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Sample records for age distribution similar

  1. Bilateral Trade Flows and Income Distribution Similarity.

    PubMed

    Martínez-Zarzoso, Inmaculada; Vollmer, Sebastian

    2016-01-01

    Current models of bilateral trade neglect the effects of income distribution. This paper addresses the issue by accounting for non-homothetic consumer preferences and hence investigating the role of income distribution in the context of the gravity model of trade. A theoretically justified gravity model is estimated for disaggregated trade data (Dollar volume is used as dependent variable) using a sample of 104 exporters and 108 importers for 1980-2003 to achieve two main goals. We define and calculate new measures of income distribution similarity and empirically confirm that greater similarity of income distribution between countries implies more trade. Using distribution-based measures as a proxy for demand similarities in gravity models, we find consistent and robust support for the hypothesis that countries with more similar income-distributions trade more with each other. The hypothesis is also confirmed at disaggregated level for differentiated product categories.

  2. Bilateral Trade Flows and Income Distribution Similarity

    PubMed Central

    2016-01-01

    Current models of bilateral trade neglect the effects of income distribution. This paper addresses the issue by accounting for non-homothetic consumer preferences and hence investigating the role of income distribution in the context of the gravity model of trade. A theoretically justified gravity model is estimated for disaggregated trade data (Dollar volume is used as dependent variable) using a sample of 104 exporters and 108 importers for 1980–2003 to achieve two main goals. We define and calculate new measures of income distribution similarity and empirically confirm that greater similarity of income distribution between countries implies more trade. Using distribution-based measures as a proxy for demand similarities in gravity models, we find consistent and robust support for the hypothesis that countries with more similar income-distributions trade more with each other. The hypothesis is also confirmed at disaggregated level for differentiated product categories. PMID:27137462

  3. Bilateral Trade Flows and Income Distribution Similarity.

    PubMed

    Martínez-Zarzoso, Inmaculada; Vollmer, Sebastian

    2016-01-01

    Current models of bilateral trade neglect the effects of income distribution. This paper addresses the issue by accounting for non-homothetic consumer preferences and hence investigating the role of income distribution in the context of the gravity model of trade. A theoretically justified gravity model is estimated for disaggregated trade data (Dollar volume is used as dependent variable) using a sample of 104 exporters and 108 importers for 1980-2003 to achieve two main goals. We define and calculate new measures of income distribution similarity and empirically confirm that greater similarity of income distribution between countries implies more trade. Using distribution-based measures as a proxy for demand similarities in gravity models, we find consistent and robust support for the hypothesis that countries with more similar income-distributions trade more with each other. The hypothesis is also confirmed at disaggregated level for differentiated product categories. PMID:27137462

  4. Age Distribution of Groundwater

    NASA Astrophysics Data System (ADS)

    Morgenstern, U.; Daughney, C. J.

    2012-04-01

    Groundwater at the discharge point comprises a mixture of water from different flow lines with different travel time and therefore has no discrete age but an age distribution. The age distribution can be assessed by measuring how a pulse shaped tracer moves through the groundwater system. Detection of the time delay and the dispersion of the peak in the groundwater compared to the tracer input reveals the mean residence time and the mixing parameter. Tritium from nuclear weapons testing in the early 1960s resulted in a peak-shaped tritium input to the whole hydrologic system on earth. Tritium is the ideal tracer for groundwater because it is an isotope of hydrogen and therefore is part of the water molecule. Tritium time series data that encompass the passage of the bomb tritium pulse through the groundwater system in all common hydrogeologic situations in New Zealand demonstrate a semi-systematic pattern between age distribution parameters and hydrologic situation. The data in general indicate high fraction of mixing, but in some cases also indicate high piston flow. We will show that still, 45 years after the peak of the bomb tritium, it is possible to assess accurately the parameters of age distributions by measuring the tail of the bomb tritium.

  5. Exploring similarities among many species distributions

    USGS Publications Warehouse

    Simmerman, Scott; Wang, Jingyuan; Osborne, James; Shook, Kimberly; Huang, Jian; Godsoe, William; Simons, Theodore R.

    2012-01-01

    Collecting species presence data and then building models to predict species distribution has been long practiced in the field of ecology for the purpose of improving our understanding of species relationships with each other and with the environment. Due to limitations of computing power as well as limited means of using modeling software on HPC facilities, past species distribution studies have been unable to fully explore diverse data sets. We build a system that can, for the first time to our knowledge, leverage HPC to support effective exploration of species similarities in distribution as well as their dependencies on common environmental conditions. Our system can also compute and reveal uncertainties in the modeling results enabling domain experts to make informed judgments about the data. Our work was motivated by and centered around data collection efforts within the Great Smoky Mountains National Park that date back to the 1940s. Our findings present new research opportunities in ecology and produce actionable field-work items for biodiversity management personnel to include in their planning of daily management activities.

  6. Modeled ground water age distributions

    USGS Publications Warehouse

    Woolfenden, Linda R.; Ginn, Timothy R.

    2009-01-01

    The age of ground water in any given sample is a distributed quantity representing distributed provenance (in space and time) of the water. Conventional analysis of tracers such as unstable isotopes or anthropogenic chemical species gives discrete or binary measures of the presence of water of a given age. Modeled ground water age distributions provide a continuous measure of contributions from different recharge sources to aquifers. A numerical solution of the ground water age equation of Ginn (1999) was tested both on a hypothetical simplified one-dimensional flow system and under real world conditions. Results from these simulations yield the first continuous distributions of ground water age using this model. Complete age distributions as a function of one and two space dimensions were obtained from both numerical experiments. Simulations in the test problem produced mean ages that were consistent with the expected value at the end of the model domain for all dispersivity values tested, although the mean ages for the two highest dispersivity values deviated slightly from the expected value. Mean ages in the dispersionless case also were consistent with the expected mean ages throughout the physical model domain. Simulations under real world conditions for three dispersivity values resulted in decreasing mean age with increasing dispersivity. This likely is a consequence of an edge effect. However, simulations for all three dispersivity values tested were mass balanced and stable demonstrating that the solution of the ground water age equation can provide estimates of water mass density distributions over age under real world conditions.

  7. The global age distribution of granitic pegmatites

    USGS Publications Warehouse

    McCauley, Andrew; Bradley, Dwight C.

    2014-01-01

    An updated global compilation of 377 new and previously published ages indicates that granitic pegmatites range in age from Mesoarchean to Neogene and have a semi-periodic age distribution. Undivided granitic pegmatites show twelve age maxima: 2913, 2687, 2501, 1853, 1379, 1174, 988, 525, 483, 391, 319, and 72 Ma. These peaks correspond broadly with various proxy records of supercontinent assembly, including the age distributions of granites, detrital zircon grains, and passive margins. Lithium-cesium-tantalum (LCT) pegmatites have a similar age distribution to the undivided granitic pegmatites, with maxima at 2638, 1800, 962, 529, 485, 371, 309, and 274 Ma. Lithium and Ta resources in LCT pegmatites are concentrated in the Archean and Phanerozoic. While there are some Li resources from the Proterozoic, the dominantly bimodal distribution of resources is particularly evident for Ta. This distribution is similar to that of orogenic gold deposits, and has been interpreted to reflect the preservation potential of the orogenic belts where these deposits are formed. Niobium-yttrium-fluorine (NYF) pegmatites show similar age distributions to LCT pegmatites, but with a strong maximum at ca. 1000 Ma.

  8. Age distribution of anginose mononucleosis.

    PubMed Central

    Spirer, Z; Holtzman, M; Melamed, I; Shalit, I

    1987-01-01

    The age distribution of anginose infectious mononucleosis in children was analysed retrospectively for the years 1966-85. During that period the disease became significantly more common in children of a young age and less common in older children. This shift could not be attributed either to socioeconomic conditions or to the diagnostic methods used. PMID:3619480

  9. Adult age similarities in free recall output order and strategies.

    PubMed

    Wright, R E

    1982-01-01

    Adult age differences on a variety of free recall measures were examined. Although primary memory capacity was found to be the same in young and old adults, there was a smaller recency effect in the older group. Recall of primacy items was also less for that group. However, the pattern of serial position effects was the same for the two age groups. Similarly, there was no age difference in the development of the strategy of recalling recency items early in the output sequence. Young adults showed the typical negative recency effect in final free recall, and old adults the absence of a positive recency effect. The results indicate that the lower level of recall of old, relative to young, adults cannot be attributed to a qualitative difference in the way the two age groups approach a free recall task.

  10. Similarity between humans and foams in aging dynamics

    NASA Astrophysics Data System (ADS)

    Weon, Byung Mook; Stewart, Peter S.

    2014-03-01

    Foams are cellular networks between two immiscible phases. Foams are initially unstable and finally evolve toward a state of lower energy through sequential coalescences of bubbles. In physics, foams are model systems for materials that minimize surface energy. We study coalescence dynamics of clean foams using numerical simulations with a network model. Initial clean foams consist of equally pressurized bubbles and a low fraction of liquid films without stabilizing agents. Aging of clean foams occurs with time as bubbles rapidly coalesce by film rupture and finally evolve toward a new quasi-equilibrium state. Here we find that foam aging is analogous to biological aging: the death rate of bubbles increases exponentially with time, which is similar to the Gompertz mortality law for biological populations. The coalescence evolution of foams is self-similar regardless of initial conditions. The population change of bubbles is well described by a Boltzmann sigmoidal function, indicating that the foam aging is a phase transition phenomenon. This result suggests that foams can be useful model systems for giving insights into biological aging. Suwon 440-746, South Korea.

  11. Distributed Efficient Similarity Search Mechanism in Wireless Sensor Networks

    PubMed Central

    Ahmed, Khandakar; Gregory, Mark A.

    2015-01-01

    The Wireless Sensor Network similarity search problem has received considerable research attention due to sensor hardware imprecision and environmental parameter variations. Most of the state-of-the-art distributed data centric storage (DCS) schemes lack optimization for similarity queries of events. In this paper, a DCS scheme with metric based similarity searching (DCSMSS) is proposed. DCSMSS takes motivation from vector distance index, called iDistance, in order to transform the issue of similarity searching into the problem of an interval search in one dimension. In addition, a sector based distance routing algorithm is used to efficiently route messages. Extensive simulation results reveal that DCSMSS is highly efficient and significantly outperforms previous approaches in processing similarity search queries. PMID:25751081

  12. Similarity of Symbol Frequency Distributions with Heavy Tails

    NASA Astrophysics Data System (ADS)

    Gerlach, Martin; Font-Clos, Francesc; Altmann, Eduardo G.

    2016-04-01

    Quantifying the similarity between symbolic sequences is a traditional problem in information theory which requires comparing the frequencies of symbols in different sequences. In numerous modern applications, ranging from DNA over music to texts, the distribution of symbol frequencies is characterized by heavy-tailed distributions (e.g., Zipf's law). The large number of low-frequency symbols in these distributions poses major difficulties to the estimation of the similarity between sequences; e.g., they hinder an accurate finite-size estimation of entropies. Here, we show analytically how the systematic (bias) and statistical (fluctuations) errors in these estimations depend on the sample size N and on the exponent γ of the heavy-tailed distribution. Our results are valid for the Shannon entropy (α =1 ), its corresponding similarity measures (e.g., the Jensen-Shanon divergence), and also for measures based on the generalized entropy of order α . For small α 's, including α =1 , the errors decay slower than the 1 /N decay observed in short-tailed distributions. For α larger than a critical value α*=1 +1 /γ ≤2 , the 1 /N decay is recovered. We show the practical significance of our results by quantifying the evolution of the English language over the last two centuries using a complete α spectrum of measures. We find that frequent words change more slowly than less frequent words and that α =2 provides the most robust measure to quantify language change.

  13. Distribution of similar earthquakes in aftershocks of inland earthquakes

    NASA Astrophysics Data System (ADS)

    Hayashi, M.; Hiramatsu, Y.; Aftershock Observations Of 2007 Noto Hanto, G.

    2010-12-01

    Frictional properties control the slip behavior on a fault surface such as seismic slip and aseismic slip. Asperity, as a seismic slip area, is characterized by a strong coupling in the interseismic period and large coseismic slip. On the other hand, steady slip or afterslip occurs in an aseismic slip area around the asperity. If an afterslip area includes small asperities, a repeating rupture of single asperity can generate similar earthquakes due to the stress accumulation caused by the afterslip. We here investigate a detail distribution of similar earthquakes in the aftershocks of the 2007 Noto Hanto earthquake (Mjma 6.9) and the 2000 Western Tottori earthquake (Mjma 7.3), inland large earthquakes in Japan. We use the data obtained by the group for the aftershock observations of the 2007 Noto Hanto Earthquake and by the group for the aftershock observations of the 2000 Western Tottori earthquake. First, we select pairs of aftershocks whose cross correlation coefficients in 10 s time window of band-pass filtered waveforms of 1~4 Hz are greater than 0.95 at more than 5 stations and divide those into groups by a link of the cross correlation coefficients. Second, we reexamine the arrival times of P and S waves and the maximum amplitude for earthquakes of each group and apply the double-difference method (Waldhouser and Ellsworth, 2000) to relocate them. As a result of the analysis, we find 24 groups of similar earthquakes in the aftershocks on the source fault of the 2007 Noto Hanto Earthquake and 86 groups of similar earthquakes in the aftershocks on the source fault of the 2000 Western Tottori Earthquake. Most of them are distributed around or outside the asperity of the main shock. Geodetic studies reported that postseismic deformation was detected for the both earthquakes (Sagiya et al., 2002; Hashimoto et al., 2008). The source area of similar earthquakes seems to correspond to the afterslip area. These features suggest that the similar earthquakes observed

  14. Spontaneous Object Recognition Memory in Aged Rats: Complexity versus Similarity

    ERIC Educational Resources Information Center

    Gamiz, Fernando; Gallo, Milagros

    2012-01-01

    Previous work on the effect of aging on spontaneous object recognition (SOR) memory tasks in rats has yielded controversial results. Although the results at long-retention intervals are consistent, conflicting results have been reported at shorter delays. We have assessed the potential relevance of the type of object used in the performance of…

  15. Age Similarities in Recognizing Threat From Faces and Diagnostic Cues

    PubMed Central

    Zebrowitz, Leslie A.; Franklin, Robert G.; McCormick, Cheryl M.; Carré, Justin M.

    2014-01-01

    Background. Previous research indicates that younger adults (YA) can identify men’s tendency to be aggressive based merely on their neutral expression faces. We compared older adults (OA) and YA accuracy and investigated contributing facial cues. Method. In Study 1, YA and OA rated the aggressiveness of young men depicted in facial photographs in a control, distraction, or accuracy motivation condition. In Study 2, YA and OA rated how angry, attractive, masculine, and babyfaced the men looked in addition to rating their aggressiveness. These measures plus measured facial width-to-height ratio (FWHR) were used to examine cues to aggressiveness. Results. Accuracy coefficients, calculated by correlating rated aggressiveness with the men’s previously measured actual aggressiveness, were significant and equal for OA and YA. Accuracy was not moderated by distraction or accuracy motivation, suggesting automatic processing. A greater FWHR, lower attractiveness, and higher masculinity independently influenced rated aggressiveness by both age groups and also were valid cues to actual aggressiveness. Discussion. Despite previous evidence for positivity biases in OA, they can be just as accurate as YA when it comes to discerning actual differences in the aggressiveness of young men. PMID:23743626

  16. Genetic similarity, breeding distribution range and sexual selection.

    PubMed

    Møller, A P; Garamszegi, L Z; Spottiswoode, C N

    2008-01-01

    Large populations with extensive breeding distributions may sustain greater genetic variability, thus producing a positive relationship between genetic variation and population size. Levels of genetic variability may also be affected by sexual selection, which could either reduce levels because a small fraction of males contribute to the following generation, or augment them by generating genetic variability through elevated rates of mutations. We investigated to what extent genetic variability, as estimated from band sharing coefficients for minisatellite markers, could be predicted by breeding distribution range, population size and intensity of sexual selection (as reflected by degree of polygyny and extra-pair paternity). Across a sample of 62 species of birds in the Western Palearctic, we found extensive interspecific variation in band sharing coefficients. High band sharing coefficients (implying low local genetic variability among individuals) were associated with restricted breeding distributions, a conclusion confirmed by analysis of statistically independent linear contrasts. Independently, species with large population sizes had small band sharing coefficients. Furthermore, bird species with a high richness of subspecies for their breeding distribution range had higher band sharing coefficients. Finally, bird species with high levels of polygyny and extra-pair paternity had small band sharing coefficients. These results suggest that breeding distribution range, population size and intensity of sexual selection are important predictors of levels of genetic variability in extant populations.

  17. Reduction of sound in ventilation and similar air distribution systems

    NASA Astrophysics Data System (ADS)

    1982-07-01

    This Data Item is available as part of the ESDU Sub-series on Fluid Mechanics Internal Flow. A means of estimating the attenuation of sound in lined plenum chambers and ducts, and through silencers of the types used in ventilation and air-conditioning systems is given. Data are provided in graphical or tabular form for the estimation of typical silencer insertion loss, airflow generated noise and pressure loss. Both rectangular splitter silencers and cylindrical silencers are considered. The data may be used in the initial design of a system or to investigate the appropriate remedial action for an installed air distribution system that is found to be too noisy. The location of silencers in the duct system is considered, and an example is given to illustrate the use of the data provided in the selection and sizing of a silencer for a particular application.

  18. A2E and lipofuscin distributions in macaque retinal pigment epithelium are similar to human.

    PubMed

    Pallitto, Patrick; Ablonczy, Zsolt; Jones, E Ellen; Drake, Richard R; Koutalos, Yiannis; Crouch, Rosalie K; Donello, John; Herrmann, Julia

    2015-10-01

    The accumulation of lipofuscin, an autofluorescent aging marker, in the retinal pigment epithelium (RPE) has been implicated in the development of age-related macular degeneration (AMD). Lipofuscin contains several visual cycle byproducts, most notably the bisretinoid N-retinylidene-N-retinylethanolamine (A2E). Previous studies with human donor eyes have shown a significant mismatch between lipofuscin autofluorescence (AF) and A2E distributions. The goal of the current project was to examine this relationship in a primate model with a retinal anatomy similar to that of humans. Ophthalmologically naive young (<10 years., N = 3) and old (>10 years., N = 4) Macaca fascicularis (macaque) eyes, were enucleated, dissected to yield RPE/choroid tissue, and flat-mounted on indium-tin-oxide-coated conductive slides. To compare the spatial distributions of lipofuscin and A2E, fluorescence and mass spectrometric imaging were carried out sequentially on the same samples. The distribution of lipofuscin fluorescence in the primate RPE reflected previously obtained human results, having the highest intensities in a perifoveal ring. Contrarily, A2E levels were consistently highest in the periphery, confirming a lack of correlation between the distributions of lipofuscin and A2E previously described in human donor eyes. We conclude that the mismatch between lipofuscin AF and A2E distributions is related to anatomical features specific to primates, such as the macula, and that this primate model has the potential to fill an important gap in current AMD research. PMID:26223373

  19. Distribution Matching with the Bhattacharyya Similarity: A Bound Optimization Framework.

    PubMed

    Ben Ayed, Ismail; Punithakumar, Kumaradevan; Shuo Li

    2015-09-01

    We present efficient graph cut algorithms for three problems: (1) finding a region in an image, so that the histogram (or distribution) of an image feature within the region most closely matches a given model; (2) co-segmentation of image pairs and (3) interactive image segmentation with a user-provided bounding box. Each algorithm seeks the optimum of a global cost function based on the Bhattacharyya measure, a convenient alternative to other matching measures such as the Kullback-Leibler divergence. Our functionals are not directly amenable to graph cut optimization as they contain non-linear functions of fractional terms, which make the ensuing optimization problems challenging. We first derive a family of parametric bounds of the Bhattacharyya measure by introducing an auxiliary labeling. Then, we show that these bounds are auxiliary functions of the Bhattacharyya measure, a result which allows us to solve each problem efficiently via graph cuts. We show that the proposed optimization procedures converge within very few graph cut iterations. Comprehensive and various experiments, including quantitative and comparative evaluations over two databases, demonstrate the advantages of the proposed algorithms over related works in regard to optimality, computational load, accuracy and flexibility.

  20. Linking age, survival, and transit time distributions

    NASA Astrophysics Data System (ADS)

    Calabrese, Salvatore; Porporato, Amilcare

    2015-10-01

    Although the concepts of age, survival, and transit time have been widely used in many fields, including population dynamics, chemical engineering, and hydrology, a comprehensive mathematical framework is still missing. Here we discuss several relationships among these quantities by starting from the evolution equation for the joint distribution of age and survival, from which the equations for age and survival time readily follow. It also becomes apparent how the statistical dependence between age and survival is directly related to either the age dependence of the loss function or the survival-time dependence of the input function. The solution of the joint distribution equation also allows us to obtain the relationships between the age at exit (or death) and the survival time at input (or birth), as well as to stress the symmetries of the various distributions under time reversal. The transit time is then obtained as a sum of the age and survival time, and its properties are discussed along with the general relationships between their mean values. The special case of steady state case is analyzed in detail. Some examples, inspired by hydrologic applications, are presented to illustrate the theory with the specific results. This article was corrected on 11 Nov 2015. See the end of the full text for details.

  1. Attraction to psychotherapy: influences of therapist status and therapist-patient age similarity.

    PubMed

    Lasky, R G; Salomone, P R

    1977-04-01

    Therapist-patient age similarity and therapist status were examined in relation to interpersonal attraction in the psychotherapy dyad. Psychiatric inpatients who comprised three age groupings were assigned randomly to one of four audiovisual treatments that depicted a dyadic psychotherapy situation (N = 60). For each treatment, therapist age and status were differentially presented on color slides with the same accompanying audiotape. Results indicated that age similarity was significantly (p less than .05) more relevant for the younger patients, whereas therapist status had greater significance for older patients. There were several significant interactions that concerned therapist-patient age similarity and therapist status effects on psychotherapeutic attraction. These results suggest that therapist-patient matching on age and/or therapist status should be considered carefully as a potential influence on therapeutic outcome. PMID:858795

  2. Age structure and income distribution policy.

    PubMed

    Von Weizsacker, R K

    1988-01-01

    The dependence of earnings on age is a firmly established empirical fact. A simple microeconomic model of educational choice, being consistent with this observation, is designed. The model lends itself readily to aggregation over individuals and age groups. Thus, relations can be set up between economic variables influencing the aggregate distribution of labor incomes and demographic variables determining the age structure of the population. The main results of the present study are: 1) overall earnings inequality is shown to be an increasing function of life expectancy and a decreasing function of fertility. 2) The effectiveness of redistributive policies is sensitive to the age composition. In particular, the inequality-reducing effect of a 1% income tax rise is shown to be smaller the older the population.

  3. Physiological correlates of division of labor among similarly aged honey bees.

    PubMed

    Huang, Z Y; Robinson, G E; Borst, D W

    1994-06-01

    Hormone analyses and exocrine gland measurements were made to probe for physiological correlates of division of labor among similarly aged adult worker honey bees (Apis mellifera L.). Middle-age bees (ca. 2 weeks old) performing different tasks showed significant differences in both juvenile hormone (JH) biosynthesis rates and hemolymph titers; guards and undertakers had high JH, and wax producers and food storers, low JH. Guards and undertakers had similar hormone levels to foragers, even though they were 10 days younger than foragers. No differences in JH were detected among young bees (1-week-old queen attendants and nurses) or older bees (3-4 week-old pollen foragers, non-pollen foragers, and soldiers). Hypopharyngeal gland size was inversely correlated with worker age and rate of JH biosynthesis, but soldiers had significantly larger hypopharyngeal glands than did foragers, despite their similar age and JH level. Results from soldiers indicate that exocrine gland development is not always linked with age-related behavior and endocrine development; they also support the recent claim that soldiers constitute a group of older bees that are distinct from foragers. Hormonal analyses indicate that the current model of JH's role in honey bee division of labor needs to be expanded because high levels of JH are associated with several other tasks besides foraging. JH may be involved in the regulation of division of labor among similarly aged workers in addition to its role in age-related division of labor.

  4. Self-similarity in the chemical evolution of galaxies and the delay-time distribution of SNe Ia

    NASA Astrophysics Data System (ADS)

    Walcher, C. J.; Yates, R. M.; Minchev, I.; Chiappini, C.; Bergemann, M.; Bruzual, G.; Charlot, S.; Coelho, P. R. T.; Gallazzi, A.; Martig, M.

    2016-10-01

    Recent improvements in the age dating of stellar populations and single stars allow us to study the ages and abundance of stars and galaxies with unprecedented accuracy. We here compare the relation between age and α-element abundances for stars in the solar neighborhood to that of local, early-type galaxies. We find these two relations to be very similar. Both fall into two regimes with a shallow slope for ages younger than ~9 Gyr and a steeper slope for ages older than that value. This quantitative similarity seems surprising because of the different types of galaxies and scales involved. For the sample of early-type galaxies we also show that the data are inconsistent with literature delay-time distributions of either single- or double-Gaussian shape. The data are consistent with a power-law delay-time distribution. We thus confirm that the delay-time distribution inferred for the Milky Way from chemical evolution arguments must also apply to massive early-type galaxies. We also offer a tentative explanation for the seeming universality of the age-[α/Fe] relation: it is the manifestation of averaging different stellar populations with varying chemical evolution histories.

  5. Self-similar optical pulses in competing cubic-quintic nonlinear media with distributed coefficients

    SciTech Connect

    Zhang Jiefang; Tian Qing; Wang Yueyue; Dai Chaoqing; Wu Lei

    2010-02-15

    We present a systematic analysis of the self-similar propagation of optical pulses within the framework of the generalized cubic-quintic nonlinear Schroedinger equation with distributed coefficients. By appropriately choosing the relations between the distributed coefficients, we not only retrieve the exact self-similar solitonic solutions, but also find both the approximate self-similar Gaussian-Hermite solutions and compact solutions. Our analytical and numerical considerations reveal that proper choices of the distributed coefficients could make the unstable solitons stable and could restrict the nonlinear interaction between the neighboring solitons.

