease (CVD), was examined using Cox proportional hazards regression with age as the time scale, adjusted for significant risk factors and comorbid conditions. To address a violation in the proportional hazards assumption, analyses were stratified into two groups based on the mean age at death (83 years). Main Outcome Measures Mortality from all-causes and cardiovascular disease. Results Among 4910 participants, after a median follow-up period of 8.6 years, 1742 died (35.5%), of whom 614 (35.2%) had signs of AMD at baseline. CVD was the cause of death for 357 people who died before the end of 2009, of whom 144 (40%) had AMD (101 early and 43 late). After considering covariates, including comorbid conditions, having early AMD at any age, or late AMD in individuals under age 83 (n=4179), were not associated with all-cause or CVD mortality. In individuals aged 83 years and older (n=731), late AMD was significantly associated with increased risk of all-cause [hazard ratio (HR): 1.76 (95% confidence interval (CI): 1.20–2.57)] and CVD-related mortality [HR: 2.37 (95% CI: 1.41–3.98)]. In addition to having AMD, older individuals who died were more likely to be male, have low body mass index, impaired cognition, and microalbuminuria. Conclusions Competing risk factors and concomitant conditions

  13. Extended Maternal Age at Birth of Last Child and Women’s Longevity in the Long Life Family Study

    PubMed Central

    Sun, Fangui; Sebastiani, Paola; Schupf, Nicole; Bae, Harold; Andersen, Stacy L; McIntosh, Avery; Abel, Haley; Elo, Irma T.; Perls, Thomas T.

    2014-01-01

    Objective This study investigated the association between maternal ages at birth of last child and the likelihood of survival to advanced ages. Methods A nested case-control study using Long Life Family Study (LLFS) data. Three hundred and eleven women who survived past the oldest 5th percentile of survival according to birth cohort matched life tables were identified as cases and 151 women who died at ages younger than the top 5th percentile of survival were identified as controls. A Bayesian mixed-effect logistic regression model was used to estimate the association between maternal age at birth of last child and exceptional longevity among these 462 women. Results A significant association for later maternal age was found whereby women who had their last child beyond the age of 33 years had twice the odds of survival to the top 5th percentile of survival of their birth cohorts compared to women who had their last child by age 29 (OR=2.08, 95%CI 1.13; 3.92 for age between 33 and 37 years and OR=1.92, 95% CI 1.03; 3.68 for older age). Conclusion The study supports the findings from other studies demonstrating a positive association between older maternal age and greater odds of the mother surviving to unusually old age. PMID:24977462

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

    PubMed

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

    2016-04-14

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

  15. Rates of Complications and Mortality in Older Diabetes Patients: The Diabetes and Aging Study

    PubMed Central

    Huang, Elbert S.; Laiteerapong, Neda; Liu, Jennifer Y.; John, Priya M.; Moffet, Howard H.; Karter, Andrew J.

    2014-01-01

    Importance In the coming decades, the population of older adults with diabetes is expected to grow substantially. Understanding the clinical course of diabetes in this population is critical for establishing evidence-based clinical practice recommendations, research priorities, allocating resources, and setting health policies. Objective Contrast rates of diabetes complications and mortality across age and diabetes duration categories. Design, Setting, Participants This cohort study (2004–2010) included 72,310 older (≥60 years of age) patients with type 2 diabetes enrolled in a large, integrated healthcare delivery system. Incidence densities (events per 1000 person-years (pys)) were calculated for each age category (60s, 70s, 80+ years) and duration of diabetes (shorter: 0–9 years vs. longer: 10+ years). Main Outcome Measures Incident acute hyperglycemic events, acute hypoglycemic events (hypoglycemia), microvascular complications [end-stage renal disease (ESRD), peripheral vascular disease, lower extremity amputation, advanced eye disease], cardiovascular complications [coronary artery disease (CAD), cerebrovascular disease (CVD), congestive heart failure (CHF)], and all-cause mortality. Results Among older adults with diabetes of short duration, cardiovascular complications followed by hypoglycemia were the most common non-fatal complications. For example, among 70–79 year olds with short duration of diabetes, CAD and hypoglycemia rates were higher (11.5 and 5.0/1000 pys respectively), compared to ESRD (2.6/1000), amputation (1.3/1000), and acute hyperglycemic events (0.8/1000). We observed a similar pattern among subjects in the same age group with long diabetes duration where CAD and hypoglycemia had some of the highest incidence rates (19.0 and 15.9 /1000 pys respectively), compared to ESRD (7.6/1000), amputation (4.3/1000), and acute hyperglycemic events (1.8/1000). For a given age group, rates of each outcome, particularly hypoglycemia and

