WorldWideScience

Sample records for bimodal age distribution

  1. A bimodal flexible distribution for lifetime data

    OpenAIRE

    Ramires, Thiago G.; Ortega, Edwin M. M.; Cordeiro, Gauss M.; Hens, Niel

    2016-01-01

    A four-parameter extended bimodal lifetime model called the exponentiated log-sinh Cauchy distribution is proposed. It extends the log-sinh Cauchy and folded Cauchy distributions. We derive some of its mathematical properties including explicit expressions for the ordinary moments and generating and quantile functions. The method of maximum likelihood is used to estimate the model parameters. We implement the fit of the model in the GAMLSS package and provide the codes. The flexibility of the...

  2. Doubly localized surface plasmon resonance in bimodally distributed silver nanoparticles.

    Science.gov (United States)

    Ranjan, M

    2012-06-01

    Growth of bimodally distributed silver nanoparticles using sequential physical vapour deposition (PVD) is reported. Growth conditions of nanoparticles are defined in the following three steps: In the first step, nanoparticles are grown at a heated substrate and then exposed to atmosphere, in the second step, nanoparticles are vacuum annealed and finally re-deposition of silver is performed in the third step. This special way of deposition leads to the formation of bimodally distributed nanoparticles. It has been investigated that by changing the deposition time, different sets of bimodally distributed nanoparticles can be grown. Localized surface plasmon resonance (LSPR) of such bimodally distributed nanoparticles generates double plasmon resonance peaks with overlapped absorption spectra. Double plasmon resonance peaks provide a quick indication of the existence of two sets of nanoparticles. LSPR spectra of such bimodally distributed nanoparticles could be modeled with double Lorentz oscillator model. Inclusion of double Lorentz oscillator model indicates that there exist two sets of non-interacting nanoparticles resonating at different plasma frequencies. It is also reported that silver nanoparticles grown at a heated substrate, again attain the new shape while being exposed to atmosphere, followed by vacuum annealing at the same temperature. This is because of physisorption of oxygen at the silver surface and change in surface free energy. The re-shaping due to the adsorbed oxygen on the surface is responsible for bimodal size distribution of nanoparticles.

  3. Asymmetric Bimodal Exponential Power Distribution on the Real Line

    Directory of Open Access Journals (Sweden)

    Mehmet Niyazi Çankaya

    2018-01-01

    Full Text Available The asymmetric bimodal exponential power (ABEP distribution is an extension of the generalized gamma distribution to the real line via adding two parameters that fit the shape of peakedness in bimodality on the real line. The special values of peakedness parameters of the distribution are a combination of half Laplace and half normal distributions on the real line. The distribution has two parameters fitting the height of bimodality, so capacity of bimodality is enhanced by using these parameters. Adding a skewness parameter is considered to model asymmetry in data. The location-scale form of this distribution is proposed. The Fisher information matrix of these parameters in ABEP is obtained explicitly. Properties of ABEP are examined. Real data examples are given to illustrate the modelling capacity of ABEP. The replicated artificial data from maximum likelihood estimates of parameters of ABEP and other distributions having an algorithm for artificial data generation procedure are provided to test the similarity with real data. A brief simulation study is presented.

  4. The Bimodal Color Distribution of Small Kuiper Belt Objects

    Science.gov (United States)

    Wong, Ian; Brown, Michael E.

    2017-04-01

    We conducted a two-night photometric survey of small Kuiper Belt objects (KBOs) near opposition using the wide-field Hyper Suprime-Cam instrument on the 8.2 m Subaru Telescope. The survey covered about 90 deg2 of sky, with each field imaged in the g and I bands. We detected 356 KBOs, ranging in absolute magnitude from 6.5 to 10.4. Filtering for high-inclination objects within the hot KBO population, we show that the g - I color distribution is strongly bimodal, indicative of two color classes—the red and very red subpopulations. After categorizing objects into the two subpopulations by color, we present the first dedicated analysis of the magnitude distributions of the individual color subpopulations and demonstrate that the two distributions are roughly identical in shape throughout the entire size range covered by our survey. Comparing the color distribution of small hot KBOs with that of Centaurs, we find that they have similar bimodal shapes, thereby providing strong confirmation of previous explanations for the attested bimodality of Centaurs. We also show that the magnitude distributions of the two KBO color subpopulations and the two color subpopulations observed in the Jupiter Trojans are statistically indistinguishable. Finally, we discuss a hypothesis describing the origin of the KBO color bimodality based on our survey results. Based on data collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.

  5. Resolving the age bimodality of galaxy stellar populations on kpc scales

    NARCIS (Netherlands)

    Zibetti, Stefano; Gallazzi, Anna R.; Ascasibar, Y.; Charlot, S.; Galbany, L.; García Benito, R.; Kehrig, C.; de Lorenzo-Cáceres, A.; Lyubenova, M.; Marino, R. A.; Márquez, I.; Sánchez, S. F.; van de Ven, G.; Walcher, C. J.; Wisotzki, L.

    2017-01-01

    Galaxies in the local Universe are known to follow bimodal distributions in the global stellar population properties. We analyse the distribution of the local average stellar population ages of 654 053 sub-galactic regions resolved on ˜1 kpc scales in a volume-corrected sample of 394 galaxies, drawn

  6. Resolving the age bimodality of galaxy stellar populations on kpc scales

    Science.gov (United States)

    Zibetti, Stefano; Gallazzi, Anna R.; Ascasibar, Y.; Charlot, S.; Galbany, L.; García Benito, R.; Kehrig, C.; de Lorenzo-Cáceres, A.; Lyubenova, M.; Marino, R. A.; Márquez, I.; Sánchez, S. F.; van de Ven, G.; Walcher, C. J.; Wisotzki, L.

    2017-06-01

    Galaxies in the local Universe are known to follow bimodal distributions in the global stellar population properties. We analyse the distribution of the local average stellar population ages of 654 053 sub-galactic regions resolved on ˜1 kpc scales in a volume-corrected sample of 394 galaxies, drawn from the Calar Alto Legacy Integral Field Area (CALIFA) DR3 integral-field-spectroscopy survey and complemented by Sloan Digital Sky Survey (SDSS) imaging. We find a bimodal local-age distribution, with an old and a young peak primarily due to regions in early-type galaxies and star-forming regions of spirals, respectively. Within spiral galaxies, the older ages of bulges and interarm regions relative to spiral arms support an internal age bimodality. Although regions of higher stellar mass surface density, μ*, are typically older, μ* alone does not determine the stellar population age and a bimodal distribution is found at any fixed μ*. We identify an 'old ridge' of regions of age ˜9 Gyr, independent of μ*, and a 'young sequence' of regions with age increasing with μ* from 1-1.5 to 4-5 Gyr. We interpret the former as regions containing only old stars, and the latter as regions where the relative contamination of old stellar populations by young stars decreases as μ* increases. The reason why this bimodal age distribution is not inconsistent with the unimodal shape of the cosmic-averaged star formation history is that (I) the dominating contribution by young stars biases the age low with respect to the average epoch of star formation, and (II) the use of a single average age per region is unable to represent the full time extent of the star formation history of 'young sequence' regions.

  7. Rapid intensification and the bimodal distribution of tropical cyclone intensity.

    Science.gov (United States)

    Lee, Chia-Ying; Tippett, Michael K; Sobel, Adam H; Camargo, Suzana J

    2016-02-03

    The severity of a tropical cyclone (TC) is often summarized by its lifetime maximum intensity (LMI), and the climatological LMI distribution is a fundamental feature of the climate system. The distinctive bimodality of the LMI distribution means that major storms (LMI >96 kt) are not very rare compared with less intense storms. Rapid intensification (RI) is the dramatic strengthening of a TC in a short time, and is notoriously difficult to forecast or simulate. Here we show that the bimodality of the LMI distribution reflects two types of storms: those that undergo RI during their lifetime (RI storms) and those that do not (non-RI storms). The vast majority (79%) of major storms are RI storms. Few non-RI storms (6%) become major storms. While the importance of RI has been recognized in weather forecasting, our results demonstrate that RI also plays a crucial role in the TC climatology.

  8. Multifractal Characteristics of Bimodal Mercury Pore Size Distribution Curves

    Science.gov (United States)

    dos Santos Bonini, C.; Alves, M. C.; Paz González, A.

    2012-04-01

    Characterization of Hg pore size distribution (PSDs) curves by monofractal or multifractal analysis has been demonstrated to be an useful tool, which allows a better understanding of the organization of the soil pore space. There are also evidences that multiscale analysis of different segments found in bimodal pore size distributions measured by Hg intrusion can provide further valuable information. In this study we selected bimodal PSDs from samples taken from an experimental area in São Paulo state, Brazil, where a revegetation trial was set up over saprolitic material. The saprolite was left abandoned after decapitation of an Oxisol for building purposes. The field trial consisted of various treatments with different grass species and amendments. Pore size distribution of the sampled aggregates was measured in the equivalent diameter range from 0.005 to about 50 μm and it was characterized by a bimodal pattern, so that two compartments, i.e. 0.005 to 0.2 μm and 0.2 to 50 μm, could be distinguished. The multifractal theory was used to analyse both segments. The scaling properties of these two segments could be fitted reasonably well with multifractal models. Multifractal parameters obtained for equivalent diameters for the segments > 0.2 and pore size distributions studied.

  9. mocca code for star cluster simulations - VI. Bimodal spatial distribution of blue stragglers

    Science.gov (United States)

    Hypki, Arkadiusz; Giersz, Mirek

    2017-11-01

    The paper presents an analysis of formation mechanism and properties of spatial distributions of blue stragglers in evolving globular clusters, based on numerical simulations done with the mocca code. First, there are presented N-body and mocca simulations which try to reproduce the simulations presented by Ferraro et al. (2012). Then, we show the agreement between N-body and the mocca code. Finally, we discuss the formation process of the bimodal distribution. We report that we could not reproduce simulations from Ferraro et al. (2012). Moreover, we show that the so-called bimodal spatial distribution of blue stragglers is a very transient feature. It is formed for one snapshot in time and it can easily vanish in the next one. Moreover, we show that the radius of avoidance proposed by Ferraro et al. (2012) goes out of sync with the apparent minimum of the bimodal distribution after about two half-mass relaxation times (without finding out what is the reason for that). This finding creates a real challenge for the dynamical clock, which uses this radius to determine the dynamical age of globular clusters. Additionally, the paper discusses a few important problems concerning the apparent visibilities of the bimodal distributions, which have to be taken into account while studying the spatial distributions of blue stragglers.

  10. Age bimodality in the central region of pseudo-bulges in S0 galaxies

    Science.gov (United States)

    Mishra, Preetish K.; Barway, Sudhanshu; Wadadekar, Yogesh

    2017-11-01

    We present evidence for bimodal stellar age distribution of pseudo-bulges of S0 galaxies as probed by the Dn(4000) index. We do not observe any bimodality in age distribution for pseudo-bulges in spiral galaxies. Our sample is flux limited and contains 2067 S0 and 2630 spiral galaxies drawn from the Sloan Digital Sky Survey. We identify pseudo-bulges in S0 and spiral galaxies, based on the position of the bulge on the Kormendy diagram and their central velocity dispersion. Dividing the pseudo-bulges of S0 galaxies into those containing old and young stellar populations, we study the connection between global star formation and pseudo-bulge age on the u - r colour-mass diagram. We find that most old pseudo-bulges are hosted by passive galaxies while majority of young bulges are hosted by galaxies that are star forming. Dividing our sample of S0 galaxies into early-type S0s and S0/a galaxies, we find that old pseudo-bulges are mainly hosted by early-type S0 galaxies while most of the pseudo-bulges in S0/a galaxies are young. We speculate that morphology plays a strong role in quenching of star formation in the disc of these S0 galaxies, which stops the growth of pseudo-bulges, giving rise to old pseudo-bulges and the observed age bimodality.

  11. Bimodal distribution of damage morphology generated by ion implantation

    International Nuclear Information System (INIS)

    Mok, K.R.C.; Jaraiz, M.; Martin-Bragado, I.; Rubio, J.E.; Castrillo, P.; Pinacho, R.; Srinivasan, M.P.; Benistant, F.

    2005-01-01

    A nucleation and evolution model of damage based on amorphous pockets (APs) has recently been developed and implemented in an atomistic kinetic Monte Carlo simulator. In the model, APs are disordered structures (I n V m ), which are agglomerates of interstitials (I) and vacancies (V). This model has been used to study the composition and size distribution of APs during different ion implantations. Depending strongly on the dose rate, ion mass and implant temperature, the APs can evolve to a defect population where the agglomerates have a similar number of I and V (n ∼ m), or to a defect population with pure I (m ∼ 0) and pure V (n ∼ 0) clusters, or a mixture of APs and clusters. This behaviour corresponds to a bimodal (APs/clusters) distribution of damage. As the AP have different thermal stability compared to the I and V clusters, the same damage concentration obtained through different implant conditions has a different damage morphology and, consequently, exhibit a different resistance to subsequent thermal treatments

  12. The climatic imprint of bimodal distributions in vegetation cover for western Africa

    NARCIS (Netherlands)

    Yin, Z.; Dekker, S. C.; van den Hurk, B. J. J. M.; Dijkstra, H. A.

    2016-01-01

    Observed bimodal distributions of woody cover in western Africa provide evidence that alternative ecosystem states may exist under the same precipitation regimes. In this study, we show that bimodality can also be observed in mean annual shortwave radiation and above-ground biomass, which might

  13. Bimodal distribution of glucose is not universally useful for diagnosing diabetes

    DEFF Research Database (Denmark)

    Vistisen, Dorte; Colagiuri, Stephen; Borch-Johnsen, Knut

    2009-01-01

    OBJECTIVE: Bimodality in the distribution of glucose has been used to define the cut point for the diagnosis of diabetes. Previous studies on bimodality have primarily been in populations with a high prevalence of type 2 diabetes, including one study in a white Caucasian population. All studies i...

  14. Yield stress of ultrafine-grained or nanocrystalline materials with a bimodal grain size distribution

    Science.gov (United States)

    Pande, C. S.; DeGiorgi, V. G.; E Moser, A.

    2018-02-01

    An attractive processing route for enhancing the yield strength of high-strength nanocrystalline metals and alloys while maintaining high ductility is to develop a bimodal grain size distribution (GSD), in which, supposedly, the finer grains provide strength, and the coarser grains maintain or even enhance ductility. We present a theoretical model predicting the strength of such a system, and show, analytically, how the yield stress is related to the various parameters of the bimodal GSD, such as volume fraction of the two components of the bimodal distribution and their standard deviations.

  15. Quantum treatment of laser cooling on weak transitions: multipeaks and bimodal momentum distributions

    Science.gov (United States)

    Ilenkov, R. Ya; Taichenachev, A. V.; Yudin, V. I.; Prudnikov, O. N.

    2018-01-01

    The work is devoted to the study of the features and parameters of the momentum distributions of atoms laser cooled on weak optical transitions. It was shown that atoms distributions are described by a bimodal momentum distribution whose characteristics depends on the parameters of the light field. In a strong field a velocity selective coherent population trapping effect is observed.

  16. Bimodal grain-size distribution of Chinese loess, and its palaeoclimatic implications

    NARCIS (Netherlands)

    Sun, D.G.; Bloemendal, J.; Rea, D.K.; An, Z.S.; Vandenberghe, J.; Lu, H.; Su, R.; Liu, T.S.

    2004-01-01

    Grain-size analysis indicates that Chinese loess generally shows a bimodal distribution with a coarse and a fine component. The coarse component, comprising the main part of the loess, has pronounced kurtosis and is well sorted, which is interpreted to be the product of dust storms generated by

  17. Looking for bimodal distributions in multi-fragmentation reactions

    International Nuclear Information System (INIS)

    Gulminelli, F.

    2007-01-01

    The presence of a phase transition in a finite system can be deduced, together with its order, from the form of the distribution of the order parameter. This issue has been extensively studied in multifragmentation experiments, with results that do not appear fully consistent. In this paper we discuss the effect of the statistical ensemble or sorting conditions on the form of fragment distributions, and propose a new method, which can be easily implemented experimentally, to discriminate between different fragmentation scenarios. This method, based on a re-weighting of the measured distribution to account for the experimental constraints linked to the energy deposit, is tested on different simple models, and appears to provide a powerful discrimination. (author)

  18. Bimodal score distributions and the Myers-Briggs Type Indicator: fact or artifact?

    Science.gov (United States)

    Bess, Tammy L; Harvey, Robert J

    2002-02-01

    We examined Myers-Briggs Type Indicator (MBTI) score distributions computed using item response theory (IRT) to assess the generalizability of earlier bimodality reports that have been cited in support of the "type" versus "trait" view of personality. Using the BILOG IRT program to score a sample of approximately 12,000 individuals who participated in leadership development programs, theta score distributions for the 4 dimensions of the MBTI computed using 10 (the BILOG default) versus 50 quadrature points were compared. Results indicated that past reports of bimodality were artifacts caused by BILOG's default use of a small number of quadrature points; when larger numbers of points were used, score distributions became strongly center-weighted. Although our findings are not supportive of the "type"-based hypothesis, the extremely high correlations between theta scores (rs > .996) suggest that no practical differences would be expected as a function of the number-of-quadrature-points decision.

  19. Exact results for the Kuramoto model with a bimodal frequency distribution

    DEFF Research Database (Denmark)

    Martens, Erik Andreas; Barreto, E.; Strogatz, S. H.

    2009-01-01

    We analyze a large system of globally coupled phase oscillators whose natural frequencies are bimodally distributed. The dynamics of this system has been the subject of long-standing interest. In 1984 Kuramoto proposed several conjectures about its behavior; ten years later, Crawford obtained...... the first analytical results by means of a local center manifold calculation. Nevertheless, many questions have remained open, especially about the possibility of global bifurcations. Here we derive the system’s stability diagram for the special case where the bimodal distribution consists of two equally......, where all the oscillators are desynchronized; partial synchrony, where a macro- scopic group of phase-locked oscillators coexists with a sea of desynchronized ones; and a standing wave state, where two counter-rotating groups of phase-locked oscillators emerge. Analytical results are presented...

  20. Annual and diurnal precipitation bimodal distributions as simulated by WRF-based CORDEX-Cetral America

    Science.gov (United States)

    Angel, M. C.; Mejia, J.; Chang, H. I.; Ochoa, C. A.; Castro, C. L.

    2017-12-01

    We examine the ability of a regional climate model (RCM) to simulate the observed annual and diurnal cycles of precipitation over Central America (CA), the Caribbean Sea and NW South America (NWSA). The region's annual cycle is dominated by a bimodal precipitation annual cycle: over CA and the Caribbean, the mid-summer drought suppresses the rainy season in July-August; over the NWSA, and more pronouncedly over the Andes, the ITCZ meridional migration is argue to dominate the bimodal distribution of the annual cycle. The intricate land-ocean distribution, the complex terrain, and the long lasting mesoscale convective systems have been related to intricate bimodal diurnal distribution of precipitation over the far eastern Pacific and NWSA. A CORDEX-CA simulation based on the Weather and Research Forecasting (WRF) model at 25 km grid size driven by ERA-Interim reanalysis for the period 1979-2015 was implemented. The simulations were evaluated using surface observations and the research-based High-Resolution Satellite Precipitation Product from TRMM (3B42) and CMORPH. We use spectral analysis to estimate the mean phase and amplitude spatial patterns at annual and diurnal time scales. We further contrast the consistencies and differences using more focus and higher resolution simulations based on WRF and ERA-Interim at 10km and convection-permitting simulations (<4 km grid sizes). The research discusses the flow and orographic dependencies on the ability to adequately simulate the annual and diurnal bimodal distributions of precipitation. These comparisons provide a high-level validation of the WRF-based CORDEX-CA's ability to simulate one of the rainniest region on earth and its basic but challenging small-scale spatial-temporal climate variations.

  1. How bilingualism protects the brain from aging: Insights from bimodal bilinguals.

    Science.gov (United States)

    Li, Le; Abutalebi, Jubin; Emmorey, Karen; Gong, Gaolang; Yan, Xin; Feng, Xiaoxia; Zou, Lijuan; Ding, Guosheng

    2017-08-01

    Bilingual experience can delay cognitive decline during aging. A general hypothesis is that the executive control system of bilinguals faces an increased load due to controlling two languages, and this increased load results in a more "tuned brain" that eventually creates a neural reserve. Here we explored whether such a neuroprotective effect is independent of language modality, i.e., not limited to bilinguals who speak two languages but also occurs for bilinguals who use a spoken and a signed language. We addressed this issue by comparing bimodal bilinguals to monolinguals in order to detect age-induced structural brain changes and to determine whether we can detect the same beneficial effects on brain structure, in terms of preservation of gray matter volume (GMV), for bimodal bilinguals as has been reported for unimodal bilinguals. Our GMV analyses revealed a significant interaction effect of age × group in the bilateral anterior temporal lobes, left hippocampus/amygdala, and left insula where bimodal bilinguals showed slight GMV increases while monolinguals showed significant age-induced GMV decreases. We further found through cortical surface-based measurements that this effect was present for surface area and not for cortical thickness. Moreover, to further explore the hypothesis that overall bilingualism provides neuroprotection, we carried out a direct comparison of GMV, extracted from the brain regions reported above, between bimodal bilinguals, unimodal bilinguals, and monolinguals. Bilinguals, regardless of language modality, exhibited higher GMV compared to monolinguals. This finding highlights the general beneficial effects provided by experience handling two language systems, whether signed or spoken. Hum Brain Mapp 38:4109-4124, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  2. The climatic imprint of bimodal distributions in vegetation cover for western Africa

    Science.gov (United States)

    Yin, Zun; Dekker, Stefan C.; van den Hurk, Bart J. J. M.; Dijkstra, Henk A.

    2016-06-01

    Observed bimodal distributions of woody cover in western Africa provide evidence that alternative ecosystem states may exist under the same precipitation regimes. In this study, we show that bimodality can also be observed in mean annual shortwave radiation and above-ground biomass, which might closely relate to woody cover due to vegetation-climate interactions. Thus we expect that use of radiation and above-ground biomass enables us to distinguish the two modes of woody cover. However, through conditional histogram analysis, we find that the bimodality of woody cover still can exist under conditions of low mean annual shortwave radiation and low above-ground biomass. It suggests that this specific condition might play a key role in critical transitions between the two modes, while under other conditions no bimodality was found. Based on a land cover map in which anthropogenic land use was removed, six climatic indicators that represent water, energy, climate seasonality and water-radiation coupling are analysed to investigate the coexistence of these indicators with specific land cover types. From this analysis we find that the mean annual precipitation is not sufficient to predict potential land cover change. Indicators of climate seasonality are strongly related to the observed land cover type. However, these indicators cannot predict a stable forest state under the observed climatic conditions, in contrast to observed forest states. A new indicator (the normalized difference of precipitation) successfully expresses the stability of the precipitation regime and can improve the prediction accuracy of forest states. Next we evaluate land cover predictions based on different combinations of climatic indicators. Regions with high potential of land cover transitions are revealed. The results suggest that the tropical forest in the Congo basin may be unstable and shows the possibility of decreasing significantly. An increase in the area covered by savanna and grass

  3. Bimodal distribution of the magnetic dipole moment in nanoparticles with a monomodal distribution of the physical size

    International Nuclear Information System (INIS)

    Rijssel, Jos van; Kuipers, Bonny W.M.; Erné, Ben H.

    2015-01-01

    High-frequency applications of magnetic nanoparticles, such as therapeutic hyperthermia and magnetic particle imaging, are sensitive to nanoparticle size and dipole moment. Usually, it is assumed that magnetic nanoparticles with a log-normal distribution of the physical size also have a log-normal distribution of the magnetic dipole moment. Here, we test this assumption for different types of superparamagnetic iron oxide nanoparticles in the 5–20 nm range, by multimodal fitting of magnetization curves using the MINORIM inversion method. The particles are studied while in dilute colloidal dispersion in a liquid, thereby preventing hysteresis and diminishing the effects of magnetic anisotropy on the interpretation of the magnetization curves. For two different types of well crystallized particles, the magnetic distribution is indeed log-normal, as expected from the physical size distribution. However, two other types of particles, with twinning defects or inhomogeneous oxide phases, are found to have a bimodal magnetic distribution. Our qualitative explanation is that relatively low fields are sufficient to begin aligning the particles in the liquid on the basis of their net dipole moment, whereas higher fields are required to align the smaller domains or less magnetic phases inside the particles. - Highlights: • Multimodal fits of dilute ferrofluids reveal when the particles are multidomain. • No a priori shape of the distribution is assumed by the MINORIM inversion method. • Well crystallized particles have log-normal TEM and magnetic size distributions. • Defective particles can combine a monomodal size and a bimodal dipole moment

  4. X-ray diffraction microstructural analysis of bimodal size distribution MgO nano powder

    International Nuclear Information System (INIS)

    Suminar Pratapa; Budi Hartono

    2009-01-01

    Investigation on the characteristics of x-ray diffraction data for MgO powdered mixture of nano and sub-nano particles has been carried out to reveal the crystallite-size-related microstructural information. The MgO powders were prepared by co-precipitation method followed by heat treatment at 500 degree Celsius and 1200 degree Celsius for 1 hour, being the difference in the temperature was to obtain two powders with distinct crystallite size and size-distribution. The powders were then blended in air to give the presumably bimodal-size- distribution MgO nano powder. High-quality laboratory X-ray diffraction data for the powders were collected and then analysed using Rietveld-based MAUD software using the lognormal size distribution. Results show that the single-mode powders exhibit spherical crystallite size (R) of 20(1) nm and 160(1) nm for the 500 degree Celsius and 1200 degree Celsius data respectively with the nano metric powder displays narrower crystallite size distribution character, indicated by lognormal dispersion parameter of 0.21 as compared to 0.01 for the sub-nano metric powder. The mixture exhibits relatively more asymmetric peak broadening. Analysing the x-ray diffraction data for the latter specimen using single phase approach give unrealistic results. Introducing two phase models for the double-phase mixture to accommodate the bimodal-size-distribution characteristics give R = 100(6) and σ = 0.62 for the nano metric phase and R = 170(5) and σ= 0.12 for the σ sub-nano metric phase. (author)

  5. Investigation on the Bimodal Distribution of the Duration of Gamma-ray Bursts from BATSE Light Curves

    OpenAIRE

    Yu, Wenfei; Li, Tipei; Wu, Mei

    1999-01-01

    We have investigated the bimodal distribution of the duration of BATSE gamma-ray bursts (GRBs) by analyzing light curves of 64 ms time resolution. We define the average pulse width of GRBs from the auto-correlation function of GRB profiles. The distribution of the average pulse width of GRBs is bimodal, suggesting that GRBs are composed of long-pulse GRBs and short-pulse GRBs. The average pulse width of long-pulse GRBs appears correlated with the peak flux, consistent with the time dilation e...

  6. Superferromagnetism in mechanically alloyed fcc Fe23Cu77 with bimodal cluster size distribution

    International Nuclear Information System (INIS)

    Silva, N J O; Amaral, J S; Amaral, V S; Costa, B F O; Le Caer, G

    2009-01-01

    Magnetic measurements, x-ray diffraction and Moessbauer spectroscopy were used to characterize a nanostructured fcc Fe 23 Cu 77 at.% alloy prepared by high-energy ball-milling, addressing in particular the effect of clustering on the nature of the interacting magnetic entities. The interpretation of magnetization measurements leads to the conclusion that grains, whose mean size is ∼16 nm, contain two populations of magnetic Fe-rich nanoclusters with a bimodal size distribution. These two sets of clusters contain about 14 and 400 Fe atoms and have magnetic moments of 30 μ B and 860 μ B , respectively. The inter-cluster ferromagnetic interactions that lead to superferromagnetism with a Curie temperature T C ∼220 K can be described by a mean field determined by the smaller clusters only, which account for 90% of the magnetization.

  7. Bimodal distribution of risk for childhood obesity in urban Baja California, Mexico.

    Science.gov (United States)

    Wojcicki, Janet M; Jimenez-Cruz, Arturo; Bacardi-Gascon, Montserrat; Schwartz, Norah; Heyman, Melvin B

    2012-08-01

    In Mexico, higher socioeconomic status (SES) has been found to be associated with increased risk for obesity in children. Within developed urban areas, however, there may be increased risk among lower SES children. Students in grades 4-6 from five public schools in Tijuana and Tecate, Mexico, were interviewed and weight, height and waist circumference (WC) measurements were taken. Interviews consisted of questions on food frequency, food insecurity, acculturation, physical activity and lifestyle practices. Multivariate logistic models were used to assess risk factors for obesity (having a body mass index [BMI] ≥95th percentile) and abdominal obesity (a WC >90th percentile) using Stata 11.0. Five hundred and ninety students were enrolled; 43.7% were overweight or obese, and 24.3% were obese and 20.2% had abdominal obesity. Independent risk factors for obesity included watching TV in English (odds ratio [OR] 1.60, 95% confidence interval [CI] 1.06-2.41) and perceived child food insecurity (OR 1.57, 95% CI 1.05-2.36). Decreased risk for obesity was associated with female sex (OR 0.64, 95% CI 0.43-0.96), as was regular multivitamin use (OR 0.63, 95% CI 0.42-0.94). Risk obesity was also decreased with increased taco consumption (≥1×/week; OR 0.64, 95% CI 0.43-0.96). Independent risk factors for abdominal obesity included playing video games ≥1×/week (OR 1.18, 95% CI 1.11-2.96) and older age group (10-11 years, OR 2.47, 95% CI 1.29-4.73 and ≥12 years, OR 2.21, 95% CI 1.09-4.49). Increased consumption of tacos was also associated with decreased risk for abdominal obesity (≥1×/week; OR 0.56, 95% CI 0.40-1.00). We found a bimodal distribution for risk of obesity and abdominal obesity in school aged children on the Mexican border with the United States. Increased risk for obesity and abdominal obesity were associated with factors indicative of lower and higher SES including watching TV in English, increased video game playing and perceived food insecurity

  8. Influence of age, spatial memory, and ocular fixation on localization of auditory, visual, and bimodal targets by human subjects.

    Science.gov (United States)

    Dobreva, Marina S; O'Neill, William E; Paige, Gary D

    2012-12-01

    A common complaint of the elderly is difficulty identifying and localizing auditory and visual sources, particularly in competing background noise. Spatial errors in the elderly may pose challenges and even threats to self and others during everyday activities, such as localizing sounds in a crowded room or driving in traffic. In this study, we investigated the influence of aging, spatial memory, and ocular fixation on the localization of auditory, visual, and combined auditory-visual (bimodal) targets. Head-restrained young and elderly subjects localized targets in a dark, echo-attenuated room using a manual laser pointer. Localization accuracy and precision (repeatability) were quantified for both ongoing and transient (remembered) targets at response delays up to 10 s. Because eye movements bias auditory spatial perception, localization was assessed under target fixation (eyes free, pointer guided by foveal vision) and central fixation (eyes fixed straight ahead, pointer guided by peripheral vision) conditions. Spatial localization across the frontal field in young adults demonstrated (1) horizontal overshoot and vertical undershoot for ongoing auditory targets under target fixation conditions, but near-ideal horizontal localization with central fixation; (2) accurate and precise localization of ongoing visual targets guided by foveal vision under target fixation that degraded when guided by peripheral vision during central fixation; (3) overestimation in horizontal central space (±10°) of remembered auditory, visual, and bimodal targets with increasing response delay. In comparison with young adults, elderly subjects showed (1) worse precision in most paradigms, especially when localizing with peripheral vision under central fixation; (2) greatly impaired vertical localization of auditory and bimodal targets; (3) increased horizontal overshoot in the central field for remembered visual and bimodal targets across response delays; (4) greater vulnerability to

  9. Diverse Kir expression contributes to distinct bimodal distribution of resting potentials and vasotone responses of arterioles.

    Directory of Open Access Journals (Sweden)

    Yuqin Yang

    Full Text Available The resting membrane potential (RP of vascular smooth muscle cells (VSMCs is a major determinant of cytosolic calcium concentration and vascular tone. The heterogeneity of RPs and its underlying mechanism among different vascular beds remain poorly understood. We compared the RPs and vasomotion properties between the guinea pig spiral modiolar artery (SMA, brain arterioles (BA and mesenteric arteries (MA. We found: 1 RPs showed a robust bimodal distribution peaked at -76 and -40 mV evenly in the SMA, unevenly at -77 and -51 mV in the BA and ~-71 and -52 mV in the MA. Ba(2+ 0.1 mM eliminated their high RP peaks ~-75 mV. 2 Cells with low RP (~-45 mV hyperpolarized in response to 10 mM extracellular K(+, while cells with a high RP depolarized, and cells with intermediate RP (~-58 mV displayed an initial hyperpolarization followed by prolonged depolarization. Moderate high K(+ typically induced dilation, constriction and a dilation followed by constriction in the SMA, MA and BA, respectively. 3 Boltzmann-fit analysis of the Ba(2+-sensitive inward rectifier K(+ (Kir whole-cell current showed that the maximum Kir conductance density significantly differed among the vessels, and the half-activation voltage was significantly more negative in the MA. 4 Corresponding to the whole-cell data, computational modeling simulated the three RP distribution patterns and the dynamics of RP changes obtained experimentally, including the regenerative swift shifts between the two RP levels after reaching a threshold. 5 Molecular works revealed strong Kir2.1 and Kir2.2 transcripts and Kir2.1 immunolabeling in all 3 vessels, while Kir2.3 and Kir2.4 transcript levels varied. We conclude that a dense expression of functional Kir2.X channels underlies the more negative RPs in endothelial cells and a subset of VSMC in these arterioles, and the heterogeneous Kir function is primarily responsible for the distinct bimodal RPs among these arterioles. The fast Kir

  10. Diverse Kir Expression Contributes to Distinct Bimodal Distribution of Resting Potentials and Vasotone Responses of Arterioles

    Science.gov (United States)

    Yang, Yuqin; Chen, Fangyi; Karasawa, Takatoshi; Ma, Ke-Tao; Guan, Bing-Cai; Shi, Xiao-Rui; Li, Hongzhe; Steyger, Peter S.; Nuttall, Alfred L.; Jiang, Zhi-Gen

    2015-01-01

    The resting membrane potential (RP) of vascular smooth muscle cells (VSMCs) is a major determinant of cytosolic calcium concentration and vascular tone. The heterogeneity of RPs and its underlying mechanism among different vascular beds remain poorly understood. We compared the RPs and vasomotion properties between the guinea pig spiral modiolar artery (SMA), brain arterioles (BA) and mesenteric arteries (MA). We found: 1) RPs showed a robust bimodal distribution peaked at -76 and -40 mV evenly in the SMA, unevenly at -77 and -51 mV in the BA and ~-71 and -52 mV in the MA. Ba2+ 0.1 mM eliminated their high RP peaks ~-75 mV. 2) Cells with low RP (~-45 mV) hyperpolarized in response to 10 mM extracellular K+, while cells with a high RP depolarized, and cells with intermediate RP (~-58 mV) displayed an initial hyperpolarization followed by prolonged depolarization. Moderate high K+ typically induced dilation, constriction and a dilation followed by constriction in the SMA, MA and BA, respectively. 3) Boltzmann-fit analysis of the Ba2+-sensitive inward rectifier K+ (Kir) whole-cell current showed that the maximum Kir conductance density significantly differed among the vessels, and the half-activation voltage was significantly more negative in the MA. 4) Corresponding to the whole-cell data, computational modeling simulated the three RP distribution patterns and the dynamics of RP changes obtained experimentally, including the regenerative swift shifts between the two RP levels after reaching a threshold. 5) Molecular works revealed strong Kir2.1 and Kir2.2 transcripts and Kir2.1 immunolabeling in all 3 vessels, while Kir2.3 and Kir2.4 transcript levels varied. We conclude that a dense expression of functional Kir2.X channels underlies the more negative RPs in endothelial cells and a subset of VSMC in these arterioles, and the heterogeneous Kir function is primarily responsible for the distinct bimodal RPs among these arterioles. The fast Kir-based regenerative shifts

  11. Evidence of A Bimodal US GDP Growth Rate Distribution: A Wavelet Approach

    Directory of Open Access Journals (Sweden)

    Sandro Claudio Lera

    2017-04-01

    Full Text Available We present a quantitative characterisation of the fluctuations of the annualized growth rate of the real US GDP per capita at many scales, using a wavelet transform analysis of two data sets, quarterly data from 1947 to 2015 and annual data from 1800 to 2010. The chosen mother wavelet (first derivative of the Gaussian function applied to the logarithm of the real US GDP per capita provides a robust estimation of the instantaneous growth rate at different scales. Our main finding is that business cycles appear at all scales and the distribution of GDP growth rates can be well approximated by a bimodal function associated to a series of switches between regimes of strong growth rate $\\rho_\\text{high}$ and regimes of low growth rate $\\rho_\\text{low}$. The succession of such two regimes compounds to produce a remarkably stable long term average real annualized growth rate of 1.6% from 1800 to 2010 and $\\approx 2.0\\%$ since 1950, which is the result of a subtle compensation between the high and low growth regimes that alternate continuously. Thus, the overall growth dynamics of the US economy is punctuated, with phases of strong growth that are intrinsically unsustainable, followed by corrections or consolidation until the next boom starts. We interpret these findings within the theory of "social bubbles" and argue as a consequence that estimations of the cost of the 2008 crisis may be misleading. We also interpret the absence of strong recovery since 2008 as a protracted low growth regime $\\rho_\\text{low}$ associated with the exceptional nature of the preceding large growth regime.

  12. Bulk rock and melt inclusion analyses indicate bimodal distribution in Calbuco volcano (Chile)

    Science.gov (United States)

    Montalbano, Salvatrice; Bolle, Olivier; Schiano, Pierre; Cluzel, Nicolas; Vander Auwera, Jacqueline

    2014-05-01

    Calbuco is an active stratovolcano situated in the central SVZ (Southern Volcanic Zone) of the Andes at 41.2°S. The dominant rock-type is basaltic andesite containing macrocrysts of plagioclase (An57-91), olivine (Fo60-81), clinopyroxene (Mg# 74-85), orthopyroxene (Mg# 66-75) and rare amphibole (mostly pargasitic) in a micro-crystalline matrix. Orthopyroxene frequently occurs as a reaction rim surrounding olivine suggestive of a peritectic reaction. The oldest lava unit (Calbuco 1) contains basaltic andesites that are notably lower in MgO and higher in Al2O3 than the other samples. Some dacitic compositions have also been identified. Bulk rock analyses define a low-K calc-alkaline trend with however two basalts plotting in the tholeiite field in the AFM diagram. Bulk rocks display a differentiation trend of decreasing CaO, FeOt and MgO and increasing K2O and P2O5 with increasing SiO2. Typical negative anomalies in Nb, Ta and Th are shown in spiderdiagrams whereas there is no Eu anomaly in REE patterns. In variation diagrams, a clear compositional gap occurs between 61 and 65 wt. % SiO2. Investigation of melt inclusions was performed on homogenized and naturally quenched inclusions hosted in olivine and clinopyroxene crystals. Their composition mimics the differentiation trend observed in the bulk samples, including a bimodal distribution. The melt inclusions analyzed in olivine range in composition from 45 to 58 wt. % SiO2 whereas those occurring in clinopyroxene range from 70 and 76 wt. % SiO2. The compositional gap of the melt inclusions thus overlaps that of the whole rocks. The observed differentiation trend from basalt to basaltic andesite (49 to 58 wt. % SiO2) perfectly fits published experimental trends acquired on hydrous basalts at different crustal pressures, water concentrations and oxygen fugacities at subduction zones and can be accounted for by a fractional crystallization process where a bulk cumulate made of plagioclase, olivine, clinopyroxene and

  13. Modeling the Hydrological Cycle in the Atmosphere of Mars: Influence of a Bimodal Size Distribution of Aerosol Nucleation Particles

    Science.gov (United States)

    Shaposhnikov, Dmitry S.; Rodin, Alexander V.; Medvedev, Alexander S.; Fedorova, Anna A.; Kuroda, Takeshi; Hartogh, Paul

    2018-02-01

    We present a new implementation of the hydrological cycle scheme into a general circulation model of the Martian atmosphere. The model includes a semi-Lagrangian transport scheme for water vapor and ice and accounts for microphysics of phase transitions between them. The hydrological scheme includes processes of saturation, nucleation, particle growth, sublimation, and sedimentation under the assumption of a variable size distribution. The scheme has been implemented into the Max Planck Institute Martian general circulation model and tested assuming monomodal and bimodal lognormal distributions of ice condensation nuclei. We present a comparison of the simulated annual variations, horizontal and vertical distributions of water vapor, and ice clouds with the available observations from instruments on board Mars orbiters. The accounting for bimodality of aerosol particle distribution improves the simulations of the annual hydrological cycle, including predicted ice clouds mass, opacity, number density, and particle radii. The increased number density and lower nucleation rates bring the simulated cloud opacities closer to observations. Simulations show a weak effect of the excess of small aerosol particles on the simulated water vapor distributions.

  14. Mesoporous ethanesilica materials with bimodal and trimodal pore-size distributions synthesised in the presence of cobalt ions

    Directory of Open Access Journals (Sweden)

    Alufelwi M. Tshavhungwe

    2010-07-01

    Full Text Available Mesoporous organosilica materials containing ethane groups in their framework were formed with two and three pore sizes (i.e. bimodal and trimodal pores when synthesised by the sol-gel method in the presence of cobalt ions. The compounds 1,2-bistrimethoxysilylethane and tetraethylorthosilicate were used as silicon sources and the reactions were done in the presence of a surfactant, which served as a template. Diffuse reflectance infrared Fourier transform spectroscopy revealed that organic functional groups were incorporated into the ethanesilica. Powder X-ray diffraction and nitrogen adsorption data indicated that the mesophase and textural properties (surface area, pore volume, pore diameter of the materials were dependent on the ageing temperature, the amount/ratio of silica precursors and cobalt ion incorporation. Secondary mesopores were drastically reduced by changing the ratio of silicon precursors.

  15. Twin Peaks? No Evidence of Bimodal Distribution of Outcomes in Clinical Trials of Nonsurgical Interventions for Spinal Pain: An Exploratory Analysis.

    Science.gov (United States)

    O'Connell, Neil E; Kamper, Steven J; Stevens, Matthew L; Li, Qiang

    2017-08-01

    The presence of bimodal outcome distributions has been used as a justification for conducting responder analyses, in addition to, or in place of analyses of the mean between-group difference, in clinical trials and systematic reviews of interventions for pain. The aim of this study was to investigate the distribution of participants' pain outcomes for evidence of bimodal distribution. We sourced data on participant outcomes from a convenience sample of 10 trials of nonsurgical interventions (exercise, manual therapy, medication) for spinal pain. We assessed normality using the Shapiro-Wilk test. When the Shapiro-Wilk test suggested non-normality we inspected distribution plots visually and attempted to classify them. To test whether responder analyses detected a meaningful number of additional patients experiencing substantial improvements we also calculated the risk difference and number needed to treat to benefit. We found no compelling evidence suggesting that outcomes were bimodally distributed for any of the intervention groups. Responder analysis would not meaningfully alter our interpretation of these data compared with the mean between group difference. Our findings suggest that bimodal distribution of outcomes should not be assumed in interventions for spinal pain and do not support the automatic prioritization of responder analysis over the between group difference in the evaluation of treatment effectiveness for pain. Secondary analysis of clinical trials of nonsurgical interventions for spinal pain found no evidence for bimodally distributed outcomes. The findings do not support the automatic prioritization of responder analyses over the average between group difference in the evaluation of treatment effectiveness for spinal pain. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  16. Cancerous epithelial cell lines shed extracellular vesicles with a bimodal size distribution that is sensitive to glutamine inhibition

    International Nuclear Information System (INIS)

    Santana, Steven Michael; Kirby, Brian J; Antonyak, Marc A; Cerione, Richard A

    2014-01-01

    Extracellular shed vesicles (ESVs) facilitate a unique mode of cell–cell communication wherein vesicle uptake can induce a change in the recipient cell's state. Despite the intensity of ESV research, currently reported data represent the bulk characterization of concentrated vesicle samples with little attention paid to heterogeneity. ESV populations likely represent diversity in mechanisms of formation, cargo and size. To better understand ESV subpopulations and the signaling cascades implicated in their formation, we characterize ESV size distributions to identify subpopulations in normal and cancerous epithelial cells. We have discovered that cancer cells exhibit bimodal ESV distributions, one small-diameter and another large-diameter population, suggesting that two mechanisms may govern ESV formation, an exosome population and a cancer-specific microvesicle population. Altered glutamine metabolism in cancer is thought to fuel cancer growth but may also support metastatic niche formation through microvesicle production. We describe the role of a glutaminase inhibitor, compound 968, in ESV production. We have discovered that inhibiting glutamine metabolism significantly impairs large-diameter microvesicle production in cancer cells. (paper)

  17. Cancerous epithelial cell lines shed extracellular vesicles with a bimodal size distribution that is sensitive to glutamine inhibition

    Science.gov (United States)

    Santana, Steven Michael; Antonyak, Marc A.; Cerione, Richard A.; Kirby, Brian J.

    2014-12-01

    Extracellular shed vesicles (ESVs) facilitate a unique mode of cell-cell communication wherein vesicle uptake can induce a change in the recipient cell's state. Despite the intensity of ESV research, currently reported data represent the bulk characterization of concentrated vesicle samples with little attention paid to heterogeneity. ESV populations likely represent diversity in mechanisms of formation, cargo and size. To better understand ESV subpopulations and the signaling cascades implicated in their formation, we characterize ESV size distributions to identify subpopulations in normal and cancerous epithelial cells. We have discovered that cancer cells exhibit bimodal ESV distributions, one small-diameter and another large-diameter population, suggesting that two mechanisms may govern ESV formation, an exosome population and a cancer-specific microvesicle population. Altered glutamine metabolism in cancer is thought to fuel cancer growth but may also support metastatic niche formation through microvesicle production. We describe the role of a glutaminase inhibitor, compound 968, in ESV production. We have discovered that inhibiting glutamine metabolism significantly impairs large-diameter microvesicle production in cancer cells.

  18. Modelling the Skinner Thesis : Consequences of a Lognormal or a Bimodal Resource Base Distribution

    NARCIS (Netherlands)

    Auping, W.L.

    2014-01-01

    The copper case is often used as an example in resource depletion studies. Despite these studies, several profound uncertainties remain in the system. One of these uncertainties is the distribution of copper grades in the lithosphere. The Skinner thesis promotes the idea that copper grades may be

  19. Identification of Ultrasonic Echolucent Carotid Plaques Using Discrete Fréchet Distance Between Bimodal Gamma Distributions.

    Science.gov (United States)

    Huang, Xiaowei; Zhang, Yanling; Meng, Long; Qian, Ming; Wong, Kelvin; Abbott, Derek; Zheng, Rongqin; Zheng, Hairong; Niu, Lili

    2017-03-01

    Echolucent carotid plaques are associated with acute cardiovascular and cerebrovascular events (ACCEs) in atherosclerotic patients. The aim of this study was to develop a computer-aided method for identifying echolucent plaques. A total of 315 ultrasound images of carotid plaques (105 echo-rich, 105 intermediate and 105 echolucent) collected from 153 patients were included in this study. A bimodal gamma distribution was proposed to model the pixel statistics in the gray scale images of plaques. The discrete Fréchet distance features (DFDFs) of each plaque were extracted based on the statistical model. The most discriminative features (MDFs) were obtained from DFDFs by linear discriminant analysis, and a k-nearestneighbor classifier was implemented for classification of different types of plaques. The classification accuracy of the three types of plaques using MDFs can reach 77.46%. When a receiver operating characteristics (ROC) curve was produced to identify echolucent plaques, the area under the curve was 0.831. Our results indicate potential feasibility of the method for identifying echolucent plaques based on DFDFs. Our method may potentially improve the ability of noninvasive ultrasonic examination in risk prediction of ACCEs for patients with plaques.

  20. High frequency compressional wave speed and attenuation measurements in water-saturated granular media with unimodal and bimodal grain size distributions.

    Science.gov (United States)

    Yang, Haesang; Seong, Woojae

    2018-02-01

    Compressional wave speed and attenuation were measured for water-saturated granular media employing five kinds of glass beads having unimodal and bimodal grain size distributions. Glass beads with grain sizes ranging from 250 to 850  μm were used for the acoustic measurements at a frequency range from 350 kHz to 1.1 MHz, which includes the transition range where scattering and non-scattering losses co-exist. The compressional wave speed and attenuation data are presented as a function of frequency and grain size distribution. The compressional wave speed and attenuation data show a variety of frequency dependencies for varying grain size distribution. The observed acoustic properties are investigated for the volume ratio of larger and smaller sized grains in the mixed bimodal media. Also, the measured results are compared with the empirical multiple scattering formula as a function of Rayleigh parameter  kd (product of wavenumber in the water k and mean grain diameter of the glass beads d) using weighted mean grain size. The measured results are also discussed, focusing on the geophysical difference between unimodal and bimodal mixed grains.

  1. Possible detection of a bimodal cloud distribution in the atmosphere of HAT-P-32 A b from multiband photometry

    Science.gov (United States)

    Tregloan-Reed, J.; Southworth, J.; Mancini, L.; Mollière, P.; Ciceri, S.; Bruni, I.; Ricci, D.; Ayala-Loera, C.; Henning, T.

    2018-03-01

    We present high-precision photometry of eight separate transit events in the HAT-P-32 planetary system. One transit event was observed simultaneously by two telescopes of which one obtained a simultaneous multiband light curve in three optical bands, giving a total of 11 transit light curves. Due to the filter selection and in conjunction with using the defocused photometry technique, we were able to obtain an extremely high-precision, ground-based transit in the u band (350 nm), with an rms scatter of ≈1 mmag. All 11 transits were modelled using PRISM and GEMC, and the physical properties of the system calculated. We find the mass and radius of the host star to be 1.182 ± 0.041 M⊙ and 1.225 ± 0.015 R⊙, respectively. For the planet, we find a mass of 0.80 ± 0.14 MJup, a radius of 1.807 ± 0.022 RJup, and a density of 0.126 ± 0.023 ρJup. These values are consistent with those found in the literature. We also obtain a new orbital ephemeris for the system T0 = BJD/TDB 2 454 420.447187(96) + 2.15000800(10) × E. We measured the transmission spectrum of HAT-P-32 A b and compared it to theoretical transmission spectra. Our results indicate a bimodal cloud particle distribution consisting of Rayleigh-like haze and grey absorbing cloud particles within the atmosphere of HAT-P-32 A b.

  2. Bimodal distribution of the magnetic dipole moment in nanoparticles with a monomodal distribution of the physical size

    NARCIS (Netherlands)

    van Rijssel, Jozef; Kuipers, Bonny W M; Erne, Ben

    2015-01-01

    High-frequency applications of magnetic nanoparticles, such as therapeutic hyperthermia and magnetic particle imaging, are sensitive to nanoparticle size and dipole moment. Usually, it is assumed that magnetic nanoparticles with a log-normal distribution of the physical size also have a log-normal

  3. Comparative DNA isolation behaviours of silica and polymer based sorbents in batch fashion: monodisperse silica microspheres with bimodal pore size distribution as a new sorbent for DNA isolation.

    Science.gov (United States)

    Günal, Gülçin; Kip, Çiğdem; Eda Öğüt, S; İlhan, Hasan; Kibar, Güneş; Tuncel, Ali

    2018-02-01

    Monodisperse silica microspheres with bimodal pore-size distribution were proposed as a high performance sorbent for DNA isolation in batch fashion under equilibrium conditions. The proposed sorbent including both macroporous and mesoporous compartments was synthesized 5.1 μm in-size, by a "staged shape templated hydrolysis and condensation method". Hydrophilic polymer based sorbents were also obtained in the form of monodisperse-macroporous microspheres ca 5.5 μm in size, with different functionalities, by a developed "multi-stage microsuspension copolymerization" technique. The batch DNA isolation performance of proposed material was comparatively investigated using polymer based sorbents with similar morphologies. Among all sorbents tried, the best DNA isolation performance was achieved with the monodisperse silica microspheres with bimodal pore size distribution. The collocation of interconnected mesoporous and macroporous compartments within the monodisperse silica microspheres provided a high surface area and reduced the intraparticular mass transfer resistance and made easier both the adsorption and desorption of DNA. Among the polymer based sorbents, higher DNA isolation yields were achieved with the monodisperse-macroporous polymer microspheres carrying trimethoxysilyl and quaternary ammonium functionalities. However, batch DNA isolation performances of polymer based sorbents were significantly lower with respect to the silica microspheres.

  4. Primary particle diameter differentiation and bimodality identification by five analytical methods using gold nanoparticle size distributions synthesized by pulsed laser ablation in liquids

    Science.gov (United States)

    Letzel, Alexander; Gökce, Bilal; Menzel, Andreas; Plech, Anton; Barcikowski, Stephan

    2018-03-01

    For a known material, the size distribution of a nanoparticle colloid is a crucial parameter that defines its properties. However, measured size distributions are not easy to interpret as one has to consider weighting (e.g. by light absorption, scattering intensity, volume, surface, number) and the way size information was gained. The radius of a suspended nanoparticle can be given as e.g. sphere equivalent, hydrodynamic, Feret or radius of gyration. In this study, gold nanoparticles in water are synthesized by pulsed-laser ablation (LAL) and fragmentation (LFL) in liquids and characterized by various techniques (scanning transmission electron microscopy (STEM), small-angle X-ray scattering (SAXS), analytical disc centrifugation (ADC), dynamic light scattering (DLS) and UV-vis spectroscopy with Mie-Gans Theory) to study the comparability of different analytical techniques and determine the method that is preferable for a given task related to laser-generated nanoparticles. In particular, laser-generated colloids are known to be bimodal and/or polydisperse, but bimodality is sometimes not analytically resolved in literature. In addition, frequently reported small size shifts of the primary particle mode around 10 nm needs evaluation of its statistical significance related to the analytical method. Closely related to earlier studies on SAXS, different colloids in defined proportions are mixed and their size as a function of the nominal mixing ratio is analyzed. It is found that the derived particle size is independent of the nominal mixing ratio if the colloid size fractions do not overlap considerably. Conversely, the obtained size for colloids with overlapping size fractions strongly depends on the nominal mixing ratio since most methods cannot distinguish between such fractions. Overall, SAXS and ADC are very accurate methods for particle size analysis. Further, the ability of different methods to determine the nominal mixing ratio of sizes fractions is studied

  5. Unmixing detrital geochronology age distributions

    Science.gov (United States)

    Sundell, Kurt E.; Saylor, Joel E.

    2017-08-01

    Despite recent advances in quantitative methods of detrital provenance analysis, there is currently no widely accepted method of unmixing detrital geochronology age distributions. We developed a model that determines mixing proportions for source samples through inverse Monte Carlo modeling, wherein mixed samples are compared to randomly generated combinations of source distributions, and a range of best mixing proportions are retained. Results may then be used to constrain a forward optimization routine to find a single best-fit mixture. Quantitative comparison is based on the Kolmogorov-Smirnov (KS) test D statistic and Kuiper test V statistic for cumulative distribution functions, and the Cross-correlation coefficient for finite mixture distributions (probability density plots or kernel density estimates). We demonstrate the capacity of this model through a series of tests on synthetic data, and published empirical data from North America mixed in known proportions; this proof-of-concept testing shows the model is capable of accurately unmixing highly complex distributions. We apply the model to two published empirical data sets mixed in unknown proportions from Colombia and central China. Neither example yields perfect model fits, which provides a cautionary note of potentially inadequate characterization of source and/or mixed samples, and highlights the importance of such characterization for accurate interpretation of sediment provenance. Sample size appears to be a major control on mixture model results; small (n < 100) samples may lead to misinterpretation. The model is available as a MATLAB-based stand-alone executable (.exe file) graphical user interface.

  6. Application of bimodal distribution to the detection of changes in uranium concentration in drinking water collected by random daytime sampling method from a large water supply zone.

    Science.gov (United States)

    Garboś, Sławomir; Święcicka, Dorota

    2015-11-01

    The random daytime (RDT) sampling method was used for the first time in the assessment of average weekly exposure to uranium through drinking water in a large water supply zone. Data set of uranium concentrations determined in 106 RDT samples collected in three runs from the water supply zone in Wroclaw (Poland), cannot be simply described by normal or log-normal distributions. Therefore, a numerical method designed for the detection and calculation of bimodal distribution was applied. The extracted two distributions containing data from the summer season of 2011 and the winter season of 2012 (nI=72) and from the summer season of 2013 (nII=34) allowed to estimate means of U concentrations in drinking water: 0.947 μg/L and 1.23 μg/L, respectively. As the removal efficiency of uranium during applied treatment process is negligible, the effect of increase in uranium concentration can be explained by higher U concentration in the surface-infiltration water used for the production of drinking water. During the summer season of 2013, heavy rains were observed in Lower Silesia region, causing floods over the territory of the entire region. Fluctuations in uranium concentrations in surface-infiltration water can be attributed to releases of uranium from specific sources - migration from phosphate fertilizers and leaching from mineral deposits. Thus, exposure to uranium through drinking water may increase during extreme rainfall events. The average chronic weekly intakes of uranium through drinking water, estimated on the basis of central values of the extracted normal distributions, accounted for 3.2% and 4.1% of tolerable weekly intake. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Significant Corrosion Resistance in an Ultrafine-Grained Al6063 Alloy with a Bimodal Grain-Size Distribution through a Self-Anodic Protection Mechanism

    Directory of Open Access Journals (Sweden)

    Mahdieh Shakoori Oskooie

    2016-12-01

    Full Text Available The bimodal microstructures of Al6063 consisting of 15, 30, and 45 vol. % coarse-grained (CG bands within the ultrafine-grained (UFG matrix were synthesized via blending of high-energy mechanically milled powders with unmilled powders followed by hot powder extrusion. The corrosion behavior of the bimodal specimens was assessed by means of polarization, steady-state cyclic polarization and impedance tests, whereas their microstructural features and corrosion products were examined using optical microscopy (OM, scanning transmission electron microscopy (STEM, field emission scanning electron microscopy (FE-SEM, electron backscattered diffraction (EBSD, energy dispersive spectroscopy (EDS, and X-ray diffraction (XRD techniques. The bimodal Al6063 containing 15 vol. % CG phase exhibits the highest corrosion resistance among the bimodal microstructures and even superior electrochemical behavior compared with the plain UFG and CG materials in the 3.5% NaCl solution. The enhanced corrosion resistance is attributed to the optimum cathode to anode surface area ratio that gives rise to the formation of an effective galvanic couple between CG areas and the UFG matrix. The operational galvanic coupling leads to the domination of a “self-anodic protection system” on bimodal microstructure and consequently forms a uniform thick protective passive layer over it. In contrast, the 45 vol. % CG bimodal specimen shows the least corrosion resistance due to the catastrophic galvanic corrosion in UFG regions. The observed results for UFG Al6063 suggest that metallurgical tailoring of the grain structure in terms of bimodal microstructures leads to simultaneous enhancement in the electrochemical behavior and mechanical properties of passivable alloys that are usually inversely correlated. The mechanism of self-anodic protection for passivable metals with bimodal microstructures is discussed here for the first time.

  8. Beta-binomial regression and bimodal utilization.

    Science.gov (United States)

    Liu, Chuan-Fen; Burgess, James F; Manning, Willard G; Maciejewski, Matthew L

    2013-10-01

    To illustrate how the analysis of bimodal U-shaped distributed utilization can be modeled with beta-binomial regression, which is rarely used in health services research. Veterans Affairs (VA) administrative data and Medicare claims in 2001-2004 for 11,123 Medicare-eligible VA primary care users in 2000. We compared means and distributions of VA reliance (the proportion of all VA/Medicare primary care visits occurring in VA) predicted from beta-binomial, binomial, and ordinary least-squares (OLS) models. Beta-binomial model fits the bimodal distribution of VA reliance better than binomial and OLS models due to the nondependence on normality and the greater flexibility in shape parameters. Increased awareness of beta-binomial regression may help analysts apply appropriate methods to outcomes with bimodal or U-shaped distributions. © Health Research and Educational Trust.

  9. Reactive Sintering of Bimodal WC-Co Hardmetals

    OpenAIRE

    Marek Tarraste; Kristjan Juhani; Jüri Pirso; Mart Viljus

    2015-01-01

    Bimodal WC-Co hardmetals were produced using novel technology - reactive sintering. Milled and activated tungsten and graphite powders were mixed with commercial coarse grained WC-Co powder and then sintered. The microstructure of produced materials was free of defects and consisted of evenly distributed coarse and fine tungsten carbide grains in cobalt binder. The microstructure, hardness and fracture toughness of reactive sintered bimodal WC-Co hardmetals is exhibited. Developed bimodal har...

  10. New bimodal pore catalysts for Fischer-Tropsch synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Shinoda, Misao; Zhang, Yi; Yoneyama, Yoshiharu; Hasegawa, Kiyoshi; Tsubaki, Noritatsu [Department of Material System and Life Science, School of Engineering, Toyama University, Gofuku 3190, Toyama 930-8555 (Japan)

    2004-11-15

    A simple preparation method of bimodal pore supports was developed by introducing SiO{sub 2} or ZrO{sub 2} sols into large pores of SiO{sub 2} gel pellets directly. The pores of the obtained bimodal pore supports distributed distinctly as two kinds of main pores. On the other hand, the increased BET surface area and decreased pore volume, compared to those of original silica gel, indicated that the obtained bimodal pore supports formed according to the designed route. The obtained bimodal pore supports were applied in liquid-phase Fischer-Tropsch synthesis (FTS) where cobalt was supported. The bimodal pore catalysts presented the best reaction performance in liquid-phase Fischer-Tropsch synthesis (FTS) as higher reaction rate and lower methane selectivities, because the spatial promotional effect of bimodal pore structure and chemical effect of the porous zirconia behaved inside the large pores of original silica gel.

  11. Bimodal Nuclear Thermal Rocket Analysis Developments

    Science.gov (United States)

    Belair, Michael; Lavelle, Thomas; Saimento, Charles; Juhasz, Albert; Stewart, Mark

    2014-01-01

    Nuclear thermal propulsion has long been considered an enabling technology for human missions to Mars and beyond. One concept of operations for these missions utilizes the nuclear reactor to generate electrical power during coast phases, known as bimodal operation. This presentation focuses on the systems modeling and analysis efforts for a NERVA derived concept. The NERVA bimodal operation derives the thermal energy from the core tie tube elements. Recent analysis has shown potential temperature distributions in the tie tube elements that may limit the thermodynamic efficiency of the closed Brayton cycle used to generate electricity with the current design. The results of this analysis are discussed as well as the potential implications to a bimodal NERVA type reactor.

  12. The exponential age distribution and the Pareto firm size distribution

    OpenAIRE

    Coad, Alex

    2008-01-01

    Recent work drawing on data for large and small firms has shown a Pareto distribution of firm size. We mix a Gibrat-type growth process among incumbents with an exponential distribution of firm’s age, to obtain the empirical Pareto distribution.

  13. Language choice in bimodal bilingual development

    Directory of Open Access Journals (Sweden)

    Diane eLillo-Martin

    2014-10-01

    Full Text Available Bilingual children develop sensitivity to the language used by their interlocutors at an early age, reflected in differential use of each language by the child depending on their interlocutor. Factors such as discourse context and relative language dominance in the community may mediate the degree of language differentiation in preschool age children.Bimodal bilingual children, acquiring both a sign language and a spoken language, have an even more complex situation. Their Deaf parents vary considerably in access to the spoken language. Furthermore, in addition to code-mixing and code-switching, they use code-blending – expressions in both speech and sign simultaneously – an option uniquely available to bimodal bilinguals. Code-blending is analogous to code-switching sociolinguistically, but is also a way to communicate without suppressing one language. For adult bimodal bilinguals, complete suppression of the non-selected language is cognitively demanding. We expect that bimodal bilingual children also find suppression difficult, and use blending rather than suppression in some contexts. We also expect relative community language dominance to be a factor in children’s language choices.This study analyzes longitudinal spontaneous production data from four bimodal bilingual children and their Deaf and hearing interlocutors. Even at the earliest observations, the children produced more signed utterances with Deaf interlocutors and more speech with hearing interlocutors. However, while three of the four children produced >75% speech alone in speech target sessions, they produced <25% sign alone in sign target sessions. All four produced bimodal utterances in both, but more frequently in the sign sessions, potentially because they find suppression of the dominant language more difficult.Our results indicate that these children are sensitive to the language used by their interlocutors, while showing considerable influence from the dominant

  14. Corredor Bimodal Cafetero

    OpenAIRE

    Duque Escobar, Gonzalo

    2015-01-01

    El Corredor Bimodal Cafetero es un proyecto de infraestructura estratégica que articula la Hidrovía del Magdalena con el Corredor Férreo del río Cauca, inscrito en el Plan Nacional de Desarrollo 2014/2018 y financiable con la salida de 30 mil toneladas diarias de carbón andino a la cuenca del Pacífico. Incluye el Túnel Cumanday para cruzar la Cordillera Central, el Ferrocarril Cafetero de 150 km y 3% de pendiente entre La Dorada y el Km 41, y la Transversal Cafetera de 108 km para una vía de...

  15. Roles of factorial noise in inducing bimodal gene expression

    Science.gov (United States)

    Liu, Peijiang; Yuan, Zhanjiang; Huang, Lifang; Zhou, Tianshou

    2015-06-01

    Some gene regulatory systems can exhibit bimodal distributions of mRNA or protein although the deterministic counterparts are monostable. This noise-induced bimodality is an interesting phenomenon and has important biological implications, but it is unclear how different sources of expression noise (each source creates so-called factorial noise that is defined as a component of the total noise) contribute separately to this stochastic bimodality. Here we consider a minimal model of gene regulation, which is monostable in the deterministic case. Although simple, this system contains factorial noise of two main kinds: promoter noise due to switching between gene states and transcriptional (or translational) noise due to synthesis and degradation of mRNA (or protein). To better trace the roles of factorial noise in inducing bimodality, we also analyze two limit models, continuous and adiabatic approximations, apart from the exact model. We show that in the case of slow gene switching, the continuous model where only promoter noise is considered can exhibit bimodality; in the case of fast switching, the adiabatic model where only transcriptional or translational noise is considered can also exhibit bimodality but the exact model cannot; and in other cases, both promoter noise and transcriptional or translational noise can cooperatively induce bimodality. Since slow gene switching and large protein copy numbers are characteristics of eukaryotic cells, whereas fast gene switching and small protein copy numbers are characteristics of prokaryotic cells, we infer that eukaryotic stochastic bimodality is induced mainly by promoter noise, whereas prokaryotic stochastic bimodality is induced primarily by transcriptional or translational noise.

  16. Dynamical and statistical bimodality in nuclear fragmentation

    Science.gov (United States)

    Mallik, S.; Chaudhuri, G.; Gulminelli, F.

    2018-02-01

    The origin of bimodal behavior in the residue distribution experimentally measured in heavy ion reactions is reexamined using Boltzmann-Uehling-Uhlenbeck simulations. We suggest that, depending on the incident energy and impact parameter of the reaction, both entrance channel and exit channel effects can be at the origin of the observed behavior. Specifically, fluctuations in the reaction mechanism induced by fluctuations in the collision rate, as well as thermal bimodality directly linked to the nuclear liquid-gas phase transition, are observed in our simulations. Both phenomenologies were previously proposed in the literature but presented as incompatible and contradictory interpretations of the experimental measurements. These results indicate that heavy ion collisions at intermediate energies can be viewed as a powerful tool to study both bifurcations induced by out-of-equilibrium critical phenomena, as well as finite-size precursors of thermal phase transitions.

  17. Bimodal metal micro-nanopowders for powder injection molding

    Science.gov (United States)

    Pervikov, Aleksandr; Rodkevich, Nikolay; Glazkova, Elena; Lerner, Marat

    2017-12-01

    The paper studies a bimodal metal powder composition designed to prepare feedstock for powder injection molding, as well as microstructure and porosity of sintered pats. Two kinds of metal powder compositions are used, in particular, a mixture of micro- and nanopowders and a bimodal powder prepared with dispersion of steel wire. The feedstock is prepared by mixing a bimodal metal powder composition with acetylacetone and paraffin wax. The microstructure of the debound parts is observed by scanning electron microscopy. The sintered parts are characterized by density measurements and metallographic analysis. The technique of the metal powder composition proves to affect the characteristics of sintered parts. Nanoparticles are shown in the interstitial spaces among the microparticles upon mixing micro- and nanopowders, but the regular distribution of nanoparticles on the surface of microparticles is observed in the bimodal powder providing the reduction of the porosity of sintered parts and increasing the density to the proper density of steel.

  18. Reactive Sintering of Bimodal WC-Co Hardmetals

    Directory of Open Access Journals (Sweden)

    Marek Tarraste

    2015-09-01

    Full Text Available Bimodal WC-Co hardmetals were produced using novel technology - reactive sintering. Milled and activated tungsten and graphite powders were mixed with commercial coarse grained WC-Co powder and then sintered. The microstructure of produced materials was free of defects and consisted of evenly distributed coarse and fine tungsten carbide grains in cobalt binder. The microstructure, hardness and fracture toughness of reactive sintered bimodal WC-Co hardmetals is exhibited. Developed bimodal hardmetal has perspective for demanding wear applications for its increased combined hardness and toughness. Compared to coarse material there is only slight decrease in fracture toughness (K1c is 14.7 for coarse grained and 14.4 for bimodal, hardness is increased from 1290 to 1350 HV units.DOI: http://dx.doi.org/10.5755/j01.ms.21.3.7511

  19. Stellar Rotation with Kepler and Gaia: Evidence for a Bimodal Star Formation History

    Science.gov (United States)

    Davenport, James

    2018-01-01

    Kepler stars with rotation periods measured via starspot modulations in their light curves have been matched against the astrometric data from Gaia Data Release 1. A total of 1,299 bright rotating stars were recovered, most with temperatures hotter than 5000 K. From these, 894 were selected as being near the main sequence. These main sequence stars show a bimodality in their rotation period distribution, centered around a ~600 Myr rotation-isochrone. This feature matches the bimodal period distribution found in cooler stars with Kepler, but was previously undetected for solar-type stars due to sample contamination by subgiant and binary stars. A tenuous connection between the rotation period and total proper motion is found, suggesting the period bimodality is due to the age distribution of stars within 300pc of the Sun, rather than a phase of rapid angular momentum loss. I will discuss how the combination of Kepler/K2/TESS with Gaia will enable us to map the star formation history of our galactic neighborhood.

  20. The role of the bimodal distribution of ultra-fine silicon phase and nano-scale V-phase (AlSi2Sc2) on spark plasma sintered hypereutectic Al–Si–Sc alloys

    International Nuclear Information System (INIS)

    Raghukiran, Nadimpalli; Kumar, Ravi

    2016-01-01

    Hypereutectic Al–Si and Al–Si–Sc alloys were spark plasma sintered from corresponding gas-atomized powders. The microstructures of the Al–Si and Al–Si–Sc alloys possessed remarkably refined silicon particles in the size range of 0.38–3.5 µm and 0.35–1.16 µm respectively in contrast to the silicon particles of size greater than 100 µm typically found in conventionally cast alloys. All the sintered alloys exhibited significant ductility of as high as 85% compressive strain without failure even with the presence of relatively higher weight fraction of the brittle silicon phase. Moreover, the Al–Si–Sc alloys have shown appreciable improvement in the compressive strength over their binary counterparts due to the presence of intermetallic compound AlSi 2 Sc 2 of size 10–20 nm distributed uniformly in the matrix of those alloys. The dry sliding pin-on-disc wear tests showed improvement in the wear performance of the sintered alloys with increase in silicon content in the alloys. Further, the Al–Si–Sc ternary alloys with relatively lesser silicon content exhibited appreciable improvement in the wear resistance over their binary counterparts. The Al–Si–Sc alloys with bimodal distribution of the strengthening phases consisting of ultra-fine (sub-micron size) silicon particles and the nano-scale AlSi 2 Sc 2 improved the strength and wear properties of the alloys while retaining significant amount of ductility.

  1. Patent foramen ovale in a large population of ischemic stroke patients: diagnosis, age distribution, gender, and race.

    Science.gov (United States)

    Gupta, Vishal; Yesilbursa, Dilek; Huang, Wen Ying; Aggarwal, Kul; Gupta, Vijaya; Gomez, Camilo; Patel, Vinod; Miller, Andrew P; Nanda, Navin C

    2008-02-01

    Patent foramen ovale (PFO) is a well-recognized risk factor for ischemic strokes. The true prevalence of PFO among stroke patients is still under debate. Transesophageal echocardiography (TEE) is the "gold standard" in diagnosing PFO but the physiology requires right-to-left atrial shunting. In this report, we evaluate the prevalence of PFO in a diverse group of ischemic stroke patients studied by TEE. TEE of 1,663 ischemic stroke patients were reviewed for cardiac source of embolism, including PFO and atrial septal aneurysm (ASA). Agitated saline bubble injection was performed to look for right to left atrial shunting. Success of maneuvers to elevate right atrial pressure (RAP) was noted by looking at the atrial septal bulge. Among 1,435 ischemic stroke patients analyzed, the presence or absence of PFO could not be determined in 32.1% because bulging of the septum could not be demonstrated in patients with negative contrast study despite aggressive maneuvers to elevate RAP. Of the remaining 974 patients, 294 patients (30.2%) had a PFO. The mean age was 61.5 years in both groups, with a bimodal distribution of PFO and the highest prevalence occurring in gender or racial difference in the prevalence of PFO, but there was a bimodal distribution in prevalence with age.

  2. Optical properties of bimodally distributed InAs quantum dots grown on digital AlAs0.56Sb0.44 matrix for use in intermediate band solar cells

    Science.gov (United States)

    Debnath, Mukul C.; Liang, Baolai; Laghumavarapu, Ramesh B.; Wang, Guodong; Das, Aparna; Juang, Bor-Chau; Huffaker, Diana L.

    2017-06-01

    High-quality InAs quantum dots (QDs) with nominal thicknesses of 5.0-8.0 monolayers were grown on a digital AlAs0.56Sb0.44 matrix lattice-matched to the InP(001) substrate. All QDs showed bimodal size distribution, and their optical properties were investigated by photoluminescence (PL) and time-resolved PL measurements. Power dependent PL exhibited a linear relationship between the peak energy and the cube root of the excitation power for both the small QD family (SQDF) and the large QD family (LQDF), which is attributed to the type-II transition. The PL intensity, peak energy, and carrier lifetime of SQDF and LQDF showed very sensitive at high temperature. Above 125 K, the PL intensity ratio increased continuously between LQDF and SQDF, the peak energy shifted anomalously in SQDF, and the longer carrier radiative lifetime (≥3.0 ns at 77 K) reduced rapidly in SQDF and slowly in LQDF. These results are ascribed to thermally activated carrier escape from SQDF into the wetting layer, which then relaxed into LQDF with low-localized energy states.

  3. 'Bi-modal' isoscalar giant dipole strength in 58Ni

    International Nuclear Information System (INIS)

    Nayak, B.K.; Garg, U.; Hedden, M.; Koss, M.; Li, T.; Liu, Y.; Madhusudhana Rao, P.V.; Zhu, S.; Itoh, M.; Sakaguchi, H.; Takeda, H.; Uchida, M.; Yasuda, Y.; Yosoi, M.; Fujimura, H.; Fujiwara, M.; Hara, K.; Kawabata, T.; Akimune, H.; Harakeh, M.N.