  6. Age differences in same-different judgments as a function of multidimensional similarity.

    PubMed

    Scialfa, C T; Thomas, D M

    1994-07-01

    Age deficits in visual search often are attributed to difficulties in comparing display items to target representations. In the presence-absence search paradigm, however, these comparisons are frequently confounded with age differences in the latency and velocity of saccadic eye movements, reductions in the useful field of view (FOV), and retention of information concerning previously searched locations. To circumvent these shortcomings, 20 young and 20 older adults were compared in the speed of their same-different judgments of two perifoveal stimuli. The two stimuli were either identical or varied along one or more of the dimensions of size, shape, and color. In both age groups, RT for correct "different" judgments increased with stimulus similarity, an effect which was more pronounced in the elderly subjects. Results suggest that age differences in free search are due, in part, to an age-related decline in the speed of evaluating object congruence.

  7. Ageing and gonadectomy have similar effects on hypoglossal long-term facilitation in male Fischer rats

    PubMed Central

    Zabka, AG; Mitchell, GS; Behan, M

    2005-01-01

    Long-term facilitation (LTF), a form of serotonin-dependent respiratory plasticity induced by intermittent hypoxia, decreases with increasing age or following gonadectomy in male Sprague-Dawley (SD) rats. Ageing is accompanied by decreasing levels of testosterone, which in turn influences serotonergic function. In addition, LTF in young male rats differs among strains. Thus, we tested the hypothesis that LTF is similar in middle-aged and gonadectomized young male rats of an inbred rat strain commonly used in studies on ageing (F344) by comparison with SD rats. We further tested whether the magnitude of LTF correlates with circulating serum levels of testosterone and/or progesterone. Young and middle-aged intact and young gonadectomized (GDX) male Fischer 344 rats were anaesthetized, neuromuscularly blocked and ventilated. Integrated phrenic and hypoglossal (XII) nerve activities were measured before, during and 60 min following three 5-min episodes of isocapnic hypoxia. LTF was observed in phrenic motor output in young and middle-aged intact and young GDX rats. In contrast, XII LTF was observed only in young intact rats. In middle-aged and young GDX rats, XII LTF was significantly lower than in young intact rats (P < 0.05). Furthermore, XII LTF was positively correlated with the testosterone/progesterone ratio. These data show that serotonin-dependent plasticity in upper airway respiratory output is similar in F344 and SD rat strains. Furthermore, LTF is similarly impaired in middle-aged and gonadectomized male rats, suggesting that gonadal hormones play an important role in modulating the capacity for neuroplasticity in upper airway motor control. PMID:15613371

  8. Predicting human age using regional morphometry and inter-regional morphological similarity

    NASA Astrophysics Data System (ADS)

    Wang, Xun-Heng; Li, Lihua

    2016-03-01

    The goal of this study is predicting human age using neuro-metrics derived from structural MRI, as well as investigating the relationships between age and predictive neuro-metrics. To this end, a cohort of healthy subjects were recruited from 1000 Functional Connectomes Project. The ages of the participations were ranging from 7 to 83 (36.17+/-20.46). The structural MRI for each subject was preprocessed using FreeSurfer, resulting in regional cortical thickness, mean curvature, regional volume and regional surface area for 148 anatomical parcellations. The individual age was predicted from the combination of regional and inter-regional neuro-metrics. The prediction accuracy is r = 0.835, p < 0.00001, evaluated by Pearson correlation coefficient between predicted ages and actual ages. Moreover, the LASSO linear regression also found certain predictive features, most of which were inter-regional features. The turning-point of the developmental trajectories in human brain was around 40 years old based on regional cortical thickness. In conclusion, structural MRI could be potential biomarkers for the aging in human brain. The human age could be successfully predicted from the combination of regional morphometry and inter-regional morphological similarity. The inter-regional measures could be beneficial to investigating human brain connectome.

  9. STABILITY OF AGE-RELATED DEFICITS IN THE MNEMONIC SIMILARITY TASK ACROSS TASK VARIATIONS

    PubMed Central

    Stark, Shauna M.; Stevenson, Rebecca; Wu, Claudia; Rutledge, Samantha; Stark, Craig E. L.

    2015-01-01

    Several studies in our lab and others have demonstrated age-related declines in mnemonic discrimination during a recognition memory paradigm using repeated items, similar lures, and novel foils. In particular, older adults exhibit a shift in lure discriminability, identifying similar lures as old items at a greater rate than young adults. This shift likely reflects deficits in pattern separation processing as a result of underlying changes in the dentate gyrus of the hippocampus. Here, we explored whether alterations in the task design could rescue the age-related impairment or whether it was ubiquitous as one might expect if the neurobiological mechanisms were truly disturbed by typical aging. Despite overt instructions to study item details during encoding, we replicated the age-related deficit in mnemonic discrimination. We established reliable effects with short lists of stimuli and with repeated testing. Altering the task design from a study/test to a continuous recognition paradigm replicated the age-related shift in lure discrimination as well. Modifying the task to an old/new response (rather than old/similar/new) showed the same effect and a d′ analysis showed that lure items were more akin to target items in older adults. Finally, we varied the test instructions in order to promote gist or veridical responses in the old/new task. Even these overt, veridical test instructions did not ameliorate older adults’ lure discrimination problems. Together, these findings demonstrate the robust nature of this age-related deficit and support the hypothesis that typical aging results in neurobiological changes that underlie this impairment. PMID:26030427

  10. Cross-language distributions of high frequency and phonetically similar cognates.

    PubMed

    Schepens, Job; Dijkstra, Ton; Grootjen, Franc; van Heuven, Walter J B

    2013-01-01

    The coinciding form and meaning similarity of cognates, e.g. 'flamme' (French), 'Flamme' (German), 'vlam' (Dutch), meaning 'flame' in English, facilitates learning of additional languages. The cross-language frequency and similarity distributions of cognates vary according to evolutionary change and language contact. We compare frequency and orthographic (O), phonetic (P), and semantic similarity of cognates, automatically identified in semi-complete lexicons of six widely spoken languages. Comparisons of P and O similarity reveal inconsistent mappings in language pairs with deep orthographies. The frequency distributions show that cognate frequency is reduced in less closely related language pairs as compared to more closely related languages (e.g., French-English vs. German-English). These frequency and similarity patterns may support a better understanding of cognate processing in natural and experimental settings. The automatically identified cognates are available in the supplementary materials, including the frequency and similarity measurements.

  11. Similarly Strong Purifying Selection Acts on Human Disease Genes of All Evolutionary Ages

    PubMed Central

    Cai, James J.; Borenstein, Elhanan; Chen, Rong

    2009-01-01

    A number of studies have showed that recently created genes differ from the genes created in deep evolutionary past in many aspects. Here, we determined the age of emergence and propensity for gene loss (PGL) of all human protein–coding genes and compared disease genes with non-disease genes in terms of their evolutionary rate, strength of purifying selection, mRNA expression, and genetic redundancy. The older and the less prone to loss, non-disease genes have been evolving 1.5- to 3-fold slower between humans and chimps than young non-disease genes, whereas Mendelian disease genes have been evolving very slowly regardless of their ages and PGL. Complex disease genes showed an intermediate pattern. Disease genes also have higher mRNA expression heterogeneity across multiple tissues than non-disease genes regardless of age and PGL. Young and middle-aged disease genes have fewer similar paralogs as non-disease genes of the same age. We reasoned that genes were more likely to be involved in human disease if they were under a strong functional constraint, expressed heterogeneously across tissues, and lacked genetic redundancy. Young human genes that have been evolving under strong constraint between humans and chimps might also be enriched for genes that encode important primate or even human-specific functions. PMID:20333184

  12. Regrowth after skeletal muscle atrophy is impaired in aged rats, despite similar responses in signaling pathways

    PubMed Central

    White, Jena R.; Confides, Amy L.; Moore-Reed, Stephanie; Hoch, Johanna M.; Dupont-Versteegden, Esther E.

    2015-01-01

    Skeletal muscle regrowth after atrophy is impaired in the aged and in this study we hypothesized that this can be explained by a blunted response of signaling pathways and cellular processes during reloading after hind limb suspension in muscles from old rats. Male Brown Norway Fisher 344 rats at 6 (young) and 32 (old) months of age were subjected to normal ambulatory conditions (amb), hind limb suspension for 14 days (HS), and HS followed by reloading through normal ambulation for 14 days (RE); soleus muscles were used for analysis of intracellular signaling pathways and cellular processes. Soleus muscle regrowth was blunted in old compared to young rats which coincided with a recovery of serum IGF-1 and IGFBP-3 levels in young but not old. However, the response to reloading for p-Akt, p-p70s6k and p-GSK3β protein abundance was similar between muscles from young and old rats, even though main effects for age indicate an increase in activation of this protein synthesis pathway in the aged. Similarly, MAFbx mRNA levels in soleus muscle from old rats recovered to the same extent as in the young, while Murf-1 was unchanged. mRNA abundance of autophagy markers Atg5 and Atg7 showed an identical response in muscle from old compared to young rats, but beclin did not. Autophagic flux was not changed at either age at the measured time point. Apoptosis was elevated in soleus muscle from old rats particularly with HS, but recovered in HSRE and these changes were not associated with differences in caspase-3, -8 or-9 activity in any group. Protein abundance of apoptosis repressor with caspase-recruitment domain (ARC), cytosolic EndoG, as well as cytosolic and nuclear apoptosis inducing factor (AIF) were lower in muscle from old rats, and there was no age-related difference in the response to atrophy or regrowth. Soleus muscles from old rats had a higher number of ED2 positive macrophages in all groups and these decreased with HS, but recovered in HSRE in the old, while no

  13. Aged Boreal Biomass Burning Size Distributions from Bortas 2011

    NASA Astrophysics Data System (ADS)

    Pierce, J. R.; Sakamoto, K.; Allan, J. D.; Coe, H.; Taylor, J.; Duck, T.

    2014-12-01

    Biomass-burning aerosols contribute to aerosol radiative forcing on the climate system. The magnitude of this effect is partially determined by aerosol size distributions, which are strong functions of source fire characteristics (e.g. fuel type, MCE) and in-plume microphysical processing. The uncertainties in biomass-burning emission number size-distributions in climate model inventories lead to uncertainties in the CCN concentrations and forcing estimates derived from these models. The BORTAS-B measurement campaign was designed to sample boreal biomass-burning outflow over Eastern Canada in the summer of 2011. Using these BORTAS-B data, we implement plume criteria to isolate the characteristic size-distribution of aged biomass-burning emissions (aged ~ 1.5 - 2 days) from boreal wildfires in Northwestern Ontario. The composite median size-distribution yields a single dominant accumulation mode with Dpm = 232 nm, σ = 1.7, which are comparable to literature values of other aged plumes of a similar type. The organic aerosol enhancement ratios (ΔOA/ΔCO) along the path of Flight b622 show values of 0.08-0.18 μg m-3 ppbv-1 with no significant trend with distance from the source. This lack of enhancement ratio increase/decrease with distance suggests no detectable net OA production/evaporation within the aged plume over the sampling period. A Lagrangian microphysical model was used to determine an estimate of the freshly emitted size distribution and flux corresponding to the BORTAS-B aged size-distributions. The model was restricted to coagulation and dilution processes only based on the insignificant net OA production/evaporation derived from the ΔOA/ΔCO enhancement ratios. Depending on the, we estimate that the fresh-plume median diameter was in the range of 59-94 nm with modal widths in the range of 1.7-2.8. Thus, the size of the freshly emitted particles is somewhat unconstrained due to the uncertainties in the plume dilution rates.

  14. Aged boreal biomass burning aerosol size distributions from BORTAS 2011

    NASA Astrophysics Data System (ADS)

    Sakamoto, K. M.; Allan, J. D.; Coe, H.; Taylor, J. W.; Duck, T. J.; Pierce, J. R.

    2014-09-01

    Biomass-burning aerosols contribute to aerosol radiative forcing on the climate system. The magnitude of this effect is partially determined by aerosol size distributions, which are functions of source fire characteristics (e.g. fuel type, MCE) and in-plume microphysical processing. The uncertainties in biomass-burning emission number size-distributions in climate model inventories lead to uncertainties in the CCN concentrations and forcing estimates derived from these models. The BORTAS-B measurement campaign was designed to sample boreal biomass-burning outflow over Eastern Canada in the summer of 2011. Using these BORTAS-B data, we implement plume criteria to isolate the characteristic size-distribution of aged biomass-burning emissions (aged ∼1-2 days) from boreal wildfires in Northwestern Ontario. The composite median size-distribution yields a single dominant accumulation mode with Dpm = 230 nm (number-median diameter), σ = 1.7, which are comparable to literature values of other aged plumes of a similar type. The organic aerosol enhancement ratios (ΔOA / ΔCO) along the path of Flight b622 show values of 0.05-0.18 μg m-3 ppbv-1 with no significant trend with distance from the source. This lack of enhancement ratio increase/decrease with distance suggests no detectable net OA production/evaporation within the aged plume over the sampling period. A Lagrangian microphysical model was used to determine an estimate of the freshly emitted size distribution corresponding to the BORTAS-B aged size-distributions. The model was restricted to coagulation and dilution processes based on the insignificant net OA production/evaporation derived from the ΔOA / ΔCO enhancement ratios. We estimate that the fresh-plume median diameter was in the range of 59-94 nm with modal widths in the range of 1.7-2.8 (the ranges are due to uncertainty in the entrainment rate). Thus, the size of the freshly emitted particles is relatively unconstrained due to the uncertainties in

  15. Coping with Distribution Change in the Same Domain Using Similarity-Based Instance Weighting

    NASA Astrophysics Data System (ADS)

    Son, Jeong-Woo; Song, Hyun-Je; Park, Seong-Bae; Park, Se-Young

    Lexicons are considered as the most crucial features in natural language processing (NLP), and thus often used in machine learning algorithms applied to NLP tasks. However, due to the diversity of lexical space, the machine learning algorithms with lexical features suffer from the difference between distributions of training and test data. In order to overcome the distribution change, this paper proposes support vector machines with example-wise weights. The training distribution coincides with the test distribution by weighting training examples according to their similarity to all test data. The experimental results on text chunking show that the distribution change between training and test data is actually recognized and the proposed method which considers this change in its training phase outperforms ordinary support vector machines.

  16. Similar degrees of obesity induced by diet or aging cause strikingly different immunologic and metabolic outcomes.

    PubMed

    Krishna, Kanthi B; Stefanovic-Racic, Maja; Dedousis, Nikolaos; Sipula, Ian; O'Doherty, Robert M

    2016-03-01

    In obesity, adipose tissue (AT) and liver are infiltrated with Th-1 polarized immune cells, which are proposed to play an important role in the pathogenesis of the metabolic abnormalities of obesity. Aging is also associated with increased adiposity, but the effects of this increase on inflammation and associated metabolic dysfunction are poorly understood. To address this issue, we assessed insulin resistance (IR) andATand liver immunophenotype in aged, lean (AL) and aged, obese (AO) mice, all of whom were maintained on a standard chow diet (11% fat diet) throughout their lives. For comparison, these variables were also assessed in young, lean (YL) and young diet-induced obese mice (41% fat diet,YO). Despite similar body weight and fat accumulation,YOmice were substantially moreIRand had greater liver steatosis compared toAOmice.YOalso had elevated infiltration of macrophages/dendritic cells inATand liver, but these increases were absent inAO Furthermore, liver immune cells ofYOwere more Th-1 polarized thenAO Notably, aging was associated with accumulation of T cells, but this occurred independent of obesity. Together, the data suggest that reduced inflammation inAOunderlies the improved insulin sensitivity and lowered steatosis compared toYO.

  17. Distributional Phonetic Learning at 10 Months of Age

    ERIC Educational Resources Information Center

    Yoshida, Katherine A.; Pons, Ferran; Maye, Jessica; Werker, Janet F.

    2010-01-01

    Infant phonetic perception reorganizes in accordance with the native language by 10 months of age. One mechanism that may underlie this perceptual change is distributional learning, a statistical analysis of the distributional frequency of speech sounds. Previous distributional learning studies have tested infants of 6-8 months, an age at which…

  18. Collaborative distribution of remote sensing data based on user profile similarity

    NASA Astrophysics Data System (ADS)

    Li, Xinguang; Liu, Yang; Li, Yunhua; Wang, Yuhua

    2015-12-01

    With the rapid development of earth observation technology and the rapid increase of remote sensors, the amount of remote sensing data rapidly expands, which leads to increasingly outstanding contradiction of "more and less" remote sensing data. According to the user's preference characteristics, intelligent distribution of remote sensing data is an effective solution to the problem. The user profile model is the basis of intelligent distribution of remote sensing data. This paper intends to (1) establish the user profile model which describes the user's preference characteristics of remote sensing data; (2) develop similarity measure methods of user profile models, according to which similarities of user preference characteristics can be calculated; (3) put forward prediction methods of the user's ratings of remote sensing data, based on which remote sensing data can be collaboratively distributed.

  19. Effects of aluminium sulphate in the mouse liver: similarities to the aging process.

    PubMed

    Stacchiotti, Alessandra; Lavazza, Antonio; Ferroni, Matteo; Sberveglieri, Giorgio; Bianchi, Rossella; Rezzani, Rita; Rodella, Luigi Fabrizio

    2008-04-01

    Aluminium (Al) is a ubiquitous metal that is potentially toxic to the brain. Its effects on other fundamental organs are not completely understood. This morphological in vivo study sought to compare sublethal hepatotoxic changes and Al deposition in adult mice that orally ingested Al sulphate daily for 10 months, in age matched control mice that drank tap water and in senescent mice (24 months old). Livers were examined for collagen deposition using Sirius red and Masson, for iron accumulation using Perls' stain. Light, electron microscopy and morphometry were used to assess fibrosis and vascular changes. Scanning transmission electron microscopy and EDX microanalysis were used to detect in situ elemental Al. Iron deposition, transferrin receptor expression were significantly altered following Al exposure and in the aged liver but were unaffected in age matched control mice. In Al treated mice as in senescent mice, endothelial thickness was increased and porosity was decreased like perisinusoidal actin. Furthermore, Al stimulated the deposition of collagen and laminin, mainly in acinar zones 1 and 3. Pseudocapillarization and periportal laminin in senescent mice were similar to Al treated adult liver. In conclusion, prolonged Al sulphate intake accelerates features of senescence in the adult mice liver.

  20. Using landscape organization and functional similarity to reduce redundancy in distributed hydrological modeling

    NASA Astrophysics Data System (ADS)

    Zehe, Erwin; Ehret, Uwe; Scherer, Ulrike; Kasparek, Axel

    2014-05-01

    The landscapes we see are, to a large degree, not random combinations of their constituents. Rather we witness organization in the form of recurring, typical combinations of morphology, soils, vegetation, hydro-climate etc. A typical example in cool-moist hydro-climate at mid-altitudes would be a coniferous forested hill slope on shallow hydrophobic soils. If we thus hypothesize that landscape is composed of non-unique, recurring entities, and if we further hypothesize that any two systems that share a similar structure, are in a similar initial state and are exposed to similar forcing will produce similar integral responses based on similar internal dynamics, then many of the computations in distributed hydrological models will be redundant. For instance, if we knew the internal dynamics and response of a hill slope to a rainstorm, we should be able to predict the response of a neighboring hill slope without explicitly computing its dynamics by transferring the results of its neighbor. If this is true, then exploiting this redundancy has the potential to greatly reduce computational efforts in distributed modeling, while still considering structure and dynamics in high spatial and temporal resolution (unlike lumped approaches). The challenge then lies in the questions: - What degree of similarity is sufficient to dynamically group landscape entities of similar structure, state and forcing? - What are rules to decide on the temporal extend of such groups? - How to select a representative group member to compute dynamics and how to assign the resulting state changes and responses back to each group member? In this work, we introduce the concept of 'representative computation' and present results from a first application in the 3.5 km² Weiherbach catchment in Germany. The Weiherbach is situated in a hilly, intensively cultivated loess region composed of typical convex-concave shaped slopes and erosion catenas. The catchment was subdivided into 169 hill slopes and

  1. Age distribution among NASA scientists and engineers

    NASA Technical Reports Server (NTRS)

    Ciancone, Michael L.

    1989-01-01

    The loss of technical expertise through attrition in NASA and the aerospace industry is discussed. This report documents historical age-related information for scientific and engineering personnel in general and the NASA Lewis Research Center in particular, for 1968 through 1987. Recommendations are made to promote discussion and to establish the groundwork for action.

  2. PATTERNS OF ROOT GROWTH, TURNOVER, AND DISTRIBUTION IN DIFFERENT AGED PONDEROSA PINE STANDS

    EPA Science Inventory

    The objectives of this study are to examine the spatial distribution of roots in relation to canopy size and tree distribution, and to determine if rates of fine root production and turnover are similar in the different aged stands. During the fall of 1998, 54 clear plexiglass t...

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

    PubMed Central

    Zhao, Wei; Wang, Han

    2016-01-01

    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. PMID:27367691

  4. Size distribution of dust grains: A problem of self-similarity

    NASA Technical Reports Server (NTRS)

    Henning, TH.; Dorschner, J.; Guertler, J.

    1989-01-01

    Distribution functions describing the results of natural processes frequently show the shape of power laws, e.g., mass functions of stars and molecular clouds, velocity spectrum of turbulence, size distributions of asteroids, micrometeorites and also interstellar dust grains. It is an open question whether this behavior is a result simply coming about by the chosen mathematical representation of the observational data or reflects a deep-seated principle of nature. The authors suppose the latter being the case. Using a dust model consisting of silicate and graphite grains Mathis et al. (1977) showed that the interstellar extinction curve can be represented by taking a grain radii distribution of power law type n(a) varies as a(exp -p) with 3.3 less than or equal to p less than or equal to 3.6 (example 1) as a basis. A different approach to understanding power laws like that in example 1 becomes possible by the theory of self-similar processes (scale invariance). The beta model of turbulence (Frisch et al., 1978) leads in an elementary way to the concept of the self-similarity dimension D, a special case of Mandelbrot's (1977) fractal dimension. In the frame of this beta model, it is supposed that on each stage of a cascade the system decays to N clumps and that only the portion beta N remains active further on. An important feature of this model is that the active eddies become less and less space-filling. In the following, the authors assume that grain-grain collisions are such a scale-invarient process and that the remaining grains are the inactive (frozen) clumps of the cascade. In this way, a size distribution n(a) da varies as a(exp -(D+1))da (example 2) results. It seems to be highly probable that the power law character of the size distribution of interstellar dust grains is the result of a self-similarity process. We can, however, not exclude that the process leading to the interstellar grain size distribution is not fragmentation at all. It could be, e

  5. Selecting valuable information to remember: age-related differences and similarities in self-regulated learning.

    PubMed

    Castel, Alan D; Murayama, Kou; Friedman, Michael C; McGillivray, Shannon; Link, Ian

    2013-03-01

    It is often necessary to selectively attend to important information, at the expense of less important information, especially if you know you cannot remember large amounts of information. The present study examined how younger and older adults select valuable information to study, when given unrestricted choices about how to allocate study time. Participants were shown a display of point values ranging from 1-30. Participants could choose which values to study, and the associated word was then shown. Study time, and the choice to restudy words, was under the participant's control during the 2-minute study session. Overall, both age groups selected high value words to study and studied these more than the lower value words. However, older adults allocated a disproportionately greater amount of study time to the higher-value words, and age-differences in recall were reduced or eliminated for the highest value words. In addition, older adults capitalized on recency effects in a strategic manner, by studying high-value items often but also immediately before the test. A multilevel mediation analysis indicated that participants strategically remembered items with higher point value, and older adults showed similar or even stronger strategic process that may help to compensate for poorer memory. These results demonstrate efficient (and different) metacognitive control operations in younger and older adults, which can allow for strategic regulation of study choices and allocation of study time when remembering important information. The findings are interpreted in terms of life span models of agenda-based regulation and discussed in terms of practical applications.

  6. Self-Similar Structure and Experimental Signatures of Suprathermal Ion Distribution in Inertial Confinement Fusion Implosions.

    PubMed

    Kagan, Grigory; Svyatskiy, D; Rinderknecht, H G; Rosenberg, M J; Zylstra, A B; Huang, C-K; McDevitt, C J

    2015-09-01

    The distribution function of suprathermal ions is found to be self-similar under conditions relevant to inertial confinement fusion hot spots. By utilizing this feature, interference between the hydrodynamic instabilities and kinetic effects is for the first time assessed quantitatively to find that the instabilities substantially aggravate the fusion reactivity reduction. The ion tail depletion is also shown to lower the experimentally inferred ion temperature, a novel kinetic effect that may explain the discrepancy between the exploding pusher experiments and rad-hydro simulations and contribute to the observation that temperature inferred from DD reaction products is lower than from DT at the National Ignition Facility. PMID:26382682

  7. Self-similar structure and experimental signatures of suprathermal ion distribution in inertial confinement fusion implosions

    SciTech Connect

    Kagan, Grigory; Svyatskiy, D.; Rinderknecht, H. G.; Rosenberg, M. J.; Zylstra, A. B.; Huang, C. -K.; McDevitt, C. J.

    2015-09-03

    The distribution function of suprathermal ions is found to be self-similar under conditions relevant to inertial confinement fusion hot spots. By utilizing this feature, interference between the hydrodynamic instabilities and kinetic effects is for the first time assessed quantitatively to find that the instabilities substantially aggravate the fusion reactivity reduction. Thus, the ion tail depletion is also shown to lower the experimentally inferred ion temperature, a novel kinetic effect that may explain the discrepancy between the exploding pusher experiments and rad-hydro simulations and contribute to the observation that temperature inferred from DD reaction products is lower than from DT at the National Ignition Facility.