  16. 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. PMID:21491139

  17. Prevalence of Airflow Obstruction in Nonsmoking Older Individuals Using Different Spirometric Criteria: The AGES Reykjavik Study

    PubMed Central

    Runarsdottir, Solrun Bjork; Gudmundsson, Gunnar; Aspelund, Thor; Harris, Tamara B.; Launer, Lenore J.; Gudnason, Vilmundur; Gislason, Thorarinn

    2016-01-01

    Background The prevalence and characteristics of airway obstruction in older individuals varies widely with the definition used. We used a random sample of never smoking older population in Iceland to compare the prevalence and clinical profile of subjects diagnosed with Chronic Obstructive Pulmonary Disease (COPD) based on different spirometric criteria. Material and methods The study uses data from the Age, Gene/Environment Susceptibility–Reykjavik Study, comprising survivors from the Reykjavik Study. Procedures included standardized questionnaires and pre-bronchodilator spirometry for measurement of forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). Results Total of 495 individuals (150 men and 345 women) met study criteria. Mean age 77 years (range 66–92 years) using fixed ratio (FEV1/FVC < 70%) up to 29% of the population were diagnosed with COPD Stage I. The prevalence of COPD increased with age. Only 7 among 495 (1.4%) were diagnosed with COPD using FEV1/FVC LLN and FEV1 LLN. Conclusion Application of the GOLD criteria for diagnosis of COPD in older lifelong never smoking subjects identifies a substantial number of non-symptomatic subjects as having COPD. If airway obstruction is defined by FEV1/FVC and FEV1 being below the LLN using appropriate reference equations, only very few non-smoking older individuals fulfill the criteria for COPD. PMID:23875743

  18. 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

  19. Placental aging and oxidation damage in a tissue micro-array model: an immunohistochemistry study.

    PubMed

    Londero, Ambrogio P; Orsaria, Maria; Marzinotto, Stefania; Grassi, Tiziana; Fruscalzo, Arrigo; Calcagno, Angelo; Bertozzi, Serena; Nardini, Nastassia; Stella, Enrica; Lellé, Ralph J; Driul, Lorenza; Tell, Gianluca; Mariuzzi, Laura

    2016-08-01

    To evaluate the expression of markers correlated with cellular senescence and DNA damage (8-hydroxy-2'-deoxy-guanosine (8-OHdG), p53, p21, APE1/Ref-1 (APE1), interleukin (IL-6 and IL-8) in placentas from healthy and pathologic pregnancies. This retrospective study considered a placental tissue micro-array containing 92 controls from different gestational ages and 158 pathological cases including preeclampsia (PE), HELLP syndrome (hemolysis, elevated liver enzymes, low platelet count), small for gestational age (SGA) fetuses, and intrauterine growth restriction (IUGR) occurring at different gestational ages. In this study, we demonstrated a significant influence of gestational age on the expression in the trophoblast of 8-OHdG, p53, p21, APE1, and IL-6. In placentas of cases affected by PE, HELLP, or IUGR, there was an increased expression of 8-OHdG, p53, APE1, and IL-6 compared to controls (only IL-8 was significantly decreased in cases). In both groups of pathology between 22- and 34-week gestation and after 34-week gestation, APE1 levels were higher in the trophoblast of women affected by hypertensive disorders of pregnancy than women carrying an IUGR fetus. The cytoplasmic expression of 8-OHdG was increased in placentas in IUGR cases compared to PE or HELLP pregnancies. In cases after 34-week gestation, p21 was higher in SGA and IUGR than in controls and late PE. Moreover, p53 was increased after 34-week gestation in IUGR pregnancies. Placentas from pathological pregnancies had an altered expression of 8-OHdG, p53, p21, APE1, IL-6, and IL-8. The alterations of intracellular pathways involving these elements may be the cause or the consequence of placental dysfunction, but in any case reflect an impaired placental function, possibly due to increased aging velocity in pathologic cases. PMID:27106773

  20. 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

  1. New BPD predicts lung function at school age: Follow-up study and meta-analysis.

    PubMed

    Ronkainen, Eveliina; Dunder, Teija; Peltoniemi, Outi; Kaukola, Tuula; Marttila, Riitta; Hallman, Mikko