    2006-01-01

    The strength distribution of the isoscalar giant dipole resonance (ISGDR) in 58 Ni has been obtained over the energy range 10.5-49.5 MeV via extreme forward angle scattering (including 0 deg.) of 386 MeV α particles. We observe a 'bi-modal' E1 strength distribution for the first time in an A<90 nucleus. The observed ISGDR strength distribution is in reasonable agreement with the predictions of a recent RPA calculation

  4. Distribution of age at menopause in two Danish samples

    DEFF Research Database (Denmark)

    Boldsen, J L; Jeune, B

    1990-01-01

    We analyzed the distribution of reported age at natural menopause in two random samples of Danish women (n = 176 and n = 150) to determine the shape of the distribution and to disclose any possible trends in the distribution parameters. It was necessary to correct the frequencies of the reported...... ages for the effect of differing ages at reporting. The corrected distribution of age at menopause differs from the normal distribution in the same way in both samples. Both distributions could be described by a mixture of two normal distributions. It appears that most of the parameters of the normal...... distribution mixtures remain unchanged over a 50-year time lag. The position of the distribution, that is, the mean age at menopause, however, increases slightly but significantly....

  5. Distribution of age at menopause in two Danish samples

    DEFF Research Database (Denmark)

    Boldsen, J L; Jeune, B

    1990-01-01

    ages for the effect of differing ages at reporting. The corrected distribution of age at menopause differs from the normal distribution in the same way in both samples. Both distributions could be described by a mixture of two normal distributions. It appears that most of the parameters of the normal......We analyzed the distribution of reported age at natural menopause in two random samples of Danish women (n = 176 and n = 150) to determine the shape of the distribution and to disclose any possible trends in the distribution parameters. It was necessary to correct the frequencies of the reported...... distribution mixtures remain unchanged over a 50-year time lag. The position of the distribution, that is, the mean age at menopause, however, increases slightly but significantly....

  6. Human and mouse switch-like genes share common transcriptional regulatory mechanisms for bimodality

    Directory of Open Access Journals (Sweden)

    Tozeren Aydin

    2008-12-01

    Full Text Available Abstract Background Gene expression is controlled over a wide range at the transcript level through complex interplay between DNA and regulatory proteins, resulting in profiles of gene expression that can be represented as normal, graded, and bimodal (switch-like distributions. We have previously performed genome-scale identification and annotation of genes with switch-like expression at the transcript level in mouse, using large microarray datasets for healthy tissue, in order to study the cellular pathways and regulatory mechanisms involving this class of genes. We showed that a large population of bimodal mouse genes encoding for cell membrane and extracellular matrix proteins is involved in communication pathways. This study expands on previous results by annotating human bimodal genes, investigating their correspondence to bimodality in mouse orthologs and exploring possible regulatory mechanisms that contribute to bimodality in gene expression in human and mouse. Results Fourteen percent of the human genes on the HGU133A array (1847 out of 13076 were identified as bimodal or switch-like. More than 40% were found to have bimodal mouse orthologs. KEGG pathways enriched for bimodal genes included ECM-receptor interaction, focal adhesion, and tight junction, showing strong similarity to the results obtained in mouse. Tissue-specific modes of expression of bimodal genes among brain, heart, and skeletal muscle were common between human and mouse. Promoter analysis revealed a higher than average number of transcription start sites per gene within the set of bimodal genes. Moreover, the bimodal gene set had differentially methylated histones compared to the set of the remaining genes in the genome. Conclusion The fact that bimodal genes were enriched within the cell membrane and extracellular environment make these genes as candidates for biomarkers for tissue specificity. The commonality of the important roles bimodal genes play in tissue

  7. A HYPOTHESIS FOR THE COLOR BIMODALITY OF JUPITER TROJANS

    International Nuclear Information System (INIS)

    Wong, Ian; Brown, Michael E.

    2016-01-01

    One of the most enigmatic and hitherto unexplained properties of Jupiter Trojans is their bimodal color distribution. This bimodality is indicative of two sub-populations within the Trojans, which have distinct size distributions. In this paper, we present a simple, plausible hypothesis for the origin and evolution of the two Trojan color sub-populations. In the framework of dynamical instability models of early solar system evolution, which suggest a common primordial progenitor population for both Trojans and Kuiper Belt objects, we use observational constraints to assert that the color bimodalities evident in both minor body populations developed within the primordial population prior to the onset of instability. We show that, beginning with an initial composition of rock and ices, location-dependent volatile loss through sublimation in this primordial population could have led to sharp changes in the surface composition with heliocentric distance. We propose that the depletion or retention of H 2 S ice on the surface of these objects was the key factor in creating an initial color bimodality. Objects that retained H 2 S on their surfaces developed characteristically redder colors upon irradiation than those that did not. After the bodies from the primordial population were scattered and emplaced into their current positions, they preserved this primordial color bimodality to the present day. We explore predictions of the volatile loss model—in particular, the effect of collisions within the Trojan population on the size distributions of the two sub-populations—and propose further experimental and observational tests of our hypothesis.

  8. A HYPOTHESIS FOR THE COLOR BIMODALITY OF JUPITER TROJANS

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Ian; Brown, Michael E., E-mail: iwong@caltech.edu [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States)

    2016-10-01

    One of the most enigmatic and hitherto unexplained properties of Jupiter Trojans is their bimodal color distribution. This bimodality is indicative of two sub-populations within the Trojans, which have distinct size distributions. In this paper, we present a simple, plausible hypothesis for the origin and evolution of the two Trojan color sub-populations. In the framework of dynamical instability models of early solar system evolution, which suggest a common primordial progenitor population for both Trojans and Kuiper Belt objects, we use observational constraints to assert that the color bimodalities evident in both minor body populations developed within the primordial population prior to the onset of instability. We show that, beginning with an initial composition of rock and ices, location-dependent volatile loss through sublimation in this primordial population could have led to sharp changes in the surface composition with heliocentric distance. We propose that the depletion or retention of H{sub 2}S ice on the surface of these objects was the key factor in creating an initial color bimodality. Objects that retained H{sub 2}S on their surfaces developed characteristically redder colors upon irradiation than those that did not. After the bodies from the primordial population were scattered and emplaced into their current positions, they preserved this primordial color bimodality to the present day. We explore predictions of the volatile loss model—in particular, the effect of collisions within the Trojan population on the size distributions of the two sub-populations—and propose further experimental and observational tests of our hypothesis.

  9. Bimodal immune activation in psoriasis.

    Science.gov (United States)

    Christophers, E; Metzler, G; Röcken, M

    2014-01-01

    Psoriasis is an immune-regulated skin disease with various clinical subtypes and disease activities. The majority of patients present with predominantly stable plaques. At the onset of new lesions, plaque-type psoriasis frequently demonstrates pin-sized and highly inflammatory papules sometimes with an inflammatory border. The histopathology of initial psoriasis differs from stable plaque-type psoriasis. Early lesions demonstrate innate immune cells with neutrophils, degranulating mast cells and macrophages. These are followed by interleukin (IL)-1-dependent T helper (Th)17 cells, finally resulting in the Th1-dominated immunopathology of stable plaque-type psoriasis, where mononuclear cells predominate with interspersed neutrophilic (Munro) microabscesses. These features suggest a bimodal immune pathway where alternate activation of either innate (autoinflammatory) or adaptive (autoimmune) immunity predominates. Neutrophilic infiltrations appear during early psoriasis with Munro abscesses. They are time limited and occur periodically, clinically best seen in linear nail pitting. These features strongly suggest a critical role for an IL-1-Th17-dominated autoinflammation in the initiation of psoriasis, followed by a Th1-dominated late-phase reaction. The concept of bimodal immune activation helps to explain results from therapeutic interventions that are variable and previously only partly understood. © 2013 British Association of Dermatologists.

  10. Impact of Zygosity on Bimodal Phenotype Distributions

    DEFF Research Database (Denmark)

    Holst-Hansen, Thomas; Abad, Elena; Muntasell, Aura

    2017-01-01

    . Here, we study this question making use of the natural genetic variability of human populations, which allows us to compare the expression profiles of a receptor protein in natural killer cells among donors infected with human cytomegalovirus with one or two copies of the allele. Crucially...

  11. BSA adsorption on bimodal PEO brushes

    NARCIS (Netherlands)

    Bosker, WTE; Iakovlev, PA; Norde, W; Stuart, Martien A. Cohen

    2005-01-01

    BSA adsorption onto bimodal PEO brushes at a solid surface was measured using optical reflectometry. Bimodal brushes consist of long (N = 770) and short (N = 48) PEO chains and were prepared on PS surfaces, applying mixtures of PS29-PEO48 and PS37-PEO770 block copolymers and using the

  12. BSA adsorption on bimodal PEO brushes

    NARCIS (Netherlands)

    Bosker, W.T.E.; Iakovlev, P.A.; Norde, W.; Cohen Stuart, M.A.

    2005-01-01

    BSA adsorption onto bimodal PEO brushes at a solid surface was measured using optical reflectometry. Bimodal brushes consist of long (N=770) and short (N=48) PEO chains and were prepared on PS surfaces, applying mixtures of PS 29-PEO48 and PS37-PEO770 block copolymers and using the Langmuir-Blodgett

  13. Age-distribution estimation for karst groundwater: Issues of parameterization and complexity in inverse modeling by convolution

    Science.gov (United States)

    Long, Andrew J.; Putnam, L.D.

    2009-01-01

    Convolution modeling is useful for investigating the temporal distribution of groundwater age based on environmental tracers. The framework of a quasi-transient convolution model that is applicable to two-domain flow in karst aquifers is presented. The model was designed to provide an acceptable level of statistical confidence in parameter estimates when only chlorofluorocarbon (CFC) and tritium (3H) data are available. We show how inverse modeling and uncertainty assessment can be used to constrain model parameterization to a level warranted by available data while allowing major aspects of the flow system to be examined. As an example, the model was applied to water from a pumped well open to the Madison aquifer in central USA with input functions of CFC-11, CFC-12, CFC-113, and 3H, and was calibrated to several samples collected during a 16-year period. A bimodal age distribution was modeled to represent quick and slow flow less than 50 years old. The effects of pumping and hydraulic head on the relative volumetric fractions of these domains were found to be influential factors for transient flow. Quick flow and slow flow were estimated to be distributed mainly within the age ranges of 0-2 and 26-41 years, respectively. The fraction of long-term flow (>50 years) was estimated but was not dateable. The different tracers had different degrees of influence on parameter estimation and uncertainty assessments, where 3H was the most critical, and CFC-113 was least influential.

  14. Nuclear bimodal new vision solar system missions

    International Nuclear Information System (INIS)

    Mondt, J.F.; Zubrin, R.M.

    1996-01-01

    This paper presents an analysis of the potential mission capability using space reactor bimodal systems for planetary missions. Missions of interest include the Main belt asteroids, Jupiter, Saturn, Neptune, and Pluto. The space reactor bimodal system, defined by an Air Force study for Earth orbital missions, provides 10 kWe power, 1000 N thrust, 850 s Isp, with a 1500 kg system mass. Trajectories to the planetary destinations were examined and optimal direct and gravity assisted trajectories were selected. A conceptual design for a spacecraft using the space reactor bimodal system for propulsion and power, that is capable of performing the missions of interest, is defined. End-to-end mission conceptual designs for bimodal orbiter missions to Jupiter and Saturn are described. All missions considered use the Delta 3 class or Atlas 2AS launch vehicles. The space reactor bimodal power and propulsion system offers both; new vision open-quote open-quote constellation close-quote close-quote type missions in which the space reactor bimodal spacecraft acts as a carrier and communication spacecraft for a fleet of microspacecraft deployed at different scientific targets and; conventional missions with only a space reactor bimodal spacecraft and its science payload. copyright 1996 American Institute of Physics

  15. The Development of Bimodal Bilingualism: Implications for Linguistic Theory.

    Science.gov (United States)

    Lillo-Martin, Diane; de Quadros, Ronice Müller; Pichler, Deborah Chen

    2016-01-01

    A wide range of linguistic phenomena contribute to our understanding of the architecture of the human linguistic system. In this paper we present a proposal dubbed Language Synthesis to capture bilingual phenomena including code-switching and 'transfer' as automatic consequences of the addition of a second language, using basic concepts of Minimalism and Distributed Morphology. Bimodal bilinguals, who use a sign language and a spoken language, provide a new type of evidence regarding possible bilingual phenomena, namely code-blending, the simultaneous production of (aspects of) a message in both speech and sign. We argue that code-blending also follows naturally once a second articulatory interface is added to the model. Several different types of code-blending are discussed in connection to the predictions of the Synthesis model. Our primary data come from children developing as bimodal bilinguals, but our proposal is intended to capture a wide range of bilingual effects across any language pair.

  16. A novel broadband bi-mode active frequency selective surface

    Science.gov (United States)

    Xu, Yang; Gao, Jinsong; Xu, Nianxi; Shan, Dongzhi; Song, Naitao

    2017-05-01

    A novel broadband bi-mode active frequency selective surface (AFSS) is presented in this paper. The proposed structure is composed of a periodic array of convoluted square patches and Jerusalem Crosses. According to simulation results, the frequency response of AFSS definitely exhibits a mode switch feature between band-pass and band-stop modes when the diodes stay in ON and OFF states. In order to apply a uniform bias to each PIN diode, an ingenious biasing network based on the extension of Wheatstone bridge is adopted in prototype AFSS. The test results are in good agreement with the simulation results. A further physical mechanism of the bi-mode AFSS is shown by contrasting the distribution of electric field on the AFSS patterns for the two working states.

  17. A novel broadband bi-mode active frequency selective surface

    Directory of Open Access Journals (Sweden)

    Yang Xu

    2017-05-01

    Full Text Available A novel broadband bi-mode active frequency selective surface (AFSS is presented in this paper. The proposed structure is composed of a periodic array of convoluted square patches and Jerusalem Crosses. According to simulation results, the frequency response of AFSS definitely exhibits a mode switch feature between band-pass and band-stop modes when the diodes stay in ON and OFF states. In order to apply a uniform bias to each PIN diode, an ingenious biasing network based on the extension of Wheatstone bridge is adopted in prototype AFSS. The test results are in good agreement with the simulation results. A further physical mechanism of the bi-mode AFSS is shown by contrasting the distribution of electric field on the AFSS patterns for the two working states.

  18. Irreducible complexity of iterated symmetric bimodal maps

    Directory of Open Access Journals (Sweden)

    J. P. Lampreia

    2005-01-01

    Full Text Available We introduce a tree structure for the iterates of symmetric bimodal maps and identify a subset which we prove to be isomorphic to the family of unimodal maps. This subset is used as a second factor for a ∗-product that we define in the space of bimodal kneading sequences. Finally, we give some properties for this product and study the ∗-product induced on the associated Markov shifts.

  19. Fragmentation versus stability in bimodal coalitions

    Science.gov (United States)

    Galam, Serge

    1996-02-01

    Competing bimodal coalitions among a group of actors are discussed. First, a model from political sciences is revisited. Most of the model statements are found not to be contained in the model. Second, a new coalition model is built. It accounts for local versus global alignment with respect to the joining of a coalition. The existence of two competing world coalitions is found to yield one unique stable distribution of actors. On the opposite a unique world leadership allows the emergence of unstable relationships. In parallel to regular actors which have a clear coalition choice, “neutral”, “frustrated” and “risky” actors are produced. The cold war organisation after world war II is shown to be rather stable. The emergence of a fragmentation process from eastern group disappearance is explained as well as continuing western group stability. Some hints are obtained about possible policies to stabilize world nation relationships. European construction is analyzed with respect to European stability. Chinese stability is also discussed.

  20. THE SLUGGS SURVEY: NGC 3115, A CRITICAL TEST CASE FOR METALLICITY BIMODALITY IN GLOBULAR CLUSTER SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Brodie, Jean P.; Conroy, Charlie; Arnold, Jacob A.; Romanowsky, Aaron J. [University of California Observatories and Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Usher, Christopher; Forbes, Duncan A. [Centre for Astrophysics and Supercomputing, Swinburne University, Hawthorn, VIC 3122 (Australia); Strader, Jay, E-mail: brodie@ucolick.org [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States)

    2012-11-10

    Due to its proximity (9 Mpc) and the strongly bimodal color distribution of its spectroscopically well-sampled globular cluster (GC) system, the early-type galaxy NGC 3115 provides one of the best available tests of whether the color bimodality widely observed in GC systems generally reflects a true metallicity bimodality. Color bimodality has alternatively been attributed to a strongly nonlinear color-metallicity relation reflecting the influence of hot horizontal-branch stars. Here, we couple Subaru Suprime-Cam gi photometry with Keck/DEIMOS spectroscopy to accurately measure GC colors and a CaT index that measures the Ca II triplet. We find the NGC 3115 GC system to be unambiguously bimodal in both color and the CaT index. Using simple stellar population models, we show that the CaT index is essentially unaffected by variations in horizontal-branch morphology over the range of metallicities relevant to GC systems (and is thus a robust indicator of metallicity) and confirm bimodality in the metallicity distribution. We assess the existing evidence for and against multiple metallicity subpopulations in early- and late-type galaxies and conclude that metallicity bi/multimodality is common. We briefly discuss how this fundamental characteristic links directly to the star formation and assembly histories of galaxies.

  1. Age distribution dynamics with stochastic jumps in mortality.

    Science.gov (United States)

    Calabrese, Salvatore; Porporato, Amilcare; Laio, Francesco; D'Odorico, Paolo; Ridolfi, Luca

    2017-11-01

    While deterministic age distribution models have been extensively studied and applied in various disciplines, little work has been devoted to understanding the role of stochasticity in birth and mortality terms. In this paper, we analyse a stochastic M'Kendrick-von Foerster equation in which jumps in mortality represent intense losses of population due to external events. We present explicit solutions for the probability density functions of the age distribution and the total population and for the temporal dynamics of their moments. We also derive the dynamics of the mean age of the population and its harmonic mean. The framework is then used to calculate the age distribution of salt in the soil root zone, where the accumulation of salt by atmospheric deposition is counteracted by plant uptake and by jump losses due to percolation events.

  2. Synergistic dual positive feedback loops established by molecular sequestration generate robust bimodal response.

    Science.gov (United States)

    Venturelli, Ophelia S; El-Samad, Hana; Murray, Richard M

    2012-11-27

    Feedback loops are ubiquitous features of biological networks and can produce significant phenotypic heterogeneity, including a bimodal distribution of gene expression across an isogenic cell population. In this work, a combination of experiments and computational modeling was used to explore the roles of multiple feedback loops in the bimodal, switch-like response of the Saccharomyces cerevisiae galactose regulatory network. Here, we show that bistability underlies the observed bimodality, as opposed to stochastic effects, and that two unique positive feedback loops established by Gal1p and Gal3p, which both regulate network activity by molecular sequestration of Gal80p, induce this bimodality. Indeed, systematically scanning through different single and multiple feedback loop knockouts, we demonstrate that there is always a concentration regime that preserves the system's bimodality, except for the double deletion of GAL1 and the GAL3 feedback loop, which exhibits a graded response for all conditions tested. The constitutive production rates of Gal1p and Gal3p operate as bifurcation parameters because variations in these rates can also abolish the system's bimodal response. Our model indicates that this second loss of bistability ensues from the inactivation of the remaining feedback loop by the overexpressed regulatory component. More broadly, we show that the sequestration binding affinity is a critical parameter that can tune the range of conditions for bistability in a circuit with positive feedback established by molecular sequestration. In this system, two positive feedback loops can significantly enhance the region of bistability and the dynamic response time.

  3. Bimodal condensation silicone elastomers as dielectric elastomers

    DEFF Research Database (Denmark)

    Yu, Liyun; Madsen, Frederikke Bahrt; Skov, Anne Ladegaard

    unimodal refers to that there is one polymer only in the system. As an alternative to unimodal networks there are the bimodal networks where two polymers with significantly different molecular weights are mixed with one crosslinker. [2]Silicone rubber can be divided into condensation type and addition type...... according to the curing reaction. The advantages of condensation silicones compared to addition are the relatively low cost, the curing rate largely being independent of temperature, the excellent adhesion, and the catalyst being nontoxic. [3]In this work, a series of bimodal condensation silicone...

  4. The prevalence and age distribution of peripheral pulmonary ...

    African Journals Online (AJOL)

    This autopsy-based study defined the prevalence and age distribution of peripheral pulmonary hamartomas in 47635 southern African miners examined between 1975 and 1988. The prevalence rate for white miners was 7,5/1000 and for black miners 1,1/1 000. When directly standardised to the white men in the general ...

  5. Can anchovy age structure be estimated from length distribution ...

    African Journals Online (AJOL)

    The analysis provides a new time-series of proportions-at-age 1, together with associated standard errors, for input into assessments of the resource. The results also caution against the danger of scientists reading more information into data than is really there. Keywords: anchovy, effective sample size, length distribution, ...

  6. prevalence and age distribution of peripheral hamartomas in adult ...

    African Journals Online (AJOL)

    1990-07-24

    Jul 24, 1990 ... However, the majority of deaths occurred in" the sixth decade in the autopsy population and in the seventh in the general population. The age distribution in black autopsy cases was, however, very different from that of blacks in the general population (Fig. 1). The cases of peripheral pulmonary hamartomas ...

  7. Bimodal and Gaussian Ising spin glasses in dimension two

    Science.gov (United States)

    Lundow, P. H.; Campbell, I. A.

    2016-02-01

    An analysis is given of numerical simulation data to size L =128 on the archetype square lattice Ising spin glasses (ISGs) with bimodal (±J ) and Gaussian interaction distributions. It is well established that the ordering temperature of both models is zero. The Gaussian model has a nondegenerate ground state and thus a critical exponent η ≡0 , and a continuous distribution of energy levels. For the bimodal model, above a size-dependent crossover temperature T*(L ) there is a regime of effectively continuous energy levels; below T*(L ) there is a distinct regime dominated by the highly degenerate ground state plus an energy gap to the excited states. T*(L ) tends to zero at very large L , leaving only the effectively continuous regime in the thermodynamic limit. The simulation data on both models are analyzed with the conventional scaling variable t =T and with a scaling variable τb=T2/(1 +T2) suitable for zero-temperature transition ISGs, together with appropriate scaling expressions. The data for the temperature dependence of the reduced susceptibility χ (τb,L ) and second moment correlation length ξ (τb,L ) in the thermodynamic limit regime are extrapolated to the τb=0 critical limit. The Gaussian critical exponent estimates from the simulations, η =0 and ν =3.55 (5 ) , are in full agreement with the well-established values in the literature. The bimodal critical exponents, estimated from the thermodynamic limit regime analyses using the same extrapolation protocols as for the Gaussian model, are η =0.20 (2 ) and ν =4.8 (3 ) , distinctly different from the Gaussian critical exponents.

  8. Refining Bimodal Microstructure of Materials with MSTRUCT

    Czech Academy of Sciences Publication Activity Database

    Matěj, Z.; Kadlecová, A.; Janeček, M.; Matějová, Lenka; Dopita, M.; Kužel, R.

    2014-01-01

    Roč. 29, S2 (2014), S35-S41 ISSN 0885-7156 R&D Projects: GA ČR GA14-23274S Grant - others:UK(CZ) UNCE 204023/2012 Institutional support: RVO:67985858 Keywords : XRD * bimodal * crystallite size Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.636, year: 2014

  9. Deaf Children's Bimodal Bilingualism and Education

    Science.gov (United States)

    Swanwick, Ruth

    2016-01-01

    This paper provides an overview of the research into deaf children's bilingualism and bilingual education through a synthesis of studies published over the last 15 years. This review brings together the linguistic and pedagogical work on bimodal bilingualism to inform educational practice. The first section of the review provides a synthesis of…

  10. Nonlinear dynamics of the bimodal optical computer

    Science.gov (United States)

    Caulfield, H. John

    1999-03-01

    In the bimodal optical computer, linear and nonlinear acts occur in rapid succession generating solutions to Ax equals b. Both chaos and stochastic resonance can appear in some cases. This is the first observation of such complexity effects in optical processors.

  11. Modeling the brain morphology distribution in the general aging population

    Science.gov (United States)

    Huizinga, W.; Poot, D. H. J.; Roshchupkin, G.; Bron, E. E.; Ikram, M. A.; Vernooij, M. W.; Rueckert, D.; Niessen, W. J.; Klein, S.

    2016-03-01

    Both normal aging and neurodegenerative diseases such as Alzheimer's disease cause morphological changes of the brain. To better distinguish between normal and abnormal cases, it is necessary to model changes in brain morphology owing to normal aging. To this end, we developed a method for analyzing and visualizing these changes for the entire brain morphology distribution in the general aging population. The method is applied to 1000 subjects from a large population imaging study in the elderly, from which 900 were used to train the model and 100 were used for testing. The results of the 100 test subjects show that the model generalizes to subjects outside the model population. Smooth percentile curves showing the brain morphology changes as a function of age and spatiotemporal atlases derived from the model population are publicly available via an interactive web application at agingbrain.bigr.nl.

  12. [Age distribution of transepithelial water loss in human nasal mucosa].

    Science.gov (United States)

    Miwa, Masato; Nakajima, Noriyuki; Hirose, Takashi; Iwasaki, Yoko; Murakami, Atsushi; Matsunaga, Mayumi; Watanabe, Kensuke

    2006-10-01

    Dry nose is a common complaint in the elderly. Age distribution of transepithelial water loss of human nasal mucosa (TEWL) value was evaluated in this study. Eighty-eight volunteers (50 men and 30 women) ranging from 10 to 75 years old were recruited for this study. Measurement of TEWL was performed on the inferior nasal turbinate. TEWL was measured with an evaporation meter applying Fick's law (Tewameter TM 300; Courage and Khazaka, Cologne, Germany). TEWL value tends to increase in order of age, indicating that the barrier function of epithelium may decline with age. The measurement of transepithelial water loss should be contributed to assess the efficiency of nasal mucosal barrier disorders in the elderly.

  13. Hematopoiesis and aging. IV. Mass and distribution of erythroid marrow in aged mice

    International Nuclear Information System (INIS)

    Boggs, D.R.

    1985-01-01

    Aged mice are ''anemic,'' i.e., they have a lower hematocrit than young adult mice, but this appears to be a ''dilutional'' anemia; the red cell mass is normal. Other observations have supported the hypothesis that basal erythropoiesis does not change as mice grow old. In the present study, the percentage of injected 59 Fe found in the skeleton and spleen, 59 Fe distribution between various bones and bone groups, and the number of nucleated erythroid cells per humerus were studied and the total mass of erythroid precursors was calculated. There was no significant difference in any of these values between mice aged 3-27 months. The variability of 59 Fe distribution within various skeletal parts was no greater in aged than in young mice. Thus, these data further strengthen the case for normal basal rates of erythropoiesis in aged mice

  14. Age related distributive justice and claims on resources.

    Science.gov (United States)

    Irwin, S

    1996-03-01

    The ageing population structure, and claims on resources by non-working groups, are seen by many to be contributing to a growing welfare crisis. In their arguments, relations between age groups and generations will become increasingly fraught, and welfare arrangements will be undermined, as 'unacceptable' levels of taxation blight the experience of a contracting workforce, required to resource a growing welfare population. However, more seems to be known about researchers' views on distributive justice than is known about the perceptions of their subject populations. It has not been demonstrated that members of age groups share interests which are consonant with their cohort experience, or perceive their interests to be in conflict with those members of other age groups or generations. This paper analyses empirical evidence on people's perceptions of who should get, and do, what, in developing an argument that standard processes do not place age groups or generations in antagonistic relationship. Understanding the relations between age groups and generations is essential to explaining change in patterns of inequality, but the interdependence of these relations suggest that they are part of a coherent social structure, and not likely to give rise to crisis in the ways predicted.

  15. Merging history of three bimodal clusters

    Science.gov (United States)

    Maurogordato, S.; Sauvageot, J. L.; Bourdin, H.; Cappi, A.; Benoist, C.; Ferrari, C.; Mars, G.; Houairi, K.

    2011-01-01

    We present a combined X-ray and optical analysis of three bimodal galaxy clusters selected as merging candidates at z ~ 0.1. These targets are part of MUSIC (MUlti-Wavelength Sample of Interacting Clusters), which is a general project designed to study the physics of merging clusters by means of multi-wavelength observations. Observations include spectro-imaging with XMM-Newton EPIC camera, multi-object spectroscopy (260 new redshifts), and wide-field imaging at the ESO 3.6 m and 2.2 m telescopes. We build a global picture of these clusters using X-ray luminosity and temperature maps together with galaxy density and velocity distributions. Idealized numerical simulations were used to constrain the merging scenario for each system. We show that A2933 is very likely an equal-mass advanced pre-merger ~200 Myr before the core collapse, while A2440 and A2384 are post-merger systems (~450 Myr and ~1.5 Gyr after core collapse, respectively). In the case of A2384, we detect a spectacular filament of galaxies and gas spreading over more than 1 h-1 Mpc, which we infer to have been stripped during the previous collision. The analysis of the MUSIC sample allows us to outline some general properties of merging clusters: a strong luminosity segregation of galaxies in recent post-mergers; the existence of preferential axes - corresponding to the merging directions - along which the BCGs and structures on various scales are aligned; the concomitance, in most major merger cases, of secondary merging or accretion events, with groups infalling onto the main cluster, and in some cases the evidence of previous merging episodes in one of the main components. These results are in good agreement with the hierarchical scenario of structure formation, in which clusters are expected to form by successive merging events, and matter is accreted along large-scale filaments. Based on data obtained with the European Southern Observatory, Chile (programs 072.A-0595, 075.A-0264, and 079.A-0425

  16. Phenotypic Diversity Using Bimodal and Unimodal Expression of Stress Response Proteins.

    Science.gov (United States)

    Garcia-Bernardo, Javier; Dunlop, Mary J

    2016-05-24

    Populations of cells need to express proteins to survive the sudden appearance of stressors. However, these mechanisms may be taxing. Populations can introduce diversity, allowing individual cells to stochastically switch between fast-growing and stress-tolerant states. One way to achieve this is to use genetic networks coupled with noise to generate bimodal distributions with two distinct subpopulations, each adapted to a stress condition. Another survival strategy is to rely on random fluctuations in gene expression to produce continuous, unimodal distributions of the stress response protein. To quantify the environmental conditions where bimodal versus unimodal expression is beneficial, we used a differential evolution algorithm to evolve optimal distributions of stress response proteins given environments with sudden fluctuations between low and high stress. We found that bimodality evolved for a large range of environmental conditions. However, we asked whether these findings were an artifact of considering two well-defined stress environments (low and high stress). As noise in the environment increases, or when there is an intermediate environment (medium stress), the benefits of bimodality decrease. Our results indicate that under realistic conditions, a continuum of resistance phenotypes generated through a unimodal distribution is sufficient to ensure survival without a high cost to the population. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  17. The Efficiency of the Bimodal System Transportation

    Directory of Open Access Journals (Sweden)

    Nada Štrumberger

    2012-10-01

    Full Text Available The development of fast railway results in an increased applicationof Trailer Train bimodal system transportation. Thetraffic costs are multiply reduced, particularly the variablecosts. On the other hand the environmental pollution from exhaustgases is also reduced. Therefore, by the year 2010 cargotransport should be preponderant~v used which would be characterisedby fast electric trains producing less noise, at lowercosts and with clean environment.

  18. The gender difference in the brain FDG distribution with aging

    International Nuclear Information System (INIS)

    Nakabeppu, Yoshiaki; Tanabe, Hiroaki; Jinguji, Megumi; Umanodan, Tomokazu; Nakajo, Masayuki; Nakajo, M.; Tateno, T.; Jinnouchi, S.

    2007-01-01

    The purpose of this study is to examine the change in brain fluorodeoxyglucose (FDG) distribution with aging. Subjects were 85 men and 116 women who had no mental abnormality and no evidence of cancer in the whole body FDG-positron emission tomography (PET) study for cancer checkup. The brain data were extracted from whole body data, and stratified according to the age: 30-39 (M: 10, F: 18), 40-49 (M: 11, F: 14), 50-59 (M: 10, F: 27), 60-64 (M: 11, F: 13), 65-69 (M: 11, F: 11), 70-74 (M: 11, F: 10), 75-79 (M: 13, F: 11), over 80 (M: 8, F: 12) years. Forties or more male and female stratified age groups were compared with each gender 30's age data using Statistical Parametric Mapping (SPM)2. In the man, the FDG activity of the bilateral temporal and frontal lobes decreased and the decreased domains were expanded with aging. But in the females, the decreased domains were complicated in 40-69 years old. Dynamic changes of sex hormones in the individual female menopause may affect the complicated results in the females. Further studies are needed to confirm it. (author)

  19. Early Bimodal Stimulation Benefits Language Acquisition for Children With Cochlear Implants.

    Science.gov (United States)

    Moberly, Aaron C; Lowenstein, Joanna H; Nittrouer, Susan

    2016-01-01

    Adding a low-frequency acoustic signal to the cochlear implant (CI) signal (i.e., bimodal stimulation) for a period of time early in life improves language acquisition. Children must acquire sensitivity to the phonemic units of language to develop most language-related skills, including expressive vocabulary, working memory, and reading. Acquiring sensitivity to phonemic structure depends largely on having refined spectral (frequency) representations available in the signal, which does not happen with CIs alone. Combining the low-frequency acoustic signal available through hearing aids with the CI signal can enhance signal quality. A period with this bimodal stimulation has been shown to improve language skills in very young children. This study examined whether these benefits persist into childhood. Data were examined for 48 children with CIs implanted under age 3 years, participating in a longitudinal study. All children wore hearing aids before receiving a CI, but upon receiving a first CI, 24 children had at least 1 year of bimodal stimulation (Bimodal group), and 24 children had only electric stimulation subsequent to implantation (CI-only group). Measures of phonemic awareness were obtained at second and fourth grades, along with measures of expressive vocabulary, working memory, and reading. Children in the Bimodal group generally performed better on measures of phonemic awareness, and that advantage was reflected in other language measures. Having even a brief period of time early in life with combined electric-acoustic input provides benefits to language learning into childhood, likely because of the enhancement in spectral representations provided.

  20. Bimodal nature in low-energy fission of light actinides

    International Nuclear Information System (INIS)

    Nagame, Yuichiro; Nishinaka, Ichiro; Tsukada, Kazuaki; Ikezoe, Hiroshi; Otsuki, Tsutomu; Sueki, Keisuke; Nakahara, Hiromichi; Kudo, Hisaaki.

    1995-01-01

    To solve various problems in the mass division process of light actinoids, some experiments on the basis of bimodal fission were carried. Mass and kinetic energy distribution of Th-232 and U-238 were determined. Pa-225 (N= 134) and Pa-227 (N=136), fission nuclei, were produced by Bi-209 + 0-16 and Bi-209 + 0-18 heavy ion nucleus reactions, and the mass yield distribution were determined by the time-of-flight method and the radiochemical procedure. From the results, two independent deforming processes were proved in the fission process of light actinoid nuclei. On the deforming process through the low fission barrier, nucleus fissioned after small deformation under the influence of stabilization of the shell structure of fission product. In the case of process through the high barrier, however, the nucleus fissioned after large deformation. The unsymmetrical mass division was derived from the former and the symmetrical one from the latter. (S.Y.)

  1. Movement, drivers and bimodality of the South Asian High

    Directory of Open Access Journals (Sweden)

    M. Nützel

    2016-11-01

    Full Text Available The South Asian High (SAH is an important component of the summer monsoon system in Asia. In this study we investigate the location and drivers of the SAH at 100 hPa during the boreal summers of 1979 to 2014 on interannual, seasonal and synoptic timescales using seven reanalyses and observational data. Our comparison of the different reanalyses focuses especially on the bimodality of the SAH, i.e. the two preferred modes of the SAH centre location: the Iranian Plateau to the west and the Tibetan Plateau to the east. We find that only the National Centers for Environmental Prediction–National Center of Atmospheric Research (NCEP–NCAR reanalysis shows a clear bimodal structure of the SAH centre distribution with respect to daily and pentad (5 day mean data. Furthermore, the distribution of the SAH centre location is highly variable from year to year. As in simple model studies, which connect the SAH to heating in the tropics, we find that the mean seasonal cycle of the SAH and its centre are dominated by the expansion of convection in the South Asian region (70–130° E  ×  15–30° N on the south-eastern border of the SAH. A composite analysis of precipitation and outgoing long-wave radiation data with respect to the location of the SAH centre reveals that a more westward (eastward location of the SAH is related to stronger (weaker convection and rainfall over India and weaker (stronger precipitation over the western Pacific.

  2. Refractive errors in a Brazilian population: age and sex distribution.

    Science.gov (United States)

    Ferraz, Fabio H; Corrente, José E; Opromolla, Paula; Padovani, Carlos Roberto; Schellini, Silvana A

    2015-01-01

    To determine the prevalence of refractive errors and their distribution according to age and sex in a Brazilian population. This population-based cross-sectional study involved 7654 Brazilian inhabitants of nine municipalities of Sao Paulo State, Brazil, between March 2004 and July 2005. Participants aged >1 year were selected using a random, stratified, household cluster sampling technique, excluding individuals with previous refractive or cataract surgery. Myopia was defined as spherical equivalent (SE) ≤-0.5D, high myopia as SE ≤-3.0D, hyperopia as SE ≥+0.5D, high hyperopia as SE ≥+3D, astigmatism as ≤-0.5DC and anisometropia as ≥1.0D difference between eyes. Age, sex, complaints and a comprehensive eye examination including cycloplegic refraction test were collected and analysed using descriptive analysis, univariate and multivariate methods. The prevalence of astigmatism was 59.7%, hyperopia 33.8% and myopia was 25.3%. Astigmatism had a progressive increase with age. With-the-rule (WTR) axes of astigmatism were more frequently observed in the young participants and the against-the-rule (ATR) axes were more frequent in the older subjects. The onset of myopia occurred more frequently between the 2nd and 3rd decades of life. Anisometropia showed a prevalence of 13.2% (95% CI 12.4-13.9; p refractive error and hyperopia was also associated with sex. Hyperopia was associated with WTR axes (odds ratio 0.73; 95% CI: 0.6-0.8; p prevalent refractive error in a Brazilian population. There was a strong relationship between age and all refractive errors and between hyperopia and sex. WTR astigmatism was more frequently associated with hyperopia and ATR astigmatism with myopia. The vast majority of participants had low-grade refractive error, which favours planning aimed at correction of refractive error in the population. © 2014 The Authors Ophthalmic & Physiological Optics © 2014 The College of Optometrists.

  3. Age distributions of Greenlandic dwarf shrubs support concept of negligible actuarial senescence

    DEFF Research Database (Denmark)

    Dahlgren, Johan; Rizzi, Silvia; Schweingruber, Fritz

    2016-01-01

    are independent of age. Actuarial senescence is thus negligible in these dwarf shrub populations. We suggest that smoothing techniques such as pclm enable consideration of noisy age data for determining age distributions. These distributions may, in turn, reveal age effects on demographic rates. Moreover, age...

  4. Penetration in bimodal, polydisperse granular material

    KAUST Repository

    Kouraytem, N.

    2016-11-07

    We investigate the impact penetration of spheres into granular media which are compositions of two discrete size ranges, thus creating a polydisperse bimodal material. We examine the penetration depth as a function of the composition (volume fractions of the respective sizes) and impact speed. Penetration depths were found to vary between delta = 0.5D(0) and delta = 7D(0), which, for mono-modal media only, could be correlated in terms of the total drop height, H = h + delta, as in previous studies, by incorporating correction factors for the packing fraction. Bimodal data can only be collapsed by deriving a critical packing fraction for each mass fraction. The data for the mixed grains exhibit a surprising lubricating effect, which was most significant when the finest grains [d(s) similar to O(30) mu m] were added to the larger particles [d(l) similar to O(200 - 500) mu m], with a size ratio, epsilon = d(l)/d(s), larger than 3 and mass fractions over 25%, despite the increased packing fraction. We postulate that the small grains get between the large grains and reduce their intergrain friction, only when their mass fraction is sufficiently large to prevent them from simply rattling in the voids between the large particles. This is supported by our experimental observations of the largest lubrication effect produced by adding small glass beads to a bed of large sand particles with rough surfaces.

  5. Martian channels and valleys - Their characteristics, distribution, and age

    Science.gov (United States)

    Carr, M. H.; Clow, G. D.

    1981-01-01

    The distribution and ages of Martian channels and valleys, which are generally believed to have been cut by running water, are examined with particular emphasis on the small branching networks referred to as runoff channels or valley networks. Valleys at latitudes from 65 deg S to 65 deg N were surveyed on Viking images at resolutions between 125 and 300 m. Almost all of the valleys are found in the old cratered terrain, in areas characterized by high elevations, low albedos and low violet/red ratios. The networks are deduced to have formed early in the history of the planet, with a formation rate declining rapidly shortly after the decline of the cratering rate 3.9 billion years ago. Two types of outflow channels are distinguished: unconfined, in which broad swaths of terrain are scoured, and confined, in which flow is restricted to discrete channels. Both types start at local sources, and have formed episodically throughout Martian history. Fretted channels, found mainly in two latitude belts characterized by relatively rapid erosion along escarpments, are explained by the lateral enlargement of other channels by mass wasting.

  6. Speech Recognition and Cognitive Skills in Bimodal Cochlear Implant Users

    Science.gov (United States)

    Hua, Håkan; Johansson, Björn; Magnusson, Lennart; Lyxell, Björn; Ellis, Rachel J.

    2017-01-01

    Purpose: To examine the relation between speech recognition and cognitive skills in bimodal cochlear implant (CI) and hearing aid users. Method: Seventeen bimodal CI users (28-74 years) were recruited to the study. Speech recognition tests were carried out in quiet and in noise. The cognitive tests employed included the Reading Span Test and the…

  7. Bimodal condensation silicone elastomers as dielectric elastomers

    DEFF Research Database (Denmark)

    Yu, Liyun; Madsen, Frederikke Bahrt; Skov, Anne Ladegaard

    as well as high electrical and mechanical breakdown strengths. [1] Most model elastomers are prepared by an end-linking process using a crosslinker with a certain functionality ƒ and a linear polymer with functional groups in both ends, and the resulting networks are so-called unimodal networks where...... unimodal refers to that there is one polymer only in the system. As an alternative to unimodal networks there are the bimodal networks where two polymers with significantly different molecular weights are mixed with one crosslinker. [2]Silicone rubber can be divided into condensation type and addition type...... elastomers were prepared by mixing different mass ratios (9:1, 8:2, 7:3, 6:4, 5:5, 4:6) between long polydimethylsiloxane (PDMS) chains and short PDMS chains. The resulting elastomers were investigated with respect to their rheology, dielectric properties, tensile strength, electrical breakdown, as well...

  8. Spectra of globular clusters in the Sombrero galaxy: evidence for spectroscopic metallicity bimodality

    Science.gov (United States)

    Alves-Brito, Alan; Hau, George K. T.; Forbes, Duncan A.; Spitler, Lee R.; Strader, Jay; Brodie, Jean P.; Rhode, Katherine L.

    2011-11-01

    We present a large sample of over 200 integrated-light spectra of confirmed globular clusters (GCs) associated with the Sombrero (M104) galaxy taken with the Deep Imaging Multi-Object Spectrograph (DEIMOS) instrument on the Keck telescope. A significant fraction of the spectra have signal-to-noise ratio levels high enough to allow measurements of GC metallicities using the method of Brodie & Huchra. We find a distribution of spectroscopic metallicities in the range -2.2 < [Fe/H] < +0.1 that is bimodal, with peaks at [Fe/H]˜-1.4 and -0.6. Thus, the GC system of the Sombrero galaxy, like a few other galaxies now studied in detail, reveals a bimodal spectroscopic metallicity distribution supporting the long-held belief that colour bimodality reflects two metallicity subpopulations. This further suggests that the transformation from optical colour to metallicity for old stellar populations, such as GCs, is not strongly non-linear. We also explore the radial and magnitude distribution with metallicity for GC subpopulations but small number statistics prevent any clear trends in these distributions. Based on observations obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration.

  9. Phenotypic Diversity Using Bimodal and Unimodal Expression of Stress Response Proteins

    OpenAIRE

    Garcia-Bernardo, Javier; Dunlop, Mary J.

    2016-01-01

    Populations of cells need to express proteins to survive the sudden appearance of stressors. However, these mechanisms may be taxing. Populations can introduce diversity, allowing individual cells to stochastically switch between fast-growing and stress-tolerant states. One way to achieve this is to use genetic networks coupled with noise to generate bimodal distributions with two distinct subpopulations, each adapted to a stress condition. Another survival strategy is to rely on random fluct...

  10. Velocity selection for ultra-cold atoms using bimodal mazer cavity

    International Nuclear Information System (INIS)

    Irshad, A.; Qamar, S.

    2009-04-01

    In this paper, we discuss the velocity selection of ultra-cold three-level atoms in Λ configuration using a micromazer. Our model is the same as discussed by Arun et al., for mazer action in a bimodal cavity. We have shown that significantly narrowed velocity distribution of ultra-cold atoms can be obtained in this system due to the presence of dark states. (author)

  11. Paleodemographic age-at-death distributions of two Mexican skeletal collections: a comparison of transition analysis and traditional aging methods.

    Science.gov (United States)

    Bullock, Meggan; Márquez, Lourdes; Hernández, Patricia; Ruíz, Fernando

    2013-09-01

    Traditional methods of aging adult skeletons suffer from the problem of age mimicry of the reference collection, as described by Bocquet-Appel and Masset (1982). Transition analysis (Boldsen et al., 2002) is a method of aging adult skeletons that addresses the problem of age mimicry of the reference collection by allowing users to select an appropriate prior probability. In order to evaluate whether transition analysis results in significantly different age estimates for adults, the method was applied to skeletal collections from Postclassic Cholula and Contact-Period Xochimilco. The resulting age-at-death distributions were then compared with age-at-death distributions for the two populations constructed using traditional aging methods. Although the traditional aging methods result in age-at-death distributions with high young adult mortality and few individuals living past the age of 50, the age-at-death distributions constructed using transition analysis indicate that most individuals who lived into adulthood lived past the age of 50. Copyright © 2013 Wiley Periodicals, Inc.

  12. Age-related Differences in the Clinical Presentation, Associated Metabolic Abnormality, and Estimated Cardiovascular Risks from Nonalcoholic Fatty Liver Disease: A Cross-sectional Study from Health Evaluation Center in Taiwan

    Directory of Open Access Journals (Sweden)

    Chuan-Chuan Liu

    2010-12-01

    Conclusion: The prevalence of NAFLD demonstrated a bimodal distribution with age in different genders. Although baseline characters and biochemical markers were demonstrated to be potential screening tools in detecting such clinical abnormality, they actually exerted diverse capabilities in the prediction of NAFLD in the different age groups. Traditional cardiovascular risk scores were less effective in predicting NAFLD in the aging group population.

  13. Gaze distribution analysis and saliency prediction across age groups.

    Science.gov (United States)

    Krishna, Onkar; Helo, Andrea; Rämä, Pia; Aizawa, Kiyoharu

    2018-01-01

    Knowledge of the human visual system helps to develop better computational models of visual attention. State-of-the-art models have been developed to mimic the visual attention system of young adults that, however, largely ignore the variations that occur with age. In this paper, we investigated how visual scene processing changes with age and we propose an age-adapted framework that helps to develop a computational model that can predict saliency across different age groups. Our analysis uncovers how the explorativeness of an observer varies with age, how well saliency maps of an age group agree with fixation points of observers from the same or different age groups, and how age influences the center bias tendency. We analyzed the eye movement behavior of 82 observers belonging to four age groups while they explored visual scenes. Explorative- ness was quantified in terms of the entropy of a saliency map, and area under the curve (AUC) metrics was used to quantify the agreement analysis and the center bias tendency. Analysis results were used to develop age adapted saliency models. Our results suggest that the proposed age-adapted saliency model outperforms existing saliency models in predicting the regions of interest across age groups.

  14. Estimating the formation age distribution of continental crust by unmixing zircon ages

    Science.gov (United States)

    Korenaga, Jun

    2018-01-01

    Continental crust provides first-order control on Earth's surface environment, enabling the presence of stable dry landmasses surrounded by deep oceans. The evolution of continental crust is important for atmospheric evolution, because continental crust is an essential component of deep carbon cycle and is likely to have played a critical role in the oxygenation of the atmosphere. Geochemical information stored in the mineral zircon, known for its resilience to diagenesis and metamorphism, has been central to ongoing debates on the genesis and evolution of continental crust. However, correction for crustal reworking, which is the most critical step when estimating original formation ages, has been incorrectly formulated, undermining the significance of previous estimates. Here I suggest a simple yet promising approach for reworking correction using the global compilation of zircon data. The present-day distribution of crustal formation age estimated by the new "unmixing" method serves as the lower bound to the true crustal growth, and large deviations from growth models based on mantle depletion imply the important role of crustal recycling through the Earth history.

  15. Mean age distribution of inorganic soil-nitrogen

    Science.gov (United States)

    Woo, Dong K.; Kumar, Praveen

    2016-07-01

    Excess reactive nitrogen in soils of intensively managed landscapes causes adverse environmental impact, and continues to remain a global concern. Many novel strategies have been developed to provide better management practices and, yet, the problem remains unresolved. The objective of this study is to develop a model to characterize the "age" of inorganic soil-nitrogen (nitrate, and ammonia/ammonium). We use the general theory of age, which provides an assessment of the time elapsed since inorganic nitrogen has been introduced into the soil system. We analyze a corn-corn-soybean rotation, common in the Midwest United States, as an example application. We observe two counter-intuitive results: (1) the mean nitrogen age in the topsoil layer is relatively high; and (2) mean nitrogen age is lower under soybean cultivation compared to corn although no fertilizer is applied for soybean cultivation. The first result can be explained by cation-exchange of ammonium that retards the leaching of nitrogen, resulting in an increase in the mean nitrogen age near the soil surface. The second result arises because the soybean utilizes the nitrogen fertilizer left from the previous year, thereby removing the older nitrogen and reducing mean nitrogen age. Estimating the mean nitrogen age can thus serve as an important tool to disentangle complex nitrogen dynamics by providing a nuanced characterization of the time scales of soil-nitrogen transformation and transport processes.

  16. Functionalized bimodal mesoporous silicas as carriers for controlled aspirin delivery

    Science.gov (United States)

    Gao, Lin; Sun, Jihong; Li, Yuzhen

    2011-08-01

    The bimodal mesoporous silica modified with 3-aminopropyltriethoxysilane was performed as the aspirin carrier. The samples' structure, drug loading and release profiles were characterized with X-ray diffraction, scanning electron microscopy, N 2 adsorption and desorption, Fourier transform infrared spectroscopy, TG analysis, elemental analysis and UV-spectrophotometer. For further exploring the effects of the bimodal mesopores on the drug delivery behavior, the unimodal mesoporous material MCM-41 was also modified as the aspirin carrier. Meantime, Korsmeyer-Peppas equation ft= ktn was employed to analyze the dissolution data in details. It is indicated that the bimodal mesopores are beneficial for unrestricted drug molecules diffusing and therefore lead to a higher loading and faster releasing than that of MCM-41. The results show that the aspirin delivery properties are influenced considerably by the mesoporous matrix, whereas the large pore of bimodal mesoporous silica is the key point for the improved controlled-release properties.

  17. Distribution of Young Forests and Estimated Stand Age across Russia, 2012

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides the distribution of young forests (forests less than 27 years of age) and their estimated stand ages across the full extent of Russia at 500-m...

  18. Bimodal distribution of fasting gastric acidity in a rural African ...

    African Journals Online (AJOL)

    Setting. The people of Transkei eat a diet high in linoleic acid, the principal fatty acid in maize. The theory has been put forward that a diet high in linoleic acid and low in fat and riboflavin, such as the traditional diet in Transkei, results in overproduction of prostaglandin E2 in the gastric mucosa, and that this overproduction ...

  19. ORIGINAL ARTICLES Bimodal distribution of fasting gastric acidity ...

    African Journals Online (AJOL)

    2003-10-18

    Oct 18, 2003 ... in riboflavin. It has been suggested' that these dietary elements promote high prostaglandin E2 (PGE2) production in the stomach; PGE2 suppresses gastric .... Table I. Frequency of sonsumption of individual food items and relation to pH. Odds ratio. Consumed. Consumed for pH > 4 (food. Item daily(%).

  20. Bimodal Programming: A Survey of Current Clinical Practice.

    Science.gov (United States)

    Siburt, Hannah W; Holmes, Alice E

    2015-06-01

    The purpose of this study was to determine the current clinical practice in approaches to bimodal programming in the United States. To be specific, if clinicians are recommending bimodal stimulation, who programs the hearing aid in the bimodal condition, and what method is used for programming the hearing aid? An 11-question online survey was created and sent via email to a comprehensive list of cochlear implant programming centers in the United States. The survey was sent to 360 recipients. Respondents in this study represented a diverse group of clinical settings (response rate: 26%). Results indicate little agreement about who programs the hearing aids, when they are programmed, and how they are programmed in the bimodal condition. Analysis of small versus large implant centers indicated small centers are less likely to add a device to the contralateral ear. Although a growing number of cochlear implant recipients choose to wear a hearing aid on the contralateral ear, there is inconsistency in the current clinical approach to bimodal programming. These survey results provide evidence of large variability in the current bimodal programming practices and indicate a need for more structured clinical recommendations and programming approaches.

  1. Parallel Distributed Processing Theory in the Age of Deep Networks.

    Science.gov (United States)

    Bowers, Jeffrey S

    2017-12-01

    Parallel distributed processing (PDP) models in psychology are the precursors of deep networks used in computer science. However, only PDP models are associated with two core psychological claims, namely that all knowledge is coded in a distributed format and cognition is mediated by non-symbolic computations. These claims have long been debated in cognitive science, and recent work with deep networks speaks to this debate. Specifically, single-unit recordings show that deep networks learn units that respond selectively to meaningful categories, and researchers are finding that deep networks need to be supplemented with symbolic systems to perform some tasks. Given the close links between PDP and deep networks, it is surprising that research with deep networks is challenging PDP theory. Copyright © 2017. Published by Elsevier Ltd.

  2. Age and sex distribution of blindness in Ahoada East Local ...

    African Journals Online (AJOL)

    Conclusion: This study found blindness to be commoner in the older age groups, and the male gender appeared to be an important risk factor. Eye health education must target such vulnerable groups. Males especially should be enlightened on social habits and environmental factors that increase their risk. Keywords: ...

  3. Relationship of intratumoural protein expression patterns to age and Epstein-Barr virus status in classical Hodgkin lymphoma

    DEFF Research Database (Denmark)

    Ludvigsen, Maja; Kamper, Peter; Hamilton-Dutroit, Stephen J

    2015-01-01

    In Western countries, the age distribution of Hodgkin lymphoma (HL) follows a characteristic bimodal curve showing an early and a late peak at approximately 35 and 70 yr, respectively. Furthermore, the presence of latent Epstein-Barr virus (EBV) genome in the Hodgkin Reed-Sternberg cells...

  4. Age distribution of abnormal pap smear in a secondary hospital in ...

    African Journals Online (AJOL)

    Age distribution of abnormal pap smear in a secondary hospital in south-west Nigeria. ... Objective: To determine the age distribution pattern of abnormal Paps smear in women in our environment in order to have a basis for the points of entry and exit for cervical cancer screening protocol. Materials and Method: In this ...

  5. Electrical power transmission and distribution aging and life extension techniques

    CERN Document Server

    Chudnovsky, Bella H

    2012-01-01

    ""The focus of this unique reference book is four critical areas in the manufacturing of power distribution components. These areas are plating, lubrication, insulator failure, and maintenance. ... The many SEM images, x-ray studies, photos, and tabular data make for a very convenient reference source for diagnosing plating problems. ... Examples often help to drive home a point, and many case studies illustrating the various failure modes described throughout the book are included. These could prove to be an invaluable source of information when trying to diagnose unknown field failures. ...

  6. Strategic Decision-Making Learning from Label Distributions: An Approach for Facial Age Estimation.

    Science.gov (United States)

    Zhao, Wei; Wang, Han

    2016-06-28

    Nowadays, label distribution learning is among the state-of-the-art methodologies in facial age estimation. It takes the age of each facial image instance as a label distribution with a series of age labels rather than the single chronological age label that is commonly used. However, this methodology is deficient in its simple decision-making criterion: the final predicted age is only selected at the one with maximum description degree. In many cases, different age labels may have very similar description degrees. Consequently, blindly deciding the estimated age by virtue of the highest description degree would miss or neglect other valuable age labels that may contribute a lot to the final predicted age. In this paper, we propose a strategic decision-making label distribution learning algorithm (SDM-LDL) with a series of strategies specialized for different types of age label distribution. Experimental results from the most popular aging face database, FG-NET, show the superiority and validity of all the proposed strategic decision-making learning algorithms over the existing label distribution learning and other single-label learning algorithms for facial age estimation. The inner properties of SDM-LDL are further explored with more advantages.

  7. Analyses of length and age distributions using continuation-ratio logits

    DEFF Research Database (Denmark)

    Rindorf, Anna; Lewy, Peter

    2001-01-01

    allows statistical testing of the effects of both continuous and discrete variables. Further, by utilising the smoothness of length and age distributions as a function of length, the method provides more accurate estimates of these distributions than traditional methods. The observations are assumed...... to be multinomially distributed, but cases in which the variance exceeds that of this distribution may also be analysed. The implementation of the method in existing statistical analysis software is straightforward and is demonstrated using length and age distributions of the lesser sandeel, Ammodytes marinus Raitt...

  8. Localization ability with bimodal hearing aids and bilateral cochlear implants

    Science.gov (United States)

    Seeber, Bernhard U.; Baumann, Uwe; Fastl, Hugo

    2004-09-01

    After successful cochlear implantation in one ear, some patients continue to use a hearing aid at the contralateral ear. They report an improved reception of speech, especially in noise, as well as a better perception of music when the hearing aid and cochlear implant are used in this bimodal combination. Some individuals in this bimodal patient group also report the impression of an improved localization ability. Similar experiences are reported by the group of bilateral cochlear implantees. In this study, a survey of 11 bimodally and 4 bilaterally equipped cochlear implant users was carried out to assess localization ability. Individuals in the bimodal implant group were all provided with the same type of hearing aid in the opposite ear, and subjects in the bilateral implant group used cochlear implants of the same manufacturer on each ear. Subjects adjusted the spot of a computer-controlled laser-pointer to the perceived direction of sound incidence in the frontal horizontal plane by rotating a trackball. Two subjects of the bimodal group who had substantial residual hearing showed localization ability in the bimodal configuration, whereas using each single device only the subject with better residual hearing was able to discriminate the side of sound origin. Five other subjects with more pronounced hearing loss displayed an ability for side discrimination through the use of bimodal aids, while four of them were already able to discriminate the side with a single device. Of the bilateral cochlear implant group one subject showed localization accuracy close to that of normal hearing subjects. This subject was also able to discriminate the side of sound origin using the first implanted device alone. The other three bilaterally equipped subjects showed limited localization ability using both devices. Among them one subject demonstrated a side-discrimination ability using only the first implanted device.

  9. Functionalized bimodal mesoporous silicas as carriers for controlled aspirin delivery

    International Nuclear Information System (INIS)

    Gao Lin; Sun Jihong; Li Yuzhen

    2011-01-01

    The bimodal mesoporous silica modified with 3-aminopropyltriethoxysilane was performed as the aspirin carrier. The samples' structure, drug loading and release profiles were characterized with X-ray diffraction, scanning electron microscopy, N 2 adsorption and desorption, Fourier transform infrared spectroscopy, TG analysis, elemental analysis and UV-spectrophotometer. For further exploring the effects of the bimodal mesopores on the drug delivery behavior, the unimodal mesoporous material MCM-41 was also modified as the aspirin carrier. Meantime, Korsmeyer-Peppas equation f t =kt n was employed to analyze the dissolution data in details. It is indicated that the bimodal mesopores are beneficial for unrestricted drug molecules diffusing and therefore lead to a higher loading and faster releasing than that of MCM-41. The results show that the aspirin delivery properties are influenced considerably by the mesoporous matrix, whereas the large pore of bimodal mesoporous silica is the key point for the improved controlled-release properties. - Graphical abstract: Loading (A) and release profiles (B) of aspirin in N-BMMs and N-MCM-41 indicated that BMMs have more drug loading capacity and faster release rate than that MCM-41. Highlights: → Bimodal mesoporous silicas (BMMs) and MCM-41 modified with amino group via post-treatment procedure. → Loading and release profiles of aspirin in modified BMMs and MCM-41. → Modified BMMs have more drug loading capacity and faster release rate than that modified MCM-41.

  10. Aggressive Bimodal Communication in Domestic Dogs, Canis familiaris.

    Science.gov (United States)

    Déaux, Éloïse C; Clarke, Jennifer A; Charrier, Isabelle

    2015-01-01

    Evidence of animal multimodal signalling is widespread and compelling. Dogs' aggressive vocalisations (growls and barks) have been extensively studied, but without any consideration of the simultaneously produced visual displays. In this study we aimed to categorize dogs' bimodal aggressive signals according to the redundant/non-redundant classification framework. We presented dogs with unimodal (audio or visual) or bimodal (audio-visual) stimuli and measured their gazing and motor behaviours. Responses did not qualitatively differ between the bimodal and two unimodal contexts, indicating that acoustic and visual signals provide redundant information. We could not further classify the signal as 'equivalent' or 'enhancing' as we found evidence for both subcategories. We discuss our findings in relation to the complex signal framework, and propose several hypotheses for this signal's function.

  11. Aggressive Bimodal Communication in Domestic Dogs, Canis familiaris.

    Directory of Open Access Journals (Sweden)

    Éloïse C Déaux

    Full Text Available Evidence of animal multimodal signalling is widespread and compelling. Dogs' aggressive vocalisations (growls and barks have been extensively studied, but without any consideration of the simultaneously produced visual displays. In this study we aimed to categorize dogs' bimodal aggressive signals according to the redundant/non-redundant classification framework. We presented dogs with unimodal (audio or visual or bimodal (audio-visual stimuli and measured their gazing and motor behaviours. Responses did not qualitatively differ between the bimodal and two unimodal contexts, indicating that acoustic and visual signals provide redundant information. We could not further classify the signal as 'equivalent' or 'enhancing' as we found evidence for both subcategories. We discuss our findings in relation to the complex signal framework, and propose several hypotheses for this signal's function.

  12. Visualisation and characterisation of heterogeneous bimodal PDMS networks

    DEFF Research Database (Denmark)

    Bahrt, Frederikke; Daugaard, Anders Egede; Fleury, Clemence

    2014-01-01

    The existence of short-chain domains in heterogeneous bimodal PDMS networks has been confirmed visually, for the first time, through confocal fluorescence microscopy. The networks were prepared using a controlled reaction scheme where short PDMS chains were reacted below the gelation point...... bimodal networks with short-chain domains within a long-chain network. The average sizes of the short-chain domains were found to vary from 2.1 to 5.7 mm depending on the short-chain content. The visualised network structure could be correlated thereafter to the elastic properties, which were determined...... by rheology. All heterogeneous bimodal networks displayed significantly lower moduli than mono-modal PDMS elastomers prepared from the long polymer chains. Low-loss moduli as well as low-sol fractions indicate that low-elastic moduli can be obtained without compromising the network's structure...

  13. Performance Comparisons of Nanoaluminum, Coated Microaluminum and Their Bimodal Mixtures

    Science.gov (United States)

    Woody, D. L.; Dokhan, A.; Johnson, C. E.

    2004-07-01

    Comparison studies of materials containing standard nano aluminum (ultrafine) and micro aluminum coated with BaSO4 were performed. Differential thermal analysis and thermogravimetric analysis output were used to observe the effect of adding an unconventional coating to micron-sized aluminum particle materials. These results were compared to those of ultrafine aluminum particles. Bimodal combinations of ultrafine aluminum and micron-sized aluminum (coated and uncoated) were observed also. These preliminary results showed an interaction between the ultrafine aluminum (UFAL) and micron-sized aluminum in bimodal mixtures.

  14. Aging transition in systems of oscillators with global distributed-delay coupling.

    Science.gov (United States)

    Rahman, B; Blyuss, K B; Kyrychko, Y N

    2017-09-01

    We consider a globally coupled network of active (oscillatory) and inactive (nonoscillatory) oscillators with distributed-delay coupling. Conditions for aging transition, associated with suppression of oscillations, are derived for uniform and gamma delay distributions in terms of coupling parameters and the proportion of inactive oscillators. The results suggest that for the uniform distribution increasing the width of distribution for the same mean delay allows aging transition to happen for a smaller coupling strength and a smaller proportion of inactive elements. For gamma distribution with sufficiently large mean time delay, it may be possible to achieve aging transition for an arbitrary proportion of inactive oscillators, as long as the coupling strength lies in a certain range.

  15. Quantitative analysis of cone photoreceptor distribution and its relationship with axial length, age, and early age-related macular degeneration.

    Directory of Open Access Journals (Sweden)

    Ryo Obata

    Full Text Available PURPOSE: It has not been clarified whether early age-related macular degeneration (AMD is associated with cone photoreceptor distribution. We used adaptive optics fundus camera to examine cone photoreceptors in the macular area of aged patients and quantitatively analyzed its relationship between the presence of early AMD and cone distribution. METHODS: Sixty cases aged 50 or older were studied. The eyes were examined with funduscopy and spectral-domain optical coherence tomography to exclude the eyes with any abnormalities at two sites of measurement, 2° superior and 5° temporal to the fovea. High-resolution retinal images with cone photoreceptor mosaic were obtained with adaptive optics fundus camera (rtx1, Imagine Eyes, France. After adjusting for axial length, cone packing density was calculated and the relationship with age, axial length, or severity of early AMD based on the age-related eye disease study (AREDS classification was analyzed. RESULTS: Patient's age ranged from 50 to 77, and axial length from 21.7 to 27.5 mm. Mean density in metric units and that in angular units were 24,900 cells/mm2, 2,170 cells/deg2 at 2° superior, and 18,500 cells/mm2, 1,570 cels/deg2 at 5° temporal, respectively. Axial length was significantly correlated with the density calculated in metric units, but not with that in angular units. Age was significantly correlated with the density both in metric and angular units at 2° superior. There was no significant difference in the density in metric and angular units between the eyes with AREDS category one and those with categories two or three. CONCLUSION: Axial length and age were significantly correlated with parafoveal cone photoreceptor distribution. The results do not support that early AMD might influence cone photoreceptor density in the area without drusen or pigment abnormalities.

  16. Estimating the Spatial Distribution of Groundwater Age Using Synoptic Surveys of Environmental Tracers in Streams

    Science.gov (United States)

    Gardner, W. P.

    2017-12-01

    A model which simulates tracer concentration in surface water as a function the age distribution of groundwater discharge is used to characterize groundwater flow systems at a variety of spatial scales. We develop the theory behind the model and demonstrate its application in several groundwater systems of local to regional scale. A 1-D stream transport model, which includes: advection, dispersion, gas exchange, first-order decay and groundwater inflow is coupled a lumped parameter model that calculates the concentration of environmental tracers in discharging groundwater as a function of the groundwater residence time distribution. The lumped parameters, which describe the residence time distribution, are allowed to vary spatially, and multiple environmental tracers can be simulated. This model allows us to calculate the longitudinal profile of tracer concentration in streams as a function of the spatially variable groundwater age distribution. By fitting model results to observations of stream chemistry and discharge, we can then estimate the spatial distribution of groundwater age. The volume of groundwater discharge to streams can be estimated using a subset of environmental tracers, applied tracers, synoptic stream gauging or other methods, and the age of groundwater then estimated using the previously calculated groundwater discharge and observed environmental tracer concentrations. Synoptic surveys of SF6, CFC's, 3H and 222Rn, along with measured stream discharge are used to estimate the groundwater inflow distribution and mean age for regional scale surveys of the Berland River in west-central Alberta. We find that groundwater entering the Berland has observable age, and that the age estimated using our stream survey is of similar order to limited samples from groundwater wells in the region. Our results show that the stream can be used as an easily accessible location to constrain the regional scale spatial distribution of groundwater age.

  17. Aspects of stochastic resonance in Josephson junction, bimodal ...

    Indian Academy of Sciences (India)

    the noise amplitude helps to define maximum SNR or peak SNR for an optimum amplitude of input noise. Although .... Here we consider a typical 2-parameter bimodal cubic map defined by. Xn+1 = b + aXn − X3 n. (2) ... due to shuttling with chaotic input of a logistic map (called chaotic resonance) have been reported earlier ...

  18. Interaural bimodal pitch matching with two-formant vowels

    DEFF Research Database (Denmark)

    Guérit, François; Chalupper, Josef; Santurette, Sébastien

    2013-01-01

    For bimodal patients, with a hearing aid (HA) in one ear and a cochlear implant (CI) in the opposite ear, usually a default frequency-to-electrode map is used in the CI. This assumes that the human brain can adapt to interaural place-pitch mismatches. This “one-size-fits-all” method might be part...

  19. Stochastic resonance and chaotic resonance in bimodal maps: A ...

    Indian Academy of Sciences (India)

    We present the results of an extensive numerical study on the phenomenon of stochastic resonance in a bimodal cubic map. Both Gaussian random noise as well as deterministic chaos are used as input to drive the system between the basins. Our main result is that when two identical systems capable of stochastic ...

  20. Effects of edge contrast on redback salamander distribution in even-aged northern hardwoods

    Science.gov (United States)

    Richard M. DeGraaf; Mariko. Yamasaki

    2002-01-01

    Terrestrial salamanders are sensitive to forest disturbance associated with even-aged management. We studied the distribution of redback salamanders (Plethodon cinereus) for 4 yr at edges between even-aged northern hardwood stands along three replicate transects in each of three edge contrast types: regeneration/mature, sapling/mature, and...

  1. Age distributions of Greenlandic dwarf shrubs support concept of negligible actuarial senescence

    Czech Academy of Sciences Publication Activity Database

    Dahlgren, J. P.; Rizzi, S.; Schweingruber, F. H.; Hellmann, L.; Büntgen, Ulf

    2016-01-01

    Roč. 7, č. 10 (2016), č. článku e01521. ISSN 2150-8925 R&D Projects: GA MŠk(CZ) EE2.3.20.0248 Institutional support: RVO:67179843 Keywords : actuarial senescence * age distribution * age structure * Arctic dwarf shrubs * dendroecology * individual survival * mortality * penalized composite link model * plant aging * shrub demography Subject RIV: EH - Ecology, Behaviour Impact factor: 2.490, year: 2016

  2. A theory of the cancer age-specific incidence data based on extreme value distributions

    Directory of Open Access Journals (Sweden)

    Luis Soto-Ortiz

    2012-03-01

    Full Text Available The incidence of cancers varies with age, if normalized this is called the age-specific incidence. A mathematical model that describes this variation should provide a better understanding of how cancers develop. We suggest that the age-specific incidence should follow an extreme value distribution, based on three widely accepted assumptions: (1 a tumor develops from a single cell, (2 many potential tumor progenitor cells exist in a tissue, and (3 cancer is diagnosed when the first of these many potential tumor cells develops into a tumor. We tested this by comparing the predicted distribution to the age-specific incidence data for colon and prostate carcinomas collected by the Surveillance, Epidemiology and End Results network of 17 cancer registries. We found that colon carcinoma age-specific incidence data is consistent with an extreme value distribution, while prostate carcinomas age-specific incidence data generally follows the distribution. This model indicates that both colon and prostate carcinomas only occur in a subset of the population (22% for prostate and 13.5% for colon. Because of their very general nature, extreme value distributions might be applicable to understanding other chronic human diseases.

  3. Uneven distribution of NG2 cells in the rat cerebellar vermis and changes in aging

    Directory of Open Access Journals (Sweden)

    S. Lomoio

    2012-06-01

    Full Text Available We describe by NG2 (neuron-glia chondroitin sulphate proteoglycan 2 immunocytochemistry an uneven distribution of NG2 glial cells in the rat cerebellum, being them more represented in the central lobules of the cerebellar vermis, belonging to the cerebrocerebellum. The cerebellar distribution of NG2 cells changes in aging rats, in which the area where the cells appear to be densely scattered throughout all cerebellar layers involves also more rostral and caudal lobules. In addition, in aging rats, in the most rostral and caudal lobules belonging to the spinocerebellum, punctate reaction product is present at the apical pole of Purkinje cells, i.e. in the area where the majority of synapses between olivary climbing fibers and Purkinje cells occur. Data suggest that the different distribution of NG2 cells is correlated to differences in physiology among cerebellar areas and reflects changes during aging.

  4. Transit-time and age distributions for nonlinear time-dependent compartmental systems.

    Science.gov (United States)

    Metzler, Holger; Müller, Markus; Sierra, Carlos A

    2018-02-06

    Many processes in nature are modeled using compartmental systems (reservoir/pool/box systems). Usually, they are expressed as a set of first-order differential equations describing the transfer of matter across a network of compartments. The concepts of age of matter in compartments and the time required for particles to transit the system are important diagnostics of these models with applications to a wide range of scientific questions. Until now, explicit formulas for transit-time and age distributions of nonlinear time-dependent compartmental systems were not available. We compute densities for these types of systems under the assumption of well-mixed compartments. Assuming that a solution of the nonlinear system is available at least numerically, we show how to construct a linear time-dependent system with the same solution trajectory. We demonstrate how to exploit this solution to compute transit-time and age distributions in dependence on given start values and initial age distributions. Furthermore, we derive equations for the time evolution of quantiles and moments of the age distributions. Our results generalize available density formulas for the linear time-independent case and mean-age formulas for the linear time-dependent case. As an example, we apply our formulas to a nonlinear and a linear version of a simple global carbon cycle model driven by a time-dependent input signal which represents fossil fuel additions. We derive time-dependent age distributions for all compartments and calculate the time it takes to remove fossil carbon in a business-as-usual scenario.

  5. Research on bimodal particle extinction coefficient during Brownian coagulation and condensation for the entire particle size regime

    International Nuclear Information System (INIS)

    Tang Hong; Lin Jianzhong

    2011-01-01

    The extinction coefficient of atmospheric aerosol particles influences the earth’s radiation balance directly or indirectly, and it can be determined by the scattering and absorption characteristics of aerosol particles. The problem of estimating the change of extinction coefficient due to time evolution of bimodal particle size distribution is studied, and two improved methods for calculating the Brownian coagulation coefficient and the condensation growth rate are proposed, respectively. Through the improved method based on Otto kernel, the Brownian coagulation coefficient can be expressed simply in powers of particle volume for the entire particle size regime based on the fitted polynomials of the mean enhancement function. Meanwhile, the improved method based on Fuchs–Sutugin kernel is developed to obtain the condensation growth rate for the entire particle size regime. And then, the change of the overall extinction coefficient of bimodal distributions undergoing Brownian coagulation and condensation can be estimated comprehensively for the entire particle size regime. Simulation experiments indicate that the extinction coefficients obtained with the improved methods coincide fairly well with the true values, which provide a simple, reliable, and general method to estimate the change of extinction coefficient for the entire particle size regime during the bimodal particle dynamic processes.