  8. Spatio-Temporal Distribution Characteristics and Trajectory Similarity Analysis of Tuberculosis in Beijing, China.

    PubMed

    Li, Lan; Xi, Yuliang; Ren, Fu

    2016-03-01

    Tuberculosis (TB) is an infectious disease with one of the highest reported incidences in China. The detection of the spatio-temporal distribution characteristics of TB is indicative of its prevention and control conditions. Trajectory similarity analysis detects variations and loopholes in prevention and provides urban public health officials and related decision makers more information for the allocation of public health resources and the formulation of prioritized health-related policies. This study analysed the spatio-temporal distribution characteristics of TB from 2009 to 2014 by utilizing spatial statistics, spatial autocorrelation analysis, and space-time scan statistics. Spatial statistics measured the TB incidence rate (TB patients per 100,000 residents) at the district level to determine its spatio-temporal distribution and to identify characteristics of change. Spatial autocorrelation analysis was used to detect global and local spatial autocorrelations across the study area. Purely spatial, purely temporal and space-time scan statistics were used to identify purely spatial, purely temporal and spatio-temporal clusters of TB at the district level. The other objective of this study was to compare the trajectory similarities between the incidence rates of TB and new smear-positive (NSP) TB patients in the resident population (NSPRP)/new smear-positive TB patients in the TB patient population (NSPTBP)/retreated smear-positive (RSP) TB patients in the resident population (RSPRP)/retreated smear-positive TB patients in the TB patient population (RSPTBP) to detect variations and loopholes in TB prevention and control among the districts in Beijing. The incidence rates in Beijing exhibited a gradual decrease from 2009 to 2014. Although global spatial autocorrelation was not detected overall across all of the districts of Beijing, individual districts did show evidence of local spatial autocorrelation: Chaoyang and Daxing were Low-Low districts over the six

  9. Spatio-Temporal Distribution Characteristics and Trajectory Similarity Analysis of Tuberculosis in Beijing, China

    PubMed Central

    Li, Lan; Xi, Yuliang; Ren, Fu

    2016-01-01

    Tuberculosis (TB) is an infectious disease with one of the highest reported incidences in China. The detection of the spatio-temporal distribution characteristics of TB is indicative of its prevention and control conditions. Trajectory similarity analysis detects variations and loopholes in prevention and provides urban public health officials and related decision makers more information for the allocation of public health resources and the formulation of prioritized health-related policies. This study analysed the spatio-temporal distribution characteristics of TB from 2009 to 2014 by utilizing spatial statistics, spatial autocorrelation analysis, and space-time scan statistics. Spatial statistics measured the TB incidence rate (TB patients per 100,000 residents) at the district level to determine its spatio-temporal distribution and to identify characteristics of change. Spatial autocorrelation analysis was used to detect global and local spatial autocorrelations across the study area. Purely spatial, purely temporal and space-time scan statistics were used to identify purely spatial, purely temporal and spatio-temporal clusters of TB at the district level. The other objective of this study was to compare the trajectory similarities between the incidence rates of TB and new smear-positive (NSP) TB patients in the resident population (NSPRP)/new smear-positive TB patients in the TB patient population (NSPTBP)/retreated smear-positive (RSP) TB patients in the resident population (RSPRP)/retreated smear-positive TB patients in the TB patient population (RSPTBP) to detect variations and loopholes in TB prevention and control among the districts in Beijing. The incidence rates in Beijing exhibited a gradual decrease from 2009 to 2014. Although global spatial autocorrelation was not detected overall across all of the districts of Beijing, individual districts did show evidence of local spatial autocorrelation: Chaoyang and Daxing were Low-Low districts over the six

  10. Spatio-Temporal Distribution Characteristics and Trajectory Similarity Analysis of Tuberculosis in Beijing, China.

    PubMed

    Li, Lan; Xi, Yuliang; Ren, Fu

    2016-03-07

    Tuberculosis (TB) is an infectious disease with one of the highest reported incidences in China. The detection of the spatio-temporal distribution characteristics of TB is indicative of its prevention and control conditions. Trajectory similarity analysis detects variations and loopholes in prevention and provides urban public health officials and related decision makers more information for the allocation of public health resources and the formulation of prioritized health-related policies. This study analysed the spatio-temporal distribution characteristics of TB from 2009 to 2014 by utilizing spatial statistics, spatial autocorrelation analysis, and space-time scan statistics. Spatial statistics measured the TB incidence rate (TB patients per 100,000 residents) at the district level to determine its spatio-temporal distribution and to identify characteristics of change. Spatial autocorrelation analysis was used to detect global and local spatial autocorrelations across the study area. Purely spatial, purely temporal and space-time scan statistics were used to identify purely spatial, purely temporal and spatio-temporal clusters of TB at the district level. The other objective of this study was to compare the trajectory similarities between the incidence rates of TB and new smear-positive (NSP) TB patients in the resident population (NSPRP)/new smear-positive TB patients in the TB patient population (NSPTBP)/retreated smear-positive (RSP) TB patients in the resident population (RSPRP)/retreated smear-positive TB patients in the TB patient population (RSPTBP) to detect variations and loopholes in TB prevention and control among the districts in Beijing. The incidence rates in Beijing exhibited a gradual decrease from 2009 to 2014. Although global spatial autocorrelation was not detected overall across all of the districts of Beijing, individual districts did show evidence of local spatial autocorrelation: Chaoyang and Daxing were Low-Low districts over the six

  11. Estimating Model Parameter Uncertainty Using A Distribution Oriented Approach and a Similarity Measure

    NASA Astrophysics Data System (ADS)

    Tcherednichenko, I. A.; Bastidas, L. A.; Lansey, K.

    2004-12-01

    We use two very recently introduced in hydrology measures of performance: the Distributions Oriented (DO) approach and a set theory-based similarity metric - the Hausdorff Norm (HN) to evaluate the performance of two extensively used distributed rainfall-runoff models: Topmodel and PRMS. The distribution oriented approach considers the bivariate distribution of model outputs and observations and the corresponding marginal distributions. The Hausdorff norm allows for the inclusion, within the same framework or measure, both the spatial and temporal scales as a single multi-dimensional array. The performance evaluation is carried out over different time and spatial scales. The models are run over two nested catchments located in different climatic environments - one relatively wet, the Blue River in Oklahoma, and other semi-arid - the Sycamore Creek in Arizona. The levels and quality of input information are very dissimilar. To drive the models radar precipitation is used for the Blue River while the products generated at the University of Washington and gage measurements are used for Sycamore Creek. Both catchments have nested gages and the models are run to simulate 10 years of daily runoff at those points with different levels of discretization/resolution. Both measures: the DO and the HN, are used for parameter estimation using the multiple objective framework developed at the University of Arizona -that allows for the inclusion of trade-off uncertainties of the objective functions, and are compared against each other and against traditional scalar measures of performance as Nash Sutcliffe efficiency, bias, and general duration curves. In the Sycamore Creek a PRMS parameterization of the channel transmission losses is also considered for evaluation because of the important role played by those losses in the shape of the hydrographs.

  12. Distributed Similarity based Clustering and Compressed Forwarding for wireless sensor networks.

    PubMed

    Arunraja, Muruganantham; Malathi, Veluchamy; Sakthivel, Erulappan

    2015-11-01

    Wireless sensor networks are engaged in various data gathering applications. The major bottleneck in wireless data gathering systems is the finite energy of sensor nodes. By conserving the on board energy, the life span of wireless sensor network can be well extended. Data communication being the dominant energy consuming activity of wireless sensor network, data reduction can serve better in conserving the nodal energy. Spatial and temporal correlation among the sensor data is exploited to reduce the data communications. Data similar cluster formation is an effective way to exploit spatial correlation among the neighboring sensors. By sending only a subset of data and estimate the rest using this subset is the contemporary way of exploiting temporal correlation. In Distributed Similarity based Clustering and Compressed Forwarding for wireless sensor networks, we construct data similar iso-clusters with minimal communication overhead. The intra-cluster communication is reduced using adaptive-normalized least mean squares based dual prediction framework. The cluster head reduces the inter-cluster data payload using a lossless compressive forwarding technique. The proposed work achieves significant data reduction in both the intra-cluster and the inter-cluster communications, with the optimal data accuracy of collected data.

  13. Growth of river delta networks: Thresholds, periodicity, aging and self similarity (Invited)

    NASA Astrophysics Data System (ADS)

    Jerolmack, D. J.; Reitz, M. D.

    2010-12-01

    The surfaces of river deltas and alluvial fans (collectively fans) are often dissected by a small number of channels radiating from the fan apex. These dispersive, depositional systems do not exhibit the fractal scaling typical of erosional drainage networks. On long timescales, fan channels migrate via avulsion - the process of channel bed deposition and abandonment. What governs the selection of new flow paths, or the ultimate number of active channels, is poorly understood. Here we present results of an experimental fan that allow us to examine the growth of a depositional channel network. Flow over the fan collapses into a single channel whose dimensions adjust to threshold transport conditions for the imposed sediment load. This channelization causes localized shoreline growth, which diminishes transport capacity of the channel until the slope drops below the threshold value. This leads to deposition within the channel and widespread flooding; avulsion is completed when a new channel path is selected. This cycle is remarkably periodic, and dynamics suggest that fan slope oscillates between two thresholds - entrainment and distrainment - analogous to static and dynamic angles of repose in grain flows. Selection of a new flow path is inherently stochastic, but previously abandoned channels act as significant attractors for the flow. In the early stages of fan growth, new channels are likely to be created. Once a critical density of flow paths has been established, however, the flow oscillates among the same 3-5 channels indefinitely. These dynamics are similar to the aging phenomenon observed in the growth of fractures in brittle materials under stress. We demonstrate that a directed random walk model with memory quantitatively reproduces these dynamics and limiting behavior, and is consistent with natural fans. Because our experimental fan is built by the recurring avulsion sequence, its shoreline shape is a series of lobes that indicate persistent upstream

  14. Phytoplankton distribution in three thermally different but edaphically similar reactor cooling reservoirs

    SciTech Connect

    Wilde, E W

    1982-01-01

    Phytoplankton community structure and the physicochemical characteristics of three reactor cooling reservoirs in close proximity and of similar age and bottom type were studied during 1978. The three reservoirs differed in thermal alteration resulting from reactor cooling water as follows: (1) considerable heating with lake-wide temperatures >30/sup 0/C, even in winter; (2) a maximal 5/sup 0/C increase occurring in only one of three major arms of the reservoir; and (3) no thermal effluent received during the study period. Considerable spatial and temporal differences in water quality and phytoplankton community structure were observed; however, water temperature independent of other environmental factors (e.g., light and nutrients) was found to be a relatively unimportant variable for explaining phytoplankton periodicity.

  15. Are lorazepam-induced deficits in attention similar to those resulting from aging?

    PubMed

    Fluck, E; Fernandes, C; File, S E

    2001-04-01

    The purpose of this experiment was to compare, in three tasks of attention, the impairment caused by lorazepam (1 and 2.5 mg) administered to young volunteers with the impairment that results from aging. Performance on digit cancellation (DC), digit-symbol substitution (DSS), and Paced Auditory Serial Addition Task (PASAT) was significantly impaired by lorazepam (2.5 mg) and was significantly worse in the middle-aged group (mean +/- SEM, aged 58.9+/-0.8 years) compared with the younger, IQ-matched group (20.7+/-0.2 years). However, there were interesting differences in the extent of impairments among the three tests. In the DC test, lorazepam (2.5 mg) produced a significantly greater impairment than was seen in either the middle-aged men or middle-aged women. However, in the DSS test, the middle-aged women were significantly more impaired than either the middle-aged men or the young volunteers tested after lorazepam (2.5 mg). In the PASAT, both the lorazepam (2.5 mg) group and the middle-aged women were more impaired than the middle-aged men. These results raise the important possibility of gender differences in age-related decline of attentional processes.

  16. Self-similar structure and experimental signatures of suprathermal ion distribution in inertial confinement fusion implosions

    DOE PAGES

    Kagan, Grigory; Svyatskiy, D.; Rinderknecht, H. G.; Rosenberg, M. J.; Zylstra, A. B.; Huang, C. -K.; McDevitt, C. J.

    2015-09-03

    The distribution function of suprathermal ions is found to be self-similar under conditions relevant to inertial confinement fusion hot spots. By utilizing this feature, interference between the hydrodynamic instabilities and kinetic effects is for the first time assessed quantitatively to find that the instabilities substantially aggravate the fusion reactivity reduction. Thus, the ion tail depletion is also shown to lower the experimentally inferred ion temperature, a novel kinetic effect that may explain the discrepancy between the exploding pusher experiments and rad-hydro simulations and contribute to the observation that temperature inferred from DD reaction products is lower than from DT atmore » the National Ignition Facility.« less

  17. Early Visual Tagging: Effects of Target-Distractor Similarity and Old Age on Search, Subitization, and Counting

    ERIC Educational Resources Information Center

    Watson, Derrick G.; Maylor, Elizabeth A.; Allen, Gareth E. J.; Bruce, Lucy A. M.

    2007-01-01

    Three experiments examined the effects of target-distractor (T-D) similarity and old age on the efficiency of searching for single targets and enumerating multiple targets. Experiment 1 showed that increasing T-D similarity selectively reduced the efficiency of enumerating small (less than 4) numerosities (subitizing) but had little effect on…

  18. The similarity structure of distributed neural responses reveals the multiple representations of letters

    PubMed Central

    Rothlein, David; Rapp, Brenda

    2014-01-01

    Most cognitive theories of reading and spelling posit modality-specific representations of letter shapes, spoken letter names, and motor plans as well as abstract, amodal letter representations that serve to unify the various modality-specific formats. However, fundamental questions remain regarding the very existence of abstract letter representations, the neuro-topography of the different types of letter representations, and the degree of cortical selectivity for orthographic information. We directly test quantitative models of the similarity/dissimilarity structure of distributed neural representations of letters using Multivariate Pattern Analysis-Representational Similarity Analysis (MVPA-RSA) searchlight methods to analyze the BOLD response recorded from single letter viewing. These analyses reveal a left hemisphere ventral temporal region selectively tuned to abstract letter representations as well as substrates tuned to modality-specific (visual, phonological and motoric) representations of letters. The approaches applied in this research address various shortcoming of previous studies that have investigated these questions and, therefore, the findings we report serve to advance our understanding of the nature and format of the representations that occur within the various sub- regions of the large-scale networks used in reading and spelling. PMID:24321558

  19. An analysis of the size distribution of Italian firms by age

    NASA Astrophysics Data System (ADS)

    Cirillo, Pasquale

    2010-02-01

    In this paper we analyze the size distribution of Italian firms by age. In other words, we want to establish whether the way that the size of firms is distributed varies as firms become old. As a proxy of size we use capital. In [L.M.B. Cabral, J. Mata, On the evolution of the firm size distribution: Facts and theory, American Economic Review 93 (2003) 1075-1090], the authors study the distribution of Portuguese firms and they find out that, while the size distribution of all firms is fairly stable over time, the distributions of firms by age groups are appreciably different. In particular, as the age of the firms increases, their size distribution on the log scale shifts to the right, the left tails becomes thinner and the right tail thicker, with a clear decrease of the skewness. In this paper, we perform a similar analysis with Italian firms using the CEBI database, also considering firms’ growth rates. Although there are several papers dealing with Italian firms and their size distribution, to our knowledge a similar study concerning size and age has not been performed yet for Italy, especially with such a big panel.

  20. Theoretical foundation for measuring the groundwater age distribution.

    SciTech Connect

    Gardner, William Payton; Arnold, Bill Walter

    2014-01-01

    In this study, we use PFLOTRAN, a highly scalable, parallel, flow and reactive transport code to simulate the concentrations of 3H, 3He, CFC-11, CFC-12, CFC-113, SF6, 39Ar, 81Kr, 4He and themean groundwater age in heterogeneous fields on grids with an excess of 10 million nodes. We utilize this computational platform to simulate the concentration of multiple tracers in high-resolution, heterogeneous 2-D and 3-D domains, and calculate tracer-derived ages. Tracer-derived ages show systematic biases toward younger ages when the groundwater age distribution contains water older than the maximum tracer age. The deviation of the tracer-derived age distribution from the true groundwater age distribution increases with increasing heterogeneity of the system. However, the effect of heterogeneity is diminished as the mean travel time gets closer the tracer age limit. Age distributions in 3-D domains differ significantly from 2-D domains. 3D simulations show decreased mean age, and less variance in age distribution for identical heterogeneity statistics. High-performance computing allows for investigation of tracer and groundwater age systematics in high-resolution domains, providing a platform for understanding and utilizing environmental tracer and groundwater age information in heterogeneous 3-D systems. Groundwater environmental tracers can provide important constraints for the calibration of groundwater flow models. Direct simulation of environmental tracer concentrations in models has the additional advantage of avoiding assumptions associated with using calculated groundwater age values. This study quantifies model uncertainty reduction resulting from the addition of environmental tracer concentration data. The analysis uses a synthetic heterogeneous aquifer and the calibration of a flow and transport model using the pilot point method. Results indicate a significant reduction in the uncertainty in permeability with the addition of environmental tracer data, relative

  1. Age- and Hypertension-Associated Protein Aggregates in Mouse Heart Have Similar Proteomic Profiles.

    PubMed

    Ayyadevara, Srinivas; Mercanti, Federico; Wang, Xianwei; Mackintosh, Samuel G; Tackett, Alan J; Prayaga, Sastry V S; Romeo, Francesco; Shmookler Reis, Robert J; Mehta, Jawahar L

    2016-05-01

    Neurodegenerative diseases are largely defined by protein aggregates in affected tissues. Aggregates contain some shared components as well as proteins thought to be specific for each disease. Aggregation has not previously been reported in the normal, aging heart or the hypertensive heart. Detergent-insoluble protein aggregates were isolated from mouse heart and characterized on 2-dimensional gels. Their levels increased markedly and significantly with aging and after sustained angiotensin II-induced hypertension. Of the aggregate components identified by high-resolution proteomics, half changed in abundance with age (392/787) or with sustained hypertension (459/824), whereas 30% (273/901) changed concordantly in both, each P<0.05. One fifth of these proteins were previously associated with age-progressive neurodegenerative or cardiovascular diseases, or both (eg, ApoE, ApoJ, ApoAIV, clusterin, complement C3, and others involved in stress-response and protein-homeostasis pathways). Because fibrosis is a characteristic of both aged and hypertensive hearts, we posited that aging of fibroblasts may contribute to the aggregates observed in cardiac tissue. Indeed, as cardiac myofibroblasts "senesced" (approached their replicative limit) in vitro, they accrued aggregates with many of the same constituent proteins observed in vivo during natural aging or sustained hypertension. In summary, we have shown for the first time that compact (detergent-insoluble) protein aggregates accumulate during natural aging, chronic hypertension, and in vitro myofibroblast senescence, sharing many common proteins. Thus, aggregates that arise from disparate causes (aging, hypertension, and replicative senescence) may have common underlying mechanisms of accrual.

  2. [Physiology of sarcopenia. Similarities and differences with neoplasic cachexia (muscle impairments in cancer and ageing)].

    PubMed

    Argilés, Josep M; Busquets, Silvia; López-Soriano, Francisco J; Figueras, Maite

    2006-05-01

    Muscle wasting during cancer and ageing share many common metabolic pathways and mediators. Due to the size of the population involved, both cancer cachexia and ageing sarcopenia may represent targets for future promising clinical investigations. Cancer cachexia is a syndrome characterized by a marked weight loss, anorexia, asthenia and anemia. In fact, many patients who die with advanced cancer suffer from cachexia. The degree of cachexia is inversely correlated with the survival time of the patient and it always implies a poor prognosis. In recent years, age-related diseases and disabilities have become of major health interest and importance. This holds particularly for muscle wasting, also known as sarcopenia, that decreases the quality of life of the geriatric population, increasing morbidity and decreasing life expectancy. More research should be devoted to the understanding of muscle wasting mediators (associated with both depletion of fat stores and muscular tissue), both in cancer and ageing, in particular the identification of common mediators may prove as a good therapeutic strategies for both prevention and treatment of wasting both in disease and during healthy ageing.

  3. Self-similar distribution of oil spills in European coastal waters

    NASA Astrophysics Data System (ADS)

    Redondo, Jose M; Platonov, Alexei K

    2009-01-01

    Marine pollution has been highlighted thanks to the advances in detection techniques as well as increasing coverage of catastrophes (e.g. the oil tankers Amoco Cadiz, Exxon Valdez, Erika, and Prestige) and of smaller oil spills from ships. The new satellite based sensors SAR and ASAR and new methods of oil spill detection and analysis coupled with self-similar statistical techniques allow surveys of environmental pollution monitoring large areas of the ocean. We present a statistical analysis of more than 700 SAR images obtained during 1996-2000, also comparing the detected small pollution events with the historical databases of great marine accidents during 1966-2004 in European coastal waters. We show that the statistical distribution of the number of oil spills as a function of their size corresponds to Zipf's law, and that the common small spills are comparable to the large accidents due to the high frequency of the smaller pollution events. Marine pollution from tankers and ships, which has been detected as oil spills between 0.01 and 100 km2, follows the marine transit routes. Multi-fractal methods are used to distinguish between natural slicks and spills, in order to estimate the oil spill index in European coastal waters, and in particular, the north-western Mediterranean Sea, which, due to the influence of local winds, shows optimal conditions for oil spill detection.

  4. Aging in the Natural World: Comparative Data Reveal Similar Mortality Patterns Across Primates

    PubMed Central

    Bronikowski, Anne M.; Altmann, Jeanne; Brockman, Diane K.; Cords, Marina; Fedigan, Linda M.; Pusey, Anne; Stoinski, Tara; Morris, William F.; Strier, Karen B.; Alberts, Susan C.

    2012-01-01

    Human senescence patterns—late onset of mortality increase, slow mortality acceleration, and exceptional longevity—are often described as unique in the animal world. Using an individual-based data set from longitudinal studies of wild populations of seven primate species, we show that contrary to assumptions of human uniqueness, human senescence falls within the primate continuum of aging; the tendency for males to have shorter life spans and higher age-specific mortality than females throughout much of adulthood is a common feature in many, but not all, primates; and the aging profiles of primate species do not reflect phylogenetic position. These findings suggest that mortality patterns in primates are shaped by local selective forces rather than phylogenetic history. PMID:21393544

  5. Age-related similarities and differences in first impressions of trustworthiness.

    PubMed

    Bailey, Phoebe E; Szczap, Paulina; McLennan, Skye N; Slessor, Gillian; Ruffman, Ted; Rendell, Peter G

    2016-08-01

    Trust is a particularly under-studied aspect of social relationships in older age. In the current study, young (n = 35) and older adults (n = 35) completed a series of one-shot social economic trust games in which they invested real money with trustees. There were potential gains with each investment and also a risk of losing everything if the trustee was untrustworthy. The reputation and facial appearance of each trustee were manipulated to make them appear more or less trustworthy. Results revealed that young and older adults invest more money with trustees whose facial appearance and reputation indicate that they are trustworthy rather than untrustworthy. However, older adults were more likely than young to invest with trustees who had a reputation for being untrustworthy. We discuss whether age-related differences in responding to negative information may account for an age-related increase in trust, particularly when trusting someone with a reputation for being uncooperative.

  6. Estimating the Age Distribution of Oceanic Dissolved Organic Carbon

    NASA Astrophysics Data System (ADS)

    Follett, C. L.; Forney, D. C.; Repeta, D.; Rothman, D.

    2010-12-01

    Dissolved organic carbon (DOC) is a large, ubiquitous component of open ocean water at all depths and impacts atmospheric carbon dioxide levels at both short and long timescales. It is currently believed that oceanic DOC contains a multi-thousand-year-old refractory deep-water component which is mixed with a young labile component in surface waters. Unfortunately, the only evidence for this comes from a few isolated depth profiles of both DOC concentration and bulk radiocarbon. Although the profile data is consistent with a two-component mixing model, directly separating the two components has proven to be a challenge. We explore the validity of the two component mixing model by directly estimating the age distribution of oceanic DOC. The two-component model suggests that the age distribution is composed of two distinct peaks. In order to obtain an estimate of the age distribution we first record changes in both concentration and percent radiocarbon as a sample is oxidized under ultra-violet radiation [1]. We formulate a mathematical model relating the age distribution to these changes, assuming that they result from components of different radiocarbon age and UV-reactivity. This allows us to numerically invert the data and estimate the age distribution. We apply our procedure to DOC samples collected from three distinct depths (50, 500, and 2000 meters) in the north-central Pacific Ocean. [1] S.R. Beaupre, E.R.M. Druffel, and S. Griffin. A low-blank photochemical extraction system for concentration and isotopic analyses of marine dissolved organic carbon. Limnol. Oceanogr. Methods, 5:174-184, 2007.

  7. Effects of intraborehole flow on groundwater age distribution

    USGS Publications Warehouse

    Zinn, B.A.; Konikow, L.F.

    2007-01-01

    Environmental tracers are used to estimate groundwater ages and travel times, but the strongly heterogeneous nature of many subsurface environments can cause mixing between waters of highly disparate ages, adding additional complexity to the age-estimation process. Mixing may be exacerbated by the presence of wells because long open intervals or long screens with openings at multiple depths can transport water and solutes rapidly over a large vertical distance. The effect of intraborehole flow on groundwater age was examined numerically using direct age transport simulation coupled with the Multi-Node Well Package of MODFLOW. Ages in a homogeneous, anisotropic aquifer reached a predevelopment steady state possessing strong depth dependence. A nonpumping multi-node well was then introduced in one of three locations within the system. In all three cases, vertical transport along the well resulted in substantial changes in age distributions within the system. After a pumping well was added near the nonpumping multi-node well, ages were further perturbed by a flow reversal in the nonpumping multi-node well. Results indicated that intraborehole flow can substantially alter groundwater ages, but the effects are highly dependent on local or regional flow conditions and may change with time. ?? Springer-Verlag 2007.

  8. Pension benefits among the aged: conflicting measures, unequal distributions.

    PubMed

    Woods, J R

    1996-01-01

    Estimates of total benefits paid by employer sponsored pension plans seem to vary widely between different data sources and measures. Such discrepancies have been used to support differing conclusions about the effectiveness of the pension system. This article examines several measures of aggregate pension benefits in 1990, a year particularly rich in available data. Exploratory analysis suggests that the greatest source of discrepancy lies in differing treatments of lump-sum distributions, although the study also identifies several other types of payments that are variously, and erroneously, counted as pension income. Age of recipients is an important factor in analyzing different measures of aggregate pension benefits; discrepancies are much smaller among the aged than in the population as a whole. The analysis also provides new evidence about the unequal distribution of pension benefits among the aged, confirming from two data sources that benefits are heavily concentrated among higher income groups.