    2015-11-01

    New treatment practices have improved survival of preterm infants and decreased airway pathology in bronchopulmonary dysplasia (BPD). Our aim was to investigate whether preterm birth, BPD, and the severity of BPD predict lung function in school children that are born in surfactant era. We studied pulmonary function of 88 school-aged children born very preterm (gestational age <32 weeks) and paired them with 88 age- and sex-matched controls born at term. Spirometry and diffusion capacity were recorded. We also performed a meta-analysis covering the era of antenatal corticosteroid and surfactant treatment. BPD was defined as oxygen dependence for ≥ 28 days and it was severity-graded by oxygen requirement at 36 weeks postmenstrual age (mild, none; moderate, FiO2 = 0.22-0.29; severe, FiO2 ≥ 0.30). Preterm children had lower forced expiratory volume in 1 sec (FEV1 ) 86.4 ± 11.8 versus 94.9 ± 10.1 (mean % predicted ± SD; P < 0.001), and lower diffusion capacity (DLCO) 87.6 ± 13.9 versus 93.7 ± 12.0 (P = 0.005) compared with term controls. BPD group differed in both FEV1 (P = 0.037) and DLCO (P = 0.018) from those without BPD. For meta-analysis, search identified 210 articles. Together with present results, six articles met the inclusion criteria. FEV1 of no BPD, all BPD, and moderate to severe BPD groups differed from that in term controls by -7.4, -10.5, and -17.8%, respectively. According to meta-analysis and follow-up study, the adverse effects of prematurity on pulmonary function are still detectable in school-age. BPD was associated with reductions in both diffusion capacity and spirometry. New interventions are required to document a further decrease in the life-long consequences of prematurity. PMID:25589379

  2. 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

  3. 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

  4. Feasibility of multi-site clinical structural neuroimaging studies of aging using legacy data.

    PubMed

    Fennema-Notestine, Christine; Gamst, Anthony C; Quinn, Brian T; Pacheco, Jenni; Jernigan, Terry L; Thal, Leon; Buckner, Randy; Killiany, Ron; Blacker, Deborah; Dale, Anders M; Fischl, Bruce; Dickerson, Brad; Gollub, Randy L

    2007-01-01

    The application of advances in biomedical computing to medical imaging research is enabling scientists to conduct quantitative clinical imaging studies using data collected across multiple sites to test new hypotheses on larger cohorts, increasing the power to detect subtle effects. Given that many research groups have valuable existing (legacy) data, one goal of the Morphometry Biomedical Informatics Research Network (BIRN) Testbed is to assess the feasibility of pooled analyses of legacy structural neuroimaging data in normal aging and Alzheimer's disease. The present study examined whether such data could be meaningfully reanalyzed as a larger combined data set by using rigorous data curation, image analysis, and statistical modeling methods; in this case, to test the hypothesis that hippocampal volume decreases with age and to investigate findings of hippocampal asymmetry. This report describes our work with legacy T1-weighted magnetic resonance (MR) and demographic data related to normal aging that have been shared through the BIRN by three research sites. Results suggest that, in the present application, legacy MR data from multiple sites can be pooled to investigate questions of scientific interest. In particular, statistical analyses suggested that a mixed-effects model employing site as a random effect best fits the data, accounting for site-specific effects while taking advantage of expected comparability of age-related effects. In the combined sample from three sites, significant age-related decline of hippocampal volume and right-dominant hippocampal asymmetry were detected in healthy elderly controls. These expected findings support the feasibility of combining legacy data to investigate novel scientific questions. PMID:17999200

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

    PubMed

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

    2016-06-01

    Healthy aging is considered as the core issue of aging population. Centenarians are a symbol of healthy aging. Concentration of elements in hair is an indicator of micronutrient status, which can affect the human health. In the present study, we investigated element concentrations in the scalp hair of 255 healthy centenarians from Hainan Island, China. The pattern of intergenerational transmission of elements and the effects of confounders such as sex, age, education level, smoking habits, alcohol intake, and frequency of hospitalization on hair element concentrations were assessed. For most elements, the load in hair increased significantly through intergenerational transmission (i.e., centenarians < children < grandchildren). Our results also demonstrated that female centenarians had significantly higher concentrations of Ca, Mg, Mn, Se, and Sr but lower levels of Cr and P. The Mn level was statistically significantly lower in the primary studies group. Alcohol intake was positively associated with Cd and Na levels, whereas smoking habits showed no significant effect on all the elements. Furthermore, the frequency of hospitalization was significantly positively associated with Cd, Cu, and Pb concentration. Moreover, our analysis suggested that adequate concentrations of Fe and Se might increase the life span of centenarians, whereas excessive concentrations of P and Pb were harmful to health and reduced life span. These results imply that element concentrations could be manipulated as a therapeutic modality in geriatric disease. They might also provide reference values for diseased subjects, allowing improved diagnoses and more effective therapies, which might support effective policies on health and aging. PMID:26228349