  6. The role of martensitic transformation on bimodal grain structure in ultrafine grained AISI 304L stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Sabooni, S., E-mail: s.sabooni@ma.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, 84156-83111 Isfahan (Iran, Islamic Republic of); Karimzadeh, F.; Enayati, M.H. [Department of Materials Engineering, Isfahan University of Technology, 84156-83111 Isfahan (Iran, Islamic Republic of); Ngan, A.H.W. [Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong (China)

    2015-06-11

    In the present study, metastable AISI 304L austenitic stainless steel samples were subjected to different cold rolling reductions from 70% to 93%, followed by annealing at 700 °C for 300 min to form ultrafine grained (UFG) austenite with different grain structures. Transmission electron microscopy (TEM) and nanoindentation were used to characterize the martensitic transformation, in order to relate it to the bimodal distribution of the austenite grain size after subsequent annealing. The results showed that the martensite morphology changed from lath type in the 60% rolled sample to a mixture of lath and dislocation-cell types in the higher rolling reductions. Calculation of the Gibbs free energy change during the reversion treatment showed that the reversion mechanism is shear controlled at the annealing temperature and so the morphology of the reverted austenite is completely dependent on the morphology of the deformation induced martensite. It was found that the austenite had a bimodal grain size distribution in the 80% rolled and annealed state and this is related to the existence of different types of martensite. Increasing the rolling reduction to 93% followed by annealing caused changing of the grain structure to a monomodal like structure, which was mostly covered with small grains of around 300 nm. The existence of bimodal austenite grain size in the 80% rolled and annealed 304L stainless steel led to the improvement of ductility while maintaining a high tensile strength in comparison with the 93% rolled and annealed sample.

  7. Mobile Education: Towards Affective Bi-modal Interaction for Adaptivity

    Directory of Open Access Journals (Sweden)

    Efthymios Alepis

    2009-04-01

    Full Text Available One important field where mobile technology can make significant contributions is education. However one criticism in mobile education is that students receive impersonal teaching. Affective computing may give a solution to this problem. In this paper we describe an affective bi-modal educational system for mobile devices. In our research we describe a novel approach of combining information from two modalities namely the keyboard and the microphone through a multi-criteria decision making theory.

  8. Hatching distribution and embryo mortality of eggs laid by broiler breeders of different ages

    Directory of Open Access Journals (Sweden)

    JG Almeida

    2008-06-01

    Full Text Available This study investigated the hatching distribution of eggs from broiler breeders of different ages in distinct periods of incubation. Eggs were incubated in a single-stage experimental incubator. A number of 3.510 eggs were distributed into 3 treatments with 13 replicates of 90 eggs each. Treatments corresponded to breeder age: young (34 weeks, intermediate-age (44 weeks and old (72 weeks breeders. Eggs were transferred to the hatcher at 432 incubation hours, hatching was first checked at 449 hours, after which the number of hatched chicks was counted every 6 hours up to 515 incubation hours. After each count, hatched chicks were removed from the hatcher. Data were submitted to analysis of variance using measures repeated. A significant interaction between breeder age and incubation time was found. The total period required to hatch all incubated fertile eggs was not influenced by breeder age, which, however, affected hatching distribution. Eggs from old breeders hatched later as compared to young and intermediate-age breeders. More than 71% of the eggs had already hatched at 485 incubation hours, and 94% at 491 hours. Eggs laid by old breeders presented higher infertility and total embryo mortality, resulting in lower hatching percentage.

  9. On the effect of segregation on intense bimodal bed load

    Directory of Open Access Journals (Sweden)

    Zrostlík Štěpán

    2017-01-01

    Full Text Available Open-channel two-phase flow above a granular mobile bed is studied experimentally and theoretically. In the two-phase flow, water serves as a carrying liquid for plastic grains transported as collisional contact load in the upper-stage plane bed regime. The investigation evaluates friction- and transport characteristics of the flow under the condition of intense collisional transport of grains and links them with the internal structure of the two-phase flow. The paper focusses on the effect of bimodal solids (mixed two fractions of grains of similar density and different size and shape on the flow characteristics and internal structure. Hence, experimental results obtained for the bimodal mixture are compared with results for individual grain fractions. The experiments show that the bimodal character of the transported solids affects the layered internal structure of the flow as a result of fraction segregation due primarily to gravity (kinetic sieving during transport. The segregation also affects the friction- and transport characteristics of intense bed load. In the paper, the effects are described and quantified.

  10. On the effect of segregation on intense bimodal bed load

    Science.gov (United States)

    Zrostlík, Štěpán; Matoušek, Václav

    Open-channel two-phase flow above a granular mobile bed is studied experimentally and theoretically. In the two-phase flow, water serves as a carrying liquid for plastic grains transported as collisional contact load in the upper-stage plane bed regime. The investigation evaluates friction- and transport characteristics of the flow under the condition of intense collisional transport of grains and links them with the internal structure of the two-phase flow. The paper focusses on the effect of bimodal solids (mixed two fractions of grains of similar density and different size and shape) on the flow characteristics and internal structure. Hence, experimental results obtained for the bimodal mixture are compared with results for individual grain fractions. The experiments show that the bimodal character of the transported solids affects the layered internal structure of the flow as a result of fraction segregation due primarily to gravity (kinetic) sieving during transport. The segregation also affects the friction- and transport characteristics of intense bed load. In the paper, the effects are described and quantified.

  11. Particle filtering with path sampling and an application to a bimodal ocean current model

    International Nuclear Information System (INIS)

    Weare, Jonathan

    2009-01-01

    This paper introduces a recursive particle filtering algorithm designed to filter high dimensional systems with complicated non-linear and non-Gaussian effects. The method incorporates a parallel marginalization (PMMC) step in conjunction with the hybrid Monte Carlo (HMC) scheme to improve samples generated by standard particle filters. Parallel marginalization is an efficient Markov chain Monte Carlo (MCMC) strategy that uses lower dimensional approximate marginal distributions of the target distribution to accelerate equilibration. As a validation the algorithm is tested on a 2516 dimensional, bimodal, stochastic model motivated by the Kuroshio current that runs along the Japanese coast. The results of this test indicate that the method is an attractive alternative for problems that require the generality of a particle filter but have been inaccessible due to the limitations of standard particle filtering strategies.

  12. Wear behavior of light-cured resin composites with bimodal silica nanostructures as fillers.

    Science.gov (United States)

    Wang, Ruili; Bao, Shuang; Liu, Fengwei; Jiang, Xiaoze; Zhang, Qinghong; Sun, Bin; Zhu, Meifang

    2013-12-01

    To enhance wear behavior of resin composites, bimodal silica nanostructures including silica nanoparticles and silica nanoclusters were prepared and proposed as fillers. The silica nanoclusters, a combination of individually dispersed silica nanoparticles and their agglomerations, with size distribution of 0.07-2.70 μm, were fabricated by the coupling reaction between amino and epoxy functionalized silica nanoparticles, which were obtained by the surface modification of silica nanoparticles (~70 nm) using 3-aminopropyl triethoxysilane (APTES) and 3-glycidoxypropyl trimethoxysilane (GPS) as coupling agents, respectively. Silica nanoparticles and nanoclusters were then silanized with 3-methacryloxypropyl trimethoxysilane (γ-MPS) to prepare composites by mixing with bisphenol A glycerolate dimethacrylate (Bis-GMA) and tri (ethylene glycol) dimethacrylate (TEGDMA). Experimental composites with various filler compositions were prepared and their wear behaviors were assessed in this work. The results suggested that composites with increasing addition of silica nanoparticles in co-fillers possessed lower wear volume and smoother worn surface. Particularly, the composite 53:17 with the optimum weight ratio of silica nanoparticles and silica nanoclusters presented the excellent wear behavior with respect to that of the commercial Esthet-X, although the smallest wear volume was achieved by Z350 XT. The introduction of bimodal silica nanostructures as fillers might provide a new sight for the design of resin composites with significantly improved wear resistance. Crown Copyright © 2013. All rights reserved.

  13. Cobalt Distribution and Speciation: Effect of Aging, Intermittent Submergence, In situ Rice Roots

    Science.gov (United States)

    The speciation and distribution of cobalt (Co) in soils is poorly understood. This study was conducted using X-ray absorption spectroscopy (XAS) techniques to examine the influence of soluble Co(II) aging, submergence-dried cycling, and the presence of in vivo rice roots on the...

  14. Perspectives on the age and distribution of large wood in riparian carbon pools

    Science.gov (United States)

    Richard P. Guyette; William G. Cole; Daniel C. Dey; Rose-Marie Muzkia

    2002-01-01

    Most knowledge of carbon budgets is derived from the productivity and sequestration of carbon in terrestrial and marine ecosystems. Less is known of carbon stored in riparian areas associated with lakes and rivers. Case studies of the age distribution of carbon in aquatic large wood (C1w) from two different landscapes with different drainage...

  15. Age and distribution of an evergreen clonal shrub in the Coweeta basin: Rhododendron maximum L

    Science.gov (United States)

    Katherine J. Elliott; James M. Vose

    2012-01-01

    Rhododendron maximum L. is an evergreen, clonal shrub that forms a dominant sub-canopy layer and is a key species in southern Appalachian forests. We investigated the age and distribution of R. maximum across the Coweeta Basin, a 1626 ha watershed in western North Carolina. We selected 16 perennial, second-order streams and used a Global Positioning System to establish...

  16. Description of age, sex and site distribution of large bowel cancer in ...

    African Journals Online (AJOL)

    Aims/Objective: To determine the distribution of bowel cancer with special emphasis on age, sex and site. Methods: One hundred and sixty cases of histologically confirmed large bowel cancers at Jos University Teaching Hospital between January 1991 – December 2000 were reviewed. The records were collected from the ...

  17. Implications of differential age distribution of disease-associated meningococcal lineages for vaccine development

    NARCIS (Netherlands)

    Brehony, Carina; Trotter, Caroline L.; Ramsay, Mary E.; Chandra, Manosree; Jolley, Keith A.; van der Ende, Arie; Carion, Françoise; Berthelsen, Lene; Hoffmann, Steen; Harðardóttir, Hjördís; Vazquez, Julio A.; Murphy, Karen; Toropainen, Maija; Caniça, Manuela; Ferreira, Eugenia; Diggle, Mathew; Edwards, Giles F.; Taha, Muhamed-Kheir; Stefanelli, Paola; Kriz, Paula; Gray, Steve J.; Fox, Andrew J.; Jacobsson, Susanne; Claus, Heike; Vogel, Ulrich; Tzanakaki, Georgina; Heuberger, Sigrid; Caugant, Dominique A.; Frosch, Matthias; Maiden, Martin C. J.

    2014-01-01

    New vaccines targeting meningococci expressing serogroup B polysaccharide have been developed, with some being licensed in Europe. Coverage depends on the distribution of disease-associated genotypes, which may vary by age. It is well established that a small number of hyperinvasive lineages account

  18. Aging Management Guideline for commercial nuclear power plants: Power and distribution transformers

    International Nuclear Information System (INIS)

    Toman, G.; Gazdzinski, R.

    1994-05-01

    This Aging Management Guideline (AMG) provides recommended methods for effective detection and mitigation of age-related degradation mechanisms in power and distribution transformers important to license renewal in commercial nuclear power plants. The intent of this AMG to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner which allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein

  19. Aging Management Guideline for commercial nuclear power plants: Power and distribution transformers

    Energy Technology Data Exchange (ETDEWEB)

    Toman, G.; Gazdzinski, R. [Sandia National Labs., Albuquerque, NM (United States)

    1994-05-01

    This Aging Management Guideline (AMG) provides recommended methods for effective detection and mitigation of age-related degradation mechanisms in power and distribution transformers important to license renewal in commercial nuclear power plants. The intent of this AMG to assist plant maintenance and operations personnel in maximizing the safe, useful life of these components. It also supports the documentation of effective aging management programs required under the License Renewal Rule 10 CFR Part 54. This AMG is presented in a manner which allows personnel responsible for performance analysis and maintenance to compare their plant-specific aging mechanisms (expected or already experienced) and aging management program activities to the more generic results and recommendations presented herein.

  20. CCD ubvy photometry of the bimodal main-sequence cluster NGC 3680

    Energy Technology Data Exchange (ETDEWEB)

    Anthony-Twarog, B.J.; Twarog, B.A.; Shodhan, S. (Kansas Univ., Lawrence (USA))

    1989-11-01

    CCD uvby photometry for the intermediate age, southern open cluster, NGC 3680, is analyzed. For a reddening of E(b-y) = 0.034, a true cluster modulus of 9.74 + or - 0.20 and a cluster metallicity of Fe/H abundance = 0.10 + or - 0.09, based on 18 probable nonbinary members of the cluster brighter than V = 14. The color-magnitude diagram for the cluster suggests that, although the main sequence may be subject to the same bimodal distibution as NGC 752, the likely source in both clusters is a combination of binaries and a sharply curved turnoff. The color-magnitude diagram is compared to the theoretical isochrones of Bertelli et al. (1988), showing an age of (1.9 + or - 0.3) X 10 to the 9th yr. 27 refs.

  1. HOW THE U.S. PRISON BOOM HAS CHANGED THE AGE DISTRIBUTION OF THE PRISON POPULATION*

    Science.gov (United States)

    PORTER, LAUREN C.; BUSHWAY, SHAWN D.; TSAO, HUI-SHIEN; SMITH, HERBERT L.

    2017-01-01

    This article provides a demographic exposition of the changes in the U.S prison population during the period of mass incarceration that began in the late twentieth century. By drawing on data from the Survey of Inmates in State Correctional Facilities (1974–2004) for inmates 17–72 years of age (N = 336), we show that the age distribution shifted upward dramatically: Only 16 percent of the state prison population was 40 years old or older in 1974; by 2004, this percentage had doubled to 33 percent with the median age of prisoners rising from 27 to 34 years old. By using an estimable function approach, we find that the change in the age distribution of the prison population is primarily a cohort effect that is driven by the “enhanced” penal careers of the cohorts who hit young adulthood—the prime age of both crime and incarceration—when substance use was at its peak. Period-specific factors (e.g., proclivity for punishment and incidence of offense) do matter, but they seem to play out more across the life cycles of persons most affected in young adulthood (cohort effects) than across all age groups at one point in time (period effects). PMID:28936228

  2. HOW THE U.S. PRISON BOOM HAS CHANGED THE AGE DISTRIBUTION OF THE PRISON POPULATION.

    Science.gov (United States)

    Porter, Lauren C; Bushway, Shawn D; Tsao, Hui-Shien; Smith, Herbert L

    2016-02-01

    This article provides a demographic exposition of the changes in the U.S prison population during the period of mass incarceration that began in the late twentieth century. By drawing on data from the Survey of Inmates in State Correctional Facilities (1974-2004) for inmates 17-72 years of age ( N = 336), we show that the age distribution shifted upward dramatically: Only 16 percent of the state prison population was 40 years old or older in 1974; by 2004, this percentage had doubled to 33 percent with the median age of prisoners rising from 27 to 34 years old. By using an estimable function approach, we find that the change in the age distribution of the prison population is primarily a cohort effect that is driven by the "enhanced" penal careers of the cohorts who hit young adulthood-the prime age of both crime and incarceration-when substance use was at its peak. Period-specific factors (e.g., proclivity for punishment and incidence of offense) do matter, but they seem to play out more across the life cycles of persons most affected in young adulthood (cohort effects) than across all age groups at one point in time (period effects).

  3. X-ray fluorescence microscopic measurement of elemental distribution in the mouse retina with age.

    Science.gov (United States)

    Grubman, Alexandra; Guennel, Philipp; Vessey, Kirstan A; Jones, Michael W M; James, Simon A; de Jonge, Martin D; White, Anthony R; Fletcher, Erica L

    2016-10-01

    The biologically important metals such as zinc, copper and iron play key roles in retinal function, yet no study has mapped the spatio-temporal distribution of retinal biometals in healthy or diseased retina. We investigated a natural mouse model of retinal degeneration, the Cln6 nclf mouse. As dysfunctional metabolism of biometals is observed in the brains of these animals and deregulated metal homeostasis has been linked to retinal degeneration, we focused on mapping the elemental distribution in the healthy and Cln6 nclf mouse retina with age. Retinal and RPE elemental homeostasis was mapped in Cln6 nclf and C57BL6/J mice from 1 to 8 months of age using X-ray Fluorescence Microscopy at the Australian Synchrotron. In the healthy retina, we detected a progressive loss of phosphorus in the outer nuclear layer and significant reduction in iron in the inner segments of the photoreceptors. Further investigation revealed a unique elemental signature for each retinal layer, with high areal concentrations of iron and sulfur in the photoreceptor segments and calcium, phosphorus, zinc and potassium enrichment predominantly in the nuclear layers. The analysis of retinae from Cln6 nclf mice did not show significant temporal changes in elemental distributions compared to age matched controls, despite significant photoreceptor cell loss. Our data therefore demonstrates that retinal layers have unique elemental composition. Elemental distribution is, with few exceptions, stably maintained over time in healthy and Cln6 nclf mouse retina, suggesting conservation of elemental distribution is critical for basic retinal function with age and is not modulated by processes underlying retinal degeneration.

  4. Segmenting Bone Parts for Bone Age Assessment using Point Distribution Model and Contour Modelling

    Science.gov (United States)

    Kaur, Amandeep; Singh Mann, Kulwinder, Dr.

    2018-01-01

    Bone age assessment (BAA) is a task performed on radiographs by the pediatricians in hospitals to predict the final adult height, to diagnose growth disorders by monitoring skeletal development. For building an automatic bone age assessment system the step in routine is to do image pre-processing of the bone X-rays so that features row can be constructed. In this research paper, an enhanced point distribution algorithm using contours has been implemented for segmenting bone parts as per well-established procedure of bone age assessment that would be helpful in building feature row and later on; it would be helpful in construction of automatic bone age assessment system. Implementation of the segmentation algorithm shows high degree of accuracy in terms of recall and precision in segmenting bone parts from left hand X-Rays.

  5. Small Low Mass Advanced PBR's for Bi-Modal Operation

    Science.gov (United States)

    Ludewig, Hans; Todosow, Michael; Powell, James R.

    1994-07-01

    A preliminary assessment is made of a low mass bi-modal reactor for use as a propulsion unit and as a heat source for generating electricity. This reactor is based on the particle bed reactor (PBR) concept. It will be able to generate both thrust and electricity simultaneously. This assessment indicates that the reactor can generate approximately 6.8 (4) N of thrust using hydrogen as a coolant, and 100 KWe using a closed Brayton cycle (CBC) power conversion system. Two cooling paths pass through the reactor allowing simultaneous operation of both modes. The development of all the components for this reactor are within the experience base of the NTP project.

  6. Bifurcation Structures in a Bimodal Piecewise Linear Map

    Directory of Open Access Journals (Sweden)

    Anastasiia Panchuk

    2017-05-01

    Full Text Available In this paper we present an overview of the results concerning dynamics of a piecewise linear bimodal map. The organizing principles of the bifurcation structures in both regular and chaotic domains of the parameter space of the map are discussed. In addition to the previously reported structures, a family of regions closely related to the so-called U-sequence is described. The boundaries of distinct regions belonging to these structures are obtained analytically using the skew tent map and the map replacement technique.

  7. Behavioral responses to and brain distribution of morphine in mature adult and aged mice

    Energy Technology Data Exchange (ETDEWEB)

    Burton, C.K.; Ho, I.K.; Hoskins, B.

    1986-03-01

    Mature adult (3-6 mo old) and aged (2 yr old) male ICR mice were injected with 10 to 100 mg/kg morphine, s.c. The ED50 values for running behavior (as measured using Stoelting activity monitors and having each mouse serve as its own control) representing 5 times control activity was approximately 7.5 mg/kg for aged mice and approximately 17.5 mg/kg for the mature adults. The ED50 values for analgesia 1 hr after morphine administration using the tail-flick method (max. response time = 8 sec) were approx. 70 mg/kg for the aged mice and 15 mg/kg for the mature adults. One hour after injecting /sup 3/H-morphine at doses of 30 and 100 mg/kg, 0.13 and 0.14% of the doses appeared in brains of aged and mature adult mice, respectively. Regional distribution of the morphine was the same for both age groups. Expressed as percent of total brain morphine, it was as follows: cortex, 30%; midbrain, 18%; cerebellum, 17%; medulla, 12%; pons, 9%; striatum, 8% and periaqueductal gray, 6%. Expressed as g morphine/g tissue for the 2 doses, the distribution was; periaqueductal gray, 30 and 80; striatum, 9 and 34; medulla, 6 and 20 pons; 5 and 19; cerebellum, 4 and 13; midbrain 2.5 and 8.5 and cortex, 2 and 8. These results suggest that the differences in response to morphine by the two age groups were due to age-related differences in opioid receptor populations and/or affinities.

  8. Effect of meta-carborane on segmental dynamics in a bimodal Poly(dimethylsiloxane) network

    Energy Technology Data Exchange (ETDEWEB)

    Lewicki, J; Maxwell, R S; Patel, M; Herberg, J; Swain, A C; Liggat, J; Pethrick, R

    2008-06-11

    Bimodal networks of polydimethylsiloxane (PDMS) filled with varying amounts of icosahedral meta-carborane (m-CB) have been developed and characterized by broadband dielectric spectroscopy (BDS) and static {sup 1}H Multiple Quantum Nuclear Magnetic Resonance (MQ NMR). Both BDS and MQ NMR showed evidence for a decrease in the polymer chain dynamics. BDS spectra quantified a normal-mode relaxation near 40 Hz at 40 C. The frequency maximum observed for filled samples decreased with increasing m-CB content until contents greater than 5 wt. %. The width of the relaxation spectrum increased with the addition of small quantities of filler and decreased with filler contents greater that 5 wt. %. Agglomeration effects were observed at loadings greater than 5 wt % as manifest by the onset of low frequency Maxwell-Wagner-Sillars (MWS) processes. The MQ NMR data allowed the characterization of distributions of the residual dipolar couplings, <{Omega}{sub d}> and thus in the dynamic order parameter, Sb, consistent with the bimodal network architecture expected from the synthesis protocol used. Upon addition of less than 10 wt.% m-CB filler, the mean <{Omega}{sub d}> for the longer chains increased by 46% and the width of the distribution increased by 33%. The mean <{Omega}{sub d}> for the shorter chains increased by much less, indicative of preferential dispersion of the filler particles in the long chain domains of the network structure. We conclude that the mechanism of reinforcement is likely a free volume space filling at low loadings transitioning to complex molecular filler and polymer chain interaction phenomena at higher loadings.

  9. Distribution of Spinal Deformities/Diseases by Age and Sex in Aba and Owerri, Nigeria

    Directory of Open Access Journals (Sweden)

    2016-11-01

    Full Text Available Spinal deformity is an abnormal positioning /structure of the vertebral column. These deformities may be caused by degenerative spinal disease often followed by trauma. The study aimed at investigating the overall distribution of spinal deformities/diseases seen by orthopeadists in Aba and Owerri and to proffer preventive measures. The data for this work was source through hospital records and patients folder/files spanning a 5-year (2005-2009 period from selected orthopaedic specialist hospitals in Aba and Owerri metropolis. Information on patients\\' age, gender and diagnosis were collected, coded and analyzed descriptively. A total of 20901 orthopaedic cases were investigated out of which 1484 cases of spinal deformities/diseases were observed. Females (53.7% vs 46.3% were more affected compared to males. Among the spinal disorders studied, spondylosis/ spondylolisthesis (45.2% and low back pain (15.6% were found to be the most frequent occurring while spinal metastasis and osteoporosis of the vertebra each at 0.1% were the least occurring. Age distributions indicated that spondylosis/ spondylolisthesis, lumbago and Sciatica, featured more among age groups 41-60 years while scoliosis was more in 1-20 age groups. Early screening of these disorders in preschool and school children as well as the general population is necessary in other to appropriate adequate medical intervention since early onset of the disorders is evident. Proper ergonomic practice is also advocated.

  10. Estimating the distribution of probable age-at-death from dental remains of immature human fossils.

    Science.gov (United States)

    Shackelford, Laura L; Stinespring Harris, Ashley E; Konigsberg, Lyle W

    2012-02-01

    In two historic longitudinal growth studies, Moorrees et al. (Am J Phys Anthropol 21 (1963) 99-108; J Dent Res 42 (1963) 1490-1502) presented the "mean attainment age" for stages of tooth development for 10 permanent tooth types and three deciduous tooth types. These findings were presented graphically to assess the rate of tooth formation in living children and to age immature skeletal remains. Despite being widely cited, these graphical data are difficult to implement because there are no accompanying numerical values for the parameters underlying the growth data. This analysis generates numerical parameters from the data reported by Moorrees et al. by digitizing 358 points from these tooth formation graphs using DataThief III, version 1.5. Following the original methods, the digitized points for each age transition were conception-corrected and converted to the logarithmic scale to determine a median attainment age for each dental formation stage. These values are subsequently used to estimate age-at-death distributions for immature individuals using a single tooth or multiple teeth, including estimates for 41 immature early modern humans and 25 immature Neandertals. Within-tooth variance is calculated for each age estimate based on a single tooth, and a between-tooth component of variance is calculated for age estimates based on two or more teeth to account for the increase in precision that comes from using additional teeth. Finally, we calculate the relative probability of observing a particular dental formation sequence given known-age reference information and demonstrate its value in estimating age for immature fossil specimens. Copyright © 2011 Wiley Periodicals, Inc.

  11. Influence of pedestrian age and gender on spatial and temporal distribution of pedestrian crashes.

    Science.gov (United States)

    Toran Pour, Alireza; Moridpour, Sara; Tay, Richard; Rajabifard, Abbas

    2018-01-02

    Every year, about 1.24 million people are killed in traffic crashes worldwide and more than 22% of these deaths are pedestrians. Therefore, pedestrian safety has become a significant traffic safety issue worldwide. In order to develop effective and targeted safety programs, the location- and time-specific influences on vehicle-pedestrian crashes must be assessed. The main purpose of this research is to explore the influence of pedestrian age and gender on the temporal and spatial distribution of vehicle-pedestrian crashes to identify the hotspots and hot times. Data for all vehicle-pedestrian crashes on public roadways in the Melbourne metropolitan area from 2004 to 2013 are used in this research. Spatial autocorrelation is applied in examining the vehicle-pedestrian crashes in geographic information systems (GIS) to identify any dependency between time and location of these crashes. Spider plots and kernel density estimation (KDE) are then used to determine the temporal and spatial patterns of vehicle-pedestrian crashes for different age groups and genders. Temporal analysis shows that pedestrian age has a significant influence on the temporal distribution of vehicle-pedestrian crashes. Furthermore, men and women have different crash patterns. In addition, results of the spatial analysis shows that areas with high risk of vehicle-pedestrian crashes can vary during different times of the day for different age groups and genders. For example, for those between ages 18 and 65, most vehicle-pedestrian crashes occur in the central business district (CBD) during the day, but between 7:00 p.m. and 6:00 a.m., crashes among this age group occur mostly around hotels, clubs, and bars. This research reveals that temporal and spatial distributions of vehicle-pedestrian crashes vary for different pedestrian age groups and genders. Therefore, specific safety measures should be in place during high crash times at different locations for different age groups and genders to

  12. Global distribution of mean age of stratospheric air from MIPAS SF6 measurements

    Directory of Open Access Journals (Sweden)

    H. Fischer

    2008-02-01

    Full Text Available Global distributions of profiles of sulphur hexafluoride (SF6 have been retrieved from limb emission spectra recorded by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS on Envisat covering the period September 2002 to March 2004. Individual SF6 profiles have a precision of 0.5 pptv below 25 km altitude and a vertical resolution of 4–6 km up to 35 km altitude. These data have been validated versus in situ observations obtained during balloon flights of a cryogenic whole-air sampler. For the tropical troposphere a trend of 0.230±0.008 pptv/yr has been derived from the MIPAS data, which is in excellent agreement with the trend from ground-based flask and in situ measurements from the National Oceanic and Atmospheric Administration Earth System Research Laboratory, Global Monitoring Division. For the data set currently available, based on at least three days of data per month, monthly 5° latitude mean values have a 1σ standard error of 1%. From the global SF6 distributions, global daily and monthly distributions of the apparent mean age of air are inferred by application of the tropical tropospheric trend derived from MIPAS data. The inferred mean ages are provided for the full globe up to 90° N/S, and have a 1σ standard error of 0.25 yr. They range between 0 (near the tropical tropopause and 7 years (except for situations of mesospheric intrusions and agree well with earlier observations. The seasonal variation of the mean age of stratospheric air indicates episodes of severe intrusion of mesospheric air during each Northern and Southern polar winter observed, long-lasting remnants of old, subsided polar winter air over the spring and summer poles, and a rather short period of mixing with midlatitude air and/or upward transport during fall in October/November (NH and April/May (SH, respectively, with small latitudinal gradients, immediately before the new polar vortex starts to form. The mean age distributions further

  13. Prevalence, Vascular Distribution, and Multiterritorial Extent of Subclinical Atherosclerosis in a Middle-Aged Cohort

    DEFF Research Database (Denmark)

    Fernández-Friera, Leticia; Peñalvo, José L; Fernández-Ortiz, Antonio

    2015-01-01

    BACKGROUND: Data are limited on the presence, distribution, and extent of subclinical atherosclerosis in middle-aged populations. METHODS AND RESULTS: The PESA (Progression of Early Subclinical Atherosclerosis) study prospectively enrolled 4184 asymptomatic participants 40 to 54 years of age (mean...... Study (FHS) 10-year risk, subclinical disease was detected in 58%, with intermediate or generalized disease in 36%. When longer-term risk was assessed (30-year FHS), 83% of participants at high risk had atherosclerosis, with 66% classified as intermediate or generalized. CONCLUSIONS: Subclinical...... age, 45.8 years; 63% male) to evaluate the systemic extent of atherosclerosis in the carotid, abdominal aortic, and iliofemoral territories by 2-/3-dimensional ultrasound and coronary artery calcification by computed tomography. The extent of subclinical atherosclerosis, defined as presence of plaque...

  14. Active bone marrow distribution as a function of age in humans

    International Nuclear Information System (INIS)

    Cristy, M.

    1981-01-01

    In response to the need for better quantitative estimates of the regional distribution of the active bone marrow organ in infants and children, a method using various anatomical data has been developed. The method, a refinement of that of Atkinson (1962), predicts that in the newborn 27.8% of the active marrow in the body resides in the skull and 20.7% resides in the lower limbs. Atkinson's method predicts 7.0% in the skull and 38.9% in the lower limbs. According to the experimental data of Hudson (1965) involving 16 late-term foetuses and newborns, there is 29.5% (+- 4.2%) in the skull and 23.7% (+-2.2%) in the lower limbs. The values from the new method are much closer to experimental values in both bone groups. The values for the newborn and age one year predicted by the new method were adjusted after comparison with the experimental data for the newborn. Newer information on marrow cellularity was also incorporated into the method presented here, so that the distribution calculated here for the adult differs somewhat from those calculated by others. Overall, this adult distribution agrees more closely with published distributions based on 59 Fe studies than do the earlier distributions. (author)

  15. Mapping post-disturbance stand age distribution in Siberian larch forest based on a novel method

    Science.gov (United States)

    Chen, D.; Loboda, T. V.; Krylov, A.; Potapov, P.

    2014-12-01

    The Siberian larch forest, which accounts for nearly 20% of the global boreal forest biome, is unique, important, yet significantly understudied. These deciduous needleleaf forests with a single species dominance over a large continuous area are not found anywhere except the extreme continental zones of Siberia and the Russian Far East. Most of these forests are located in remote and sparsely populated areas and, therefore, little is known about spatial variability of their structure and dynamics. Wall-to-wall repeated observations of this area are available only since the 2000s. Previously, we developed methods for reconstruction of stand-age distribution from a sample of 1980-2000 disturbances in Landsat TM and ETM+ imagery. However, availability of those images in Siberian larch forests is particularly limited. Built upon the hypothesis that the spectral characteristics of the disturbed forest in the region change with time consistently, this paper proposes a novel method utilizing the newly released Global Forest Change (GFC) 2000-2012 dataset. We exploit the data-rich era of annual forest disturbance samples identified between 2000 and 2012 in the Siberian larch forest by the GFC dataset to build a robust training set of spectral signatures from regrowing larch forests as they appear in Landsat imagery in 2012. The extracted statistics are ingested into a random forest, which predicts the approximate stand age for every forested pixel in the circa 2000 composite. After merging the estimated stand age distribution for 1989-2000 with the observed disturbance records for 2001-2012, a gap-free 30 m resolution 24-year long record of stand age distribution is obtained. A preliminary accuracy assessment against the Advanced Very High Resolution Radiometer (AVHRR) burned area product suggested satisfactory performance of the proposed method.

  16. Atom probe tomography of secondary γ′ precipitation in a single crystal Ni-based superalloy after isothermal aging at 1100 °C

    Energy Technology Data Exchange (ETDEWEB)

    Tan, X.P., E-mail: xptan1985@gmail.com [IM 2NP, UMR 7334 CNRS, Université Aix-Marseille, 13397 Marseille Cedex 20 (France); Mangelinck, D.; Perrin-Pellegrino, C. [IM 2NP, UMR 7334 CNRS, Université Aix-Marseille, 13397 Marseille Cedex 20 (France); Rougier, L. [LSMX, MXG, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne (Switzerland); Gandin, Ch.-A. [CEMEF, UMR 7635 CNRS, MINES ParisTech, 06904 Sophia Antipolis (France); Jacot, A. [LSMX, MXG, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne (Switzerland); Ponsen, D.; Jaquet, V. [Snecma-SAFRAN Group, Service YQGC, 92702 Colombes (France)

    2014-10-25

    Highlights: • Bimodal size distribution of γ′ precipitates occurs after isothermal aging at 1100 °C. • Characterization of secondary γ′ by atom probe tomography. • It is proposed that the secondary γ′ occurs via a non-classical nucleation. • The coarsening of secondary γ′ precipitates well obeys the classical LSW theory. - Abstract: Secondary γ′ precipitation in a commercial single crystal Ni-based superalloy after the 1100 °C isothermal aging has been investigated by atom probe tomography. After the isothermal aging for 300 s, 1800 s and 3600 s, a bimodal size distribution of larger primary γ′ precipitates and numerous smaller secondary γ′ precipitates was obtained. It is proposed that the secondary γ′ precipitated via a non-classical nucleation mode. The coarsening of secondary γ′ precipitates well obeys the classical LSW theory.

  17. NONLINEAR COLOR-METALLICITY RELATIONS OF GLOBULAR CLUSTERS. II. A TEST ON THE NONLINEARITY SCENARIO FOR COLOR BIMODALITY USING THE u-BAND COLORS: THE CASE OF M87 (NGC 4486)

    International Nuclear Information System (INIS)

    Yoon, Suk-Jin; Lee, Sang-Yoon; Kim, Hak-Sub; Cho, Jaeil; Chung, Chul; Sohn, Sangmo T.; Blakeslee, John P.

    2011-01-01

    The optical color distributions of globular clusters (GCs) in most large elliptical galaxies are bimodal. Based on the assumed linear relationship between GC colors and their metallicities, the bimodality has been taken as evidence of two GC subsystems with different metallicities in each galaxy and has led to a number of theories in the context of galaxy formation. More recent observations and modeling of GCs, however, suggests that the color-metallicity relations (CMRs) are inflected, and thus colors likely trace metallicities in a nonlinear manner. The nonlinearity could produce bimodal color distributions from a broad underlying metallicity spread, even if it is unimodal. Despite the far-reaching implications, whether CMRs are nonlinear and whether the nonlinearity indeed causes the color bimodality are still open questions. Given that the spectroscopic refinement of CMRs is still very challenging, we here propose a new photometric technique to probe the possible nonlinear nature of CMRs. In essence, a color distribution of GCs is a 'projected' distribution of their metallicities. Since the form of CMRs hinges on which color is used, the shape of color distributions varies depending significantly on the colors. Among other optical colors, the u-band related colors (e.g., u – g and u – z) are theoretically predicted to exhibit significantly less inflected CMRs than other preferred CMRs (e.g., for g – z). As a case study, we performed the Hubble Space Telescope (HST)/WFPC2 archival u-band photometry for the M87 (NGC 4486) GC system with confirmed color bimodality. We show that the u-band color distributions are significantly different from that of g – z and consistent with our model predictions. With more u-band measurements, this method will support or rule out the nonlinear CMR scenario for the origin of GC color bimodality with high confidence. The HST/WFC3 observations in F336W for nearby large elliptical galaxies are highly anticipated in this regard.

  18. β-Amyloid burden in healthy aging: regional distribution and cognitive consequences.

    Science.gov (United States)

    Rodrigue, K M; Kennedy, K M; Devous, M D; Rieck, J R; Hebrank, A C; Diaz-Arrastia, R; Mathews, D; Park, D C

    2012-02-07

    Several lines of evidence suggest that pathologic changes underlying Alzheimer disease (AD) begin years prior to the clinical expression of the disease, underscoring the need for studies of cognitively healthy adults to capture these early changes. The overall goal of the current study was to map the cortical distribution of β-amyloid (Aβ) in a healthy adult lifespan sample (aged 30-89), and to assess the relationship between elevated amyloid and cognitive performance across multiple domains. A total of 137 well-screened and cognitively normal adults underwent Aβ PET imaging with radiotracer (18)F-florbetapir. Aβ load was estimated from 8 cortical regions. Participants were genotyped for APOE and tested for processing speed, working memory, fluid reasoning, episodic memory, and verbal ability. Aβ deposition is distributed differentially across the cortex and progresses at varying rates with age across cortical brain regions. A subset of cognitively normal adults aged 60 and over show markedly elevated deposition, and also had a higher rate of APOE ε4 (38%) than nonelevated adults (19%). Aβ burden was linked to poorer cognitive performance on measures of processing speed, working memory, and reasoning. Even in a highly selected lifespan sample of adults, Aβ deposition is apparent in some adults and is influenced by APOE status. Greater amyloid burden was related to deleterious effects on cognition, suggesting that subtle cognitive changes accrue as amyloid progresses.

  19. Relating Water Quality and Age in Drinking Water Distribution Systems Using Self-Organising Maps

    Directory of Open Access Journals (Sweden)

    E.J. Mirjam Blokker

    2016-04-01

    Full Text Available Understanding and managing water quality in drinking water distribution system is essential for public health and wellbeing, but is challenging due to the number and complexity of interacting physical, chemical and biological processes occurring within vast, deteriorating pipe networks. In this paper we explore the application of Self Organising Map techniques to derive such understanding from international data sets, demonstrating how multivariate, non-linear techniques can be used to identify relationships that are not discernible using univariate and/or linear analysis methods for drinking water quality. The paper reports on how various microbial parameters correlated with modelled water ages and were influenced by water temperatures in three drinking water distribution systems.

  20. Optimal Vaccine Distribution Strategy for Different Age Groups of Population: A Differential Evolution Algorithm Approach

    Directory of Open Access Journals (Sweden)

    Xiao-Min Hu

    2014-01-01

    Full Text Available Vaccination is one of the effective ways for protecting susceptible individuals from infectious diseases. Different age groups of population have different vulnerability to the disease and different contact frequencies. In order to achieve the maximum effects, the distribution of vaccine doses to the groups of individuals needs to be optimized. In this paper, a differential evolution (DE algorithm is proposed to address the problem. The performance of the proposed algorithm has been tested by a classical infectious disease transmission model and a series of simulations have been made. The results show that the proposed algorithm can always obtain the best vaccine distribution strategy which can minimize the number of infectious individuals during the epidemic outbreak. Furthermore, the effects of vaccination on different days and the vaccine coverage percentages have also been discussed.

  1. Mapping for maternal and newborn health: the distributions of women of childbearing age, pregnancies and births.

    Science.gov (United States)

    Tatem, Andrew J; Campbell, James; Guerra-Arias, Maria; de Bernis, Luc; Moran, Allisyn; Matthews, Zoë

    2014-01-04

    The health and survival of women and their new-born babies in low income countries has been a key priority in public health since the 1990s. However, basic planning data, such as numbers of pregnancies and births, remain difficult to obtain and information is also lacking on geographic access to key services, such as facilities with skilled health workers. For maternal and newborn health and survival, planning for safer births and healthier newborns could be improved by more accurate estimations of the distributions of women of childbearing age. Moreover, subnational estimates of projected future numbers of pregnancies are needed for more effective strategies on human resources and infrastructure, while there is a need to link information on pregnancies to better information on health facilities in districts and regions so that coverage of services can be assessed. This paper outlines demographic mapping methods based on freely available data for the production of high resolution datasets depicting estimates of numbers of people, women of childbearing age, live births and pregnancies, and distribution of comprehensive EmONC facilities in four large high burden countries: Afghanistan, Bangladesh, Ethiopia and Tanzania. Satellite derived maps of settlements and land cover were constructed and used to redistribute areal census counts to produce detailed maps of the distributions of women of childbearing age. Household survey data, UN statistics and other sources on growth rates, age specific fertility rates, live births, stillbirths and abortions were then integrated to convert the population distribution datasets to gridded estimates of births and pregnancies. These estimates, which can be produced for current, past or future years based on standard demographic projections, can provide the basis for strategic intelligence, planning services, and provide denominators for subnational indicators to track progress. The datasets produced are part of national midwifery

  2. Gaze-independent ERP-BCIs: augmenting performance through location-congruent bimodal stimuli

    Science.gov (United States)

    Thurlings, Marieke E.; Brouwer, Anne-Marie; Van Erp, Jan B. F.; Werkhoven, Peter

    2014-01-01

    Gaze-independent event-related potential (ERP) based brain-computer interfaces (BCIs) yield relatively low BCI performance and traditionally employ unimodal stimuli. Bimodal ERP-BCIs may increase BCI performance due to multisensory integration or summation in the brain. An additional advantage of bimodal BCIs may be that the user can choose which modality or modalities to attend to. We studied bimodal, visual-tactile, gaze-independent BCIs and investigated whether or not ERP components’ tAUCs and subsequent classification accuracies are increased for (1) bimodal vs. unimodal stimuli; (2) location-congruent vs. location-incongruent bimodal stimuli; and (3) attending to both modalities vs. to either one modality. We observed an enhanced bimodal (compared to unimodal) P300 tAUC, which appeared to be positively affected by location-congruency (p = 0.056) and resulted in higher classification accuracies. Attending either to one or to both modalities of the bimodal location-congruent stimuli resulted in differences between ERP components, but not in classification performance. We conclude that location-congruent bimodal stimuli improve ERP-BCIs, and offer the user the possibility to switch the attended modality without losing performance. PMID:25249947

  3. Nonlatching positive feedback enables robust bimodality by decoupling expression noise from the mean

    Science.gov (United States)

    Razooky, Brandon S.; Cao, Youfang; Hansen, Maike M. K.; Perelson, Alan S.; Simpson, Michael L.

    2017-01-01

    Fundamental to biological decision-making is the ability to generate bimodal expression patterns where 2 alternate expression states simultaneously exist. Here, we use a combination of single-cell analysis and mathematical modeling to examine the sources of bimodality in the transcriptional program controlling HIV’s fate decision between active replication and viral latency. We find that the HIV transactivator of transcription (Tat) protein manipulates the intrinsic toggling of HIV’s promoter, the long terminal repeat (LTR), to generate bimodal ON-OFF expression and that transcriptional positive feedback from Tat shifts and expands the regime of LTR bimodality. This result holds for both minimal synthetic viral circuits and full-length virus. Strikingly, computational analysis indicates that the Tat circuit’s noncooperative “nonlatching” feedback architecture is optimized to slow the promoter’s toggling and generate bimodality by stochastic extinction of Tat. In contrast to the standard Poisson model, theory and experiment show that nonlatching positive feedback substantially dampens the inverse noise-mean relationship to maintain stochastic bimodality despite increasing mean expression levels. Given the rapid evolution of HIV, the presence of a circuit optimized to robustly generate bimodal expression appears consistent with the hypothesis that HIV’s decision between active replication and latency provides a viral fitness advantage. More broadly, the results suggest that positive-feedback circuits may have evolved not only for signal amplification but also for robustly generating bimodality by decoupling expression fluctuations (noise) from mean expression levels. PMID:29045398

  4. Nonlatching positive feedback enables robust bimodality by decoupling expression noise from the mean

    Energy Technology Data Exchange (ETDEWEB)

    Razooky, Brandon S. [Rockefeller Univ., New York, NY (United States). Lab. of Virology and Infectious Disease; Gladstone Institutes (Virology and Immunology), San Francisco, CA (United States); Univ. of California, San Francisco, CA (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS); Univ. of Tennessee, Knoxville, TN (United States). Bredesen Center for Interdisciplinary; Cao, Youfang [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hansen, Maike M. K. [Gladstone Institutes (Virology and Immunology), San Francisco, CA (United States); Perelson, Alan S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Simpson, Michael L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Science (CNMS); Univ. of Tennessee, Knoxville, TN (United States). Bredesen Center for Interdisciplinary; Weinberger, Leor S. [Gladstone Institutes (Virology and Immunology), San Francisco, CA (United States); Univ. of California, San Francisco, CA (United States). Dept. of Biochemistry and Biophysics; Univ. of California, San Francisco, CA (United States). QB3: California Inst. of Quantitative Biosciences; Univ. of California, San Francisco, CA (United States). Dept. of Pharmaceutical Chemistry

    2017-10-18

    Fundamental to biological decision-making is the ability to generate bimodal expression patterns where two alternate expression states simultaneously exist. Here in this study, we use a combination of single-cell analysis and mathematical modeling to examine the sources of bimodality in the transcriptional program controlling HIV’s fate decision between active replication and viral latency. We find that the HIV Tat protein manipulates the intrinsic toggling of HIV’s promoter, the LTR, to generate bimodal ON-OFF expression, and that transcriptional positive feedback from Tat shifts and expands the regime of LTR bimodality. This result holds for both minimal synthetic viral circuits and full-length virus. Strikingly, computational analysis indicates that the Tat circuit’s non-cooperative ‘non-latching’ feedback architecture is optimized to slow the promoter’s toggling and generate bimodality by stochastic extinction of Tat. In contrast to the standard Poisson model, theory and experiment show that non-latching positive feedback substantially dampens the inverse noise-mean relationship to maintain stochastic bimodality despite increasing mean-expression levels. Given the rapid evolution of HIV, the presence of a circuit optimized to robustly generate bimodal expression appears consistent with the hypothesis that HIV’s decision between active replication and latency provides a viral fitness advantage. More broadly, the results suggest that positive-feedback circuits may have evolved not only for signal amplification but also for robustly generating bimodality by decoupling expression fluctuations (noise) from mean expression levels.

  5. Age and Sex Distribution of Intestinal Parasitic Infection Among HIV Infected Subjects in Abeokuta, Nigeria

    Directory of Open Access Journals (Sweden)

    Herbert Obi Okpala

    2004-03-01

    Full Text Available Intestinal parasitic infection has been a major source of disease in tropical countries especially among HIV patients. The distribution of intestinal parasite among two hundred and fifteen (215 subjects with mean age of 32 years, comprising of 35 HIV-seropositive and 180 HIV seronegative patients was carried out using microscopic method to examine their stool specimens for presence of trophozoites, ova, cysts, larvae and oocysts of intestinal parasites. Overall parasitic infection rate was 28.4%. Infection rate among HIV seropositve subjects (42.9% was statistically higher than that among HIV seronegative subjects (25.6% (P0.05. There was no statistically significant difference in the parasitic infection between HIV-seropositive males and females and among the various age groups (P>0.05. Adequate treatment, proper health education and good hygiene will help in reducing intestinal parasitic infection

  6. Crack Risk Evaluation of Early Age Concrete Based on the Distributed Optical Fiber Temperature Sensing

    Directory of Open Access Journals (Sweden)

    Nannan Shi

    2016-01-01

    Full Text Available Cracks often appear in concrete arch dams, due to the thermal stress and low tensile strength of early age concrete. There are three commonly used temperature controlling measures: controlling the casting temperature, burying cooling pipe, and protecting the surface. However, because of the difficulty to obtain accurate temperature and thermal stress field of the concrete, the rationality and economy of these measures are not assessed validly before and after construction. In this paper, a crack risk evaluation system for early age concrete is established, including distributed optical fiber temperature sensing (DTS, prediction of temperature and stress fields, and crack risk evaluation. Based on the DTS temperature data, the back-analysis method is applied to retrieve the thermal parameters of concrete. Then, the temperature and thermal stress of early age concrete are predicted using the reversed thermal parameters, as well as the laboratory test parameters. Finally, under the proposed cracking risk evaluation principle, the cracking risk level of each concrete block is given; the preliminary and later temperature controlling measures were recommended, respectively. The application of the proposed system in Xiluodu super high arch dam shows that this system works effectively for preventing cracks of early age concrete.

  7. Red blood cell distribution width: Genetic evidence for aging pathways in 116,666 volunteers.

    Directory of Open Access Journals (Sweden)

    Luke C Pilling

    Full Text Available Variability in red blood cell volumes (distribution width, RDW increases with age and is strongly predictive of mortality, incident coronary heart disease and cancer. We investigated inherited genetic variation associated with RDW in 116,666 UK Biobank human volunteers.A large proportion RDW is explained by genetic variants (29%, especially in the older group (60+ year olds, 33.8%, <50 year olds, 28.4%. RDW was associated with 194 independent genetic signals; 71 are known for conditions including autoimmune disease, certain cancers, BMI, Alzheimer's disease, longevity, age at menopause, bone density, myositis, Parkinson's disease, and age-related macular degeneration. Exclusion of anemic participants did not affect the overall findings. Pathways analysis showed enrichment for telomere maintenance, ribosomal RNA, and apoptosis. The majority of RDW-associated signals were intronic (119 of 194, including SNP rs6602909 located in an intron of oncogene GAS6, an eQTL in whole blood.Although increased RDW is predictive of cardiovascular outcomes, this was not explained by known CVD or related lipid genetic risks, and a RDW genetic score was not predictive of incident disease. The predictive value of RDW for a range of negative health outcomes may in part be due to variants influencing fundamental pathways of aging.

  8. Isomap nonlinear dimensionality reduction and bimodality of Asian monsoon convection

    Science.gov (United States)

    Hannachi, A.; Turner, A. G.

    2013-04-01

    It is known that the empirical orthogonal function method is unable to detect possible nonlinear structure in climate data. Here, isometric feature mapping (Isomap), as a tool for nonlinear dimensionality reduction, is applied to 1958-2001 ERA-40 sea-level pressure anomalies to study nonlinearity of the Asian summer monsoon intraseasonal variability. Using the leading two Isomap time series, the probability density function is shown to be bimodal. A two-dimensional bivariate Gaussian mixture model is then applied to identify the monsoon phases, the obtained regimes representing enhanced and suppressed phases, respectively. The relationship with the large-scale seasonal mean monsoon indicates that the frequency of monsoon regime occurrence is significantly perturbed in agreement with conceptual ideas, with preference for enhanced convection on intraseasonal time scales during large-scale strong monsoons. Trend analysis suggests a shift in concentration of monsoon convection, with less emphasis on South Asia and more on the East China Sea.

  9. [What bimodal bilingual have to say about bilingual developing?

    Science.gov (United States)

    de Quadros, Ronice Müller; Lillo-Martin, Diane; Pichler, Deborah Chen

    2013-07-01

    The goal of this work is to present what our research with hearing children from Deaf parents, acquiring Brazilian Sign Language (Libras) and Portuguese, and American Sign Language (ASL) and English (Lillo-Martin et. al. 2010) have to say about bilingual development. The data analyzed in this study is part of the database of spontaneous interactions collected longitudinally, alternating contexts of sign and spoken languages. Moreover, there is data from experimental studies with tests in both pairs of languages that is incorporated to the present study. A general view about previous studies related to bimodal bilingual acquisition with hearing children, from "deaf" parents, will be presented. Then, we will show some linguistics aspects of this kind of acquisition found in our study and discuss about bilingual acquisition.

  10. Event-related potentials to visual, auditory, and bimodal (combined auditory-visual) stimuli.

    Science.gov (United States)

    Isoğlu-Alkaç, Ummühan; Kedzior, Karina; Keskindemirci, Gonca; Ermutlu, Numan; Karamursel, Sacit

    2007-02-01

    The purpose of this study was to investigate the response properties of event related potentials to unimodal and bimodal stimulations. The amplitudes of N1 and P2 were larger during bimodal evoked potentials (BEPs) than auditory evoked potentials (AEPs) in the anterior sites and the amplitudes of P1 were larger during BEPs than VEPs especially at the parieto-occipital locations. Responses to bimodal stimulation had longer latencies than responses to unimodal stimulation. The N1 and P2 components were larger in amplitude and longer in latency during the bimodal paradigm and predominantly occurred at the anterior sites. Therefore, the current bimodal paradigm can be used to investigate the involvement and location of specific neural generators that contribute to higher processing of sensory information. Moreover, this paradigm may be a useful tool to investigate the level of sensory dysfunctions in clinical samples.

  11. Saturated hydraulic conductivity model computed from bimodal water retention curves for a range of New Zealand soils

    Science.gov (United States)

    Pollacco, Joseph Alexander Paul; Webb, Trevor; McNeill, Stephen; Hu, Wei; Carrick, Sam; Hewitt, Allan; Lilburne, Linda

    2017-06-01

    Descriptions of soil hydraulic properties, such as the soil moisture retention curve, θ(h), and saturated hydraulic conductivities, Ks, are a prerequisite for hydrological models. Since the measurement of Ks is expensive, it is frequently derived from statistical pedotransfer functions (PTFs). Because it is usually more difficult to describe Ks than θ(h) from pedotransfer functions, Pollacco et al. (2013) developed a physical unimodal model to compute Ks solely from hydraulic parameters derived from the Kosugi θ(h). This unimodal Ks model, which is based on a unimodal Kosugi soil pore-size distribution, was developed by combining the approach of Hagen-Poiseuille with Darcy's law and by introducing three tortuosity parameters. We report here on (1) the suitability of the Pollacco unimodal Ks model to predict Ks for a range of New Zealand soils from the New Zealand soil database (S-map) and (2) further adaptations to this model to adapt it to dual-porosity structured soils by computing the soil water flux through a continuous function of an improved bimodal pore-size distribution. The improved bimodal Ks model was tested with a New Zealand data set derived from historical measurements of Ks and θ(h) for a range of soils derived from sandstone and siltstone. The Ks data were collected using a small core size of 10 cm diameter, causing large uncertainty in replicate measurements. Predictions of Ks were further improved by distinguishing topsoils from subsoil. Nevertheless, as expected, stratifying the data with soil texture only slightly improved the predictions of the physical Ks models because the Ks model is based on pore-size distribution and the calibrated parameters were obtained within the physically feasible range. The improvements made to the unimodal Ks model by using the new bimodal Ks model are modest when compared to the unimodal model, which is explained by the poor accuracy of measured total porosity. Nevertheless, the new bimodal model provides an

  12. Saturated hydraulic conductivity model computed from bimodal water retention curves for a range of New Zealand soils

    Directory of Open Access Journals (Sweden)

    J. A. P. Pollacco

    2017-06-01

    Full Text Available Descriptions of soil hydraulic properties, such as the soil moisture retention curve, θ(h, and saturated hydraulic conductivities, Ks, are a prerequisite for hydrological models. Since the measurement of Ks is expensive, it is frequently derived from statistical pedotransfer functions (PTFs. Because it is usually more difficult to describe Ks than θ(h from pedotransfer functions, Pollacco et al. (2013 developed a physical unimodal model to compute Ks solely from hydraulic parameters derived from the Kosugi θ(h. This unimodal Ks model, which is based on a unimodal Kosugi soil pore-size distribution, was developed by combining the approach of Hagen–Poiseuille with Darcy's law and by introducing three tortuosity parameters. We report here on (1 the suitability of the Pollacco unimodal Ks model to predict Ks for a range of New Zealand soils from the New Zealand soil database (S-map and (2 further adaptations to this model to adapt it to dual-porosity structured soils by computing the soil water flux through a continuous function of an improved bimodal pore-size distribution. The improved bimodal Ks model was tested with a New Zealand data set derived from historical measurements of Ks and θ(h for a range of soils derived from sandstone and siltstone. The Ks data were collected using a small core size of 10 cm diameter, causing large uncertainty in replicate measurements. Predictions of Ks were further improved by distinguishing topsoils from subsoil. Nevertheless, as expected, stratifying the data with soil texture only slightly improved the predictions of the physical Ks models because the Ks model is based on pore-size distribution and the calibrated parameters were obtained within the physically feasible range. The improvements made to the unimodal Ks model by using the new bimodal Ks model are modest when compared to the unimodal model, which is explained by the poor accuracy of measured total porosity. Nevertheless, the new bimodal

  13. A partial exponential lumped parameter model to evaluate groundwater age distributions and nitrate trends in long-screened wells

    Science.gov (United States)

    Jurgens, Bryant; Böhlke, John Karl; Kauffman, Leon J.; Belitz, Kenneth; Esser, Bradley K.

    2016-01-01

    A partial exponential lumped parameter model (PEM) was derived to determine age distributions and nitrate trends in long-screened production wells. The PEM can simulate age distributions for wells screened over any finite interval of an aquifer that has an exponential distribution of age with depth. The PEM has 3 parameters – the ratio of saturated thickness to the top and bottom of the screen and mean age, but these can be reduced to 1 parameter (mean age) by using well construction information and estimates of the saturated thickness. The PEM was tested with data from 30 production wells in a heterogeneous alluvial fan aquifer in California, USA. Well construction data were used to guide parameterization of a PEM for each well and mean age was calibrated to measured environmental tracer data (3H, 3He, CFC-113, and 14C). Results were compared to age distributions generated for individual wells using advective particle tracking models (PTMs). Age distributions from PTMs were more complex than PEM distributions, but PEMs provided better fits to tracer data, partly because the PTMs did not simulate 14C accurately in wells that captured varying amounts of old groundwater recharged at lower rates prior to groundwater development and irrigation. Nitrate trends were simulated independently of the calibration process and the PEM provided good fits for at least 11 of 24 wells. This work shows that the PEM, and lumped parameter models (LPMs) in general, can often identify critical features of the age distributions in wells that are needed to explain observed tracer data and nonpoint source contaminant trends, even in systems where aquifer heterogeneity and water-use complicate distributions of age. While accurate PTMs are preferable for understanding and predicting aquifer-scale responses to water use and contaminant transport, LPMs can be sensitive to local conditions near individual wells that may be inaccurately represented or missing in an aquifer-scale flow model.

  14. Water Collection and Distribution Systems in the Palermo Plain during the Middle Ages

    Directory of Open Access Journals (Sweden)

    Ioannis K. Kalavrouziotis

    2013-10-01

    Full Text Available It has been said that Palermo is short of available water. However, nothing could be more wrong. Well-documented Arab sources and narrative chronicles reported an abundance of groundwater resources in Palermo Plain since the Middle Ages. The scarcity of sources and surface water in the Palermo Plain, compared to the groundwater abundance, led the inhabitants to use groundwater both for irrigation and domestic usage through a complex and sustainable hydraulic system. Vertical and horizontal (qanāts wells, conveyed water towards gardens and public fountains making the Arabic Bal’harm (Palermo a flourishing town. When visitors walk through the streets of Palermo’s historical center, among Arab ruins and Baroque architecture, they hardly imagine that there is a wide and varied cultural heritage of underground cavities hidden in the basements where water flows in intricate networks fed from a numerous springs. Only in recent years was a part of this system brought to light. Moreover, the city still has a wide and fascinating water distribution system consisting of irrigation basin (gebbie, ingenious hydraulic machines named senie, and distribution chessboard of irrigation (saje and drinking water (catusi canals. The medieval water collection and distribution systems and their various components in the Palermo Plain are reviewed together with the influence of the Arab water management on environment.

  15. Extracting information on the spatial variability in erosion rate stored in detrital cooling age distributions in river sands

    Science.gov (United States)

    Braun, Jean; Gemignani, Lorenzo; van der Beek, Peter

    2018-03-01

    One of the main purposes of detrital thermochronology is to provide constraints on the regional-scale exhumation rate and its spatial variability in actively eroding mountain ranges. Procedures that use cooling age distributions coupled with hypsometry and thermal models have been developed in order to extract quantitative estimates of erosion rate and its spatial distribution, assuming steady state between tectonic uplift and erosion. This hypothesis precludes the use of these procedures to assess the likely transient response of mountain belts to changes in tectonic or climatic forcing. Other methods are based on an a priori knowledge of the in situ distribution of ages to interpret the detrital age distributions. In this paper, we describe a simple method that, using the observed detrital mineral age distributions collected along a river, allows us to extract information about the relative distribution of erosion rates in an eroding catchment without relying on a steady-state assumption, the value of thermal parameters or an a priori knowledge of in situ age distributions. The model is based on a relatively low number of parameters describing lithological variability among the various sub-catchments and their sizes and only uses the raw ages. The method we propose is tested against synthetic age distributions to demonstrate its accuracy and the optimum conditions for it use. In order to illustrate the method, we invert age distributions collected along the main trunk of the Tsangpo-Siang-Brahmaputra river system in the eastern Himalaya. From the inversion of the cooling age distributions we predict present-day erosion rates of the catchments along the Tsangpo-Siang-Brahmaputra river system, as well as some of its tributaries. We show that detrital age distributions contain dual information about present-day erosion rate, i.e., from the predicted distribution of surface ages within each catchment and from the relative contribution of any given catchment to the

  16. Incidence trends and age distribution of colorectal cancer by subsite in Guangzhou, 2000-2011.

    Science.gov (United States)

    Zhou, Qin; Li, Ke; Lin, Guo-Zhen; Shen, Ji-Chuan; Dong, Hang; Gu, Yu-Ting; Liu, Hua-Zhang

    2015-08-06

    Colorectal cancer (CRC) is the third most common cancer in China. The incidence of CRC has been increasing in recent years. The aim of this study was to explore the incidence trends and the age distribution of CRC by subsite in Guangzhou between 2000 and 2011. A total of 22,432 incident cases of CRC between 2000 and 2011 from Guangzhou Cancer Registry were identified. Crude incidence and age-standardized rates (ASRs), using the Segi's world standard population, were calculated for CRC and CRC subsites. The incidence trend was analyzed and the annual percentage change (APC) in incidence was calculated by using JoinPoint software. The crude incidence increased significantly from 23.4/10(5) in 2000 to 37.4/10(5) in 2011 for males and from 20.9/10(5) to 30.5/10(5) for females. The ASRs of CRC incidence stabilized during the period of 2000-2011 for both males and females. The ages at the onset of CRC for both males and females during 2010-2011 were significantly higher compared with those during 2000-2002 (males: t = 1.95, P = 0.05; females: t = 6.03, P 2000-2004 and by 1.68% annually (P = 0.03) during 2005-2011. For females aged 65 years and older, the CRC incidence increased by 5.77% annually (P = 0.03) during 2000-2004. There were no significant changes for the CRC incidences in males aged 49 and younger and 65 years and older and females aged 64 years and younger during 2000-2004, or for those in all females as well as males aged 49 years and younger and 65 years and older during 2005-2011. The percentage of colon cancer in all CRCs increased significantly for both males and females between the periods of 2000-2002 and 2010-2011. The ASRs of descending colon and sigmoid colon cancer incidences increased significantly for females during 2005-2011 (APC, 5.51% and 1.08%, respectively, both P 2000 and 2011 because of the aging, whereas the ASRs kept stable. The percentage of colon cancer in all CRCs increased significantly. Further surveillance

  17. The prevalence, age distribution and comorbidity of personality disorders in Australian women.

    Science.gov (United States)

    Quirk, Shae E; Berk, Michael; Pasco, Julie A; Brennan-Olsen, Sharon L; Chanen, Andrew M; Koivumaa-Honkanen, Heli; Burke, Lisa M; Jackson, Henry J; Hulbert, Carol; A Olsson, Craig; Moran, Paul; Stuart, Amanda L; Williams, Lana J

    2017-02-01

    We aimed to describe the prevalence and age distribution of personality disorders and their comorbidity with other psychiatric disorders in an age-stratified sample of Australian women aged ⩾25 years. Individual personality disorders (paranoid, schizoid, schizotypal, histrionic, narcissistic, borderline, antisocial, avoidant, dependent, obsessive-compulsive), lifetime mood, anxiety, eating and substance misuse disorders were diagnosed utilising validated semi-structured clinical interviews (Structured Clinical Interview for DSM-IV-TR Axis I Disorders, Research Version, Non-patient Edition and Structured Clinical Interview for DSM-IV Axis II Personality Disorders). The prevalence of personality disorders and Clusters were determined from the study population ( n = 768), and standardised to the Australian population using the 2011 Australian Bureau of Statistics census data. Prevalence by age and the association with mood, anxiety, eating and substance misuse disorders was also examined. The overall prevalence of personality disorders in women was 21.8% (95% confidence interval [CI]: 18.7, 24.9). Cluster C personality disorders (17.5%, 95% CI: 16.0, 18.9) were more common than Cluster A (5.3%, 95% CI: 3.5, 7.0) and Cluster B personality disorders (3.2%, 95% CI: 1.8, 4.6). Of the individual personality disorders, obsessive-compulsive (10.3%, 95% CI: 8.0, 12.6), avoidant (9.3%, 95% CI: 7.1, 11.5), paranoid (3.9%, 95% CI: 3.1, 4.7) and borderline (2.7%, 95% CI: 1.4, 4.0) were among the most prevalent. The prevalence of other personality disorders was low (⩽1.7%). Being younger (25-34 years) was predictive of having any personality disorder (odds ratio: 2.36, 95% CI: 1.18, 4.74), as was being middle-aged (odds ratio: 2.41, 95% CI: 1.23, 4.72). Among the strongest predictors of having any personality disorder was having a lifetime history of psychiatric disorders (odds ratio: 4.29, 95% CI: 2.90, 6.33). Mood and anxiety disorders were the most common comorbid

  18. Calculation of age-dependent dose conversion coefficients for radionuclides uniformly distributed in air

    International Nuclear Information System (INIS)

    Hung, Tran Van; Satoh, Daiki; Takahashi, Fumiaki; Tsuda, Shuichi; Endo, Akira; Saito, Kimiaki; Yamaguchi, Yasuhiro

    2005-02-01

    Age-dependent dose conversion coefficients for external exposure to photons emitted by radionuclides uniformly distributed in air were calculated. The size of the source region in the calculation was assumed to be effectively semi-infinite in extent. Firstly, organ doses were calculated with a series of age-specific MIRD-5 type phantoms using MCNP code, a Monte Carlo transport code. The calculations were performed for mono-energetic photon sources of twelve energies from 10 keV to 5 MeV and for phantoms of newborn, 1, 5, 10 and 15 years, and adult. Then, the effective doses to the different age-phantoms from the mono-energetic photon sources were estimated based on the obtained organ doses. The calculated effective doses were used to interpolate the conversion coefficients of the effective doses for 160 radionuclides, which are important for dose assessment of nuclear facilities. In the calculation, energies and intensities of emitted photons from radionuclides were taken from DECDC, a recent compilation of decay data for radiation dosimetry developed at JAERI. The results are tabulated in the form of effective dose per unit concentration and time (Sv per Bq s m -3 ). (author)

  19. Propagated but Topologically Distributed Forebrain Neurons Expressing Alpha-Synuclein in Aged Macaques.

    Directory of Open Access Journals (Sweden)

    Katsuo Kimura

    Full Text Available In neurodegenerative disorders, such as Parkinson's disease (PD, alpha-synuclein (α-syn accumulates to induce cell death and/or form a cytoplasmic inclusion called Lewy body (LB. This α-syn-related pathology is termed synucleinopathy. It remains unclear how α-syn accumulation expands during the progress of synucleinopathy in the human brain. In our study, we investigated the patterns of distribution and propagation of forebrain neurons expressing α-syn in aged macaques. It was found that the occurrence of α-syn-positive neurons proceeded topologically based on the midbrain dopamine pathways arising from the substantia nigra and the ventral tegmental area where they were primarily observed. In the nigrostriatal or mesolimbic dopamine pathway, the age-dependent increase in α-syn-positive neurons was evident in the striatum or the nucleus accumbens, respectively. Concerning the nigrostriatal pathway, a mediolateral or rostrocaudal gradient was seen in the substantia nigra or the striatum, respectively, and a compensatory increase in dopamine transporter occurred in the striatum regardless of the decreased dopamine level. In the mesocortical dopamine pathway, α-syn-positive neurons appeared in the prefrontal and then motor areas of the frontal lobe. Given that neither LB formation nor clinical phenotype manifestation was detected in any of the monkeys examined in the present study, aged macaques may be useful as a potential presymptomatic model for PD and LB-related neuropsychiatric disorders.

  20. Effect of bimodal harmonic structure design on the deformation behaviour and mechanical properties of Co-Cr-Mo alloy.

    Science.gov (United States)

    Vajpai, Sanjay Kumar; Sawangrat, Choncharoen; Yamaguchi, Osamu; Ciuca, Octav Paul; Ameyama, Kei

    2016-01-01

    In the present work, Co-Cr-Mo alloy compacts with a unique bimodal microstructural design, harmonic structure design, were successfully prepared via a powder metallurgy route consisting of controlled mechanical milling of pre-alloyed powders followed by spark plasma sintering. The harmonic structured Co-Cr-Mo alloy with bimodal grain size distribution exhibited relatively higher strength together with higher ductility as compared to the coarse-grained specimens. The harmonic Co-Cr-Mo alloy exhibited a very complex deformation behavior wherein it was found that the higher strength and the high retained ductility are derived from fine-grained shell and coarse-grained core regions, respectively. Finally, it was observed that the peculiar spatial/topological arrangement of stronger fine-grained and ductile coarse-grained regions in the harmonic structure promotes uniformity of strain distribution, leading to improved mechanical properties by suppressing the localized plastic deformation during straining. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. A novel and robust method for testing bimodality and characterizing porcine adipocytes of adipose tissue of 5 purebred lines of pig.

    Science.gov (United States)

    Testroet, Eric D; Sherman, Peter; Yoder, Chad; Testroet, Amber; Reynolds, Carmen; O'Neil, Mathew; Lei, Soi Meng; Beitz, Donald C; Baas, Tom J

    2017-04-03

    Adipocyte sizes from adipose tissue of mature animals form a bimodal distribution, thus reporting mean cell size is misleading. The objectives of this study were to develop a robust method for testing bimodality of porcine adipocytes, describe the size distribution with an informative metric, and statistically test hypertrophy and appearance of new small adipocytes, possibly resulting from hyperplasia or lipid filling of previously divided fibroblastic cells. Ninety-three percent of adipose samples measured were bimodal (P testing hyperplasia or lipid filling of previously divided fibroblastic cells based upon the probability of an adipocyte falling into 2 chosen competing "bins" as adiposity increases. We also conclude that increased adiposity is correlated positively with an adipocyte being found in the minor mode (r = 0.46) and correlated negatively with an adipocyte being found in the major mode (r = -0.22), providing evidence of either hyperplasia or lipid filling of previously divided fibroblastic cells. We additionally conclude that as adiposity increases, the mode of the major distribution of cells occurs at a larger diameter of adipocyte, indicating hypertrophy.

  2. The concept of the Equivalent Length of Life for quantifying differences in age-at-death distributions across countries

    NARCIS (Netherlands)

    Muszyńska, M.; Janssen, F.

    2016-01-01

    Life expectancy, that is the mean age at death in a life table, is the most common measure used to describe and compare mortality distributions. Alternatives to life expectancy that have been proposed so far have also referred to only a single parameter of the mortality distribution. We propose to

  3. Medication errors in residential aged care facilities: a distributed cognition analysis of the information exchange process.

    Science.gov (United States)

    Tariq, Amina; Georgiou, Andrew; Westbrook, Johanna

    2013-05-01

    Medication safety is a pressing concern for residential aged care facilities (RACFs). Retrospective studies in RACF settings identify inadequate communication between RACFs, doctors, hospitals and community pharmacies as the major cause of medication errors. Existing literature offers limited insight about the gaps in the existing information exchange process that may lead to medication errors. The aim of this research was to explicate the cognitive distribution that underlies RACF medication ordering and delivery to identify gaps in medication-related information exchange which lead to medication errors in RACFs. The study was undertaken in three RACFs in Sydney, Australia. Data were generated through ethnographic field work over a period of five months (May-September 2011). Triangulated analysis of data primarily focused on examining the transformation and exchange of information between different media across the process. The findings of this study highlight the extensive scope and intense nature of information exchange in RACF medication ordering and delivery. Rather than attributing error to individual care providers, the explication of distributed cognition processes enabled the identification of gaps in three information exchange dimensions which potentially contribute to the occurrence of medication errors namely: (1) design of medication charts which complicates order processing and record keeping (2) lack of coordination mechanisms between participants which results in misalignment of local practices (3) reliance on restricted communication bandwidth channels mainly telephone and fax which complicates the information processing requirements. The study demonstrates how the identification of these gaps enhances understanding of medication errors in RACFs. Application of the theoretical lens of distributed cognition can assist in enhancing our understanding of medication errors in RACFs through identification of gaps in information exchange. Understanding

  4. Bimodal atomic force microscopy imaging of isolated antibodies in air and liquids

    Energy Technology Data Exchange (ETDEWEB)

    MartInez, N F; Lozano, J R; Herruzo, E T; Garcia, F; Garcia, R [Instituto de Microelectronica de Madrid, CSIC, Isaac Newton 8, 28760 Tres Cantos, Madrid (Spain); Richter, C; Sulzbach, T [NanoWorld Services GmbH, Schottkystrasse 10, 91058 Erlangen (Germany)], E-mail: rgarcia@imm.cnm.csic.es

    2008-09-24

    We have developed a dynamic atomic force microscopy (AFM) method based on the simultaneous excitation of the first two flexural modes of the cantilever. The instrument, called a bimodal atomic force microscope, allows us to resolve the structural components of antibodies in both monomer and pentameric forms. The instrument operates in both high and low quality factor environments, i.e., air and liquids. We show that under the same experimental conditions, bimodal AFM is more sensitive to compositional changes than amplitude modulation AFM. By using theoretical and numerical methods, we study the material contrast sensitivity as well as the forces applied on the sample during bimodal AFM operation.

  5. An Eye Tracking Study on the Perception and Comprehension of Unimodal and Bimodal Linguistic Inputs by Deaf Adolescents

    Directory of Open Access Journals (Sweden)

    Eliana Mastrantuono

    2017-06-01

    Full Text Available An eye tracking experiment explored the gaze behavior of deaf individuals when perceiving language in spoken and sign language only, and in sign-supported speech (SSS. Participants were deaf (n = 25 and hearing (n = 25 Spanish adolescents. Deaf students were prelingually profoundly deaf individuals with cochlear implants (CIs used by age 5 or earlier, or prelingually profoundly deaf native signers with deaf parents. The effectiveness of SSS has rarely been tested within the same group of children for discourse-level comprehension. Here, video-recorded texts, including spatial descriptions, were alternately transmitted in spoken language, sign language and SSS. The capacity of these communicative systems to equalize comprehension in deaf participants with that of spoken language in hearing participants was tested. Within-group analyses of deaf participants tested if the bimodal linguistic input of SSS favored discourse comprehension compared to unimodal languages. Deaf participants with CIs achieved equal comprehension to hearing controls in all communicative systems while deaf native signers with no CIs achieved equal comprehension to hearing participants if tested in their native sign language. Comprehension of SSS was not increased compared to spoken language, even when spatial information was communicated. Eye movements of deaf and hearing participants were tracked and data of dwell times spent looking at the face or body area of the sign model were analyzed. Within-group analyses focused on differences between native and non-native signers. Dwell times of hearing participants were equally distributed across upper and lower areas of the face while deaf participants mainly looked at the mouth area; this could enable information to be obtained from mouthings in sign language and from lip-reading in SSS and spoken language. Few fixations were directed toward the signs, although these were more frequent when spatial language was transmitted. Both

  6. An Eye Tracking Study on the Perception and Comprehension of Unimodal and Bimodal Linguistic Inputs by Deaf Adolescents.