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

    NASA Astrophysics Data System (ADS)

    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.

  10. Prolactin and growth hormone affect metaphase-II chromosomes in aging oocytes via cumulus cells using similar signaling pathways

    PubMed Central

    Lebedeva, Irina Y.; Singina, Galina N.; Lopukhov, Alexander V.; Shedova, Ekaterina N.; Zinovieva, Natalia A.

    2015-01-01

    General senescence of the adult organism is closely connected with reproductive one. Meanwhile, the age-related reduction in the female fertility is primarily associated with a decline in the gamete quality. Molecular and cellular changes in oocytes of old mammalian females are very similar to those occurring during aging of matured ova of their young counterparts, suggesting similarities in underlying mechanisms. The aim of the present work was to study actions of two related pituitary hormones, prolactin (PRL) and growth hormone (GH), on age-associated modifications of metaphase-II (M-II) chromosomes in bovine oocytes using a model of the prolonged culture. We analyzed: (1) effects of PRL and GH on abnormal changes in the chromosome morphology in aging matured oocytes and the role of cumulus cells in these effects and (2) signaling pathways involved in the hormone actions. During the prolonged culture of oocytes, a gradual rise in the frequency of destructive modifications of M-II chromosomes was revealed. In the case of cumulus-enclosed oocytes (CEOs), PRL and GH exerted dose-dependent biphasic effects on the frequency of these modifications. Both PRL (50 ng/ml) and GH (10 ng/ml) decelerated the abnormal chromosome changes in CEOs, but did not affect the chromosome configuration in denuded oocytes. Concurrently, the presence of PRL and GH receptors in cumulus cells surrounding matured oocytes was demonstrated. Attenuating effects of both hormones on the chromosome modifications in aging CEOs were abolished by PP2 (an inhibitor of Src-family tyrosine kinases), triciribine (an inhibitor of Akt kinase), and calphostin C (a protein kinase C inhibitor). Our findings indicate that PRL and GH can exert the similar decelerating action on age-associated alterations in the M-II chromosome morphology in bovine ova, which is mediated by cumulus cells and may be related to activation of Src-family tyrosine kinases as well as Akt- and protein kinase C-dependent signal

  11. Age related distributive justice and claims on resources.

    PubMed

    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.

  12. Target-distractor similarity has a larger impact on visual search in school-age children than spacing.

    PubMed

    Huurneman, Bianca; Boonstra, F Nienke

    2015-01-22

    In typically developing children, crowding decreases with increasing age. The influence of target-distractor similarity with respect to orientation and element spacing on visual search performance was investigated in 29 school-age children with normal vision (4- to 6-year-olds [N = 16], 7- to 8-year-olds [N = 13]). Children were instructed to search for a target E among distractor Es (feature search: all flanking Es pointing right; conjunction search: flankers in three orientations). Orientation of the target was manipulated in four directions: right (target absent), left (inversed), up, and down (vertical). Spacing was varied in four steps: 0.04°, 0.5°, 1°, and 2°. During feature search, high target-distractor similarity had a stronger impact on performance than spacing: Orientation affected accuracy until spacing was 1°, and spacing only influenced accuracy for identifying inversed targets. Spatial analyses showed that orientation affected oculomotor strategy: Children made more fixations in the "inversed" target area (4.6) than the vertical target areas (1.8 and 1.9). Furthermore, age groups differed in fixation duration: 4- to 6-year-old children showed longer fixation durations than 7- to 8-year-olds at the two largest element spacings (p = 0.039 and p = 0.027). Conjunction search performance was unaffected by spacing. Four conclusions can be drawn from this study: (a) Target-distractor similarity governs visual search performance in school-age children, (b) children make more fixations in target areas when target-distractor similarity is high, (c) 4- to 6-year-olds show longer fixation durations than 7- to 8-year-olds at 1° and 2° element spacing, and (d) spacing affects feature but not conjunction search-a finding that might indicate top-down control ameliorates crowding in children.

  13. HALO-TO-HALO SIMILARITY AND SCATTER IN THE VELOCITY DISTRIBUTION OF DARK MATTER

    SciTech Connect

    Mao, Yao-Yuan; Strigari, Louis E.; Wechsler, Risa H.; Hahn, Oliver; Wu, Hao-Yi

    2013-02-10

    We examine the velocity distribution function (VDF) in dark matter halos from Milky Way to cluster mass scales. We identify an empirical model for the VDF with a wider peak and a steeper tail than a Maxwell-Boltzmann distribution, and discuss physical explanations. We quantify sources of scatter in the VDF of cosmological halos and their implication for direct detection of dark matter. Given modern simulations and observations, we find that the most significant uncertainty in the VDF of the Milky Way arises from the unknown radial position of the solar system relative to the dark matter halo scale radius.

  14. Distribution system water age can create premise plumbing corrosion hotspots.

    PubMed

    Masters, Sheldon; Parks, Jeffrey; Atassi, Amrou; Edwards, Marc A

    2015-09-01

    Cumulative changes in chemical and biological properties associated with higher "water age" in distribution systems may impact water corrosivity and regulatory compliance with lead and copper action levels. The purpose of this study was to examine the effects of water age and chemistry on corrosivity of various downstream premise plumbing pipe materials and configurations using a combination of controlled laboratory studies and a field survey. Examination of lead pipe, copper pipe with lead solder, and leaded brass materials in a replicated lab rig simulating premise plumbing stagnation events indicated that lead or copper release could increase as much as ∼440 % or decrease as much as 98 % relative to water treatment plant effluent. In field studies at five utilities, trends in lead and copper release were highly dependent on circumstance; for example, lead release increased with water age in 13 % of cases and decreased with water age in 33 % of conditions tested. Levels of copper in the distribution system were up to 50 % lower and as much as 30 % higher relative to levels at the treatment plant. In many cases, high-risks of elevated lead and copper did not co-occur, demonstrating that these contaminants will have to be sampled separately to identify "worst case" conditions for human exposure and monitoring. PMID:26251058

  15. Distribution system water age can create premise plumbing corrosion hotspots.

    PubMed

    Masters, Sheldon; Parks, Jeffrey; Atassi, Amrou; Edwards, Marc A

    2015-09-01

    Cumulative changes in chemical and biological properties associated with higher "water age" in distribution systems may impact water corrosivity and regulatory compliance with lead and copper action levels. The purpose of this study was to examine the effects of water age and chemistry on corrosivity of various downstream premise plumbing pipe materials and configurations using a combination of controlled laboratory studies and a field survey. Examination of lead pipe, copper pipe with lead solder, and leaded brass materials in a replicated lab rig simulating premise plumbing stagnation events indicated that lead or copper release could increase as much as ∼440 % or decrease as much as 98 % relative to water treatment plant effluent. In field studies at five utilities, trends in lead and copper release were highly dependent on circumstance; for example, lead release increased with water age in 13 % of cases and decreased with water age in 33 % of conditions tested. Levels of copper in the distribution system were up to 50 % lower and as much as 30 % higher relative to levels at the treatment plant. In many cases, high-risks of elevated lead and copper did not co-occur, demonstrating that these contaminants will have to be sampled separately to identify "worst case" conditions for human exposure and monitoring.

  16. Effects of Contextual Similarity and Target-Repetition Proportion on Negative Priming in RT Distributional Analyses

    ERIC Educational Resources Information Center

    Tse, Chi-Shing; Hutchison, Keith A.; Li, Yongna

    2011-01-01

    Participants' reaction time (RT) data in a prime-probe flanker task (e.g., ABA-CAC) were analyzed in terms of the characteristics of RT distribution to examine possible mechanisms that produce negative priming. When the prime and probe were presented in the same context and the proportion of repetition-target trials (TRP) was 0.33, negative…

  17. Age changes in the distribution of visual attention.

    PubMed

    McCalley, L T; Bouwhuis, D G; Juola, J F

    1995-11-01

    Two experiments examined adult age differences in the controlled allocation of visual selective attention. Both experiments were identical with the exception of the stimulus display where targets and distractors were linearly increased with eccentricity in Experiment 2. A spatial cuing task was used with four cue-target presentation intervals (SOAs) of 250, 500, 1000, and 2000 msec (Experiment 1) and 250, 500, 750, and 1000 msec (Experiment 2). Results were fit to three quantitative models based on attentional distribution metaphors (spotlight, zoom lens, and ring) in order to determine the best fitting model of attentional distribution. Data from Experiment 1 indicated that older subjects distributed attention in a qualitatively different manner than younger subjects and suggested a different time course of processing. When stimuli visibility was controlled a single flexible resource allocation (ring) model of attention could account for the results of both age groups at all SOAs. Results further suggested that older adults employ compensatory strategies to offset visual processing difficulties. PMID:7583811

  18. Mass/age distribution of organic carbon for the Phanerozoic

    SciTech Connect

    Hay, W.W.; Wold, C.N. Geomar, Kiel )

    1991-03-01

    The mass/age distribution of organic carbon in Phanerozoic sedimentary rocks is dominated by disseminated organic carbon in pelitic rocks. Even during the major times of coal formation, the mass of organic carbon in coal is small compared with that included in fine-grained marine sediments. The mass/age distribution shows maxima in the Middle and Late Ordovician, Late Devonian, Late Jurassic and Early Cretaceous, and Neogene. Minima in accumulation of organic carbon mark the Early Ordovician, Early Devonian, Permian and Triassic, Late Cretaceous and Paleogene. Reconstruction of the ancient fluxes of organic carbon into the sediments shows that the distribution is almost symmetrical about the Paleozoic-Mesozoic boundary. Major hydrocarbon source rock accumulations coincide with peaks of organic carbon deposition, but modes of formation of the source rocks at each peak may have been different. The peaks of organic carbon accumulation correspond to times of flooding of the continents. The Ordovician, Late Jurassic-Early Cretaceous peaks also correspond to an increase in the ratio of carbon being deposited as organic carbon relative to that deposited as carbonate; they also correspond to times of deposition of large amounts of siliceous sediment. The Lake Devonian peak also formed at a time of flooding of the continents, but shows a low ratio of organic carbon to carbonate, and few siliceous rocks accumulated contemporaneously. The Neogene peak may represent a fundamentally different accumulation mechanism, resulting mostly from coastal upwelling during a time of emergence of the continents.

  19. A statistical approach to modelling permafrost distribution in the European Alps or similar mountain ranges

    NASA Astrophysics Data System (ADS)

    Boeckli, L.; Brenning, A.; Gruber, S.; Noetzli, J.

    2012-01-01

    Estimates of permafrost distribution in mountain regions are important for the assessment of climate change effects on natural and human systems. In order to make permafrost analyses and the establishment of guidelines for e.g. construction or hazard assessment comparable and compatible between regions, one consistent and traceable model for the entire Alpine domain is required. For the calibration of statistical models, the scarcity of suitable and reliable information about the presence or absence of permafrost makes the use of large areas attractive due to the larger data base available. We present a strategy and method for modelling permafrost distribution of entire mountain regions and provide the results of statistical analyses and model calibration for the European Alps. Starting from an integrated model framework, two statistical sub-models are developed, one for debris-covered areas (debris model) and one for steep bedrock (rock model). They are calibrated using rock glacier inventories and rock surface temperatures. To support the later generalization to surface characteristics other than those available for calibration, so-called offset terms have been introduced into the model that allow doing this in a transparent and traceable manner. For the debris model a generalized linear mixed-effect model (GLMM) is used to predict the probability of a rock glacier being intact as opposed to relict. It is based on the explanatory variables mean annual air temperature (MAAT), potential incoming solar radiation (PISR) and the mean annual sum of precipitation (PRECIP), and achieves an excellent discrimination (area under the receiver-operating characteristic, AUROC = 0.91). Surprisingly, the probability of a rock glacier being intact is positively associated with increasing PRECIP for given MAAT and PISR conditions. The rock model is based on a linear regression and was calibrated with mean annual rock surface temperatures (MARST). The explanatory variables are MAAT

  20. Learning of a simple grapho-motor task by young children and adults: similar acquisition but age-dependent retention

    PubMed Central

    Julius, Mona S.; Adi-Japha, Esther

    2015-01-01

    Many new skills are acquired during early childhood. Typical laboratory skill learning tasks are not applicable for developmental studies that involve children younger than 8 years of age. It is not clear whether young children and adults share a basic underlying skill learning mechanism. In the present study, the learning and retention of a simple grapho-motor pattern were studied in three age groups: 5–6, 7–8, and 19–29 years. Each block of the task consists of identical patterns arranged in a spaced writing array. Progression across the block involves on-page movements while producing the pattern, and off-page movements between patterns. The participants practiced the production of the pattern using a digitizing tablet and were tested at 24 h and 2 weeks post-practice. All age groups produced the task blocks more quickly with practice, and the learning rate was inversely related to the initial production time. All groups exhibited additional gains 24 h post-practice that were well-retained 2 weeks later. The accuracy of the participants was maintained throughout the 2-weeks period. These findings suggest that young children and young adults use a similar mechanism when learning the task. Nevertheless, the 6-years-old spent more time off-page during retention testing than when tested at 24 h post-practice, thus supporting the notion that an age advantage may exists in the long-term retention of skills due to planning-dependent aspects. PMID:25798120

  1. Negative strain rate sensitivity in bulk metallic glass and its similarities with the dynamic strain aging effect during deformation

    SciTech Connect

    Dalla Torre, Florian H.; Dubach, Alban; Siegrist, Marco E.; Loeffler, Joerg F.

    2006-08-28

    Detailed investigations were carried out on the deformation behavior of Zr-based monolithic bulk metallic glass and bulk metallic glass matrix composites. The latter, due to splitting and multiplication of shear bands, exhibits larger compressive strains than the former, without significant loss of strength. Serrated flow in conjunction with a negative strain rate sensitivity was observed in both materials. This observation, together with an increase in stress drops with increasing strain and their decrease with increasing strain rate, indicates phenomenologically close similarities with the dynamic strain aging deformation mechanism known for crystalline solids. The micromechanical mechanism of a shear event is discussed in light of these results.

  2. Similarities and differences of metal distributions in the tissues of molluscs by using multivariate analyses.

    PubMed

    Yap, Chee Kong; Edward, Franklin Berandah; Tan, Soon Guan

    2010-06-01

    Multivariate analysis including correlation, multiple stepwise linear regression, and cluster analyses were applied to investigate the heavy metal concentrations (Cd, Cu, Fe, Ni, Pb, and Zn) in the different parts of bivalves and gastropods. It was also aimed to distinguish statistically the differences between the marine bivalves and the gastropods with regards to the accumulation of heavy metals in the different tissues. The different parts of four species of bivalves and four species of gastropods were obtained and analyzed for heavy metals. The multivariate analyses were then applied on the data. From the multivariate analyses conducted, there were correlations found between the soft tissues of bivalves and gastropods, but none was found between the shells and the soft tissues of most of the molluscs (except for Cerithidea obtusa and Puglina cochlidium). The significant correlations (P < 0.05) found between the soft tissues were further complemented by the multiple stepwise linear regressions where heavy metals in the total soft tissues were influenced by the accumulation in the different types of soft tissues. The present study found that the distributions of heavy metals in the different parts of molluscs were related to their feeding habits and living habitats. The statistical approaches proposed in this study are recommended for use in biomonitoring studies, since multivariate analyses can reduce the cost and time involved in identifying an effective tissue to monitor the heavy metal(s) bioavailability and contamination in tropical coastal waters.

  3. Weighting training images by maximizing distribution similarity for supervised segmentation across scanners.

    PubMed

    van Opbroek, Annegreet; Vernooij, Meike W; Ikram, M Arfan; de Bruijne, Marleen

    2015-08-01

    Many automatic segmentation methods are based on supervised machine learning. Such methods have proven to perform well, on the condition that they are trained on a sufficiently large manually labeled training set that is representative of the images to segment. However, due to differences between scanners, scanning parameters, and patients such a training set may be difficult to obtain. We present a transfer-learning approach to segmentation by multi-feature voxelwise classification. The presented method can be trained using a heterogeneous set of training images that may be obtained with different scanners than the target image. In our approach each training image is given a weight based on the distribution of its voxels in the feature space. These image weights are chosen as to minimize the difference between the weighted probability density function (PDF) of the voxels of the training images and the PDF of the voxels of the target image. The voxels and weights of the training images are then used to train a weighted classifier. We tested our method on three segmentation tasks: brain-tissue segmentation, skull stripping, and white-matter-lesion segmentation. For all three applications, the proposed weighted classifier significantly outperformed an unweighted classifier on all training images, reducing classification errors by up to 42%. For brain-tissue segmentation and skull stripping our method even significantly outperformed the traditional approach of training on representative training images from the same study as the target image. PMID:26210914

  4. Distribution of HLA haplotypes across Japanese Archipelago: similarity, difference and admixture.

    PubMed

    Nakaoka, Hirofumi; Inoue, Ituro

    2015-11-01

    The human leukocyte antigen (HLA) region is the most polymorphic region in the human genome. The polymorphic nature of the HLA region is thought to have been shaped from balancing selection. The complex migration events during the Out-of-Africa expansion have influenced geographic patterns of HLA allele frequencies and diversities across present-day human populations. Differences in the HLA allele frequency may contribute geographic differences in the susceptibility to many diseases, such as infectious, autoimmune and metabolic diseases. Here we briefly reviewed characteristics of frequency distribution of HLA alleles and haplotypes in Japanese population. A large part of HLA alleles and haplotypes that are common in Japanese are shared with neighboring Asian populations. The differentiations in HLA alleles and haplotypes across Japanese regional populations may provide clues to model for peopling of Japanese Archipelago and for design of genetic association studies. Finally, we introduce recent topics that new HLA alleles derived from ancient admixtures with Neanderthals and Denisovans are thought to have played an important role in the adaptation of modern humans to local pathogens during Out-of-Africa expansion. PMID:26202576

  5. Mind the gap: the distributional effects of raising the early eligibility age and full retirement age.

    PubMed

    Olsen, Anya

    2012-01-01

    Policymakers have proposed increases to the early eligibility age (EEA) and/or full retirement age (FRA) to address increasing life expectancy and Social Security solvency issues. This analysis uses the Social Security Administration's Modeling Income in the Near Term, version 6 (MINT6) model to compare three retirement-age increases suggested by the Social Security Advisory Board: increase the gap between the EEA and FRA by raising only the FRA, increase both the EEA and FRA to maintain a 4-year gap between them, and increase both the EEA and FRA to maintain a 5-year gap between them. Although all three options would improve system solvency by similar proportions, their effect on individual beneficiaries in the future would vary. Benefit reductions are greater under the proposals with more months between the EEA and FRA, while the option that maintains a 4-year gap results in benefit increases for some beneficiaries compared with current law. PMID:23397744

  6. Effect of river sediment on phosphorus chemistry of similarly aged natural and created wetlands in the Atchafalaya Delta, Louisiana, USA.

    PubMed

    Poach, M E; Faulkner, S P

    2007-01-01

    The goal of wetland creation is to produce an artificial wetland that functions as a natural wetland. Studies comparing created wetlands to similarly aged natural wetlands provide important information about creation techniques and their improvement so as to attain that goal. We hypothesized that differences in sediment phosphorus accretion, deposition, and chemistry between created and natural wetlands in the Atchafalaya Delta, Louisiana, USA were a function of creation technique and natural river processes. Sediment deposition was determined with feldspar marker horizons located in created and natural wetlands belonging to three age classes (<3, 5-10, and 15-20 yr old). Phosphorus fractions were measured in these deposited sediments and in suspended and bedload sediment from the Atchafalaya River. Bedload sediment had significantly lower iron- and aluminum-bound, reductant-soluble, and total phosphorus than suspended sediment due to its high sand percentage. This result indicates that wetlands artificially created in the Atchafalaya Delta using bedload sediment will initially differ from natural wetlands of the same age. Even so, similarities between the mudflat stratum of the <1- to 3-yr-old created wetland and the mudflat stratum of the 15- to 20-yr-old natural wetland support the contention that created wetlands in the Atchafalaya Delta can develop natural characteristics through the deposition of river suspended sediment. Differences between three created wetland strata, the 15- to 20-yr-old willow stratum and the <1- to 3-yr-old willow and mixed marsh strata, and their natural counterparts were linked to design elements of the created wetlands that prevented the direct deposition of the river's suspended sediment.

  7. Effect of river sediment on phosphorus chemistry of similarly aged natural and created wetlands in the Atchafalaya Delta, Louisiana, USA

    USGS Publications Warehouse

    Poach, M.E.; Faulkner, S.P.

    2007-01-01

    The goal of wetland creation is to produce an artificial wetland that functions as a natural wetland. Studies comparing created wetlands to similarly aged natural wetlands provide important information about creation techniques and their improvement so as to attain that goal. We hypothesized that differences in sediment phosphorus accretion, deposition, and chemistry between created and natural wetlands in the Atchafalaya Delta, Louisiana, USA were a function of creation technique and natural river processes. Sediment deposition was determined with feldspar marker horizons located in created and natural wetlands belonging to three age classes (<3, 5-10, and 15-20 yr old). Phosphorus fractions were measured in these deposited sediments and in suspended and bedload sediment from the Atchafalaya River. Bedload sediment had significantly lower iron- and aluminum-bound, reductant-soluble, and total phosphorus than suspended sediment due to its high sand percentage. This result indicates that wetlands artificially created in the Atchafalaya Delta using bedload sediment will initially differ from natural wetlands of the same age. Even so, similarities between the mudflat stratum of the <1- to 3-yr-old created wetland and the mudflat stratum of the 15- to 20-yr-old natural wetland support the contention that created wetlands in the Atchafalaya Delta can develop natural characteristics through the deposition of river suspended sediment. Differences between three created wetland strata, the 15- to 20-yr-old willow stratum and the < 1- to 3-yr-old willow and mixed marsh strata, and their natural counterparts were linked to design elements of the created wetlands that prevented the direct deposition of the river's suspended sediment. ?? ASA, CSSA, SSSA.

  8. Similarities in Gene Expression Profiles during In Vitro Aging of Primary Human Embryonic Lung and Foreskin Fibroblasts

    PubMed Central

    Marthandan, Shiva; Priebe, Steffen; Baumgart, Mario; Groth, Marco; Cellerino, Alessandro; Guthke, Reinhard; Hemmerich, Peter; Diekmann, Stephan

    2015-01-01

    Replicative senescence is of fundamental importance for the process of cellular aging, since it is a property of most of our somatic cells. Here, we elucidated this process by comparing gene expression changes, measured by RNA-seq, in fibroblasts originating from two different tissues, embryonic lung (MRC-5) and foreskin (HFF), at five different time points during their transition into senescence. Although the expression patterns of both fibroblast cell lines can be clearly distinguished, the similar differential expression of an ensemble of genes was found to correlate well with their transition into senescence, with only a minority of genes being cell line specific. Clustering-based approaches further revealed common signatures between the cell lines. Investigation of the mRNA expression levels at various time points during the lifespan of either of the fibroblasts resulted in a number of monotonically up- and downregulated genes which clearly showed a novel strong link to aging and senescence related processes which might be functional. In terms of expression profiles of differentially expressed genes with age, common genes identified here have the potential to rule the transition into senescence of embryonic lung and foreskin fibroblasts irrespective of their different cellular origin. PMID:26339636

  9. Consumption of Milk Protein or Whey Protein Results in a Similar Increase in Muscle Protein Synthesis in Middle Aged Men.

    PubMed

    Mitchell, Cameron J; McGregor, Robin A; D'Souza, Randall F; Thorstensen, Eric B; Markworth, James F; Fanning, Aaron C; Poppitt, Sally D; Cameron-Smith, David

    2015-10-21

    The differential ability of various milk protein fractions to stimulate muscle protein synthesis (MPS) has been previously described, with whey protein generally considered to be superior to other fractions. However, the relative ability of a whole milk protein to stimulate MPS has not been compared to whey. Sixteen healthy middle-aged males ingested either 20 g of milk protein (n = 8) or whey protein (n = 8) while undergoing a primed constant infusion of ring (13)C₆ phenylalanine. Muscle biopsies were obtained 120 min prior to consumption of the protein and 90 and 210 min afterwards. Resting myofibrillar fractional synthetic rates (FSR) were 0.019% ± 0.009% and 0.021% ± 0.018% h(-1) in the milk and whey groups respectively. For the first 90 min after protein ingestion the FSR increased (p < 0.001) to 0.057% ± 0.018% and 0.052% ± 0.024% h(-1) in the milk and whey groups respectively with no difference between groups (p = 0.810). FSR returned to baseline in both groups between 90 and 210 min after protein ingestion. Despite evidence of increased rate of digestion and leucine availability following the ingestion of whey protein, there was similar activation of MPS in middle-aged men with either 20 g of milk protein or whey protein.

  10. Consumption of Milk Protein or Whey Protein Results in a Similar Increase in Muscle Protein Synthesis in Middle Aged Men

    PubMed Central

    Mitchell, Cameron J.; McGregor, Robin A.; D’Souza, Randall F.; Thorstensen, Eric B.; Markworth, James F.; Fanning, Aaron C.; Poppitt, Sally D.; Cameron-Smith, David

    2015-01-01

    The differential ability of various milk protein fractions to stimulate muscle protein synthesis (MPS) has been previously described, with whey protein generally considered to be superior to other fractions. However, the relative ability of a whole milk protein to stimulate MPS has not been compared to whey. Sixteen healthy middle-aged males ingested either 20 g of milk protein (n = 8) or whey protein (n = 8) while undergoing a primed constant infusion of ring 13C6 phenylalanine. Muscle biopsies were obtained 120 min prior to consumption of the protein and 90 and 210 min afterwards. Resting myofibrillar fractional synthetic rates (FSR) were 0.019% ± 0.009% and 0.021% ± 0.018% h−1 in the milk and whey groups respectively. For the first 90 min after protein ingestion the FSR increased (p < 0.001) to 0.057% ± 0.018% and 0.052% ± 0.024% h−1 in the milk and whey groups respectively with no difference between groups (p = 0.810). FSR returned to baseline in both groups between 90 and 210 min after protein ingestion. Despite evidence of increased rate of digestion and leucine availability following the ingestion of whey protein, there was similar activation of MPS in middle-aged men with either 20 g of milk protein or whey protein. PMID:26506377

  11. Significance tests and weighted values for AFLP similarities, based on Arabidopsis in silico AFLP fragment length distributions.