  6. Communication & Aging.

    ERIC Educational Resources Information Center

    Arnold, William E.

    This extensive bibliography contains more than 1,800 entries about communication and aging. The citations include journal articles, unpublished papers, speeches, dissertations, research studies, and books that relate aging and the aged to a variety of topics, including the following: physiological deterioration, socialization, political…

  7. 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.

  8. Effect of patients' age on management of acute intracranial haematoma: prospective national study

    PubMed Central

    Munro, Philip T; Smith, Rik D; Parke, Timothy R J

    2002-01-01

    Objective To determine whether the management of head injuries differs between patients aged ⩾65 years and those <65. Design Prospective observational national study over four years. Setting 25 Scottish hospitals that admit trauma patients. Participants 527 trauma patients with extradural or acute subdural haematomas. Main outcome measures Time to cranial computed tomography in the first hospital attended, rates of transfer to neurosurgical care, rates of neurosurgical intervention, length of time to operation, and mortality in inpatients in the three months after admission. Results Patients aged ⩾65 years had lower survival rates than patients <65 years. Rates were 15/18 (83%) v 165/167 (99%) for extradural haematoma (P=0.007) and 61/93 (66%) v 229/249 (92%) for acute subdural haematoma (P<0.001). Older patients were less likely to be transferred to specialist neurosurgical care (10 (56%) v 142 (85%) for extradural haematoma (P=0.005) and 56 (60%) v 192 (77%) for subdural haematoma (P=0.004)). There was no significant difference between age groups in the incidence of neurosurgical interventions in patients who were transferred. Logistic regression analysis showed that age had a significant independent effect on transfer and on survival. Older patients had higher rates of coexisting medical conditions than younger patients, but when severity of injury, initial physiological status at presentation, or previous health were controlled for in a log linear analysis, transfer rates were still lower in older patients than in younger patients (P<0.001). Conclusions Compared with those aged under 65 years, people aged 65 and over have a worse prognosis after head injury complicated by intracranial haematoma. The decision to transfer such patients to neurosurgical care seems to be biased against older patients. What is already known on this topicOlder patients with acute intracranial haematomas have significantly higher mortality and poorer functional outcome than

  9. 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

  10. [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

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

    PubMed Central

    Smith, Tanyka K.

    2015-01-01

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

  12. 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

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

    PubMed

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

    2015-07-01

    Despite increasing evidence of the relationship between neighborhood cohesion and depressive mood, little is known about this longitudinal association in old age. This study examined the association between perceived neighborhood cohesion and depressive mood and the stress-buffering effect of perceived neighborhood cohesion on depressive mood among older Japanese people using the 2010 (baseline) and 2012 (follow-up) Hatoyama Cohort Study datasets. We analyzed 655 participants aged 65-84 at baseline. Although perceived neighborhood cohesion at baseline was not associated with depressive mood at follow-up, high neighborhood cohesion partially offset the deleterious effect of anticipated daily stressors on depressive mood. This effect was stronger for long-term residents of the neighborhood. Interventions to strengthen neighborhood cohesion may help reduce the deleterious effect of stressors on older residents' depressive mood. PMID:26113436

  14. 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.

  15. 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.

  16. Do hassles and uplifts trajectories predict mortality? Longitudinal findings from the VA Normative Aging Study.

    PubMed

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

    2016-06-01

    We examined whether longitudinal patterns of hassles and uplifts trajectories predicted mortality, using a sample of 1315 men from the VA Normative Aging Study (mean age = 65.31, SD = 7.6). In prior work, we identified different trajectory classes of hassles and uplifts exposure and intensity scores over a period of 16 years. In this study, we used the probabilities of these exposure and intensity class memberships to examine their ability to predict mortality. Men with higher probabilities of high hassle intensity trajectory class and high uplift intensity class had higher mortality risks. In a model combining the probabilities of hassle and uplift intensities, the probability of high intensity hassle class membership significantly increased the risk of mortality. This suggests that appraisals of hassles intensity are better predictors of mortality than simple exposure measures, and that uplifts have no independent effects. PMID:26721518

  17. Lead Exposure and Tremor among Older Men: The VA Normative Aging Study

    PubMed Central

    Power, Melinda C.; Sparrow, David; Spiro, Avron; Hu, Howard; Louis, Elan D.; Weisskopf, Marc G.