    Science.gov (United States)

    Mastrantuono, Eliana; Saldaña, David; Rodríguez-Ortiz, Isabel R

    2017-01-01

    An eye tracking experiment explored the gaze behavior of deaf individuals when perceiving language in spoken and sign language only, and in sign-supported speech (SSS). Participants were deaf ( n = 25) and hearing ( n = 25) Spanish adolescents. Deaf students were prelingually profoundly deaf individuals with cochlear implants (CIs) used by age 5 or earlier, or prelingually profoundly deaf native signers with deaf parents. The effectiveness of SSS has rarely been tested within the same group of children for discourse-level comprehension. Here, video-recorded texts, including spatial descriptions, were alternately transmitted in spoken language, sign language and SSS. The capacity of these communicative systems to equalize comprehension in deaf participants with that of spoken language in hearing participants was tested. Within-group analyses of deaf participants tested if the bimodal linguistic input of SSS favored discourse comprehension compared to unimodal languages. Deaf participants with CIs achieved equal comprehension to hearing controls in all communicative systems while deaf native signers with no CIs achieved equal comprehension to hearing participants if tested in their native sign language. Comprehension of SSS was not increased compared to spoken language, even when spatial information was communicated. Eye movements of deaf and hearing participants were tracked and data of dwell times spent looking at the face or body area of the sign model were analyzed. Within-group analyses focused on differences between native and non-native signers. Dwell times of hearing participants were equally distributed across upper and lower areas of the face while deaf participants mainly looked at the mouth area; this could enable information to be obtained from mouthings in sign language and from lip-reading in SSS and spoken language. Few fixations were directed toward the signs, although these were more frequent when spatial language was transmitted. Both native and

  7. Cervical HPV type-specific pre-vaccination prevalence and age distribution in Croatia.

    Science.gov (United States)

    Sabol, Ivan; Milutin Gašperov, Nina; Matovina, Mihaela; Božinović, Ksenija; Grubišić, Goran; Fistonić, Ivan; Belci, Dragan; Alemany, Laia; Džebro, Sonja; Dominis, Mara; Šekerija, Mario; Tous, Sara; de Sanjosé, Silvia; Grce, Magdalena

    2017-01-01

    The main etiological factor of precancerous lesion and invasive cervical cancer are oncogenic human papillomaviruses types (HPVs). The objective of this study was to establish the distribution of the most common HPVs in different cervical lesions and cancer prior to the implementation of organized population-based cervical screening and HPV vaccination in Croatia. In this study, 4,432 cervical specimens, collected through a 16-year period, were tested for the presence of HPV-DNA by polymerase chain reaction (PCR) with three sets of broad-spectrum primers and type-specific primers for most common low-risk (LR) types (HPV-6, 11) and the most common high-risk (HR) types (HPV-16, 18, 31, 33, 45, 52, 58). Additional 35 archival formalin-fixed, paraffin embedded tissue of cervical cancer specimens were analyzed using LiPA25 assay. The highest age-specific HPV-prevalence was in the group 18-24 years, which decreased continuously with age (Ptypes significantly increased (Ptype found with a prevalence (with or without another HPV-type) of 6.9% in normal cytology, 15.5% in atypical squamous cells of undetermined significance, 14.4% in low-grade squamous intraepithelial lesions, 33.3% in high-grade squamous intraepithelial lesions, and 60.9% in cervical cancer specimens (Ptypes among Croatian women, which will enable to predict and to monitor the impact of HPV-vaccination and to design effective screening strategies in Croatia.

  8. Cost-effective age structure and geographical distribution of boreal forest reserves.

    Science.gov (United States)

    Lundström, Johanna; Ohman, Karin; Perhans, Karin; Rönnqvist, Mikael; Gustafsson, Lena; Bugman, Harald

    2011-02-01

    1. Forest reserves are established to preserve biodiversity, and to maintain natural functions and processes. Today there is heightened focus on old-growth stages, with less attention given to early successional stages. The biodiversity potential of younger forests has been overlooked, and the cost-effectiveness of incorporating different age classes in reserve networks has not yet been studied.2. We performed a reserve selection analysis in boreal Sweden using the Swedish National Forest Inventory plots. Seventeen structural variables were used as biodiversity indicators, and the cost of protecting each plot as a reserve was assessed using the Heureka system. A goal programming approach was applied, which allowed inclusion of several objectives and avoided a situation in which common indicators affected the result more than rare ones. The model was limited either by budget or area.3. All biodiversity indicators were found in all age classes, with more than half having the highest values in ages ≥ 100 years. Several large-tree indicators and all deadwood indicators had higher values in forests 0-14 years than in forests 15-69 years.4. It was most cost-effective to protect a large proportion of young forests since they generally have a lower net present value compared to older forests, but still contain structures of importance for biodiversity. However, it was more area-effective to protect a large proportion of old forests since they have a higher biodiversity potential per area.5. The geographical distribution of reserves selected with the budget-constrained model was strongly biassed towards the north-western section of boreal Sweden, with a large proportion of young forest, whereas the area-constrained model focussed on the south-eastern section, with dominance by the oldest age class.6.Synthesis and applications. We show that young forests with large amounts of structures important to biodiversity such as dead wood and remnant trees are cheap and cost

  9. Spatial distribution of human neocortical neurons and glial cells according to sex and age measured by the saucer method

    DEFF Research Database (Denmark)

    Stark, Anette Kirstine; Petersen, A O; Gardi, Jonathan Eyal

    2007-01-01

    A new stereological probe, the saucer, was used for estimating three-dimensional (3D) spatial distributions of particles around particles. The advantages of the saucer include that the measurements and the results are in 3D and the size and design of the probe enables the investigator to sample...... primary neurons in the human neocortex (divided into frontal-, temporal-, parietal- and occipital cortex) of young and old subjects free of neurological or psychological disease to test if age and gender has any influence on the cell distribution in human neocortex. Plots of the spatial distribution...... disorders was independent of age and gender....

  10. Utterance independent bimodal emotion recognition in spontaneous communication

    Science.gov (United States)

    Tao, Jianhua; Pan, Shifeng; Yang, Minghao; Li, Ya; Mu, Kaihui; Che, Jianfeng

    2011-12-01

    Emotion expressions sometimes are mixed with the utterance expression in spontaneous face-to-face communication, which makes difficulties for emotion recognition. This article introduces the methods of reducing the utterance influences in visual parameters for the audio-visual-based emotion recognition. The audio and visual channels are first combined under a Multistream Hidden Markov Model (MHMM). Then, the utterance reduction is finished by finding the residual between the real visual parameters and the outputs of the utterance related visual parameters. This article introduces the Fused Hidden Markov Model Inversion method which is trained in the neutral expressed audio-visual corpus to solve the problem. To reduce the computing complexity the inversion model is further simplified to a Gaussian Mixture Model (GMM) mapping. Compared with traditional bimodal emotion recognition methods (e.g., SVM, CART, Boosting), the utterance reduction method can give better results of emotion recognition. The experiments also show the effectiveness of our emotion recognition system when it was used in a live environment.

  11. Plastic bimodal xylogenesis in conifers from continental Mediterranean climates.

    Science.gov (United States)

    Camarero, Jesús Julio; Olano, José Miguel; Parras, Alfonso

    2010-01-01

    *Seasonal radial-increment and xylogenesis data can help to elucidate how climate modulates wood formation in conifers. Few xylogenesis studies have assessed how plastic xylogenesis is in sympatric conifer species from continental Mediterranean areas, where low winter temperatures and summer drought constrain growth. *Here, we analysed intra-annual patterns of secondary growth in sympatric conifer species (Juniperus thurifera, Pinus halepensis and Pinus sylvestris). Two field sites (xeric and mesic) were evaluated using dendrometers, microcores and climatic data. *A bimodal pattern of xylogenesis characterized by spring and autumn precipitation and subsequent cambial reactivation was detected in J. thurifera at both study sites and in P. halepensis at the xeric site, but was absent in P. sylvestris where growth was largely controlled by day length. In the xeric site J. thurifera exhibited an increased response to water availability in autumn relative to P. halepensis and summer cambial suppression was more marked in J. thurifera than in P. halepensis. *Juniperus thurifera exhibited increased plasticity in its xylogenesis pattern compared with sympatric pines, enabling this species to occupy sites with more variable climatic conditions. The plastic xylogenesis patterns of junipers in drought-stressed areas may also provide them with a competitive advantage against co-occurring pines.

  12. Time-predictable bimodal volcanism in the Coso Range, California

    Science.gov (United States)

    Bacon, Charles R.

    1982-01-01

    The bimodal Pleistocene part of the Coso volcanic field has erupted rhyolite and basalt at constant long-term rates during the past ∼0.5 m.y. Both basalt and high-silica rhyolite were erupted in several independent, geologically brief episodes. The interval between eruptions of rhyolite was proportional to the volume of the preceding eruption. Basaltic eruptions appear to have followed a similar pattern. These time-predictable relations would be expected if (1) extensional strain accumulates in roof rocks at a constant rate, (2) the accumulated strain is relieved by near-vertical fractures, which serve as conduits for eruptions, and (3) the volume of erupted material is proportional to the sum of the conduit (dike) widths. The long-term eruption rate of rhyolite is about 5.4 km3/m.y.; that of basalt is about 2.8 km3/m.y. These rates are less than those of magma supply inferred from heat-flow and petrologic arguments by factors of between 100 and 200.

  13. SUBARU WEAK-LENSING STUDY OF A2163: BIMODAL MASS STRUCTURE

    International Nuclear Information System (INIS)

    Okabe, N.; Bourdin, H.; Mazzotta, P.; Maurogordato, S.

    2011-01-01

    We present a weak-lensing analysis of the merging cluster A2163 using Subaru/Suprime-Cam and CFHT/Mega-Cam data and discuss the dynamics of this cluster merger, based on complementary weak-lensing, X-ray, and optical spectroscopic data sets. From two-dimensional multi-component weak-lensing analysis, we reveal that the cluster mass distribution is well described by three main components including the two-component main cluster A2163-A with mass ratio 1:8, and its cluster satellite A2163-B. The bimodal mass distribution in A2163-A is similar to the galaxy density distribution, but appears as spatially segregated from the brightest X-ray emitting gas region. We discuss the possible origins of this gas-dark-matter offset and suggest the gas core of the A2163-A subcluster has been stripped away by ram pressure from its dark matter component. The survival of this gas core from the tidal forces exerted by the main cluster lets us infer a subcluster accretion with a non-zero impact parameter. Dominated by the most massive component of A2163-A, the mass distribution of A2163 is well described by a universal Navarro-Frenk-White profile as shown by a one-dimensional tangential shear analysis, while the singular-isothermal sphere profile is strongly ruled out. Comparing this cluster mass profile with profiles derived assuming intracluster medium hydrostatic equilibrium (H.E.) in two opposite regions of the cluster atmosphere has allowed us to confirm the prediction of a departure from H.E. in the eastern cluster side, presumably due to shock heating. Yielding a cluster mass estimate of M 500 = 11.18 +1.64 –1.46 × 10 14 h –1 M ☉ , our mass profile confirms the exceptionally high mass of A2163, consistent with previous analyses relying on the cluster dynamical analysis and Y X mass proxy.

  14. Distribution of peak expiratory flow variability by age, gender and smoking habits in a random population sample aged 20-70 yrs

    NARCIS (Netherlands)

    Boezen, H M; Schouten, J. P.; Postma, D S; Rijcken, B

    1994-01-01

    Peak expiratory flow (PEF) variability can be considered as an index of bronchial lability. Population studies on PEF variability are few. The purpose of the current paper is to describe the distribution of PEF variability in a random population sample of adults with a wide age range (20-70 yrs),

  15. Age

    Science.gov (United States)

    ... Resources About Policymakers Media ASA Member Toolkit Risks Age Explore this page: Age Do anesthesia risks increase ... can you reduce anesthesia risks in older patients? Age Age may bring wisdom but it also brings ...

  16. Influence of Controlled Cooling in Bimodal Scaffold Fabrication Using Polymers with Different Melting Temperatures

    OpenAIRE

    Lara-Padilla, Hernan; Mendoza-Buenrostro, Christian; Cardenas, Diego; Rodriguez-Garcia, Aida; Rodriguez, Ciro A.

    2017-01-01

    The combination of different materials and capabilities to manufacture at several scales open new possibilities in scaffold design for bone regeneration. This work is focused on bimodal scaffolds that combine polylactic acid (PLA) melt extruded strands with polycaprolactone (PCL) electrospun fibers. This type of bimodal scaffold offers better mechanical properties, compared to the use of PCL for the extruded strands, and provides potential a means for controlled drug and/or growth factor deli...

  17. The Spatial and Age Distribution of Stellar Populations in DDO 190

    Science.gov (United States)

    Aparicio, A.; Tikhonov, N.

    2000-05-01

    The spatial distribution of stellar populations, the star formation history, and other properties of the dwarf irregular (dIrr) galaxy DDO 190 have been analyzed using color-magnitude diagrams of about 3900 resolved stars and the Hα fluxes of H II regions. From the mean color index of the red giant branch (RGB), a mean metallicity [Fe/H]=-2.0 is obtained. The I magnitude of the tip of the RGB has been used to estimate the distance. DDO 190 is 2.9+/-0.2 Mpc from the Milky Way, 2.1 Mpc from the M94 group (Cn 5-1), 2.4 Mpc from the M81 group, and 2.9 Mpc from the barycenter of the Local Group, all indicating that it is an isolated field galaxy. The surface brightness distribution of the galaxy is well fitted by ellipses of ellipticity e=1-a/b=0.1 and position angle of 82°. The radial star density distribution follows an exponential law of scale length α=43.4", corresponding to 611 pc. The Holmberg semimajor axis to μB=26.5 is estimated to be rB26.5=3.0‧. Stellar populations of different ages in DDO 190 show strong spatial decoupling, the oldest population appearing much more extended than the youngest. Stars younger than 0.1 Gyr occupy only the central 40" (0.55 kpc) stars younger than a few (~4) Gyr extend out to ~80" (125 kpc), and for larger galactocentric distances, only older stars seem to be present. This behavior is found in all the dIrr galaxies for which spatially extended studies have been performed and could be related to the kinematic history of the galaxy. Based on observations made with the 2.5 m Nordic Optical Telescope operated on the island of La Palma by the Nordic Optical Telescope Scientific Association in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias.

  18. Plasma steroids, body composition, and fat distribution: effects of age, sex, and exercise training.

    Science.gov (United States)

    He, Zihong; Rankinen, Tuomo; Leon, Arthur S; Skinner, James S; Tchernof, André; Bouchard, Claude

    2018-03-05

    Plasma steroid hormone levels vary between men and women, but their associations with BMI and adiposity are controversial. Furthermore, little is known about the role of exercise programs on the relationship between steroid hormones and adiposity. This report evaluates these relationships for plasma levels of adrenal, gonadal, and conjugated steroids with body composition and fat distribution in sedentary men and women, aged 17-65 years, and their responses to an exercise program. In the sedentary state, 270 men (29% Blacks) and 304 women (34% Blacks) from the HERITAGE Family Study were available. Among them, 242 men and 238 women completed a 20-week fully standardized exercise program. Fourteen steroid hormones and SHBG concentrations were assayed in a fasted state and were compared for their associations with adiposity in men and women and in response to the exercise program. Covariates adjusted for in partial correlation analysis were age, ancestry, menopause status (women), and oral contraceptives/hormone replacement treatment status (women) at baseline, as well as baseline value of the trait for the training response. Differences among normal weight, overweight, and obese subjects were also considered. Statistical significance was set at P testosterone (TESTO) were negatively associated with fat mass and abdominal fat (P fat-free mass in men or women, but was significantly associated with % fat-free mass in men. No association was detected between baseline steroid hormone levels and changes in adiposity traits in response to 20 weeks of exercise. In men, low DHT, OHPROG, SHBG, and TESTO were associated with higher adiposity and abdominal and visceral fat. A similar adiposity profile was observed in women with low SHBG.

  19. Multiple regimes of operation in bimodal AFM: understanding the energy of cantilever eigenmodes

    Directory of Open Access Journals (Sweden)

    Daniel Kiracofe

    2013-06-01

    Full Text Available One of the key goals in atomic force microscopy (AFM imaging is to enhance material property contrast with high resolution. Bimodal AFM, where two eigenmodes are simultaneously excited, confers significant advantages over conventional single-frequency tapping mode AFM due to its ability to provide contrast between regions with different material properties under gentle imaging conditions. Bimodal AFM traditionally uses the first two eigenmodes of the AFM cantilever. In this work, the authors explore the use of higher eigenmodes in bimodal AFM (e.g., exciting the first and fourth eigenmodes. It is found that such operation leads to interesting contrast reversals compared to traditional bimodal AFM. A series of experiments and numerical simulations shows that the primary cause of the contrast reversals is not the choice of eigenmode itself (e.g., second versus fourth, but rather the relative kinetic energy between the higher eigenmode and the first eigenmode. This leads to the identification of three distinct imaging regimes in bimodal AFM. This result, which is applicable even to traditional bimodal AFM, should allow researchers to choose cantilever and operating parameters in a more rational manner in order to optimize resolution and contrast during nanoscale imaging of materials.

  20. BDVC (Bimodal Database of Violent Content): A database of violent audio and video

    Science.gov (United States)

    Rivera Martínez, Jose Luis; Mijes Cruz, Mario Humberto; Rodríguez Vázqu, Manuel Antonio; Rodríguez Espejo, Luis; Montoya Obeso, Abraham; García Vázquez, Mireya Saraí; Ramírez Acosta, Alejandro Álvaro

    2017-09-01

    Nowadays there is a trend towards the use of unimodal databases for multimedia content description, organization and retrieval applications of a single type of content like text, voice and images, instead bimodal databases allow to associate semantically two different types of content like audio-video, image-text, among others. The generation of a bimodal database of audio-video implies the creation of a connection between the multimedia content through the semantic relation that associates the actions of both types of information. This paper describes in detail the used characteristics and methodology for the creation of the bimodal database of violent content; the semantic relationship is stablished by the proposed concepts that describe the audiovisual information. The use of bimodal databases in applications related to the audiovisual content processing allows an increase in the semantic performance only and only if these applications process both type of content. This bimodal database counts with 580 audiovisual annotated segments, with a duration of 28 minutes, divided in 41 classes. Bimodal databases are a tool in the generation of applications for the semantic web.

  1. Emergent bimodality and switch induced by time delays and noises in a synthetic gene circuit

    Science.gov (United States)

    Zhang, Chun; Du, Liping; Xie, Qingshuang; Wang, Tonghuan; Zeng, Chunhua; Nie, Linru; Duan, Weilong; Jia, Zhenglin; Wang, Canjun

    2017-10-01

    Based on the kinetic model for obtaining emergent bistability proposed by Tan et al. (2009), the effects of the fluctuations of protein synthesis rate and maximum dilution rate, the cross-correlation between two noises, and the time delay and the strength of the feedback loop in the synthetic gene circuit have been investigated through theoretical analysis and numerical simulation. Our results show that: (i) the fluctuations of protein synthesis rate and maximum dilution rate enhance the emergent bimodality of the probability distribution phenomenon, while the cross-correlation between two noises(λ), the time delay(τ) and the strength of the feedback loop(K) cause it to disappear; and (ii) the mean first passage time(MFPT) as functions of the noise strengths exhibits a maximum, this maximum is called noise-delayed switching (NDS) of the high concentration state. The NDS phenomenon shows that the noise can modify the stability of a metastable system in a counterintuitive way, the system remains in the metastable state for a longer time compared to the deterministic case. And the τ and the K enhances the stability of the ON state. The physical mechanisms for the switch between the ON and OFF states can be explained from the point of view of the effective potential.

  2. Age-related environmental gradients influence invertebrate distribution in the Prince Charles Mountains, East Antarctica

    Science.gov (United States)

    White, Duanne; Clarke, Laurence; McKay, Alan; Cooper, Alan; Stevens, Mark I.

    2016-01-01

    The potential impact of environmental change on terrestrial Antarctic ecosystems can be explored by inspecting biodiversity patterns across large-scale gradients. Unfortunately, morphology-based surveys of Antarctic invertebrates are time-consuming and limited by the cryptic nature of many taxa. We used biodiversity information derived from high-throughput sequencing (HTS) to elucidate the relationship between soil properties and invertebrate biodiversity in the Prince Charles Mountains, East Antarctica. Across 136 analysed soil samples collected from Mount Menzies, Mawson Escarpment and Lake Terrasovoje, we found invertebrate distribution in the Prince Charles Mountains significantly influenced by soil salinity and/or sulfur content. Phyla Tardigrada and Arachnida occurred predominantly in low-salinity substrates with abundant nutrients, whereas Bdelloidea (Rotifera) and Chromadorea (Nematoda) were more common in highly saline substrates. A significant correlation between invertebrate occurrence, soil salinity and time since deglaciation indicates that terrain age indirectly influences Antarctic terrestrial biodiversity, with more recently deglaciated areas supporting greater diversity. Our study demonstrates the value of HTS metabarcoding to investigate environmental constraints on inconspicuous soil biodiversity across large spatial scales. PMID:28083092

  3. TracerLPM (Version 1): An Excel® workbook for interpreting groundwater age distributions from environmental tracer data

    Science.gov (United States)

    Jurgens, Bryant C.; Böhlke, J.K.; Eberts, Sandra M.

    2012-01-01

    TracerLPM is an interactive Excel® (2007 or later) workbook program for evaluating groundwater age distributions from environmental tracer data by using lumped parameter models (LPMs). Lumped parameter models are mathematical models of transport based on simplified aquifer geometry and flow configurations that account for effects of hydrodynamic dispersion or mixing within the aquifer, well bore, or discharge area. Five primary LPMs are included in the workbook: piston-flow model (PFM), exponential mixing model (EMM), exponential piston-flow model (EPM), partial exponential model (PEM), and dispersion model (DM). Binary mixing models (BMM) can be created by combining primary LPMs in various combinations. Travel time through the unsaturated zone can be included as an additional parameter. TracerLPM also allows users to enter age distributions determined from other methods, such as particle tracking results from numerical groundwater-flow models or from other LPMs not included in this program. Tracers of both young groundwater (anthropogenic atmospheric gases and isotopic substances indicating post-1940s recharge) and much older groundwater (carbon-14 and helium-4) can be interpreted simultaneously so that estimates of the groundwater age distribution for samples with a wide range of ages can be constrained. TracerLPM is organized to permit a comprehensive interpretive approach consisting of hydrogeologic conceptualization, visual examination of data and models, and best-fit parameter estimation. Groundwater age distributions can be evaluated by comparing measured and modeled tracer concentrations in two ways: (1) multiple tracers analyzed simultaneously can be evaluated against each other for concordance with modeled concentrations (tracer-tracer application) or (2) tracer time-series data can be evaluated for concordance with modeled trends (tracer-time application). Groundwater-age estimates can also be obtained for samples with a single tracer measurement at one

  4. Fighting Hepatitis B in North Korea: Feasibility of a Bi-modal Prevention Strategy.

    Science.gov (United States)

    Unnewehr, Markus; Stich, August

    2015-11-01

    In North Korea, the prevalence of hepatitis B is high due to natural factors, gaps in vaccination, and the lack of antiviral treatment. Aid projects are urgently needed, however impeded by North Korea's political and economical situation and isolation. The feasibility of a joint North Korean and German humanitarian hepatitis B prevention program was assessed. Part 1: Hepatitis B vaccination catch-up campaign. Part 2: Implementation of endoscopic ligation of esophageal varices (EVL) by trainings in Germany and North Korea. By vaccinating 7 million children between 2010 and 2012, the hepatitis B vaccination gap was closed. Coverage of 99.23% was reached. A total of 11 hepatitis B-induced liver cirrhosis patients (mean age 41.1 yr) with severe esophageal varices and previous bleedings were successfully treated by EVL without major complications. A clinical standard operating procedure, a feedback system and a follow-up plan were developed. The bi-modal preventive strategy was implemented successfully. Parts of the project can serve as an example for other low-income countries, however its general transferability is limited due to the special circumstances in North Korea.

  5. Age frequency distribution and revised stable isotope curves for New Zealand speleothems: palaeoclimatic implications

    Directory of Open Access Journals (Sweden)

    Williams Paul W.

    2010-07-01

    Full Text Available The occurrence of speleothems in New Zealand with reversed magnetism indicates that secondary calcite deposition in caves has occurred for more than 780 thousand years (ka. 394 uranium-series dates on 148 speleothems show that such deposition has taken place somewhere in the country with little interruption for more than 500 ka. A relative probability distribution of speleothem ages indicates that most growth occurred in mild, moist interglacial and interstadial intervals, a conclusion reinforced by comparing peaks and troughs in the distribution with time series curves of speleothem δ18O and δ13C values. The stable isotope time series were constructed using data from 15 speleothems from two different regions of the country. The greater the number of overlapping speleothem series (i.e. the greater the sample depth for any one region, the more confidence is justified in considering the stacked record to be representative of the region. Revising and extending earlier work, composite records are produced for central-west North Island (CWNI and north-west South Island (NWSI. Both demonstrate that over the last 15 ka the regions responded similarly to global climatic events, but that the North Island site was also influenced by the waxing and waning of regional subtropical marine influences that penetrated from the north but did not reach the higher latitudes of the South Island. Cooling marking the commencement of the last glacial maximum (LGM was evident from about 28 ka. There was a mid-LGM interstadial at 23-21.7 ka and Termination 1 occurred around 18.1 ka. The glacial-interglacial transition was marked by a series of negative excursions in δ18O that coincide with dated recessional moraines in South Island glaciers. A late glacial cooling event, the NZ Late Glacial Reversal, occurred from 13.4-11.2 ka and this was followed by an early Holocene optimum at 10.8 ka. Comparison of δ18O records from NWSI and EPICA DML ice-core shows climatic

  6. Comparative distribution of nicotinic receptor subtypes during development, adulthood and aging: an autoradiographic study in the rat brain.

    Science.gov (United States)

    Tribollet, E; Bertrand, D; Marguerat, A; Raggenbass, M

    2004-01-01

    The distribution in the rat brain of high affinity nicotinic heteromeric acetylcholine receptors and of low affinity nicotinic, alpha7-containing, homomeric receptors was studied using in vitro light microscopic autoradiography. As ligands, we used [3H]epibatidine, or [125I]epibatidine, and [125I]alpha-bungarotoxin, respectively. In adult animals, the two types of binding sites were widely distributed in many different brain structures, including the brainstem, cerebellum, mesencephalic structures, limbic system and cortex, but their anatomical distribution differed markedly. Only in rare instances could a co-localization be observed, for example in the superficial layer of the superior colliculus. In developing animals, both types of labeling were strongly expressed during embryonic and postnatal phases. Their distributions were qualitatively similar to those observed in adult animals, with a few noticeable exceptions in the cerebral cortex, hippocampus and brain stem. In aging animals, neither the distribution nor the density of nicotinic binding sites was significantly altered. Our conclusions are the following. (a) There is little overlap in the distribution of heteromeric and alpha7-containing homomeric nicotinic receptors in the rat brain. (b) The abundance of neuronal nicotinic receptors during embryonic and postnatal development suggests that they may play a role in the establishment of neuronal connectivity. (c) The expression of neuronal nicotinic receptors is unaltered in middle aged animals, suggesting that in the rat these receptors do not play any major role in aging process.

  7. Age-specific distributions from coarse-count data: An epidemiological and demographic application of a penalized composite link model

    DEFF Research Database (Denmark)

    Rizzi, Silvia

    Vital statistics are often available to health researchers on a low resolution. In mortality analysis the distribution of deaths by age is often aggregated in groups of 5 years of age with a wide open-ended interval that sums a total for persons above age 85. The data that the researcher observes...... are therefore only an aggregate of true latent values. Grouping vital statistics in relatively wide bins before making them available is due to several reasons: Protect the privacy of patients; enable a compact presentation of the data; assemble scares observations; make them comparable with other databases...... a non-parametric method is developed to efficiently estimate age-at-death distributions and mortality rates from coarsely grouped data. The approach is based on a yet unexplored statistical model, the penalized composite link model, which extends generalized linear models. Observations are treated...

  8. Distribution of respiratory viruses which cause lower respiratory tract infection in pediatric age group

    Directory of Open Access Journals (Sweden)

    Selim Dereci

    2015-07-01

    Full Text Available Objective: To determine the appropriate treatment regimen and the clinical course of the lower respiratory tract infections( RTI s and to detect the common viral causes of lower RTI s. Methods: The present study included a total of 255 pediatric patients aged less than 7 years old and admitted to the Department of Pediatrics of Rize Training and Research Hospital between January 2014 and January 2015 with clinical pre-diagnosis of lower RTI . Nasopharyngeal swab specimens collected from these patients were tested for viral pathogens by using multiplex RT- PCR kit the ResPlex II plus Panel PRE (Qiagen, Germany. Results: A total of 212 out of 255 (83.1% specimens revealed positive for one or more viral pathogens. The most common detected pathogens were respiratory syncytial virus ( RSV A/B in 110 samples (43.1%, rhinovirus in 51 samples (20.0%, adenovirus in 36 samples (14.1%, influenzae virus A in 32 samples (12.5%, and coronavirus in 24 samples (9.4%. In 76 samples (29.8%, more than one viral pathogen were detected. RSV was seen in more than 50% patients in the first 2 years. RSV was the most common pathogen in each year of the first 5 years but rhinovirus, influenza A and adenovirus were seen more than RSV after the fifth year. A total of 95.8% of the viral detections were seen between November and April without a significant peak amongst these months. The distribution of the pathogens by months of the year showed no significance. Conclusions: These findings can contribute to epidemiological data of Turkey. Detection of the viral pathogens causing lower RTIs can be critical in management of the disease, decrease inappropriate antibiotic treatment, and lower the morbidity and mortality rates in such diseases.

  9. Gradual changes in the age distribution of excess deaths in the years following the 1918 influenza pandemic in Copenhagen

    DEFF Research Database (Denmark)

    Saglanmak, Neslihan; Andreasen, Viggo; Simonsen, Lone

    2011-01-01

    Background: The 1918 influenza pandemic was associated with an unusual age pattern of mortality, with most deaths occurring among young adults. Few studies have addressed changes in the age distribution for influenza-related mortality in the pre-pandemic and post-pandemic period, which has...... implications for pandemic preparedness. In the present paper, we analyse the age patterns of influenza-related excess mortality in the decades before and after the 1918 pandemic, using detailed historic surveillance data from Copenhagen. Methods: Weekly age-specific rates of respiratory mortality and influenza...... of excess mortality rates between age groups and influenza seasons. Results: Individuals aged 15–64 years experienced sharply elevated excess respiratory mortality rates in the 1918–1919 and 1919–1920 pandemic periods, compared to pre-pandemic seasons (RR for excess mortality in the fall of 1918 = 67...

  10. Relationships between age-related changes of sex steroids, obesity and body fat distribution among healthy Polish males.

    Science.gov (United States)

    Jankowska, E A; Rogucka, E; Medraś, M; Welon, Z

    2000-01-01

    During the process of aging in males a trend toward an unfavourable body fat accumulation, especially within the visceral depots, is observed. This fact is presumed to be associated with the age-related decline in androgen levels among aging men. The aim of this study was to determine the relationships between sex steroid levels (DHEAS, estradiol, free and total testosterone) and BMI, percent fat mass, WHR values in 190 healthy and professionally active men, aged 22-67, inhabitants of the city of Wroclaw, Poland. Hormonal levels were measured using standard immunoassays. BMI was used as a measurement of obesity. Obesity was also assessed using percent fat mass equations according to the Crook formula. WHR was used as an index of fat distribution. All the correlations between sex steroids, BMI, WHR, percent fat mass and age were evaluated using statistical non-parametric analyses (Spearman coefficient) in the entire group of examined subjects, and in two age-specific groups: a) younger males (aged 22-39) and b) older males (aged 40-67). The aging of Polish males is accompanied by both a significant increase of BMI, percent fat mass and WHR values, and by a decline in estradiol, gonadal and adrenal androgen levels. In the younger group only total testosterone levels were significantly negatively related to BMI, percent fat mass and WHR. Within the group of older men both estradiol and DHEAS levels are significantly positively related to WHR. The sex steroids seem to be associated with indices of overall obesity and distribution of fat in men, but these relationships differ considerably when they are evaluated in younger and older age categories. Worthy of notice is the fact that free testosterone levels are not related to any anthropometric parameters in any age category, although free testosterone (not total testosterone) is commonly recognised as a reliable and sensitive endocrinological indicator of the general psycho-physical status of an aging man.

  11. Adiposity in aboriginal people from Arnhem Land, Australia: variation in degree and distribution associated with age, sex and lifestyle.

    Science.gov (United States)

    Jones, C O; White, N G

    1994-01-01

    A number of researchers have found substantial sex, population and group differences in adiposity and fat-distribution patterns, but there is relatively little information on body fat distribution in Aboriginal groups, especially for the indigenous people of Australia. This study, the largest of its kind for Australian Aboriginal people, presents information on adiposity and fat distribution in 425 Yolngu, a group of Aboriginal people living in a number of communities representing a wide range of lifestyles, in northeast Arnhem Land, Australia. Using BMI standards developed for people of European descent, the majority of the individuals in this study were lean, and the incidence of obesity was considerably less than in other Australian groups, Aboriginal and non-Aboriginal. For the Yolngu in this study the relationship between ageing and adiposity is similar to that reported for tradition-orientated Aboriginal people, as well as for a number of other indigenous groups, viz., while the men maintain their weight into old age, the women, once they are past early adulthood, lose body fat with age. The results from the present study suggest that the age at which the Yolngu women start to gain, and subsequently lose, body fat is associated with differences in degree of acculturation. As has been found in other populations, age- and sex-related differences in body fat distribution occur, but no correlation was found between adiposity and fat distribution. The Aboriginal women and men, however, had a significantly more central distribution of subcutaneous fat than their non-Aboriginal counterparts. Our findings have implications for the health and demography of Aboriginal people in general, and the Yolngu in particular, as they continue the transition from hunting and foraging towards a more 'westernized' lifestyle.

  12. Lanthanide oxide and phosphate nanoparticles for thermometry and bimodal imaging =

    Science.gov (United States)

    Debasu, Mengistie Leweyehu

    . Finalmente, estudam-se as propriedades de fotoluminescencia correspondentes as conversoes ascendente e descendente de energia em nanocristais de (Gd,Yb,Tb)PO4 sintetizados por via hidrotermica. A relaxividade (ressonancia magnetica) do 1H destes materiais sao investigadas, tendo em vista possiveis aplicacoes em imagem bimodal (luminescencia e ressonancia magnetica nuclear).

  13. Distribution of Estimated Stand Age Across Siberian Larch Forests, 1989-2012

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides mapped estimates of the stand age of young (less than 25 years old) larch forests across Siberia from 1989-2012 at 30-m resolution. The age...

  14. Aging-related alterations in the distribution of Ca2+-dependent PKC isoforms in rabbit hippocampus

    NARCIS (Netherlands)

    Van der Zee, EA; Palm, IF; O'Connor, M; Maizels, ET; Hunzicker-Dunn, M; Disterhoft, J; O’Connor, M.; Palm, L.F.

    2004-01-01

    The immunocytochemical and subcellular localization of the Ca2+-dependent protein kinase C (cPKC) isoforms (PKCalpha, beta1, beta2, and gamma) was examined in rabbit hippocampus of young (3 months of age; n = 11) and aging (36 months of age; n = 14) subjects. Detailed immunocytochemical analyses

  15. Parental smoking during pregnancy and total and abdominal fat distribution in school-age children: The Generation R Study

    NARCIS (Netherlands)

    B. Durmus (Busra); D.H.M. Heppe (Denise); H.R. Taal (Rob); R. Manniesing (Rashindra); H. Raat (Hein); A. Hofman (Albert); E.A.P. Steegers (Eric); R. Gaillard (Romy); V.W.V. Jaddoe (Vincent)

    2014-01-01

    textabstractObjective: Fetal smoke exposure may influence growth and body composition later in life. We examined the associations of maternal and paternal smoking during pregnancy with total and abdominal fat distribution in school-age children. Methods: We performed a population-based prospective

  16. [Gaussian distribution of intelligence in VLBW preterm infants at age 5: very low correlation with very low birth weight].

    Science.gov (United States)

    van Baalen, A; Ross, C; Kewitz, G; Mildenberger, E; Berns, M; Bartsch, M; Kössel, H; Kruppa, E; Bohn, R; Versmold, H

    2008-04-01

    Preterm infants with very low birth weight intelligence values, we studied the distribution of intelligence at preschool age in VLBW infants and the risk factors influencing this distribution. A prospective cohort study of 277 VLBW infants intelligence (Kaufman-Assessment Battery for Children) at age 5. Statistical methods employed were: explorative data analysis, correlation, chi (2)- and t-tests; the tested variables were: small for gestational age ( 0.21 > or = 36 weeks), intraventricular hemorrhage, ventricular dilation, periventricular leukomalacia, seizures, abnormal acoustic evoked potentials, and hyperexcitability at discharge. The distribution of intelligence in 137 VLBW infants intelligence increased very slightly with birth weight (Pearson correlation: 0.172; p = 0.045) and was significantly lower in children with hypoglycemia after the first day of life (- 13.35; 95 % confidence interval: - 20.08 to - 6.63; p = 0.002), hyperexcitability at discharge (- 16.28; 95 % confidence interval: - 25.26 to - 7.31; p = 0.005), and bronchopulmonary dysplasia (- 7.00; 95 % confidence interval - 11.71 to - 2.29; p = 0.039). At preschool age, the intelligence of VLBW infants is normally distributed and correlates only slightly with the very low birth weight. Hypoglycemia after the first day of life and bronchopulmonary dysplasia are risk factors for lower intelligence. Hyperexcitability at discharge seemed to represent a promising prognostic factor for a later intelligence reduction.

  17. Rotated sigmoid structures in managed uneven-aged northern hardwood stands: a look at the Burr Type III distribution

    Science.gov (United States)

    Jeffrey H. Gove; Mark J. Ducey; William B. Leak; Lianjun Zhang

    2008-01-01

    Stand structures from a combined density manipulation and even- to uneven-aged conversion experiment on the Bartlett Experimental Forest (New Hampshire, USA) were examined 25 years after initial treatment for rotated sigmoidal diameter distributions. A comparison was made on these stands between two probability density functions for fitting these residual structures:...

  18. The changes of stage distribution of seminiferous epithelium cycle and its correlations with Leydig cell stereological parameters in aging men.

    Science.gov (United States)

    Huang, Rui; Zhu, Wei-Jie; Li, Jing; Gu, Yi-Qun

    2014-12-01

    To evaluate the changes of stage distribution of seminiferous epithelium cycle and its correlations with Leydig cell stereological parameters in aging men. Point counting method was used to analyze the stereological parameters of Leydig cells. The stage number of seminiferous epithelium cycle was calculated in the same testicular tissue samples which were used for Leydig cell stereological analysis. The aging group had shown more severe pathological changes as well as higher pathologic scores than the young group. Compared with the control group, the volume density (VV) and surface density (NA) of Leydig cells in the aging group were increased significantly. The stage number of seminiferous epithelium cycle in the aging group was decreased coincidently compared to the young group. Leydig cell Vv in the young group has a positive relationship with stages I, II, III, V and VI of seminiferous epithelium cycle, and Leydig cell NA and numerical density (NV) were positively related to stage IV. However, only the correlation between NV and stage II was found in the aging group. The stage number of seminiferous epithelium cycle was decreased in aging testes. Changes in the stage distribution in aging testes were related to the Leydig cell stereological parameters which presented as a sign of morphological changes. Copyright © 2014 Elsevier GmbH. All rights reserved.

  19. A demographic study of the exponential distribution applied to uneven-aged forests

    Science.gov (United States)

    Jeffrey H. Gove

    2016-01-01

    A demographic approach based on a size-structured version of the McKendrick-Von Foerster equation is used to demonstrate a theoretical link between the population size distribution and the underlying vital rates (recruitment, mortality and diameter growth) for the population of individuals whose diameter distribution is negative exponential. This model supports the...

  20. Auditory-somatosensory bimodal stimulation desynchronizes brain circuitry to reduce tinnitus in guinea pigs and humans.

    Science.gov (United States)

    Marks, Kendra L; Martel, David T; Wu, Calvin; Basura, Gregory J; Roberts, Larry E; Schvartz-Leyzac, Kara C; Shore, Susan E

    2018-01-03

    The dorsal cochlear nucleus is the first site of multisensory convergence in mammalian auditory pathways. Principal output neurons, the fusiform cells, integrate auditory nerve inputs from the cochlea with somatosensory inputs from the head and neck. In previous work, we developed a guinea pig model of tinnitus induced by noise exposure and showed that the fusiform cells in these animals exhibited increased spontaneous activity and cross-unit synchrony, which are physiological correlates of tinnitus. We delivered repeated bimodal auditory-somatosensory stimulation to the dorsal cochlear nucleus of guinea pigs with tinnitus, choosing a stimulus interval known to induce long-term depression (LTD). Twenty minutes per day of LTD-inducing bimodal (but not unimodal) stimulation reduced physiological and behavioral evidence of tinnitus in the guinea pigs after 25 days. Next, we applied the same bimodal treatment to 20 human subjects with tinnitus using a double-blinded, sham-controlled, crossover study. Twenty-eight days of LTD-inducing bimodal stimulation reduced tinnitus loudness and intrusiveness. Unimodal auditory stimulation did not deliver either benefit. Bimodal auditory-somatosensory stimulation that induces LTD in the dorsal cochlear nucleus may hold promise for suppressing chronic tinnitus, which reduces quality of life for millions of tinnitus sufferers worldwide. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  1. Ice age distriutions of European small mammals: insights from species distribution modelling

    DEFF Research Database (Denmark)

    Fløjgaard, Camilla; Normand, Signe; Skov, Flemming

    2009-01-01

    that areas with a suitable LGM climate for the three temperate species (Apodemus flavicollis, Apodemus sylvaticus and Microtus arvalis) were largely restricted to the traditionally recognized southern refuge areas, i.e. mainly in the Mediterranean region, but also southernmost France and southern parts...... evidence. Our aim was to investigate the potential refuge locations using species distribution modelling to estimate the geographical distribution of suitable climatic conditions for selected rodent species during the LGM. Location Eurasia. Methods Presence/absence data for seven rodent species with range...... predictors of the species distributions across Siberia were projected onto LGM climate simulations to assess the distribution of climatically suitable areas. Results.The best distribution models provided good predictions of the present-day Siberian ranges of the study species. Their LGM projections showed...

  2. Age-dependent trigeminal and female-specific lumbosacral increase in herpes zoster distribution in the elderly.

    Science.gov (United States)

    Shiraki, Kimiyasu; Toyama, Nozomu; Shiraki, Atsuko; Yajima, Misako

    2018-01-31

    Varicella-zoster virus causes herpes zoster (HZ) along specific dermatomes, but the effects of age and sex on HZ distribution are unclear. We investigated the age- and sex-dependent distribution characteristics of HZ. Patients with HZ were monitored by members of the Miyazaki Dermatologist Society. Questionnaires containing information on age, sex, and dermatome distribution and lesion specimens from 2730 patients were collected, and 2508 PCR-diagnosed cases were analyzed. The ratio of lesions in the thoracic area to lesions in the whole body decreased with age, whereas those of other areas increased. HZ incidence increased with age to about four times that of the basic incidence in the dermatome areas at age 0-29 years; the incidence in the trigeminal area in both sexes increased 11-fold, and the incidence in the thoracic and lumbosacral areas increased in females more than in males. Furthermore, the fact that the highest incidence was found along the first branch of the trigeminal nerve suggests an association with long-term ultraviolet ray exposure. Segmental dermatomes comprising thoracic 10-lumbar 1/sacral 2-4 and thoracic 5-6 were significantly more frequently affected in female patients at age 50-59 years and are consistent with areas of obstetric anesthesia for childbirth and of breastfeeding, respectively. HZ incidence increased with age; moreover, exposure to ultraviolet rays, childbirth, and breastfeeding might increase the incidence at specific dermatomes in older individuals. This study provides important information on the etiology of HZ. Copyright © 2018 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.

  3. Age and transit time distributions of carbon in a nonlinear global model perturbed by nonautonomous fossil-fuel emissions signals

    Science.gov (United States)

    Metzler, Holger; Müller, Markus; Sierra, Carlos A.

    2017-04-01

    Carbon fluxes in the ocean-atmosphere-biosphere system are governed by nonlinear processes, which are usually modeled by a system of ordinary differential equations. It is very difficult to analyze such nonlinear models and to predict their future behavior, particularly their internal age structure: How old is the carbon in different pools (ages) and how old is the carbon that leaves the system (transit times)? How is this age structure modified by the addition of fossil fuel emissions? To answer these questions, we developed a new mathematical approach that allows us to compute and visualize the age structure of models of well mixed pools even if they are nonlinear and nonautonomous. We do not only consider mean ages and mean transit times, but entire distributions. Consequently, we can consider important statistics such as the median, quantiles, or the variance. We applied this mathematical approach to a nonlinear global carbon model consisting of three pools (atmosphere, surface ocean, and terrestrial biosphere) and driven by four emission scenarios (RCP3-PD, RCP4.5, RCP6, RCP8.5). Results showed that the addition of fossil fuels modifies the age structure of C in the atmosphere by drastically increasing its proportion of young carbon. We found little differences among predicted mean ages for the four emission scenarios, but changes in the overall distributions were large with effects on median, quantiles and variance. In the short-term, fossil-fuel emissions have an important effect on the amount of carbon that is exchanged among Earth's main C reservoirs. In the long-term, most added C will eventually end up in the deep ocean, but the time required to return to pre-industrial C age distributions is largely dependent on emission scenarios.

  4. Effects of aging on the cerebral distribution of technetium-99m hexamethylpropylene amine oxime in healthy humans.

    Science.gov (United States)

    Mozley, P D; Sadek, A M; Alavi, A; Gur, R C; Muenz, L R; Bunow, B J; Kim, H J; Stecker, M H; Jolles, P; Newberg, A

    1997-07-01

    Some brain functions decline at a linear rate throughout adulthood. Others remain relatively stable until very late in the life cycle. This study characterized the effects of aging on the regional cerebral distribution of hexamethylpropylene amine oxime (HMPAO) in healthy human volunteers. The sample consisted of 26 men and 18 women with a mean age of 41.6+/-14.9 years (range: 19-73). Their past medical histories, physical examinations, and laboratory screening tests were normal. Single-photon emission tomography (SPET) scans of the brain were performed with a standardized acquisition and processing protocol on a triple-headed camera equipped with fan beam collimators. A 3-D restorative filter and a correction for uniform attenuation were applied before the images were reinterpolated in planes parallel to the line connecting the frontal and occipital poles. Mean counts per pixel were measured in multiple regions of interest (ROIs) within each hemisphere by custom fitting a set of templates to the images. The mean activity in each ROI was compared with the mean activity per pixel in the whole brain. Regression analyses were used to relate the activity ratios to age with both linear and nonlinear models. The relative concentration of radioactivity decreased significantly with age in most, but not all, gray matter structures. It increased in the white matter regions. The nonlinear model of aging fit the data significantly better than a straight line did. Most of the changes with age occurred during young adulthood. No further changes were detectable after the onset of middle age. The median breakpoint age at which the rate of change became negligible was 36.6 years. Aging significantly affects the relative uptake of HMPAO in healthy humans. It decreases in many gray matter regions and increases in most white matter regions. However, the changes do not appear to be linear. Most seem to occur during young adulthood before people reach their late thirties. The

  5. Changes in Angiotensin Receptor Distribution and in Aortic Morphology Are Associated with Blood Pressure Control in Aged Metabolic Syndrome Rats

    Directory of Open Access Journals (Sweden)

    Verónica Guarner-Lans

    2016-01-01

    Full Text Available The role of the renin-angiotensin system (RAS in blood pressure regulation in MS during aging is unknown. It participates in metabolic syndrome (MS and aging regulating vascular tone and remodeling. RAS might participate in a compensatory mechanism decreasing blood pressure and allowing MS rats to reach 18 months of age and it might form part of therapeutical procedures to ameliorate MS. We studied histological changes and distribution of RAS receptors in aortas of MS aged rats. Electron microscopy images showed premature aging in MS since the increased fibrosis, enlarged endothelium, and invasion of this layer by muscle cells that was present in control 18-month-old aortas were also found in 6-month-old aortas from MS rats. AT1, AT2, and Mas receptors mediate the effects of Ang II and Ang 1-7, respectively. Fluorescence from AT2 decreased with age in control and MS aortas, while fluorescence of AT1 increased in aortas from MS rats at 6 months and diminished during aging. Mas expression increased in MS rats and remained unchanged in control rats. In conclusion, there is premature aging in the aortas from MS rats and the elevated expression of Mas receptor might contribute to decrease blood pressure during aging in MS.

  6. What can flux tracking teach us about water age distribution patterns and their temporal dynamics?

    NARCIS (Netherlands)

    Hrachowitz, M.; Savenije, H.; Bogaard, T.A.; Tetzlaff, D.; Soulsby, C.

    2013-01-01

    The complex interactions of runoff generation processes underlying the hydrological response of streams remain not entirely understood at the catchment scale. Extensive research has demonstrated the utility of tracers for both inferring flow path distributions and constraining model

  7. Application of a bi-modal PBR nuclear propulsion and power system to military missions

    Science.gov (United States)

    Venetoklis, Peter S.

    1995-01-01

    The rapid proliferation of arms technology and space access combined with current economic realities in the United States are creating ever greater demands for more capable space-based military assets. The paper illustrates that bi-modal nuclear propulsion and power based on the Particle Bed Reactor (PBR) is a high-leverage tehcnology that can maximize utility while minimizing cost. Mission benefits offered by the bi-modal PBR, including enhanced maneuverability, lifetime, survivability, payload power, and operational flexibility, are discussed. The ability to deliver desired payloads on smaller boosters is also illustrated. System descriptions and parameters for 10 kWe and 100 kWe power output levels are summarized. It is demonstrated via design exercise that bi-modal PBR dramtically enhances performance of a military satellite in geosynchronous orbit, increasing payload mass, payload power, and maneuverability.

  8. A bimodal power and propulsion system based on cermet fuel and heat pipe energy transport

    International Nuclear Information System (INIS)

    Polansky, G.F.; Gunther, N.A.; Rochow, R.F.; Bixler, C.H.

    1995-01-01

    Bimodal space reactor systems provide both thermal propulsion for the spacecraft orbital transfer and electrical power to the spacecraft bus once it is on station. These systems have the potential to increase both the available payload in high energy orbits and the available power to that payload. These increased mass and power capabilities can be used to either reduce mission cost by permitting the use of smaller launch vehicles or to provide increased mission performance from the current launch vehicle. A major barrier to the deployment of these bimodal systems has been the cost associated with their development. This paper describes a bimodal reactor system with performance potential to permit more than 70% of the instrumented payload of the Titan IV/Centaur to be launched from the Atlas IIAS. The development cost is minimized by basing the design on existing component technologies

  9. Evaluating visibility of age spot and freckle based on simulated spectral reflectance distribution and facial color image

    Science.gov (United States)

    Hirose, Misa; Toyota, Saori; Tsumura, Norimichi

    2018-02-01

    In this research, we evaluate the visibility of age spot and freckle with changing the blood volume based on simulated spectral reflectance distribution and the actual facial color images, and compare these results. First, we generate three types of spatial distribution of age spot and freckle in patch-like images based on the simulated spectral reflectance. The spectral reflectance is simulated using Monte Carlo simulation of light transport in multi-layered tissue. Next, we reconstruct the facial color image with changing the blood volume. We acquire the concentration distribution of melanin, hemoglobin and shading components by applying the independent component analysis on a facial color image. We reproduce images using the obtained melanin and shading concentration and the changed hemoglobin concentration. Finally, we evaluate the visibility of pigmentations using simulated spectral reflectance distribution and facial color images. In the result of simulated spectral reflectance distribution, we found that the visibility became lower as the blood volume increases. However, we can see that a specific blood volume reduces the visibility of the actual pigmentations from the result of the facial color images.

  10. The Distribution of Pubertal Age among Male School Students in Jatinangor District from April to June 2013

    Directory of Open Access Journals (Sweden)

    Karthik Yogaswaran

    2016-03-01

    Full Text Available Background: Puberty is important and exciting lifetime changes in an individual. Many new changes are experienced during puberty, such as physically, mentally, and emotionally. Currently, young males worldwide have different onset of pubertal age. Many factors may result in this change of pubertal age. The exact pubertal age was still unknown due to less study conducted previously. Therefore, the aim of this study was to identify the distribution of pubertal age among male school students in Jatinangor. Methods: A descriptive study was conducted from April to June 2013. A secondary data were obtained from the Jatinangor Cohort Study, from the Department of Epidemiology and Biostatistics, Faculty of Medicine, Universitas Padjadjaran. The samples were taken via cluster random sampling from 48 schools around Jatinangor. Randomization was conducted and a total of 219 male students were finally obtained from the overall data which had at least single onset of pubertal changes. This presents a response rate of 82.33%. Results: The earliest onset of pubertal age was identified as 9 years old and the oldest onset was 18 years old. The majority onset of pubertal age ranged from 12 to 15 years old with average mean of 13 years. Voice changes were identified as the early sign of puberty among males. Conclusions: Majority of the students undergo puberty at age 13 which is earlier compared to previous studies. Thus, this study indicates decreasing in onset of pubertal age among male school students in Jatinangor.

  11. Influenza mortality in the United States, 2009 pandemic: burden, timing and age distribution.

    Directory of Open Access Journals (Sweden)

    Ann M Nguyen

    Full Text Available BACKGROUND: In April 2009, the most recent pandemic of influenza A began. We present the first estimates of pandemic mortality based on the newly-released final data on deaths in 2009 and 2010 in the United States. METHODS: We obtained data on influenza and pneumonia deaths from the National Center for Health Statistics (NCHS. Age- and sex-specific death rates, and age-standardized death rates, were calculated. Using negative binomial Serfling-type methods, excess mortality was calculated separately by sex and age groups. RESULTS: In many age groups, observed pneumonia and influenza cause-specific mortality rates in October and November 2009 broke month-specific records since 1959 when the current series of detailed US mortality data began. Compared to the typical pattern of seasonal flu deaths, the 2009 pandemic age-specific mortality, as well as influenza-attributable (excess mortality, skewed much younger. We estimate 2,634 excess pneumonia and influenza deaths in 2009-10; the excess death rate in 2009 was 0.79 per 100,000. CONCLUSIONS: Pandemic influenza mortality skews younger than seasonal influenza. This can be explained by a protective effect due to antigenic cycling. When older cohorts have been previously exposed to a similar antigen, immune memory results in lower death rates at older ages. Age-targeted vaccination of younger people should be considered in future pandemics.

  12. Impact of Tile Drainage on the Distribution of Concentration and Age of Inorganic Soil Nitrogen.

    Science.gov (United States)

    Woo, D.; Kumar, P.

    2017-12-01

    Extensive network of tile drainage network across the Midwestern United States, northern Europe and other regions of the world have enhanced agricultural productivity. Because of its impact on sub-surface flow patterns and moisture and temperature dynamics, it controls the nitrogen cycle in agricultural systems, and its influence on nitrogen dynamics plays a key role in determining the short- and long-term evolution of soil inorganic nitrogen concentration and age. The spatial mapping of nitrogen concentration and age under tile-drained fields has, therefore, the potential to open up novel solution to the vexing challenge of reducing environmental impacts while at the same time maintaining agricultural productivity. The objective of this study is to explore the impacts of tile drains on the age dynamics of nitrate, immobile ammonium, mobile ammonia/um, and non-reactive tracer (such as chloride) by implementing two mobile interacting pore domains to capture matrix and preferential flow paths in a coupled ecohydrology and biogeochemistry model, Dhara. We applied this model to an agricultural farm supporting a corn-soybean rotation in the Midwestern United States. It should be expected that the installation of tile drains decrease the age of soil nutrient due to nutrient losses through tile drainage. However, an increase in the age of mobile ammonia/um is observed in contrast to the cases for nitrate, immobile ammonium, and non-reactive tracer. These results arise because the depletion of mobile ammonia/um due to tile drainage causes a high mobility flux from immobile ammonium to mobile ammonia/um, which also carries a considerable amount of relatively old age of immobile ammonium to mobile ammonia/um. In addition, the ages of nitrate and mobile ammonia/um in tile drainage range from 1 to 3 years, and less than a year, respectively, implying that not considering age transformations between nitrogen species would result in substantial underestimation of nitrogen ages

  13. Lipid-laden cells differentially distributed in the aging brain are functionally active and correspond to distinct phenotypes.

    Science.gov (United States)

    Shimabukuro, Marilia Kimie; Langhi, Larissa Gutman Paranhos; Cordeiro, Ingrid; Brito, José M; Batista, Claudia Maria de Castro; Mattson, Mark P; Mello Coelho, Valeria de

    2016-03-31

    We characterized cerebral Oil Red O-positive lipid-laden cells (LLC) of aging mice evaluating their distribution, morphology, density, functional activities and inflammatory phenotype. We identified LLC in meningeal, cortical and neurogenic brain regions. The density of cerebral LLC increased with age. LLC presenting small lipid droplets were visualized adjacent to blood vessels or deeper in the brain cortical and striatal parenchyma of aging mice. LLC with larger droplets were asymmetrically distributed in the cerebral ventricle walls, mainly located in the lateral wall. We also found that LLC in the subventricular region co-expressed beclin-1 or LC3, markers for autophagosome or autophagolysosome formation, and perilipin (PLIN), a lipid droplet-associated protein, suggesting lipophagic activity. Some cerebral LLC exhibited β galactosidase activity indicating a senescence phenotype. Moreover, we detected production of the pro-inflammatory cytokine TNF-α in cortical PLIN(+) LLC. Some cortical NeuN(+) neurons, GFAP(+) glia limitans astrocytes, Iba-1(+) microglia and S100β(+) ependymal cells expressed PLIN in the aging brain. Our findings suggest that cerebral LLC exhibit distinct cellular phenotypes and may participate in the age-associated neuroinflammatory processes.

  14. Lipid-laden cells differentially distributed in the aging brain are functionally active and correspond to distinct phenotypes

    Science.gov (United States)

    Shimabukuro, Marilia Kimie; Langhi, Larissa Gutman Paranhos; Cordeiro, Ingrid; Brito, José M.; Batista, Claudia Maria de Castro; Mattson, Mark P.; de Mello Coelho, Valeria

    2016-01-01

    We characterized cerebral Oil Red O-positive lipid-laden cells (LLC) of aging mice evaluating their distribution, morphology, density, functional activities and inflammatory phenotype. We identified LLC in meningeal, cortical and neurogenic brain regions. The density of cerebral LLC increased with age. LLC presenting small lipid droplets were visualized adjacent to blood vessels or deeper in the brain cortical and striatal parenchyma of aging mice. LLC with larger droplets were asymmetrically distributed in the cerebral ventricle walls, mainly located in the lateral wall. We also found that LLC in the subventricular region co-expressed beclin-1 or LC3, markers for autophagosome or autophagolysosome formation, and perilipin (PLIN), a lipid droplet-associated protein, suggesting lipophagic activity. Some cerebral LLC exhibited β galactosidase activity indicating a senescence phenotype. Moreover, we detected production of the pro-inflammatory cytokine TNF-α in cortical PLIN+ LLC. Some cortical NeuN+ neurons, GFAP+ glia limitans astrocytes, Iba-1+ microglia and S100β+ ependymal cells expressed PLIN in the aging brain. Our findings suggest that cerebral LLC exhibit distinct cellular phenotypes and may participate in the age-associated neuroinflammatory processes. PMID:27029648

  15. Greater screen time is associated with adolescent obesity: a longitudinal study of the BMI distribution from Ages 14 to 18.

    Science.gov (United States)

    Mitchell, Jonathan A; Rodriguez, Daniel; Schmitz, Kathryn H; Audrain-McGovern, Janet

    2013-03-01

    Previous research has examined the association between screen time and average changes in adolescent body mass index (BMI). Until now, no study has evaluated the longitudinal relationship between screen time and changes in the BMI distribution across mid to late adolescence. Participants (n = 1,336) were adolescents who were followed from age 14 to age 18 and surveyed every 6 months. Time spent watching television/videos and playing video games was self-reported (obese adolescents, could contribute to reducing the prevalence of adolescent obesity. Copyright © 2013 The Obesity Society.

  16. The age distribution of mortality due to influenza: pandemic and peri-pandemic

    Directory of Open Access Journals (Sweden)

    Reichert Tom

    2012-12-01

    Full Text Available Abstract Background Pandemic influenza is said to 'shift mortality' to younger age groups; but also to spare a subpopulation of the elderly population. Does one of these effects dominate? Might this have important ramifications? Methods We estimated age-specific excess mortality rates for all-years for which data were available in the 20th century for Australia, Canada, France, Japan, the UK, and the USA for people older than 44 years of age. We modeled variation with age, and standardized estimates to allow direct comparison across age groups and countries. Attack rate data for four pandemics were assembled. Results For nearly all seasons, an exponential model characterized mortality data extremely well. For seasons of emergence and a variable number of seasons following, however, a subpopulation above a threshold age invariably enjoyed reduced mortality. 'Immune escape', a stepwise increase in mortality among the oldest elderly, was observed a number of seasons after both the A(H2N2 and A(H3N2 pandemics. The number of seasons from emergence to escape varied by country. For the latter pandemic, mortality rates in four countries increased for younger age groups but only in the season following that of emergence. Adaptation to both emergent viruses was apparent as a progressive decrease in mortality rates, which, with two exceptions, was seen only in younger age groups. Pandemic attack rate variation with age was estimated to be similar across four pandemics with very different mortality impact. Conclusions In all influenza pandemics of the 20th century, emergent viruses resembled those that had circulated previously within the lifespan of then-living people. Such individuals were relatively immune to the emergent strain, but this immunity waned with mutation of the emergent virus. An immune subpopulation complicates and may invalidate vaccine trials. Pandemic influenza does not 'shift' mortality to younger age groups; rather, the mortality level

  17. The age distribution of mortality due to influenza: pandemic and peri-pandemic.

    Science.gov (United States)

    Reichert, Tom; Chowell, Gerardo; McCullers, Jonathan A

    2012-12-12

    Pandemic influenza is said to 'shift mortality' to younger age groups; but also to spare a subpopulation of the elderly population. Does one of these effects dominate? Might this have important ramifications? We estimated age-specific excess mortality rates for all-years for which data were available in the 20th century for Australia, Canada, France, Japan, the UK, and the USA for people older than 44 years of age. We modeled variation with age, and standardized estimates to allow direct comparison across age groups and countries. Attack rate data for four pandemics were assembled. For nearly all seasons, an exponential model characterized mortality data extremely well. For seasons of emergence and a variable number of seasons following, however, a subpopulation above a threshold age invariably enjoyed reduced mortality. 'Immune escape', a stepwise increase in mortality among the oldest elderly, was observed a number of seasons after both the A(H2N2) and A(H3N2) pandemics. The number of seasons from emergence to escape varied by country. For the latter pandemic, mortality rates in four countries increased for younger age groups but only in the season following that of emergence. Adaptation to both emergent viruses was apparent as a progressive decrease in mortality rates, which, with two exceptions, was seen only in younger age groups. Pandemic attack rate variation with age was estimated to be similar across four pandemics with very different mortality impact. In all influenza pandemics of the 20th century, emergent viruses resembled those that had circulated previously within the lifespan of then-living people. Such individuals were relatively immune to the emergent strain, but this immunity waned with mutation of the emergent virus. An immune subpopulation complicates and may invalidate vaccine trials. Pandemic influenza does not 'shift' mortality to younger age groups; rather, the mortality level is reset by the virulence of the emerging virus and is moderated

  18. The age distribution of mortality due to influenza: pandemic and peri-pandemic

    Science.gov (United States)

    2012-01-01

    Background Pandemic influenza is said to 'shift mortality' to younger age groups; but also to spare a subpopulation of the elderly population. Does one of these effects dominate? Might this have important ramifications? Methods We estimated age-specific excess mortality rates for all-years for which data were available in the 20th century for Australia, Canada, France, Japan, the UK, and the USA for people older than 44 years of age. We modeled variation with age, and standardized estimates to allow direct comparison across age groups and countries. Attack rate data for four pandemics were assembled. Results For nearly all seasons, an exponential model characterized mortality data extremely well. For seasons of emergence and a variable number of seasons following, however, a subpopulation above a threshold age invariably enjoyed reduced mortality. 'Immune escape', a stepwise increase in mortality among the oldest elderly, was observed a number of seasons after both the A(H2N2) and A(H3N2) pandemics. The number of seasons from emergence to escape varied by country. For the latter pandemic, mortality rates in four countries increased for younger age groups but only in the season following that of emergence. Adaptation to both emergent viruses was apparent as a progressive decrease in mortality rates, which, with two exceptions, was seen only in younger age groups. Pandemic attack rate variation with age was estimated to be similar across four pandemics with very different mortality impact. Conclusions In all influenza pandemics of the 20th century, emergent viruses resembled those that had circulated previously within the lifespan of then-living people. Such individuals were relatively immune to the emergent strain, but this immunity waned with mutation of the emergent virus. An immune subpopulation complicates and may invalidate vaccine trials. Pandemic influenza does not 'shift' mortality to younger age groups; rather, the mortality level is reset by the virulence

  19. Modeling violations of the race model inequality in bimodal paradigms: co-activation from decision and non-decision components

    Directory of Open Access Journals (Sweden)

    Michael eZehetleitner

    2015-03-01

    Full Text Available The redundant-signals paradigm (RSP is designed to investigate response behavior in perceptual tasks in which response-relevant targets are defined by either one or two features, or modalities. The common finding is that responses are speeded for redundantly compared to singly defined targets. This redundant-signals effect (RSE can be accounted for by race models if the response times do not violate the race model inequality (RMI. When there are violations of the RMI, race models are effectively excluded as a viable account of the RSE. The common alternative is provided by co-activation accounts, which assume that redundant target signals are integrated at some processing stage. However, ‘co-activation’ has mostly been only indirectly inferred and the accounts have only rarely been explicitly modeled; if they were modeled, the RSE has typically been assumed to have a decisional locus. Yet, there are also indications in the literature that the RSE might originate, at least in part, at a non-decisional or motor stage. In the present study, using a distribution analysis of sequential-sampling models (ex-Wald and Ratcliff Diffusion model, the locus of the RSE was investigated for two bimodal (audio-visual detection tasks that strongly violated the RMI, indicative of substantial co-activation. Three model variants assuming different loci of the RSE were fitted to the quantile reaction time proportions: a decision, a non-decision, and a combined variant both to vincentized group as well as individual data. The results suggest that for the two bimodal detection tasks, co-activation has a shared decisional and non-decisional locus. These findings point to the possibility that the mechanisms underlying the RSE depend on the specifics (task, stimulus, conditions, etc. of the experimental paradigm.

  20. SDSS-IV MaNGA: Stellar angular momentum of about 2300 galaxies: unveiling the bimodality of massive galaxy properties

    Science.gov (United States)

    Graham, Mark T.; Cappellari, Michele; Li, Hongyu; Mao, Shude; Bershady, Matthew; Bizyaev, Dmitry; Brinkmann, Jonathan; Brownstein, Joel R.; Bundy, Kevin; Drory, Niv; Law, David R.; Pan, Kaike; Thomas, Daniel; Wake, David A.; Weijmans, Anne-Marie; Westfall, Kyle B.; Yan, Renbin

    2018-03-01

    We measure λ _{R_e}, a proxy for galaxy specific stellar angular momentum within one effective radius, and the ellipticity, ɛ, for about 2300 galaxies of all morphological types observed with integral field spectroscopy as part of the MaNGA survey, the largest such sample to date. We use the (λ _{R_e}, ɛ ) diagram to separate early-type galaxies into fast and slow rotators. We also visually classify each galaxy according to its optical morphology and two-dimensional stellar velocity field. Comparing these classifications to quantitative λ _{R_e} measurements reveals tight relationships between angular momentum and galaxy structure. In order to account for atmospheric seeing, we use realistic models of galaxy kinematics to derive a general approximate analytic correction for λ _{R_e}. Thanks to the size of the sample and the large number of massive galaxies, we unambiguously detect a clear bimodality in the (λ _{R_e}, ɛ ) diagram which may result from fundamental differences in galaxy assembly history. There is a sharp secondary density peak inside the region of the diagram with low λ _{R_e} and ɛ definition for slow rotators. Most of these galaxies are visually classified as non-regular rotators and have high velocity dispersion. The intrinsic bimodality must be stronger, as it tends to be smoothed by noise and inclination. The large sample of slow rotators allows us for the first time to unveil a secondary peak at ±90○ in their distribution of the misalignments between the photometric and kinematic position angles. We confirm that genuine slow rotators start appearing above M ≥ 2 × 1011M⊙ where a significant number of high-mass fast rotators also exist.

  1. Age-related changes of MAO-A and -B distribution in human and mouse brain.

    Science.gov (United States)

    Mahy, N; Andrés, N; Andrade, C; Saura, J

    2000-01-01

    Age-related changes of MAO-A and -B were studied in human and BL/C57 mouse brain areas (substantia nigra, putamen and cerebellum). [3H]Ro41-1049 and [3H]lazabemide were used as selective radioligands to image and quantify MAO-A and MAO-B respectively by enzyme autoradiography. MAO-A binding was higher in mouse, whereas MAO-B binding was higher in human. With aging, mouse MAO-A was significantly reduced between 4 and 8 weeks and remained unchanged until 19 months followed by a slight increase between 19 and 25 months. In contrast, no clear variation was observed in humans between the age of 17-93 years. In most of the structures studied a clear age-related increase in MAO-B was observed beginning in mouse brain at 4 weeks, whereas in human tissue this increase started at the age of 50-60 years. These results show marked differences in the levels and variations of mouse and human MAO-A and -B associated with aging and should be taken into account when extrapolating experimental data from mouse to human.

  2. Innovative Approaches to Development and Ground Testing of Advanced Bimodal Space Power and Propulsion Systems

    International Nuclear Information System (INIS)

    Hill, T.; Noble, C.; Martinell, J.; Borowski, S.

    2000-01-01

    The last major development effort for nuclear power and propulsion systems ended in 1993. Currently, there is not an initiative at either the National Aeronautical and Space Administration (NASA) or the U.S. Department of Energy (DOE) that requires the development of new nuclear power and propulsion systems. Studies continue to show nuclear technology as a strong technical candidate to lead the way toward human exploration of adjacent planets or provide power for deep space missions, particularly a 15,000 lbf bimodal nuclear system with 115 kW power capability. The development of nuclear technology for space applications would require technology development in some areas and a major flight qualification program. The last major ground test facility considered for nuclear propulsion qualification was the U.S. Air Force/DOE Space Nuclear Thermal Propulsion Project. Seven years have passed since that effort, and the questions remain the same, how to qualify nuclear power and propulsion systems for future space flight. It can be reasonably assumed that much of the nuclear testing required to qualify a nuclear system for space application will be performed at DOE facilities as demonstrated by the Nuclear Rocket Engine Reactor Experiment (NERVA) and Space Nuclear Thermal Propulsion (SNTP) programs. The nuclear infrastructure to support testing in this country is aging and getting smaller, though facilities still exist to support many of the technology development needs. By renewing efforts, an innovative approach to qualifying these systems through the use of existing facilities either in the U.S. (DOE's Advance Test Reactor, High Flux Irradiation Facility and the Contained Test Facility) or overseas should be possible

  3. Globular clusters as tracers of stellar bimodality in elliptical galaxies: the case of NGC 1399

    Science.gov (United States)

    Forte, Juan C.; Faifer, Favio; Geisler, Doug

    2005-02-01

    Globular cluster systems (GCSs) frequently show a bimodal distribution of cluster integrated colours. This work explores the arguments to support the idea that the same feature is shared by the diffuse stellar population of the galaxy they are associated with. The particular case of NGC 1399, one of the dominant central galaxies in the Fornax cluster, for which a new B surface brightness profile and (B-RKC) colours are presented, is discussed taking advantage of a recently published wide-field study of its GCS. The results show that the galaxy brightness profile and colour gradient, as well as the behaviour of the cumulative globular cluster specific frequency, are compatible with the presence of two dominant stellar populations, associated with the so-called `blue' and `red' globular cluster families. These globular families are characterized by different intrinsic specific frequencies (defined in terms of each stellar population): Sn= 3.3 +/- 0.3 in the case of the red globulars and Sn= 14.3 +/- 2.5 for the blue ones. We stress that this result does not necessarily conflict with recent works that point out a clear difference between the metallicity distribution of (resolved) halo stars and globulars when comparing their number statistics. The region within 0.5arcmin of the centre shows a deviation from the model profile (in both surface brightness and colour) that may be explained in terms of the presence of a bulge-like high-metallicity component. Otherwise, the model gives an excellent fit up to 12arcmin (or 66.5Kpc) from the centre, the galactocentric limit of our blue brightness profile. The inferred specific frequencies imply that, in terms of their associated stellar populations, the formation of the blue globulars took place with an efficiency about six times higher than that corresponding to their red counterparts. The similarity of the spatial distribution of the blue globulars with that inferred for dark matter, as well as with that of the X

  4. The Luminosity Functions of Old and Intermediate-Age Globular Clusters in NGC 3610

    OpenAIRE

    Whitmore, B. C.; Schweizer, F.; Kundu, A.; Miller, B. W.

    2002-01-01

    The WFPC2 Camera on board HST has been used to obtain high-resolution images of NGC 3610, a dynamically young elliptical galaxy. These observations supersede shorter, undithered HST observations where an intermediate-age population of globular clusters was first discovered. The new observations show the bimodal color distribution of globular clusters more clearly, with peaks at (V-I)o = 0.95 and 1.17. The luminosity function (LF) of the blue, metal-poor population of clusters in NGC 3610 turn...