    PubMed Central

    Koopman, Wim J M; Gort, Gerrit

    2004-01-01

    Many AFLP studies include relatively unrelated genotypes that contribute noise to data sets instead of signal. We developed: (1) estimates of expected AFLP similarities between unrelated genotypes, (2) significance tests for AFLP similarities, enabling the detection of unrelated genotypes, and (3) weighted similarity coefficients, including band position information. Detection of unrelated genotypes and use of weighted similarity coefficients will make the analysis of AFLP data sets more informative and more reliable. Test statistics and weighted coefficients were developed for total numbers of shared bands and for Dice, Jaccard, Nei and Li, and simple matching (dis)similarity coefficients. Theoretical and in silico AFLP fragment length distributions (FLDs) were examined as a basis for the tests. The in silico AFLP FLD based on the Arabidopsis thaliana genome sequence was the most appropriate for angiosperms. The G + C content of the selective nucleotides in the in silico AFLP procedure significantly influenced the FLD. Therefore, separate test statistics were calculated for AFLP procedures with high, average, and low G + C contents in the selective nucleotides. The test statistics are generally applicable for angiosperms with a G + C content of approximately 35-40%, but represent conservative estimates for genotypes with higher G + C contents. For the latter, test statistics based on a rice genome sequence are more appropriate. PMID:15342529

  12. Malattia Leventinese/Doyne Honeycomb Retinal Dystrophy: Similarities to Age-Related Macular Degeneration and Potential Therapies.

    PubMed

    Hulleman, John D

    2016-01-01

    Fibulin-3 (F3) is a secreted, disulfide-rich glycoprotein which is expressed in a variety of tissues within the body, including the retina. An Arg345Trp (R345W) mutation in F3 was identified as the cause of a rare retinal dystrophy, Malattia Leventinese/Doyne Honeycomb Retinal Dystrophy (ML/DHRD). ML/DHRD shares many phenotypic similarities with age-related macular degeneration (AMD). The most prominent feature of ML/DHRD is the development of radial or honeycomb patterns of drusen which can develop as early as adolescence. Two independent mouse models of ML/DHRD show evidence of complement activation as well as retinal pigment epithelium (RPE) atrophy, strengthening the phenotypic connection with AMD. Because of its similarities with AMD, ML/DHRD is receiving increasing interest as a potential surrogate disease to study the underpinnings of AMD. This mini-review summarizes the current knowledge of F3 and points toward potential therapeutic strategies which directly or indirectly target cellular dysfunction associated with R345W F3.

  13. Effects of surface source/sink distributions on the flux-gradient similarity in the unstable surface layer

    NASA Astrophysics Data System (ADS)

    Huo, Qing; Cai, Xuhui; Kang, Ling; Zhang, Hongsheng; Song, Yu

    2015-01-01

    Based on the micrometeorological measurements at a heterogeneous farmland in the North China Plain, this study focused on the effects of surface source/sink distributions on the flux-gradient similarity theory in the unstable surface layer. Firstly, the quality of the micrometeorological measurements was evaluated by the analysis of the surface energy balance closure and the integral turbulence characteristics. In general, a 22 % deficit of energy balance was found at this site, with the sum of sensible and latent heat being smaller than the available energy. The normalized standard deviations of turbulent quantities behaved in accordance with Monin-Obukhov similarity theory. However, slight departures from the classical formulations might be caused by the surface heterogeneity. Then, the applicability of flux-gradient similarity over the heterogeneous surface was examined. The observed normalized wind gradients agreed with the classical universal function established over homogeneous surface. However, due to the effects of surface source/sink distributions, the observed normalized humidity and temperature gradients deviated from the classical universal functions. Our study shows that the classical universal functions, when adjusted by a coefficient considering the effects of surface heterogeneity, can be utilized to estimate fluxes via gradient method even though over the heterogeneous surface. This adjustment coefficient was found to decrease linearly from unity with the increase of the absolute value of the vertical flux divergence.

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

    PubMed

    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.

  15. Circulatory response to single circuit weight and walking training sessions of similar energy cost in middle-aged overweight females.

    PubMed

    Jürimäe, T; Jürimäe, J; Pihl, E

    2000-03-01

    The aim of this study was to compare circulatory responses to circuit weight (CWT) and aerobic walking training sessions of similar energy cost in middle-aged overweight females. Thirty-three middle-aged pre-menopausal females participated in the experiment. They were divided into overweight (n=18, 36.2 +/- 6.3 years, 166.3 +/- 8.0 cm, 83.5 +/- 9.7 kg, BMI 30.2 +/- 3.1 kg m-2) and non-overweight control (n=15, 34.1 +/- 6.3 years, 165.0 +/- 5.6 cm, 61.6 +/- 5.0 kg, BMI 22.7 +/- 1.5 kg m-2) groups. Individual physical working capacity (PWC) was measured using the cycle ergometer test (calculated at the level of predicted HRmax (205 - (1/2) age). A CWT session consisted of leg extension, bench press, sit-ups and leg press exercises. The subjects performed four circuits at the maximal possible speed, using a work-to-rest ratio of 60 s. Blood pressure (BP) was measured during every rest period between the exercises, and the heart rate (HR) was recorded continuously during the whole CWT programme. During the walking training session, the subjects walked as fast as possible on the indoor track. The total energy cost of the walking training session was the same as during the CWT session, approximately 270 kcal, and was controlled by a CALTRAC accelerometer. HR and BP were measured every 5 min during the walking training session. The PWC index was significantly (P<0.05) higher in the overweight group in comparison with the control females (215.4 +/- 76.1 and 187.9 +/- 42.4 W, respectively). The resting BP was normal in both groups (<140/90 mmHg). HR was between 120 and 140 beats min-1 during CWT and walking sessions. There were no differences in BP during both training sessions in overweight and control subjects. It was concluded that both CWT and walking training sessions were acceptable forms of physical activity to increase cardiovascular fitness in middle-aged overweight and normal body weight females.

  16. Aged boreal biomass-burning aerosol size distributions from BORTAS 2011

    NASA Astrophysics Data System (ADS)

    Sakamoto, K. M.; Allan, J. D.; Coe, H.; Taylor, J. W.; Duck, T. J.; Pierce, J. R.

    2015-02-01

    Biomass-burning aerosols contribute to aerosol radiative forcing on the climate system. The magnitude of this effect is partially determined by aerosol size distributions, which are functions of source fire characteristics (e.g. fuel type, MCE) and in-plume microphysical processing. The uncertainties in biomass-burning emission number-size distributions in climate model inventories lead to uncertainties in the CCN (cloud condensation nuclei) concentrations and forcing estimates derived from these models. The BORTAS-B (Quantifying the impact of BOReal forest fires on Tropospheric oxidants over the Atlantic using Aircraft and Satellite) measurement campaign was designed to sample boreal biomass-burning outflow over eastern Canada in the summer of 2011. Using these BORTAS-B data, we implement plume criteria to isolate the characteristic size distribution of aged biomass-burning emissions (aged ~ 1-2 days) from boreal wildfires in northwestern Ontario. The composite median size distribution yields a single dominant accumulation mode with Dpm = 230 nm (number-median diameter) and σ = 1.5, which are comparable to literature values of other aged plumes of a similar type. The organic aerosol enhancement ratios (ΔOA / ΔCO) along the path of Flight b622 show values of 0.09-0.17 μg m-3 ppbv-1 (parts per billion by volume) with no significant trend with distance from the source. This lack of enhancement ratio increase/decrease with distance suggests no detectable net OA (organic aerosol) production/evaporation within the aged plume over the sampling period (plume age: 1-2 days), though it does not preclude OA production/loss at earlier stages. A Lagrangian microphysical model was used to determine an estimate of the freshly emitted size distribution corresponding to the BORTAS-B aged size distributions. The model was restricted to coagulation and dilution processes based on the insignificant net OA production/evaporation derived from the ΔOA / ΔCO enhancement ratios. We

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

    NASA Technical Reports Server (NTRS)

    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.

  18. Confabulation in healthy aging is related to interference of overlearned, semantically similar information on episodic memory recall.

    PubMed

    Dalla Barba, Gianfranco; Attali, Eve; La Corte, Valentina

    2010-07-01

    Normal aging is characterized by reduced performance on tasks of long-term memory. Older adults (OA) not only show reduced performance on tasks of recall and recognition memory, but also, compared to young adults (YA), are more vulnerable to memory distortions. In this study we describe the performance of a group of OA and a group of YA on the recall of three different types of story: a previously unknown story, a well-known fairy tale (Sleeping Beauty), and a modified well-known fairy tale (Little Red Riding Hood is not eaten by the wolf). The aim of our study was to test the hypothesis that in OA strongly represented, overlearned information interferes with episodic recall-that is, the retrieval of specific, unique past episodes. OA produced significantly more confabulations than YA and in particular in the recall of the modified fairy tale. Our findings indicate that the interference of strongly represented, overlearned information in episodic memory recall is implicated in the production of confabulations in OA. This effect is particularly prominent when the to-be remembered episodic information shows strong semantic similarities with preexisting, overlearned information.

  19. Sex and age differences in mercury distribution and excretion in methylmercury-administered mice

    SciTech Connect

    Hirayama, K.; Yasutake, A.

    1986-01-01

    Sex differences in mercury distribution and excretion after single administration of methylmercury chloride (MMC, 5 mg/kg were studied in mice. A sex difference in urinary mercury excretion was found in sexually mature mice (age of 7 wk) of C57BL/6N and BALB/cA strains. Males showed higher mercury levels in urine than females, though no significant difference was found in fecal mercury levels 24 h post exposure to MMC. The higher urinary excretion rates in males accounted for significant lowering of mercury levels in the brain, liver, and blood, but not in the kidney, which showed higher values. At 5 min, however, the sex difference was found only in the kidney, showing higher levels in males. Changes in mercury distribution with time were studied in C57BL/6N mice. The brain mercury increased in both sexes up to 3 d, and decreased only in males on d 5. Liver and blood mercury decreased with time in both sexes, and these were constantly higher in females than in males. Renal mercury in males decreased to similar levels to females on d 3. The sex differences at various ages were studied with C57BL/6N mice 24 h after dosing. Two-week-old mice did not show significant sex differences in the mercury distribution and excretion, and their urinary mercury levels were much lower as compared to the older mice. Urinary mercury excretion in both sexes increased at 4 wk of age and then decreased at 45 wk of age. At 4, 7, 10, and 45 wk of age, males showed higher urinary mercury levels than females. From these findings, it has been suggested that urinary mercury excretion may be related to sex hormones, especially androgens.

  20. Computer Simulation of Random Packings for Self-Similar Particle Size Distributions in Soil and Granular Materials: Porosity and Pore Size Distribution

    NASA Astrophysics Data System (ADS)

    Martín, Miguel Angel; Muñoz, Francisco J.; Reyes, Miguel; Taguas, F. Javier

    2014-09-01

    A 2D computer simulation method of random packings is applied to sets of particles generated by a self-similar uniparametric model for particle size distributions (PSDs) in granular media. The parameter p which controls the model is the proportion of mass of particles corresponding to the left half of the normalized size interval [0,1]. First the influence on the total porosity of the parameter p is analyzed and interpreted. It is shown that such parameter, and the fractal exponent of the associated power scaling, are efficient packing parameters, but this last one is not in the way predicted in a former published work addressing an analogous research in artificial granular materials. The total porosity reaches the minimum value for p = 0.6. Limited information on the pore size distribution is obtained from the packing simulations and by means of morphological analysis methods. Results show that the range of pore sizes increases for decreasing values of p showing also different shape in the volume pore size distribution. Further research including simulations with a greater number of particles and image resolution are required to obtain finer results on the hierarchical structure of pore space.

  1. Mean age distribution of inorganic soil-nitrogen

    NASA Astrophysics Data System (ADS)

    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.

  2. Clusters and cycles in the cosmic ray age distributions of meteorites

    NASA Technical Reports Server (NTRS)

    Woodard, M. F.; Marti, K.

    1985-01-01

    Statistically significant clusters in the cosmic ray exposure age distributions of some groups of iron and stone meteorites were observed, suggesting epochs of enhanced collision and breakups. Fourier analyses of the age distributions of chondrites reveal no significant periods, nor does the same analysis when applied to iron meteorite clusters.

  3. Spatial distribution of the human enamel fracture toughness with aging.

    PubMed

    Zheng, Qinghua; Xu, Haiping; Song, Fan; Zhang, Lan; Zhou, Xuedong; Shao, Yingfeng; Huang, Dingming

    2013-10-01

    A better understanding of the fracture toughness (KIC) of human enamel and the changes induced by aging is important for the clinical treatment of teeth cracks and fractures. We conducted microindentation tests and chemical content measurements on molar teeth from "young" (18 ≤ age ≤ 25) and "old" (55 ≤ age) patients. The KIC and the mineral contents (calcium and phosphorus) in the outer, the middle, and the inner enamel layers within the cuspal and the intercuspal regions of the crown were measured through the Vickers toughness test and Energy Dispersive X-Ray Spectroscopy (EDS), respectively. The elastic modulus used for the KIC calculation was measured through atomic force microscope (AFM)-based nanoindentation tests. In the outer enamel layer, two direction-specific values of the KIC were calculated separately (direction I, crack running parallel to the occlusal surface; direction II, perpendicular to direction I). The mean KIC of the outer enamel layer was lower than that of the internal layers (p<0.05). No other region-related differences in the mechanical properties were found in both groups. In the outer enamel layer, old enamel has a lower KIC, II and higher mineral contents than young enamel (p<0.05). The enamel surface becomes more prone to cracks with aging partly due to the reduction in the interprismatic organic matrix observed with the maturation of enamel.

  4. Same-Age Unrelated Siblings: A Unique Test of Within-Family Environmental Influences on IQ Similarity.

    ERIC Educational Resources Information Center

    Segal, Nancy L.

    1997-01-01

    Pairs of genetically unrelated children reared as same-age siblings offer a design for investigating genetic and environmental influences on behavior. Results with 21 pairs support an explanatory model of intelligence that includes genetic factors. Shared environment appeared to have a very small effect on intellectual development. (SLD)

  5. Further Evidence on the Relation Between Age of Separation and Similarity in IQ Among Pairs of Separated Identical Twins.

    ERIC Educational Resources Information Center

    Vandenberg, Steven G.; Johnson, Ronald C.

    Ronald C. Johnson argued that if early environmental stimulation or deprivation has a significant effect on intellectual ability, then individuals who are genetically identical and who are exposed to a common early environment should resemble one another more closely in IQ than similar individuals who have not shared a common environment. Johnson…

  6. Child-Child Similarity on Attachment and Temperament as Predictors of Positive Interaction during Acquaintanceship at Age 3

    ERIC Educational Resources Information Center

    McElwain, Nancy L.; Ogolsky, Brian G.; Engle, Jennifer M.; Holland, Ashley S.; Mitchell, Elissa Thomann

    2016-01-01

    Child-child similarity on attachment and temperament were examined, in turn, as predictors of interaction quality between previously unacquainted children. At 33 months, child-mother attachment security was assessed, and parents reported on child temperament. At 39 months, 114 children were randomly paired into 57 same-sex dyads and observed…

  7. BOUNDARY-LAYER SIMILAR SOLUTIONS FOR EQUILIBRIUM DISSOCIATED AIR AND APPLICATION TO THE CALCULATION OF LAMINAR HEATTRANSFER DISTRIBUTION ON BLUNT BODIES IN HIGH-SPEED FLOW

    NASA Technical Reports Server (NTRS)

    Beckwith, I. E.; Cohen, N. B.

    1963-01-01

    Flat plate and stagnation flow heat transfer coefficients, similarity solutions of the laminar boundary layer for air in dissociation equilibrium and calculation of laminar heat-transfer distribution on blunt three-dimensional bodies in high speed flow

  8. Incidence, age distribution and complications of gonorrhoea in Sweden*

    PubMed Central

    Gisslén, H.; Hellgren, L.; Starck, V.

    1961-01-01

    The incidence of gonorrhoea in Sweden has shown a tendency to increase in recent years, particularly in the age-groups 15-19 and 20-24 years. However, an extrapolation of the annual incidence curve to 1970 for the 15-19-year age-group suggests that some deceleration in that increase may be expected. Study of gonococcal complications seen at Göteborg hospitals during the period 1950-59 indicates that the frequency of gonococcal salpingitis is higher than had previously been reported; this is attributed to the inclusion in the material studied of patients from departments other than those exclusively concerned with the venereal diseases. The authors conclude that, in view of the high frequency of gonorrhoea in the young and of gonococcal complications, gonorrhoea in Sweden cannot be considered an unimportant public health problem. PMID:13705767

  9. Child-child similarity on attachment and temperament as predictors of positive interaction during acquaintanceship at age 3.

    PubMed

    McElwain, Nancy L; Ogolsky, Brian G; Engle, Jennifer M; Holland, Ashley S; Mitchell, Elissa Thomann

    2016-09-01

    Child-child similarity on attachment and temperament were examined, in turn, as predictors of interaction quality between previously unacquainted children. At 33 months, child-mother attachment security was assessed, and parents reported on child temperament. At 39 months, 114 children were randomly paired into 57 same-sex dyads and observed during 3 laboratory visits over a 1-month period. Positive interaction (composed of ratings of dyadic coordination, social play complexity, and shared positive affect) was assessed from recordings of play sessions at each visit. Multilevel models revealed that child-child similarity on (a) attachment security predicted more rapid increases in positive interaction across the 3 visits for dyads averaging high security, (b) temperamental pleasure predicted more positive interaction, on average, for dyads averaging moderate to high pleasure, and (c) temperamental anger and fearfulness yielded equivocal results. Developmental and methodological implications of investigating child-child similarity on attachment and temperament as a window into the acquaintanceship process among young children are considered. (PsycINFO Database Record PMID:27570981

  10. Role of body fat distribution in the decline in insulin sensitivity and glucose tolerance with age.

    PubMed

    Coon, P J; Rogus, E M; Drinkwater, D; Muller, D C; Goldberg, A P

    1992-10-01

    The relationships of body composition and physical fitness [maximal aerobic capacity (VO2max)] to the decline in insulin sensitivity with age were examined in healthy older (47-73 yr; n = 36) and young (19-36 yr; n = 13) men. In 18 older men with normal glucose tolerance (OGTT), glucose disposal rates (M) during hyperinsulinemic euglycemic clamps correlated negatively with the waist to hip ratio (WHR; r = -0.77; P < .001) and percent body fat (r = -0.46; P < 0.05) and positively with VO2max (r = 0.54; P < 0.05), but not with age. Similar relationships existed in the 36 older men with a spectrum of OGTT responses; however, only WHR was independently related to M (r2 = 0.32; P < 0.01). In the older men with normal OGTT, M (mean +/- SEM, 7.88 +/- 0.43 mg/kg fat-free mass.min) was not different from that in the young men (8.56 +/- 0.47; P = NS). Furthermore, in older and young men with normal OGTT matched for WHR, percent fat, or VO2max, glucose disposal was comparable at sequential 15-min intervals during the clamp and in its relationship to insulin concentrations at the tissue level (multicompartmental analysis). In contrast, despite higher steady state plasma insulin levels during the clamp, M was significantly lower in the older men with a higher WHR, greater percent fat, lower VO2max, or impaired OGTT. Thus, in healthy older men up to the age of 73 yr, insulin sensitivity and glucose tolerance are affected primarily by the regional body fat distribution, not age, obesity, or VO2max.

  11. Mathematical results new and revisited on the distribution of groundwater age

    NASA Astrophysics Data System (ADS)

    Ginn, T. R.; Massoudieh, A.; Foglia, L.

    2009-12-01

    The equation governing the distribution of groundwater age under transient, 3D flow conditions is analyzed under several simplifying cases to illustrate some relations among groundwater age equations and some results about steady-state and transient age distributions. First linkages are made among the various groundwater age equations recently published, showing them all to be different simplifications of the same equation. The most basic analysis in 1D shows that groundwater age is at lease inverse-Gaussian distributed. More generally, steady state age moments, when they exist, are given by breakthrough curve moments and this allows us to use the temporal moment results from the solute transport literature as steady state age moments. In particular, age moment equations with arbitrary diffusive mass transfer (two-domain, radial microscopic, powerlaw) at steady state are already available as the temporal flux moment equations for solute transport under analogous boundary conditions. Lastly transient simulations of age in 1D are calculated to illustrate several aspects of the evolution of groundwater age distributions in time in the presences of multidomain diffusive transport.

  12. Similar immunogenicity of measles-mumps-rubella (MMR) vaccine administrated at 8 months versus 12 months age in children.

    PubMed

    He, Hanqing; Chen, Enfu; Chen, Haiping; Wang, Zhifang; Li, Qian; Yan, Rui; Guo, Jing; Zhou, Yang; Pan, Jinren; Xie, Shuyun

    2014-06-30

    Two doses of measles-mumps-rubella (MMR) strategy has been recommended by World Health Organization and is also widely adopted in many countries. In order to provide the evidence for perfecting the immunization strategy of MMR, this study evaluated the safety and immunogenicity of MMR with different two-dose schedule in infants. 280 participants were enrolled and randomly allocated to Group 1 (first dose at 8 months) or Group 2 (first dose at 12 months), and both groups administered the second dose at 10 months later. Solicited local and general symptoms after each vaccination with MMR were mild and infrequent in all participants of two groups. After administration of the first dose of MMR, seropositive rates were 100% in both groups for measles, 89.3% in Group 1 and 87.1% in Group 2 for mumps (P=0.578), 92.0% in Group 1 and 92.9% in Group 2 (P=0.393). The seropositive rates of mumps decreased significantly (from >86% to <65%) both in two groups (P<0.001) 10 months after the first dose of MMR, but no significant change was found in measles and rubella. All children get the positive titer for three vaccines in two groups after given the second dose MMR, higher seroconversion rate was found for mumps both in two groups (71.7% vs 77.2%, P=0.370). In conclusion, this study indicated that the MMR was well tolerated and immunogenic against measles, mumps and rubella with schedule of first dose both at 8 months and 12 months age. Our findings strongly supported that two doses of MMR can be introduced by replacing the first dose of MR in current EPI with MMR at 8 months age and the second dose at 18 months in China.

  13. Correlation of age with distribution of periodontitis-related bacteria in Japanese dogs.

    PubMed

    Hirai, Norihiko; Shirai, Mitsuyuki; Kato, Yukio; Murakami, Masaru; Nomura, Ryota; Yamasaki, Yoshie; Takahashi, Soraaki; Kondo, Chihiro; Matsumoto-Nakano, Michiyo; Nakano, Kazuhiko; Asai, Fumitoshi

    2013-07-31

    We analyzed the distribution of 11 periodontitis-related bacterial species in dental plaque collected from 176 Japanese dogs divided into young (less than 2 years of age), middle-aged (2-7 years of age) and elderly (more than 8 years of age) groups using a polymerase chain reaction method. Clinical examination revealed that no dogs in the young group were affected by periodontitis, whereas the rates for gingivitis and periodontitis were high in the middle-aged and elderly groups. In addition, the total numbers of bacterial species in the middle-aged and elderly groups were significantly greater than in the young group. Our findings suggest that age is an important factor associated with the distribution of periodontitis-related bacteria and periodontal conditions in dogs.

  14. Martian channels and valleys: Their characteristics, distribution, and age

    USGS Publications Warehouse

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

    1981-01-01

    All Martian channels and valleys visible at a resolution of 125 to 300 meters between 65??N and 65??S were mapped at a scale of 1:5,000,000 and the maps then digitized. Correlations of valley presence with other surface features show that almost all valleys are in the old cratered terrain. preferentially in areas of low albedo, low violet/red ratios, and high elevation. The networks are open, the individual drainage basins are small relative to Earth, and large distances separate the basins, features which all suggest an immature drainage system. The simplest explanation of the correlations and the restriction of valley networks to old terrain is that the channels themselves are old, and that the climatic conditions necessary for their formation did not prevail for long after the decline in the cratering rate around 3.9 billion years ago. Two types of outflow channel are distinguished: unconfined, in which broad swaths of terrain are scoured, and confined, in which flow is restricted to discrete channels. The outflow channels have a wide range of ages and may form under present climatic conditions. Fretted channels are largely restrited to two latitude belts centered on 40??N and 45??S, where relatively rapid erosion along escarpments results from mass wasting. They probably form by enlargement of preexisting channels by escarpment retreat. ?? 1981.

  15. Older age is associated with greater central aortic blood pressure following the exercise stress test in subjects with similar brachial systolic blood pressure.

    PubMed

    Kobayashi, Masatake; Oshima, Kazutaka; Iwasaki, Yoichi; Kumai, Yuto; Avolio, Alberto; Yamashina, Akira; Takazawa, Kenji

    2016-08-01

    Brachial systolic pressure (BSP) is often monitored during exercise by the stress test; however, central systolic pressure (CSP) is thought to be a more direct measure of cardiovascular events. Although some studies reported that exercise and aging may play roles in changes of both BSP and CSP, the relationship between BSP and CSP with age following the exercise stress test remains unclear. The aim of this study was to evaluate the effect of age on the relationship between BSP and CSP measured after exercise. Ninety-six subjects underwent the diagnostic treadmill exercise stress test, and we retrospectively divided them into the following 3 groups by age: the younger age group (43 ± 4 years), middle age group (58 ± 4 years), and older age group (70 ± 4 years). Subjects exercised according to the Bruce protocol, to achieve 85 % of their age-predicted maximum heart rate or until the appearance of exercise-associated symptoms. BSP, CSP, and pulse rate (PR) were measured using a HEM-9000AI (Omron Healthcare, Japan) at rest and after exercise. BSP, CSP, and PR at rest were not significantly different among the 3 groups (p = 0.92, 0.21, and 0.99, respectively). BSP and PR immediately after exercise were not significantly different among the groups (p = 0.70 and 0.38, respectively). However, CSP immediately after exercise was 144 ± 18 mmHg (younger age), 149 ± 17 mmHg (middle age), and 158 ± 19 mmHg (older age). CSP in the older age group was significantly higher than that in the younger age group (p < 0.01). Despite similar BSPs in all age groups after exercise, CSP was higher in the older age group. Therefore, older subjects have a higher CSP after exercise, which is not readily assessed by conventional measurements of BSP.