    2015-01-01

    Background: Tremor is one of the most common neurological signs, yet its etiology is poorly understood. Case–control studies suggest an association between blood lead and essential tremor, and that this association is modified by polymorphisms in the δ-aminolevulinic acid dehydrogenase (ALAD) gene. Objective: We aimed to examine the relationship between lead and tremor, including modification by ALAD, in a prospective cohort study, using both blood lead and bone lead—a biomarker of cumulative lead exposure. Methods: We measured tibia (n = 670) and patella (n = 672) bone lead and blood lead (n = 807) among older men (age range, 50–98 years) in the VA Normative Aging Study cohort. A tremor score was created based on an approach using hand-drawing samples. ALAD genotype was dichotomized as ALAD-2 carriers or not. We used linear regression adjusted for age, education, smoking, and alcohol intake to estimate the associations between lead biomarkers and tremor score. Results: In unadjusted analyses, there was a marginal association between quintiles of all lead biomarkers and tremor scores (p-values < 0.13), which did not persist in adjusted models. Age was the strongest predictor of tremor. Among those younger than the median age (68.9 years), tremor increased significantly with blood lead (p = 0.03), but this pattern was not apparent for bone lead. We did not see modification by ALAD or an association between bone lead and change in tremor score over time. Conclusion: Our results do not strongly support an association between lead exposure and tremor, and suggest no association with cumulative lead biomarkers, although there is some suggestion that blood lead may be associated with tremor among the younger men in our cohort. Citation: Ji JS, Power MC, Sparrow D, Spiro A III, Hu H, Louis ED, Weisskopf MG. 2015. Lead exposure and tremor among older men: the VA Normative Aging Study. Environ Health Perspect 123:445–450; http://dx.doi.org/10.1289/ehp.1408535

  18. 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

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

    PubMed

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

    2015-01-01

    Older adults are underrepresented in medical research for many reasons, including recruitment difficulties. Recruitment of older adults for research studies is often a time-consuming process and can be more challenging when the study involves older adults with unique exposures to traumatic events and from minority groups. The current article provides a brief overview of (a) challenges encountered while recruiting aging women Holocaust survivors for a case control study and (b) strategies used for meeting those challenges. The case group comprised women Holocaust survivors who were recently diagnosed with breast cancer and the control group comprised healthy women from a Holocaust-survivor community in Israel. PMID:26020580

  20. 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…

  1. Plasma vitamin D levels and cognitive function in aging women: the Nurses’ Health Study

    PubMed Central

    Bartali, Benedetta; Devore, Elizabeth; Grodstein, Francine; Kang, Jae H.

    2014-01-01

    Background Vitamin D may play a role in preserving cognitive function. However, there is a paucity of prospective studies on the relationship between vitamin D and cognition with aging. The aim of this study was to examine the association between plasma levels of vitamin D and subsequent cognitive function. Methods This is a prospective study including 1,185 women aged 60–70 years from the Nurses’ Health Study, who had plasma 25-hydroxy-vitamin D levels measured in 1989–1990 and completed an initial Telephone Interview of Cognitive Status approximately 9 years later. Subsequently, three follow-up cognitive assessments were conducted at 1.5–2.0 years intervals. We used multivariable-adjusted linear regression to model initial cognitive function, and mixed linear regression to model change in cognitive function over time. Results Lower vitamin D levels were associated with significantly worse cognitive function 9 years later. For example, the mean global composite score averaging all the cognitive tests was 0.20 lower (95% Confidence Interval (CI):−0.33,−0.08; p-trend=0.009) in women in the lowest quintile (median=14.1 ng/mL) compared with women in the highest quintile of vitamin D (median=38.4 ng/mL). The observed differences were equivalent to the effect estimates we found for women who were approximately 4–6 years apart in age. However, vitamin D levels were not significantly associated with subsequent cognitive decline during 6 years of follow-up. Conclusions Higher levels of plasma vitamin D in women aged 60–70 years were associated with better cognitive function about a decade later but were not associated with cognitive decline during 6 years of follow-up. PMID:24676321

  2. Structural properties of GaNAs nanowires probed by micro-Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Filippov, S.; Ishikawa, F.; Chen, W. M.; Buyanova, I. A.