  5. Ink dating, part I: Statistical distribution of selected ageing parameters in a ballpoint inks reference population.

    Science.gov (United States)

    Koenig, Agnès; Weyermann, Céline

    2018-01-01

    The development of ink dating methods requires an important amount of work in order to be reliably applicable in practice. Major tasks include the definition of ageing parameters to monitor ink ageing. An adequate parameter should ideally fulfil the following criteria: it should evolve as a function of time in a monotonic way, be measurable in a majority of ink entries, be as accurate and reproducible as possible, and finally it should not be influenced too much by transfer and storage conditions. This work aimed at evaluating the potential of seven ageing parameters for ink dating purposes: the phenoxyethanol quantity, relative peak areas (RPA), three solvent loss ratios (R%, R%*, NR%) and two solvent loss parameters (R NORM, NR NORM ). These were calculated over approximately one year for 25 inks selected from a large database to represent different ageing behaviours. Ink entries were analysed using liquid extraction followed by GC/MS analysis. Results showed that natural ageing parameters (NR% and NR NORM ) were not suitable ageing parameters for ink entries older than a few weeks. RPA used other compounds present in ink formulations in combination to PE in order to normalise the results. However, it presented particular difficulties as they could not be defined for all inks and were thus applicable only for 64% of the studied inks. Finally, the PE quantity, R% and R NORM allowed to follow the ageing of the selected inks over the whole time frame and were identified as the most promising. These were thus selected to test three different interpretation models in the second part of this article. The possibilities and limitations of ink dating methods will be discussed in a legal perspective. Copyright © 2017 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.

  6. Understanding phengite argon closure using single grain fusion age distributions in the Cycladic Blueschist Unit on Syros, Greece

    Science.gov (United States)

    Uunk, Bertram; Brouwer, Fraukje; ter Voorde, Marlies; Wijbrans, Jan

    2018-02-01

    The preservation of 40Ar/39Ar ages of high pressure (HP) metamorphic white mica reflects an interplay of processes that mobilise 40Ar, either through mica recrystallisation or by diffusive 40Ar loss. The applicability of resulting ages for dating tectonic processes is critically dependent on whether either of these processes can be proven to be efficient and exclusively active in removing 40Ar from mica. If not, preservation of an inherited or mixed age signal in a sample must be considered for interpretation. The Cycladic Blueschist Unit on Syros has become a new focal area in the discussion of the geological significance of argon age results from multi-grain step heating experiments. While some argue that age results can directly be linked to deformation or metamorphic growth events, others interpret age results to reflect the interplay of protracted recrystallisation and partial resetting, preserving a mixed age signal. Here, we demonstrate the potential of a new approach of multiple single grain fusion dating. Using the distribution of ages at the sample, section and regional scale, we show that in Northern Syros mica ages display systematic trends that can be understood as the result of three competing processes: 1) crystallisation along the prograde to peak metamorphic path, 2) a southward trend of increasing 40Ar loss by diffusion and 3) localised and rock type dependent deformation or metamorphic reactions leading to an observed age spread typically limited to ∼10 Myr at the section scale. None of the sections yielded the anomalously old age results that would be diagnostic for significant excess 40Ar. The recorded trends in ages for each of the studied sections reflect a range of P-T conditions and duration of metamorphism. Diffusion modelling shows that in a typical subduction metamorphic loop, subtle variations in P-T-t history can explain that age contrasts occur on a regional scale but are limited on the outcrop scale. Our new approach provides a

  7. Linkage disequilibrium in the insulin gene region: Size variation at the 5{prime} flanking polymorphism and bimodality among {open_quotes}Class I{close_quotes} alleles

    Energy Technology Data Exchange (ETDEWEB)

    McGinnis, R.E.; Spielman, R.S. [Univ. of Pennsylvania School of Medicine, Philadelphia, PA (United States)

    1994-09-01

    The 5{prime} flanking polymorphism (5{prime}FP), a hypervariable region at the 5{prime} end of the insulin gene, has {open_quotes}class 1{close_quotes} alleles (650-900 bp long) that are in positive linkage disequilibrium with insulin-dependent diabetes mellitus (IDDM). The authors report that precise sizing of the 5{prime}FP yields a bimodal frequency distribution of class 1 allele lengths. Class 1 alleles belonging to the lower component (650-750 bp) of the bimodal distribution were somewhat more highly associated with IDDM than were alleles from the upper component (760-900 bp), but the difference was not statistically significant. They also examined 5{prime}FP length variation in relation to allelic variation at nearby polymorphisms. At biallelic RFLPs on both sides of the 5{prime}FP, they found that one allele exhibits near-total association with the upper component of the 5FP class 1 distribution. Such associations represent a little-known but potentially wide-spread form of linkage disequilibrium. In this type of disequilibrium, a flanking allele has near-complete association with a single mode of VNTR alleles whose lengths represent consecutive numbers of tandem repeats (CNTR). Such extreme disequilibrium between a CNTR mode and flanking alleles may originate and persist because length mutations at some VNTR loci usually add or delete only one or two repeat units. 22 refs., 5 figs., 6 tabs.

  8. Trends in the distribution of gestational age and contribution of planned births in New South Wales, Australia.

    Directory of Open Access Journals (Sweden)

    Natasha Nassar

    Full Text Available BACKGROUND: There is concern that the rate of planned births (by pre-labour caesarean section or induction of labour is increasing and that the gestation at which they are being conducted is decreasing. The aim of this study was to describe trends in the distribution of gestational age, and assess the contribution of planned birth to any such changes. METHODS: We utilised the New South Wales (NSW Perinatal Data Collection to undertake a population-based study of all births in NSW, Australia 1994-2009. Trends in gestational age were determined by year, labour onset and plurality of birth. RESULTS: From 1994-2009, there was a gradual and steady left-shift in overall distribution of gestational age at birth, with a decline in the modal gestational age from 40 to 39 weeks. For singletons, there was a steady but significant reduction in the proportion of spontaneous births. Labour inductions increased in the proportion performed, with a gradual and changing shift in the distribution from a majority at 40 weeks to an increase at both 37-39 weeks and 41 weeks gestation. The proportion of pre-labour caesareans also increased steadily at each gestational age and doubled since 1994, with most performed at 39 weeks in 2009 compared with 38 weeks up to 2001. CONCLUSIONS: Findings suggest a changing pattern towards births at earlier gestations, fewer births commencing spontaneously and increasing planned births. Factors associated with changing clinical practice and long-term implications on the health and well-being of mothers and babies should be assessed.

  9. Infection rate of toxoplasma gondii and age distribution in female patients with sterility

    International Nuclear Information System (INIS)

    Li Shuhong; Dai Pei; Cui Liming; Zong Shan; Zuo Wenjing

    2006-01-01

    Objective: To discuss the relationship between the infection of Toxoplasma gondii and female sterility. Methods: Toxoplasma gondii serum antibody were determined in 882 women with sterility (experimental group) and 107 normal bearing women (control group) by using ELISA. At the same time the differences of the infection with Toxoplasma gondii between the ages of the sterility women were analyzed. Results: The positive rate in experimental group was 15.87% (140/882), the positive rate in control group was 5.61% (6/107), remarkable difference was found between two groups (P<0.01). The infection rate in the different age groups (20-24, 25-29, 30-34, 35-39 and ≥40) is 5.63%, 15.24%, 17.91%, 19.44% and 15.38%. Conclusion: Toxoplasma gondii infection may be one of the factors which can cause sterility, and the infection rates at different ages have no instinct differences. (authors)

  10. Growth rate and age distribution of deep-sea black corals in the Gulf of Mexico

    Science.gov (United States)

    Prouty, N.G.; Roark, E.B.; Buster, N.A.; Ross, Steve W.

    2011-01-01

    Black corals (order Antipatharia) are important long-lived, habitat-forming, sessile, benthic suspension feeders that are found in all oceans and are usually found in water depths greater than 30 m. Deep-water black corals are some of the slowest-growing, longest-lived deep-sea corals known. Previous age dating of a limited number of black coral samples in the Gulf of Mexico focused on extrapolated ages and growth rates based on skeletal 210Pb dating. Our results greatly expand the age and growth rate data of black corals from the Gulf of Mexico. Radiocarbon analysis of the oldest Leiopathes sp. specimen from the upper De Soto Slope at 300 m water depth indicates that these animals have been growing continuously for at least the last 2 millennia, with growth rates ranging from 8 to 22 µm yr–1. Visual growth ring counts based on scanning electron microscopy images were in good agreement with the 14C-derived ages, suggestive of annual ring formation. The presence of bomb-derived 14C in the outermost samples confirms sinking particulate organic matter as the dominant carbon source and suggests a link between the deep-sea and surface ocean. There was a high degree of reproducibility found between multiple discs cut from the base of each specimen, as well as within duplicate subsamples. Robust 14C-derived chronologies and known surface ocean 14C reservoir age constraints in the Gulf of Mexico provided reliable calendar ages with future application to the development of proxy records.

  11. Aging

    International Nuclear Information System (INIS)

    Sasaki, Hideo; Kodama, Kazunori; Yamada, Michiko

    1991-01-01

    The hypothesis that exposure to ionizing radiation accelerates the aging process has been actively investigated at ABCC-RERF since 1958, when longitudinal cohort studies of the Adult Health Study (AHS) and the Life Span Study (LSS) were initiated. In their 1975 overall review of aging studies related to the atomic bomb (A-bomb) survivors, Finch and Beebe concluded that while most studies had shown no correlation between aging and radiation exposure, they had not involved the large numbers of subjects required to provide strong evidence for or against the hypothesis. Extending LSS mortality data up to 1978 did not alter the earlier conclusion that any observed life-shortening was associated primarily with cancer induction rather than with any nonspecific cause. The results of aging studies conducted during the intervening 15 years using data from the same populations are reviewed in the present paper. Using clinical, epidemiological, and laboratory techniques, a broad spectrum of aging parameters have been studied, such as postmortem morphological changes, tests of functional capacity, physical tests and measurements, laboratory tests, tissue changes, and morbidity. With respect to the aging process, the overall results have not been consistent and are generally thought to show no relation to radiation exposure. Although some preliminary results suggest a possible radiation-induced increase in atherosclerotic diseases and acceleration of aging in the T-cell-related immune system, further study is necessary to confirm these findings. In the future, applying the latest gerontological study techniques to data collected from subjects exposed 45 years ago to A-bomb radiation at relatively young ages will present a new body of data relevant to the study of late radiation effects. (author) 103 refs

  12. Effects of aging on the cerebral distribution of technetium-99m hexamethylpropylene amine oxime in healthy humans

    Energy Technology Data Exchange (ETDEWEB)

    Mozley, P.D. [The University of Pennsylvania, Philadelphia (United States); Sadek, A.M. [The University of Cairo (Egypt); Alavi, A. [The University of Pennsylvania, Philadelphia (United States); Gur, R.C. [The University of Pennsylvania, Philadelphia (United States); Muenz, L.R. [The University of Pennsylvania, Philadelphia (United States); Bunow, B.J. [The University of Pennsylvania, Philadelphia (United States); Kim, H> J. [Yonsei University, Seoul (Korea, Republic of); Stecker, M.H. [The University of Pennsylvania, Philadelphia (United States); Jolles, P. [The Medical College of Virginia, Richmond (United States); Newberg, A. [The University of Pennsylvania, Philadelphia (United States)

    1997-07-01

    Some brain functions decline at a linear rate throughout adulthood. Others remain relatively stable until very late in the life cycle. This study characterized the effects of aging on the regional cerebral distribution of hexamethylpropylene amine oxime (HMPAO) in healthy human volunteers. The sample consisted of 26 men and 18 women with a mean age of 41.6{+-}14.9 years (range: 19-73). Their past medical histories, physical examinations, and laboratory screening tests were normal. Single-photon emission tomography (SPET) scans of the brain were performed with a standardized acquisition and processing protocol on a triple-headed camera equipped with fan beam collimators. A 3-D restorative filter and a correction for uniform attenuation were applied before the images were reinterpolated in planes parallel to the line connecting the frontal and occipital poles. Mean counts per pixel were measured in multiple regions of interest (ROIs) within each hemisphere by custom fitting a set of templates to the images. The mean activity in each ROI was compared with the mean activity per pixel in the whole brain. Regression analyses were used to relate the activity ratios to age with both linear and nonlinear models. The relative concentration of radioactivity decreased significantly with age in most, but not all, gray matter structures. It increased in the white matter regions. The nonlinear model of aging fit the data significantly better than a straight line did. Most of the changes with age occurred during young adulthood. No further changes were detectable after the onset of middle age. The median breakpoint age at which the rate of change became negligible was 36.6 years. Aging significantly affects the relative uptake of HMPAO in healthy humans. It decreases in many gray matter regions and increases in most white matter regions. However, the changes do not appear to be linear. Most seem to occur during young adulthood before people reach their late thirties. (orig

  13. An examination of bimodal nuclear power and propulsion benefits for outer solar system missions

    International Nuclear Information System (INIS)

    Zubrin, R.; Mondt, J.

    1996-01-01

    This paper presents the results of an analysis of the capability of nuclear bimodal systems to perform outer solar system exploration missions. Missions of interest include orbiter missions to Jupiter, Saturn, Uranus, Neptune, and Pluto. An initial technology baseline consisting of the NEBA 10 kWe, 1000 N thrust, 850 s, 1500 kg bimodal system was selected, and its performance examined against a data base for trajectories to outer solar system planetary destinations to select optimal direct and gravity assisted trajectories for study. A conceptual design for a common bimodal spacecraft capable of performing missions to all the planetary destinations was developed and made the basis of end to end mission designs for orbiter missions to Jupiter, Saturn, and Neptune. All mission designs considered use the Atlas 2AS for launch. The radiological hazard associated with using Earth gravity assists on such missions was examined and shown to be small compared to that currently accepted on Earth fly-by missions involving RTGs. It is shown that the bimodal nuclear power and propulsion system offers many attractive options for planetary missions, including both conventional planetary missions in which all instruments are carried by a single primary orbiting spacecraft, and unconventional missions in which the primary spacecraft acts as a carrier, relay, and mother ship for a fleet of micro spacecraft deployed at the planetary destination. copyright 1996 American Institute of Physics

  14. Spatial attention triggered by unimodal, crossmodal, and bimodal exogenous cues: a comparison of reflexive orienting mechanisms

    NARCIS (Netherlands)

    Santangelo, Valerio; van der Lubbe, Robert Henricus Johannes; Belardinelli, Marta Olivetti; Postma, Albert

    The aim of this study was to establish whether spatial attention triggered by bimodal exogenous cues acts differently as compared to unimodal and crossmodal exogenous cues due to crossmodal integration. In order to investigate this issue, we examined cuing effects in discrimination tasks and

  15. Emotional Perception of Music in Children With Bimodal Fitting and Unilateral Cochlear Implant.

    Science.gov (United States)

    Shirvani, Sareh; Jafari, Zahra; Motasaddi Zarandi, Masoud; Jalaie, Shohre; Mohagheghi, Hamed; Tale, Mohammad Reza

    2016-06-01

    Biological, structural, and acoustical constraints faced by cochlear implant (CI) users can alter the perception of music. Bimodal fitting not only provides bilateral hearing but can also improve auditory skills. This study was conducted to assess the impact of this amplification style on the emotional perception of music among children with hearing loss (HL). Twenty-five children with congenital severe to profound HL and unilateral CIs, 20 children with bimodal fitting, and 30 children with normal hearing participated in this study. Their emotional perceptions of music were measured using a method where children indicated happy or sad feelings induced by music by pointing to pictures of faces showing these emotions. Children with bimodal fitting obtained significantly higher mean scores than children with unilateral CIs for both happy and sad music items and in overall test scores (P emotional perception of music compared to unilateral CI. Given the influence of music in neurological and linguistic development and social interactions, it is important to evaluate the possible benefits of bimodal fitting prescriptions for individuals with unilateral CIs. © The Author(s) 2015.

  16. Effects of Removing Low-Frequency Electric Information on Speech Perception with Bimodal Hearing

    Science.gov (United States)

    Fowler, Jennifer R.; Eggleston, Jessica L.; Reavis, Kelly M.; McMillan, Garnett P.; Reiss, Lina A. J.

    2016-01-01

    Purpose: The objective was to determine whether speech perception could be improved for bimodal listeners (those using a cochlear implant [CI] in one ear and hearing aid in the contralateral ear) by removing low-frequency information provided by the CI, thereby reducing acoustic-electric overlap. Method: Subjects were adult CI subjects with at…

  17. Possible human impacts on adaptive radiation: beak size bimodality in Darwin's finches.

    Science.gov (United States)

    Hendry, Andrew P; Grant, Peter R; Rosemary Grant, B; Ford, Hugh A; Brewer, Mark J; Podos, Jeffrey

    2006-08-07

    Adaptive radiation is facilitated by a rugged adaptive landscape, where fitness peaks correspond to trait values that enhance the use of distinct resources. Different species are thought to occupy the different peaks, with hybrids falling into low-fitness valleys between them. We hypothesize that human activities can smooth adaptive landscapes, increase hybrid fitness and hamper evolutionary diversification. We investigated this possibility by analysing beak size data for 1755 Geospiza fortis measured between 1964 and 2005 on the island of Santa Cruz, Galápagos. Some populations of this species can display a resource-based bimodality in beak size, which mirrors the greater beak size differences among species. We first show that an historically bimodal population at one site, Academy Bay, has lost this property in concert with a marked increase in local human population density. We next show that a nearby site with lower human impacts, El Garrapatero, currently manifests strong bimodality. This comparison suggests that bimodality can persist when human densities are low (Academy Bay in the past, El Garrapatero in the present), but not when they are high (Academy Bay in the present). Human activities may negatively impact diversification in 'young' adaptive radiations, perhaps by altering adaptive landscapes.

  18. Deaf Parents of Cochlear-Implanted Children: Beliefs on Bimodal Bilingualism

    Science.gov (United States)

    Mitchiner, Julie Cantrell

    2015-01-01

    This study investigated 17 Deaf families in North America with cochlear-implanted children about their attitudes, beliefs, and practices on bimodal bilingualism (defined as using both a visual/manual language and an aural/oral language) in American Sign Language (ASL) and English. A survey and follow-up interviews with 8 families were conducted.…

  19. Reconstruction of paleodemographic characteristics from skeletal age at death distributions: perspectives from Hitotsubashi, Japan.

    Science.gov (United States)

    Nagaoka, Tomohito; Hirata, Kazuaki

    2007-11-01

    This is a demographic exploration of the city of Edo, which reveals the changes that accompanied its urbanization and analyzes the skeletal remains of 207 individuals from a specific site in Tokyo (Hitotsubashi), using several paleodemographic approaches. A comparison of the three methods employed herein suggests that the Bayesian and maximum likelihood estimation techniques provide more plausible mortality patterns than the direct method of age estimation because the direct method of age estimation relies on published age intervals for the auricular surface and that would account for the underestimation of old people relative to the other two methods. Analyses using these new approaches indicate a short life span tendency for the people of Hitotsubashi. Although we cannot rule out methodological problems of adult-age estimation, one plausible interpretation of that life expectancy is an inadequate food supply and a poor public health situation. This study suggests that, in Tokugawa Japan, urbanization might have imposed health risks, increasing the risk of mortality. Analysis of demographic data from Hitotsubashi has refined our understanding on the impact of urbanization on the Edo period, and presents new perspectives on paleodemography in Japan. (c) 2007 Wiley-Liss, Inc.

  20. How honey bees of successive age classes are distributed over a one storey, ten frames hive

    NARCIS (Netherlands)

    Steen, van der J.J.M.; Cornelissen, B.; Donders, J.N.L.C.; Blacquière, T.; Dooremalen, van C.

    2012-01-01

    In honey bee studies focusing on physiology, disease diagnosis or bio indication, bees are sampled from the colony. This raises the question of where in the colony samples must be taken from for specific study objectives. In this study we recorded where bees of known age are found in the hive. We

  1. National survey on edentulism and its geographic distribution, among Mexicans 18 years of age and older (with emphasis in WHO age groups).

    Science.gov (United States)

    Medina-Solís, C E; Pérez-Núñez, R; Maupomé, G; Avila-Burgos, L; Pontigo-Loyola, A P; Patiño-Marín, N; Villalobos-Rodelo, J J

    2008-04-01

    To determine the prevalence of edentulism in adults aged 18 years and older in Mexico and to describe its distribution in 20 of the 32 States in Mexico, highlighting the experience in the WHO age groups. A secondary analysis of the National Performance Evaluation Survey 2002-2003 (representative at the state level and part of the Word Health Survey) was undertaken. The sample design was probabilistic, stratified and through conglomerates. Data on dental conditions were available only for 20 of the 32 states of Mexico, leading to a total of 24 159 households (N = 54 638 654). The percentage of edentulism was determined as the proportion of subjects that self-reported complete loss of teeth. Data were analyzed using the SVY module for complex surveys in STATA 8.2. The mean age was 41.3 +/- 17.0 years (range 18-99). An estimated 6.3% (N = 3 437 816) of the population > or =18 years was edentulous. Lowest prevalences were observed in the states of Tlaxcala, Puebla and the Estado de Mexico with 3.4%, 3.8% and 4.5%, respectively. Highest prevalences were observed in San Luis Potosí, Colima, and Michoacán with 10.3%, 10.2% and 10.1%, respectively. Following the WHO age groups, the prevalence ranged from 2.4% in the 35-44 group through 25.5% in the 65-74 group. No obvious association between socio-economic and socio-demographic indicators at the state level and prevalence of edentulism was found. The prevalence of complete tooth loss observed in the present study varied greatly across states, although no straightforward association was found with socio-economic and socio-demographic indicators at the state level. This study could serve as a baseline to enable future evaluations of the oral status of Mexican adults and elders, following WHO age groups.

  2. Bimodal Distribution of Risk for Childhood Obesity in Urban Baja California, Mexico

    OpenAIRE

    Wojcicki, Janet M.; Jimenez-Cruz, Arturo; Bacardi-Gascon, Montserrat; Schwartz, Norah; Heyman, Melvin B.

    2012-01-01

    In Mexico, higher socioeconomic status (SES) has been found to be associated with increased risk for obesity in children. Within developed urban areas, however, there may be increased risk among lower SES children. Students in grades 4–6 from five public schools in Tijuana and Tecate, Mexico, were interviewed and weight, height and waist circumference (WC) measurements were taken. Interviews consisted of questions on food frequency, food insecurity, acculturation, physical activity and lifest...

  3. Use of bimodal carbon distribution in compacts for producing metallic iron nodules

    Science.gov (United States)

    Iwasaki, Iwao

    2012-10-16

    A method for use in production of metallic iron nodules comprising providing a reducible mixture into a hearth furnace for the production of metallic iron nodules, where the reducible mixture comprises a quantity of reducible iron bearing material, a quantity of first carbonaceous reducing material of a size less than about 28 mesh of an amount between about 65 percent and about 95 percent of a stoichiometric amount necessary for complete iron reduction of the reducible iron bearing material, and a quantity of second carbonaceous reducing material with an average particle size greater than average particle size of the first carbonaceous reducing material and a size between about 3 mesh and about 48 mesh of an amount between about 20 percent and about 60 percent of a stoichiometric amount of necessary for complete iron reduction of the reducible iron bearing material.

  4. Consideration of time-evolving capacity distributions and improved degradation models for seismic fragility assessment of aging highway bridges

    International Nuclear Information System (INIS)

    Ghosh, Jayadipta; Sood, Piyush

    2016-01-01

    This paper presents a methodology to develop seismic fragility curves for deteriorating highway bridges by uniquely accounting for realistic pitting corrosion deterioration and time-dependent capacity distributions for reinforced concrete columns under chloride attacks. The proposed framework offers distinct improvements over state-of-the-art procedures for fragility assessment of degrading bridges which typically assume simplified uniform corrosion deterioration model and pristine limit state capacities. Depending on the time in service life and deterioration mechanism, this study finds that capacity limit states for deteriorating bridge columns follow either lognormal distribution or generalized extreme value distributions (particularly for pitting corrosion). Impact of column degradation mechanism on seismic response and fragility of bridge components and system is assessed using nonlinear time history analysis of three-dimensional finite element bridge models reflecting the uncertainties across structural modeling parameters, deterioration parameters and ground motion. Comparisons are drawn between the proposed methodology and traditional approaches to develop aging bridge fragility curves. Results indicate considerable underestimations of system level fragility across different damage states using the traditional approach compared to the proposed realistic pitting model for chloride induced corrosion. Time-dependent predictive functions are provided to interpolate logistic regression coefficients for continuous seismic reliability evaluation along the service life with reasonable accuracy. - Highlights: • Realistic modeling of chloride induced corrosion deterioration in the form of pitting. • Time-evolving capacity distribution for aging bridge columns under chloride attacks. • Time-dependent seismic fragility estimation of highway bridges at component and system level. • Mathematical functions for continuous tracking of seismic fragility along service

  5. Seasonal Distribution and Diversity of Ground Arthropods in Microhabitats Following a Shrub Plantation Age Sequence in Desertified Steppe

    Science.gov (United States)

    Liu, Rentao; Zhu, Fan; Song, Naiping; Yang, Xinguo; Chai, Yongqing

    2013-01-01

    In desertified regions, shrub-dominated patches are important microhabitats for ground arthropod assemblages. As shrub age increases, soil, vegetation and microbiological properties can change remarkably and spontaneously across seasons. However, relatively few studies have analyzed how ground arthropods respond to the microhabitats created by shrubs of different plantation ages across seasons. Using 6, 15, 24 and 36 year-old plantations of re-vegetated shrubs (Caragana koushinskii) in the desert steppe of northwestern China as a model system, we sampled ground arthropod communities using a pitfall trapping method in the microhabitats under shrubs and in the open areas between shrubs, during the spring, summer and autumn. The total ground arthropod assemblage was dominated by Carabidae, Melolonthidae, Curculionidae, Tenebrionidae and Formicidae that were affected by plantation age, seasonal changes, or the interaction between these factors, with the later two groups also influenced by microhabitat. Overall, a facilitative effect was observed, with more arthropods and a greater diversity found under shrubs as compared to open areas, but this was markedly affected by seasonal changes. There was a high degree of similarity in arthropod assemblages and diversity between microhabitats in summer and autumn. Shrub plantation age significantly influenced the distribution of the most abundant groups, and also the diversity indices of the ground arthropods. However, there was not an overall positive relationship between shrub age and arthropod abundance, richness or diversity index. The influence of plantation age on arthropod communities was also affected by seasonal changes. From spring through summer to autumn, community indices of ground arthropods tended to decline, and a high degree of similarity in these indices (with fluctuation) was observed among different ages of shrub plantation in autumn. Altogether the recovery of arthropod communities was markedly affected by

  6. Distribution of Age and Location of Chordoma in 39 Cases and Review of Treatment Options

    Directory of Open Access Journals (Sweden)

    Shahab Kamali Ardekani

    2012-02-01

    Full Text Available Introduction: notochord. Although histologically benign, these tumors are locally aggressiveand present significant managment challenges . There arew some studies onevaluated the location, age and gender of the patients with Chordoma in tworeferral centers in Tehran.chordoma cases but there was no study about Iranian cases. In this study weSkull base chordomas are rare neoplasms arising from theMethods: (Shariati and Imam Hospitals, Tehran from 2001 to 2011 was retrospectivelyreviewed.A database of patients with chordoma tumors referred to two centersResults: women, and they are most commonly diagnosed in middle-aged (mean age was50.6. Tumors typically occur in the axial skeleton and have a tendency for thespheno-occipital region of the skull base and sacral region. In adults 33.3% ofchordomas involve the sacrococcygeal region, 53% occured at the base of theskull near the spheno-occipital area, and near 14% were found in the vertebralcolumn. The cranial nerves mostly affected were abducens, oculomotor andtrochlear, with some overlaps. All patients were treated with surgery and somecases referred for gamma-knife radiosurgery (GKS.In our subjects tumors affect men nearly twice as frequently asDiscussion: to females that is different from other studies, however, few studies reportedmore male to female ratio. Despite the progress in current surgical techniquesand some encouraging results with the use of targeted therapy, disease controland long-term prognosis of patients are still poor.Findings of this study showed more involvement of males compare

  7. Spatial and seasonal distribution of American whaling and whales in the age of sail.

    Directory of Open Access Journals (Sweden)

    Tim D Smith

    Full Text Available American whalemen sailed out of ports on the east coast of the United States and in California from the 18(th to early 20(th centuries, searching for whales throughout the world's oceans. From an initial focus on sperm whales (Physeter macrocephalus and right whales (Eubalaena spp., the array of targeted whales expanded to include bowhead whales (Balaena mysticetus, humpback whales (Megaptera novaeangliae, and gray whales (Eschrichtius robustus. Extensive records of American whaling in the form of daily entries in whaling voyage logbooks contain a great deal of information about where and when the whalemen found whales. We plotted daily locations where the several species of whales were observed, both those caught and those sighted but not caught, on world maps to illustrate the spatial and temporal distribution of both American whaling activity and the whales. The patterns shown on the maps provide the basis for various inferences concerning the historical distribution of the target whales prior to and during this episode of global whaling.

  8. Spatial and seasonal distribution of American whaling and whales in the age of sail.

    Science.gov (United States)

    Smith, Tim D; Reeves, Randall R; Josephson, Elizabeth A; Lund, Judith N

    2012-01-01

    American whalemen sailed out of ports on the east coast of the United States and in California from the 18(th) to early 20(th) centuries, searching for whales throughout the world's oceans. From an initial focus on sperm whales (Physeter macrocephalus) and right whales (Eubalaena spp.), the array of targeted whales expanded to include bowhead whales (Balaena mysticetus), humpback whales (Megaptera novaeangliae), and gray whales (Eschrichtius robustus). Extensive records of American whaling in the form of daily entries in whaling voyage logbooks contain a great deal of information about where and when the whalemen found whales. We plotted daily locations where the several species of whales were observed, both those caught and those sighted but not caught, on world maps to illustrate the spatial and temporal distribution of both American whaling activity and the whales. The patterns shown on the maps provide the basis for various inferences concerning the historical distribution of the target whales prior to and during this episode of global whaling.

  9. Baade's window and APOGEE. Metallicities, ages, and chemical abundances

    Science.gov (United States)

    Schultheis, M.; Rojas-Arriagada, A.; García Pérez, A. E.; Jönsson, H.; Hayden, M.; Nandakumar, G.; Cunha, K.; Allende Prieto, C.; Holtzman, J. A.; Beers, T. C.; Bizyaev, D.; Brinkmann, J.; Carrera, R.; Cohen, R. E.; Geisler, D.; Hearty, F. R.; Fernandez-Tricado, J. G.; Maraston, C.; Minnitti, D.; Nitschelm, C.; Roman-Lopes, A.; Schneider, D. P.; Tang, B.; Villanova, S.; Zasowski, G.; Majewski, S. R.

    2017-04-01

    Context. Baade's window (BW) is one of the most observed Galactic bulge fields in terms of chemical abundances. Owing to its low and homogeneous interstellar absorption it is considered the perfect calibration field for Galactic bulge studies. Aims: In the era of large spectroscopic surveys, calibration fields such as BW are necessary for cross calibrating the stellar parameters and individual abundances of the APOGEE survey. Methods: We use the APOGEE BW stars to derive the metallicity distribution function (MDF) and individual abundances for α- and iron-peak elements of the APOGEE ASPCAP pipeline (DR13), as well as the age distribution for stars in BW. Results: We determine the MDF of APOGEE stars in BW and find a remarkable agreement with that of the Gaia-ESO survey (GES). Both exhibit a clear bimodal distribution. We also find that the Mg-metallicity planes of the two surveys agree well, except for the metal-rich part ([Fe/H] > 0.1), where APOGEE finds systematically higher Mg abundances with respect to the GES. The ages based on the [C/N] ratio reveal a bimodal age distribution, with a major old population at 10 Gyr, with a decreasing tail towards younger stars. A comparison of stellar parameters determined by APOGEE and those determined by other sources reveals detectable systematic offsets, in particular for spectroscopic surface gravity estimates. In general, we find a good agreement between individual abundances of O, Na, Mg, Al, Si, K, Ca, Cr, Mn, Co, and Ni from APOGEE with that of literature values. Conclusions: We have shown that in general APOGEE data show a good agreement in terms of MDF and individual chemical abundances with respect to literature works. Using the [C/N] ratio we found a significant fraction of young stars in BW.

  10. AIDS in adults 50 years of age and over: characteristics, trends and spatial distribution of the risk1

    Science.gov (United States)

    Nogueira, Jordana de Almeida; Silva, Antônia Oliveira; de Sá, Laísa Ribeiro; de Almeida, Sandra Aparecida; Monroe, Aline Aparecida; Villa, Tereza Cristina Scatena

    2014-01-01

    Objective to analyze the sociodemographic characteristics, epidemic trend and spatial distribution of the risk of AIDS in adults 50 years of age and over. Method population-based, ecological study, that used secondary data from the Notifiable Disease Information System (Sinan/AIDS) of Paraíba state from the period January 2000 to December 2010. Results during the study period, 307 cases of AIDS were reported among people 50 years of age or over. There was a predominance of males (205/66, 8%), mixed race, and low education levels. The municipalities with populations above 100 thousand inhabitants reported 58.5% of the cases. There was a progressive increase in cases among women; an increasing trend in the incidence (positive linear correlation); and an advance in the geographical spread of the disease, with expansion to the coastal region and to the interior of the state, reaching municipalities with populations below 30 thousand inhabitants. In some locations the risk of disease was 100 times greater than the relative risk for the state. Conclusion aging, with the feminization and interiorization of the epidemic in adults 50 years of age and over, confirms the need for the induction of affirmative policies targeted toward this age group. PMID:25029044

  11. Ovulation rate and distribution in the thoroughbred mare, as determined by ultrasonic scanning: the effect of age.

    Science.gov (United States)

    Davies Morel, M C; O'Sullivan, J A

    2001-04-30

    Ovarian activity was monitored in 2181 oestrous cycles from 1136 thoroughbred brood mares to accurately determine overall ovulation rate, the relative distribution of ovulations between left and right ovary, whether mare age had an effect on these parameters and whether ovulation pattern in one cycle affected the pattern within the next. Ultrasonic scanning was used in preference to rectal palpation and slaughterhouse material due to its greater accuracy. Mare's ages ranged from 3 to 22 years. The results obtained indicated a similar incidence of ovulation occurring on the right (49.5% of all ovulations) or left ovary (50.5%). Multiple ovulations (MO) occurred in 22.4% of oestrous cycles. Significantly (Pdouble ovulations (DO) were bilateral (57.2%) than unilateral (42.8%); 20.7% were unilateral right and 22.1% were unilateral left. There were 828 mares grouped into six age groups: A (3-5 years), B (6-8 years), C (9-11 years), D (12-14 years), E (15-18 years), F (18-22 years). The distribution of ovulation between the left and right ovary was not affected by age group, but significant association (Povulations (SO) being on alternate ovaries. There was no significant repeatability of the classification of DO in one cycle compared to the next. We conclude that: (i) the mare is a symmetrical ovulator; (ii) 22.4% of cycles yield MO (ovulation rate 1.23); (iii) this MO incidence increased (P<0.01) with age; (iv) the exhibition of MO in one cycle was linked to an increased probability (P<0.01) of a MO occurring at the next one and (v) SO in one ovary was more likely (P<0.05) to be followed by a SO on the alternate ovary during the next cycle.

  12. Distribution of coronary calcium score in healthy middle-aged Korean

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Kyu Ok; Kim, Min Jung; Choi, Byoung Wook; Kim, Jung Ho; Noh, Ki Suh; Kim, Si Yon; Ko, Heung Kyu; Suh, Il [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    1999-11-01

    To determine the prevalence and degree of CAC (coronary artery calcification) in appearently healthy middle-aged Koreans, and the relation of CAC to risk factors for atherosclerosis. A total of 289 apparently healthy personnel at Yonsei University (male: 170, female:119, age: mean(SD=54.9{+-}7.1 years)) underwent EBT (electron bean tomography). The risk factors for athero-sclerosis, which included diabetes mellitus, hypertension, smoking, a family history of precocious onset, obesity, hyperlipidemia, and high intraperitoneal fat, were scrutinized. One hundred and sixty-eight subjects (58%) had at least one risk factor. The CAC score was calculated for all subjects and for each coronary artery separately and was then analyzed by age and sex and in relation to the risk factors. The prevalence of CAC was 40% in men and 18.5% in women (mean score:29.7 vs. 9.9). The number of individuals who had one, two, or more than two risk factors was 141,41, and 19, respectively. The number of risk factors and the prevalence and score of CAC were significantly correlated (p=0.01, 0.02 respectively). The number of individuals with no risk factor, with without CAC, was 58(20.1%) and 103(35.6%), respectively, while the number with some risk factor, with or without CAC, was 38(13.1%) and 90(31.1%), respectively. The CAC score was significantly higher in the presence of hypertension, low HDL, or obesity(p=0.001, 0.049, and 0.068, respectively). Smoking appeared to have a borderline effect on the calcium score(p=0.118). This study should provide useful information for interpreting CAC scores and establishing a treatment strategy for Koreans. The comparison of our results with other studies will enable a better understanding of the process and risk factors of atherosclerosis in Koreans.

  13. Distribution of coronary calcium score in healthy middle-aged Korean

    International Nuclear Information System (INIS)

    Choe, Kyu Ok; Kim, Min Jung; Choi, Byoung Wook; Kim, Jung Ho; Noh, Ki Suh; Kim, Si Yon; Ko, Heung Kyu; Suh, Il

    1999-01-01

    To determine the prevalence and degree of CAC (coronary artery calcification) in appearently healthy middle-aged Koreans, and the relation of CAC to risk factors for atherosclerosis. A total of 289 apparently healthy personnel at Yonsei University (male: 170, female:119, age: mean(SD=54.9±7.1 years) underwent EBT (electron bean tomography). The risk factors for athero-sclerosis, which included diabetes mellitus, hypertension, smoking, a family history of precocious onset, obesity, hyperlipidemia, and high intraperitoneal fat, were scrutinized. One hundred and sixty-eight subjects (58%) had at least one risk factor. The CAC score was calculated for all subjects and for each coronary artery separately and was then analyzed by age and sex and in relation to the risk factors. The prevalence of CAC was 40% in men and 18.5% in women (mean score:29.7 vs. 9.9). The number of individuals who had one, two, or more than two risk factors was 141,41, and 19, respectively. The number of risk factors and the prevalence and score of CAC were significantly correlated (p=0.01, 0.02 respectively). The number of individuals with no risk factor, with without CAC, was 58(20.1%) and 103(35.6%), respectively, while the number with some risk factor, with or without CAC, was 38(13.1%) and 90(31.1%), respectively. The CAC score was significantly higher in the presence of hypertension, low HDL, or obesity(p=0.001, 0.049, and 0.068, respectively). Smoking appeared to have a borderline effect on the calcium score(p=0.118). This study should provide useful information for interpreting CAC scores and establishing a treatment strategy for Koreans. The comparison of our results with other studies will enable a better understanding of the process and risk factors of atherosclerosis in Koreans

  14. [Colonorectal adenoma: relationships among histological structure, dimensions of the polyps, and age distribution].

    Science.gov (United States)

    Frimberger, E; Kühner, W; Seib, H J; Ottenjann, R

    1978-11-30

    Among 1258 polyps from the lower gastro-intestinal tract removed by rectoscopy or coloscopy and examined histologically there were 744 adenomas, 72% tubular, 27% papillary and 1% villous. 96.5% of all adenomas were extracted from patients aged over 40 years. Four fifths of the tumours were found in the rectum and sigmoid colon. Only 6% of the tubular adenomas were more than 15 mm in diameter, compared with 32% of papillary and 57% of villous adenomas. The special significance of the adenomas lies in their potential malignancy (adenoma-to-cancer sequence).

  15. Transverse momentum distributions of neutral pions from nuclear collisions at 200 AGeV

    CERN Document Server

    Albrecht, R; Awes, T C; Barlag, C; Bloomer, M A; Blume, C; Bock, D; Bock, R; Bohne, E M; Bucher, D; Claussen, A; Clewing, G; Eklund, A; Fokin, S; Franz, A; Garpman, S; Geurts, F; Glasow, R; Gustafsson, H °A; Gutbrod 1, H H; Hölker, G; Idh, J; Ippolitov, M; Jacobs, P; Kamermans, R; Kampert 4, K -H; Karadjev, K; Kolb, B W; Lebedev, A; L¨ohner, H; Lund, I; Manko, V; Nikolaev, S; Obenshain, F E; Oskarsson, A; Otterlund, I; Peitzmann, T; Plasil, F; Poskanzer, A M; Purschke, M; Ritter, H G; Saini, S; Santo, R; Schmidt, H R; S¨oderstrom, K; Sørensen, S P; Stankus, P; Steffens, K; Steinhaeuser, P; Stenlund, E; St¨uken, D; Twenh¨ofel, C; Vinogradov, A; Young, G R

    1998-01-01

    New results on transverse mass spectra of neutral pions measured at central rapidity are presented for impact parameter selected 200 AGeV S + S and S + Au collisions. The spectra from all systems show a clear power-law like shape with similar curvature. Collisions of S + Au exhibit a larger mean transverse momentum than pp increasing with centrality. Predictions of string models and by hydrodynamic approaches including collective expansion and decays of short lived resonances are compared to the data and the implications are discussed.

  16. Age and sex distribution of infections with Entamoeba histolytica and Giardia intestinalis in the Lagos population.

    Science.gov (United States)

    Oyerinde, J P; Ogunbi, O; Alonge, A A

    1977-09-01

    Stool samples were collected from 2,099 persons and examined for parasites: 9.5 percent were infected with Entamoeba histolytica, 7.9 percent were infected with Giardia intestinalis and 15.5 percent were infected with Iodamoeba butschlii. The infections with E. histolytica and I. butschlii occurred more frequently in females than in males and adults were also more frequently infected than children. Infection with G. intestinalis, on the other hand, was more prevalent in males than in females and children were more frequently infected than adults with the highest incidence of infection (13.8 percent) in the age-group 1-5 years.

  17. Si/Ag composite with bimodal micro-nano porous structure as a high-performance anode for Li-ion batteries.

    Science.gov (United States)

    Hao, Qin; Zhao, Dianyun; Duan, Huimei; Zhou, Qiuxia; Xu, Caixia

    2015-03-12

    A one-step dealloying method is employed to conveniently fabricate a bimodal porous (BP) Si/Ag composite in high throughput under mild conditions. Upon dealloying the carefully designed SiAgAl ternary alloy in HCl solution at room temperature, the obtained Si/Ag composite has a uniform bicontinuous porous structure in three dimensions with micro-nano bimodal pore size distribution. Compared with the traditional preparation methods for porous Si and Si-based composites, this dealloying route is easily operated and environmentally benign. More importantly, it is convenient to realize the controllable components and uniform distribution of Si and Ag in the product. Owing to the rich porosity of the unique BP structure and the incorporation of highly conductive Ag, the as-made Si/Ag composite possesses the improved conductivity and alleviated volume changes of the Si network during repeated charging and discharging. As expected, the BP Si/Ag anode exhibits high capacity, excellent cycling reversibility, long cycling life and good rate capability for lithium storage. When the current rate is up to 1 A g(-1), BP Si/Ag can deliver a stable reversible capacity above 1000 mA h g(-1), and exhibits a capacity retention of up to 89.2% against the highest capacity after 200 cycles. With the advantages of unique performance and easy preparation, the BP Si/Ag composite holds great application potential as an advanced anode material for Li-ion batteries.

  18. Distribution, spherical structure and predicted Mie scattering of multilamellar bodies in human age-related nuclear cataracts.

    Science.gov (United States)

    Gilliland, Kurt O; Freel, Christopher D; Johnsen, Sonke; Craig Fowler, W; Costello, M Joseph

    2004-10-01

    To characterize multilamellar bodies (MLBs), determine their distribution along the optic axis and predict their potential Mie scattering within human age-related nuclear cataracts. Previous studies restricted to the equatorial plane have shown that MLBs are rare spherical objects that are 1-4 microm in diameter and covered by multiple layers of thin lipid-rich membranes. Eight human aged transparent lenses were obtained from eye bank donors and eight human age-related nuclear cataracts were obtained immediately after extracapsular extraction. Each sample was Vibratome sectioned fresh into 200 microm thick sections that were fixed and embedded for light or electron microscopy. Light micrograph montages of the optic axis containing the juvenile, fetal and embryonic nuclei were examined. Mie scattering for random coated spherical particles was calculated based on assumed and measured particle parameters. Cells along the optic axis of the cataract contained approximately 7.5 times more MLBs as similar regions of the aged transparent lens, although these MLBs occurred with extremely low frequency. Cells of the aged transparent lens contained 1.3 MLBs mm(-2), while those of the cataract contained 9.6 MLBs mm(-2), which are equivalent to calculated densities of 5.6 x 10(2) and 4.1 x 10(3)mm(-3), respectively. While some MLBs were located within the cytoplasm near cell membranes, others were found away from membranes. The MLBs are distinct from circular profiles resulting from finger-like projections between adjacent cells. MLBs displayed varying geometries and cytoplasmic textures, although predominately spherical with interiors similar to adjacent fiber cell cytoplasm. These results are in agreement with previous theoretical analysis of light scattering from human lenses and with previous morphological studies examining the equatorial plane of the lens. Potential Mie scattering of spherical particles with the average properties of the observed MLBs and assumed

  19. Phylogeographic analysis elucidates the influence of the ice ages on the disjunct distribution of relict dragonflies in Asia.

    Directory of Open Access Journals (Sweden)

    Sebastian Büsse

    Full Text Available Unusual biogeographic patterns of closely related groups reflect events in the past, and molecular analyses can help to elucidate these events. While ample research on the origin of disjunct distributions of different organism groups in the Western Paleartic has been conducted, such studies are rare for Eastern Palearctic organisms. In this paper we present a phylogeographic analysis of the disjunct distribution pattern of the extant species of the strongly cool-adapted Epiophlebia dragonflies from Asia. We investigated sequences of the usually more conserved 18 S rDNA and 28 S rDNA genes and the more variable sequences of ITS1, ITS2 and CO2 of all three currently recognised Epiophlebia species and of a sample of other odonatan species. In all genes investigated the degrees of similarity between species of Epiophlebia are very high and resemble those otherwise found between different populations of the same species in Odonata. This indicates that substantial gene transfer between these populations occurred in the comparatively recent past. Our analyses imply a wide distribution of the ancestor of extant Epiophlebia in Southeast Asia during the last ice age, when suitable habitats were more common. During the following warming phase, its range contracted, resulting in the current disjunct distribution. Given the strong sensitivity of these species to climatic parameters, the current trend to increasing global temperatures will further reduce acceptable habitats and seriously threaten the existences of these last representatives of an ancient group of Odonata.

  20. Storage Dynamics and Non-Linear Connectivity between Landscape Units Control Runoff Generation and Stream Water Age Distributions

    Science.gov (United States)

    Soulsby, C.; Birkel, C.; Geris, J.; Tetzlaff, D.

    2015-12-01

    We assess the influence of storage dynamics and non-linearities in hydrological connectivity on runoff generation and stream water ages, using a long-term record of daily isotopes in precipitation and stream flow. These were used to test a parsimonious tracer-aided runoff model for a Scottish catchment. The model tracks tracers and the ages of water fluxes through and between conceptual stores representing steeper hillslopes, dynamically saturated riparian peatlands and deeper groundwater (i.e. the main landscape units involved in runoff generation). Storage is largest in groundwater and on the steep hillslopes, though most dynamic mixing occurs in smaller stores in the riparian peat. The model also couples the ecohydrological effects of different vegetation communities in contrasting landscape units, by estimating evaporation, resulting moisture deficits and the ages of evaporated waters, which also affect the generation and age of runoff. Both stream flow and isotope variations are well-captured by the model, and the simulated storage and tracer dynamics in the main landscape units are consistent with independent measurements. The model predicts the mean age of runoff as ~1.8 years. On a daily basis, this varies from ~1 month in storm events, when younger waters draining the riparian peatland dominate, to around 4 years in dry periods, when groundwater sustains flow. Hydrological connectivity between the units varies non-linearly with storage which depends upon antecedent conditions and event characteristics. This, in turn, determines the spatial distribution of flow paths and the integration of their contrasting non-stationary ages. Improving the representation of storage dynamics and quantifying the ages of water fluxes in such models gives a more complete conceptualisation of the importance of the soil water fluxes in critical zone processes and a framework for tracking diffuse pollutants in water quality assessment.

  1. Medieval Warm Period and Little Ice Age Signatures in the Distribution of Modern Ocean Temperatures

    Science.gov (United States)

    Gebbie, G.; Huybers, P. J.

    2017-12-01

    It is well established both that global temperatures have varied overthe last millenium and that the interior ocean reflects surfaceproperties inherited over these timescales. Signatures of theMedieval Warm Period and Little Ice Age are thus to be expected in themodern ocean state, though the magnitude of these effects and whetherthey are detectable is unclear. Analysis of changes in temperatureacross those obtained in the 1870s as part of the theH.M.S. Challenger expedition, the 1990s World Ocean CirculationExperiment, and recent Argo observations shows a consistent pattern:the upper ocean and Atlantic have warmed, but the oldest waters inthe deep Pacific appear to have cooled. The implications of pressureeffects on the H.M.S. Challenger thermometers and uncertainties indepth of observations are non-negligible but do not appear tofundamentally alter this pattern. Inversion of the modern hydrographyusing ocean transport estimates derived from passive tracer andradiocarbon observations indicates that deep Pacific cooling could bea vestige of the Medieval Warm Period, and that warming elsewhere reflects thecombined effects of emergence from the Little Ice Age and modernanthropogenic warming. Implications for longterm variations in oceanheat uptake and separating natural and anthropogenic contributions to themodern energy imbalance are discussed.

  2. Effects of nitrogen application rate and leaf age on the distribution pattern of leaf SPAD readings in the rice canopy.

    Directory of Open Access Journals (Sweden)

    Hu Yang

    Full Text Available A Soil-Plant Analysis Development (SPAD chlorophyll meter can be used as a simple tool for evaluating N concentration of the leaf and investigating the combined effects of nitrogen rate and leaf age on N distribution. We conducted experiments in a paddy field over two consecutive years (2008-2009 using rice plants treated with six different N application levels. N distribution pattern was determined by SPAD readings based on the temporal dynamics of N concentrations in individual leaves. At 62 days after transplantation (DAT in 2008 and DAT 60 in 2009, leaf SPAD readings increased from the upper to lower in the rice canopy that received N levels of 150 to 375 kg ha(-1The differences in SPAD readings between the upper and lower leaf were larger under higher N application rates. However, as plants grew, this atypical distribution of SPAD readings in canopy leaf quickly reversed to the general order. In addition, temporal dynamics of the leaf SPAD readings (N concentrations were fitted to a piecewise function. In our model, changes in leaf SPAD readings were divided into three stages: growth, functioning, and senescence periods. The leaf growth period lasted approximately 6 days, and cumulative growing days were not affected by N application rates. The leaf functioning period was represented with a relatively stable SPAD reading related to N application rate, and cumulative growing days were extended with increasing N application rates. A quadratic equation was utilized to describe the relationship between SPAD readings and leaf age during the leaf senescence period. The rate of decrease in SPAD readings increased with the age of leaves, but the rate was slowed by N application. As leaves in the lower canopy were physiologically older than leaves in the upper canopy, the rate of decrease in SPAD readings was faster in the lower leaves.

  3. Refractive, corneal and ocular residual astigmatism: distribution in a German population and age-dependency - the Gutenberg health study.

    Science.gov (United States)

    Schuster, Alexander Karl-Georg; Pfeiffer, Norbert; Schulz, Andreas; Hoehn, René; Ponto, Katharina A; Wild, Philipp S; Blettner, Maria; Beutel, Manfred E; Lackner, Karl J; Münzel, Thomas; Mirshahi, Alireza

    2017-12-01

    Worldwide, the most frequent cause of visual impairment is uncorrected refractive error. This analysis focused on the distribution and associations of refractive, corneal and ocular residual astigmatism. As part of the Gutenberg Health study, a population-based cross-sectional study was conducted in the general population of Germany. A comprehensive ophthalmological examination including refraction, tonometry, and Scheimpflug imaging of the anterior cornea (Pachycam) was performed. In addition to the magnitude and type (with-the-rule, against-the-rule, oblique) of the refractive or corneal astigmatism, we calculated the vector components (J 0 , J 45 ) of both astigmatisms and calculated the ocular residual astigmatism. We performed multiple quantile regression analysis to evaluate the factors associated with refractive, corneal and ocular residual astigmatisms. A total of 13,558 subjects (49% female) with a mean age of 54.0 years (range 35-74 years) were included in this study. The prevalence of refractive astigmatism (>1.0D) was 13.0% in right eyes and 12.0% in left eyes, and 85% of these subjects wore spectacles. The distribution of refractive astigmatism showed a two-peak distribution with high astigmatism for with-the-rule and against-the-rule astigmatism. The associated factors were corneal curvature, age and sex for the different astigmatisms (p prevalence of different astigmatisms within a European population. We confirmed a shift with aging from with-the-rule to against-the-rule astigmatism to refractive and corneal astigmatism. Astigmatism has a large impact on visual perception; more than 85% of people with astigmatism over one diopter wore glasses for distance vision.

  4. Children with dyslexia show a reduced processing benefit from bimodal speech information compared to their typically developing peers.

    Science.gov (United States)

    Schaadt, Gesa; van der Meer, Elke; Pannekamp, Ann; Oberecker, Regine; Männel, Claudia

    2018-01-17

    During information processing, individuals benefit from bimodally presented input, as has been demonstrated for speech perception (i.e., printed letters and speech sounds) or the perception of emotional expressions (i.e., facial expression and voice tuning). While typically developing individuals show this bimodal benefit, school children with dyslexia do not. Currently, it is unknown whether the bimodal processing deficit in dyslexia also occurs for visual-auditory speech processing that is independent of reading and spelling acquisition (i.e., no letter-sound knowledge is required). Here, we tested school children with and without spelling problems on their bimodal perception of video-recorded mouth movements pronouncing syllables. We analyzed the event-related potential Mismatch Response (MMR) to visual-auditory speech information and compared this response to the MMR to monomodal speech information (i.e., auditory-only, visual-only). We found a reduced MMR with later onset to visual-auditory speech information in children with spelling problems compared to children without spelling problems. Moreover, when comparing bimodal and monomodal speech perception, we found that children without spelling problems showed significantly larger responses in the visual-auditory experiment compared to the visual-only response, whereas children with spelling problems did not. Our results suggest that children with dyslexia exhibit general difficulties in bimodal speech perception independently of letter-speech sound knowledge, as apparent in altered bimodal speech perception and lacking benefit from bimodal information. This general deficit in children with dyslexia may underlie the previously reported reduced bimodal benefit for letter-speech sound combinations and similar findings in emotion perception. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Unimodal Versus Bimodal EEG-fMRI Neurofeedback of a Motor Imagery Task

    Directory of Open Access Journals (Sweden)

    Lorraine Perronnet

    2017-04-01

    Full Text Available Neurofeedback is a promising tool for brain rehabilitation and peak performance training. Neurofeedback approaches usually rely on a single brain imaging modality such as EEG or fMRI. Combining these modalities for neurofeedback training could allow to provide richer information to the subject and could thus enable him/her to achieve faster and more specific self-regulation. Yet unimodal and multimodal neurofeedback have never been compared before. In the present work, we introduce a simultaneous EEG-fMRI experimental protocol in which participants performed a motor-imagery task in unimodal and bimodal NF conditions. With this protocol we were able to compare for the first time the effects of unimodal EEG-neurofeedback and fMRI-neurofeedback versus bimodal EEG-fMRI-neurofeedback by looking both at EEG and fMRI activations. We also propose a new feedback metaphor for bimodal EEG-fMRI-neurofeedback that integrates both EEG and fMRI signal in a single bi-dimensional feedback (a ball moving in 2D. Such a feedback is intended to relieve the cognitive load of the subject by presenting the bimodal neurofeedback task as a single regulation task instead of two. Additionally, this integrated feedback metaphor gives flexibility on defining a bimodal neurofeedback target. Participants were able to regulate activity in their motor regions in all NF conditions. Moreover, motor activations as revealed by offline fMRI analysis were stronger during EEG-fMRI-neurofeedback than during EEG-neurofeedback. This result suggests that EEG-fMRI-neurofeedback could be more specific or more engaging than EEG-neurofeedback. Our results also suggest that during EEG-fMRI-neurofeedback, participants tended to regulate more the modality that was harder to control. Taken together our results shed first light on the specific mechanisms of bimodal EEG-fMRI-neurofeedback and on its added-value as compared to unimodal EEG-neurofeedback and fMRI-neurofeedback.

  6. Application of Bimodal Master Curve Approach on KSNP RPV steel SA508 Gr. 3

    International Nuclear Information System (INIS)

    Kim, Jongmin; Kim, Minchul; Choi, Kwonjae; Lee, Bongsang

    2014-01-01

    In this paper, the standard MC approach and BMC are applied to the forging material of the KSNP RPV steel SA508 Gr. 3. A series of fracture toughness tests were conducted in the DBTT transition region, and fracture toughness specimens were extracted from four regions, i.e., the surface, 1/8T, 1/4T and 1/2T. Deterministic material inhomogeneity was reviewed through a conventional MC approach and the random inhomogeneity was evaluated by BMC. In the present paper, four regions, surface, 1/8T, 1/4T and 1/2T, were considered for the fracture toughness specimens of KSNP (Korean Standard Nuclear Plant) SA508 Gr. 3 steel to provide deterministic material inhomogeneity and review the applicability of BMC. T0 determined by a conventional MC has a low value owing to the higher quenching rate at the surface as expected. However, more than about 15% of the KJC values lay above the 95% probability curves indexed with the standard MC T0 at the surface and 1/8T, which implies the existence of inhomogeneity in the material. To review the applicability of the BMC method, the deterministic inhomogeneity owing to the extraction location and quenching rate is treated as random inhomogeneity. Although the lower bound and upper bound curve of the BMC covered more KJC values than that of the conventional MC, there is no significant relationship between the BMC analysis lines and measured KJC values in the higher toughness distribution, and BMC and MC provide almost the same T0 values. Therefore, the standard MC evaluation method for this material is appropriate even though the standard MC has a narrow upper/lower bound curve range from the RPV evaluation point of view. The material is not homogeneous in reality. Such inhomogeneity comes in the effect of material inhomogeneity depending on the specimen location, heat treatment, and whole manufacturing process. The conventional master curve has a limitation to be applied to a large scatted data of fracture toughness such as the weld region

  7. Relationship of depression in participants with nonspecific acute or subacute low back pain and no-pain by age distribution

    Directory of Open Access Journals (Sweden)

    Calvo-Lobo C

    2017-01-01

    Full Text Available Cesar Calvo-Lobo,1 Juan Manuel Vilar Fernández,2 Ricardo Becerro-de-Bengoa-Vallejo,3 Marta Elena Losa-Iglesias,4 David Rodríguez-Sanz,5 Patricia Palomo López,6 Daniel López López7 1Physical Therapy Department, Motion in Brains Research Group, Instituto de Neurociencias y Ciencias del Movimiento, Centro Superior de Estudios Universitarios La Salle, Universidad Autónoma de Madrid, Madrid; 2Modeling, Optimization and Statistical Inference Research Group, Universidade da Coruña, A Coruña; 3School of Nursing, Physiotherapy and Podiatry, Universidad Complutense de Madrid, Madrid; 4Faculty of Health Sciences, Universidad Rey Juan Carlos, Madrid; 5Physical Therapy & Health Sciences Research Group, Facultad de Ciencias de la Salud, el Ejercicio y el Deporte, Universidad Europea de Madrid, Madrid; 6University Center of Plasencia, Universidad de Extremadura, Badajoz; 7Research, Health and Podiatry Unit, Department of Health Sciences, Faculty of Nursing and Podiatry, Universidade da Coruña, A Coruña, Spain Background and purpose: Nonspecific low back pain (LBP is the most prevalent musculoskeletal condition in various age ranges and is associated with depression. The aim of this study was to determine the Beck Depression Inventory (BDI scores in participants with nonspecific LBP and no-pain by age distribution.Methods: A case–control study was carried out following the Strengthening the Reporting of Observational Studies in Epidemiology criteria. A sample of 332 participants, divided into the following age categories: 19–24 (n=11, 25–39 (n=66, 40–64 (n=90, 65–79 (n=124, and ≥80 (n=41 years was recruited from domiciliary visits and an outpatient clinic. The BDI scores were self-reported in participants with nonspecific acute or subacute (≤3 months LBP (n=166 and no-pain (n=166.Results: The BDI scores, mean ± standard deviation, showed statistically significant differences (p<0.001 between participants with nonspecific acute or

  8. Understanding reliance on automation: effects of error type, error distribution, age and experience

    Science.gov (United States)

    Sanchez, Julian; Rogers, Wendy A.; Fisk, Arthur D.; Rovira, Ericka

    2015-01-01

    An obstacle detection task supported by “imperfect” automation was used with the goal of understanding the effects of automation error types and age on automation reliance. Sixty younger and sixty older adults interacted with a multi-task simulation of an agricultural vehicle (i.e. a virtual harvesting combine). The simulator included an obstacle detection task and a fully manual tracking task. A micro-level analysis provided insight into the way reliance patterns change over time. The results indicated that there are distinct patterns of reliance that develop as a function of error type. A prevalence of automation false alarms led participants to under-rely on the automation during alarm states while over relying on it during non-alarms states. Conversely, a prevalence of automation misses led participants to over-rely on automated alarms and under-rely on the automation during non-alarm states. Older adults adjusted their behavior according to the characteristics of the automation similarly to younger adults, although it took them longer to do so. The results of this study suggest the relationship between automation reliability and reliance depends on the prevalence of specific errors and on the state of the system. Understanding the effects of automation detection criterion settings on human-automation interaction can help designers of automated systems make predictions about human behavior and system performance as a function of the characteristics of the automation. PMID:25642142

  9. The decline of the Fossil Age is the rise of distributive justice

    Directory of Open Access Journals (Sweden)

    Stephan Bannas

    2011-02-01

    st century, energy is the source, the prerequisite and the legitimation of the model of power and consumption of the last century. However, there is neither the material basis nor the energy availability for us to pursue further, and around the globe, the resource-hungry and energy-hungry lifestyle of the past decades. This lifestyle never brought happiness (cp. Kasser, 2002. It could never be achieved throughout the world. Today, energy no longer embodies the genie from the bottle, who works wonders, but rather a model for limitless economic growth, material excess and the accumulation of economic, social and political power by one group at the expense of the others. Energy is frequently seen as being synonymous with the climatic and ecological crisis, with greenhouse gases, global injustice and military conflicts. At the same time, though, energy today once again represents hope. The age of renewable energy has dawned and, with its potential for decentralised production, its polycentric supply infrastructure and ecological balance, it represents a new technological age. Renewable energy gives new strength to ideas of good governance, of justice, participation and stewardship of our social goods.

  10. [Development of national and international standards of population age distribution for medical statistics, health-demographic analysis and risk assessment].

    Science.gov (United States)

    Demin, V F; Pal'tsev, M A; Chaban, E A

    2013-01-01

    The current European standard (CES) and the World population age distribution standard is widely used in medical and demographic studies, performed by international (WHO, etc.) and national organizations. The Russian Federal Service of States Statistics (RosStat) uses CES in demographic yearbooks and other publications. The standard is applied in calculation of the standardized mortality rate (SMR) of the population in different countries and territories. Risk assessment is also used CES. In the basis of the standards there has been laid the idea to assess mortality according to uniform standard, so to get possibility to compare the mortality rate of the population in different countries and regions, different genders and different calendar years. Analysis of the results of test calculations of the values of the SMR for the population of Russia and other countries with the use of current standards has revealed serious shortcomings of the latters and set up the task of improving them. A new concept of the development of standards based on the use of the concept of stable equilibrium of the age distribution of the population and survivorship function is proposed.

  11. Geographic distribution of HIV stigma among women of childbearing age in rural Kenya

    Science.gov (United States)

    Akullian, Adam; Kohler, Pamela; Kinuthia, John; Laserson, Kayla; Mills, Lisa A.; Okanda, John; Olilo, George; Ombok, Maurice; Odhiambo, Frank; Rao, Deepa; Wakefield, Jonathan; John-Stewart, Grace

    2015-01-01

    Objective(s) HIV stigma is considered to be a major driver of the HIV/AIDS pandemic, yet there is a limited understanding of its occurrence. We describe the geographic patterns of two forms of HIV stigma in a cross-sectional sample of women of childbearing age from western Kenya: internalized stigma (associated with shame) and externalized stigma (associated with blame). Design Geographic studies of HIV stigma provide a first step in generating hypotheses regarding potential community-level causes of stigma and may lead to more effective community-level interventions. Methods Spatial regression using generalized additive models and point pattern analyses using K-functions were used to assess the spatial scale(s) at which each form of HIV stigma clusters, and to assess whether the spatial clustering of each stigma indicator was present after adjustment for individual-level characteristics. Results There was evidence that externalized stigma (blame) was geographically heterogeneous across the study area, even after controlling for individual-level factors (P=0.01). In contrast, there was less evidence (P=0.70) of spatial trend or clustering of internalized stigma (shame). Conclusion Our results may point to differences in the underlying social processes motivating each form of HIV stigma. Externalized stigma may be driven more by cultural beliefs disseminated within communities, whereas internalized stigma may be the result of individual-level characteristics outside the domain of community influence. These data may inform community-level interventions to decrease HIV-related stigma, and thus impact the HIV epidemic. PMID:24835356

  12. DASH diet score and distribution of blood pressure in middle-aged men and women.

    Science.gov (United States)

    Harrington, Janas M; Fitzgerald, Anthony P; Kearney, Patricia M; McCarthy, Vera J C; Madden, Jamie; Browne, Gemma; Dolan, Eamon; Perry, Ivan J

    2013-11-01

    The Dietary Approaches to Stop Hypertension (DASH) Trial provides critical data on the impact of a specific diet pattern (low in salt, fat, and processed foods and high in fruit and vegetables) on blood pressure (BP). The effect of compliance with a DASH-type diet on BP in a general population sample is less well defined. We studied associations between a DASH style diet and BP. We used cross-sectional data from a study of men and women aged 47-73 years (n = 2,047). Participants completed a physical examination that included 3 standardized clinical BP recordings. A subsample (n = 1,187) had ambulatory BP measurements (ABPM) taken. Diet was assessed using a DASH dietary score constructed from a standard Food Frequency Questionnaire. Lower scores indicated less healthy diets. Hypertension was defined as clinic BP ≥ 140/90 mm Hg on medication or as 24-hour ABPM ≥ 130/80 mmHg. Inverse associations were evident between DASH and systolic BP (SBP). There was a difference in clinic SBP of 7.5 mm Hg and 5.1 mm Hg and a difference in ABPM SBP of 6.3mm Hg and 5.4mm Hg in men and women, respectively, between the highest and lowest DASH quintiles. In fully adjusted multivariable regression analysis, DASH score was inversely associated with SBP. Clear population differences in SBP were evident across DASH quintiles. The observed associations indicate that the findings are consistent with the hypothesis that adherence to DASH-equivalent diet can reduce BP at the population level. Public policy promoting a DASH-style healthy diet could have a significant impact on population health by reducing average BP in the population. © American Journal of Hypertension, Ltd 2013. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Age and petrogenetic constraints on the Lower Glassy Ignimbrite of the Mount Somers Volcanic Group, New Zealand

    DEFF Research Database (Denmark)

    van der Meer, Quinten; Waight, Tod Earle; Whitehouse, Martin

    2017-01-01

    The Mount Somers Volcanic Group (MSVG) forms a large (~18000 km2) calc-alkaline volcanic complex on New Zealand’s Eastern Province. U-Pb SIMS spot ages on zircon from the lower glassy ignimbrite in Rakaia Gorge reveal a bimodal distribution of 99.0 ± 0.5 and 96.3 ± 0.5 Ma (2σ). These ages...... are within error of previous (unpublished) zircon SHRIMP ages but have a precision that enables identification of two distinct episodes of zircon crystallisation, indicating magmatic activity over a period of at least 2.5 Ma. The younger age is interpreted to represent the emplacement age of the ignimbrite....... The older age may originate from the assimilation of underlying ignimbrites or prolonged magma chamber processes. Combined O and Hf isotopes in zircon indicate that melt compositions for the ~99 Ma and ~96 Ma magmatic episodes were very similar and intermediate between the local upper crust and mantle...

  14. Emotional Intensity Modulates the Integration of Bimodal Angry Expressions: ERP Evidence

    Directory of Open Access Journals (Sweden)

    Zhihui Pan

    2017-06-01

    Full Text Available Integration of information from face and voice plays a central role in social interactions. The present study investigated the modulation of emotional intensity on the integration of facial-vocal emotional cues by recording EEG for participants while they were performing emotion identification task on facial, vocal, and bimodal angry expressions varying in emotional intensity. Behavioral results showed the rates of anger and reaction speed increased as emotional intensity across modalities. Critically, the P2 amplitudes were larger for bimodal expressions than for the sum of facial and vocal expressions for low emotional intensity stimuli, but not for middle and high emotional intensity stimuli. These findings suggested that emotional intensity modulates the integration of facial-vocal angry expressions, following the principle of Inverse Effectiveness (IE in multimodal sensory integration.

  15. Formation of bimodal porous silica-titania monoliths by sol-gel route

    Energy Technology Data Exchange (ETDEWEB)

    Ruzimuradov, O N, E-mail: ruzimuradov@rambler.ru [Department of General Chemistry, Faculty of Chemistry, National University of Uzbekistan, 15, Vuzgorodok, Tashkent, 100174 (Uzbekistan)

    2011-10-29

    Silica-titania monoliths with micrometer-scale macroporous and nanometer-scale mesoporous structure and high titania contents are prepared by sol-gel process and phase separation. Titanium alkoxide precursor was not effective in the preparation of high titania content composites because of strong decrease in phase separation tendency. Bimodal porous gels with high titania content were obtained by using inorganic salt precursors such as titanium sulfate and titanium chloride. Various characterization techniques, including SEM, XRD, Hg porosimetry and N{sub 2} adsorption have been carried out to investigate the formation process and physical-chemical properties of silica-titania monoliths. The characterization results show that the silica-titania monoliths possess a bimodal porous structure with well-dispersed titania inside silica network. The addition of titania in silica improves the thermal stability of both macroporous and mesoporous structures.

  16. Abundance inhomogeneities and atmospheric structure in CN-bimodal globular cluster giants

    Science.gov (United States)

    Drake, Jeremy J.; Plez, Bertrand; Smith, Verne V.

    1993-01-01

    It has been suggested by several authors that the sodium and aluminum abundance variations correlating with CN-band strength, frequently observed in CN-bimodal globular cluster giants, could be spurious manifestations of different temperature structures in the 'CN-strong' and 'CN-weak' stars, caused by different molecular line blanketing related to the C, N, and O trio. For stellar parameters generally appropriate to giants in the intermediate metallicity CN-bimodal cluster M4, we demonstrate through new model atmosphere calculations, employing opacity sampling and spherical geometry, that the observed abundance anomalies cannot be the result of atmospheric temperature structure. Our results using spherical geometry are compared to identical calculations performed with plane-parallel geometry: the effects of atmospheric extension on derived abundances for all lines considered amount to less than 0.1 dex.

  17. A simple hydrothermal route to bimodal mesoporous nanorod {gamma}-alumina with high thermal stability

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiang; Han, Dezhi; Xue, Hongxia; Liu, Xinmei; Yan, Zifeng [China Univ. of Petroleum, Qingdao (China). State Key Lab. of Heavy Oil Processing

    2011-12-15

    In the presence of polyethylene glycol, bimodal mesoporous nanorod {gamma}-alumina was successfully synthesized via the thermal decomposition of ammonium aluminium carbonate hydroxide precursor which was prepared via hydrothermal processing with inorganic aluminium salt. The alumina exhibits high surface area (494 m{sup 2}g{sup -1}), large porosity (1.1 m{sup 3}g{sup -1}) and a particular double-pore structure after calcination at 500 C. The smaller pore diameter is concentrated on about 3 nm and the larger one is exhibited in the range of 10 - 38 nm. The scaffold-like aggregation of {gamma}-alumina nanorods endows this novel material with excellent thermal stability. A possible formation mechanism of bimodal mesoporous structure is also proposed in this study. (orig.)

  18. HCV genotypes and age distribution in patients of Vienna and surrounding areas.

    Science.gov (United States)

    Haushofer, A C; Kopty, C; Hauer, R; Brunner, H; Halbmayer, W M

    2001-01-01

    Chronic hepatitis C (CHC) can result in liver cirrhosis and hepatocellular carcinoma. Determination of the hepatitis C virus (HCV) genotype/subtype may be of prognostic value to estimate the risk of development of liver cirrhosis. The HCV genotype/subtype was determined in patients with CHC and possible associations with age, source of HCV transmission, duration of HCV infection, and development of liver cirrhosis were investigated. A total of 250 consecutive patients with CHC were studied. HCV genotypes/subtypes were determined with a commercially available assay based on the reverse-hybridization principle. Source of HCV transmission and duration of HCV infection were taken from the patient documentation and liver cirrhosis was diagnosed by clinical, biochemical, and sonographic data. HCV genotypes 1, 2, 3, 4, and 5 were found in 74.8, 2.8, 16, 5.2, and 0.4% of the patients. Most frequent subtypes were 1b (54%), 1a (15.6%), and 3a (15.6%). Patients with genotype 1 (mean, 52.8 years) or 2 (mean, 51.0 years) were significantly older than patients with genotype 3 (mean, 37.2 years) or genotype 4 (mean, 37.2 years). Patients with subtype 1b (mean, 58.1 years) were significantly older than patients with subtype 1a (mean, 40.8 years) or 3a (mean, 37.5 years). The main sources of HCV infection were intravenous drug abuse in 30.0% of all patients (genotype 1 in 53.3%; genotype 3 in 40%) or transfusion of blood and blood products in 21.6% of all patients (genotype 1 in 83.4%). The source of transmission, however, remained unknown in 44.8% of all patients. The prevalence of genotype 1 was significantly higher in patients with long duration (more than 20 years) of CHC. In none of the patients with genotype 2 or 3, duration of CHC for more than 20 years was observed. The prevalence of genotype 4 was significantly higher in patients with short duration (less than 10 years) of CHC. Liver cirrhosis was diagnosed in 13.6% of all patients (97.1% of patients with genotype 1

  19. Differential distribution of age and HBV serological markers in liver cirrhosis and non-cirrhotic patients with primary liver cancer

    Directory of Open Access Journals (Sweden)

    XU Xiuhua

    2013-03-01

    Full Text Available ObjectiveTo compare the age distributions and presence of hepatitis B virus (HBV serological markers between primary hepatic cancer (PHC patients with and without liver cirrhosis. MethodsA total of 547 PHC cases were analyzed retrospectively. After dividing into two groups according to liver cirrhosis status, the between-group differences in age and HBV serological markers, such as hepatitis B e antigen (HBeAg status, were statistically compared using the Chi-squared test. ResultsThe number of cirrhotic and non-cirrhotic PHC patients was 265 and 282, respectively. HBV infection was present in 221 cirrhotic PHC patients and 256 non-cirrhotic PHC patients (834% vs. 90.8%. There was a substantial bias in the proportion of males to females in the cirrhotic PHC patients (7.83∶1. The number of PHC patients <60 years old was similar between the cirrhotic and non-cirrhotic groups, but the non-cirrhotic group had significantly more patients >60 years old (P<0.005. In cirrhotic PHC patients, the HBV infection rate was highest in the <40 years old age group (96.7% and the HBeAg serological conversion rate was highest in the 40-60 years old age group (89.5%. In non-cirrhotic PHC patients, the 40-60 years old age group showed the highest HBV infection rate (90.3% but the lowest HBeAg serological conversion rate (80.0%. ConclusionPHC with liver cirrhosis mainly occurred in males, with the HBV infection rate being higher in individuals <60 years old. Non-cirrhotic PHC patients were more often >60 years old. Many of the HBV-infected PHC patients with cirrhosis had high HBeAg serological conversion rate.