  16. Paleoclimate signals and age distributions from 41 public water works in the Netherlands

    NASA Astrophysics Data System (ADS)

    Broers, Hans Peter; de Weert, Jasperien; Sueltenfuss, Juergen; Aeschbach-Hertig, Werner; Vonhof, Hubert; Casteleijns, Jeroen

    2015-04-01

    Knowing the age distribution of water abstracted from public water supply wells is of prime importance to ensure customer trust and to underpin predictions of water quality evolution in time. Especially, age distributions enable the assessment of the vulnerability of well fields, both in relation to surface sources of contamination as in relation to subsurface sources, such as possibly related to shale gas extraction. We sampled the raw water of 41 large public supply well fields which represents a mixture of groundwaters and used the a discrete travel time distribution model (DTTDM, Visser et al. 2013, WRR) in order to quantify the age distribution of the mixture. Measurements included major ion chemistry, 3H, 3He, 4He, 18O, 2H, 14C, 13CDIC and 13CCH4 and the full range of noble gases. The heavier noble gases enable the calculation of the Noble Gas Temperature (NGT) which characterizes the temperature of past recharge conditions. The 14C apparent age of each mixture was derived correcting for dead carbon sources and included carbonate dissolution and methanogenesis as the defining processes. The DTTDM used the 3H and 4He concentrations, the 14C apparent age and the NGT as the four distinctive tracers to estimate the age distributions. The use of 18O was less effective because the processes that led to more enriched values are too uncertain . Especially 4He and NGT provide extra information on the older part of the age distributions and showed that the 14C apparent ages are often the result of mixing of waters ranging between 2.000 and 35.000 years old, instead of being discrete ages with a limited .variance as sometimes assumed. The results show a large range of age distributions, comprising vulnerable well fields with >60% young water (< 100 yrs) and well-protected well fields with >85% very old groundwater (> 25 kyrs) and all forms of TTD's in between. The age distributions are well in correspondence with the hydrogeological setting of the well fields; all well

  17. Paleoclimate Signals and Age Distributions from 41 Public Water Works in the Netherlands

    NASA Astrophysics Data System (ADS)

    Broers, H. P.; Weert, J. D.; Sültenfuß, J.; Aeschbach, W.; Vonhof, H.; Casteleijns, J.

    2015-12-01

    Knowing the age distribution of water abstracted from public water supply wells is of prime importance to ensure customer trust and to underpin predictions of water quality evolution in time. Especially, age distributions enable the assessment of the vulnerability of well fields, both in relation to surface sources of contamination as in relation to subsurface sources, such as possibly related to shale gas extraction. We sampled the raw water of 41 large public supply well fields which represents a mixture of groundwaters and used the a discrete travel time distribution model (DTTDM, Visser et al. 2013, WRR) in order to quantify the age distribution of the mixture. Measurements included major ion chemistry, 3H, 3He, 4He, 18O, 2H, 14C, 13CDIC and 13CCH4 and the full range of noble gases. The heavier noble gases enable the calculation of the Noble Gas Temperature (NGT) which characterizes the temperature of past recharge conditions. The 14C apparent age of each mixture was derived correcting for dead carbon sources. The DTTDM used the 3H and 4He concentrations, the 14C apparent age and the NGT as the four distinctive tracers to estimate the age distributions. Especially 4He and NGT provide extra information on the older part of the age distributions and showed that the 14C apparent ages are often the result of mixing of waters ranging between 2.000 and 35.000 years old, instead of being discrete ages with a limited .variance as sometimes assumed.The results show a large range of age distributions, comprising vulnerable well fields with >60% young water (< 100 yrs) and well-protected well fields with >85% very old groundwater (> 25 kyrs) and all forms of TTD's in between. The age distributions are well in correspondence with the hydrogeological setting of the well fields; all well fields with an age distribution skewed towards older ages are in the Roer Valley Graben structure, where fluvial and marine aquitards provide protection from recent recharge. Especially

  18. Comparison of particle-tracking and lumped-parameter age-distribution models for evaluating vulnerability of production wells to contamination

    USGS Publications Warehouse

    Eberts, S.M.; Böhlke, J.K.; Kauffman, L.J.; Jurgens, B.C.

    2012-01-01

    Environmental age tracers have been used in various ways to help assess vulnerability of drinking-water production wells to contamination. The most appropriate approach will depend on the information that is available and that which is desired. To understand how the well will respond to changing nonpoint-source contaminant inputs at the water table, some representation of the distribution of groundwater ages in the well is needed. Such information for production wells is sparse and difficult to obtain, especially in areas lacking detailed field studies. In this study, age distributions derived from detailed groundwater-flow models with advective particle tracking were compared with those generated from lumped-parameter models to examine conditions in which estimates from simpler, less resource-intensive lumped-parameter models could be used in place of estimates from particle-tracking models. In each of four contrasting hydrogeologic settings in the USA, particle-tracking and lumped-parameter models yielded roughly similar age distributions and largely indistinguishable contaminant trends when based on similar conceptual models and calibrated to similar tracer data. Although model calibrations and predictions were variably affected by tracer limitations and conceptual ambiguities, results illustrated the importance of full age distributions, rather than apparent tracer ages or model mean ages, for trend analysis and forecasting.

  19. Sex and age distribution in transport-related injuries in Tehran.

    PubMed

    Roudsari, Bahman Sayyar; Sharzei, Kaveh; Zargar, Moosa

    2004-05-01

    Intercountry or regional differences in patterns of injury by the road user type have significant implication for prevention policies. In order to have an estimate from the existing conditions of transport-related injuries (TRIs) and especially to evaluate sex and age distribution of traffic accident victims, we analyzed information of 8426 hospitalized trauma patients during 13 months of data gathering process. Forty-five percent of the injuries were related to car accidents and men/women ratio in these patients was 4.2/1. The highest men/women ratio was (16/1) for motorcyclists, while the lowest ratio (1/1), was for rear seat car passengers. Mean (+/-S.D.) age of the patients was 31 (+/-18), and men were nearly 2 years younger than women (33 versus 31). Sixty-seven percent of the females' and 44% of the males' injuries were related to pedestrian crashes. Motorcycle-related injuries in men and car passenger related injuries in women were the second most common type of crash (42 and 22%, respectively). The use of protective devices in our population was worrisome. In only 6% of the male motorcyclists helmet use was reported, and 3% of the male car occupants had used seatbelts at the time of the accident. The condition in the female population was much worse and no use of the protective devices was reported in this group of the patients. Crude mortality rate in men was nearly two times that of women (6.2% versus 3.8%). After adjustment for age, injury severity score (ISS) and category of the road users, men and women had similar mortality rate. PMID:15003584

  20. EFFECTS OF MIXING AND AGING ON WATER QUALITY IN DISTRIBUTION SYSTEM STORAGE FACILITIES

    EPA Science Inventory

    Aging of water in distribution system storage facilities can lead to deterioration of the water quality due to loss of disinfectant residual and bacterial regrowth. Facilities should be operated to insure that the age of the water is not excessive taking into account the quality...

  1. Using groundwater age distributions to estimate the effective parameters of Fickian and non-Fickian models of solute transport

    PubMed Central

    Engdahl, Nicholas B.; Ginn, Timothy R.; Fogg, Graham E.

    2015-01-01

    Groundwater age distributions are used to estimate the parameters of Fickian, and non-Fickian, effective models of solute transport. Based on the similarities between the transport and age equations, we develop a deconvolution based approach that describes transport between two monitoring wells. We show that the proposed method gives exact estimates of the travel time distribution between two wells when the domain is stationary and that the method still provides useful information on transport when the domain is non-stationary. The method is demonstrated using idealized uniform and layered 2-D aquifers. Homogeneous transport is determined exactly and non-Fickian transport in a layered aquifer was also approximated very well, even though this example problem is shown to be scale-dependent. This work introduces a method that addresses a significant limitation of tracer tests and non-Fickian transport modeling which is the difficulty in determining the effective parameters of the transport model. PMID:25821342

  2. Creating Composite Age Groups to Smooth Percentile Rank Distributions of Small Samples

    ERIC Educational Resources Information Center

    Lopez, Francesca; Olson, Amy; Bansal, Naveen

    2011-01-01

    Individually administered tests are often normed on small samples, a process that may result in irregularities within and across various age or grade distributions. Test users often smooth distributions guided by Thurstone assumptions (normality and linearity) to result in norms that adhere to assumptions made about how the data should look. Test…

  3. Similar patterns of clonally expanded somatic mtDNA mutations in the colon of heterozygous mtDNA mutator mice and ageing humans.

    PubMed

    Baines, Holly L; Stewart, James B; Stamp, Craig; Zupanic, Anze; Kirkwood, Thomas B L; Larsson, Nils-Göran; Turnbull, Douglass M; Greaves, Laura C

    2014-07-01

    Clonally expanded mitochondrial DNA (mtDNA) mutations resulting in focal respiratory chain deficiency in individual cells are proposed to contribute to the ageing of human tissues that depend on adult stem cells for self-renewal; however, the consequences of these mutations remain unclear. A good animal model is required to investigate this further; but it is unknown whether mechanisms for clonal expansion of mtDNA mutations, and the mutational spectra, are similar between species. Here we show that mice, heterozygous for a mutation disrupting the proof-reading activity of mtDNA polymerase (PolgA(+/mut)) resulting in an increased mtDNA mutation rate, accumulate clonally expanded mtDNA point mutations in their colonic crypts with age. This results in focal respiratory chain deficiency, and by 81 weeks of age these animals exhibit a similar level and pattern of respiratory chain deficiency to 70-year-old human subjects. Furthermore, like in humans, the mtDNA mutation spectrum appears random and there is an absence of selective constraints. Computer simulations show that a random genetic drift model of mtDNA clonal expansion can accurately model the data from the colonic crypts of wild-type, PolgA(+/mut) animals, and humans, providing evidence for a similar mechanism for clonal expansion of mtDNA point mutations between these mice and humans.

  4. Similar Distributions of Dupuytren's Contracture and Y-Chromosome Haplogroup I Among Modern Europeans Suggest Simultaneous Spreading of These Traits Some 40 to 10 KYA.

    PubMed

    Kurbel, Sven; Samarzija, Zdenko

    2016-04-01

    A proposition is made that when two independent traits show similar regional patterns of incidence among modern European regions, a plausible expectation is that these two, otherwise unrelated traits, have simultaneously been spread by migration of our ancestors. As a potential example for the proposed concept, distribution of patients with Dupuytren's contracture is here compared with the reported European distribution of Y-Chromosome Haplogroup I, a genetic marker linked to the last glaciation period. PMID:27301240

  5. Past and present seafloor age distributions and the temporal evolution of plate tectonic heat transport

    NASA Astrophysics Data System (ADS)

    Becker, Thorsten W.; Conrad, Clinton P.; Buffett, Bruce; Müller, R. Dietmar

    2009-02-01

    Variations in Earth's rates of seafloor generation and recycling have far-reaching consequences for sea level, ocean chemistry, and climate. However, there is little agreement on the correct parameterization for the time-dependent evolution of plate motions. A strong constraint is given by seafloor age distributions, which are affected by variations in average spreading rate, ridge length, and the age distribution of seafloor being removed by subduction. Using a simplified evolution model, we explore which physical parameterizations of these quantities are compatible with broad trends in the area per seafloor age statistics for the present-day and back to 140 Ma from paleo-age reconstructions. We show that a probability of subduction based on plate buoyancy (slab-pull, or "sqrt(age)") and a time-varying spreading rate fits the observed age distributions as well as, or better than, a subduction probability consistent with an unvarying "triangular" age distribution and age-independent destruction of ocean floor. Instead, we interpret the present near-triangular distribution of ages as a snapshot of a transient state of the evolving oceanic plate system. Current seafloor ages still contain hints of a ˜ 60 Myr periodicity in seafloor production, and using paleoages, we find that a ˜ 250 Myr period variation is consistent with geologically-based reconstructions of production rate variations. These long-period variations also imply a decrease of oceanic heat flow by ˜ - 0.25%/Ma during the last 140 Ma, caused by a 25-50% decrease in the rate of seafloor production. Our study offers an improved understanding of the non-uniformitarian evolution of plate tectonics and the interplay between continental cycles and the self-organization of the oceanic plates.

  6. [Maternal mortality in Spain, 1980-1992. Relationship with birth distributions according to the mother's age].

    PubMed

    Valero Juan, L F; Sáenz González, M C

    1997-11-01

    The maternal mortality evolution in Spain during the 1980-1992 period is reported. The influence of birth distribution according to maternal age is analyzed. The information was gathered from vital statistics published by Instituto Nacional de Estadística. The mortality rates have stabilized since 1985 (4.8 per 10(5) for 1992) associated with the increase in the proportion of births in women aged > or = 30 years (40.6% for 1992). Birth distributions according to maternal age account for 13.1% of the deaths observed. The predictions point to an increase in maternal mortality for the year 2000.

  7. Mortality Associated with Severe Sepsis Among Age-Similar Women with and without Pregnancy-Associated Hospitalization in Texas: A Population-Based Study

    PubMed Central

    Oud, Lavi

    2016-01-01

    Background The reported mortality among women with pregnancy-associated severe sepsis (PASS) has been considerably lower than among severely septic patients in the general population, with the difference being attributed to the younger age and lack of chronic illness among the women with PASS. However, no comparative studies were reported to date between patients with PASS and age-similar women with severe sepsis not associated with pregnancy (NPSS). Material/Methods We used the Texas Inpatient Public Use Data File to compare the crude and adjusted hospital mortality between women with severe sepsis, aged 20–34 years, with and without pregnancy-associated hospitalizations during 2001–2010, following exclusion of those with reported chronic comorbidities, as well as alcohol and drug abuse. Results Crude hospital mortality among PASS vs. NPSS hospitalizations was lower for the whole cohort (6.7% vs. 14.1% [p<0.0001]) and those with ≥3 organ failures (17.6% vs. 33.2% [p=0.0100]). Adjusted PASS mortality (odds ratio [95% CI]) was 0.57 (0.38–0.86) [p=0.0070]. Conclusions Hospital mortality was unexpectedly markedly and consistently lower among women with severe sepsis associated with pregnancy, as compared with contemporaneous, age-similar women with severe sepsis not associated with pregnancy, without reported chronic comorbidities. Further studies are warranted to examine the sources of the observed differences and to corroborate our findings. PMID:27286326

  8. Uranium distribution and 'excessive' U-He ages in iron meteoritic troilite

    NASA Technical Reports Server (NTRS)

    Fisher, D. E.

    1985-01-01

    Fission tracking techniques were used to measure the uranium distribution in meteoritic troilite and graphite. The obtained fission tracking data showed a heterogeneous distribution of tracks with a significant portion of track density present in the form of uranium clusters at least 10 microns in size. The matrix containing the clusters was also heterogeneous in composition with U concentrations of about 0.2-4.7 ppb. U/He ages could not be estimated on the basis of the heterogeneous U distributions, so previously reported estimates of U/He ages in the presolar range are probably invalid.

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

    NASA Astrophysics Data System (ADS)

    Soto-Ortiz, Luis; Brody, James P.

    2012-03-01

    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.

  10. Determination of the age distribution of sea ice from Lagrangian observations of ice motion

    SciTech Connect

    Kwok, R.; Cunningham, G.F.; Rothrock, D.A.; Stern, H.L.

    1995-03-01

    A procedure for monitoring the local age distribution of the Arctic sea ice cover is presented. The age distribution specifies the area covered by ice in different age classes. In the authors` approach, a regular array of grid points is defined initially on the first image of a long time series, and an ice tracker finds the positions of those points in all subsequent images of the series. These Lagrangian points mark the corners of a set of cells that move and deform with the ice cover. The area of each cell changes with each new image or time step. A positive change indicates that ice in a new age class was formed in the cell. A negative change is assumed to have ridged the youngest ice in the cell, reducing its area. The ice in each cell ages as it progresses through the time series. The area of multiyear ice in each cell is computed using an ice classification algorithm. Any area that is not accounted for by the young ice or multiyear ice is assigned to a category of older first-year ice. They thus have a fine age resolution in the young end of the age distribution, and coarse resolution for older ice. The age distribution of the young ice can be converted to a thickness distribution using a simple empirical relation between accumulated freezing-degree days and ice thickness, or using a more complicated thermodynamic model. They describe a general scheme for implementing this procedure for the Arctic Ocean from fall freeze-up until the onset of melt in the spring. The concept is illustrated with a time series of five ERS-1 SAR images spanning a period of 12 days. Such a scheme could be implemented with RADARSAT SAR imagery to provide basin-wide ice age and thickness information.

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

    PubMed Central

    2013-01-01

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

  12. Reinstatement of individual past events revealed by the similarity of distributed activation patterns during encoding and retrieval.

    PubMed

    Wing, Erik A; Ritchey, Maureen; Cabeza, Roberto

    2015-04-01

    Neurobiological memory models assume memory traces are stored in neocortex, with pointers in the hippocampus, and are then reactivated during retrieval, yielding the experience of remembering. Whereas most prior neuroimaging studies on reactivation have focused on the reactivation of sets or categories of items, the current study sought to identify cortical patterns pertaining to memory for individual scenes. During encoding, participants viewed pictures of scenes paired with matching labels (e.g., "barn," "tunnel"), and, during retrieval, they recalled the scenes in response to the labels and rated the quality of their visual memories. Using representational similarity analyses, we interrogated the similarity between activation patterns during encoding and retrieval both at the item level (individual scenes) and the set level (all scenes). The study yielded four main findings. First, in occipitotemporal cortex, memory success increased with encoding-retrieval similarity (ERS) at the item level but not at the set level, indicating the reactivation of individual scenes. Second, in ventrolateral pFC, memory increased with ERS for both item and set levels, indicating the recapitulation of memory processes that benefit encoding and retrieval of all scenes. Third, in retrosplenial/posterior cingulate cortex, ERS was sensitive to individual scene information irrespective of memory success, suggesting automatic activation of scene contexts. Finally, consistent with neurobiological models, hippocampal activity during encoding predicted the subsequent reactivation of individual items. These findings show the promise of studying memory with greater specificity by isolating individual mnemonic representations and determining their relationship to factors like the detail with which past events are remembered. PMID:25313659

  13. Polarization patterns of thick clouds: overcast skies have distribution of the angle of polarization similar to that of clear skies.

    PubMed

    Hegedüs, Ramón; Akesson, Susanne; Horváth, Gábor

    2007-08-01

    The distribution of polarization in the overcast sky has been practically unknown. Earlier the polarization of light from heavily overcast skies (when the Sun's disc was invisible) has been measured only sporadically in some celestial points by point-source polarimetry. What kind of patterns of the degree p and angle alpha of linear polarization of light could develop after transmission through a thick layer of ice or water clouds? To answer this question, we measured the p and alpha patterns of numerous totally overcast skies on the Arctic Ocean and in Hungary by full-sky imaging polarimetry. We present here our finding that depending on the optical thickness of the cloud layer, the pattern of alpha of light transmitted through the ice or water clouds of totally overcast skies is qualitatively the same as the alpha pattern of the clear sky. Under overcast conditions the value of alpha is determined predominantly by scattering on cloud particles themselves. Nevertheless, the degrees of linear polarization of light from overcast skies were rather low (pdistribution of the direction of polarization is a very robust pattern being qualitatively always the same under all possible sky conditions. This is of great importance for the orientation of polarization-sensitive animals based on sky polarization under conditions when the Sun is not visible.

  14. Transit times and age distributions for reservoir models represented as nonlinear non-autonomuous systems

    NASA Astrophysics Data System (ADS)

    Müller, Markus; Meztler, Holger; Glatt, Anna; Sierra, Carlos

    2016-04-01

    We present theoretical methods to compute dynamic residence and transit time distributions for non-autonomous systems of pools governed by coupled nonlinear differential equations. Although transit time and age distributions have been used to describe reservoir models for a long time, a closer look to their assumptions reveals two major restrictions of generality in previous studies. First, the systems are assumed to be in equilibrium; and second, the equations under consideration are assumed to be linear. While both these assumptions greatly ease the computation and interpretation of transit time and age distributions they are not applicable to a wide range of problems. Moreover, the transfer of previous results learned from linear systems in steady state to the more complex nonlinear non-autonomous systems that do not even need to have equilibria, can be dangerously misleading. Fortunately the topic of time dependent age and transit time distributions has received some attention recently in hydrology, we aim to compute these distributions for systems of multiple reservoirs. We will discuss how storage selection functions can augment the information represented in an ODE system describing a system of reservoirs. We will present analytical and numerical algorithms and a Monte Carlo simulator to compute solutions for system transit time and age distributions for system-wide storage selection functions including the most simple, but important case of well mixed pools.

  15. The histories of ordinary chondrite parent bodies - U, Th-He age distributions

    SciTech Connect

    Wasson, J.T.; Wang, Sichao Purple Mountain Observatory, Nanjing )

    1991-06-01

    Age patterns observed in meteorite groups reflect the different thermal or impact histories experienced by their parent bodies. To assess the number of ordinary chondrite (OC) parent bodies, rare-gas data in the Schultz and Kruse (1989) data base were used to calculate U, Th-He gas-retention ages. Most H- and LL-chondrite ages are high; about 81 percent are greater than 2.2 Ga. In contrast, most L-chondrite ages are low; about 69 percent are not greater than 2.2 Ga, and about 35 percent are not greater than 0.9 Ga. The latter fraction is substantially lower than the value of 44 percent given by Heymann (1967). The difference is attributed to the preferential inclusion of shocked L chondrites in early studies. Broad age peaks in the H and LL groups near 3.4 Ga probably reflect thermal loss during metamorphism, but in the H distribution there is a hint of minor outgassing 'events' near 1 Ga. The L/LL chondrites have chemical properties intermediate between and unresolvable from L and LL chondrites. The high ages of most L/LL chondrites are evidence against these originating on the L parent body; the L/LL age distribution is consistent with an origin on the LL parent body or on an independent body. 22 refs.

  16. The histories of ordinary chondrite parent bodies - U, Th-He age distributions

    NASA Astrophysics Data System (ADS)

    Wasson, John T.; Wang, Sichao

    1991-06-01

    Age patterns observed in meteorite groups reflect the different thermal or impact histories experienced by their parent bodies. To assess the number of ordinary chondrite (OC) parent bodies, rare-gas data in the Schultz and Kruse (1989) data base were used to calculate U, Th-He gas-retention ages. Most H- and LL-chondrite ages are high; about 81 percent are greater than 2.2 Ga. In contrast, most L-chondrite ages are low; about 69 percent are not greater than 2.2 Ga, and about 35 percent are not greater than 0.9 Ga. The latter fraction is substantially lower than the value of 44 percent given by Heymann (1967). The difference is attributed to the preferential inclusion of shocked L chondrites in early studies. Broad age peaks in the H and LL groups near 3.4 Ga probably reflect thermal loss during metamorphism, but in the H distribution there is a hint of minor outgassing "events" near 1 Ga. The L/LL chondrites have chemical properties intermediate between and unresolvable from L and LL chondrites. The high ages of most L/LL chondrites are evidence against these originating on the L parent body; the L/LL age distribution is consistent with an origin on the LL parent body or on an independent body.

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

    SciTech Connect

    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.

  18. Transient water age distributions in environmental flow systems: The time-marching Laplace transform solution technique

    NASA Astrophysics Data System (ADS)

    Cornaton, F. J.

    2012-03-01

    Environmental fluid circulations are very often characterized by analyzing the fate and behavior of natural and anthropogenic tracers. Among these tracers, age is taken as an ideal tracer which can yield interesting diagnoses, as for example the characterization of the mixing and renewal of water masses, of the fate and mixing of contaminants, or the calibration of hydrodispersive parameters used by numerical models. Such diagnoses are of great interest in atmospheric and ocean circulation sciences, as well in surface and subsurface hydrology. The temporal evolution of groundwater age and its frequency distributions can display important changes as flow regimes vary due to natural change in climate and hydrologic conditions and/or human induced pressures on the resource to satisfy the water demand. Groundwater age being nowadays frequently used to investigate reservoir properties and recharge conditions, special attention needs to be put on the way this property is characterized, would it be using isotopic methods or mathematical modeling. Steady state age frequency distributions can be modeled using standard numerical techniques since the general balance equation describing age transport under steady state flow conditions is exactly equivalent to a standard advection-dispersion equation. The time-dependent problem is however described by an extended transport operator that incorporates an additional coordinate for water age. The consequence is that numerical solutions can hardly be achieved, especially for real 3-D applications over large time periods of interest. A novel algorithm for solving the age distribution problem under time-varying flow regimes is presented and, for some specific configurations, extended to the problem of generalized component exposure time. The algorithm combines the Laplace transform technique applied to the age (or exposure time) coordinate with standard time-marching schemes. The method is validated and illustrated using analytical

  19. Past and present seafloor age distributions and the temporal evolution of plate tectonic heat transport

    NASA Astrophysics Data System (ADS)

    Becker, T. W.; Conrad, C. P.; Buffett, B.; Muller, D.; Loyd, S.; Lithgow-Bertelloni, C.; Corsetti, F.