    2016-02-01

    GaNAs-based nanowires (NWs) form a novel material system of potential importance for applications in advanced optoelectronic and photonic devices, thanks to the advantages provided by band-structure engineering, one-dimensional architecture and the possibility to combine them with mainstream silicon technology. In this work we utilize the micro-Raman scattering technique to systematically study the structural properties of such GaAs/GaNAs core/shell NW structures grown by molecular beam epitaxy on a Si substrate. It is shown that the employed one-dimensional architecture allows the fabrication of a GaNAs shell with a low degree of alloy disorder and weak residual strain, at least within the studied range of nitrogen (N) compositions [N] < 0.6%. Raman scattering by the GaAs-like and GaN-like phonons is found to be enhanced when the excitation energy approaches the E+ transition energy. Since this effect is found to be more pronounced for the GaN-like phonons, the involved intermediate states are concluded to be localized in proximity to N impurities, i.e. they likely represent N-related cluster states located in proximity to E+.

  3. Recombination and maternal age-dependent nondisjunction: molecular studies of trisomy 16.

    PubMed Central

    Hassold, T; Merrill, M; Adkins, K; Freeman, S; Sherman, S

    1995-01-01

    Trisomy 16 is the most common human trisomy, occurring in > or = 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 trisomy 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. PMID:7573048

  4. 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

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

    PubMed

    Belsky, Daniel W

    2016-06-15

    As the population ages, the burden of disease from cognitive decline and dementing illness is rising. In the absence of treatments to reverse cognitive decline, prevention is a public health priority. Physical fitness and physical activity have emerged as prevention targets based on evidence of "neuroprotective" benefits in observational studies. However, observational studies linking active lifestyle with successful cognitive aging might be subject to bias from "neuroselection," in which adults with better cognitive functioning are more likely to engage in healthy behaviors and avoid unhealthy ones. In their analysis of longitudinal data on several thousand children from the United Kingdom's Millennium Cohort Study, Aggio et al. (Am J Epidemiol. 2016;183(12):1075-1082) revealed that this pattern of neuroselection is already apparent in childhood. However, they also report data that suggest there are cognitive benefits to engaging in certain types of active behaviors over and above this selection. Their findings argue for greater attention to confounding by neuroselection in research on cognitive aging, and they suggest the possibility that early interventions to promote certain health behaviors may instill a virtuous cycle with benefits that accumulate across the lifespan. PMID:27226250

  6. Ageing studies of wavelength shifter fibers for the TILECAL/ATLAS experiment

    NASA Astrophysics Data System (ADS)

    Silva, J.; Maio, A.; Pina, J.; Santos, J.; Saraiva, J. G.

    2007-09-01

    Natural and accelerated ageing studies for the different components of the TILECAL calorimeter, of the ATLAS experiment, play a central role in forecasting the evolution of the detector's performance throughout its operating life. It is possible that the operation of ATLAS will be extended by 5 years in an upgraded LHC scenario. Such prospect makes these studies even more important, in order to assess the contribution of the natural ageing in relation to the other processes inducing performance loss in the optical components. Among other activities in this LHC/CERN collaboration, the Lisbon calorimetry group is involved in studying the impact of radiation damage and natural ageing in optical characteristics of the TILECAL wavelength shifter (WLS) optical fibers and scintillators, and to reevaluate the light budget of the tile/fiber system. The light yield and the attenuation length of the WLS and scintillating optical fibers are measured using an X- Y table. Results are presented for several sets of WLS optical fibers (Kuraray Y11(200)MSJ) whose characteristics have been monitored since 1999. Most of those 338 fibers are from the mass production for the TILECAL detector: 208 non-aluminized 200 cm fibers, from several production batches, and 128 batch #6 aluminized fibers, with lengths ranging from 114 to 207 cm.