  20. Stream water age distributions controlled by storage dynamics and nonlinear hydrologic connectivity: Modeling with high‐resolution isotope data

    Science.gov (United States)

    Birkel, C.; Geris, J.; Dick, J.; Tunaley, C.; Tetzlaff, D.

    2015-01-01

    Abstract To assess the influence of storage dynamics and nonlinearities in hydrological connectivity on time‐variant stream water ages, we used a new long‐term record of daily isotope measurements in precipitation and streamflow to calibrate and test a parsimonious tracer‐aided runoff model. This can track tracers and the ages of water fluxes through and between conceptual stores in steeper hillslopes, dynamically saturated riparian peatlands, and deeper groundwater; these represent the main landscape units involved in runoff generation. Storage volumes are largest in groundwater and on the hillslopes, though most dynamic mixing occurs in the smaller stores in riparian peat. Both streamflow and isotope variations are generally well captured by the model, and the simulated storage and tracer dynamics in the main landscape units are consistent with independent measurements. The model predicts that the average age of stream water is ∼1.8 years. On a daily basis, this varies between ∼1 month in storm events, when younger waters draining the hillslope and riparian peatland dominates, to around 4 years in dry periods when groundwater sustains flow. This variability reflects the integration of differently aged water fluxes from the main landscape units and their mixing in riparian wetlands. The connectivity between these spatial units varies in a nonlinear way with storage that depends upon precipitation characteristics and antecedent conditions. This, in turn, determines the spatial distribution of flow paths and the integration of their contrasting nonstationary ages. This approach is well suited for constraining process‐based modeling in a range of northern temperate and boreal environments. PMID:27478255

  1. Stream water age distributions controlled by storage dynamics and nonlinear hydrologic connectivity: Modeling with high-resolution isotope data.

    Science.gov (United States)

    Soulsby, C; Birkel, C; Geris, J; Dick, J; Tunaley, C; Tetzlaff, D

    2015-09-01

    To assess the influence of storage dynamics and nonlinearities in hydrological connectivity on time-variant stream water ages, we used a new long-term record of daily isotope measurements in precipitation and streamflow to calibrate and test a parsimonious tracer-aided runoff model. This can track tracers and the ages of water fluxes through and between conceptual stores in steeper hillslopes, dynamically saturated riparian peatlands, and deeper groundwater; these represent the main landscape units involved in runoff generation. Storage volumes are largest in groundwater and on the hillslopes, though most dynamic mixing occurs in the smaller stores in riparian peat. Both streamflow and isotope variations are generally well captured by the model, and the simulated storage and tracer dynamics in the main landscape units are consistent with independent measurements. The model predicts that the average age of stream water is ∼1.8 years. On a daily basis, this varies between ∼1 month in storm events, when younger waters draining the hillslope and riparian peatland dominates, to around 4 years in dry periods when groundwater sustains flow. This variability reflects the integration of differently aged water fluxes from the main landscape units and their mixing in riparian wetlands. The connectivity between these spatial units varies in a nonlinear way with storage that depends upon precipitation characteristics and antecedent conditions. This, in turn, determines the spatial distribution of flow paths and the integration of their contrasting nonstationary ages. This approach is well suited for constraining process-based modeling in a range of northern temperate and boreal environments.

  2. Brain deactivation in the outperformance in bimodal tasks: an FMRI study.

    Directory of Open Access Journals (Sweden)

    Tzu-Ching Chiang

    Full Text Available While it is known that some individuals can effectively perform two tasks simultaneously, other individuals cannot. How the brain deals with performing simultaneous tasks remains unclear. In the present study, we aimed to assess which brain areas corresponded to various phenomena in task performance. Nineteen subjects were requested to sequentially perform three blocks of tasks, including two unimodal tasks and one bimodal task. The unimodal tasks measured either visual feature binding or auditory pitch comparison, while the bimodal task required performance of the two tasks simultaneously. The functional magnetic resonance imaging (fMRI results are compatible with previous studies showing that distinct brain areas, such as the visual cortices, frontal eye field (FEF, lateral parietal lobe (BA7, and medial and inferior frontal lobe, are involved in processing of visual unimodal tasks. In addition, the temporal lobes and Brodmann area 43 (BA43 were involved in processing of auditory unimodal tasks. These results lend support to concepts of modality-specific attention. Compared to the unimodal tasks, bimodal tasks required activation of additional brain areas. Furthermore, while deactivated brain areas were related to good performance in the bimodal task, these areas were not deactivated where the subject performed well in only one of the two simultaneous tasks. These results indicate that efficient information processing does not require some brain areas to be overly active; rather, the specific brain areas need to be relatively deactivated to remain alert and perform well on two tasks simultaneously. Meanwhile, it can also offer a neural basis for biofeedback in training courses, such as courses in how to perform multiple tasks simultaneously.

  3. Ecological, phenological and biochemical significance of bimodal fruiting of Boletus alutaceus morgan

    OpenAIRE

    Nandkumar Kamat

    2009-01-01

    Boletus alutaceus Morgan an ectomycorrhizal species was extensively studied from an ecologically fragmented microhabitt colonized by its' host plant Ficus benghalensis L. in the Goa University campus, Taleigao, Goa, India. Qualitatively the fruiting cycles were monitored for three years and thereafter detail ecological and morphological investigations were carried out in May and November 2004. A bimodal temporal fruting pattern emerged which may have significant ecological, phenological ...

  4. Age determination of 15 old to intermediate-age small Magellanic cloud star clusters

    International Nuclear Information System (INIS)

    Parisi, M. C.; Clariá, J. J.; Piatti, A. E.; Geisler, D.; Leiton, R.; Carraro, G.; Costa, E.; Grocholski, A. J.; Sarajedini, A.

    2014-01-01

    We present color-magnitude diagrams in the V and I bands for 15 star clusters in the Small Magellanic Cloud (SMC) based on data taken with the Very Large Telescope (VLT, Chile). We selected these clusters from our previous work, wherein we derived cluster radial velocities and metallicities from calcium II infrared triplet (CaT) spectra also taken with the VLT. We discovered that the ages of six of our clusters have been appreciably underestimated by previous studies, which used comparatively small telescopes, graphically illustrating the need for large apertures to obtain reliable ages of old and intermediate-age SMC star clusters. In particular, three of these clusters, L4, L6, and L110, turn out to be among the oldest SMC clusters known, with ages of 7.9 ± 1.1, 8.7 ± 1.2, and 7.6 ± 1.0 Gyr, respectively, helping to fill a possible 'SMC cluster age gap'. Using the current ages and metallicities from Parisi et al., we analyze the age distribution, age gradient, and age-metallicity relation (AMR) of a sample of SMC clusters measured homogeneously. There is a suggestion of bimodality in the age distribution but it does not show a constant slope for the first 4 Gyr, and we find no evidence for an age gradient. Due to the improved ages of our cluster sample, we find that our AMR is now better represented in the intermediate/old period than we had derived in Parisi et al., where we simply took ages available in the literature. Additionally, clusters younger than ∼4 Gyr now show better agreement with the bursting model of Pagel and Tautvaišienė, but we confirm that this model is not a good representation of the AMR during the intermediate/old period. A more complicated model is needed to explain the SMC chemical evolution in that period.

  5. Uterine cervix cancer treatment at Radiumhemmet: 90 years′ experience. Time trends of age, stage, and histopathology distribution

    International Nuclear Information System (INIS)

    Hellman, Kristina; Hellström, Ann-Cathrin; Pettersson, B Folke

    2014-01-01

    Since the introduction of screening programs for cervical cancer (CC) the incidence has decreased and CC is discovered at an earlier stage. The purpose of this study was to analyze time trends in age, stage, and histopathology over a 90-year period and to our knowledge this is the largest single institutional series in the literature of invasive cervical carcinoma (CC) cases. This is a retrospective study comprising 18,472 women treated for CC from 1914 until 2004 at Radiumhemmet, Stockholm. The material is part of the international CC statistics published since 1937 in the League of Nations' Annual Reports, and since 1958 under the patronage of International Federation of Gynecology and Obstetrics (FIGO). During the 90-year study period, the annual number of cases treated increased to over 400 up until 1965, after which there was a gradual drop to less than 100 cases in 2004. A pronounced shift toward earlier stages at diagnosis was noted. The mean age at diagnosis increased in all stages, predominantly in advanced stages. A reduction in squamous cell carcinoma (SCC) cases and a sixfold increase in the proportion of adenocarcinoma (AC) cases were observed. The mean age at diagnosis for squamous and AC cases shifted after 1970, when the SCC cases ultimately became 3 years older than the AC cases in contrast to around 1950 when they were 3 years younger than the AC cases. The changes in the distribution by age, stage, and histopathology during this 90-year period are probably associated with: improved social conditions and increased access to health care, the introduction of screening programs for CC in the 1960s, and a change in the risk factors for CC (changed sexual behavior, introduction of contraceptive pills, and changed smoking habits). This is a study on changes in the distribution by age, stage, and histopathology in a large series of cervical cancer treated in Sweden during a 90-year period. It also includes an historical review about the development

  6. Uterine cervix cancer treatment at Radiumhemmet: 90 years′ experience. Time trends of age, stage, and histopathology distribution

    Science.gov (United States)

    Hellman, Kristina; Hellström, Ann-Cathrin; Pettersson, B Folke

    2014-01-01

    Since the introduction of screening programs for cervical cancer (CC) the incidence has decreased and CC is discovered at an earlier stage. The purpose of this study was to analyze time trends in age, stage, and histopathology over a 90-year period and to our knowledge this is the largest single institutional series in the literature of invasive cervical carcinoma (CC) cases. This is a retrospective study comprising 18,472 women treated for CC from 1914 until 2004 at Radiumhemmet, Stockholm. The material is part of the international CC statistics published since 1937 in the League of Nations' Annual Reports, and since 1958 under the patronage of International Federation of Gynecology and Obstetrics (FIGO). During the 90-year study period, the annual number of cases treated increased to over 400 up until 1965, after which there was a gradual drop to less than 100 cases in 2004. A pronounced shift toward earlier stages at diagnosis was noted. The mean age at diagnosis increased in all stages, predominantly in advanced stages. A reduction in squamous cell carcinoma (SCC) cases and a sixfold increase in the proportion of adenocarcinoma (AC) cases were observed. The mean age at diagnosis for squamous and AC cases shifted after 1970, when the SCC cases ultimately became 3 years older than the AC cases in contrast to around 1950 when they were 3 years younger than the AC cases. The changes in the distribution by age, stage, and histopathology during this 90-year period are probably associated with: improved social conditions and increased access to health care, the introduction of screening programs for CC in the 1960s, and a change in the risk factors for CC (changed sexual behavior, introduction of contraceptive pills, and changed smoking habits). This is a study on changes in the distribution by age, stage, and histopathology in a large series of cervical cancer treated in Sweden during a 90-year period. It also includes an historical review about the development of

  7. Pluto/Charon exploration utilizing a bi-modal PBR nuclear propulsion/power system

    Science.gov (United States)

    Venetoklis, Peter S.

    1995-01-01

    The paper describes a Pluto/Charon orbiter utilizing a bi-modal nuclear propulsion and power system based on the Particle Bed Reactor. The orbiter is sized for launch to Nuclear-Safe orbit atop a Titan IV or equivalent launch veicle. The bi-modal system provides thermal propulsion for Earth orbital departure and Pluto orbital capture, and 10 kWe of electric power for payload functions and for in-system maneuvering with ion thrusters. Ion thrusters are used to perform inclination changes about Pluto, a transfer from low Pluto orbit to low Charon orbit, and inclination changes about charon. A nominal payload can be deliverd in as little as 15 years, 1000 kg in 17 years, and close to 2000 kg in 20 years. Scientific return is enormously aided by the availability of up to 10 kWe, due to greater data transfer rates and more/better instruments. The bi-modal system can provide power at Pluto/Charon for 10 or more years, enabling an extremely robust, scientifically rewarding, and cost-effective exploration mission.

  8. RSMASS-D nuclear thermal propulsion and bimodal system mass models

    Science.gov (United States)

    King, Donald B.; Marshall, Albert C.

    1997-01-01

    Two relatively simple models have been developed to estimate reactor, radiation shield, and balance of system masses for a particle bed reactor (PBR) nuclear thermal propulsion concept and a cermet-core power and propulsion (bimodal) concept. The approach was based on the methodology developed for the RSMASS-D models. The RSMASS-D approach for the reactor and shield sub-systems uses a combination of simple equations derived from reactor physics and other fundamental considerations along with tabulations of data from more detailed neutron and gamma transport theory computations. Relatively simple models are used to estimate the masses of other subsystem components of the nuclear propulsion and bimodal systems. Other subsystem components include instrumentation and control (I&C), boom, safety systems, radiator, thermoelectrics, heat pipes, and nozzle. The user of these models can vary basic design parameters within an allowed range to achieve a parameter choice which yields a minimum mass for the operational conditions of interest. Estimated system masses are presented for a range of reactor power levels for propulsion for the PBR propulsion concept and for both electrical power and propulsion for the cermet-core bimodal concept. The estimated reactor system masses agree with mass predictions from detailed calculations with xx percent for both models.

  9. Die Bonding Performance Using Bimodal Cu Particle Paste Under Different Sintering Atmospheres

    Science.gov (United States)

    Gao, Yue; Zhang, Hao; Li, Wanli; Jiu, Jinting; Nagao, Shijo; Sugahara, Tohru; Suganuma, Katsuaki

    2017-07-01

    A one-step polyol method was employed to synthesize bimodal Cu particles with average diameters around 200 nm and 1000 nm, respectively. The bimodal Cu particles were mixed with a reductive solvent of polyethylene glycol (PEG) to form a paste. The Cu paste was used as die bonding material to prepare Cu joints under N2 or vacuum sintering atmosphere. The results showed that the strength of the Cu joints in N2 atmosphere was always higher than that in vacuum. The shear strength of a Cu joint processed at 350°C under only 0.4 MPa bonding pressure in N2 was above 40 MPa, which was far higher than that obtained using single-sized nano-Cu particle paste. It is related to the dense packing of the bimodal Cu particles and slow decomposition behavior of the reductive PEG solvent. The reductive PEG solvent in the Cu paste, which effectively removed oxides on the surface of the Cu particles, was necessary for easy-oxidized Cu pastes. These results suggested that Cu pastes with suitable particle sizes, reducing solvent and sintering atmosphere could be a proper candidate for low-temperature and low-pressure bonding process.

  10. Thermal decomposition behavior of nano/micro bimodal feedstock with different solids loading

    Science.gov (United States)

    Oh, Joo Won; Lee, Won Sik; Park, Seong Jin

    2018-01-01

    Debinding is one of the most critical processes for powder injection molding. The parts in debinding process are vulnerable to defect formation, and long processing time of debinding decreases production rate of whole process. In order to determine the optimal condition for debinding process, decomposition behavior of feedstock should be understood. Since nano powder affects the decomposition behavior of feedstock, nano powder effect needs to be investigated for nano/micro bimodal feedstock. In this research, nano powder effect on decomposition behavior of nano/micro bimodal feedstock has been studied. Bimodal powders were fabricated with different ratios of nano powder, and the critical solids loading of each powder was measured by torque rheometer. Three different feedstocks were fabricated for each powder depending on solids loading condition. Thermogravimetric analysis (TGA) experiment was carried out to analyze the thermal decomposition behavior of the feedstocks, and decomposition activation energy was calculated. The result indicated nano powder showed limited effect on feedstocks in lower solids loading condition than optimal range. Whereas, it highly influenced the decomposition behavior in optimal solids loading condition by causing polymer chain scission with high viscosity.

  11. Second language experience modulates functional brain network for the native language production in bimodal bilinguals.

    Science.gov (United States)

    Zou, Lijuan; Abutalebi, Jubin; Zinszer, Benjamin; Yan, Xin; Shu, Hua; Peng, Danling; Ding, Guosheng

    2012-09-01

    The functional brain network of a bilingual's first language (L1) plays a crucial role in shaping that of his or her second language (L2). However, it is less clear how L2 acquisition changes the functional network of L1 processing in bilinguals. In this study, we demonstrate that in bimodal (Chinese spoken-sign) bilinguals, the functional network supporting L1 production (spoken language) has been reorganized to accommodate the network underlying L2 production (sign language). Using functional magnetic resonance imaging (fMRI) and a picture naming task, we find greater recruitment of the right supramarginal gyrus (RSMG), the right temporal gyrus (RSTG), and the right superior occipital gyrus (RSOG) for bilingual speakers versus monolingual speakers during L1 production. In addition, our second experiment reveals that these regions reflect either automatic activation of L2 (RSOG) or extra cognitive coordination (RSMG and RSTG) between both languages during L1 production. The functional connectivity between these regions, as well as between other regions that are L1- or L2-specific, is enhanced during L1 production in bimodal bilinguals as compared to their monolingual peers. These findings suggest that L1 production in bimodal bilinguals involves an interaction between L1 and L2, supporting the claim that learning a second language does, in fact, change the functional brain network of the first language. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Inter-laboratory comparison on the size and stability of monodisperse and bimodal synthetic reference particles for standardization of extracellular vesicle measurements

    Science.gov (United States)

    Nicolet, Anaïs; Meli, Felix; van der Pol, Edwin; Yuana, Yuana; Gollwitzer, Christian; Krumrey, Michael; Cizmar, Petr; Buhr, Egbert; Pétry, Jasmine; Sebaihi, Noham; de Boeck, Bert; Fokkema, Vincent; Bergmans, Rob; Nieuwland, Rienk

    2016-03-01

    In future, measurements of extracellular vesicles in body fluids could become a standard diagnostic tool in medicine. For this purpose, reliable and traceable methods, which can be easily applied in hospitals, have to be established. Within the European Metrological Research Project (EMRP) ‘Metrological characterization of micro-vesicles from body fluids as non-invasive diagnostic biomarkers’ (www.metves.eu), various nanoparticle reference materials were developed and characterized. We present results of an international comparison among four national metrology institutes and a university hospital. The size distributions of five monodisperse and two bimodal spherical particle samples with diameters ranging from 50 nm to 315 nm made out of silica and polystyrene were compared. Furthermore, the stability of the samples was verified over a period of 18 months. While monodisperse reference particle samples above a certain size level lead to good agreements of the size measurements among the different methods, small and bimodal samples show the limitations of current ‘clinical’ methods. All samples proved to be stable within the uncertainty of the applied methods.

  13. Inter-laboratory comparison on the size and stability of monodisperse and bimodal synthetic reference particles for standardization of extracellular vesicle measurements

    International Nuclear Information System (INIS)

    Nicolet, Anaïs; Meli, Felix; Van der Pol, Edwin; Yuana, Yuana; Nieuwland, Rienk; Gollwitzer, Christian; Krumrey, Michael; Cizmar, Petr; Buhr, Egbert; Pétry, Jasmine; Sebaihi, Noham; De Boeck, Bert; Fokkema, Vincent; Bergmans, Rob

    2016-01-01

    In future, measurements of extracellular vesicles in body fluids could become a standard diagnostic tool in medicine. For this purpose, reliable and traceable methods, which can be easily applied in hospitals, have to be established. Within the European Metrological Research Project (EMRP) ‘Metrological characterization of micro-vesicles from body fluids as non-invasive diagnostic biomarkers’ (www.metves.eu), various nanoparticle reference materials were developed and characterized. We present results of an international comparison among four national metrology institutes and a university hospital. The size distributions of five monodisperse and two bimodal spherical particle samples with diameters ranging from 50 nm to 315 nm made out of silica and polystyrene were compared. Furthermore, the stability of the samples was verified over a period of 18 months. While monodisperse reference particle samples above a certain size level lead to good agreements of the size measurements among the different methods, small and bimodal samples show the limitations of current ‘clinical’ methods. All samples proved to be stable within the uncertainty of the applied methods. (paper)

  14. Chlamydia trachomatis, human immunodeficiency virus (HIV distribution and sexual behaviors across gender and age group in an African setting.

    Directory of Open Access Journals (Sweden)

    Joel Fleury Djoba Siawaya

    Full Text Available OBJECTIVE: The purpose of this study was to (1 describe the distribution of Chlamydia trachomatis (CT and Human Immunodeficiency Virus (HIV cases across gender and age groups in Libreville (Gabon; (2 examine Gabonese Sexually Transmitted Infections (STIs-related risk behaviour. METHODS: The sampled population was people attending the "Laboratoire National de Santé Plublique". Between 2007 and 2011, 14 667 and 9 542 people respectively, were tested for CT and HIV infections. 1 854 of them were tested for both infections. We calculated CT and HIV rates across gender and age groups. Also analysed was the groups' contribution to the general CT and HIV epidemiology. STIs-related risk behaviours were assessed in 224 men and 795 women (between July 2011 and March 2013 who agreed and answered a questionnaire including questions on their marital status, number of sex partners, sexual practices, history of STIs, sex frequency and condom use. RESULTS: Data showed a 24% dropped in the CT infection rate between 2007 and 2010, followed by a 14% increase in 2011. The HIV infection rates for the same period were between 15% and 16%. The risk of a CT-positive subject getting HIV is about 0.71 times the risk of a CT-negative subject. Young adult aged between 18 and 35 years old represented 65.2% of people who had STIs. 80% of women and 66% of men confessed to an inconsistent use of condoms. 11.6% of women and 48% of men declared having multiple sex partners. 61% of questioned women and 67% of men declared knowing their HIV status. CONCLUSIONS: In this Gabonese setting, the population-aged from 18 to 35 years is the most affected by STIs. Other matters of concern are the inconsistent use of protection and sex with non-spousal or non-life partners.

  15. Uterine cervix cancer treatment at Radiumhemmet: 90 years' experience. Time trends of age, stage, and histopathology distribution.

    Science.gov (United States)

    Hellman, Kristina; Hellström, Ann-Cathrin; Pettersson, B Folke

    2014-04-01

    Since the introduction of screening programs for cervical cancer (CC) the incidence has decreased and CC is discovered at an earlier stage. The purpose of this study was to analyze time trends in age, stage, and histopathology over a 90-year period and to our knowledge this is the largest single institutional series in the literature of invasive cervical carcinoma (CC) cases. This is a retrospective study comprising 18,472 women treated for CC from 1914 until 2004 at Radiumhemmet, Stockholm. The material is part of the international CC statistics published since 1937 in the League of Nations' Annual Reports, and since 1958 under the patronage of International Federation of Gynecology and Obstetrics (FIGO). During the 90-year study period, the annual number of cases treated increased to over 400 up until 1965, after which there was a gradual drop to less than 100 cases in 2004. A pronounced shift toward earlier stages at diagnosis was noted. The mean age at diagnosis increased in all stages, predominantly in advanced stages. A reduction in squamous cell carcinoma (SCC) cases and a sixfold increase in the proportion of adenocarcinoma (AC) cases were observed. The mean age at diagnosis for squamous and AC cases shifted after 1970, when the SCC cases ultimately became 3 years older than the AC cases in contrast to around 1950 when they were 3 years younger than the AC cases. The changes in the distribution by age, stage, and histopathology during this 90-year period are probably associated with: improved social conditions and increased access to health care, the introduction of screening programs for CC in the 1960s, and a change in the risk factors for CC (changed sexual behavior, introduction of contraceptive pills, and changed smoking habits). © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  16. Age-specific bone tumour incidence rates are governed by stem cell exhaustion influencing the supply and demand of progenitor cells.

    Science.gov (United States)

    Richardson, Richard B

    2014-07-01

    Knudson's carcinogenic model, which simulates incidence rates for retinoblastoma, provides compelling evidence for a two-stage mutational process. However, for more complex cancers, existing multistage models are less convincing. To fill this gap, I hypothesize that neoplasms preferentially arise when stem cell exhaustion creates a short supply of progenitor cells at ages of high proliferative demand. To test this hypothesis, published datasets were employed to model the age distribution of osteochondroma, a benign lesion, and osteosarcoma, a malignant one. The supply of chondrogenic stem-like cells in femur growth plates of children and adolescents was evaluated and compared with the progenitor cell demand of longitudinal bone growth. Similarly, the supply of osteoprogenitor cells from birth to old age was compared with the demands of bone formation. Results show that progenitor cell demand-to-supply ratios are a good risk indicator, exhibiting similar trends to the unimodal and bimodal age distributions of osteochondroma and osteosarcoma, respectively. The hypothesis also helps explain Peto's paradox and the finding that taller individuals are more prone to cancers and have shorter lifespans. The hypothesis was tested, in the manner of Knudson, by its ability to convincingly explain and demonstrate, for the first time, a bone tumour's bimodal age-incidence curve. Crown Copyright © 2014. Published by Elsevier Ireland Ltd. All rights reserved.

  17. Age-specific differences in influenza virus type and subtype distribution in the 2012/2013 season in 12 European countries

    DEFF Research Database (Denmark)

    Beauté, J; Zucs, P; Korsun, N

    2015-01-01

    that the overall distribution of circulating (sub)types may mask substantial differences between age groups. Thus, in cases aged 5-14 years, 75% tested positive for influenza B virus whereas all other age groups had an even distribution of influenza A and B viruses. This means that the intepretation of syndromic......The epidemiology of seasonal influenza is influenced by age. During the influenza season, the European Influenza Surveillance Network (EISN) reports weekly virological and syndromic surveillance data [mostly influenza-like illness (ILI)] based on national networks of sentinel primary-care providers....... Aggregated numbers by age group are available for ILI, but not linked to the virological data. At the end of the influenza season 2012/2013, all EISN laboratories were invited to submit a subset of their virological data for this season, including information on age. The analysis by age group suggests...

  18. Osteoprotegerin levels decrease during testosterone therapy in aging men and are associated with changed distribution of regional fat.

    Science.gov (United States)

    Frederiksen, L; Glintborg, D; Højlund, K; Hougaard, D M; Brixen, K; Rasmussen, L M; Andersen, M

    2013-04-01

    The cardiovascular effects of testosterone treatment are debated. Osteoprotegerin (OPG) is an independent marker of cardiovascular risk. We investigated the effect of testosterone therapy on OPG levels in aging men with low normal bioavailable testosterone levels. A randomized, double-blinded, placebo-controlled study of 6 months testosterone therapy (gel) in 38 men aged 60-78 years with bioavailable testosterone 94 cm was performed. Clinical evaluation, OPG, and C-reactive protein (CRP) measurements were carried out. Lean body mass (LBM), total fat mass, and bone mineral density (BMD) were established by dual X-ray absorptiometry. Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were measured by magnetic resonance imaging. Power calculation was based on an increase in LBM during testosterone therapy and responders were defined as testosterone treated patients with increased LBM (Δ LBM positive), n=14. Data are presented as median (interquartile range). Testosterone therapy decreased total fat mass and SAT, whereas VAT was unchanged (n=38). OPG levels decreased during testosterone therapy (from 2.0 (1.9-2.5) to 1.9 (1.6-2.2) ng/ml, ptestosterone therapy (n=14), ΔOPG levels were inversely associated with ΔSAT (r= - 0.60, p=0.03) and positively associated with ΔVAT (r=0.56, p=0.04). OPG levels decreased during testosterone therapy suggesting decreased cardiovascular risk. Decreased OPG levels were associated with changes in regional fat distribution and future studies are needed to further evaluate the association between OPG and regional fat mass distribution. © Georg Thieme Verlag KG Stuttgart · New York.

  19. Distribution of sensory taste thresholds for phenylthiocarbamide ...

    African Journals Online (AJOL)

    The ability to taste Phenylthiocarbamide (PTC), a bitter organic compound has been described as a bimodal autosomal trait in both genetic and anthropological studies. This study is based on the ability of a person to taste PTC. The present study reports the threshold distribution of PTC taste sensitivity among some Muslim ...

  20. Quantifying the distribution of nanodiamonds in pre-Younger Dryas to recent age deposits along Bull Creek, Oklahoma panhandle, USA.

    Science.gov (United States)

    Bement, Leland C; Madden, Andrew S; Carter, Brian J; Simms, Alexander R; Swindle, Andrew L; Alexander, Hanna M; Fine, Scott; Benamara, Mourad

    2014-02-04

    High levels of nanodiamonds (nds) have been used to support the transformative hypothesis that an extraterrestrial (ET) event (comet explosion) triggered Younger Dryas changes in temperature, flora and fauna assemblages, and human adaptations [Firestone RB, et al. (2007) Proc Natl Acad Sci USA 104(41):16016-16021]. We evaluate this hypothesis by establishing the distribution of nds within the Bull Creek drainage of the Beaver River basin in the Oklahoma panhandle. The earlier report of an abundance spike of nds in the Bull Creek I Younger Dryas boundary soil is confirmed, although no pure cubic diamonds were identified. The lack of hexagonal nds suggests Bull Creek I is not near any impact site. Potential hexagonal nds at Bull Creek were found to be more consistent with graphene/graphane. An additional nd spike is found in deposits of late Holocene through the modern age, indicating nds are not unique to the Younger Dryas boundary. Nd distributions do not correlate with depositional environment, pedogenesis, climate perturbations, periods of surface stability, or cultural activity.

  1. Epidemiology of Plasmodium knowlesi malaria in north-east Sabah, Malaysia: family clusters and wide age distribution.

    Science.gov (United States)

    Barber, Bridget E; William, Timothy; Dhararaj, Prabakaran; Anderios, Fread; Grigg, Matthew J; Yeo, Tsin W; Anstey, Nicholas M

    2012-12-05

    The simian parasite Plasmodium knowlesi is a common cause of human malaria in Malaysian Borneo, with a particularly high incidence in Kudat, Sabah. Little is known however about the epidemiology in this substantially deforested region. Malaria microscopy records at Kudat District Hospital were retrospectively reviewed from January 2009-November 2011. Demographics, and PCR results if available, were recorded for each positive result. Medical records were reviewed for patients suspected of representing family clusters, and families contacted for further information. Rainfall data were obtained from the Malaysian Meteorological Department. "Plasmodium malariae" mixed or mono-infection was diagnosed by microscopy in 517/653 (79%) patients. Of these, PCR was performed in 445 (86%) and was positive for P. knowlesi mono-infection in 339 (76%). Patients with knowlesi malaria demonstrated a wide age distribution (median 33, IQR 20-50, range 0.7-89 years) with P. knowlesi predominating in all age groups except those Sabah, including potential for human-to-human transmission, are needed.

  2. End plate marrow changes in the asymptomatic lumbosacral spine: frequency, distribution and correlation with age and degenerative changes

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Christine B. [Department of Radiology, VA Healthcare System, 3350 La Jolla Village Drive, CA 92161, La Jolla (United States); Vande Berg, Bruno C.; Malghem, Jacques [Department of Radiology, Cliniques Universitaires St Luc Universite Catholique de Louvain, 10 av Hippocrate, 1200, Brussels (Belgium); Tavernier, Thierry [Service de Radiologie, Clinique de la Sauvegarde, Av David Ben Gourion, 69009, Lyon (France); Cotten, Anne [Service de Radiologie Osteoarticulaire, Hopital R Salengro, 59037, Lille Cedex (France); Laredo, Jean-Denis [Service de Radiologie Osteo-articulaire, Hopital Lariboisiere, 2 rue Ambroise Pare, 75475, Paris Cedex 10 (France); Vallee, Christian [Service d' imagerie medicale, Hopital Raymond Poincare, 104 Boulevard R.Poincare, 92380, Garches (France)

    2004-07-01

    To investigate the frequency and distribution of end plate marrow signal intensity changes in an asymptomatic population and to correlate these findings with patient age and degenerative findings in the spine. MR imaging studies of the lumbosacral (LS) spine in 59 asymptomatic subjects were retrospectively reviewed by 2 musculoskeletal radiologists to determine the presence and location of fat-like and edema-like marrow signal changes about the end plates of the L1-2 through L5-S1 levels. The presence of degenerative changes in the spine was recorded as was patient age. Descriptive statistics were utilized to determine the frequency and associations of end plate findings and degenerative changes in the spine. Interobserver variability was determined by a kappa score. Binomial probability was used to predict the prevalence of the end plate changes in a similar subject population. The Fisher exact test was performed to determine statistical significance of the relationship of end plate changes with degenerative changes in the spine, superior versus inferior location about the disc and age of the patient population. Focal fat-like signal intensity adjacent to the vertebral end-plate was noted in 15 out of 59 subjects by both readers, and involved 38 and 36 out of 590 end plates by readers 1 and 2, respectively. Focal edema-like signal intensity adjacent to the vertebral end plate was noted in 8 out of 59 subjects by both readers and involved 11 and 10 out of 590 end plates by readers 1 and 2, respectively. Either fat or edema signal intensity occurred most often at the anterior (p<.05) aspects of the mid-lumbar spine and was seen in an older sub-population of the study (p<.05). End plate marrow signal intensity changes are present in the lumbar spine of some asymptomatic subjects with a characteristic location along the spine and in vertebral end plates. (orig.)

  3. End plate marrow changes in the asymptomatic lumbosacral spine: frequency, distribution and correlation with age and degenerative changes

    International Nuclear Information System (INIS)

    Chung, Christine B.; Vande Berg, Bruno C.; Malghem, Jacques; Tavernier, Thierry; Cotten, Anne; Laredo, Jean-Denis; Vallee, Christian

    2004-01-01

    To investigate the frequency and distribution of end plate marrow signal intensity changes in an asymptomatic population and to correlate these findings with patient age and degenerative findings in the spine. MR imaging studies of the lumbosacral (LS) spine in 59 asymptomatic subjects were retrospectively reviewed by 2 musculoskeletal radiologists to determine the presence and location of fat-like and edema-like marrow signal changes about the end plates of the L1-2 through L5-S1 levels. The presence of degenerative changes in the spine was recorded as was patient age. Descriptive statistics were utilized to determine the frequency and associations of end plate findings and degenerative changes in the spine. Interobserver variability was determined by a kappa score. Binomial probability was used to predict the prevalence of the end plate changes in a similar subject population. The Fisher exact test was performed to determine statistical significance of the relationship of end plate changes with degenerative changes in the spine, superior versus inferior location about the disc and age of the patient population. Focal fat-like signal intensity adjacent to the vertebral end-plate was noted in 15 out of 59 subjects by both readers, and involved 38 and 36 out of 590 end plates by readers 1 and 2, respectively. Focal edema-like signal intensity adjacent to the vertebral end plate was noted in 8 out of 59 subjects by both readers and involved 11 and 10 out of 590 end plates by readers 1 and 2, respectively. Either fat or edema signal intensity occurred most often at the anterior (p<.05) aspects of the mid-lumbar spine and was seen in an older sub-population of the study (p<.05). End plate marrow signal intensity changes are present in the lumbar spine of some asymptomatic subjects with a characteristic location along the spine and in vertebral end plates. (orig.)

  4. Distribution of blood pressure & correlates of hypertension in school children aged 5-14 years from North East India.

    Science.gov (United States)

    Borah, Prasanta Kr; Devi, Utpala; Biswas, Dipankar; Kalita, Hem Ch; Sharma, Meenakshi; Mahanta, Jagadish

    2015-09-01

    Elevated blood pressure (BP) in the young predicts serious cardiovascular events in the adults. High prevalence of adult hypertension reported from Assam, North East (NE) India may be linked with elevated blood pressure in the childhood. The present study was an attempt to describe the distribution of BP and correlates of hypertension in children aged 5-14 yr. A total of 10,003 school children from 99 schools of Dibrugarh district, Assam, NE India, were surveyed by stratified random cluster method. Blood pressure, demographic and anthropometric information were recorded. Blood pressure was categorized in to normal, prehypertension, stage I and stage II hypertension. Girls had significantly higher (104.2 ± 12.0 vs. 103.2 ± 11.6 mm Hg, p0 <0.001) mean systolic blood pressure (SBP) than boys. Both SBP and diastolic blood pressure (DBP) revealed significant correlation with age, height, weight and BMI in overall and in gender specific analysis. Hypertension was found in 7.6 per cent school children (Boys: 7.3%, Girls: 7.8%). In multivariable analysis older age (OR 3.3, 95% CI: 2.82-3.91), children from tea garden community (OR 1.3, 95% CI: 1.08-1.55) and other community (OR 1.4, 95% CI: 1.18-1.73) and overweight (OR 1.5, 95% CI: 1.1-2.1) were independently associated with hypertension. Mean blood pressure in the young school children of 5-14 yr was high. A programme comprising screening, early detection and health promotion through school health programmes may help prevent future complications of hypertension.

  5. Oncogenic Nras has bimodal effects on stem cells that sustainably increase competitiveness.

    Science.gov (United States)

    Li, Qing; Bohin, Natacha; Wen, Tiffany; Ng, Victor; Magee, Jeffrey; Chen, Shann-Ching; Shannon, Kevin; Morrison, Sean J

    2013-12-05

    'Pre-leukaemic' mutations are thought to promote clonal expansion of haematopoietic stem cells (HSCs) by increasing self-renewal and competitiveness; however, mutations that increase HSC proliferation tend to reduce competitiveness and self-renewal potential, raising the question of how a mutant HSC can sustainably outcompete wild-type HSCs. Activating mutations in NRAS are prevalent in human myeloproliferative neoplasms and leukaemia. Here we show that a single allele of oncogenic Nras(G12D) increases HSC proliferation but also increases reconstituting and self-renewal potential upon serial transplantation in irradiated mice, all prior to leukaemia initiation. Nras(G12D) also confers long-term self-renewal potential to multipotent progenitors. To explore the mechanism by which Nras(G12D) promotes HSC proliferation and self-renewal, we assessed cell-cycle kinetics using H2B-GFP label retention and 5-bromodeoxyuridine (BrdU) incorporation. Nras(G12D) had a bimodal effect on HSCs, increasing the frequency with which some HSCs divide and reducing the frequency with which others divide. This mirrored bimodal effects on reconstituting potential, as rarely dividing Nras(G12D) HSCs outcompeted wild-type HSCs, whereas frequently dividing Nras(G12D) HSCs did not. Nras(G12D) caused these effects by promoting STAT5 signalling, inducing different transcriptional responses in different subsets of HSCs. One signal can therefore increase HSC proliferation, competitiveness and self-renewal through bimodal effects on HSC gene expression, cycling and reconstituting potential.

  6. Processing bimodal stimulus information under alcohol: is there a risk to being redundant?

    Science.gov (United States)

    Fillmore, Mark T

    2010-10-01

    The impairing effects of alcohol are especially pronounced in environments that involve dividing attention across two or more stimuli. However, studies in cognitive psychology have identified circumstances in which the presentation of multiple stimuli can actually facilitate performance. The "redundant signal effect" (RSE) refers to the observation that individuals respond more quickly when information is presented as redundant, bimodal stimuli (e.g., aurally and visually), rather than as a single stimulus presented to either modality alone. The present study tested the hypothesis that the response facilitation attributed to RSE could reduce the degree to which alcohol slows information processing. Two experiments are reported. Experiment 1 demonstrated the validity of a reaction time model of RSE by showing that adults (N = 15) responded more quickly to redundant, bimodal stimuli (visual + aural) versus either stimuli presented individually. Experiment 2 used the RSE model to test the reaction time performance of 20 adults following three alcohol doses (0.0 g/kg, 0.45 g/kg, and 0.65 g/kg). Results showed that alcohol slowed reaction time in a general dose-dependent manner in all three stimulus conditions with the reaction time (RT) speed-advantage of the redundant signal being maintained, even under the highest dose of alcohol. Evidence for an RT advantage to bimodal stimuli under alcohol challenges the general assumption that alcohol impairment is intensified in multistimulus environments. The current study provides a useful model to investigate how drug effects on behavior might be altered in contexts that involve redundant response signals.

  7. Comparison of metabolic profile and abdominal fat distribution between karyotypically normal women with premature ovarian insufficiency and age matched controls.

    Science.gov (United States)

    Ates, Seda; Yesil, Gozde; Sevket, Osman; Molla, Taner; Yildiz, Seyma

    2014-11-01

    We designed a prospective case-control study in order to investigate the lipid profiles, insulin sensitivity, presence of metabolic syndrome (MetS) and the abdominal fat distribution in karyotypically normal women with premature ovarian insufficiency (POI). Anthropometric measurements, FSH, estradiol, total testosterone (T), sex hormone binding globulin (SHBG), free androgen index (FAI), fasting glucose and insulin, homeostatic model for insulin resistance (HOMA-IR), lipid profile, the prevalence of MetS and ultrasonographic abdominal fat measurements were assessed in 56 women with POI and 59 healthy controls at the same age range. Serum levels of T, SHBG and FAI were not significantly different between both groups. Total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) were higher in women with POI. There were no differences in glucose, insulin, HOMA-IR, low-density lipoprotein cholesterol (LDL-C), triglyceride levels between the two groups. A significant positive correlation was identified between T and TG and also between FAI and LDL-C; SHBG levels were correlated inversely with FSH, and positively with HDL-C in women with POI. The presence of MetS was significantly higher in women with POI. The subcutaneous, preperitoneal and visceral fat thicknesses were not significantly different between the groups. Early cessation of ovulatory function may associated with higher levels of serum TC and HDL-C, but does not seem to cause differences in abdominal fat distribution in women with POI. POI is associated with higher risk of MetS. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  8. A floodplain mesocosm study: Distribution, mobility, aging, and functioning of engineered silver nanoparticles at the aquatic-terrestrial interface

    Science.gov (United States)

    Metreveli, George; Kurtz, Sandra; Philippe, Allan; Tayyebi, Narjes; Seitz, Frank; Rosenfeldt, Ricki R.; Grün, Alexandra; Kumahor, Samuel K.; Baumann, Thomas; Bundschuh, Mirco; Lang, Friederike; Klitzke, Sondra; Manz, Werner; Schulz, Ralf; Vogel, Hans-Jörg; Schaumann, Gabriele E.

    2017-04-01

    With increasing use of engineered nanoparticles (ENPs) in different commercial products the risk for their release into the environment is continuously increased. The aging, distribution, mobility, biological availability, and ecotoxicological impact of ENPs in aquatic and terrestrial compartments will be influenced especially by the natural dynamics of meadow areas, which represent a sensible zone between these two compartments. In this study we present a newly developed floodplain stream mesocosm system linking aquatic and terrestrial aging of ENPs in one system. Using this system we investigated the distribution, mobility, and biological effects of silver nanoparticles (Ag NPs) at the aquatic-terrestrial interface. The mesocosm consists of a main channel, floodplain area, and transport columns simulating an aquatic compartment with river bed, aquatic-terrestrial transition zone, and terrestrial area, respectively. The system contained water sampled from the River Rhine, quartz sand as sediment phase and natural repacked soil from a Rhine floodplain. Every 3 weeks floodplain area was flooded for four days by increasing the water level in the main channel. The dispersions of Ag NPs were injected into the main channel as a pulse function with the pulse duration of 3 weeks and interval of 3 weeks between pulses. The biological effects of Ag NPs on the benthic organism Gammarus fossarum were evaluated in the bioassays during and between the Ag NP pulses. The total duration of the experiment was 33 weeks. The results of mesocosm experiments showed a fluctuating but successively increasing concentrations of total silver in the aqueous phase. At the end of the experiment 0.5% of the silver was still available in the aqueous phase mostly as nanoparticles. Although the major part of silver was immobilized in sediment and soil especially in their top layer, the feeding activity of Gammarus fossarum was not consistently affected. It is most likely due to the low

  9. Impact of Bimodal Traffic on Latency in Optical Burst Switching Networks

    Directory of Open Access Journals (Sweden)

    Yuhua Chen

    2008-01-01

    Full Text Available This paper analyzes the impact of bimodal traffic composition on latency in optical burst switching networks. In particular, it studies the performance degradation to short-length packets caused by longer packets, both of which are part of a heterogeneous traffic model. The paper defines a customer satisfaction index for each of the classes of traffic, and a composite satisfaction index. The impact of higher overall utilization of the network as well as that of the ratio of the traffic mix on each of the customer satisfaction indices is specifically addressed.

  10. A bimodal temom model for particle Brownian coagulation in the continuum-slip regime

    Directory of Open Access Journals (Sweden)

    He Qing

    2016-01-01

    Full Text Available In this paper, a bimodal Taylor-series expansion moment of method is proposed to deal with Brownian coagulation in the continuum-slip regime, where the non-linear terms in the Cunningham correction factor is approximated by Taylor-series expansion technology. The results show that both the number concentration and volume fraction decrease with time in the smaller mode due to the intra and inter coagulation, and the asymptotic behavior of the larger mode is as same as that in the continuum regime.

  11. Association between body fat distribution and androgen deficiency in middle-aged and elderly men in China.

    Science.gov (United States)

    Ren, Y; Wang, B; Liu, X; Li, Z; Yuan, W; Sun, Y; Miao, M

    2014-01-01

    The objective of the present study was to examine the association between body fat distribution and total testosterone (TT) and free testosterone (FT) levels among middle-aged and elderly men. A total of 922 male residents aged 40-70 years from a community in Shanghai, China, participated in the study. Their waist circumference (WC), waist-height ratio (WHtR), body mass index (BMI), and TT and FT concentrations were measured. Logistic regression models were used to estimate testosterone deficiency risk on the basis of anthropometric indices. BMI, WC and WHtR were all associated with TT deficiency. The participants in the highest quartiles of above-mentioned anthropometric indices had the highest risk of TT deficiency (BMI: odds ratio (OR)=4.40, 95% confidence interval (CI)=2.69-7.19; WC: OR=3.47, 95% CI=2.14-5.60; WHtR: OR=2.89, 95% CI=1.76-4.76). WC and WHtR were associated with FT deficiency. The participants in the highest quartiles had the highest risk of FT deficiency (WC: OR=1.87, 95% CI=1.18-2.97; WHtR: OR=1.67, 95% CI=1.04-2.66). The association between BMI and FT deficiency was not statistically significant (OR=1.21 for the highest quartile, 95% CI=0.78-1.87). Our study demonstrated that both general and abdominal obesity were associated with TT deficiency, whereas only abdominal obesity was found to be associated with FT deficiency.

  12. Effect of Topography Degradation on Crater Size-Frequency Distributions: Implications for Populations of Small Craters and Age Dating

    Science.gov (United States)

    Xie, Minggang; Zhu, Meng-Hua; Xiao, Zhiyong; Wu, Yunzhao; Xu, Aoao

    2017-10-01

    Whether or not background secondary craters dominate populations of small impact craters on terrestrial bodies is a half-century controversy. It has been suggested that small craters on some planetary bodies are dominated by background secondary craters based partly on the steepened slope of crater size-frequency distribution (CSFD) toward small diameters, such as the less than 1 km diameter crater population on the lunar mare. Here we show that topography degradation enlarges craters and increases CSFD slopes with time. When topography degradation is taken into account, for various-aged crater populations, the observed steep CSFD at small diameters is uniformly consistent with an originally shallower CSFD, whose slope is undifferentiated from the CSFD slope estimated from near-Earth objects and terrestrial bolides. The results show that the effect of topography degradation on CSFD is important in dating planetary surfaces, and the steepening of CSFD slopes is not necessarily caused by secondary cratering, but rather a natural consequence of topography degradation.

  13. STAR CLUSTERS IN M31. II. OLD CLUSTER METALLICITIES AND AGES FROM HECTOSPEC DATA

    International Nuclear Information System (INIS)

    Caldwell, Nelson; Schiavon, Ricardo; Morrison, Heather; Harding, Paul; Rose, James A.

    2011-01-01

    We present new high signal-to-noise spectroscopic data on the M31 globular cluster (GC) system, obtained with the Hectospec multifiber spectrograph on the 6.5 m MMT. More than 300 clusters have been observed at a resolution of 5 A and with a median S/N of 75 per A, providing velocities with a median uncertainty of 6 km s -1 . The primary focus of this paper is the determination of mean cluster metallicities, ages, and reddenings. Metallicities were estimated using a calibration of Lick indices with [Fe/H] provided by Galactic GCs. These match well the metallicities of 24 M31 clusters determined from Hubble Space Telescope color-magnitude diagrams, the differences having an rms of 0.2 dex. The metallicity distribution is not generally bimodal, in strong distinction with the bimodal Galactic globular distribution. Rather, the M31 distribution shows a broad peak, centered at [Fe/H] = -1, possibly with minor peaks at [Fe/H] = -1.4, -0.7, and -0.2, suggesting that the cluster systems of M31 and the Milky Way had different formation histories. Ages for clusters with [Fe/H] > - 1 were determined using the automatic stellar population analysis program EZ A ges. We find no evidence for massive clusters in M31 with intermediate ages, those between 2 and 6 Gyr. Moreover, we find that the mean ages of the old GCs are remarkably constant over about a decade in metallicity (-0.95∼< [Fe/H] ∼<0.0).

  14. Effects of Strain Rate on Compressive Properties in Bimodal 7075 Al-SiCp Composite

    Science.gov (United States)

    Lee, Hyungsoo; Choi, Jin Hyeok; Jo, Min Chul; Jo, Ilguk; Lee, Sang-Kwan; Lee, Sunghak

    2018-03-01

    A 7075 Al alloy matrix composite reinforced with SiC particulates (SiCps) whose sizes were 10 and 30 μm, i.e., a bimodal Al-SiCp composite, was made by a liquid pressing process, and its quasi-static and dynamic compressive properties were evaluated by using a universal testing machine and a split Hopkinson pressure bar, respectively. Mg-Si-, Al-Fe-, and Cu-rich intermetallic compounds existed inside the Al matrix, but might not deteriorate compressive properties because of their low volume fraction (about 2.6%) which was much lower than that of SiCp. The dynamic compressive strength was higher than the quasi-static strength, and was higher in the specimen tested at 2800 s-1 than in the specimen tested at 1400 s-1 according to the strain-rate hardening. For explaining the strain data, the blocking extent of crack propagation by the Al matrix was quantitatively examined. The melting of Al matrix occurred by adiabatic heating was favorable for the improvement in compressive strain because it favorably worked for activating the shear band formation and for blocking the crack propagation, thereby leading to the excellent compressive strain (10.9-11.6%) as well as maximum compressive strength (1057-1147 MPa). Thus, the present bimodal 7075 Al-SiCp composite provides a promise for new applications to high-performance armor plates.

  15. Bimodal mortality dynamics for uveal melanoma: a cue for metastasis development traits?

    International Nuclear Information System (INIS)

    Demicheli, Romano; Fornili, Marco; Biganzoli, Elia

    2014-01-01

    The study estimates mortality dynamics (event-specific hazard rates over a follow-up time interval) for uveal melanoma. Three thousands six hundred seventy two patients undergoing radical or conservative treatment for unilateral uveal melanoma, whose yearly follow-up data were reported in three published datasets, were analysed. Mortality dynamics was studied by estimating with the life-table method the discrete hazard rate for death. Smoothed curves were obtained by a Kernel-like smoothing procedure and a piecewise exponential regression model. The ratio deaths/patients at risk per year was the main outcome measure. The three explored hazard rate curves display a common bimodal pattern, with a sudden increase peaking at about three years, followed by reduction until the sixth-seventh year and a second surge peaking at about nine years after treatment. The bimodal pattern of mortality indicates that uveal melanoma metastatic development cannot be explained by a continuous growth model. Similar metastasis dynamics have been reported for other tumours, including early breast cancer, for which it supported a paradigm shift to an interrupted growth model, the implications of which are episodes of ‘tumour dormancy’. We propose that the concepts of tumour homeostasis, tumour dormancy and enhancement of metastasis growth related to primary tumour removal, convincingly explaining the clinical behaviour of breast cancer, may be used for uveal melanoma as well. To confirm this proposition, a careful analysis of uveal melanoma metastasis dynamics is strongly warranted

  16. Investigation of mixed fluorinated and triblock copolymer liquid crystals: imprint for mesostructured bimodal silica.

    Science.gov (United States)

    Assaker, Karine; Naboulsi, Issam; Stébé, Marie-José; Emo, Mélanie; Blin, Jean-Luc

    2015-05-15

    Due to the difference in «mutual phobicity» between fluorocarbon and hydrocarbon chains, mixtures of fluorinated and hydrogenated surfactants are excellent candidates to design bimodal systems having two types of mesopores. In literature, only a few papers deal with these bimodal systems. Here hexagonal liquid crystal mixtures of the polyoxyethylene fluoroalkyl ether [R(F)8(EO)9] and the Pluronic [P123] have been used to template this kind of mesostructure through the liquid crystal mechanism, which is barely considered. After the detailed investigation of the R(F)8(EO)9/P123/water liquid crystal domain, materials have been synthesized and characterized by small angle X-ray scattering, transmission electron microscopy and nitrogen adsorption-desorption analysis. Our results show that this system provides two separate pore sizes in the materials over the mesoporous range. The ratio between the small mesopores and the large ones depends on the proportion between the porogens in the mixture. Nonetheless, we also outline that a minimum quantity of silica is required to recover the two hexagonal networks. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Preparation of bimodal grain size 7075 aviation aluminum alloys and their corrosion properties

    Directory of Open Access Journals (Sweden)

    Wenming TIAN

    2017-10-01

    Full Text Available The bimodal grain size metals show improved strength and ductility compared to traditional metals; however, their corrosion properties are unknown. In order to evaluate the corrosion properties of these metals, the bimodal grain size 7075 aviation aluminum alloys containing different ratios of coarse (100 μm in diameter and fine (10 μm in diameter grains were prepared by spark plasma sintering (SPS. The effects of grain size as well as the mixture degree of coarse and fine grains on general corrosion were estimated by immersion tests, electrochemical measurements and complementary techniques such as scanning electron microscope (SEM and transmission electron microscope-energy disperse spectroscopy (TEM-EDS. The results show that, compared to fine grains, the coarse grains have a faster dissolution rate in acidic NaCl solution due to the bigger size, higher alloying elements content and larger area fraction of second phases in them. In coarse grains, the hydrogen ions have a faster reduction rate on cathodic second phases, therefore promoting the corrosion propagation. The mixture of coarse and fine grains also increases the electrochemical heterogeneity of alloys in micro-scale, and thus the increased mixture degree of these grains in metal matrix accelerates the corrosion rate of alloys in acidic NaCl solution.

  18. Bilingualism alters brain functional connectivity between "control" regions and "language" regions: Evidence from bimodal bilinguals.

    Science.gov (United States)

    Li, Le; Abutalebi, Jubin; Zou, Lijuan; Yan, Xin; Liu, Lanfang; Feng, Xiaoxia; Wang, Ruiming; Guo, Taomei; Ding, Guosheng

    2015-05-01

    Previous neuroimaging studies have revealed that bilingualism induces both structural and functional neuroplasticity in the dorsal anterior cingulate cortex (dACC) and the left caudate nucleus (LCN), both of which are associated with cognitive control. Since these "control" regions should work together with other language regions during language processing, we hypothesized that bilingualism may also alter the functional interaction between the dACC/LCN and language regions. Here we tested this hypothesis by exploring the functional connectivity (FC) in bimodal bilinguals and monolinguals using functional MRI when they either performed a picture naming task with spoken language or were in resting state. We found that for bimodal bilinguals who use spoken and sign languages, the FC of the dACC with regions involved in spoken language (e.g. the left superior temporal gyrus) was stronger in performing the task, but weaker in the resting state as compared to monolinguals. For the LCN, its intrinsic FC with sign language regions including the left inferior temporo-occipital part and right inferior and superior parietal lobules was increased in the bilinguals. These results demonstrate that bilingual experience may alter the brain functional interaction between "control" regions and "language" regions. For different control regions, the FC alters in different ways. The findings also deepen our understanding of the functional roles of the dACC and LCN in language processing. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Human Exploration Mission Capabilities to the Moon, Mars, and Near Earth Asteroids Using ''Bimodal'' NTR Propulsion

    International Nuclear Information System (INIS)

    Stanley K. Borowski; Leonard A. Dudzinski; Melissa L. McGuire

    2000-01-01

    The nuclear thermal rocket (NTR) is one of the leading propulsion options for future human exploration missions because of its high specific impulse (Isp ∼ 850 to 1000 s) and attractive engine thrust-to-weight ratio (∼ 3 to 10). Because only a minuscule amount of enriched 235 U fuel is consumed in an NRT during the primary propulsion maneuvers of a typical Mars mission, engines configured both for propulsive thrust and modest power generation (referred to as 'bimodal' operation) provide the basis for a robust, power-rich stage with efficient propulsive capture capability at the moon and near-earth asteroids (NEAs), where aerobraking cannot be utilized. A family of modular bimodal NTR (BNTR) space transfer vehicles utilize a common core stage powered by three ∼15-klb f engines that produce 50 kW(electric) of total electrical power for crew life support, high data rate communications with Earth, and an active refrigeration system for long-term, zero-boiloff liquid hydrogen (LH 2 ) storage. This paper describes details of BNTR engines and designs of vehicles using them for various missions

  20. Rotational multispectral fluorescence lifetime imaging and intravascular ultrasound: bimodal system for intravascular applications

    Science.gov (United States)

    Ma, Dinglong; Bec, Julien; Yankelevich, Diego R.; Gorpas, Dimitris; Fatakdawala, Hussain; Marcu, Laura

    2014-06-01

    We report the development and validation of a hybrid intravascular diagnostic system combining multispectral fluorescence lifetime imaging (FLIm) and intravascular ultrasound (IVUS) for cardiovascular imaging applications. A prototype FLIm system based on fluorescence pulse sampling technique providing information on artery biochemical composition was integrated with a commercial IVUS system providing information on artery morphology. A customized 3-Fr bimodal catheter combining a rotational side-view fiberoptic and a 40-MHz IVUS transducer was constructed for sequential helical scanning (rotation and pullback) of tubular structures. Validation of this bimodal approach was conducted in pig heart coronary arteries. Spatial resolution, fluorescence detection efficiency, pulse broadening effect, and lifetime measurement variability of the FLIm system were systematically evaluated. Current results show that this system is capable of temporarily resolving the fluorescence emission simultaneously in multiple spectral channels in a single pullback sequence. Accurate measurements of fluorescence decay characteristics from arterial segments can be obtained rapidly (e.g., 20 mm in 5 s), and accurate co-registration of fluorescence and ultrasound features can be achieved. The current finding demonstrates the compatibility of FLIm instrumentation with in vivo clinical investigations and its potential to complement conventional IVUS during catheterization procedures.

  1. Efficient and reusable polyamide-56 nanofiber/nets membrane with bimodal structures for air filtration.

    Science.gov (United States)

    Liu, Bowen; Zhang, Shichao; Wang, Xueli; Yu, Jianyong; Ding, Bin

    2015-11-01

    Nanofibrous media that both possess high airborne particle interception efficiency and robust air permeability would have broad technological implications for areas ranging from individual protection and industrial security to environmental governance; however, creating such filtration media has proved extremely challenging. Here we report a strategy to construct the bio-based polyamide-56 nanofiber/nets (PA-56 NFN) membranes with bimodal structures for effective air filtration via one-step electrospinning/netting. The PA-56 membranes are composed of completely covered two-dimensional (2D) ultrathin (∼20 nm) nanonets which are optimized by facilely regulating the solution concentration, and the bonded scaffold fibers constructed cavity structures which are synchronously created by using the CH3COOH inspiration. With integrated properties of small aperture, high porosity, and bonded scaffold, the resulting PA-56 NFN membranes exhibit high filtration efficiency of 99.995%, low pressure drop of 111 Pa, combined with large dust holding capacity of 49 g/m(2) and dust-cleaning regeneration ability, for filtrating ultrafine airborne particles in the most safe manner involving sieving principle and surface filtration. The successful synthesis of PA-56 NFN medium would not only make it a promising candidate for air filtration, but also provide new insights into the design and development of nanonet-based bimodal structures for various applications. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Human fatigue expression recognition through image-based dynamic multi-information and bimodal deep learning

    Science.gov (United States)

    Zhao, Lei; Wang, Zengcai; Wang, Xiaojin; Qi, Yazhou; Liu, Qing; Zhang, Guoxin

    2016-09-01

    Human fatigue is an important cause of traffic accidents. To improve the safety of transportation, we propose, in this paper, a framework for fatigue expression recognition using image-based facial dynamic multi-information and a bimodal deep neural network. First, the landmark of face region and the texture of eye region, which complement each other in fatigue expression recognition, are extracted from facial image sequences captured by a single camera. Then, two stacked autoencoder neural networks are trained for landmark and texture, respectively. Finally, the two trained neural networks are combined by learning a joint layer on top of them to construct a bimodal deep neural network. The model can be used to extract a unified representation that fuses landmark and texture modalities together and classify fatigue expressions accurately. The proposed system is tested on a human fatigue dataset obtained from an actual driving environment. The experimental results demonstrate that the proposed method performs stably and robustly, and that the average accuracy achieves 96.2%.

  3. Chemical Composition, Seasonal Variation and Size distribution of Atmospheric Aerosols at an Alpine Site in Guanzhong Plain, China

    Science.gov (United States)

    Li, J.

    2015-12-01

    PM10 and size-segregated aerosol samples were collected at Mt. Hua (2065 a.s.m) in central China, and determined for carbonaceous fraction, ions and organic composition. The concentration of most chemical compositions in summer are lower than those in winter, due to decreased emissions of biomass and coal burning for house heating. High temperature and relative humidity (RH) conditions are favorable for secondary aerosol formation, resulting in higher concentrations of SO42- and NH4+ in summer. Non-dehydrated sugars are increased in summer because of the enhanced metabolism. Carbon preference index results indicate that n-alkanes at Mt. Hua are derived mostly by plant wax. Low Benzo(a)pyrene/Benzo(a)pyrene ratios indicate that mountain aerosols are more aged. Concentrations of biogenic (BSOA, the isoprene/pinene/caryophyllene oxidation products) and anthropogenic (ASOA, mainly aromatic acids) SOA positively correlated with temperature . However, a decreasing trend of BSOA concentration with an increase in RH was observed during the sampling period, although a clear trend between ASOA and RH was not found. Based on the AIM Model calculation, we found that during the sampling period an increase in RH resulted in a decrease in the aerosol acidity and thus reduced the effect of acid-catalysis on BSOA formation. Size distributions of K+ and NH4+ present as an accumulation mode, in contrast to Ca2+ and Mg2+, which are mainly existed in coarse particles. SO42- and NO3- show a bimodal pattern. Dehydrated sugars, fossil fuel derived n-alkanes and PAHs presented unimode size distribution, whereas non-dehydrated sugars and plant wax derived n-alkanes showed bimodal pattern. Most of the determined BSOA are formed in the aerosol phase and enriched in the fine mode except for cis-pinonic acid, which is formed in the gas phase and subsequently partitioned into aerosol phase and thus presents a bimodal pattern with a major peak in the coarse mode.

  4. Time-slice maps showing age, distribution, and style of deformation in Alaska north of 60° N.

    Science.gov (United States)

    Moore, Thomas E.; Box, Stephen E.

    2016-08-29

    The structural architecture of Alaska is the product of a complex history of tectonism that occurred along the Cordilleran and Arctic margins of North America through interactions with ancient and modern ocean plates and with continental elements derived from Laurentia, Siberia, and Baltica. To unravel the tectonic history of Alaska, we constructed maps showing the age, distribution, structural style, and kinematics of contractional and penetrative extensional deformation in Alaska north of latitude 60° N. at a scale of 1:5,000,000. These maps use the Geologic Map of the Arctic (Harrison and others, 2011) as a base map and follow the guidelines in the Tectonic Map of the Arctic project (Petrov and others, 2013) for construction, including use of the International Commission on Stratigraphy time scale (Cohen and others, 2013) divided into 20 time intervals. We find evidence for deformation in 14 of the 20 time intervals and present maps showing the known or probable extent of deformation for each time interval. Maps and descriptions of deformational style, age constraints, kinematics, and information sources for each deformational episode are discussed in the text and are reported in tabular form. This report also contains maps showing the lithologies and structural geology of Alaska, a terrane map, and the distribution of tectonically important units including post-tectonic sedimentary basins, accretionary complexes, ophiolites, metamorphic rocks.These new maps show that most deformational belts in Alaska are relatively young features, having developed during the late Mesozoic and Cenozoic. The oldest episode of deformation recognized anywhere in Alaska is found in the basement of the Farewell terrane (~1.75 Ga). Paleozoic and early Mesozoic deformational events, including Devonian deformation in the Arctic Alaska terrane, Pennsylvanian deformation in the Alexander terrane, Permian deformation in the Yukon Composite (Klondike orogeny) and Farewell terranes (Browns

  5. Bimodal Long-lasting Components in Short Gamma-Ray Bursts: Promising Electromagnetic Counterparts to Neutron Star Binary Mergers

    Energy Technology Data Exchange (ETDEWEB)

    Kisaka, Shota; Sakamoto, Takanori [Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara, Kanagawa, 252-5258 (Japan); Ioka, Kunihito, E-mail: kisaka@phys.aoyama.ac.jp, E-mail: tsakamoto@phys.aoyama.ac.jp, E-mail: kunihito.ioka@yukawa.kyoto-u.ac.jp [Center for Gravitational Physics, Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)

    2017-09-10

    Long-lasting emission of short gamma-ray bursts (GRBs) is crucial to reveal the physical origin of the central engine as well as to detect electromagnetic (EM) counterparts to gravitational waves (GWs) from neutron star binary mergers. We investigate 65 X-ray light curves of short GRBs, which is six times more than previous studies, by combining both Swift /BAT and XRT data. The light curves are found to consist of two distinct components at >5 σ with bimodal distributions of luminosity and duration, i.e., extended (with a timescale of ≲10{sup 3} s) and plateau emission (with a timescale of ≳10{sup 3} s), which are likely the central engine activities, but not afterglows. The extended emission has an isotropic energy comparable to the prompt emission, while the plateau emission has ∼0.01–1 times this energy. Half (50%) of our sample has both components, while the other half is consistent with having both components. This leads us to conjecture that almost all short GRBs have both the extended and plateau emission. The long-lasting emission can be explained by the jets from black holes with fallback ejecta, and could power macronovae (or kilonovae) like GRB 130603B and GRB 160821B. Based on the observed properties, we quantify the detectability of EM counterparts to GWs, including the plateau emission scattered to the off-axis angle, with CALET /HXM, INTEGRAL /SPI-ACS, Fermi /GBM, MAXI /GSC, Swift /BAT, XRT, the future ISS-Lobster /WFI, Einstein Probe /WXT, and eROSITA .

  6. Slab break-off triggered lithosphere - asthenosphere interaction at a convergent margin: The Neoproterozoic bimodal magmatism in NW India

    Science.gov (United States)

    Wang, Wei; Pandit, Manoj K.; Zhao, Jun-Hong; Chen, Wei-Terry; Zheng, Jian-Ping

    2018-01-01

    The Neoproterozoic Malani Igneous Suite (MIS) is described as the largest felsic igneous province in India. The linearly distributed Sindreth and Punagarh basins located along eastern margin of this province represent the only site of bimodal volcanism and associated clastic sediments within the MIS. The in-situ zircon U-Pb dating by LA-ICPMS reveals that the Sindreth rhyolites were erupted at 769-762 Ma. Basaltic rocks from both the basins show distinct geochemical signatures that suggest an E-MORB source for Punagarh basalts (low Ti/V ratios of 40.9-28.2) and an OIB source (high Ti/V ratios of 285-47.6) for Sindreth basalts. In the absence of any evidence of notable crustal contamination, these features indicate heterogeneous mantle sources for them. The low (La/Yb)CN (9.34-2.10) and Sm/Yb (2.88-1.08) ratios of Punagarh basalts suggest a spinel facies, relatively shallow level mantle source as compared to a deeper source for Sindreth basalts, as suggested by high (La/Yb)CN (7.24-5.24) and Sm/Yb (2.79-2.13) ratios. Decompression melting of an upwelling sub-slab asthenosphere through slab window seems to be the most plausible mechanism to explain the geochemical characteristics. Besides, the associated felsic volcanics show A2-type granite signatures, such as high Y/Nb (5.97-1.55) and Yb/Ta (9.36-2.57) ratios, consistent with magma derived from continental crust that has been through a cycle of continent-continent collision or an island-arc setting. A localized extension within an overall convergent scenario is interpreted for Sindreth and Punagarh volcanics. This general convergent setting is consistent with the previously proposed Andean-type continental margin for NW Indian block, the Seychelles and Madagascar, all of which lay either at the periphery of Rodinia supercontinent or slightly off the Supercontinent.

  7. Android Fat Distribution Affects Some Hemostatic Parameters In Women With Polycystic Ovary Syndrome Compared With Healthy Control Subjects Matched For Age And Body Mass Index.

    OpenAIRE

    de Mendonça-Louzeiro, Maria Raquel Marques Furtado; Annichino-Bizzacchi, Joyce Maria; Benetti-Pinto, Cristina Laguna

    2016-01-01

    Objective: To correlate hemostatic parameters with clinical markers of fat distribution and laboratory variables in women with polycystic ovary syndrome (PCOS) compared with healthy control subjects. Design: Cross-sectional study. Setting: Tertiary teaching hospital. Patient(s): Forty-five women with PCOS and 45 control women matched for age and body mass index (BMI). Intervention(s): Clinical evaluation and venipuncture. Main Outcome Measure(s): Age, BMI, waist circumference (WC), hip circum...

  8. [Quantitative and spatial analysis in image processing: study of drusen distribution from the foveal center in age-related macular degeneration].

    Science.gov (United States)

    Barthes, A; Conrath, J; Ridings, B

    2005-03-01

    Angiofluorograms were obtained from 58 patients presenting posterior pole drusen due to age-related macular degeneration. These frames underwent image processing by morphological mathematics algorithms. The detection sensitivity of this algorithm is 78%. We present a quantitative and spatial analysis of drusen distribution from the foveal center in the form of a graph. This technique may allow for multi-date comparisons, by using a graphic representation of this risk factor for age-related macular degeneration.

  9. Brain regional distributions of the minor and trace elements, Na, Mg, Cl, K, Mn, Zn, Rb and Br, in young and aged mice

    International Nuclear Information System (INIS)

    Amano, R.; Oishi, S.; Ishie, M.; Kimura, M.

    2001-01-01

    Brain regional cerebral concentrations of minor and trace elements, Na, Mg, Cl, K, Mn, Zn, Rb and Br were determined in young and aged mice, by instrumental neutron activation analysis for small amounts of regional (corpus striatum, cerebellum, cerebral cortex, hippocampus, midbrain, pons and medulla olfactory bulb) samples. Significant age-related differences were found for Mn concentration in all brain regions: The Mn concentration of the young brain was higher than those of aged brain, in addition, Zn was distributed heterogeneously, and highly concentrated in cerebral cortex and hippocampus regions in both young and aged mice. These results suggest that, in the aged brain, Mn is required less than in the young brain, on the other hand, Zn is required equally in both young and aged brains. (author)

  10. Distribution of total serum IgE and specific IgE to common aeroallergens by sex and age, and their relationship to each other in a random sample of the Dutch general population aged 20-70 years

    NARCIS (Netherlands)

    Kerkhof, M; Droste, JHJ; deMonchy, JGR; Schouten, JP; Rijcken, B

    1996-01-01

    To describe the distribution of serum total IgE and specific IgE to common aeroallergens by sex and age and to study their relationship to each other, we measured serum total IgE and specific IgE (CAP) to house-dust mile, timothy grass, cat, birch, and Cladosporium in a random sample of 2496

  11. Integrated Analysis and Visualization of Group Differences in Structural and Functional Brain Connectivity: Applications in Typical Ageing and Schizophrenia.

    Directory of Open Access Journals (Sweden)

    Carolyn D Langen

    Full Text Available Structural and functional brain connectivity are increasingly used to identify and analyze group differences in studies of brain disease. This study presents methods to analyze uni- and bi-modal brain connectivity and evaluate their ability to identify differences. Novel visualizations of significantly different connections comparing multiple metrics are presented. On the global level, "bi-modal comparison plots" show the distribution of uni- and bi-modal group differences and the relationship between structure and function. Differences between brain lobes are visualized using "worm plots". Group differences in connections are examined with an existing visualization, the "connectogram". These visualizations were evaluated in two proof-of-concept studies: (1 middle-aged versus elderly subjects; and (2 patients with schizophrenia versus controls. Each included two measures derived from diffusion weighted images and two from functional magnetic resonance images. The structural measures were minimum cost path between two anatomical regions according to the "Statistical Analysis of Minimum cost path based Structural Connectivity" method and the average fractional anisotropy along the fiber. The functional measures were Pearson's correlation and partial correlation of mean regional time series. The relationship between structure and function was similar in both studies. Uni-modal group differences varied greatly between connectivity types. Group differences were identified in both studies globally, within brain lobes and between regions. In the aging study, minimum cost path was highly effective in identifying group differences on all levels; fractional anisotropy and mean correlation showed smaller differences on the brain lobe and regional levels. In the schizophrenia study, minimum cost path and fractional anisotropy showed differences on the global level and within brain lobes; mean correlation showed small differences on the lobe level. Only

  12. A Modern Analog to the Depositional Age Problem: Zircon and Apatite Fission Track and U-Pb Age Distributions by LA-ICP-MS

    Science.gov (United States)

    Donelick, H. M.; Donelick, M. B.; Donelick, R. A.

    2012-12-01

    Sand from three river systems in North Idaho (Snake River near Lewiston, Clearwater River near Lewiston and the Salmon River near White Bird) and two regional ash fall events (Mt. Mazama and Mt. St. Helens) were collected for zircon U-Pb detrital age analysis. Up to 120 grains of zircon per sample were ablated using a Resonetics M-50 193 nm ArF Excimer laser ablation (LA) system and the Pb, Th, and U isotopic signals were quantified using an Agilent 7700x quadrupole inductively coupled plasma-mass spectrometer (ICP-MS). Isotopic signals for major, minor, and trace elements, including all REEs, were also monitored. The youngest zircon U-Pb ages from the river samples were approximately 44 Ma; Cenozoic Idaho Batholith and Precambrian Belt Supergroup ages were well represented. Significant common Pb contamination of the Clearwater River sample (e.g., placer native Cu was observed in the sample) precluded detailed analysis of the zircon U-Pb ages but no interpretable ages Mazama 7,700 years ago, and no doubt other events during the Quaternary. Work currently in progress seeks to address bias against near 0 Ma ages in the catchment areas due to: a) small, local ash fall grain sizes and b) overwhelming number of older grains relative to the ash fall grains. Data from Mt. St. Helens ash from several localities near the mountain (Toutle River and Maple Flats, WA) and several far from the mountain (Spokane, WA; Princeton, ID; Kalispell, MT) and Mt. Mazama ash fall deposits near Lewiston, ID and Spokane, WA will be presented to address these possibilities. Additionally, fission track and U-Pb ages from apatites collected from these river and ash fall samples will also be shown to help constrain the problem.

  13. Deformation Behavior of Ultra-Strong and Ductile Mg-Gd-Y-Zn-Zr Alloy with Bimodal Microstructure

    Science.gov (United States)

    Xu, C.; Fan, G. H.; Nakata, T.; Liang, X.; Chi, Y. Q.; Qiao, X. G.; Cao, G. J.; Zhang, T. T.; Huang, M.; Miao, K. S.; Zheng, M. Y.; Kamado, S.; Xie, H. L.