    2008-12-01

    Variations in the rates of seafloor generation and recycling have potentially far-reaching consequences for sea level, ocean chemistry and climate. A parameterized framework to describe such variations could guide the study of non-uniformitarian plate tectonic activity, but there is little agreement on the appropriate mechanical description of the surface boundary layer. A strong constraint on the statistics of oceanic convection systems comes from the preserved seafloor age distribution, and additional inferences are possible when paleo-seafloor is modeled based on plate motion reconstructions. Based on previously reconstructed seafloor ages, we recently inferred that oceanic heat flow was larger by ~15% at 60~Ma than today. This signal is mainly caused by the smaller plates that existed previously in the Pacific basin with relatively larger ridge-proximal area of young seafloor. The associated decrease in heat flow is larger than any plausible decrease due to cooling, and therefore hint at cyclic behavior in plate tectonics. We also consider area-per-age statistics for the present-day and back to 140~Ma from new paleo-age reconstructions. Using a simplified seafloor age evolution model we explore which physical parameterizations for the average behavior of the oceanic lithosphere are compatible with broad trends in the data. In particular, we show that a subduction probability based on lithospheric buoyancy ("sqrt(age)") leads to results that are comparable to, or better than, that of the probability distribution that is required to obtain the "triangular" age distribution with age-independent destruction of ocean floor. The current, near triangular distribution of ages and the relative lull in heat flow are likely only snapshots of a transient state during the Wilson cycle. Current seafloor ages still contain hints of a ≤sssim 60~Myr period, cyclic variation of seafloor production, and using paleo-ages for 140~Ma, we find a ~ 400~Myr best-fitting variation

  20. Impact of Hydrologic Variability on Nutrient Age Distribution in Intensively Managed Landscapes

    NASA Astrophysics Data System (ADS)

    Kumar, P.; Woo, D. K.

    2014-12-01

    The distribution, concentration, and transport of nutrients in agricultural landscapes are of significant societal concern. Our interests in reactive nitrogen and the nitrogen cycle have shifted from increasing the efficiency of nitrogen delivery to target crop species to decreasing environmental damage caused by intensive agricultural practices. Enhancing the reactive nitrogen use efficiency to increase food production to meet future demand inevitably contributes to an increase in the reactive nitrogen load in the ecosystem, and damaging the environment. However, due to the complexity of the nitrogen cycle, the dynamics of nitrogen in soils and its interactions with ecohydrological processes at the watershed and regional scales are not well understood to enable adequate remedial measures. To unravel the complexity of this dynamics we have developed a model for characterizing the nitrogen age (elapsed time) distribution. The goal of our study is to develop and analyze the dynamics of nitrogen in the context of age and transit times resulting from advection, mixing, and production/destruction processes; evaluate the effects of micro-topographic variability on the nitrogen age distributions; and investigate how the temporal dynamics of the nitrogen age distribution are affected by changes in the variability of climate drivers. Our study is performed for the Upper Sangamon River Basin in the Critical Zone Observatory for Intensively Managed Landscapes (IML-CZO).

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

    EPA Science Inventory

    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...

  2. Age Dating Fluvial Sediment Storage Reservoirs to Construct Sediment Waiting Time Distributions

    NASA Astrophysics Data System (ADS)

    Skalak, K.; Pizzuto, J. E.; Benthem, A.; Karwan, D. L.; Mahan, S.

    2015-12-01

    Suspended sediment transport is an important geomorphic process that can often control the transport of nutrients and contaminants. The time a particle spends in storage remains a critical knowledge gap in understanding particle trajectories through landscapes. We dated floodplain deposits in South River, VA, using fallout radionuclides (Pb-210, Cs-137), optically stimulated luminescence (OSL), and radiocarbon dating to determine sediment ages and construct sediment waiting time distributions. We have a total of 14 age dates in two eroding banks. We combine these age dates with a well-constrained history of mercury concentrations on suspended sediment in the river from an industrial release. Ages from fallout radionuclides document sedimentation from the early 1900s to the present, and agree with the history of mercury contamination. OSL dates span approximately 200 to 17,000 years old. We performed a standard Weibull analysis of nonexceedance to construct a waiting time distribution of floodplain sediment for the South River. The mean waiting time for floodplain sediment is 2930 years, while the median is approximately 710 years. When the floodplain waiting time distribution is combined with the waiting time distribution for in-channel sediment storage (available from previous studies), the mean waiting time shifts to approximately 680 years, suggesting that quantifying sediment waiting times for both channel and floodplain storage is critical in advancing knowledge of particle trajectories through watersheds.

  3. Recent Changes in the U.S. Age at Death Distribution: Further Observations.

    ERIC Educational Resources Information Center

    Myers, George C.; Manton, Kenneth G.

    1984-01-01

    Responds to discussion (Fries, 1984) of an earlier article (Myers and Manton, 1984) presenting empirical evidence on changes in the distribution of ages at death. Further analysis of the data is presented, including life expectancy changes from 1950-1978 and comparison of data for men and women from several countries. (JAC)

  4. Age distribution curve in psychiatric admissions inversely correlates with Life Satisfaction.

    PubMed

    Le Bon, Olivier; Le Bon, Serge-Daniel

    2014-09-30

    A strong inverse correlation was found between the age-distribution curve of psychiatric admissions and the U-bend Life Satisfaction curve. It may indicate that the peak of mental disorders at midlife reflects a less satisfactory period of life or, conversely, that the mental health load burdens of Life Satisfaction.

  5. Bayesian evaluation of groundwater age distribution using radioactive tracers and anthropogenic chemicals

    NASA Astrophysics Data System (ADS)

    Massoudieh, Arash; Sharifi, Soroosh; Solomon, D. Kip

    2012-09-01

    The development of a Bayesian modeling approach for estimation of the age distribution of groundwater using radioactive isotopes and anthropogenic chemicals is described. The model considers the uncertainties associated with the measured tracer concentrations as well as the parameters affecting the concentration of tracers in the groundwater, and it provides the posterior probability densities of the parameters defining the groundwater age distribution using a Markov chain Monte Carlo method. The model also incorporates the effect of dissolution of aquifer minerals on diluting the 14C signature and the uncertainties associated with this process on the inferred age distribution parameters. Two demonstration modeling cases have been performed. First, the method was applied to simulated tracer concentrations at a discharge point of a hypothetical 2-D vertical aquifer with two recharge zones, leading to a mixed groundwater age distribution under different presumed uncertainties. When the error variance of the observed tracer concentrations is considered unknown, the method can estimate the parameters of the fitted exponential-lognormal distribution with a relatively narrow credible interval when five hypothetical samples are assumed to be collected at the discharge point. However, when a single sample is assumed, the credible intervals become wider, and credible estimations of the parameters are not obtained. Second, the method was applied to the data collected at La Selva Biological Station in Costa Rica. In this demonstration application, nine different forms of presumed groundwater age distributions have been considered, including four single forms and five mixed forms, assuming the groundwater consists of distinct young and old fractions. For the medium geometrical standard deviationδc,i = 1.41, the model estimates a young groundwater age of between 0 and 350 years, with the largest odds being given to a mean age of approximately 100 years, and a fraction of young

  6. Thermal and tectonic evolution of the central and southern Appalachians: evidence from distribution, age, and origin of granitic rocks

    SciTech Connect

    Sinha, A.K.; Guy, R.; Hund, E.; Tamburro, E.

    1985-01-01

    The distribution and resolution of thermal events and associated igneous activity can discriminate between tectonic processes that form orogenic terrains, i.e., accretion of terranes, overthrusting of terranes versus thrust stacking within terranes. Reinterpretation of regional tectonics (Higgins et al., 1984) coupled with the authors interpretation of the age, origin, and distribution of granitic rocks suggest a very different mechanism for the evolution of the central and southern Appalachian orogenic belt. The Cambro-Ordovician magmatic arc (weakly bimodal) separated from the North American Margin by a Back arc basin, was thrust over the North American plate margin during the middle Ordovician. The Avalon terrane (Little River allochthon of Higgins et al., 1984) arrived during the late Silurian - but unlike earlier models that require subduction zone related with its arrival, the authors postulate strike-slip tectonics. The gabbro-diorite-syenite association in the Charlotte belt (Macon melange of Higgins) is probably related to grabens associated with the strike-slip accretion. Rocks of similar age (Siluro-Devonian) in the present day Blue Ridge and Inner Piedmont blocks are related to decompressional melting after the Ordovician thrusting. The high pressure metamorphism and associated melting show a range in ages indicating variations in uplift rates or thickness of the crust caused by the initial overthrusting, and do not require a discrete subduction or orogenic event. The Permo-Carboniferous igneous activity, and associated uplift and thrusting with a strike-slip component are related to oblique subduction and post-subduction collision processes.

  7. Constraining age distributions of groundwater from public supply wells in diverse hydrogeological settings in Scania, Sweden

    NASA Astrophysics Data System (ADS)

    Åkesson, Maria; Suckow, Axel; Visser, Ate; Sültenfuβ, Jürgen; Laier, Troels; Purtschert, Roland; Sparrenbom, Charlotte J.

    2015-09-01

    Twenty-five public supply wells throughout the hydrogeologically diverse region of Scania, southern Sweden are subjected to environmental tracer analysis (3H-3He, 4He, CFCs, SF6 and for one well only also 85Kr and 39Ar) to study well and aquifer vulnerability and evaluate possibilities of groundwater age distribution assessment. We find CFC and SF6 concentrations well above solubility equilibrium with modern atmosphere, indicating local contamination, as well as indications of CFC degradation. The tracer-specific complications considerably constrain possibilities for sound quantitative regional groundwater age distribution assessments and demonstrate the importance of initial qualitative assessment of tracer-specific reliability, as well a need for additional, complementary tracers (e.g. 85Kr, 39Ar and potentially also 14C). Lumped parameter modelling yields credible age distribution assessments for representative wells in four type aquifers. Pollution vulnerability of the aquifer types was based on the selected LPM models and qualitative age characterisation. Most vulnerable are unconfined dual porosity and fractured bedrock aquifers, due to a large component of very young groundwater. Unconfined sedimentary aquifers are vulnerable due to young groundwater and a small pre-modern component. Less vulnerable are semi-confined sedimentary or dual-porosity aquifers, due to older age of the modern component and a larger pre-modern component. Confined aquifers appear least vulnerable, due an entirely pre-modern groundwater age distribution (recharged before 1963). Tracer complications aside, environmental tracer analyses and lumped parameter modelling aid in vulnerability assessment and protection of regional groundwater resources.

  8. Prevalence of dominant mutations in Spain: effect of changes in maternal age distribution.

    PubMed

    Martínez-Frías, M L; Herranz, I; Salvador, J; Prieto, L; Ramos-Arroyo, M A; Rodríguez-Pinilla, E; Cordero, J F

    1988-12-01

    We studied the birth prevalence of autosomal dominant mutations in Spain and estimated how a decrease in maternal age distribution may lead to reduction in dominant mutations. The data were collected by the Estudio Colaborativo Español de Malformaciones Congénitas from April, 1976, to December, 1985. Among 553,270 liveborn infants monitored during the period, 66 infants with autosomal dominant conditions were identified. These included Apert, Crouzon, Hay-Wells, Treacher-Collins, Robinow, Stickler, Adams-Oliver, and the blepharophimosis syndromes, achondroplasia, cleidocranial dysostosis, and thanatophoric dysplasia. The overall rate of autosomal dominant conditions was 1.2 per 10,000 liveborn infants. Thirteen (20%) had an affected relative, and 52 (79%) had a negative family history. One case was excluded because of insufficient family data. The rate of autosomal dominant mutations was 0.9 per 10,000 liveborn infants, or 47 per 1 million gametes. A reduction in the maternal age distribution of mothers age 35 years and older from the current 10.8% to 4.9%, as in Atlanta, Georgia, would reduce the rate of Down syndrome in Spain by 33% and through a change in parternal age distribution may lead to a reduction in dominant mutations of about 9.6%. This suggests that a public health campaign to reduce older maternal age distribution in Spain may also lead to a reduction in dominant mutations and emphasizes the potential that a direct campaign for fathers to complete their families before age 35 years may have a small, but measurable, effect in the primary prevention of dominant mutations.

  9. The Age, Mass, and Size Distributions of Star Clusters in M51

    NASA Astrophysics Data System (ADS)

    Chandar, Rupali; Whitmore, Bradley C.; Dinino, Daiana; Kennicutt, Robert C.; Chien, L.-H.; Schinnerer, Eva; Meidt, Sharon

    2016-06-01

    We present a new catalog of 3816 compact star clusters in the grand design spiral galaxy M51 based on observations taken with the Hubble Space Telescope. The age distribution of the clusters declines starting at very young ages, and can be represented by a power law, {dN}/dτ \\propto {τ }γ , with γ =-0.65+/- 0.15. No significant changes in the shape of the age distribution at different masses is observed. The mass function of the clusters younger than τ ≈ 400 {{Myr}} can also be described by a power law, {dN}/{dM}\\propto {M}β , with β ≈ \\-2.1+/- 0.2. We compare these distributions with the predictions from various cluster disruption models, and find that they are consistent with models where clusters disrupt approximately independent of their initial mass, but not with models where lower mass clusters are disrupted earlier than their higher mass counterparts. We find that the half-light radii of clusters more massive than M ≈ 3× {10}4 {M}⊙ and with ages between 100 and 400 {{Myr}} are larger by a factor of ≈3-4 than their counterparts that are younger than 107 years old, suggesting that the clusters physically expand during their early life.

  10. X-Ray induced cataract is preceded by LEC loss, and coincident with accumulation of cortical DNA, and ROS; similarities with age-related cataracts

    PubMed Central

    Zitnik, Galynn; Tsai, Ryan; Wolf, Norman

    2010-01-01

    -eyes were examined for ROS damage to DNA with antibodies specific for 8-OH-G lesions. The frequency of 8-OH-G lesions increased dramatically in lenses from old unirradiated mice over 24 months of age, and similarly in X-irradiated lenses by 9–11 months post irradiation. The accumulation of cortical nuclei was not the result of conversion or invasion by myofibroblasts as tested by antibodies to a marker for such cells, alpha smooth muscle actin. Conclusions X-irradiation damage induces a large decrease in surface LECs over a period of 3–11 months post X-irradiation of young mice. These changes are similar in extent to those seen in 24–29 months-old control mouse lenses with age-related cataracts. In 24+ month-old unirradiated mice the secondary lens fibers are not able to degrade nuclei or nuclear DNA efficiently and accumulate large numbers of cortical nuclei and nuclear fragments as well as ROS and 8-OHG lesions. X-irradiated lenses develop the same abnormalities in a more accelerated fashion. The extensive loss of LECS and accumulation of undegraded nuclei, ROS, and ROS damage may play a causal role in cataract generation in both unirradiated old mice and in previously irradiated young adult mice. PMID:20806081

  11. Hatching, dispersal, and bathymetric distribution of age-0 wild lake trout at the Gull Island Shoal complex, Lake Superior

    USGS Publications Warehouse

    Bronte, Charles R.; Selgeby, James H.; Saylor, James H.; Miller, Gerald S.; Foster, Neal R.

    1995-01-01

    We studied age-0 lake trout (Salvelinus namaycush) associated with spawning and nursery areas of the Gull Island Shoal complex in western Lake Superior. Post-emergent age-0 lake trout were captured on rocky spawning substrate with a 3-m beam trawl and at the nursery area with a bottom trawl from June to September 1990 and June to August 1991. Catch data suggested that age-0 lake trout move distances of 7–11 km to the nursery area over a 3-month period. Water currents, measured at Gull Island Shoal, may be a part of the transport mechanism. Examination of daily-growth increments on the sagittae and back-calculation from the date of capture revealed that most fish hatched between 6 June and 19 July in 1990 and between 30 April and 30 May in 1991. The duration of the hatch was 100 days in 1990 and 120 days in 1991, and the estimated incubation period is about 7 months for lake trout eggs at this site. Similar hatch-date distributions of age-0 captured on different sampling dates suggested that natural mortality was low.

  12. Reconstructing merger timelines using star cluster age distributions: the case of MCG+08-11-002

    NASA Astrophysics Data System (ADS)

    Davies, Rebecca L.; Medling, Anne M.; U, Vivian; Max, Claire E.; Sanders, David; Kewley, Lisa J.

    2016-05-01

    We present near-infrared imaging and integral field spectroscopy of the centre of the dusty luminous infrared galaxy merger MCG+08-11-002, taken using the Near InfraRed Camera 2 (NIRC2) and the OH-Suppressing InfraRed Imaging Spectrograph (OSIRIS) on Keck II. We achieve a spatial resolution of ˜25 pc in the K band, allowing us to resolve 41 star clusters in the NIRC2 images. We calculate the ages of 22/25 star clusters within the OSIRIS field using the equivalent widths of the CO 2.3 μm absorption feature and the Br γ nebular emission line. The star cluster age distribution has a clear peak at ages ≲ 20 Myr, indicative of current starburst activity associated with the final coalescence of the progenitor galaxies. There is a possible second peak at ˜65 Myr which may be a product of the previous close passage of the galaxy nuclei. We fit single and double starburst models to the star cluster age distribution and use Monte Carlo sampling combined with two-sided Kolmogorov-Smirnov tests to calculate the probability that the observed data are drawn from each of the best-fitting distributions. There is a >90 per cent chance that the data are drawn from either a single or double starburst star formation history, but stochastic sampling prevents us from distinguishing between the two scenarios. Our analysis of MCG+08-11-002 indicates that star cluster age distributions provide valuable insights into the timelines of galaxy interactions and may therefore play an important role in the future development of precise merger stage classification systems.

  13. Lycopene intake by Canadian women is variable, similar among different ages, but greater than that reported for women in other countries.

    PubMed

    Mackinnon, E S; Rao, A V; Rao, L G

    2009-08-01

    Lycopene is an antioxidant associated with a reduced risk of chronic diseases common in women such as osteoporosis and cancer; however, no official recommendation for lycopene consumption exists, and intake data from Canadian women are limited. This study was designed to generate information about average lycopene intake in Canadian women of different ages. A cross-sectional study was conducted at St. Michael's Hospital in Toronto, Ontario, Canada. One hundred one women, between the ages of 25 and 70 years, who were not on any medications, were recruited to record their diet for 7 days. Statistical analyses were performed to compare the types of lycopene-containing foods consumed, associations between intake of lycopene and macro/micronutrients, and whether participant characteristics, such as body mass index, could predict lycopene intake. Average lycopene intake was 6.14 +/- 5.35 mg/day, which is higher than reported in other countries. Intake was similar among age groups but was highly variable. Raw tomatoes were the most frequently consumed source of lycopene, while participants with the highest lycopene intake consumed more cooked/processed tomato products than those with lower intake (P < .005). Participants 25-49 years old consumed more dried/powdered tomatoes (P < .05), pizza (P < .002), and ketchup (P < .10) than 50-70 year olds. Lycopene intake could not be predicted by any participant characteristics. In older participants, lycopene intake was positively correlated with intake of calcium, niacin, and vitamins A, D, and K (P < or = .05). These findings are significant to women's health and may contribute to the establishment of nutritional and health recommendations regarding consumption of lycopene by Canadian women to prevent chronic diseases. PMID:19735184

  14. Intensively-Managed Young Children with Type 1 Diabetes Consume High-Fat, Low-Fiber Diets Similar to Age-Matched Controls

    PubMed Central

    Mehta, Sanjeev N.; Volkening, Lisa K.; Quinn, Nicolle; Laffel, Lori M.B.

    2014-01-01

    Despite significant emphasis on nutrition, older children with diabetes demonstrate poor dietary quality. We tested the hypothesis that dietary quality in young children with type 1 diabetes (T1D) would be better than age-matched children in the US population. Dietary data from children with T1D (n=67), ages 2–12 years, attending a pediatric diabetes clinic were compared to a nationally representative, age-matched sample from the National Health and Nutrition Examination Survey (NHANES, n=1691). Multiple 24-hour dietary recalls were used. Recommended intakes were based on national guidelines, and dietary quality was assessed using the Healthy Eating Index-2005 (HEI-2005). More children with T1D were overweight or obese compared to children participating in NHANES (42% vs. 30%, p=0.04). Greater proportions of children with T1D met daily recommendations for vegetables (22% vs. 13%, p=0.03), whole grains (12% vs. 5%, p=0.005), and dairy (55% vs. 36%, p=0.001) compared to NHANES children while similar proportions met daily fruit recommendations (40% vs. 33%, p=0.2). Less than one-third of all children limited total fat to recommended levels; children with T1D consumed more saturated fat than NHANES children (14% vs. 12% total energy intake, p=0.0009). Fiber intakes were very low in both groups. Compared to NHANES children, children with T1D had higher HEI-2005 scores (59.6 vs. 49.7, p=0.0006) primarily due to lower intakes of added sugars. The nutritional intake of young children with T1D remains suboptimal in the contemporary era of diabetes management. Despite focused nutrition management, young children with T1D consume high-fat, low-fiber diets comparable to youth in the general population. PMID:24916556

  15. Epidemiology of Neisseria meningitidis infections: case distribution by age and relevance of carriage.

    PubMed

    Gabutti, G; Stefanati, A; Kuhdari, P

    2015-01-01

    Notwithstanding different meningococcal serogroups have changed their distribution and their impact in different age classes over time, N. meningitidis' invasive diseases are a major public health issue worldwide, due to the related complications and severe sequelae. Nowadays, the highest rates of invasive disease are registered in children younger than 1 year of age, with a second lesser peak in adolescents and young adults (15-25 years of age). On the contrary, the prevalence of carriage is low in newborns and in school-age children, and increases during adolescence and young-adult age; then it decreases again in older age. N. meningitidis' infection prevalence has greatly decreased in Europe and North America thanks to the use of conjugate vaccines (MenC and MenACWY) as well as the incidence of invasive disease due to serogroup A in sub-saharian Africa after the introduction of MenAfriVac conjugate vaccine. The great success of conjugate vaccines is related not only to the direct protection from disease but also to the impact on carriage; this latter allows an indirect protection of unimmunized subjects. For these reasons, the implementation of immunization with the new generation vaccines in the age classes most impacted by disease and carriage (first year of life, adolescence and young adulthood) could permit to achieve an extraordinary decrease of the incidence of meningococcal disease. PMID:26788731

  16. Fast Airborne Size Distribution Measurements of an Aerosol Processes and Aging

    NASA Astrophysics Data System (ADS)

    Kapustin, V.; Clarke, A. D.; Zhou, J.; Brekhovskikh, V.; McNaughton, C. S.; Howell, S.

    2009-12-01

    During MILAGRO/INTEX experiment the Hawaii Group for Environmental Aerosol Research (HIGEAR) deployed a wide range of aerosol instrumentation aboard NSF C-130 and NASA DC-8. These were designed to provide rapid information on aerosol composition, state of mixing (internal or external), spectral optical properties (scattering and absorption), the humidity dependence of light scattering - f(RH), and the role of condensed species in changing the absorption properties of black carbon (BC) and inferred properties of organic carbon (OC). We also flew the Fast Mobility Particle Spectrometer (FMPS, TSI Inc.) to measure aerosol size distributions in a range 5.6 - 560 nm. For all our flights around Mexico City, an aerosol number concentration usually was well above the nominal FMPS sensitivity (from ~100 particles/cc @ Dp = 5.6 nm to 1 part/cc @ 560nm), providing us with reliable size distributions even at 1 sec resolution. FMPS measurements revealed small scale structure of an aerosol and allowed us to examine size distributions varying over space and time associated with mixing processes previously unresolved. These 1-Hz measurements during aircraft profiles captured variations in size distributions within shallow layers. Other dynamic processes observed included orography induced aerosol layers and evolution of the nanoparticles formed by nucleation. We put FMPS high resolution size distribution data in a context of aerosol evolution and aging, using a range of established (for MIRAGE/INTEX) chemical, aerosol and transport aging parameters.

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

    PubMed

    Büsse, Sebastian; von Grumbkow, Philipp; Hummel, Susanne; Shah, Deep Narayan; Tachamo Shah, Ram Devi; Li, Jingke; Zhang, Xueping; Yoshizawa, Kazunori; Wedmann, Sonja; Hörnschemeyer, Thomas

    2012-01-01

    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.

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

    SciTech Connect

    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.

  19. Trends in maternal age distribution and the live birth prevalence of Down's syndrome in England and Wales: 1938-2010.

    PubMed

    Wu, Jianhua; Morris, Joan K

    2013-09-01

    There have been concerns about the effects of increases in maternal age since the 1980s on the prevalence of Down's syndrome. This study examined changes in the distribution of maternal age in England and Wales from 1938 to 2010. The live birth prevalence of Down's syndrome in the absence of screening and subsequent termination was estimated using the numbers of babies born in England and Wales according to maternal age and the maternal age-related risk of a birth with Down's syndrome. The proportion of women age 35 years or older at the time of giving birth reached a peak of 20% in 1945, declined to 5.5% in 1977 and rose to 20% in 2007. In the absence of screening and subsequent termination, the estimated live birth prevalence of Down's syndrome would have mirrored these changes (2.3 per 1000 births in 1945, 1.2 per 1000 in 1976 and 2.2 per 1000 in 2007). The observed live birth prevalence (recorded by the National Down Syndrome Cytogenetic Register) was1.0 per 1000 from 1989 to 2010, due to screening and subsequent termination. In conclusion since the 1980s there has been an increase in the mean maternal age and in the expected prevalence of Down's syndrome. When put in a longer historical context the current expected live birth prevalence is similar to that in the 1940s and the observed live birth prevalence is about 54% less than expected, due to screening and subsequent termination, and has remained reasonably constant since 1989 at 1.0 per 1000 births.