  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. 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

  9. A multiple imputation approach to disclosure limitation for high-age individuals in longitudinal studies.

    PubMed

    An, Di; Little, Roderick J A; McNally, James W

    2010-07-30

    Disclosure limitation is an important consideration in the release of public use data sets. It is particularly challenging for longitudinal data sets, since information about an individual accumulates with repeated measures over time. Research on disclosure limitation methods for longitudinal data has been very limited. We consider here problems created by high ages in cohort studies. Because of the risk of disclosure, ages of very old respondents can often not be released; in particular, this is a specific stipulation of the Health Insurance Portability and Accountability Act (HIPAA) for the release of health data for individuals. Top-coding of individuals beyond a certain age is a standard way of dealing with this issue, and it may be adequate for cross-sectional data, when a modest number of cases are affected. However, this approach leads to serious loss of information in longitudinal studies when individuals have been followed for many years. We propose and evaluate an alternative to top-coding for this situation based on multiple imputation (MI). This MI method is applied to a survival analysis of simulated data, and data from the Charleston Heart Study (CHS), and is shown to work well in preserving the relationship between hazard and covariates. PMID:20552576

  10. Making heads or tails of mitochondrial membranes in longevity and aging: a role for comparative studies

    PubMed Central

    2014-01-01

    Mitochondria play vital roles in metabolic energy transduction, intermediate molecule metabolism, metal ion homeostasis, programmed cell death and regulation of the production of reactive oxygen species. As a result of their broad range of functions, mitochondria have been strongly implicated in aging and longevity. Numerous studies show that aging and decreased lifespan are also associated with high reactive oxygen species production by mitochondria, increased mitochondrial DNA and protein damage, and with changes in the fatty acid composition of mitochondrial membranes. It is possible that the extent of fatty acid unsaturation of the mitochondrial membrane determines susceptibility to lipid oxidative damage and downstream protein and genome toxicity, thereby acting as a determinant of aging and lifespan. Reviewing the vast number of comparative studies on mitochondrial membrane composition, metabolism and lifespan reveals some evidence that lipid unsaturation ratios may correlate with lifespan. However, we caution against simply relating these two traits. They may be correlative but have no functional relation. We discuss an important methodology for body mass and phylogenetic correction in comparative studies. PMID:24588808

  11. 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.

  12. 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

  13. Hippocampal tau pathology is related to neuroanatomical connections: an ageing population-based study.

    PubMed

    Lace, G; Savva, G M; Forster, G; de Silva, R; Brayne, C; Matthews, F E; Barclay, J J; Dakin, L; Ince, P G; Wharton, S B

    2009-05-01

    Deposits of abnormally phosphorylated tau protein are found in numerous neurodegenerative disorders; the 'tauopathies', which include Alzheimer's and Pick's diseases, but tau pathology is also found in the ageing brain. Variation in tau pathology in brain ageing and its relationship to development of tauopathies and cognitive impairment remains unclear. We aimed to determine the extent and pattern of spread of tau pathology in the hippocampus, a susceptible region important in dementia and milder states of memory impairment, using hippocampal samples from the elderly population-based Medical Research Council Cognitive Function and Ageing Study neuropathology cohort. Tau deposition was assessed in hippocampal anatomical sub-regions using the AT8 antibody to phosphorylated tau and isoform-specific antibodies to 3 and 4-repeat tau (RD3 and RD4). Abeta pathology was also assessed. In this population sample, which includes the full ageing spectrum from individuals with no cognitive impairment to those with dementia satisfying clinico-pathology criteria for Alzheimer's disease, we have demonstrated a high prevalence at death of tau pathology. AT8, Abeta, RD3 and RD4 showed similar regional distribution and increased RD3 was noted in late-stage ghost tangles. Abeta was shown to be a poor explanatory variable for tau pathology. Tau deposition progressed in a hierarchical manner. Hippocampal input regions and projection zones (such as lateral entorhinal cortex, CA1/subiculum border and outer molecular layer of dentate) were initially affected, with anterograde progression though the hippocampal circuitry. Six hippocampal tau anatomical stages were defined, each linking projectionally to their adjacent stages, suggesting spread of tau malfunction through neuroanatomical pathways in hippocampal ageing. These stages were significantly associated with dementia, and may provide a clinically useful tool in the clinico-pathological assessment of dementia and mild cognitive

  14. 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

  15. [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

  16. 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

  17. 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

  18. [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. PMID:26717740

  19. 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. PMID:25313793

  20. Sex, Age, Race and Intervention Type in Clinical Studies of HIV Cure: A Systematic Review

    PubMed Central

    Heitzeg, Mary M.

    2015-01-01

    Abstract 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. PMID:25313793