    2018-02-01

    An ultra-strong and ductile Mg-8.2Gd-3.8Y-1Zn-0.4Zr (wt pct) alloy was developed by using hot extrusion to modify the microstructure via forced-air cooling and an artificial aging treatment. A superior strength-ductility balance was obtained that had a tensile yield strength of 466 MPa and an elongation to failure of 14.5 pct. The local strain evolution during the in situ testing of the ultra-strong and ductile alloy was quantitatively analyzed with high-resolution electron backscattered diffraction and digital image correlation. The fracture behavior during the tensile test was characterized by synchrotron X-ray tomography along with SEM and STEM observations. The alloy showed a bimodal microstructure, consisting of dynamically recrystallized (DRXed) grains with random orientations and elongated hot-worked grains with parallel to the extrusion direction. The DRXed grains were deformed by the basal slip and the hot-worked grains were deformed by the prismatic slip dominantly. The strain evolution analysis indicated that the multilayered structure relaxed the strain localization via strain transfer from the DRXed to the hot-worked regions, which led to the high ductility of the alloy. Precipitation of the γ' on basal planes and the β' phases on the prismatic planes of the α-Mg generated closed volumes, which enhanced the strength by pinning dislocations effectively, and contributed to the high ductility by impeding the propagation of micro-cracks inside the grains. The deformation incompatibility between the hot-worked grains and the arched block-shaped long-period stacking ordered (LPSO) phases induced the crack initiation and propagation, which fractured the alloy.

  14. U-Th age distribution of coral fragments from multiple rubble ridges within the Frankland Islands, Great Barrier Reef: Implications for past storminess history

    Science.gov (United States)

    Liu, Entao; Zhao, Jian-xin; Feng, Yue-xing; Leonard, Nicole D.; Clark, Tara R.; Roff, George

    2016-07-01

    Prograded coral rubble ridges have been widely used as archives for reconstructing long-term storm or storminess history. Chronologies of ridge systems in previous studies are often based on a limited number of low-resolution radiocarbon or optically-stimulated luminescence (OSL) ages per ridge (usually only one age per ridge), which carry intrinsic age uncertainties and make interpretation of storm histories problematic. To test the fidelity of storm ridges as palaeo-storm archives, we used high-precision U-Th dating to examine whether different samples from a single ridge are temporally constrained. We surveyed three transects of ridge systems from two continental islands (Normanby Island and High Island) within the Frankland Islands, Great Barrier Reef (GBR), and obtained 96 U-Th dates from coral rubble samples collected from within and between different ridges. Our results revealed significant differences in age ranges between the two islands. The steeper and more defined rubble ridges present on Normanby Island revealed that the majority of U-Th ages (over 60%) from a single ridge clustered within a narrow age range (∼100 years). By contrast, the lower and less defined ridges on High Island, which were more likely formed during both storm and non-storm high-energy events, revealed significant scatter in age distribution (>>200 years) with no notable clustering. The narrower age ranges obtained from the steeper and more defined rubble ridges suggest that previous approaches of using either limited samples from a single ridge or low-precision dating methods to establish chronologies are generally valid at centennial to millennial timescales, although caution must be taken to use such approaches for storm history reconstruction on shorter timescales (e.g. decadal). The correlation between U-Th mortality ages of coral rubble and historical stormy periods highlights the possibility of using coral rubble age distribution from rubble ridges to reconstruct the long

  15. Biennial pattern of rotavirus gastroenteritis in the Netherlands and a shifting age distribution following a low rotavirus season, 2010-2016.

    NARCIS (Netherlands)

    Verberk, J.D.M.; Pijnacker, R.; Bruijning-Verhagen, P.; Franz, E.; Vennema, H.; Hooiveld, M.; Hahné, S.J.M.; Melker, H.E. de

    2017-01-01

    A hyper-endemic rotavirus season was expected after a low-endemic 2014 season in the Netherlands. Rotavirus detections were however similar in 2015 and lower in 2016 compared with 2010-2013. Gastroenteritis consultations rates were also similar in 2015, but the age-distribution shifted to older

  16. Facile Synthesis of Gd-Cu-In-S/ZnS Bimodal Quantum Dots with Optimized Properties for Tumor Targeted Fluorescence/MR In Vivo Imaging.

    Science.gov (United States)

    Yang, Weitao; Guo, Weisheng; Gong, Xiaoqun; Zhang, Bingbo; Wang, Sheng; Chen, Na; Yang, Wentao; Tu, Yu; Fang, Xiangming; Chang, Jin

    2015-08-26

    Dual-modal imaging techniques have gained intense attention for their potential role in the dawning era of tumor early accurate diagnosis. Chelate-free robust dual-modal imaging nanoprobes with high efficiency and low toxicity are of essential importance for tumor targeted dual-modal in vivo imaging. It is still a crucial issue to endow Cd-free dual-modal nanoprobes with bright fluorescence as well as high relaxivity. Herein, a facile synthetic strategy was developed to prepare Gd-doped CuInS/ZnS bimodal quantum dots (GCIS/ZnS, BQDs) with optimized properties. The fluorescent properties of the GCIS/ZnS BQDs can be thoroughly optimized by varying reaction temperature, aging time, and ZnS coating. The amount of Gd precursor can be well-controlled to realize the optimized balance between the MR relaxivity and optical properties. The obtained hydrophobic GCIS/ZnS BQDs were surface engineered into aqueous phase with PEGylated dextran-stearyl acid polymeric lipid vesicles (PEG-DS PLVs). Upon the phase transfer, the hydrophilic GCIS/ZnS@PLVs exhibited pronounced near-infrared fluorescence as well as high longitudinal relaxivity (r1 = 9.45 mM(-1) S(-1)) in water with good colloidal stability. In vivo tumor-bearing animal experiments further verified GCIS/ZnS@PLVs could achieve tumor-targeted MR/fluorescence dual-modal imaging. No toxicity was observed in the in vivo and ex vivo experiments. The GCIS/ZnS@PLVs present great potential as bimodal imaging contrast agents for tumor diagnosis.

  17. Bimodal wireless sensing with dual-channel wide bandgap heterostructure varactors

    International Nuclear Information System (INIS)

    Deen, David A.; Osinsky, Andrei; Miller, Ross

    2014-01-01

    A capacitive wireless sensing scheme is developed that utilizes an AlN/GaN-based dual-channel varactor. The dual-channel heterostructure affords two capacitance plateaus within the capacitance-voltage (CV) characteristic, owing to the two parallel two-dimensional electron gases (2DEGs) located at respective AlN/GaN interfaces. The capacitance plateaus are leveraged for the definition of two resonant states of the sensor when implemented in an inductively-coupled resonant LRC network for wireless readout. The physics-based CV model is compared with published experimental results, which serve as a basis for the sensor embodiment. The bimodal resonant sensor is befitting for a broad application space ranging from gas, electrostatic, and piezoelectric sensors to biological and chemical detection

  18. Theoretical study of the frequency shift in bimodal FM-AFM by fractional calculus.

    Science.gov (United States)

    Herruzo, Elena T; Garcia, Ricardo

    2012-01-01

    Bimodal atomic force microscopy is a force-microscopy method that requires the simultaneous excitation of two eigenmodes of the cantilever. This method enables the simultaneous recording of several material properties and, at the same time, it also increases the sensitivity of the microscope. Here we apply fractional calculus to express the frequency shift of the second eigenmode in terms of the fractional derivative of the interaction force. We show that this approximation is valid for situations in which the amplitude of the first mode is larger than the length of scale of the force, corresponding to the most common experimental case. We also show that this approximation is valid for very different types of tip-surface forces such as the Lennard-Jones and Derjaguin-Muller-Toporov forces.

  19. Theoretical study of the frequency shift in bimodal FM-AFM by fractional calculus

    Directory of Open Access Journals (Sweden)

    Elena T. Herruzo

    2012-03-01

    Full Text Available Bimodal atomic force microscopy is a force-microscopy method that requires the simultaneous excitation of two eigenmodes of the cantilever. This method enables the simultaneous recording of several material properties and, at the same time, it also increases the sensitivity of the microscope. Here we apply fractional calculus to express the frequency shift of the second eigenmode in terms of the fractional derivative of the interaction force. We show that this approximation is valid for situations in which the amplitude of the first mode is larger than the length of scale of the force, corresponding to the most common experimental case. We also show that this approximation is valid for very different types of tip–surface forces such as the Lennard-Jones and Derjaguin–Muller–Toporov forces.

  20. Heatpipe power system and heatpipe bimodal system design and development options

    International Nuclear Information System (INIS)

    Houts, M.G.; Poston, D.I.; Emrich, W.J. Jr.

    1997-01-01

    The Heatpipe Power System (HPS) is a potential, near-term, low-cost space fission power system. The Heatpipe Bimodal System (HBS) is a potential, near-term, low-cost space fission power and/or propulsion system. Both systems will be composed of independent modules, and all components operate within the existing databases. The HPS and HBS have relatively few system integration issues; thus, the successful development of a module is a significant step toward verifying system feasibility and performance estimates. A prototypic HPS module is being fabricated, and testing is scheduled to begin in November 1996. A successful test will provide high confidence that the HPS can achieve its predicted performance

  1. Bimodal bilingualism as multisensory training?: Evidence for improved audiovisual speech perception after sign language exposure.

    Science.gov (United States)

    Williams, Joshua T; Darcy, Isabelle; Newman, Sharlene D

    2016-02-15

    The aim of the present study was to characterize effects of learning a sign language on the processing of a spoken language. Specifically, audiovisual phoneme comprehension was assessed before and after 13 weeks of sign language exposure. L2 ASL learners performed this task in the fMRI scanner. Results indicated that L2 American Sign Language (ASL) learners' behavioral classification of the speech sounds improved with time compared to hearing nonsigners. Results indicated increased activation in the supramarginal gyrus (SMG) after sign language exposure, which suggests concomitant increased phonological processing of speech. A multiple regression analysis indicated that learner's rating on co-sign speech use and lipreading ability was correlated with SMG activation. This pattern of results indicates that the increased use of mouthing and possibly lipreading during sign language acquisition may concurrently improve audiovisual speech processing in budding hearing bimodal bilinguals. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Bimodal Virtual Reality Stroop for Assessing Distractor Inhibition in Autism Spectrum Disorders.

    Science.gov (United States)

    Parsons, Thomas D; Carlew, Anne R

    2016-04-01

    Executive functioning deficits found in college students with ASD may have debilitating effects on their everyday activities. Although laboratory studies tend to report unimpaired inhibition in autism, studies of resistance to distractor inhibition reveal difficulties. In two studies, we compared a Virtual Classroom task with paper-and-pencil and computerized Stroop modalities in typically developing individuals and individuals with ASD. While significant differences were not observed between ASD and neurotypical groups on the paper-and-pencil and computerized task, individuals with ASD performed significantly worse on the virtual task with distractors. Findings suggest the potential of the Virtual Classroom Bimodal Stroop task to distinguish between prepotent response inhibition (non-distraction condition) and resistance to distractor inhibition (distraction condition) in adults with high functioning autism.

  3. Conventions for sign and speech transcription of child bimodal bilingual corpora in ELAN.

    Science.gov (United States)

    Chen Pichler, Deborah; Hochgesang, Julie A; Lillo-Martin, Diane; de Quadros, Ronice Müller

    2010-01-01

    This article extends current methodologies for the linguistic analysis of sign language acquisition to cases of bimodal bilingual acquisition. Using ELAN, we are transcribing longitudinal spontaneous production data from hearing children of Deaf parents who are learning either American Sign Language (ASL) and American English (AE), or Brazilian Sign Language (Libras, also referred to as Língua de Sinais Brasileira/LSB in some texts) and Brazilian Portuguese (BP). Our goal is to construct corpora that can be mined for a wide range of investigations on various topics in acquisition. Thus, it is important that we maintain consistency in transcription for both signed and spoken languages. This article documents our transcription conventions, including the principles behind our approach. Using this document, other researchers can chose to follow similar conventions or develop new ones using our suggestions as a starting point.

  4. Go big or die out: Bifurcation and bimodality in submarine sediment flow behaviour

    Science.gov (United States)

    Talling, P.; Paull, C. K.; Lintern, G.; Gwiazda, R.; Cartigny, M.; Hughes Clarke, J. E.; Xu, J.; Clare, M. A.; Parsons, D. R.; Simmons, S.; Maier, K. L.; Gales, J. A.; Hage, S.; McGann, M.; Pope, E.; Rosenberger, K. J.; Stacey, C.; Barry, J.; Lundsten, E. M.; Anderson, K.; O'Reilly, T. C.; Chapplow, N.; Vendettuoli, D.

    2017-12-01

    Submarine flows of sediment (turbidity currents) flush globally significant volumes of sediment and organic carbon into deep-sea basins. These flows create the largest sediment accumulations on Earth, which hold valuable oil and gas reserves. These flows affect global carbon burial, how deep-sea ecosystems function, and pose a hazard to offshore infrastructure. Only river systems transport such large amounts of sediment across such long distances. However, there are remarkably few direct measurements from active submarine flows, which is a stark contrast to >1 million direct observations from rivers. Here we present unusually detailed information on frequency, power and runout distance of multiple submarine flows at two contrasting locations. The first data set comes from Monterey Canyon, offshore California, which is fed by littoral cells. The second site is a river-fed delta in Bute Inlet, British Columbia. In both cases, the timing and runout distance of submarine flows was documented using instruments on multiple moorings placed along the 50-km long flow pathway. A striking observation is that flow behaviour and runout is strongly bimodal in both locations. Flows tend to either dissipate rapidly, or runout through the entire mooring arrays. We thus test whether i) the character of short or long runout flows can be distinguished at the first mooring and ii) whether long and short runout flows have different triggers. It has been proposed that submarine flows have two modes of behaviour; either eroding and accelerating, or depositing and dissipating. These field data support such a view of bifurcation and bimodality in flow behaviour. However, some short runout flows resemble their longer runout cousins at the first mooring, and there is no clear relationship between flow trigger and runout. Thus, some flows reach a point where their character is no longer dependent on their initial trigger or initial structure, but on factors acting along the flow pathway.

  5. Effect of Kerr-like medium on a two-level atom in interaction with bimodal oscillator

    Czech Academy of Sciences Publication Activity Database

    Abdalla, M. S.; Křepelka, Jaromír; Peřina, Jan

    2006-01-01

    Roč. 39, - (2006), s. 1563-1577 ISSN 0953-4075 R&D Projects: GA MŠk(CZ) OC P11.003 Institutional research plan: CEZ:AV0Z10100522 Keywords : kerr-like medium * two-level atom * bimodal oscillator Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.024, year: 2006

  6. AFSC/RACE/FBEP/Laurel: Effects of natural and anthropogenic disturbance on polychaete worm tubes and age-0 flatfish distribution

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is from a field experiment that examined how juvenile flatfish distribution changed with worm tube heterogeneity, i.e. density and patchiness.

  7. Bimodal stimulus timing-dependent plasticity in primary auditory cortex is altered after noise exposure with and without tinnitus.

    Science.gov (United States)

    Basura, Gregory J; Koehler, Seth D; Shore, Susan E

    2015-12-01

    Central auditory circuits are influenced by the somatosensory system, a relationship that may underlie tinnitus generation. In the guinea pig dorsal cochlear nucleus (DCN), pairing spinal trigeminal nucleus (Sp5) stimulation with tones at specific intervals and orders facilitated or suppressed subsequent tone-evoked neural responses, reflecting spike timing-dependent plasticity (STDP). Furthermore, after noise-induced tinnitus, bimodal responses in DCN were shifted from Hebbian to anti-Hebbian timing rules with less discrete temporal windows, suggesting a role for bimodal plasticity in tinnitus. Here, we aimed to determine if multisensory STDP principles like those in DCN also exist in primary auditory cortex (A1), and whether they change following noise-induced tinnitus. Tone-evoked and spontaneous neural responses were recorded before and 15 min after bimodal stimulation in which the intervals and orders of auditory-somatosensory stimuli were randomized. Tone-evoked and spontaneous firing rates were influenced by the interval and order of the bimodal stimuli, and in sham-controls Hebbian-like timing rules predominated as was seen in DCN. In noise-exposed animals with and without tinnitus, timing rules shifted away from those found in sham-controls to more anti-Hebbian rules. Only those animals with evidence of tinnitus showed increased spontaneous firing rates, a purported neurophysiological correlate of tinnitus in A1. Together, these findings suggest that bimodal plasticity is also evident in A1 following noise damage and may have implications for tinnitus generation and therapeutic intervention across the central auditory circuit. Copyright © 2015 the American Physiological Society.

  8. Evolution of carbon distribution and mechanical properties during the static strain ageing of heavily drawn pearlitic steel wires

    International Nuclear Information System (INIS)

    Lamontagne, A.; Massardier, V.; Sauvage, X.; Kléber, X.; Mari, D.

    2016-01-01

    The static strain ageing of heavily cold-drawn pearlitic steel wires was investigated using both global techniques and local techniques (Atom Probe Tomography (APT)), in order to highlight how the cold-drawn destabilized microstructure returns to a more stable state during post-drawing treatments between 20 °C and 150 °C. The global techniques (thermoelectric power, differential scanning calorimetry) clearly showed that ageing occurs in three successive ageing stages and is due to a redistribution of the carbon atoms coming from the strain-induced cementite dissolution. The first ageing stage was unambiguously attributed to the carbon segregation to the defects, while the second and third stages were interpreted as being due to the precipitation of intermediate carbides (2nd stage) and cementite (3rd stage). The true strain was not found to significantly affect the ageing kinetics and mechanisms but appeared to play a role in the amount of carbon atoms involved in the different ageing stages. APT analyses confirmed that ageing is governed by the carbon depletion of strain-induced supersaturated ferrite. The strengthening mechanisms associated with the different ageing stages were also discussed.

  9. Evolution of carbon distribution and mechanical properties during the static strain ageing of heavily drawn pearlitic steel wires

    Energy Technology Data Exchange (ETDEWEB)

    Lamontagne, A. [Univ Lyon, INSA Lyon, MATEIS – UMR CNRS 5510, Bât. St Exupéry, 25 Avenue Jean Capelle, F-69621 Villeurbanne Cedex (France); Massardier, V., E-mail: veronique.massardier@insa-lyon.fr [Univ Lyon, INSA Lyon, MATEIS – UMR CNRS 5510, Bât. St Exupéry, 25 Avenue Jean Capelle, F-69621 Villeurbanne Cedex (France); Sauvage, X. [University of Rouen, GPM, UMR CNRS 6634, BP 12, Avenue de l’Université, 76801 Saint-Etienne du Rouvray (France); Kléber, X. [Univ Lyon, INSA Lyon, MATEIS – UMR CNRS 5510, Bât. St Exupéry, 25 Avenue Jean Capelle, F-69621 Villeurbanne Cedex (France); Mari, D. [Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne, Station 3, Lausanne CH-1015 (Switzerland)

    2016-06-14

    The static strain ageing of heavily cold-drawn pearlitic steel wires was investigated using both global techniques and local techniques (Atom Probe Tomography (APT)), in order to highlight how the cold-drawn destabilized microstructure returns to a more stable state during post-drawing treatments between 20 °C and 150 °C. The global techniques (thermoelectric power, differential scanning calorimetry) clearly showed that ageing occurs in three successive ageing stages and is due to a redistribution of the carbon atoms coming from the strain-induced cementite dissolution. The first ageing stage was unambiguously attributed to the carbon segregation to the defects, while the second and third stages were interpreted as being due to the precipitation of intermediate carbides (2nd stage) and cementite (3rd stage). The true strain was not found to significantly affect the ageing kinetics and mechanisms but appeared to play a role in the amount of carbon atoms involved in the different ageing stages. APT analyses confirmed that ageing is governed by the carbon depletion of strain-induced supersaturated ferrite. The strengthening mechanisms associated with the different ageing stages were also discussed.

  10. A tight relation between the age distributions of stellar clusters and the properties of the interstellar medium in the host galaxy

    Science.gov (United States)

    Miholics, Meghan; Kruijssen, J. M. Diederik; Sills, Alison

    2017-09-01

    The age distributions of stellar cluster populations have long been proposed to probe the recent formation history of the host galaxy. However, progress is hampered by the limited understanding of cluster disruption by evaporation and tidal shocks. We study the age distributions of clusters in smoothed particle hydrodynamics simulations of isolated disc galaxies, which include a self-consistent, physical model for the formation and dynamical evolution of the cluster population and account for the variation of cluster disruption in time and space. We show that the downward slope of the cluster age distribution due to disruption cannot be reproduced with a single functional form, because the disruption rate exhibits systematic trends with cluster age (the 'cruel cradle effect'). This problem is resolved by using the median cluster age to trace cluster disruption. Across 120 independent galaxy snapshots and simulated cluster populations, we perform two-dimensional power-law fits of the median cluster age to various macroscopic physical quantities and find that it scales as t_med∝ Σ ^{-0.51± 0.03}σ _1D^{-0.85± 0.10}M_min^γ, for the gas surface density Σ, gas velocity dispersion σ1D, and minimum cluster mass Mmin. This scaling accurately describes observed cluster populations and indicates disruption by impulsive tidal shocks from the interstellar medium. The term M_min^γ provides a model-independent way to measure the mass dependence of the cluster disruption time γ. Finally, the ensemble-average cluster lifetime depends on the gas density less strongly than the instantaneous disruption time of single clusters. These results reflect the variation of cluster disruption in time and space. We provide quantitative ways of accounting for these physics in cluster population studies.

  11. Carbon concentrations and carbon pool distributions in dry, moist, and cold mid-aged forests of the Rocky Mountains

    Science.gov (United States)

    Theresa B. Jain; Russell T. Graham; David Adams

    2010-01-01

    Although "carbon” management may not be a primary objective in forest management, influencing the distribution, composition, growth, and development of biomass to fulfill multiple objectives is; therefore, given a changing climate, managing carbon could influence future management decisions. Also, typically, the conversion from total biomass to total carbon is 50...

  12. Influence of Cement Particle-Size Distribution on Early Age Autogenous Strains and Stresses in Cement-Based Materials

    DEFF Research Database (Denmark)

    Bentz, Dale P.; Jensen, Ole Mejlhede; Hansen, Kurt Kielsgaard

    2001-01-01

    The influence of cement particle-size distribution on autogenous strains and stresses in cement pastes of identical water-to-cement ratios is examined for cement powders of four different finenesses. Experimental measurements include chemical shrinkage, to quantify degree of hydration; internal r...

  13. Fetal and infant growth patterns associated with total and abdominal fat distribution in school-age children

    NARCIS (Netherlands)

    Gishti, O.; Gaillard, R.; Manniesing, R.; Abrahamse-Berkeveld, M.; Beek, E.M. van der; Heppe, D.H.M.; Steegers, E.A.P.; Hofman, A.; Duijts, L.; Durmus, B.u.; Jaddoe, V.W.

    2014-01-01

    Context: Higher infant growth rates are associated with an increased risk of obesity in later life. Objective: We examined the associations of longitudinally measured fetal and infant growth patterns with total and abdominal fat distribution in childhood. Design, Settings and participants:We

  14. Differences in the Distribution of Bi?fidobacterial and Enterobacterial Species in Human Faecal Microflora of Three Different (Children, Adults, Elderly) Age Groups

    OpenAIRE

    Gavini, Franҫoise; Cayuela, Chantal; Antoine, Jean-Michel; Lecoq, Catherine; Lefebvre, Bernard; Membré, Jeanne-Marie; Neut, Christel

    2011-01-01

    To determine if there is any change with age in the distribution of Bifidobacterium and Enterobacteriaceae species in human intestinal microflora, strains were isolated from a total of 54 samples of human faeces (15 children, 3–15 years old; 17 adults, 30–46 years old; 22 elderly, 69–89 years old). The bifidobacteria were identified at species level using a numerical phenotypic identification system developed on the Internet (http://kounou.lille.inra.fr) and DNA–DNA hy...

  15. Estimation of apolipoprotein E genotype-specific relative mortality risks from the distribution of genotypes in centenarians and middle-aged men

    DEFF Research Database (Denmark)

    Gerdes, U.; Jeune, Bernard; Andersen-Ranberg, Karen

    2000-01-01

    We developed a method to estimate genotype-specific average relative mortality risk, R, from genotype distributions in cross-sectional studies of people belonging to different age-groups, and applied the method to new data from a study of apolipoprotein E genotypes (apoE) in 177 Danish centenaria...... of this kind, they are more impressive and may propagate the misconception that apoE is a "longevity gene"....

  16. The Effect Of Two-Stage Age Hardening Treatment Combined With Shot Peening On Stress Distribution In The Surface Layer Of 7075 Aluminum Alloy

    Directory of Open Access Journals (Sweden)

    Kaczmarek Ł.

    2015-09-01

    Full Text Available The article present the results of the study on the improvement of mechanical properties of the surface layer of 7075 aluminum alloy via two-stage aging combined with shot peening. The experiments proved that thermo-mechanical treatment may significantly improve hardness and stress distribution in the surface layer. Compressive stresses of 226 MPa±5.5 MPa and hardness of 210±2 HV were obtained for selected samples.

  17. Prospective microglia and brain macrophage distribution pattern in normal rat brain shows age sensitive dispersal and stabilization with development.

    Science.gov (United States)

    Ghosh, Payel; Mukherjee, Nabanita; Ghosh, Krishnendu; Mallick, Suvadip; Pal, Chiranjib; Laskar, Aparna; Ghosh, Anirban

    2015-09-01

    The monocytic lineage cells in brain, generally speaking brain macrophage and/or microglia show some dissimilar distribution patterns and disagreement regarding their origin and onset in brain. Here, we investigated its onset and distribution/colonization pattern in normal brain with development. Primarily, early and late embryonic stages, neonate and adult brains were sectioned for routine H/E staining; a modified silver-gold staining was used for discriminating monocytic lineage cells in brain; and TEM to deliver ultramicroscopic details of these cells in brain. Immunofluorescence study with CD11b marker revealed the distribution of active microglia/macrophage like cells. Overall, in early embryonic day 12, the band of densely stained cells are found at the margin of developing ventricles and cells sprout from there dispersed towards the outer edge. However, with development, this band shrunk and the dispersion trend decreased. The deeply stained macrophage like cell population migration from outer cortex to ventricle observed highest in late embryonic days, continued with decreased amount in neonates and settled down in adult. In adult, a few blood borne macrophage like cells were observed through the vascular margins. TEM study depicted less distinguishable features of cells in brain in early embryo, whereas from late embryo to adult different neuroglial populations and microglia/macrophages showed distinctive features and organization in brain. CD11b expression showed some similarity, though not fully, with the distribution pattern depending on the differentiation/activation status of these macrophage lineage cells. This study provides some generalized spatial and temporal pattern of macrophage/microglia distribution in rat brain, and further indicates some intrigue areas that need to be addressed.

  18. 40Ar/39Ar geochronology, elemental and Sr-Nd-Pb isotope geochemistry of the Neogene bimodal volcanism in the Yükselen area, NW Konya (Central Anatolia, Turkey)

    Science.gov (United States)

    Gençoğlu Korkmaz, Gülin; Asan, Kürşad; Kurt, Hüseyin; Morgan, Ganerød

    2017-05-01

    Bimodal volcanic suites occur in both orogenic and anorogenic geotectonic settings. Although their formation can be attributed to either fractional crystallization from basaltic parents to felsic derivatives or partial melting of different sources, the origin of bimodal suites is still unclear. By reporting mineral chemistry, 40Ar/39Ar geochronology, elemental and Sr-Nd-Pb isotope geochemistry data, this study aims to investigate the genesis of bimodal basalt-dacite association from the Yükselen area located on the northern end of the Sulutas Volcanic Complex (Konya, Central Anatolia). The Yükselen area volcanic rocks are represented by basaltic lava flows, and dacitic dome with enclaves and pyroclastics. Basaltic flows and pyroclastic rocks are interlayered with the Neogene fluvio-lacustrine sedimentary units, while dacitic rocks cut the pre-Neogene basement in the area. A biotite separation from dacites yielded 40Ar/39Ar plateau age of 16.11 ± 0.18 Ma. On the other hand, a whole rock sample from basalts gave two plateau ages of 16.45 ± 0.76 Ma and 22.37 ± 0.65 Ma for the first steps and next steps, respectively. The investigated basalts are sodic alkaline, and characterized by ocean island basalt (OIB)-like anorogenic geochemical signatures. However, dacites are calc-alkaline and metaluminous, and carry geochemical signatures of orogenic adakites. Sr-Nd-Pb isotopic systematics suggest that the basalts were derived from an asthenospheric mantle source enriched by recycled crustal rocks. The dacites show more enriched Sr and Pb ratios and more depleted Nd ones relative to the basalts, which at the first glance might be attributed to crustal contamination of the associated basalts. However, trace element features of the dacites rule out cogenetic relationship between the two rock types, and point to an origin by melting of lower crust. On the other hand, enclaves share several elemental and isotopic characteristics with the dacites, and appear to be fragments

  19. Finite-thrust optimization of interplanetary transfers of space vehicle with bimodal nuclear thermal propulsion

    Science.gov (United States)

    Kharytonov, Oleksii M.; Kiforenko, Boris M.

    2011-08-01

    The nuclear thermal rocket (NTR) propulsion is one of the leading promising technologies for primary space propulsion for manned exploration of the solar system due to its high specific impulse capability and sufficiently high thrust-to-weight ratio. Another benefit of NTR is its possible bimodal design, when nuclear reactor is used for generation of a jet thrust in a high-thrust mode and (with an appropriate power conversion system) as a source of electric power to supply the payload and the electric engines in a low-thrust mode. The model of the NTR thrust control was developed considering high-thrust NTR as a propulsion system of limited power and exhaust velocity. For the proposed model the control of the thrust value is accomplished by the regulation of reactor thermal power and propellant mass flow rate. The problem of joint optimization of the combination of high- and low-thrust arcs and the parameters of bimodal NTR (BNTR) propulsion system is considered for the interplanetary transfers. The interplanetary trajectory of the space vehicle is formed by the high-thrust NTR burns, which define planet-centric maneuvers and by the low-thrust heliocentric arcs where the nuclear electric propulsion (NEP) is used. The high-thrust arcs are analyzed using finite-thrust approach. The motion of the corresponding dynamical system is realized in three phase spaces concerning the departure planet-centric maneuver by means of high-thrust NTR propulsion, the low-thrust NEP heliocentric maneuver and the approach high-thrust NTR planet-centric maneuver. The phase coordinates are related at the time instants of the change of the phase spaces due to the relations between the space vehicle masses. The optimal control analysis is performed using Pontryagin's maximum principle. The numerical results are analyzed for Earth-Mars "sprint" transfer. The optimal values of the parameters that define the masses of NTR and NEP subsystems have been evaluated. It is shown that the low

  20. Using groundwater age distributions to understand changes in methyl tert-butyl ether (MtBE) concentrations in ambient groundwater, northeastern United States

    Science.gov (United States)

    Lindsey, Bruce; Ayotte, Joseph; Jurgens, Bryant; DeSimone, Leslie

    2017-01-01

    Temporal changes in methyl tert-butyl ether (MtBE) concentrations in groundwater were evaluated in the northeastern United States, an area of the nation with widespread low-level detections of MtBE based on a national survey of wells selected to represent ambient conditions. MtBE use in the U.S. peaked in 1999 and was largely discontinued by 2007. Six well networks, each representing specific areas and well types (monitoring or supply wells), were each sampled at 10 year intervals between 1996 and 2012. Concentrations were decreasing or unchanged in most wells as of 2012, with the exception of a small number of wells where concentrations continue to increase. Statistically significant increasing concentrations were found in one network sampled for the second time shortly after the peak of MtBE use, and decreasing concentrations were found in two networks sampled for the second time about 10 years after the peak of MtBE use. Simulated concentrations from convolutions of estimates for concentrations of MtBE in recharge water with age distributions from environmental tracer data correctly predicted the direction of MtBE concentration changes in about 65 percent of individual wells. The best matches between simulated and observed concentrations were found when simulating recharge concentrations that followed the pattern of national MtBE use. Some observations were matched better when recharge was modeled as a plume moving past the well from a spill at one point in time. Modeling and sample results showed that wells with young median ages and narrow age distributions responded more quickly to changes in the contaminant source than wells with older median ages and broad age distributions. Well depth and aquifer type affect these responses. Regardless of the timing of decontamination, all of these aquifers show high susceptibility for contamination by a highly soluble, persistent constituent.

  1. Why do Galaxies Stop Forming Stars? New Evidence for the Role of AGN-feedback in Driving Galaxy Bimodality

    Science.gov (United States)

    Bluck, Asa; Teimoorinia, Hossen; Ellison, Sara L.; Mendel, Trevor

    2018-01-01

    One of the most striking features of the population of local galaxies is that the distributions of several key galaxy properties are highly bimodal (e.g. color and star formation rate). In general, high mass galaxies in dense environments, with bulge-dominated morphologies and pressure supported kinematics are more frequently passive (non-star forming) than lower mass galaxies in low density environments, with disc-dominated morphologies and rotationally supported kinematics. Understanding which, if any, of these correlations is causally related to the ‘quenching’ of star formation in galaxies remains an active and hotly debated area of investigation in modern astrophysics.Theoretically, a wealth of physical processes have been evoked to account for central galaxy quenching, including halo mass quenching from virial shocks, feedback from active galactic nuclei (AGN; in either the quasar or radio mode), stabilizing torques from central mass concentrations, feedback from supernovae, or even magnetic fields interacting with the hot gas halo.I will present strong new statistical evidence which suggests that the quenched fraction of local central galaxies is primarily related to their central kinematics (Bluck et al. 2016; 2017 in prep.). I will show that this is broadly consistent with quenching from AGN feedback, through a detailed comparison with a semi-analytic model and a cosmological hydrodynamical simulation.Using a sample of over half a million local galaxies from the SDSS DR7, we go on to develop a number of sophisticated techniques, including machine learning with artificial neural networks, to rank the importance of galaxy properties to quenching (Teimoorinia, Bluck & Ellison 2016). We find that properties closely correlated with the central supermassive black hole are highly favoured statistically to predict whether a galaxy will be star forming or not. Perhaps surprisingly, stellar mass and halo mass have no impact on star formation activity in central

  2. Drilling constraints on bimodal volcanism and subsequent formation of contrasted uppermost crustal compositions at the middle Okinawa Trough

    Science.gov (United States)

    Yamasaki, T.; Takaya, Y.; Mukae, N.; Nagase, T.; Tindell, T.; Totsuka, S.; Uno, Y.; Yonezu, K.; Nozaki, T.; Ishibashi, J. I.; Kumagai, H.; Maeda, L.; Shipboard Scientist, C.

    2016-12-01

    The Okinawa Trough (OT) is a young and actively spreading back-arc basin, extending behind the Ryukyu arc-trench system in the southeastern margin of the East China Sea. The OT is believed to be in an initial rifting stage (starting from 6-9 Ma), prior to the normal/stable seafloor spreading which constitutes the main stage of back-arc basin formation. Two drilling cruises ‒ the IODP Exp. 331 and SIP CK14-04 D/V Chikyu Cruise (Exp. 907) in 2010 and 2014 ‒ were conducted at the Iheya North Knoll, middle OT. The Iheya North Knoll is a domal volcanic complex consisting of small volcanic bodies. On these cruises, pumiceous gravel and altered rhyolitic rocks, as well as hemi-pelagic sediments, hydrothermal clay and Kuroko-type ores, were recovered from the upper 200 m of the crust. From Feb. 11, 2016 to Mar. 17, 2016, the SIP CK16-01 (Exp. 908) D/V Chikyu cruise was conducted at Iheya North Knoll and the sediment-covered rifting center of the Iheya-Minor Ridge area, middle OT. The Iheya-Minor ridge area is also an active hydrothermal field, located 25 km southeast of the Iheya North Knoll. In this area, basaltic rocks are widely distributed, and drilling has confirmed that the basaltic materials continue to 120 m below the seafloor. From an igneous petrological point of view, the volcanic rocks in the Okinawa Trough are characterized by bimodal basaltic and rhyolitic compositions, with a compositional gap between SiO2 = 56-66 wt%. The origin of the rhyolitic rock has been interpreted as magmatic differentiation of basaltic magma. However, the existence of an active basalt-hosted hydrothermal field in the Iheya-Minor ridge area suggests the presence of hot basaltic rocks at a shallow position in the crust, and reaching recharged seawater at this depth. Furthermore, the composition of felsic rocks just after the compositional gap (SiO2 = 67 wt%) is very similar to that of the minimum melt of a granitic system, and experimental partial melt of hydrous basalt. Therefore

  3. HIV Infection Is Associated with Increased Fatty Infiltration of the Thigh Muscle with Aging Independent of Fat Distribution.

    Directory of Open Access Journals (Sweden)

    Javzandulam Natsag

    Full Text Available Lower muscle density on computed tomography (CT provides a measure of fatty infiltration of muscle, an aspect of muscle quality that has been associated with metabolic abnormalities, weakness, decreased mobility, and increased fracture risk in older adults. We assessed the cross-sectional relationship between HIV serostatus, age, thigh muscle attenuation, and thigh muscle cross-sectional area (CSA.Mean CT-quantified Hounsfield units (HU of the thigh muscle bundle and CSA were evaluated in 368 HIV-infected and 145 HIV-uninfected men enrolled in the Multicenter AIDS Cohort Study (MACS Cardiovascular Substudy using multivariable linear regression. Models all were adjusted for HIV serostatus, age, race, and body mass index (BMI; each model was further adjusted for covariates that differed by HIV serostatus, including insulin resistance, hepatitis C, malignancy, smoking, alcohol use, and self-reported limitation in physical activity.HIV-infected men had greater thigh muscle CSA (p<0.001 but lower muscle density (p<0.001 compared to HIV-uninfected men. Muscle density remained lower in HIV-infected men (p = 0.001 when abdominal visceral adiposity, and thigh subcutaneous adipose tissue area were substituted for BMI in a multivariable model. Muscle density decreased by 0.16 HU per year (p<0.001 of increasing age among the HIV-infected men, but not in the HIV-uninfected men (HIV x age interaction -0.20 HU; p = 0.002.HIV-infected men had lower thigh muscle density compared to HIV-uninfected men, and a more pronounced decline with increasing age, indicative of greater fatty infiltration. These findings suggest that lower muscle quality among HIV-infected persons may be a risk factor for impairments in physical function with aging.

  4. [Application of the data from China Total Diet Study to assess the distribution of lead exposure in different age-gender population groups].

    Science.gov (United States)

    Li, Xiaowei; Liu, Qing; Liu, Liping; Wu, Yongning

    2012-05-01

    To assess the distribution of dietary lead exposure in different age-gender groups of Chinese residents by using the data from China Total Diet Study, and combining the new risk assessment and the PTWI withdrawn by JECFA. Methods Combining the lead concentrations of dietary samples with the food consumption data from China Total Diet Study in 2007 to obtain the distribution of dietary intake and dietary source of lead in different age-gender population groups. Dietary lead exposure of different age-gender population groups in China was in the range of 48.7 -116.7 microg/d. The status of higher lead exposure in younger age groups was not optimistic, as the mean and median margins of exposure (MOE) have been less than 1.0 (0.1 - 0.3). The main sources of dietary lead were cereals and vegetables, which covering 57% of total lead exposure. Lowering the dietary lead exposure of Chinese residents is necessary, especially of infants and children.

  5. Star distribution in the Orion spiral arm

    International Nuclear Information System (INIS)

    Basharina, T.S.; Pavlovskaya, E.D.; Filippova, A.A.

    1985-01-01

    The structure of the Orion spiral arm is studied by numerical experiments, assuming that in each direction considered the star distribution along the line of sight is a combination of two Gaussian laws. The corresponding parameters are evaluated for four Milky Way fields; the bimodal laws now fit the observations by the chi 2 criterion. In the Orion arm the line-of-sight star densities follow asymmetric curves, steeper at the outer edge of the arm

  6. The effect of age on distribution of skatole and indole levels in entire male pigs in four breeds: Yorkshire, Landrace, Hampshire and Duroc.

    Science.gov (United States)

    Babol, J; Zamaratskaia, G; Juneja, R K; Lundström, K

    2004-06-01

    High skatole and to a lesser degree indole levels in some entire male pigs result in occurrence of off-flavor in meat, called boar taint. In this study, plasma samples from 117 Yorkshire, 134 Landrace, 184 Hampshire and 75 Duroc entire male pigs collected at different ages were analyzed for skatole and slightly fewer samples for indole concentrations. For each breed, a distinct age-related distribution of plasma skatole levels was observed. Skatole levels were increased at approximately 180-200 days of age, reaching very high levels is some individuals. Afterwards, the levels decreased; in Yorkshire and Landrace at approximately 240-260 and in Hampshire and Duroc at 310-360 days of age. The decrease of skatole levels was also observed in samples collected from 15 Landrace boars at two different ages: 16.8 μg/L (SD=17.36) vs. 5.9 μg/L (SD=3.48, p=0.016) in samples taken at the mean age of 210 and 314 days, respectively. Indole levels showed similar age- and breed-related variations to skatole. At the time of increased skatole concentrations (age from 180 to 360 days, depending on breed) 25.5% of Yorkshire, 31.6% of Landrace, 20.3% of Hampshire and 61.1% of Duroc entire male pigs had skatole levels above 12.6 μg/L of plasma, which corresponds to the threshold level of 0.20 μg/g of fat that is used for selecting tainted carcasses. The results indicate that increased levels of skatole in entire male pigs are related to puberty and taking skatole measurements at that age could be advantageous when considering genetic selection to reduce boar taint level in entire male pigs. Breed differences should be also taken into account.

  7. Temporal distribution of autobiographical memory: uncovering the reminiscence bump in Japanese young and middle-aged adults

    NARCIS (Netherlands)

    Kawasaki, Y.; Janssen, S.M.J.; Inoue, T.

    2011-01-01

    The reminiscence bump is the effect that people recall more personal events from their teenage period than from adjacent lifetime periods. The effect is generally found in studies that divide the results of participants, who were at least 40 years old, into age bins of 10 years. In this study, the

  8. Inheritance of Properties of Normal and Non-Normal Distributions after Transformation of Scores to Ranks

    Science.gov (United States)

    Zimmerman, Donald W.

    2011-01-01

    This study investigated how population parameters representing heterogeneity of variance, skewness, kurtosis, bimodality, and outlier-proneness, drawn from normal and eleven non-normal distributions, also characterized the ranks corresponding to independent samples of scores. When the parameters of population distributions from which samples were…

  9. Role of Micro-Topographic Variability on the Distribution of Inorganic Soil-Nitrogen Age in Intensively Managed Landscape

    Science.gov (United States)

    Woo, Dong K.; Kumar, Praveen

    2017-10-01

    How does the variability of topography structure the spatial heterogeneity of nutrient dynamics? In particular, what role does micro-topographic depression play in the spatial and temporal dynamics of nitrate, ammonia, and ammonium? We explore these questions using the 3-D simulation of their joint dynamics of concentration and age. To explicitly resolve micro-topographic variability and its control on moisture, vegetation, and carbon-nitrogen dynamics, we use a high-resolution LiDAR data over an agricultural site under a corn-soybean rotation in the Intensively Managed landscapes Critical Zone Observatory in the U.S. Midwest. We utilize a hybrid CPU-GPU parallel computing architecture to reduce the computational cost associated with such high-resolution simulations. Our results show that in areas that present closed topographic depressions, relatively lower nitrate concentration and age are observed compared to elsewhere. The periodic ponding in depressions increases the downward flux of water that carries more dissolved nitrate to the deeper soil layer. However, the variability in the depressions is relatively higher as a result of the episodic ponding pattern. When aggregate efflux from the soil domain at the bottom of the soil is considered, we find a gradual decrease in the age on the rising limb of nitrate efflux and a gradual increase on the falling limb. In addition, the age of the nitrate efflux ranges from 4 to 7 years. These are significantly higher as compared to the ages associated with a nonreactive tracer indicating that they provide an inaccurate estimate of residence time of a reactive constituent through the soil column.

  10. Compressibility and tablet forming ability of bimodal granule mixtures: Experiments and DEM simulations.

    Science.gov (United States)

    Nordström, Josefina; Alderborn, Göran; Frenning, Göran

    2018-04-05

    Compressibility and tablet forming ability (compactibility) of bimodal mixtures of differently sized granules formed from microcrystalline cellulose were studied experimentally and numerically with the discrete element method (DEM). Compression data was analysed using the Kawakita equation. A multi-body contact law that accounts for contact dependence resulting from plastic incompressibility/geometric hardening was used in the DEM simulations. The experimental Kawakita a and 1/b parameters both depended non-monotonically on composition (weight fraction of large particles). For the a parameter, this dependence was explained by variations in the porosity of the initial granule beds; for the 1/b parameter, other factors were found to be of importance as well. The numerical results generally compared favourably with the experiments, demonstrating the usefulness of the DEM at high relative densities, provided that a suitable multi-particle contact model is used. For all mixtures, the tensile strength of the formed tablets increased with increasing applied pressure. The tensile strength generally decreased with increasing fraction of large particle, and this decrease was more rapid for large differences in particle size. A possible interpretation of these findings was proposed, in terms of differences in lateral support of small particles in the vicinity of large particles. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Far-from-Equilibrium Route to Superthermal Light in Bimodal Nanolasers

    Science.gov (United States)

    Marconi, Mathias; Javaloyes, Julien; Hamel, Philippe; Raineri, Fabrice; Levenson, Ariel; Yacomotti, Alejandro M.

    2018-02-01

    Microscale and nanoscale lasers inherently exhibit rich photon statistics due to complex light-matter interaction in a strong spontaneous emission noise background. It is well known that they may display superthermal fluctuations—photon superbunching—in specific situations due to either gain competition, leading to mode-switching instabilities, or carrier-carrier coupling in superradiant microcavities. Here we show a generic route to superbunching in bimodal nanolasers by preparing the system far from equilibrium through a parameter quench. We demonstrate, both theoretically and experimentally, that transient dynamics after a short-pump-pulse-induced quench leads to heavy-tailed superthermal statistics when projected onto the weak mode. We implement a simple experimental technique to access the probability density functions that further enables quantifying the distance from thermal equilibrium via the thermodynamic entropy. The universality of this mechanism relies on the far-from-equilibrium dynamical scenario, which can be mapped to a fast cooling process of a suspension of Brownian particles in a liquid. Our results open up new avenues to mold photon statistics in multimode optical systems and may constitute a test bed to investigate out-of-equilibrium thermodynamics using micro or nanocavity arrays.

  12. Bimodal pollination system of the bromeliad Aechmea nudicaulis involving hummingbirds and bees.

    Science.gov (United States)

    Schmid, S; Schmid, V S; Zillikens, A; Harter-Marques, B; Steiner, J

    2011-01-01

    In order to compare the effectiveness of birds and insects as pollinators, we studied the floral biology of the bromeliad Aechmea nudicaulis (L.) Grisebach in the biome of the Atlantic rain forest, southern Brazil. On Santa Catarina Island, flowering extends from mid-September to the end of December, with diurnal anthesis. The reproductive system is obligatory xenogamy, thus pollinator-dependent. Flowers secrete 31.84 μl of nectar per day, with a mean sugar concentration of 23.2%. Highest nectar volume and sugar concentration occur at the beginning of anthesis. Most floral traits are characteristic for ornithophily, and nectar production appears to be adapted to the energy demand of hummingbirds. Continued secretion of the sucrose-dominated nectar attracts and binds visitors to inflorescences, strengthening trapline foraging behaviour. Experiments assessing seed set after single flower visits were performed with the most frequent visitors, revealing the hummingbird Thalurania glaucopis as the most effective pollen vector. In addition, bees are also functional pollinators, as substantiated by their high visitation frequency. We conclude that this pollination system is bimodal. Thus, there is redundancy in the pollination service provided by birds and bees, granting a high probability of successful reproduction in Ae. nudicaulis. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.

  13. Sensitivity of bimodal listeners to interaural time differences with modulated single- and multiple-channel stimuli.

    Science.gov (United States)

    Francart, Tom; Lenssen, Anneke; Wouters, Jan

    2011-01-01

    In a previous study, it was shown that users of a cochlear implant and a contralateral hearing aid are sensitive to interaural time differences (ITDs). In the current study, we investigated (1) the influence on ITD sensitivity of bilaterally varying the place of excitation in the cochlea and of modulation frequency, and (2) the sensitivity to ITD with a 3-channel stimulus generated using continuous-interleaved-sampling (CIS)-like processing. The stimuli were (1) a high-frequency carrier (acoustic sinusoid and single-electrode electric pulse train), modulated with a half-wave-rectified low-frequency sinusoid (a so-called transposed stimulus), and (2) a 3-channel stimulus, generated by sending an acoustic click train through processing similar to the CIS strategy. Four bimodal listeners were sensitive to ITD for both stimulus types. For the first stimulus type, there was no significant influence on ITD sensitivity of the acoustic carrier frequency. Performance decreased with increasing modulation frequency with a limit of sensitivity at around 150-200 Hz. Sensitivity was similar for the single- and 3-channel stimulus. The results indicate the possibility of ITD perception with adapted clinical processors, which can lead to improved sound source localization and binaural unmasking. Copyright © 2010 S. Karger AG, Basel.

  14. Thermal stability of bimodal microstructure in magnesium alloy AZ91 processed by ECAP

    Energy Technology Data Exchange (ETDEWEB)

    Pantělejev, Libor, E-mail: pantelejev@fme.vutbr.cz [Institute of Materials Science and Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2896/2, 616 69 Brno (Czech Republic); NETME Centre, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2896/2, 616 69 Brno (Czech Republic); Štěpánek, Roman [Institute of Materials Science and Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2896/2, 616 69 Brno (Czech Republic); NETME Centre, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2896/2, 616 69 Brno (Czech Republic); Man, Ondřej [Institute of Materials Science and Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technická 2896/2, 616 69 Brno (Czech Republic)

    2015-09-15

    The changes in microstructure of equal channel angular pressing (ECAP) processed magnesium alloy AZ91 during thermal exposure were studied in this paper. The microstructure stability was investigated by means of electron backscatter diffraction (EBSD), which allowed to measure the changes in grain size, mutual ratio of low-angle boundaries (LABs) to high-angle ones (HABs) and local lattice distortion evaluated by the kernel average misorientation (KAM) parameter. It was found experimentally that the threshold temperature at which significant grain coarsening takes place is 350 °C. No modification to mean grain diameter occurs below this temperature, nonetheless, some changes in LAB and HAB fraction, as well as in local lattice distortion, can be observed. - Highlights: • Thermal stability of bimodal UFG AZ91 alloy was assessed by means of EBSD. • Threshold temperature for pronounced grain coarsening was found at 350 °C. • Below 350 °C increase in LAB fraction and local lattice distortion takes place. • Local lattice distortion (LLD) can be well described using KAM approach. • LLD is influenced by coarsening and precipitation of Mg{sub 17}Al{sub 12} particles.

  15. Influence of reproductive mode on metabolic costs of reproduction: insight from the bimodal lizard Zootoca vivipara.

    Science.gov (United States)

    Foucart, Thomas; Lourdais, Olivier; DeNardo, Dale F; Heulin, Benoit

    2014-11-15

    Examination of the selective forces behind the transition from oviparity to viviparity in vertebrates must include an understanding of the relative energy costs of the two reproductive modes. However, interspecific comparisons of reproductive mode are confounded by numerous other inherent differences among the species. Therefore, we compared oxygen consumption, as a reflection of energy costs, during reproduction in oviparous and viviparous females of the reproductively bimodal lizard Zootoca vivipara (Jaquin 1787). Female oxygen consumption progressively increased over the course of reproduction, peaking just prior to parition when it was 46% (oviparous form) and 82% (viviparous form) higher than it was at the pre-reproductive stage. Total increase in oxygen consumption (TIOC) during the pre-ovulation period was not different between the reproductive modes. Conversely, post-ovulation TIOC was more than three times higher in viviparous females, reflecting a dramatic increase in embryonic metabolism as well as maternal metabolic costs of pregnancy (MCP). MCP accounted for 22% of total metabolism in viviparous females, whereas it was negligible in oviparous females. Our results demonstrate that egg retention through the first third of development, as is typical of most oviparous squamates, entails minimal maternal energy demand, while extending retention imposes much greater metabolic constraints. Selection for transition from oviparity to viviparity must therefore provide benefits that outweigh not only the added burden associated with prolonged embryonic retention, but also the substantial additional energy costs that are incurred. © 2014. Published by The Company of Biologists Ltd.

  16. THE BIMODALITY OF ACCRETION IN T TAURI STARS AND BROWN DWARFS

    International Nuclear Information System (INIS)

    Vorobyov, E. I.; Basu, Shantanu

    2009-01-01

    We present numerical solutions of the collapse of prestellar cores that lead to the formation and evolution of circumstellar disks. The disk evolution is then followed for up to three million years. A variety of models of different initial masses and rotation rates allow us to study disk accretion around brown dwarfs and low-mass T Tauri stars (TTSs), with central object mass M * sun , as well as intermediate- and upper-mass TTSs (0.2 M sun * sun ). Our models include self-gravity and allow for nonaxisymmetric motions. In addition to the self-consistently generated gravitational torques, we introduce an effective turbulent α-viscosity with α = 0.01, which allows us particularly to model accretion in the low-mass regime where disk self-gravity is diminishing. A range of models with observationally motivated values of the initial ratio of rotational-to-gravitational energy yield a correlation between mass accretion rate M-dot and M * that is relatively steep, as observed. Additionally, our modeling reveals evidence for a bimodality in the M-dot - M * correlation, with a steeper slope at lower masses and a shallower slope at intermediate and upper masses, as also implied by observations. Furthermore, we show that the neglect of disk self-gravity leads to a much steeper M-dot - M * relation for intermediate- and upper-mass TTSs. This demonstrates that an accurate treatment of global self-gravity is essential to understanding observations of circumstellar disks.

  17. [An analysis of code-switching phenomenon in bimodal bilinguals (Libras and Portuguese).

    Science.gov (United States)

    de Sousa, Aline Nunes; de Quadros, Ronice Müller

    2012-01-01

    An interesting linguistic phenomenon that happens in the interaction among bilingual people is code-switching. In this paper, we are investigating code-switching among oral Brazilian Portuguese and Brazilian Sign Language - Libras, in a same enunciative chain, with the goal of identifying and analyzing the use of code-switching in the speech of a child and an adult (both hearing from deaf parents), interacting in an intermodal bilingual context, with deaf and hearing interlocutors. Code-switching in languages, in this case, occurs when a person stops to speak in Portuguese and he/she alternates to sign. This present research is a starting study, with qualitative analysis of data. Our corpus is composed of nine sections of interactions in Libras and oral Portuguese, recorded in video, part of the Bimodal Bilingual Development Project from UFSC. The data shows that adult and child's characteristics of code-switching seem to have similarities and differences. The adult seems to switch more worried about the course of the interaction. On the other hand, the child did not seem to use code-switching for specific pragmatic reasons. In regard to the switching extension, it is noted that both the child and the adult used more than one word sentences. The role of the interlocutors seems to be decisive in the interactions investigated here - especially for the adult, since the child is still acquiring awareness about the role of the interlocutor in an interaction.

  18. Bimodal cell death induced by high radiation doses in the radioresistant sf9 insect cell line

    International Nuclear Information System (INIS)

    Chandna, S.

    2003-01-01

    Full text: This study was conducted to investigate the mode(s) of cell death induced by high radiation doses in the highly radioresistant Sf9 insect ovarian cell line. Methods: Cells were exposed to γ-radiation doses 200Gy and 500Gy, harvested at various time intervals (6h-72h) following irradiation, and subjected to cell morphology assay, DNA agarose gel electrophoresis, single cell gel electrophoresis (SCGE; comet assay) and Annexin-V labeling for the detection of membrane phosphatidylserine externalization. Cell morphology was assessed in cells entrapped and fixed in agarose gel directly from the cell suspension, thus preventing the possible loss of fragments/ apoptotic bodies. Surviving fraction of Sf9 cells was 0.01 at 200Gy and 98%) undergoing extensive DNA fragmentation at 500Gy, whereas the frequency of cells with DNA fragmentation was considerably less (∼12%) at 200Gy. Conclusions: While the mode of cell death at 200Gy seems to be different from typical apoptosis, a dose of 500Gy induced bimodal cell death, with typical apoptotic as well as the atypical cell death observed at 200Gy

  19. Calcium provision to oviparous and viviparous embryos of the reproductively bimodal lizard Lacerta (Zootoca) vivipara.

    Science.gov (United States)

    Stewart, James R; Ecay, Tom W; Heulin, Benoit

    2009-08-01

    Embryos of oviparous squamate reptiles typically obtain calcium from both yolk and eggshell but differ from other oviparous amniotes (turtles, birds and crocodilians) because they are heavily dependent on calcium-rich yolk. Eggs of viviparous squamates lack calcareous eggshells, and embryos receive calcium solely from yolk or from both yolk and placenta. The pattern of calcium mobilization by amniote embryos has been predicted to influence the evolution of viviparity if embryos are dependent on calcium from the eggshell and calcium placentotrophy evolves subsequent to viviparity. We studied the pattern of maternal provision and embryonic utilization of calcium of an oviparous and a viviparous population of the reproductively bimodal lizard Lacerta vivipara to test the hypotheses: (1) oviparous embryos are not dependent on eggshell calcium and (2) calcium content of viviparous hatchlings does not differ from oviparous hatchlings. Our findings do not support either of these hypotheses because oviparous females oviposited eggs with heavily calcified shells and calcium-poor yolk, and embryonic mobilization of shell calcium was greater than for other oviparous squamates. The calcium content of yolk from viviparous females did not differ from oviparous yolk, but viviparous eggs lacked calcareous eggshells. Uterine secretion by viviparous females compensated for the low calcium content of yolk, and placental calcium transfer was among the highest recorded for squamates. The pattern of calcium provision in these two populations suggests that dependence on uterine calcium, either stored temporarily in an eggshell or transferred directly across a placenta, did not constrain the evolution of reproductive mode in this lineage.

  20. The morphology of human hyoid bone in relation to sex, age and body proportions.

    Science.gov (United States)

    Urbanová, P; Hejna, P; Zátopková, L; Šafr, M

    2013-06-01

    Morphological aspects of the human hyoid bone are, like many other skeletal elements in human body, greatly affected by individual's sex, age and body proportions. Still, the known sex-dependent bimodality of a number of body size characteristics overshadows the true within-group patterns. Given the ambiguity of the causal effects of age, sex and body size upon hyoid morphology the present study puts the relationship between shape of human hyoid bone and body proportions (height and weight) under scrutiny of a morphological study. Using 211 hyoid bones and landmark-based methods of geometric morphometrics, it was shown that the size of hyoid bones correlated positively with measured body dimensions but showed no correlation if the individual's sex was controlled for. For shape variables, our results revealed that hyoid morphology is clearly related to body size as expressed in terms of the height and weight. Yet, the hyoid shape was shown to result primarily from the sex-related bimodal distribution of studied body size descriptors which, in the case of the height-dependent model, exhibited opposite trends for males and females. Apart from the global hyoid shape given by spatial arrangements of the greater horns, body size dependency was translated into size and position of the hyoid body. None of the body size characters had any impact on hyoid asymmetry. Ultimately, sexually dimorphic variation was revealed for age-dependent changes in both size and shape of hyoid bones as male hyoids tend to be more susceptible to modifications with age than female bones. Copyright © 2013 Elsevier GmbH. All rights reserved.

  1. Job Strain and Casual Blood Pressure Distribution: Looking beyond the Adjusted Mean and Taking Gender, Age, and Use of Antihypertensives into Account. Results from ELSA-Brasil.

    Science.gov (United States)

    Juvanhol, Leidjaira Lopes; Melo, Enirtes Caetano Prates; Carvalho, Marilia Sá; Chor, Dóra; Mill, José Geraldo; Griep, Rosane Härter

    2017-04-22

    Methodological issues are pointed to as the main sources of inconsistencies in studies about the association between job strain and blood pressure (BP)/hypertension. Our aim was to analyze the relationship between job strain and the whole BP distribution, as well as potential differences by gender, age, and use of antihypertensives. Additionally, we addressed issues relating to the operationalization of the exposure and outcome variables that influence the study of their inter-relations. We evaluated the baseline date of 12,038 participants enrolled in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) (2008-2010), a multicenter cohort study of 35-74-year-old civil servants. Job strain was assessed by the Demand-Control-Support Questionnaire. The distribution of casual BP by categories of job strain was compared by a combination of exploratory techniques. Participants were classified into three subgroups (normotensives, medicated hypertensives, and unmedicated hypertensives), and analyses were stratified by gender and age. The relationship between job strain and casual BP varied along the whole outcome distribution. Hypertensive participants had greater differences in casual BP by job strain category, especially medicated hypertensives. Differences in casual BP were also greater for systolic than for diastolic BP and for older participants. No differences were encountered by gender. The exclusion of participants susceptible to misclassification for the exposure and outcome variables increased the differences observed between the categories of low and high job strain. In conclusion, the relationship between job strain and casual BP varied along the whole outcome distribution and by use of antihypertensive drugs, age, and BP parameter evaluated. Misclassification for exposure and outcome variables should be considered in analyses of this topic.

  2. Improvement of and Parameter Identification for the Bimodal Time-Varying Modified Kanai-Tajimi Power Spectral Model

    Directory of Open Access Journals (Sweden)

    Huiguo Chen

    2017-01-01

    Full Text Available Based on the Kanai-Tajimi power spectrum filtering method proposed by Du Xiuli et al., a genetic algorithm and a quadratic optimization identification technique are employed to improve the bimodal time-varying modified Kanai-Tajimi power spectral model and the parameter identification method proposed by Vlachos et al. Additionally, a method for modeling time-varying power spectrum parameters for ground motion is proposed. The 8244 Orion and Chi-Chi earthquake accelerograms are selected as examples for time-varying power spectral model parameter identification and ground motion simulations to verify the feasibility and effectiveness of the improved bimodal time-varying modified Kanai-Tajimi power spectral model. The results of this study provide important references for designing ground motion inputs for seismic analyses of major engineering structures.

  3. Using isotopes to constrain water flux and age estimates in snow-influenced catchments using the STARR (Spatially distributed Tracer-Aided Rainfall-Runoff) model

    Science.gov (United States)

    Ala-aho, Pertti; Tetzlaff, Doerthe; McNamara, James P.; Laudon, Hjalmar; Soulsby, Chris

    2017-10-01

    Tracer-aided hydrological models are increasingly used to reveal fundamentals of runoff generation processes and water travel times in catchments. Modelling studies integrating stable water isotopes as tracers are mostly based in temperate and warm climates, leaving catchments with strong snow influences underrepresented in the literature. Such catchments are challenging, as the isotopic tracer signals in water entering the catchments as snowmelt are typically distorted from incoming precipitation due to fractionation processes in seasonal snowpack. We used the Spatially distributed Tracer-Aided Rainfall-Runoff (STARR) model to simulate fluxes, storage, and mixing of water and tracers, as well as estimating water ages in three long-term experimental catchments with varying degrees of snow influence and contrasting landscape characteristics. In the context of northern catchments the sites have exceptionally long and rich data sets of hydrometric data and - most importantly - stable water isotopes for both rain and snow conditions. To adapt the STARR model for sites with strong snow influence, we used a novel parsimonious calculation scheme that takes into account the isotopic fractionation through snow sublimation and snowmelt. The modified STARR setup simulated the streamflows, isotope ratios, and snow pack dynamics quite well in all three catchments. From this, our simulations indicated contrasting median water ages and water age distributions between catchments brought about mainly by differences in topography and soil characteristics. However, the variable degree of snow influence in catchments also had a major influence on the stream hydrograph, storage dynamics, and water age distributions, which was captured by the model. Our study suggested that snow sublimation fractionation processes can be important to include in tracer-aided modelling for catchments with seasonal snowpack, while the influence of fractionation during snowmelt could not be unequivocally

  4. Changes in sex and non-sex hormones and distribution of erythrocyte antigens in reproductive age women with tumors of body of uterus in Adjara.

    Science.gov (United States)

    Nakashidze, I; Kotrikadze, N; Diasamidze, A; Nagervadze, M; Ramishvili, L

    2013-04-01

    The aim the research was to study the hormonal state of reproductive age women with tumors of body of uterus. The quantitative changes of sex steroid hormones: progesterone (P), estradiol (E), testosterone (T), gonadotropine -Luteinizing hormone (LH) and Follicle-stimulating hormone (FSH) were investigated. Distribution of ABO blood group antigens and Rh-Hr systems genetic variants in the blood of women living in Adjara Region was also studied. For study was used reproductive age women's blood with benign (fibromioma) and malignant (endometrial cancer) tumors of body of uterus (the middle age was 20-45 years). The determination of hormones was made by the enzymatic analysis method (ELAIZA). For the research of blood groups, were used the immunoserologic methods. The study have revealed that in blood of reproductive age women with benign and malignant tumors of body of uterus, level of estradiol was increased while levels of progesterone and testosterone were sharply reduced. Amount of Follicle-stimulating hormone and Luteinizing hormone were also increased. It's significant that, both hormones were sharply increased in case of cancer of body of uterus, in comparison with control group and benign tumor. According to distribution of ABO blood group phenotypes - O (I) phenotypic group of ABO system has its highest frequency in blood of women with cancer of body of uterus. Cancer of body of uterus is associated with O (I) phenotypic groups; benign tumor of body of uterus - with A(II) and AB(IV) phenotypic groups. Women with cc and EE genetic variants of Rh-Hr system have sensitivity to the development of benign and malignant tumors of body of uterus; women with ee genetic variant have lower sensitivity towards body of uterus cancer and sharply expressed sensitivity to uterus benign tumors. In women with malignant tumors of body of uterus the frequency of distribution of Rh-Hr system CC genetic variant was sharply reduced.

  5. Android fat distribution affects some hemostatic parameters in women with polycystic ovary syndrome compared with healthy control subjects matched for age and body mass index.

    Science.gov (United States)

    de Mendonça-Louzeiro, Maria Raquel Marques Furtado; Annichino-Bizzacchi, Joyce Maria; Benetti-Pinto, Cristina Laguna

    2015-08-01

    To correlate hemostatic parameters with clinical markers of fat distribution and laboratory variables in women with polycystic ovary syndrome (PCOS) compared with healthy control subjects. Cross-sectional study. Tertiary teaching hospital. Forty-five women with PCOS and 45 control women matched for age and body mass index (BMI). Clinical evaluation and venipuncture. Age, BMI, waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR), Ferriman-Gallwey index, fasting glucose, fasting insulin, total testosterone, free testosterone (FT), thrombin-activatable fibrinolysis inhibitor (TAFI), D-dimer, plasminogen activator inhibitor (PAI) 1, and the parameters of thrombin generation test (TGT), including the lag time (Tlag), time to peak thrombin generation (Tmax), peak concentration (Cmax), and the area under the thrombin generation curve (TAUC). In the PCOS group, BMI and WC correlated positively with TAFI, D-dimer, PAI-1, Cmax, and TAUC; HC with D-dimer and PAI-1; WHR with TAFI, D-dimer, and PAI-1; glucose with TAFI; insulin and homeostasis-model assessment of insulin resistance with PAI-1; and FT with Cmax and TAUC. Age correlated positively with D-dimer and PAI-1, and negatively with Tlag and Tmax. In the control group, there were no correlations between clinical markers of fat distribution and hemostatic parameters, but age and fasting glucose correlated positively with PAI-1, and FT with Tmax and TAUC. In PCOS, android body fat distribution may directly affect hemostatic parameters, particularly in young and overweight women. Further studies are needed to establish a correlation between these results and an increase in thromboembolic risk. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  6. Habitat association and seasonality in a mosaic and bimodal hybrid zone between Chorthippus brunneus and C. jacobsi (Orthoptera: Acrididae.

    Directory of Open Access Journals (Sweden)

    Richard I Bailey

    Full Text Available Understanding why some hybrid zones are bimodal and others unimodal can aid in identifying barriers to gene exchange following secondary contact. The hybrid zone between the grasshoppers Chorthippus brunneus and C. jacobsi contains a mix of allopatric parental populations and inter-mingled bimodal and unimodal sympatric populations, and provides an ideal system to examine the roles of local selection and gene flow between populations in maintaining bimodality. However, it is first necessary to confirm, over a larger spatial scale, previously identified associations between population composition and season and habitat. Here we use cline-fitting of one morphological and one song trait along two valley transects, and intervening mountains, to confirm previously identified habitat associations (mountain versus valley and seasonal changes in population composition. As expected from previous findings of studies on a smaller spatial scale, C. jacobsi dominated mountain habitats and mixed populations dominated valleys, and C. brunneus became more prevalent in August. Controlling for habitat and incorporating into the analysis seasonal changes in cline parameters and the standard errors of parental trait values revealed wider clines than previous studies (best estimates of 6.4 to 24.5 km in our study versus 2.8 to 4.7 km in previous studies and increased percentage of trait variance explained (52.7% and 61.5% for transects 1 and 2 respectively, versus 17.6%. Revealing such strong and consistent patterns within a complex hybrid zone will allow more focused examination of the causes of variation in bimodality in mixed populations, in particular the roles of local selection versus habitat heterogeneity and gene flow between differentiated populations.

  7. Monte Carlo analysis of field water flow comparing uni- and bimodal effective hydraulic parameters for structured soil.

    Science.gov (United States)

    Coppola, A; Basile, A; Comegna, A; Lamaddalena, N

    2009-02-16

    Soil structure critically affects the hydrological behaviour of soils. In this paper, we examined the impact of areal heterogeneity of hydraulic properties of a structured soil on soil ensemble behaviour for various soil water flow processes with different top boundary conditions (redistribution and drainage plus evaporation and infiltration). Using a numerical solution of the Richards' equation in a stochastic framework, the ensemble characteristics and flow dynamics were studied for drying and wetting processes observed during a time interval of ten days when a series of relatively intense rainfall events occurred. The effects of using unimodal and bimodal interpretative models of hydraulic properties on the ensemble hydrological behaviour of the soil were illustrated by comparing predictions to mean water contents measured over time in several sites at field scale. Although the differences between unimodal and bimodal fitting are not significant in terms of goodness of fit, the differences in process predictions are considerable with the bimodal soil simulating water content measurements much better than unimodal soil. We also investigated the relative contribution of the soil variability of each parameter on the variance of the water contents obtained as the main output of the stochastic simulations. The variability of the structural parameter, weighting the two pore space fractions in the bimodal interpretative model, has the largest contribution to water content variance. The contribution of each parameter depends only partly on the coefficient of variation, much more on the sensitivity of the model to the parameters and on the flow process being observed. We observed that the contribution of the retention parameters to uncertainty increases during drainage processes; the opposite occurs with the hydraulic conductivity parameters.

  8. Habitat association and seasonality in a mosaic and bimodal hybrid zone between Chorthippus brunneus and C. jacobsi (Orthoptera: Acrididae).

    Science.gov (United States)

    Bailey, Richard I; Saldamando-Benjumea, Clara I; Tatsuta, Haruki; Butlin, Roger K

    2012-01-01

    Understanding why some hybrid zones are bimodal and others unimodal can aid in identifying barriers to gene exchange following secondary contact. The hybrid zone between the grasshoppers Chorthippus brunneus and C. jacobsi contains a mix of allopatric parental populations and inter-mingled bimodal and unimodal sympatric populations, and provides an ideal system to examine the roles of local selection and gene flow between populations in maintaining bimodality. However, it is first necessary to confirm, over a larger spatial scale, previously identified associations between population composition and season and habitat. Here we use cline-fitting of one morphological and one song trait along two valley transects, and intervening mountains, to confirm previously identified habitat associations (mountain versus valley) and seasonal changes in population composition. As expected from previous findings of studies on a smaller spatial scale, C. jacobsi dominated mountain habitats and mixed populations dominated valleys, and C. brunneus became more prevalent in August. Controlling for habitat and incorporating into the analysis seasonal changes in cline parameters and the standard errors of parental trait values revealed wider clines than previous studies (best estimates of 6.4 to 24.5 km in our study versus 2.8 to 4.7 km in previous studies) and increased percentage of trait variance explained (52.7% and 61.5% for transects 1 and 2 respectively, versus 17.6%). Revealing such strong and consistent patterns within a complex hybrid zone will allow more focused examination of the causes of variation in bimodality in mixed populations, in particular the roles of local selection versus habitat heterogeneity and gene flow between differentiated populations.

  9. Identification of defect distribution at ferroelectric domain walls from evolution of nonlinear dielectric response during the aging process

    Czech Academy of Sciences Publication Activity Database

    Mokrý, Pavel; Sluka, T.

    2016-01-01

    Roč. 93, č. 6 (2016), č. článku 064114. ISSN 2469-9950 R&D Projects: GA ČR(CZ) GA14-32228S Institutional support: RVO:61389021 Keywords : Nonlinear dielectric response * ferroelectric domain walls * aging process * phase field simulations Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.836, year: 2016 http://journals.aps.org/prb/abstract/10.1103/PhysRevB.93.064114

  10. Characterization of carbofuran bound residues and the effect of ageing on their distribution and bioavailability in the soil of a sugar beet field in north-western Morocco

    Directory of Open Access Journals (Sweden)

    Mohamed Benicha

    2016-06-01

    Full Text Available This study was undertaken to investigate distribution, fractionation, bioavailability and remobilization characteristics of bound soil-aged carbofuran and the effect of ageing in clay soil in a typical field of sugar beet at Loukkos in northwest Morocco. Results indicate that initially there were high levels of bound residues (BR in the humin fraction, which decreased with incubation time and ageing of the BR. While in the fulvic and humic acid fractions, the amount of BR increased with the ageing of the BR and occurred predominantly (60% in the fulvic acid fraction. The possibility of the mineralization and release of BR with ageing was studied using fresh soil and an incubation period of 90 days. The results indicate that the ageing of the residues have a great influence on the remobilization and mineralization rates of carbofuran BR; 9.45 to 14.90% of the total BR was released as extractable residues, and 1.95 to 4.15% was mineralized depending on the age of the residues in soil and the soil-aged carbofuran BR. The incorporation of the residues in the humin fraction is considered to be a threat to the environment. On the other hand, the clear prevalence of residues in the fulvic and humic acid fractions, may have an important effect on their bioavailability and movement in soil. Moreover, the re-extractability of BR could pose a potential environmental risk. Consequently, the BR remobilized must be taken into account when assessing for registration processes the environmental risk of pesticides persisting in soils.

  11. Age-related changes in pre- and post-conization HPV genotype distribution among women with high-grade cervical intraepithelial neoplasia.

    Science.gov (United States)

    Giannella, Luca; Fodero, Cristina; Boselli, Fausto; Rubino, Teresa; Mfuta, Kabala; Prandi, Sonia

    2017-04-01

    To assess the effect of age on pre- and post-conization HPV genotype distribution. The present retrospective observational study included consecutive women with high-grade cervical intraepithelial neoplasia who underwent conization at the Cervical Cancer Screening Centre of Reggio Emilia, Italy, and University Hospital of Modena, Italy, between February 1, 2012, and October 31, 2014. Pre-conization and 6-month post-conization HPV genotyping results were compared between four age groups (<30, 30-39, 40-49, and ≥50 years) and age-related changes in the HPV genotypes present were evaluated. There were 162 patients included. The lowest occurrence of pre-conization high-risk and probable high-risk HPV genotypes was observed among patients aged at least 50 years when compared with younger patients (P=0.017). Conversely, women aged at least 50 years exhibited the highest level of post-conization high-risk and probable high-risk HPV genotypes (P=0.043). Additionally, an increasing incidence of recording identical pre- and post-conization HPV genotypes was associated with increasing age (P=0.024), as was increasing post-treatment recurrence of cervical intraepithelial neoplasia grade 2+ (P=0.030). The presence of high-risk and probable high-risk HPV genotypes was lowest among older patients before conization and was highest among these patients post-conization; post-treatment HPV clearance decreased with age and increasing age could be a risk factor for post-conization recurrence. © 2017 International Federation of Gynecology and Obstetrics.

  12. Transmission electron microscopy of aged Ti-10Mo-20Nb alloy after hot swaging; Microscopia eletronica de transmissao da liga Ti-10Mo-20Nb envelhecida apos forjamento a quente

    Energy Technology Data Exchange (ETDEWEB)

    Gabriel, Sinara Borborema, E-mail: sinarab@msn.com [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Baldan, Renato, E-mail: renatobaldan@gmail.com [Universidade de Sao Paulo (EEL/USP), Lorena, SP (Brazil). Escola de Engenharia; Torres, Juliana; Oliveira, Nathalia Rodrigues, E-mail: juliana_torres_5@hotmail.com, E-mail: nathalia_roliveira@yahoo.com.br [Centro Universitario de Volta Redonda (UNIFOA), Volta Redonda, RJ (Brazil); Nunes, Carlos Angelo; Mei, Paulo Roberto, E-mail: cnunes@demar.eel.usp.br, E-mail: pmei@fem.unicamp.br [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil)

    2014-08-15

    Ti alloys are widely used in biomedical applications. Within this class, metastable β -Ti alloys stand, because through thermomechanical processing it is possible to obtain mechanical properties and in particular one suitable Young's modulus for biomedical applications. These alloys require high mechanical strength and a low Young's modulus to avoid stress shielding. Preliminary studies showed that the microstructure of the Ti-10Mo- 20Nb alloy after cold forging and aging 500 °C/24 h consisted in bimodal distribution of α phase in the β matrix. The aim of this study was to characterize the microstructure of Ti-10Mo-20Nb alloy after hot forging and aging at 500 °C for 24 hours. Microstructural characterization consisted of analyzes by X-ray diffraction and transmission electron microscopy. According to the results, while the cold forging resulted in a bimodal α distribution in the β matrix, hot forging resulted in a thin and homogeneous α precipitation in the β matrix. (author)

  13. Age- and Sex-Dependent Values of the Distribution of Body Composition Parameters Among Chinese Children Using the Hattori Chart.

    Science.gov (United States)

    Guo, Bin; Hu, Li; Wu, Qiulian; Gong, Jian; Xu, Hao

    This study aimed to examine the relationship between the fat-free mass (FFM) and fat mass (FM) and between the fat-free mass index (FFMI) and fat mass index (FMI) in Chinese children using the Hattori chart and to compare the changing pattern with Korean counterparts. In this study, 1541 (764 girls) children and adolescents aged 5-19 yr were recruited from southern China. The subjects' body composition was measured using dual-energy X-ray absorptiometry. The relationship between FFM and FM and between FFMI and FMI were delineated using the Hattori chart. Between 5 and 12 yr, a concurrent increase in FFM and FM and in FFMI and FMI was found in both sexes. After 12 yr, the age-related changing patterns are generally characterized by a sharp increase in FM, with a relatively small increase in FFM for girls, and a sharp increase in FFM, with a relatively little fluctuation in FM for boys. The increase in weight and BMI with age for this stage is largely due to the increase in FFM and FFMI in boys and in both the FFM and FM and FFMI and FMI components in girls. Sex differences in the patterns of body composition were found in Chinese children and adolescents. Copyright © 2016 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

  14. Distribution of axial length, anterior chamber depth, and corneal curvature in an aged population in South China.

    Science.gov (United States)

    Chen, Hui; Lin, Haotian; Lin, Zhuoling; Chen, Jingjing; Chen, Weirong

    2016-05-01

    Ocular biometry is important for preoperative assessment in cataract and anterior segment surgery. The purpose of this study was to investigate normative ocular biometric parameters and their associations in an older Chinese population. This was a cross-sectional observational study. From 2013 to 2014, we recruited inhabitants aged 50 years or older in Guangzhou, China. Among 1,117 participants in the study, data from 1,015 phakic right eyes were used for analyses. Ocular parameters including axial length (AL), anterior chamber depth (ACD), and corneal curvature (K) were measured using an IOL Master. The mean AL, ACD, and K were 23.48 mm [95 % confidence interval (CI), 23.40-23.55], 3.03 mm (CI, 3.01-3.05), and 44.20 mm (CI, 44.11-44.29), respectively. A mean reduction in ACD with age was observed (P = 0.002) in male subjects but not in female subjects (P = 0.558). Male subjects had significantly longer ALs (23.68 mm versus 23.23 mm, P population in South China. The AL in this Chinese cohort was greater than that observed in the Singaporean Chinese but smaller than that observed in Malaysia and for Caucasians. The Chinese have a shallower ACD than some other racial groups. Age and sex were the most consistent predictors of ocular biometry in the older population from South China.

  15. Population age structure and reproductive behavior of the monocarpic perennial Heracleum mantegazzianum (Apiaceae) in its native and invaded distribution ranges.

    Science.gov (United States)

    Pergl, Jan; Perglová, Irena; Pysek, Petr; Dietz, Hansjörg

    2006-07-01

    Many invasive species are benign in their native region-are there interactions between their key traits and the new habitats that explain invasion success? The giant perennial herb Heracleum mantegazzianum is a problematic invader in Europe and is also naturalized in North America. We compared its population structure and reproductive behavior in the native (W. Caucasus) and invaded (Czech Republic) areas in managed (pastures) and unmanaged sites. The age structure of the populations and age at flowering were analyzed using herb-chronology, a method based on counting annual rings in the secondary xylem of roots. The species was strictly monocarpic; most plants in unmanaged sites in the invaded range flowered in the third and fourth yr (maximum 12 yr). In unmanaged habitats, plants from the native range flowered later than those from the invaded range. In both ranges, flowering was delayed in managed sites where the population density was higher and most plants flowered around the fifth year. Reproductive output of individual plants was neither related to population density nor to age at flowering. More favorable climatic conditions in the invaded region, together with increased chances for dispersal in a densely colonized central Europe, seemed to allow the massive invasion.

  16. Producing laminated NiAl with bimodal distribution of grain size by solid–liquid reaction treatment

    DEFF Research Database (Denmark)

    Fan, G.H.; Wang, Q.W.; Du, Y.

    2014-01-01

    The prospect of combining laminated structure design and grain size tailoring to toughen brittle materials is examined. Laminated NiAl consisting of coarse-grained layers and fine-grained layers was fabricated by solid–liquid reaction treatment of stacking Ni and Al foils. The fracture toughness ...

  17. Power Management and Distribution System Developed for Thermionic Power Converters

    Science.gov (United States)

    Baez, Anastacio N.

    1998-01-01

    A spacecraft solar, bimodal system combines propulsion and power generation into a single integrated system. An Integrated Solar Upper Stage (ISUS) provides orbital transfer capabilities, power generation for payloads, and onboard propulsion to the spacecraft. A key benefit of a bimodal system is a greater payload-to-spacecraft mass ratio resulting in lower launch vehicle requirements. Scaling down to smaller launch vehicles increases space access by reducing overall mission cost. NASA has joined efforts with the Air Force Phillips Laboratory to develop enabling technologies for such a system. The NASA/Air Force bimodal concept uses solar concentrators to focus energy into an integrated power plant. This power plant consists of a graphite core that stores thermal energy within a cavity. An array of thermionic converters encircles the graphite cavity and provides electrical energy conversion functions. During the power generation phase of the bimodal system, the thermionic converters are exposed to the heated cavity and convert the thermal energy to electricity. Near-term efforts of the ISUS bimodal program are focused on a ground demonstration of key technologies in order to proceed to a full space flight test. Thermionic power generation is one key technology of the bimodal concept. Thermionic power converters impose unique operating requirements upon a power management and distribution (PMAD) system design. Single thermionic converters supply large currents at very low voltages. Operating voltages can vary over a range of up to 3 to 1 as a function of operating temperature. Most spacecraft loads require regulated 28-volts direct-current (Vdc) power. A combination of series-connected converters and powerprocessing boosters is required to deliver power to the spacecraft's payloads at this level.

  18. Age, composition, and areal distribution of the Pliocene Lawlor Tuff, and three younger Pliocene tuffs, California and Nevada

    Science.gov (United States)

    Sarna-Wojcicki, Andrei M.; Deino, Alan L.; Fleck, Robert J.; McLaughlin, Robert J.; Wagner, David; Wan, Elmira; Wahl, David B.; Hillhouse, John W.; Perkins, Michael

    2011-01-01

    The Lawlor Tuff is a widespread dacitic tephra layer produced by Plinian eruptions and ash flows derived from the Sonoma Volcanics, a volcanic area north of San Francisco Bay in the central Coast Ranges of California, USA. The younger, chemically similar Huichica tuff, the tuff of Napa, and the tuff of Monticello Road sequentially overlie the Lawlor Tuff, and were erupted from the same volcanic field. We obtain new laser-fusion and incremental-heating 40Ar/39Ar isochron and plateau ages of 4.834 ± 0.011, 4.76 ± 0.03, ≤4.70 ± 0.03, and 4.50 ± 0.02 Ma (1 sigma), respectively, for these layers. The ages are concordant with their stratigraphic positions and are significantly older than those determined previously by the K-Ar method on the same tuffs in previous studies.Based on offsets of the ash-flow phase of the Lawlor Tuff by strands of the eastern San Andreas fault system within the northeastern San Francisco Bay area, total offset east of the Rodgers Creek–Healdsburg fault is estimated to be in the range of 36 to 56 km, with corresponding displacement rates between 8.4 and 11.6 mm/yr over the past ∼4.83 Ma.We identify these tuffs by their chemical, petrographic, and magnetic characteristics over a large area in California and western Nevada, and at a number of new localities. They are thus unique chronostratigraphic markers that allow correlation of marine and terrestrial sedimentary and volcanic strata of early Pliocene age for their region of fallout. The tuff of Monticello Road is identified only near its eruptive source.

  19. [Adenoma of the colon or rectum: relationship between histological structure, polyp size and site and age distribution (author's transl)].

    Science.gov (United States)

    Frimberger, E; Kühner, W; Seib, H J; Ottenjann, R

    1978-04-14

    Among 1258 polyps from the lower gastro-intestinal tract removed by rectoscopy or coloscopy and examined histologically there were 744 adenomas, 72% tubular, 27% papillary and 1% villous. 96.5% of all adenomas were extracted from patients aged over 40 years. Four fifths of the tumours were found in the rectum and sigmoid colon. Only 6% of the tubular adenomas were more than 15 mm in diameter, compared with 32% of papillary and 57% of villous adenomas. The special significance of the adenomas lies in their potential malignancy (adenoma-to-cancer sequence).

  20. Distribution, facies, ages, and proposed tectonic associations of regionally metamorphosed rocks in Southwestern Alaska and the Alaska Peninsula

    Science.gov (United States)

    Dusel-Bacon, Cynthia; Doyle, Elizabeth O.; Box, Stephen E.

    1996-01-01

    The oldest dated metamorphic sequence in Alaska, the fault-bounded Kilbuck Terrane, consists of continental rocks that were metamorphosed under amphibolite-facies conditions during early Proterozoic (1.77 Ga) time. Proterozoic or early Paleozoic metamorphic ages are also possible for greenschist- and amphibolite-facies continental rocks in interior Alaska (Ruby and Nixon Fork terranes). Medium-grade metamorphism on the Alaska Peninsula accompanied intrusion of a Jurassic arc. North of Bristol Bay, low-grade, locally high-pressure Mesozoic metamorphism is attributed to the progressive underthrusting of a subduction complex beneath an oceanic arc followed by underthrusting of the Kilbuck Terrane beneath the subduction complex.

  1. Osteoprotegerin Levels Decrease During Testosterone Therapy in Aging Men and are Associated with Changed Distribution of Regional Fat

    DEFF Research Database (Denmark)

    Frederiksen, L; Glintborg, D; Højlund, K

    2013-01-01

    The cardiovascular effects of testosterone treatment are debated. Osteoprotegerin (OPG) is an independent marker of cardiovascular risk. We investigated the effect of testosterone therapy on OPG levels in aging men with low normal bioavailable testosterone levels. A randomized, double-blinded, pl...... LBM (Δ LBM positive), n=14. Data are presented as median (interquartile range). Testosterone therapy decreased total fat mass and SAT, whereas VAT was unchanged (n=38). OPG levels decreased during testosterone therapy (from 2.0 (1.9-2.5) to 1.9 (1.6-2.2) ng/ml, p...

  2. Penicillin resistance and serotype distribution of Streptococcus pneumoniae in Ghanaian children less than six years of age

    DEFF Research Database (Denmark)

    Dayie, Nicholas T. K. D.; Arhin, Reuben E.; Newman, Mercy J.

    2013-01-01

    resistance. Conclusions: These findings indicate that the 13-valent pneumococcal conjugate vaccine (PCV-13) recently introduced in Ghana will cover 48% and 51% of the serotypes identified in Accra and Tamale, respectively. The 23-valent pneumococcal polysaccharide vaccine (PPV-23) will cover 54% of all......Background: The objective of this study was to determine the prevalence of nasopharyngeal carriage, serotype distribution, and penicillin resistance of Streptococcus pneumoniae in children 2 mu g/ml and were classified as fully penicillin resistant with 45% of the isolates having intermediate...... serotypes detected. The two penicillin resistant isolates (MIC 32 mu g/ml) were serotypes included in both PCV-13 and PPV-23. A nationwide monitoring system of penicillin susceptibility patterns and pneumococcal serotypes is recommended....

  3. Age-related changes in phase-space distribution of ABPM data in normotensive and hypertensive patients.

    Science.gov (United States)

    Recordati, Giorgio

    2011-04-26

    The data collected by ambulatory blood pressure monitoring have been studied in the phase-space of R-R interval and blood pressure and their individual distribution quantified by the slope of the regression line through 24-h values. This slope has been termed "ambulatory autonomic reciprocity index" and abbreviated as AARIs and AARId, the "s" and "d" indicating the relation with systolic and diastolic blood pressure respectively. Ambulatory monitoring was performed in 200 normotensive (NT: 135 females) and 200 untreated hypertensive patients (HT: 59 females). The AARIs was: NT: -6.04±2.7 and HT: -4.69±2.4ms/mmHg, respectively (p<0.001); the AARId was: -7.04±2.9 for NT and -5.79±2.8 for HT subjects (p<0.001). When distributed by decades of life the steepest AARIs occurred at the 20-29 decade, while the flattest at the 60-69 decade. At the 60-69 decade and above, the AARIs was similar in both groups (ANOVA o.w. NT: p<0.001; HT: p<0.01). AARIs and AARId were strongly correlated with 24-h variability of R-R interval, either 24-h standard deviation or coefficient of variation (p<0.001), and poorly correlated with 24-h variability of blood pressure. These data suggest that the AARI, when seen in the context of the "Autonomic Space", may be viewed as a 24-h period index of centrally driven cardiovagal function. Being based on both blood pressure and heart rate measurements, the AARI may become clinically useful to address life style changes and pharmacological treatment of hypertensive patients towards optimal results. Copyright © 2010 Elsevier B.V. All rights reserved.

  4. Distribution of Third Molar Impactions Among Rural and Urban Dwellers in the Age Group of 22-30 years in South India: A Comparative Study.

    Science.gov (United States)

    Venu Gopal Reddy, K

    2012-09-01

    (1) To collect the data related to distribution of third molar impactions among rural population by clinical and radiological examinations. (2) To collect the information on distribution of third molar impactions among urban population by clinical and radiological examinations. (3) To compare the patterns of distribution of third molar impactions among rural and urban residents with respect to type of impaction, arch, gender and age. A cross-sectional study was conducted in Dharwad district of Karnataka state located in South India involving 630 rural and 270 urban subjects as per demographic profile of India. A two stage sampling procedure was adopted in the selection of the sample. Data was analyzed using STATISTICA-6.0. χ(2) test was used to explore the association between different variables and third molar impactions. A P ≤ 0.05 was considered statistically significant. 14.92% of rural subjects and 27.40% urban subjects were reported to be suffering from third molar impactions. The overall prevalence of third molar impactions among the study subjects was found to be 18.67%. A significant association was noticed between the 'different arches' and distribution of third molar impactions in both rural and urban population. Subjects with vertical impactions were found to be most common in both the groups.

  5. Compound-Specific Radiocarbon Dating Reveals the Age Distribution of Plant-Wax Biomarkers Exported to the Bengal Fan

    Science.gov (United States)

    Galy, V.; French, K. L.; Hein, C. J.; Haghipour, N.; Wacker, L.; Kudrass, H.; Eglinton, T. I.

    2017-12-01

    The stable isotope composition of leaf-wax compounds preserved in lacustrine and marine sediments has been widely used to reconstruct terrestrial paleo-environments. However, the timescales of plant-wax storage in continental reservoirs before riverine export are not well known, representing a key uncertainty in paleo-environment studies. We couple numerical models with bulk and leaf-wax fatty acid organic 13C and 14C signatures hosted in a high-deposition-rate sediment core from the Bengal shelf canyon in order to estimate storage timescales within the Ganges-Brahmaputra catchment area. The fatty acid 14C record reveals a muted nuclear weapons bomb spike, requiring that the Ganges-Brahmaputra river system exports a mixture of young and old (pre-aged) leaf-wax compounds. According to numerical simulations, 79-83% of the leaf-wax fatty acids in this core are sourced from continental reservoirs that store organic carbon on an average of 1000-1200 calendar years, while the remainder has an average age of 15 years. These results demonstrate that a majority of the leaf-wax compounds produced in the Ganges-Brahmaputra river basin was stored in soils, floodplains, and wetlands prior to its export to the Bengal Fan. We will discuss the implications of these findings for plant-wax based paleoenvironmental records.

  6. The Distribution and Ages of Star Clusters in the Small Magellanic Cloud: Constraints on the Interaction History of the Magellanic Clouds

    Science.gov (United States)

    Bitsakis, Theodoros; González-Lópezlira, R. A.; Bonfini, P.; Bruzual, G.; Maravelias, G.; Zaritsky, D.; Charlot, S.; Ramírez-Siordia, V. H.

    2018-02-01

    We present a new study of the spatial distribution and ages of the star clusters in the Small Magellanic Cloud (SMC). To detect and estimate the ages of the star clusters we rely on the new fully automated method developed by Bitsakis et al. Our code detects 1319 star clusters in the central 18 deg2 of the SMC we surveyed (1108 of which have never been reported before). The age distribution of those clusters suggests enhanced cluster formation around 240 Myr ago. It also implies significant differences in the cluster distribution of the bar with respect to the rest of the galaxy, with the younger clusters being predominantly located in the bar. Having used the same setup, and data from the same surveys as for our previous study of the LMC, we are able to robustly compare the cluster properties between the two galaxies. Our results suggest that the bulk of the clusters in both galaxies were formed approximately 300 Myr ago, probably during a direct collision between the two galaxies. On the other hand, the locations of the young (≤50 Myr) clusters in both Magellanic Clouds, found where their bars join the H I arms, suggest that cluster formation in those regions is a result of internal dynamical processes. Finally, we discuss the potential causes of the apparent outside-in quenching of cluster formation that we observe in the SMC. Our findings are consistent with an evolutionary scheme where the interactions between the Magellanic Clouds constitute the major mechanism driving their overall evolution.

  7. Thyroid volume in hypothyroidism due to autoimmune disease follows a unimodal distribution: evidence against primary thyroid atrophy and autoimmune thyroiditis being distinct diseases

    DEFF Research Database (Denmark)

    Carlé, Allan; Pedersen, Inge Bülow; Knudsen, Nils

    2009-01-01

    CONTEXT: Primary overt autoimmune hypothyroidism is often divided into primary idiopathic hypothyroidism with thyroid atrophy (Ord's disease) and hypothyroidism with goitre (Hashimoto's disease). OBJECTIVE: The aim of the present study was to characterize the two subtypes of disease. DESIGN...... program including thyroid ultrasonography and measurements of thyroid autoantibodies. Of the 144 patients investigated (58% of all invited), 139 were compared with 556 sex-, age-, and region-matched controls from the cohort. RESULTS: Patients had lower median (11.6 ml vs. 13.5 ml, P = 0.001) and a more...... dispersed distribution of thyroid volumes compared with controls (P thyroid volume showed a Gaussian distribution in both males and females with no bimodal pattern. Nearly all patients had measurable thyroid autoantibodies, but with increasing thyroid volume (quartile I, II, III, and IV...

  8. Conventional and Bimodal Nuclear Thermal Rocket (NTR) Artificial Gravity Mars Transfer Vehicle Concepts

    Science.gov (United States)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2016-01-01

    A variety of countermeasures have been developed to address the debilitating physiological effects of zero-gravity (0-g) experienced by cosmonauts and astronauts during their approximately 0.5 to 1.2 year long stays in low Earth orbit (LEO). Longer interplanetary flights, combined with possible prolonged stays in Mars orbit, could subject crewmembers to up to approximately 2.5 years of weightlessness. In view of known and recently diagnosed problems associated with 0-g, an artificial gravity (AG) spacecraft offers many advantages and may indeed be an enabling technology for human flights to Mars. A number of important human factors must be taken into account in selecting the rotation radius, rotation rate, and orientation of the habitation module or modules. These factors include the gravity gradient effect, radial and tangential Coriolis forces, along with cross-coupled acceleration effects. Artificial gravity Mars transfer vehicle (MTV) concepts are presented that utilize both conventional NTR, as well as, enhanced bimodal nuclear thermal rocket (BNTR) propulsion. The NTR is a proven technology that generates high thrust and has a specific impulse (Isp) capability of approximately 900 s-twice that of today's best chemical rockets. The AG/MTV concepts using conventional Nuclear Thermal Propulsion (NTP) carry twin cylindrical International Space Station (ISS)- type habitation modules with their long axes oriented either perpendicular or parallel to the longitudinal spin axis of the MTV and utilize photovoltaic arrays (PVAs) for spacecraft power. The twin habitat modules are connected to a central operations hub located at the front of the MTV via two pressurized tunnels that provide the rotation radius for the habitat modules. For the BNTR AG/MTV option, each engine has its own closed secondary helium(He)-xenon (Xe) gas loop and Brayton Rotating Unit (BRU) that can generate 10s of kilowatts (kWe) of spacecraft electrical power during the mission coast phase

  9. The changing face of orthostatic and neurocardiogenic syncope with age.

    Science.gov (United States)

    Cooke, J; Carew, S; Costelloe, A; Sheehy, T; Quinn, C; Lyons, D

    2011-08-01

    Reports of the outcomes of syncope assessment across a broad spectrum of ages in a single population are scarce. It is our objective to chart the varying prevalence of orthostatic and neurocardiogenic syncope (NCS) as a patient ages. This was a retrospective study. All consecutive patients referred to a tertiary referral syncope unit over a decade were included. Patients were referred with recurrent falls or orthostatic intolerance. Tilt tests and carotid sinus massage (CSM) were performed in accordance with best practice guidelines. A total of 3002 patients were included (1451 short tilt, 127 active stand, 1042 CSM and 382 prolonged tilt). Ages ranged from 11 to 91 years with a median (IQR) of 75 (62-81) years. There were 1914 females; 1088 males. Orthostatic hypotension (OH) was the most commonly observed abnormality (test positivity of 60.3%). Those with OH had a median (IQR) age of 78 (71-83) years. Symptomatic patients were significantly younger than asymptomatic (P = 0.03). NCS demonstrated a bimodal age distribution. Of 194 patients with carotid sinus hypersensitivity, the median age (IQR) was 77 (68-82) years. Those with vasovagal syncope (n = 80) had a median (IQR) age of 30 (19-44) years. There were 57 patients with isolated postural orthostatic tachycardia syndrome. Of the total patients, 75% were female. They had a median (IQR) age of 23 (17-29) years. We have confirmed, in a single population, a changing pattern in the aetiology of syncope as a person ages. The burden of disease is greatest in the elderly.

  10. The changing face of orthostatic and neurocardiogenic syncope with age.

    LENUS (Irish Health Repository)

    Cooke, J

    2012-01-31

    AIM: Reports of the outcomes of syncope assessment across a broad spectrum of ages in a single population are scarce. It is our objective to chart the varying prevalence of orthostatic and neurocardiogenic syncope (NCS) as a patient ages. METHODS: This was a retrospective study. All consecutive patients referred to a tertiary referral syncope unit over a decade were included. Patients were referred with recurrent falls or orthostatic intolerance. Tilt tests and carotid sinus massage (CSM) were performed in accordance with best practice guidelines. RESULTS: A total of 3002 patients were included (1451 short tilt, 127 active stand, 1042 CSM and 382 prolonged tilt). Ages ranged from 11 to 91 years with a median (IQR) of 75 (62-81) years. There were 1914 females; 1088 males. Orthostatic hypotension (OH) was the most commonly observed abnormality (test positivity of 60.3%). Those with OH had a median (IQR) age of 78 (71-83) years. Symptomatic patients were significantly younger than asymptomatic (P = 0.03). NCS demonstrated a bimodal age distribution. Of 194 patients with carotid sinus hypersensitivity, the median age (IQR) was 77 (68-82) years. Those with vasovagal syncope (n = 80) had a median (IQR) age of 30 (19-44) years. There were 57 patients with isolated postural orthostatic tachycardia syndrome. Of the total patients, 75% were female. They had a median (IQR) age of 23 (17-29) years. CONCLUSION: We have confirmed, in a single population, a changing pattern in the aetiology of syncope as a person ages. The burden of disease is greatest in the elderly.

  11. Hendra Virus Spillover is a Bimodal System Driven by Climatic Factors.

    Science.gov (United States)

    Martin, Gerardo; Yanez-Arenas, Carlos; Plowright, Raina K; Chen, Carla; Roberts, Billie; Skerratt, Lee F

    2018-01-18

    Understanding environmental factors driving spatiotemporal patterns of disease can improve risk mitigation strategies. Hendra virus (HeV), discovered in Australia in 1994, spills over from bats (Pteropus sp.) to horses and thence to humans. Below latitude - 22°, almost all spillover events to horses occur during winter, and above this latitude spillover is aseasonal. We generated a statistical model of environmental drivers of HeV spillover per month. The model reproduced the spatiotemporal pattern of spillover risk between 1994 and 2015. The model was generated with an ensemble of methods for presence-absence data (boosted regression trees, random forests and logistic regression). Presences were the locations of horse cases, and absences per spatial unit (2.7 × 2.7 km pixels without spillover) were sampled with the horse census of Queensland and New South Wales. The most influential factors indicate that spillover is associated with both cold-dry and wet conditions. Bimodal responses to several variables suggest spillover involves two systems: one above and one below a latitudinal area close to - 22°. Northern spillovers are associated with cold-dry and wet conditions, and southern with cold-dry conditions. Biologically, these patterns could be driven by immune or behavioural changes in response to food shortage in bats and horse husbandry. Future research should look for differences in these traits between seasons in the two latitudinal regions. Based on the predicted risk patterns by latitude, we recommend enhanced preventive management for horses from March to November below latitude 22° south.

  12. Bimodal Biometric Verification Using the Fusion of Palmprint and Infrared Palm-Dorsum Vein Images

    Directory of Open Access Journals (Sweden)

    Chih-Lung Lin

    2015-12-01

    Full Text Available In this paper, we present a reliable and robust biometric verification method based on bimodal physiological characteristics of palms, including the palmprint and palm-dorsum vein patterns. The proposed method consists of five steps: (1 automatically aligning and cropping the same region of interest from different palm or palm-dorsum images; (2 applying the digital wavelet transform and inverse wavelet transform to fuse palmprint and vein pattern images; (3 extracting the line-like features (LLFs from the fused image; (4 obtaining multiresolution representations of the LLFs by using a multiresolution filter; and (5 using a support vector machine to verify the multiresolution representations of the LLFs. The proposed method possesses four advantages: first, both modal images are captured in peg-free scenarios to improve the user-friendliness of the verification device. Second, palmprint and vein pattern images are captured using a low-resolution digital scanner and infrared (IR camera. The use of low-resolution images results in a smaller database. In addition, the vein pattern images are captured through the invisible IR spectrum, which improves antispoofing. Third, since the physiological characteristics of palmprint and vein pattern images are different, a hybrid fusing rule can be introduced to fuse the decomposition coefficients of different bands. The proposed method fuses decomposition coefficients at different decomposed levels, with different image sizes, captured from different sensor devices. Finally, the proposed method operates automatically and hence no parameters need to be set manually. Three thousand palmprint images and 3000 vein pattern images were collected from 100 volunteers to verify the validity of the proposed method. The results show a false rejection rate of 1.20% and a false acceptance rate of 1.56%. It demonstrates the validity and excellent performance of our proposed method comparing to other methods.

  13. Bimodal Biometric Verification Using the Fusion of Palmprint and Infrared Palm-Dorsum Vein Images.

    Science.gov (United States)

    Lin, Chih-Lung; Wang, Shih-Hung; Cheng, Hsu-Yung; Fan, Kuo-Chin; Hsu, Wei-Lieh; Lai, Chin-Rong

    2015-12-12

    In this paper, we present a reliable and robust biometric verification method based on bimodal physiological characteristics of palms, including the palmprint and palm-dorsum vein patterns. The proposed method consists of five steps: (1) automatically aligning and cropping the same region of interest from different palm or palm-dorsum images; (2) applying the digital wavelet transform and inverse wavelet transform to fuse palmprint and vein pattern images; (3) extracting the line-like features (LLFs) from the fused image; (4) obtaining multiresolution representations of the LLFs by using a multiresolution filter; and (5) using a support vector machine to verify the multiresolution representations of the LLFs. The proposed method possesses four advantages: first, both modal images are captured in peg-free scenarios to improve the user-friendliness of the verification device. Second, palmprint and vein pattern images are captured using a low-resolution digital scanner and infrared (IR) camera. The use of low-resolution images results in a smaller database. In addition, the vein pattern images are captured through the invisible IR spectrum, which improves antispoofing. Third, since the physiological characteristics of palmprint and vein pattern images are different, a hybrid fusing rule can be introduced to fuse the decomposition coefficients of different bands. The proposed method fuses decomposition coefficients at different decomposed levels, with different image sizes, captured from different sensor devices. Finally, the proposed method operates automatically and hence no parameters need to be set manually. Three thousand palmprint images and 3000 vein pattern images were collected from 100 volunteers to verify the validity of the proposed method. The results show a false rejection rate of 1.20% and a false acceptance rate of 1.56%. It demonstrates the validity and excellent performance of our proposed method comparing to other methods.

  14. Bimodal Biometric Verification Using the Fusion of Palmprint and Infrared Palm-Dorsum Vein Images

    Science.gov (United States)

    Lin, Chih-Lung; Wang, Shih-Hung; Cheng, Hsu-Yung; Fan, Kuo-Chin; Hsu, Wei-Lieh; Lai, Chin-Rong

    2015-01-01

    In this paper, we present a reliable and robust biometric verification method based on bimodal physiological characteristics of palms, including the palmprint and palm-dorsum vein patterns. The proposed method consists of five steps: (1) automatically aligning and cropping the same region of interest from different palm or palm-dorsum images; (2) applying the digital wavelet transform and inverse wavelet transform to fuse palmprint and vein pattern images; (3) extracting the line-like features (LLFs) from the fused image; (4) obtaining multiresolution representations of the LLFs by using a multiresolution filter; and (5) using a support vector machine to verify the multiresolution representations of the LLFs. The proposed method possesses four advantages: first, both modal images are captured in peg-free scenarios to improve the user-friendliness of the verification device. Second, palmprint and vein pattern images are captured using a low-resolution digital scanner and infrared (IR) camera. The use of low-resolution images results in a smaller database. In addition, the vein pattern images are captured through the invisible IR spectrum, which improves antispoofing. Third, since the physiological characteristics of palmprint and vein pattern images are different, a hybrid fusing rule can be introduced to fuse the decomposition coefficients of different bands. The proposed method fuses decomposition coefficients at different decomposed levels, with different image sizes, captured from different sensor devices. Finally, the proposed method operates automatically and hence no parameters need to be set manually. Three thousand palmprint images and 3000 vein pattern images were collected from 100 volunteers to verify the validity of the proposed method. The results show a false rejection rate of 1.20% and a false acceptance rate of 1.56%. It demonstrates the validity and excellent performance of our proposed method comparing to other methods. PMID:26703596

  15. A Crewed Mission to Apophis Using a Hybrid Bimodal Nuclear Thermal Electric Propulsion (BNTEP) System

    Science.gov (United States)

    Mccurdy, David R.; Borowski, Stanley K.; Burke, Laura M.; Packard, Thomas W.

    2014-01-01

    A BNTEP system is a dual propellant, hybrid propulsion concept that utilizes Bimodal Nuclear Thermal Rocket (BNTR) propulsion during high thrust operations, providing 10's of kilo-Newtons of thrust per engine at a high specific impulse (Isp) of 900 s, and an Electric Propulsion (EP) system during low thrust operations at even higher Isp of around 3000 s. Electrical power for the EP system is provided by the BNTR engines in combination with a Brayton Power Conversion (BPC) closed loop system, which can provide electrical power on the order of 100's of kWe. High thrust BNTR operation uses liquid hydrogen (LH2) as reactor coolant propellant expelled out a nozzle, while low thrust EP uses high pressure xenon expelled by an electric grid. By utilizing an optimized combination of low and high thrust propulsion, significant mass savings over a conventional NTR vehicle can be realized. Low thrust mission events, such as midcourse corrections (MCC), tank settling burns, some reaction control system (RCS) burns, and even a small portion at the end of the departure burn can be performed with EP. Crewed and robotic deep space missions to a near Earth asteroid (NEA) are best suited for this hybrid propulsion approach. For these mission scenarios, the Earth return V is typically small enough that EP alone is sufficient. A crewed mission to the NEA Apophis in the year 2028 with an expendable BNTEP transfer vehicle is presented. Assembly operations, launch element masses, and other key characteristics of the vehicle are described. A comparison with a conventional NTR vehicle performing the same mission is also provided. Finally, reusability of the BNTEP transfer vehicle is explored.

  16. Bimodal Fuzzy Analytic Hierarchy Process (BFAHP) For Coronary Heart Disease Risk Assessment.

    Science.gov (United States)

    Sabahi, Farnaz

    2018-04-03

    Rooted deeply in medical multiple criteria decision-making (MCDM), risk assessment is very important especially when applied to the risk of being affected by deadly diseases such as coronary heart disease (CHD). CHD risk assessment is a stochastic, uncertain, and highly dynamic process influenced by various known and unknown variables. In recent years, there has been a great interest in fuzzy analytic hierarchy process (FAHP), a popular methodology for dealing with uncertainty in MCDM. This paper proposes a new FAHP, bimodal fuzzy analytic hierarchy process (BFAHP) that augments two aspects of knowledge, probability and validity, to fuzzy numbers to better deal with uncertainty. In BFAHP, fuzzy validity is computed by aggregating the validities of relevant risk factors based on expert knowledge and collective intelligence. By considering both soft and statistical data, we compute the fuzzy probability of risk factors using the Bayesian formulation. In BFAHP approach, these fuzzy validities and fuzzy probabilities are used to construct a reciprocal comparison matrix. We then aggregate fuzzy probabilities and fuzzy validities in a pairwise manner for each risk factor and each alternative. BFAHP decides about being affected and not being affected by ranking of high and low risks. For evaluation, the proposed approach is applied to the risk of being affected by CHD using a real dataset of 152 patients of Iranian hospitals. Simulation results confirm that adding validity in a fuzzy manner can accrue more confidence of results and clinically useful especially in the face of incomplete information when compared with actual results. Applying the proposed BFAHP on CHD risk assessment of the dataset, it yields high accuracy rate above 85% for correct prediction. In addition, this paper recognizes that the risk factors of diastolic blood pressure in men and high-density lipoprotein in women are more important in CHD than other risk factors. Copyright © 2018 Elsevier Inc. All

  17. First results from the IllustrisTNG simulations: the galaxy colour bimodality

    Science.gov (United States)

    Nelson, Dylan; Pillepich, Annalisa; Springel, Volker; Weinberger, Rainer; Hernquist, Lars; Pakmor, Rüdiger; Genel, Shy; Torrey, Paul; Vogelsberger, Mark; Kauffmann, Guinevere; Marinacci, Federico; Naiman, Jill

    2018-03-01

    We introduce the first two simulations of the IllustrisTNG project, a next generation of cosmological magnetohydrodynamical simulations, focusing on the optical colours of galaxies. We explore TNG100, a rerun of the original Illustris box, and TNG300, which includes 2 × 25003 resolution elements in a volume 20 times larger. Here, we present first results on the galaxy colour bimodality at low redshift. Accounting for the attenuation of stellar light by dust, we compare the simulated (g - r) colours of 109 simulation, as well as excellent quantitative agreement with the observations, with a sharp transition in median colour from blue to red at a characteristic M⋆ ˜ 1010.5 M⊙. Investigating the build-up of the colour-mass plane and the formation of the red sequence, we demonstrate that the primary driver of galaxy colour transition is supermassive black hole feedback in its low accretion state. Across the entire population the median colour transition time-scale Δtgreen is ˜1.6 Gyr, a value which drops for increasingly massive galaxies. We find signatures of the physical process of quenching: at fixed stellar mass, redder galaxies have lower star formation rates, gas fractions, and gas metallicities; their stellar populations are also older and their large-scale interstellar magnetic fields weaker than in bluer galaxies. Finally, we measure the amount of stellar mass growth on the red sequence. Galaxies with M⋆ > 1011 M⊙ which redden at z < 1 accumulate on average ˜25 per cent of their final z = 0 mass post-reddening; at the same time, ˜18 per cent of such massive galaxies acquire half or more of their final stellar mass while on the red sequence.

  18. The spatial distribution of age-related white matter changes as a function of vascular risk factors--results from the LADIS study

    DEFF Research Database (Denmark)

    Rostrup, E; Gouw, A A; Vrenken, H

    2012-01-01

    associations were found for age, gender and hypertension. Different distribution patterns were found for men and women. Further, increased probability was found in association with self-reported alcohol and tobacco consumption, as well as in those with a history of migraine. It is concluded that the location...... logistic regression, and validate the method using simulated datasets. The method was then applied in a total of 605 participants of the LADIS study (age 74 ± 5 years, all with WMH), and the location of manually delineated WMH was investigated after spatial normalisation. Particularly strong and widespread...... of WMH is dependent on the risk factors involved pointing towards a regionally different pathogenesis and/or vulnerability of the white matter....

  19. Weight-for-age standard score - distribution and effect on in-hospital mortality: A retrospective analysis in pediatric cardiac surgery

    Directory of Open Access Journals (Sweden)

    Antony George

    2015-01-01

    Full Text Available Objective: To study the distribution of weight for age standard score (Z score in pediatric cardiac surgery and its effect on in-hospital mortality. Introduction: WHO recommends Standard Score (Z score to quantify and describe anthropometric data. The distribution of weight for age Z score and its effect on mortality in congenital heart surgery has not been studied. Methods: All patients of younger than 5 years who underwent cardiac surgery from July 2007 to June 2013, under single surgical unit at our institute were enrolled. Z score for weight for age was calculated. Patients were classified according to Z score and mortality across the classes was compared. Discrimination and calibration of the for Z score model was assessed. Improvement in predictability of mortality after addition of Z score to Aristotle Comprehensive Complexity (ACC score was analyzed. Results: The median Z score was -3.2 (Interquartile range -4.24 to -1.91] with weight (mean±SD of 8.4 ± 3.38 kg. Overall mortality was 11.5%. 71% and 52.59% of patients had Z score < -2 and < -3 respectively. Lower Z score classes were associated with progressively increasing mortality. Z score as continuous variable was associated with O.R. of 0.622 (95% CI- 0.527 to 0.733, P < 0.0001 for in-hospital mortality and remained significant predictor even after adjusting for age, gender, bypass duration and ACC score. Addition of Z score to ACC score improved its predictability for in-hosptial mortality (δC - 0.0661 [95% CI - 0.017 to 0.0595, P = 0.0169], IDI- 3.83% [95% CI - 0.017 to 0.0595, P = 0.00042]. Conclusion: Z scores were lower in our cohort and were associated with in-hospital mortality. Addition of Z score to ACC score significantly improves predictive ability for in-hospital mortality.

  20. Changing distribution and geometry of S′ in Al–Cu–Mg single crystals during stress aging by controlling the loading orientation

    International Nuclear Information System (INIS)

    Chen, Jiqiang; Chen, Zhiguo; Guo, Xiaobin; Deng, Yunlai

    2016-01-01

    The precipitation behavior of S′ phase in Al–Cu–Mg single crystals during stress-free and stress aging was investigated by transmission electron microscopy (TEM). Different compressive stress magnitudes and loading orientations were applied to determine their effects on the precipitation of S′ in Al–Cu–Mg alloy during stress aging. The results indicate that a noticeable preferential orientation of S′ is generated in the sample under applied compressive stress of 33 MPa loading along close to [001] Al , whilst no obviously preferential orientation of S′ can be observed in the sample loaded along close to [101] Al under the same applied stress or even larger applied stress. The precipitation distribution of S′ phase during stress aging can be changed by the loading orientation of the applied stress. Moreover, compressive stress aging may lead to S′ phase shorter in length, and the length of S′ phase shows a decreasing tendency with increasing applied stress, which are associated with the positive misfit between S′ and Al matrix.

  1. Clear cell adenocarcinoma of the vagina and cervix. An update of the central Netherlands registry showing twin age incidence peaks.

    Science.gov (United States)

    Hanselaar, A; van Loosbroek, M; Schuurbiers, O; Helmerhorst, T; Bulten, J; Bernhelm, J

    1997-06-01

    The objective of this study was to update the registry of women in the Netherlands with clear cell adenocarcinoma (CCAC) of the cervix or vagina with or without intrauterine exposure to diethylstilbestrol (DES). From a nationwide search in PALGA, the automated pathology registry in the Netherlands, data were gathered on women with CCAC born after 1947. Information obtained from the clinical files of the patients included reported exposure to DES, patterns of complaints previous to diagnosis, the current status of the patients, and the results of cytopathologic examinations previous to histopathologic diagnosis. After review of the histopathologic slides, the specific pathologic characteristics of CCAC were determined. The age distribution of women born after 1947 was compared with that of women born before 1947. Information about possible exposure to DES during pregnancy was available for 73 of 88 women with CCAC born after 1947. Exposure to DES was reported for 47 (64%) of these women. The DES medication was most often reported as having started before the 18th week of pregnancy. Cytopathologic examination was informative in 81% of the cases of CCAC of the cervix, but only in 41% of the cases of CCAC of the vagina. Most patients had Stage I or II tumors at diagnosis. Tumor Stage III and IV and a high grade of nuclear atypia were related to unfavorable outcome. The age distribution of all patients with CCAC showed two distinct peaks; one at young age, (a mean age of 26 years), and one at older age (a mean age of 71 years). This bimodal age distribution still applied when the cases in which DES exposure was reported had been excluded. Despite the fact that DES has not been prescribed to pregnant women in the Netherlands in the last 20 years, CCAC is still relevant in our times. It is important to stay alert and periodically to update and evaluate the data of this registry, including data on women born outside the DES exposure period. The bimodal age distribution in

  2. Age, distribution, and significance within a sediment budget, of in-channel depositional surfaces in the Normanby River, Queensland, Australia

    Science.gov (United States)

    Pietsch, T. J.; Brooks, A. P.; Spencer, J.; Olley, J. M.; Borombovits, D.

    2015-06-01

    We present the results of investigations into alluvial deposition in the catchment of the Normanby River, which flows into Princess Charlotte Bay (PCB) in the northern part of the Great Barrier Reef Lagoon. Our focus is on the fine fraction (attached bars or inset or inner floodplains, these more or less flat-lying surfaces within the macro-channel have hitherto received little attention in sediment budgeting models. We use high resolution LiDAR based mapping combined with optical dating of exposures cut into these in-channel deposits to compare their aggradation rates with those found in other depositional zones in the catchment, namely the floodplain and coastal plain. In total 59 single grain OSL dates were produced across 21 stratigraphic profiles at 14 sites distributed though the 24 226 km2 catchment. In-channel storage in these inset features is a significant component of the contemporary fine sediment budget (i.e. recent decades/last century), annually equivalent to more than 50% of the volume entering the channel network from hillslopes and subsoil sources. Therefore, at the very least, in-channel storage of fine material needs to be incorporated into sediment budgeting exercises. Furthermore, deposition within the channel has occurred in multiple locations coincident in time with accelerated sediment production following European settlement. Generally, this has occurred on a subset of the features we have examined here, namely linear bench features low in the channel. This suggests that accelerated aggradation on in-channel depositional surfaces has been in part a response to accelerated erosion within the catchment. The entire contribution of ~ 370 kilotonnes per annum of fine sediment estimated to have been produced by alluvial gully erosion over the last ~ 100 years can be accounted for by that stored as in-channel alluvium. These features therefore can play an important role in mitigating the impact on the receiving water of accelerated erosion.

  3. Enabling data science in the Gaia mission archive: The present-day mass function and age distribution

    Science.gov (United States)

    Tapiador, D.; Berihuete, A.; Sarro, L. M.; Julbe, F.; Huedo, E.

    2017-04-01

    Recent advances in large scale computing architectures enable new opportunities to extract value out of the vast amounts of data being currently generated. However, their successful adoption is not straightforward in areas like science, as there are still some barriers that need to be overcome. Those comprise (i) the existence of legacy code that needs to be ported, (ii) the lack of high-level and use case specific frameworks that facilitate a smoother transition, or (iii) the scarcity of profiles with the balanced skill sets between the technological and scientific domains. The European Space Agency's Gaia mission will create the largest and most precise three dimensional chart of our galaxy (the Milky Way), providing unprecedented position, parallax and proper motion measurements for about one billion stars. The successful exploitation of this data archive will depend on the ability to offer the proper infrastructure upon which scientists will be able to do exploration and modelling with this huge data set. In this paper, we present and contextualize these challenges by building two probabilistic models using Hierarchical Bayesian Modelling. These models represent a key challenge in astronomy and are of paramount importance for the Gaia mission itself. Moreover, we approach the implementation by leveraging a generic distributed processing engine through an existing software package for Markov chain Monte Carlo sampling. The two computationally intensive models are then validated with simulated data in different scenarios under specific restrictions, and their performance is assessed to prove their scalability. We argue that this approach will not only serve for the models in hand but also for exemplifying how to address similar problems in science, which may need to both scale to bigger data sets and reuse existing software as much as possible. This will lead to shorter time to science in massive data archives.

  4. Age, distribution and style of deformation in Alaska north of 60°N: Implications for assembly of Alaska

    Science.gov (United States)

    Moore, Thomas E.; Box, Stephen E.

    2016-11-01

    The structural architecture of Alaska is the product of a complex history of deformation along both the Cordilleran and Arctic margins of North America involving oceanic plates, subduction zones and strike-slip faults and with continental elements of Laurentia, Baltica, and Siberia. We use geological constraints to assign regions of deformation to 14 time intervals and to map their distributions in Alaska. Alaska can be divided into three domains with differing deformational histories. Each domain includes a crustal fragment that originated near Early Paleozoic Baltica. The Northern domain experienced the Early Cretaceous Brookian orogeny, an oceanic arc-continent collision, followed by mid-Cretaceous extension. Early Cretaceous opening of the oceanic Canada Basin rifted the orogen from the Canadian Arctic margin, producing the bent trends of the orogen. The second (Southern) domain consists of Neoproterozoic and younger crust of the amalgamated Peninsular-Wrangellia-Alexander arc terrane and its paired Mesozoic accretionary prism facing the Pacific Ocean basin. The third (Interior) domain, situated between the first two domains and roughly bounded by the Cenozoic dextral Denali and Tintina faults, includes the large continental Yukon Composite and Farewell terranes having different Permian deformational episodes. Although a shared deformation that might mark their juxtaposition by collisional processes is unrecognized, sedimentary linkage between the two terranes and depositional overlap of the boundary with the Northern domain occurred by early Late Cretaceous. Late Late Cretaceous deformation is the first deformation shared by all three domains and correlates temporally with emplacement of the Southern domain against the remainder of Alaska. Early Cenozoic shortening is mild across interior Alaska but is significant in the Brooks Range, and correlates in time with dextral faulting, ridge subduction and counter-clockwise rotation of southern Alaska. Late Cenozoic

  5. Tissue, age, and sex distribution of thallium in shrews from Doñana, a protected area in SW Spain.

    Science.gov (United States)

    Sánchez-Chardi, Alejandro

    2007-09-20

    In 1998, the protected area of Doñana, an important natural region in SW Europe, was affected with great amount of acidic waters and sludge from a pyrite mine loaded with toxic metals such as thallium (Tl). Since this ecological catastrophe, several studies have addressed the effects of this pollution on the flora and fauna in this protected area. However, in contrast to other non-essential metals, scarce information on Tl was available after this disaster, especially in terrestrial environments. This study reported a 3- and 10-fold increase in Tl in liver and kidneys, respectively, of the greater white-toothed shrew, Crocidura russula, in the polluted site in comparison with reference animals. Kidneys showed the highest concentrations of this metal in the polluted site, whereas both organs analysed have similar concentrations in the reference site. Although no significant age-dependent variation was found, adults had higher concentrations than juveniles. Moreover, females showed higher concentrations than males. These results demonstrate the high entrance and transfer of Tl in terrestrial food-chains. To the best of my knowledge, these data constitute the first measurements of Tl in mammals from the protected area of Doñana and are among the few available for insectivorous mammals.

  6. Admixture analysis of age of onset in generalized anxiety disorder.

    Science.gov (United States)

    Rhebergen, Didi; Aderka, Idan M; van der Steenstraten, Ira M; van Balkom, Anton J L M; van Oppen, Patricia; Stek, Max L; Comijs, Hannie C; Batelaan, Neeltje M

    2017-08-01

    Age of onset is a marker of clinically relevant subtypes in various medical and psychiatric disorders. Past research has also reported that age of onset in generalized anxiety disorder (GAD) is clinically significant; but, in research to date, arbitrary cut-off ages have been used. In the present study, admixture analysis was used to determine the best fitting model for age of onset distribution in GAD. Data were derived from 459 adults with a diagnosis of GAD who took part in the Netherlands Study of Depression and Anxiety (NESDA). Associations between age of onset subtypes, identified by admixture analysis, and sociodemographic, clinical, and vulnerability factors were examined using univariate tests and multivariate logistic regression analyses. Two age of onset distributions were identified: an early-onset group (24 years of age and younger) and a late-onset group (greater than 24 years of age). Multivariate analysis revealed that early-onset GAD was associated with female gender (OR 2.1 (95%CI 1.4-3.2)), higher education (OR 1.1 (95%CI 1.0-1.2)), and higher neuroticism (OR 1.4 (95%CI 1.1-1.7)), while late-onset GAD was associated with physical illnesses (OR 1.3 (95%CI 1.1-1.7)). Study limitations include the possibility of recall bias given that age of onset was assessed retrospectively, and an inability to detect a possible very-late-onset GAD subtype. Collectively, the results of the study indicate that GAD is characterized by a bimodal age of onset distribution with an objectively determined early cut-off at 24 years of age. Early-onset GAD is associated with unique factors that may contribute to its aetiology; but, it does not constitute a more severe subtype compared to late-onset GAD. Future research should use 24 years of age as the cut-off for early-onset GAD to when examining the clinical relevance of age of onset for treatment efficacy and illness course. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. A bimodal neurophysiological study of motor control in attention-deficit hyperactivity disorder: a step towards core mechanisms?

    Science.gov (United States)

    Heinrich, Hartmut; Hoegl, Thomas; Moll, Gunther H; Kratz, Oliver

    2014-04-01

    Knowledge about the core neural mechanisms of attention-deficit hyperactivity disorder, a pathophysiologically heterogeneous psychiatric disorder starting in childhood, is still limited. Progress may be achieved by combining different methods and levels of investigation. In the present study, we investigated neural mechanisms of motor control in 19 children with attention-deficit hyperactivity disorder (aged 9-14 years) and 21 age-matched typically developing children by relating neural markers of attention and response control (using event-related potentials) and measures of motor excitability/inhibition (evoked by transcranial magnetic stimulation). Thus, an interplay of processes at a subsecond scale could be studied. Using a monetary incentives-based cued Go/No-Go task, parameters that are well-known to be reduced in attention-deficit hyperactivity disorder were analysed: event-related potential components P3 (following cue stimuli; in Go and No-Go trials) and contingent negative variation as well as the transcranial magnetic stimulation-based short-interval intracortical inhibition measured at different latencies in Go and No-Go trials. For patient and control groups, different associations were obtained between performance, event-related potential and transcranial magnetic stimulation measures. In children with attention-deficit hyperactivity disorder, the P3 amplitude in Go trials was not correlated with reaction time measures but with short-interval intracortical inhibition at rest (r=0.56, P=0.01). In No-Go trials, P3 and short-interval intracortical inhibition after inhibiting the response (at 500 ms post-stimulus) were correlated in these children only (r=0.62; P=0.008). A classification rate of 90% was achieved when using short-interval intracortical inhibition (measured shortly before the occurrence of a Go or No-Go stimulus) and the amplitude of the P3 in cue trials as input features in a linear discriminant analysis. Findings indicate deviant neural

  8. Polymer pipes for distributing mixtures of hydrogen and natural gas. Evolution of their transport and mechanical properties after an ageing under an hydrogen environment

    Energy Technology Data Exchange (ETDEWEB)

    Klopffer, Marie-Helene [IFP (France); Berne, Philippe [CEA (France); Castagnet, Sylvie [ENSMA (France); Weber, Mathilde [Air Liquide (Canada); Hochstetter, Gilles [Arkema (France); Espuche, Eliane [INSA Lyon (France)

    2010-07-01

    With the development of hydrogen as an energy vector, its delivery and transport from the production site to the end user remains an issue. Indeed, the key challenge to overcome is the high hydrogen permeation through existing polymer infrastructures used for natural gas distribution (Polyethylene pipes, components as connecting parts). This high flow rate of hydrogen through polymer has to be taken into account for safety and economical requirements. This 3-year project investigates pure hydrogen gas and mixtures (20% CH4 - 80% H2) in pipelines made of engineering polymers to develop and assess material solutions to cope with today problems for H2 distribution. Materials such as polyethylene (PE100) and polyamide 11 (PA11) have been studied. PE100 is considered as a reference material as it is used today in natural gas distribution pipes. PA11 should allow a higher operating pressure combined with better gas-barrier performances. Test benches and protocols for testing materials in terms of mechanical and barrier properties were first developed. The materials have then been studied in terms of barrier, mechanical properties and on a microstructural point of view. The properties of the raw material and samples after ageing in presence of hydrogen in various conditions were compared to assess the long term behaviour in service. These results as well as the comparison between PA11 and PE are presented. (orig.)

  9. Carbon Dynamics of a Boreal Logging Age Sequence in Northern Manitoba

    Science.gov (United States)

    Plaut, J.; Martin, J.; Weber, J.; Gower, S. T.

    2001-12-01

    Increasing pressure has been put on boreal forests to meet the growing demand for timber products. Boreal forests contain a disproportionately large amount of carbon in the soil and are believed to play an important role in carbon sequestration, but the effects of disturbance, such as harvesting, on the carbon budget are poorly understood. The objective of this study was to compare the carbon content and aboveground net primary production for a mixed species (Picea mariana, Pinus banksiana, and Populus tremuloides) boreal forest logging age sequence in northern Manitoba. The age sequence consisted of replicated, even-aged stands that originated from clear-cut harvests in 1990, 1983, 1971, and 1935. Carbon content of aboveground vegetation increased significantly during stand recovery, and was significantly greater than similar-aged black spruce stands recovering from wildfire. Distribution of coarse woody debris (CWD) was bimodal, with greater mass per hectare at the 1990 and 1935 sites, and a minimum at the 1971 site. Trends in CWD distribution, as well as forest floor carbon and soil carbon content are used to establish decomposition rates and consequences for the carbon budget.

  10. Variation in Carbon Storage and Its Distribution by Stand Age and Forest Type in Boreal and Temperate Forests in Northeastern China

    Science.gov (United States)

    Wei, Yawei; Li, Maihe; Chen, Hua; Lewis, Bernard J.; Yu, Dapao; Zhou, Li; Zhou, Wangming; Fang, Xiangmin; Zhao, Wei; Dai, Limin

    2013-01-01

    The northeastern forest region of China is an important component of total temperate and boreal forests in the northern hemisphere. But how carbon (C) pool size and distribution varies among tree, understory, forest floor and soil components, and across stand ages remains unclear. To address this knowledge gap, we selected three major temperate and two major boreal forest types in northeastern (NE) China. Within both forest zones, we focused on four stand age classes (young, mid-aged, mature and over-mature). Results showed that total C storage was greater in temperate than in boreal forests, and greater in older than in younger stands. Tree biomass C was the main C component, and its contribution to the total forest C storage increased with increasing stand age. It ranged from 27.7% in young to 62.8% in over-mature stands in boreal forests and from 26.5% in young to 72.8% in over-mature stands in temperate forests. Results from both forest zones thus confirm the large biomass C storage capacity of old-growth forests. Tree biomass C was influenced by forest zone, stand age, and forest type. Soil C contribution to total forest C storage ranged from 62.5% in young to 30.1% in over-mature stands in boreal and from 70.1% in young to 26.0% in over-mature in temperate forests. Thus soil C storage is a major C pool in forests of NE China. On the other hand, understory and forest floor C jointly contained less than 13% and forests respectively, and thus play a minor role in total forest C storage in NE China. PMID:23977252

  11. Influence of age on the passage of paraquat through the blood-brain barrier in rats: a distribution and pathological examination

    International Nuclear Information System (INIS)

    Widdowson, P.S.; Farnworth, M.J.; Simpson, M.G.; Lock, E.A.

    1996-01-01

    Experiments were performed to determine the extent of paraquat entry into the brain of neonatal and elderly rats, as compared with adult rats, which may be dependent on the efficacy of the blood-brain barrier. A single, median lethal dose (20 mg/kg s.c.) of paraquat containing [14C]paraquat was administered to neonatal (10 day old), adult (3 month old) and elderly (18 month old) rats. In contrast to the adult and elderly rats where paraquat levels fell over the 24 h post-dosing period to negligible levels, paraquat concentrations in neonatal brains did not decrease with time between 0.5 and 24 h following dosing. The distribution of [14C]paraquat was measured in selective brain regions using quantitative autoradiography in all three age groups of rats, 30 min and 24 h following dosing. Autoradiography demonstrated that brain paraquat distributions were similar in the rat age groups. Most of the paraquat was confined to regions outside the blood-brain barrier and to brain regions that lack a complete blood-brain barrier e.g. dorsal hypothalamus, area postrema and the anterior olfactory bulb. Between 0.5 h and 24 h following dosing, paraquat concentrations in deeper brain structures, some distance away from the sites of entry, began to slowly increase in all the rat age groups. By 24 h following dosing, a majority of brain regions examined using quantitative autoradiography revealed significantly higher paraquat concentrations in neonatal brains as compared to brain regions of adult and elderly rats. Despite increased paraquat entry into neonatal brain, we could find no evidence for paraquat-induced neuronal cell damage following a detailed histopathological examination of perfused-fixed brains. In conclusion, impaired blood-brain barrier integrity in neonatal brain thus permitting more paraquat to enter than in adult brain, did not result in neuronal damage

  12. Development of a Prototype Web GIS-Based Disaster Management System for Safe Operation of the Next Generation Bimodal Tram, South Korea—Focused Flooding and Snowfall

    Directory of Open Access Journals (Sweden)

    Won Seok Jang

    2014-04-01

    Full Text Available The Korea Railroad Research Institute (KRRI has developed a bimodal tram and advanced bus rapid transit (BRT system which is an optimized public transit system created by mixing the railway’s punctual operation and the bus’ easy and convenient access. The bimodal tram system provides mass-transportation service with an eco-friendly and human-centered approach. Natural disasters have been increasing worldwide in recent years, including floods, snow, and typhoons disasters. Flooding is the most frequent natural disaster in many countries and is increasingly a concern with climate change; it seriously affects people’s lives and productivity, causing considerable economic loss and significant damage. Enhanced conventional disaster management systems are needed to support comprehensive actions to secure safety and convenience. The objective of this study is to develop a prototype version of a Web GIS-based bimodal tram disaster management system (BTDMS using the Storm Water Management Model (SWMM 5.0 to enhance on-time operation and safety of the bimodal tram system. The BTDMS was tested at the bimodal tram test railroad by simulating probable maximum flood (PMF and snow melting for forecasting flooding and snow covered roads. This result could provide the basis for plans to protect against flooding disasters and snow covered roads in operating the bimodal tram system. The BTDMS will be used to assess and predict weather impacts on roadway conditions and operations and thus has the potential to influence economic growth. The methodology presented in this paper makes it possible to manage impacts of flooding and snowfall on urban transportation and enhance operation of the bimodal tram system. Such a methodology based on modeling could be created for most metropolitan areas in Korea and in many other countries.

  13. An atypical age-specific pattern of hepatocellular carcinoma in Peru: a threat for Andean populations.

    Science.gov (United States)

    Bertani, Stéphane; Pineau, Pascal; Loli, Sebastian; Moura, Julien; Zimic, Mirko; Deharo, Eric; Ruiz, Eloy

    2013-01-01

    In South America, the highest incidence of primary liver cancer is observed in Peru. However, national estimations on hepatocellular carcinoma incidence and mortality are approximated using aggregated data from surrounding countries. Thus, there is a lack of tangible information from Peru that impairs an accurate description of the local incidence, presentation, and outcomes of hepatocellular carcinoma. The present study attempts to fill this gap and assesses the clinical epidemiology of hepatocellular carcinoma in this country. A retrospective cohort study was conducted by analysing the medical charts of 1,541 patients with hepatocellular carcinoma admitted between 1997 and 2010 at the Peruvian national institute for cancer. The medical records including liver function, serologic status, and tumor pathology and stage were monitored. Statistical analyses were performed in order to characterize tumor presentation according to demographic features, risk factors, and regional origin. Surprisingly, the age distribution of the patient population displayed bimodality corresponding to two distinct age-based subpopulations. While an older group was in keeping with the age range observed for hepatocellular carcinoma around the world, a younger population displayed an abnormally juvenile mean age of 25.5 years old. In addition, each subpopulation displayed age-specific pathophysiological and clinical characteristics. The analysis suggests two different age-specific natural histories of hepatocellular carcinoma in the Peruvian patient population. This otherwise unusual tumor process that is ongoing in younger patients leads to the hypothesis that there may be a Peru-endemic risk factor driving hepatocarcinogenesis in the local population.

  14. [Analysis on geographic distribution of high blood pressure prevalence in children and adolescents aged 7-18 years in China, 2014].

    Science.gov (United States)

    Dong, Y H; Zou, Z Y; Wang, Z H; Wang, S; Yang, Z P; Chen, Y J; Ma, J

    2017-07-10

    Objective: To understand and evaluate the characteristics of geographic distribution of high blood pressure prevalence in children and adolescents aged 7-18 years in China in 2014, and provide evidence for the prevention of hypertension in children and adolescents. Methods: The data of 2014 Chinese National Surveys on Students Constitution and Health conducting 31 provinces (except Hong Kong, Macao and Taiwan) were collected. A total of 216 299 children and adolescents who had complete blood pressure records were selected as study subjects. The low, middle and high prevalence areas were identified according to their high blood pressure detection rates in the children and adolescents,7 % , to analyze the geographic distribution of high blood pressure prevalence in the children and adolescents. The environmental data in the capitals of 31 provinces in 2014 were collected to analyze the correlation between environmental factors and blood pressure Z score in the children and adolescents. Results: The average detection rates of high blood pressure was 6.4 % in 31 provinces (1.5 % -14.2 % ). The high prevalence areas were mainly distributed in the eastern China, especially the Circum-Bohai sea area, low prevalence areas were mainly distributed in the central and western areas of China and some provinces in the east. Correlation analysis results showed that the annual average temperature, annual average air humidity and local altitude were negatively correlated with blood pressure Z score, including diastolic and systolic blood pressure, in both boys and girls. The annual average sunshine time, PM(2.5) and PM(10) concentrations, content of SO(2) were positively correlated with blood pressure Z score in both boys and girls. Conclusions: There was a significant difference in high blood pressure of children and adolescents among 31 provinces. More attention should be paid to the children and adolescents living high prevalence area. And it is necessary to understand

  15. Magnetically engineered SnO2 quantum dots as a bimodal agent for optical and magnetic resonance imaging

    Science.gov (United States)

    Dutta, Dipa; Gupta, Jagriti; Thakur, Dinbandhu; Bahadur, Dhirendra

    2017-12-01

    Combining more than one imaging technique into a single system can outweigh the limitations of conventional imaging techniques. Pairing optically active quantum dots (QDs) with superparamagnetic MRI agent is an adorable way to develop probes for bimodal imaging. Tiny SnO2 quantum dot embedded iron oxide (IO) nanocomposite (SQD-IO) is synthesized. This combines the superparamagnetic property of IO nanoparticles (NPs) and special optical properties of SnO2 QDs, and is explored as a bimodal imaging agent. Morphological studies of the nanocomposite reveal that 3 nm tiny SnO2 QDs are embedded in ~30 nm γ-Fe2O3 NPs. The SQD-IO preserves the intrinsic superparamagnetic behaviour of its constituent IO NPs with a magnetization ~21.4 emu g‑1 measured at an applied field of 20k Oe. The emission colour of the nanocomposite is tuned by simply varying the excitation wavelength. The centre of the emission band shifts from 570 to 600 nm as the excitation alters from 488 to 535 nm. The cytotoxicity assessment indicates that the nanocomposite is suitable for its in vitro use. Transverse proton relaxivity (141 mM‑1 s‑1) of the nanocomposite is higher than the widely used negative contrast agent Feridex (R2  =  98.3 mM‑1 s‑1). The confocal laser scanning microscope images give evidence of the cellular uptake behaviour of SQD-IO in HeLa cells and it is seen that QDs retain their optical properties within the intracellular environment. The high R2 value for MRI and the tunable florescence images of HeLa cells essentially establish SQD-IO as a potential probe for bimodal imaging.

  16. Impact of the aging process of black carbon aerosols on their spatial distribution, hygroscopicity, and radiative forcing in a global climate model

    Science.gov (United States)

    Goto, D.; Oshima, N.; Nakajima, T.; Takemura, T.; Ohara, T.

    2012-11-01

    Black carbon (BC) absorbs shortwave radiation more strongly than any other type of aerosol, and an accurate simulation of the aging processes of BC-containing particle is required to properly predict aerosol radiative forcing (ARF) and climate change. However, BC aging processes have been simplified in general circulation models (GCMs) due to limited computational resources. In particular, differences in the representation of the mixing states of BC-containing particles between GCMs constitute one of main reasons for the uncertainty in ARF estimates. To understand an impact of the BC aging processes and the mixing state of BC on the spatial distribution of BC and ARF caused by BC (BC-ARF), we implemented three different methods of incorporating BC aging processes into a global aerosol transport model, SPRINTARS: (1) the "AGV" method, using variable conversion rates of BC aging based on a new type of parameterization depending on both BC amount and sulfuric acid; (2) the "AGF" method, using a constant conversion rate used worldwide in GCMs; and (3) the "ORIG" method, which is used in the original SPRINTARS. First, we found that these different methods produced different BC burden within 10% over industrial areas and 50% over remote oceans. Second, a ratio of water-insoluble BC to total BC (WIBC ratio) was very different among the three methods. Near the BC source region, for example, the WIBC ratios were estimated to be 80-90% (AGV and AGF) and 50-60% (ORIG). Third, although the BC aging process in GCMs had small impacts on the BC burden, they had a large impact on BC-ARF through a change in both the WIBC ratio and non-BC compounds coating on BC cores. As a result, possible differences in the treatment of the BC aging process between aerosol modeling studies can produce a difference of approximately 0.3 Wm-2 in the magnitude of BC-ARF, which is comparable to the uncertainty suggested by results from a global aerosol modeling intercomparison project, AeroCom. The

  17. Temporal and spatial distribution of Paleozoic metamorphism in the southern Appalachian Blue Ridge and Inner Piedmont delimited by ion microprobe U-Pb ages of metamorphic zircon

    Science.gov (United States)

    Merschat, Arthur J.; Bream, Brendan R.; Huebner, Matthew T.; Hatcher, Robert D.; Miller, Calvin F.

    2017-01-01

    Ion microprobe U-Pb zircon rim ages from 39 samples from across the accreted terranes of the central Blue Ridge, eastward across the Inner Piedmont, delimit the timing and spatial extent of superposed metamorphism in the southern Appalachian orogen. Metamorphic zircon rims are 10–40 µm wide, mostly unzoned, and dark gray to black or bright white in cathodoluminescence, and truncate and/or embay interior oscillatory zoning. Black unzoned and rounded or ovoid-shaped metamorphic zircon morphologies also occur. Th/U values range from 0.01 to 1.4, with the majority of ratios less than 0.1. Results of 206Pb/238U ages, ±2% discordant, range from 481 to 305 Ma. Clustering within these data reveals that the Blue Ridge and Inner Piedmont terranes were affected by three tectonothermal events: (1) 462–448 Ma (Taconic); (2) 395–340 Ma (Acadian and Neoacadian); and (3) 335–322 Ma, related to the early phase of the Alleghanian orogeny. By combining zircon rim ages with metamorphic isograds and other published isotopic ages, we identify the thermal architecture of the southern Appalachian orogen: juxtaposed and superposed metamorphic domains have younger ages to the east related to the marginward addition of terranes, and these domains can serve as a proxy to delimit terrane accretion. Most 462–448 Ma ages occur in the western and central Blue Ridge and define a continuous progression from greenschist to granulite facies that identifies the intact Taconic core. The extent of 462–448 Ma metamorphism indicates that the central Blue Ridge and Tugaloo terranes were accreted to the western Blue Ridge during the Taconic orogeny. Zircon rim ages in the Inner Piedmont span almost 100 m.y., with peaks at 395–385, 376–340, and 335–322 Ma, and delimit the Acadian-Neoacadian and Alleghanian metamorphic core. The timing and distribution of metamorphism in the Inner Piedmont are consistent with the Devonian to Mississippian oblique collision of the Carolina superterrane

  18. The Model Analysis of a Complex Tuning Fork Probe and Its Application in Bimodal Atomic Force Microscopy

    Directory of Open Access Journals (Sweden)

    Zhichao Wu

    2017-01-01

    Full Text Available A new electromechanical coupling model was built to quantitatively analyze the tuning fork probes, especially the complex ones. A special feature of a novel, soft tuning fork probe, that the second eigenfrequency of the probe was insensitive to the effective force gradient, was found and used in a homemade bimodal atomic force microscopy to measure power dissipation quantitatively. By transforming the mechanical parameters to the electrical parameters, a monotonous and concise method without using phase to calculate the power dissipation was proposed.

  19. Thermal Aging Effects on Residual Stress and Residual Strain Distribution on Heat Affected Zone of Alloy 600 in Dissimilar Metal Weld

    International Nuclear Information System (INIS)

    Ham, Junhyuk; Choi, Kyoung Joon; Kim, Ji Hyun

    2016-01-01

    Dissimilar metal weld (DMW), consisting of Alloy 600, Alloy 182, and A508 Gr.3, has been widely used as a joining material of the reactor pressure vessel penetration nozzle and the steam generator tubing for pressurized water reactors (PWR) because of its good mechanical strength, thermal conductivity, and corrosion resistance. Residual tensile stress is mainly nominated as a cause of SCC in light water reactors by IAEA report. So, to relax the residual stress, post-weld heat treatment is required after manufacturing process such as welding. However, thermal treatment has a great effect on the microstructure and the chromium depletion profile on Alloy 600, so called sensitization. By this reason, HAZ on Alloy 600 is critical to crack. According to G.A. Young et al., Crack growth rates (CGR) in the Alloy 600 HAZ were about 30 times faster than those in the Alloy 600 base metal tested under the same conditions. And according to Z.P. Lu et al., CGR in the Alloy 600 HAZ can be more than 20 times higher than that in its base metal. There are some methods to measure the exact value of residual stress on the material surface. The most common way is X-ray diffraction method (XRD). The principle of XRD is based on lattice strains and depends on the changes in the spacing of the atomic planes in material. And there is a computer simulation method to estimate residual stress distribution which is called ANSYS. This study was conducted to investigate how thermal aging affects residual stress and residual strain distribution of Alloy 600 HAZ. Following conclusions can be drawn from this study. According to preceding researches and this study, both the relaxation of residual stress and the change of residual strain follow as similar way, spreading out from concentrated region. The result of Vickers micro-hardness tester shows that tensile residual stresses are distributed broadly on the material aged by 15 years. Therefore, HT400 Y 15 material is weakest state for PWSCC. The

  20. Does Glycosylation as a modifier of Original Antigenic Sin explain the case age distribution and unusual toxicity in pandemic novel H1N1 influenza?

    Directory of Open Access Journals (Sweden)

    Nishiura Hiroshi

    2010-01-01

    Full Text Available Abstract Background A pandemic novel H1N1 swine-origin influenza virus has emerged. Most recently the World Health Organization has announced that in a country-dependent fashion, up to 15% of cases may require hospitalization, often including respiratory support. It is now clear that healthy children and young adults are disproportionately affected, most unusually among those with severe respiratory disease without underlying conditions. One possible explanation for this case age distribution is the doctrine of Original Antigenic Sin, i.e., novel H1N1 may be antigenically similar to H1N1 viruses that circulated at an earlier time. Persons whose first exposure to influenza viruses was to such similar viruses would be relatively immune. However, this principle is not sufficient to explain the graded susceptibility between ages 20 and 60, the reduced susceptibility in children below age 10, and the unusual toxicity observed. Methods We collected case data from 11 countries, about 60% of all cases reported through mid-July 2009. We compared sequence data for the hemagglutinin of novel H1N1 with sequences of H1N1 viruses from 1918 to the present. We searched for sequence differences that imply loss of antigenicity either directly through amino acid substitution or by the appearance of sites for potential glycosylation proximal to sites known to be antigenic in humans. We also considered T-cell epitopes. Results In our composite, over 75% of confirmed cases of novel H1N1 occurred in persons ≤ 30 years old, with peak incidence in the age range 10-19 years. Less than 3% of cases occurred in persons over 65, with a gradation in incidence between ages 20 and 60 years. The sequence data indicates that novel H1N1 is most similar to H1N1 viruses that circulated before 1943. Novel H1N1 lacks glycosylation sites on the globular head of hemagglutinin (HA1 near