  20. Spatial and temporal simulation of groundwater age distributions of a small mountainous catchment

    NASA Astrophysics Data System (ADS)

    Gundel, Anita; Weiler, Markus; Schirmer, Mario

    2013-04-01

    The spatial and temporal storage characteristics of catchments are relevant to identify the vulnerability of catchments to climate change. Areas with high mean groundwater ages imply long residence times of water particles in the aquifer and are therefore a good indicator for high storage capacity of a catchment. Groundwater age in general is strongly influenced by porosity, flow direction and flow velocity. Hence, the great challenge for moutainous catchments is the steep topography and the complex geology which has the greatest impact on the groundwater age distribution. The main purpose of this study is the simulation of the groundwater age of a well-instrumented pre-alpine catchment in time and space to identify storage characteristics. One possibility to simulate groundwater age distributions in space and time is the application of a numerical groundwater model, which takes into account complex geological structures as well as the flow and transport processes of the unsaturated and saturated zone. In our study, we used the numerical 3D-finite-element groundwater flow and transport model FEFLOW with a transient direct mean age simulation method based on a mass-weighted average age. The study catchment Rietholzbach is located in the north-east of Switzerland, for which an adequate data set of discharge, groundwater level, and isotopic composition of the groundwater and stream water exists. First of all, a steady-state groundwater flow model was developed to validate the stability and accuracy of the flow simulation and model structure. Secondly, the steady-state results provide the initial conditions for the transient flow and transport simulation of the groundwater age distribution. Residence time simulations of this model were benchmarked against the stable isotope signal δ18O of groundwater and discharge. The results show that less water is stored along the creek in the shallow aquifer (young water) whereas substantial storage capacities (old water) are

  1. Intergenerational transfers in industrialised countries: effects of age distribution and economic institutions.

    PubMed

    Ermisch, J

    1989-01-01

    In Great Britain, using mid 1980s data and assuming no productivity increase over generations thereby making the discount rate and population growth rate 0, the average ages of household consumption and production stood at 46.3 and 41.3 respectively. Further, assuming 2% annual productivity growth and discount rates, the average consumption age was 41.7 and the average production age was 38.7. Therefore, net transfers here passed from the younger to older generations. In Japan, 1985 data shows that, under the same assumptions as Great Britain, the average ages of household consumption and production stood at 50.8 and 44.3 respectively. When assuming 2% annual productivity growth and discount rates, Japan's average consumption age was 41.7 and it's average production age was 38.7. Like Great Britain, Japan's net transfers passed from the younger to older generations. Specifically, production was significantly higher than consumption in the 20-60 year old age group and the reverse occurred in the older age groups. Even though there were similar patterns between the 2 countries, the difference between the average ages of consumption and production for Japan is much larger than for Great Britain. Further, it is even greater than the United States' whose estimates correspond to Japan's and Great Britain's. Specifically, the strength of the transfer effect is higher for Japan than Great Britain or the US because of the longer life expectancy among the Japanese. In addition, due to changes in fertility and mortality, the proportion of the 15 year olds has decreased and the proportion of those or = 65 years old has increased. Therefore net transfers have shifted in favor of the older generations.

  2. Age distribution patterns of patients with conventional ductal adenocarcinoma of the pancreas. A single-institution study of 580 cases re-evaluated using current histopathological diagnostic criteria.

    PubMed

    Liszka, Łukasz; Pająk, Jacek; Mrowiec, Sławomir; Zielińska-Pająk, Ewa; Lampe, Paweł; Gołka, Dariusz

    2010-01-01

    There are a few studies concerning epidemiology of pancreatic ductal adenocarcinoma (PDAC) in the Polish population. Analysis of age distribution patterns of patients with different types of cancer may be useful for studying their specific biology. In the present study we aimed to describe age distribution patterns of 580 patients with PDAC diagnosed in one centre during a 25-year period. All the histopathological diagnoses were re-reviewed using current histopathological diagnostic criteria. Age distributions of selected subpopulations of patients (defined based on gender, potential tumour resectability and type of the surgery) were compared using mean values, medians, age frequency density plots and logarithmic plots of age-specific frequencies. The mean and median values of patients' age were 60.8 y and 61.0 y, respectively. Females were approximately 2 y older than males at the time of PDAC diagnosis. Females with non-resectable PDAC were approximately 2 y older than females with resectable tumours. Mean age values of males with non-resectable and resectable PDAC were similar. Patients treated with pancreaticoduodenectomy were approximately 2 y older than patients undergoing other types of resections. Age distribution density plots showed that some subgroups of patients studied were somewhat heterogeneous and might include several yet poorly recognized clinico-pathological entities. Logarithmic plots of age-specific frequencies showed that PDAC epidemiology is in concordance with a multistage theory of carcinogenesis. PDAC is an age-dependent cancer. Single-institutional pathology-oriented cancer epidemiological databases may add some information to population-based cancer registries.

  3. Analyzing nutrient distribution in different particle-size municipal aged refuse.

    PubMed

    Li, Guangke; Hou, Fen; Guo, Zhen; Yao, Gaoyi; Sang, Nan

    2011-11-01

    To investigate the feasibility of using aged municipal solid waste as farmland soil, it is essential to study its nutritive compositions for plant growth. Previous studies have demonstrated that the properties of different particle-size aged refuse are very different, therefore, the present study was conducted to evaluate the adequacy of three elements (N, P, K) and the fractionation of inorganic P in the aged refuse with a particle-size distribution of 900 to 300, 300 to 150, 150 to 105, 105 to 90 and 90 to 0 μm. The results indicate that (1) total quantities of N, P, K were much larger than that in the general soil and the quantities of available N, P and K were also adequate; (2) total content of P was sufficient, but the ratio of available-P to total P was not high enough; (3) with the decrease of particle size, the contents of these elements presented different trends. The results implicate that total contents of N, P and K were enough for the aged refuse being exploited as cultivated soil, and different gradation of aged refuse could be added to improve poor soils. It provides scientific evidence for utilizing different particle-size aged refuse comprehensively.

  4. Star-cluster mass and age distributions of two fields in M83 based on HST/WFC3 observations

    SciTech Connect

    Chandar, Rupali; Whitmore, Bradley C.; Calzetti, Daniela; O'Connell, Robert

    2014-05-20

    We study star clusters in two fields in the nearby spiral galaxy M83 using broadband and narrowband optical imaging taken with the Wide Field Camera 3 onboard the Hubble Space Telescope. We present results on the basis of several different catalogs of star clusters in inner and outer fields, and we conclude that different methods of selection do not strongly affect the results, particularly for clusters older than ≈10 Myr. The age distributions can be described by a power law, dN/dτ∝τ{sup γ}, with γ ≈ –0.84 ± 0.12 in the inner field, and γ ≈ –0.48 ± 0.12 in the outer field for τ ≳ 10 Myr. We bracket the difference, Δγ, between the two fields to be in the 0.18 to 0.36 range, based on estimates of the relative star-formation histories. The mass functions can also be described by a power law, dN/dM∝M {sup β}, with β ≈ –1.98 ± 0.14 and β ≈ –2.34 ± 0.26 in the inner and outer fields, respectively. We conclude that the shapes of the mass and age distributions of the clusters in the two fields are similar, as predicted by the quasi-universal model. Any differences between the two fields are at the ≈2σ-3σ (≈1σ-2σ) level for the age (mass) distributions. Therefore, any dependence of these distributions on the local environment is probably weak. We compare the shapes of the distributions with those predicted by two popular cluster disruption models. We find that both show evidence that the clusters are disrupted at a rate that is approximately independent of their mass. We compare the shapes of the distributions with those predicted by two popular cluster disruption models, and find that both show evidence that the clusters are disrupted at a rate that is approximately independent of their mass, and that observational results do not support the earlier disruption of lower-mass clusters relative to their higher-mass counterparts.

  5. Age-related changes in endothelial permeability and distribution volume of albumin in rat aorta.

    PubMed

    Belmin, J; Corman, B; Merval, R; Tedgui, A

    1993-03-01

    Age-related changes in macromolecular transport across the arterial wall were investigated in 10-, 20-, and 30-mo-old WAG/Rij rats. Animals were injected with 125I- and 131I-labeled albumin, 90 and 5 min before they were killed, respectively. The transmural distribution of relative concentration of tracers in the aortic wall was obtained using en face serial sectioning technique. The apparent endothelial permeability to albumin calculated from the distribution of 5-min 131I-labeled albumin concentrations was significantly enhanced in 20- and 30-mo-old rats compared with 10-mo-old rats. The apparent distribution volume of albumin within the media, estimated as the mean medial 125I-labeled albumin concentration, was not significantly changed in 20-mo-old rats but was significantly decreased in the 30-mo-old animals. These age-related changes in the macromolecular transport suggest that the entry of plasma macromolecules in the aged arterial wall might be enhanced, whereas the efflux through the media may be impeded, possibly contributing to their trapping in the subendothelium. PMID:8456970

  6. Competition and habitat quality influence age and sex distribution in wintering rusty blackbirds.

    PubMed

    Mettke-Hofmann, Claudia; Hamel, Paul B; Hofmann, Gerhard; Zenzal, Theodore J; Pellegrini, Anne; Malpass, Jennifer; Garfinkel, Megan; Schiff, Nathan; Greenberg, Russell

    2015-01-01

    Bird habitat quality is often inferred from species abundance measures during the breeding and non-breeding season and used for conservation management decisions. However, during the non-breeding season age and sex classes often occupy different habitats which suggest a need for more habitat-specific data. Rusty Blackbird (Euphagus carolinus) is a forested wetland specialist wintering in bottomland hardwood forests in the south-eastern U. S. and belongs to the most steeply declining songbirds in the U.S. Little information is available to support priority birds such as the Rusty Blackbird wintering in this threatened habitat. We assessed age and sex distribution and body condition of Rusty Blackbirds among the three major habitats used by this species in the Lower Mississippi Alluvial Valley and also measured food availability. Overall, pecan groves had the highest biomass mainly driven by the amount of nuts. Invertebrate biomass was highest in forests but contributed only a small percentage to overall biomass. Age and sex classes were unevenly distributed among habitats with adult males primarily occupying pecan groves containing the highest nut biomass, females being found in forests which had the lowest nut biomass and young males primarily staying in forest fragments along creeks which had intermediate nut biomass. Males were in better body condition than females and were in slightly better condition in pecan groves. The results suggest that adult males occupy the highest quality habitat and may competitively exclude the other age and sex classes.

  7. Competition and Habitat Quality Influence Age and Sex Distribution in Wintering Rusty Blackbirds

    PubMed Central

    Mettke-Hofmann, Claudia; Hamel, Paul B.; Hofmann, Gerhard; Zenzal Jr., Theodore J.; Pellegrini, Anne; Malpass, Jennifer; Garfinkel, Megan; Schiff, Nathan

    2015-01-01

    Bird habitat quality is often inferred from species abundance measures during the breeding and non-breeding season and used for conservation management decisions. However, during the non-breeding season age and sex classes often occupy different habitats which suggest a need for more habitat-specific data. Rusty Blackbird (Euphagus carolinus) is a forested wetland specialist wintering in bottomland hardwood forests in the south-eastern U. S. and belongs to the most steeply declining songbirds in the U.S. Little information is available to support priority birds such as the Rusty Blackbird wintering in this threatened habitat. We assessed age and sex distribution and body condition of Rusty Blackbirds among the three major habitats used by this species in the Lower Mississippi Alluvial Valley and also measured food availability. Overall, pecan groves had the highest biomass mainly driven by the amount of nuts. Invertebrate biomass was highest in forests but contributed only a small percentage to overall biomass. Age and sex classes were unevenly distributed among habitats with adult males primarily occupying pecan groves containing the highest nut biomass, females being found in forests which had the lowest nut biomass and young males primarily staying in forest fragments along creeks which had intermediate nut biomass. Males were in better body condition than females and were in slightly better condition in pecan groves. The results suggest that adult males occupy the highest quality habitat and may competitively exclude the other age and sex classes. PMID:25946335

  8. Competition and habitat quality influence age and sex distribution in wintering rusty blackbirds.

    PubMed

    Mettke-Hofmann, Claudia; Hamel, Paul B; Hofmann, Gerhard; Zenzal, Theodore J; Pellegrini, Anne; Malpass, Jennifer; Garfinkel, Megan; Schiff, Nathan; Greenberg, Russell

    2015-01-01

    Bird habitat quality is often inferred from species abundance measures during the breeding and non-breeding season and used for conservation management decisions. However, during the non-breeding season age and sex classes often occupy different habitats which suggest a need for more habitat-specific data. Rusty Blackbird (Euphagus carolinus) is a forested wetland specialist wintering in bottomland hardwood forests in the south-eastern U. S. and belongs to the most steeply declining songbirds in the U.S. Little information is available to support priority birds such as the Rusty Blackbird wintering in this threatened habitat. We assessed age and sex distribution and body condition of Rusty Blackbirds among the three major habitats used by this species in the Lower Mississippi Alluvial Valley and also measured food availability. Overall, pecan groves had the highest biomass mainly driven by the amount of nuts. Invertebrate biomass was highest in forests but contributed only a small percentage to overall biomass. Age and sex classes were unevenly distributed among habitats with adult males primarily occupying pecan groves containing the highest nut biomass, females being found in forests which had the lowest nut biomass and young males primarily staying in forest fragments along creeks which had intermediate nut biomass. Males were in better body condition than females and were in slightly better condition in pecan groves. The results suggest that adult males occupy the highest quality habitat and may competitively exclude the other age and sex classes. PMID:25946335

  9. Similarity of the CDC and WHO weight-for-length growth charts in predicting risk of obesity at age 5 years.

    PubMed

    Rifas-Shiman, Sheryl L; Gillman, Matthew W; Oken, Emily; Kleinman, Ken; Taveras, Elsie M

    2012-06-01

    The World Health Organization (WHO) 2006 weight-for-length (WFL) or BMI growth charts are now recommended as the new standard for children under 24 months. The objective of this study was to examine associations of ever being overweight during 1-24 months, based on the older Centers for Disease Control and Prevention (CDC) and WHO cutpoints, with risk of obesity at age 5 years. From well-child visits to a Massachusetts multi-site group practice during 1980-2008, we studied 15,488 children with length/height and weight measurements at 1, 6, 12, 18, and 24 months, and at 5 years. The main exposures were ever being overweight during 1-24 months using each of three cutpoints: CDC WFL ≥ 95th percentile, WHO WFL or BMI ≥ 97.7th percentile. The main outcome was obesity at 5 years (CDC BMI ≥ 95th percentile). We calculated multivariable odds ratios (ORs), adjusted for age, sex, race/ethnicity, and year. At 5 years, 10.8% of participants were obese. During 1-24 months, 21.3, 18.3, and 20.2% were ever overweight using CDC WFL, WHO WFL, and WHO BMI cutpoints, respectively. ORs (95% confidence interval (CI)) for associations of ever being overweight during 1-24 months with obesity at 5 years were 6.0 (5.4, 6.6), 6.3 (5.7, 7.0), and 6.0 (5.4, 6.7), respectively. Ever being overweight in the first 2 years of life is a strong predictor of obesity at 5 years. CDC WFL, WHO WFL, and WHO BMI cutpoints for overweight in early childhood provided similar estimates of later obesity risk.

  10. Histopathological confirmation of similar intramucosal distribution of fluorescein in both intravenous administration and local mucosal application for probe-based confocal laser endomicroscopy of the normal stomach

    PubMed Central

    Nonaka, Kouichi; Ohata, Ken; Ban, Shinichi; Ichihara, Shin; Takasugi, Rumi; Minato, Yohei; Tashima, Tomoaki; Matsuyama, Yasushi; Takita, Maiko; Matsuhashi, Nobuyuki; Neumann, Helmut

    2015-01-01

    Probe-based confocal laser endomicroscopy (pCLE) is capable of acquiring in vivo magnified cross-section images of the gastric mucosa. Intravenous injection of fluorescein sodium is used for confocal imaging. However, it is still under debate if local administration of the dye to the mucosa is also effective for confocal imaging as it is not yet clear if topical application also reveals the intramucosal distribution of fluorescein. The objective of this study was to evaluate the intramucosal distribution of fluorescein sodium after topical application and to compare the distribution to the conventional intravenous injection used for confocal imaging. pCLE of the stomach uninfected with Helicobacter pylori was performed in a healthy male employing intravenous administration and local mucosal application of fluorescein. The mucosa of the lower gastric body was biopsied 1 min and 5 min after intravenous administration or local mucosal application of fluorescein, and the distribution of fluorescein in the biopsy samples was examined histologically. Green fluorescence was already observed in the cytoplasm of fundic glandular cells in the biopsied deep mucosa 1 min after local mucosal application of fluorescein. It was also observed in the foveolar lumen and inter-foveolar lamina propria, although it was noted at only a few sites. In the tissue biopsied 5 min after the local mucosal application of fluorescein, green fluorescence was more frequently noted in the cytoplasm of fundic glandular cells than in that 1 min after the local mucosal application of fluorescein, although obvious green fluorescence was not identified in the foveolar lumen or inter-foveolar lamina propria. The distribution of intravenously administered fluorescein in the cytoplasm of fundic glandular cells was also clearly observed similarly to that after local mucosal application of fluorescein. Green fluorescence in more cells was observed in many cells 5 min after intravenous administration compared

  11. Quantitative changes in the frequency and distribution of the C-cell population in the rat thyroid gland with age.

    PubMed

    Martín-Lacave, I; Conde, E; Montero, C; Galera-Davidson, H

    1992-10-01

    The development of calcitonin cells (C-cells) was investigated in rat thyroid glands from birth to 120 days, using an immunoperoxidase technique and a point-counting method. The proportion of C-cells to follicular cells was 4.5% on the day of birth and increased progressively to 10.4% by 120 days. The highest density of C-cells was noted in the mid-region of the lobes along a longitudinal axis. The caudal and cephalic regions of the lobes contained smaller numbers of C-cells. The C-cells tended to be more numerous in the posterior aspects of the lobes. Although the numbers of C-cells in 120-day-old animal were markedly increased as compared to animals at the time of birth, the cell distributions within the glands were similar at all ages.

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

    NASA Astrophysics Data System (ADS)

    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.

  13. DISTRIBUTION OF CARIOUS AND NON-CARIOUS CERVICAL LESIONS AND GINGIVAL RECESSION AT AGE RELATED ASPECTS.

    PubMed

    Mamaladze, M; Khutsishvili, L; Zarkua, E

    2016-07-01

    The current study aims at differentiating carious and/or non-carious diseases developed in Class 5 region and detecting the distribution rate at the age aspects. The study was conducted at the Dental Clinicand Educational-Research Center "Unident" LTD and Dental Clinic "Dens". 256 patients were involved in the study. All patients underwent a routine dental examination, while rentgenovisiography and CT were performed in case of need. For gathering the detailed medical history and integrated study of Class 5 defects, a special questionnaire/survey, providing detailed information on each patient, was developed. The conducted study revealed the following: The patients were divided into 3 age groups: 16-30 of ages (77 patients, I study group), 30-50 of ages (97 patients, II study group) and 50-70 of ages (82, III study group), respectively. In total 5802 teeth were examined. The subject of our interest was identification of intact and damaged teeth (affected with caries and non-carious diseases) in the above-mentioned contingent. It was found that carious disease of cervical zone of tooth (Class 5) most often was revealed in 30-50 age group (202 cases), which is 1.8-fold higher than the same index in the I study group (144) and 1.4-fold higher in the III study group (183), respectively; The highest rate of non-carious lesions (erosion, abrasion, abfraction) of dental neck was recorded in examined 50-70 age group (294 cases), which was 4.6 -fold higher than in the I study group (64) and 2.1 -fold higher in II study group (140), respectively; The lowest incidence of gingival recession was in the I study group (65 cases), which is 6.3 -fold lower than in the II study group (412) and 7.5-fold lower than - the III group (493). PMID:27661270

  14. Comparison of particle-tracking and lumped-parameter models for determining groundwater age distributions and nitrate in water-supply wells, Central Valley, California, USA

    NASA Astrophysics Data System (ADS)

    Jurgens, B. C.; Bohlke, J. K.; Kauffman, L. J.; Belitz, K.

    2013-12-01

    Age distributions for 30 production wells (mostly public-supply) were determined using two methods: 1) calibration of age tracer data with lumped parameter models (LPMs) and 2) by advective particle tracking (PT) simulations using MODPATH and a regional steady-state groundwater flow model. The LPMs were calibrated with measurements of 3H, 3He(trit), and 14C by minimizing the Chi-square test statistic using a non-linear solver. A partial exponential model (PEM) was the primary LPM used in this study and a combination of two PEMs were used in cases where binary age mixtures were identified. The PEM is a reformulated version of the exponential model that is parameterized to simulate the age distribution in a well that is screened over any finite interval within the aquifer. The regional numerical model was calibrated to water-levels and gradients, and simulated PT age tracer concentrations were calibrated to the MODPATH porosity value. Age distributions were then used to predict nitrate concentrations in wells using agricultural application rates of nitrate in the central eastside of the San Joaquin Valley, California. Both methods showed that wells in the study area captured groundwater with a broad range of ages, spanning decades to millennia. Age distributions from the LPMs predicted age tracer and nitrate concentrations more accurately than the regional PT simulation; whereas PT simulations incorporating more detailed information about water-levels and hydraulic gradients near wells also provided good fits. 14C concentrations were not simulated well by the regional steady-state model, especially for wells with a significant fraction of old groundwater, because the model simulates the current, perturbed system and does not simulate recharge rates and velocities of the predevelopment system. Results from the LPMs yielded an average recharge rate of 0.55 m/yr, which was similar to the average recharge rate of 0.54 m/yr determined from a water budget analysis for the

  15. Maize varieties released in different eras have similar root length density distributions in the soil, which are negatively correlated with local concentrations of soil mineral nitrogen.

    PubMed

    Ning, Peng; Li, Sa; White, Philip J; Li, Chunjian

    2015-01-01

    Larger, and deeper, root systems of new maize varieties, compared to older varieties, are thought to have enabled improved acquisition of soil resources and, consequently, greater grain yields. To compare the spatial distributions of the root systems of new and old maize varieties and their relationships with spatial variations in soil concentrations of available nitrogen (N), phosphorus (P) and potassium (K), two years of field experiments were performed using six Chinese maize varieties released in different eras. Vertical distributions of roots, and available N, P and K in the 0-60 cm soil profile were determined in excavated soil monoliths at silking and maturity. The results demonstrated that new maize varieties had larger root dry weight, higher grain yield and greater nutrient accumulation than older varieties. All varieties had similar total root length and vertical root distribution at silking, but newer varieties maintained greater total root length and had more roots in the 30-60 cm soil layers at maturity. The spatial variation of soil mineral N (Nmin) in each soil horizon was larger than that of Olsen-P and ammonium-acetate-extractable K, and was inversely correlated with root length density (RLD), especially in the 0-20 cm soil layer. It was concluded that greater acquisition of mineral nutrients and higher yields of newer varieties were associated with greater total root length at maturity. The negative relationship between RLD and soil Nmin at harvest for all varieties suggests the importance of the spatial distribution of the root system for N uptake by maize.

  16. Maize Varieties Released in Different Eras Have Similar Root Length Density Distributions in the Soil, Which Are Negatively Correlated with Local Concentrations of Soil Mineral Nitrogen

    PubMed Central

    Ning, Peng; Li, Sa; White, Philip J.; Li, Chunjian

    2015-01-01

    Larger, and deeper, root systems of new maize varieties, compared to older varieties, are thought to have enabled improved acquisition of soil resources and, consequently, greater grain yields. To compare the spatial distributions of the root systems of new and old maize varieties and their relationships with spatial variations in soil concentrations of available nitrogen (N), phosphorus (P) and potassium (K), two years of field experiments were performed using six Chinese maize varieties released in different eras. Vertical distributions of roots, and available N, P and K in the 0–60 cm soil profile were determined in excavated soil monoliths at silking and maturity. The results demonstrated that new maize varieties had larger root dry weight, higher grain yield and greater nutrient accumulation than older varieties. All varieties had similar total root length and vertical root distribution at silking, but newer varieties maintained greater total root length and had more roots in the 30–60 cm soil layers at maturity. The spatial variation of soil mineral N (Nmin) in each soil horizon was larger than that of Olsen-P and ammonium-acetate-extractable K, and was inversely correlated with root length density (RLD), especially in the 0–20 cm soil layer. It was concluded that greater acquisition of mineral nutrients and higher yields of newer varieties were associated with greater total root length at maturity. The negative relationship between RLD and soil Nmin at harvest for all varieties suggests the importance of the spatial distribution of the root system for N uptake by maize. PMID:25799291

  17. Differential Protein Distribution between the Nucleus and Mitochondria: Implications in Aging

    PubMed Central

    Lionaki, Eirini; Gkikas, Ilias; Tavernarakis, Nektarios

    2016-01-01

    The coordination of nuclear and mitochondrial genomes plays a pivotal role in maintenance of mitochondrial biogenesis and functionality during stress and aging. Environmental and cellular inputs signal to nucleus and/or mitochondria to trigger interorganellar compensatory responses. Loss of this tightly orchestrated coordination results in loss of cellular homeostasis and underlies various pathologies and age-related diseases. Several signaling cascades that govern interorganellar communication have been revealed up to now, and have been classified as part of the anterograde (nucleus to mitochondria) or retrograde (mitochondrial to nucleus) response. Many of these molecular pathways rely on the dual distribution of nuclear or mitochondrial components under basal or stress conditions. These dually localized components usually engage in specific tasks in their primary organelle of function, whilst upon cellular stimuli, they appear in the other organelle where they engage in the same or a different task, triggering a compensatory stress response. In this review, we focus on protein factors distributed between the nucleus and mitochondria and activated to exert their functions upon basal or stress conditions. We further discuss implications of bi-organellar targeting in the context of aging.

  18. Differential Protein Distribution between the Nucleus and Mitochondria: Implications in Aging

    PubMed Central

    Lionaki, Eirini; Gkikas, Ilias; Tavernarakis, Nektarios

    2016-01-01

    The coordination of nuclear and mitochondrial genomes plays a pivotal role in maintenance of mitochondrial biogenesis and functionality during stress and aging. Environmental and cellular inputs signal to nucleus and/or mitochondria to trigger interorganellar compensatory responses. Loss of this tightly orchestrated coordination results in loss of cellular homeostasis and underlies various pathologies and age-related diseases. Several signaling cascades that govern interorganellar communication have been revealed up to now, and have been classified as part of the anterograde (nucleus to mitochondria) or retrograde (mitochondrial to nucleus) response. Many of these molecular pathways rely on the dual distribution of nuclear or mitochondrial components under basal or stress conditions. These dually localized components usually engage in specific tasks in their primary organelle of function, whilst upon cellular stimuli, they appear in the other organelle where they engage in the same or a different task, triggering a compensatory stress response. In this review, we focus on protein factors distributed between the nucleus and mitochondria and activated to exert their functions upon basal or stress conditions. We further discuss implications of bi-organellar targeting in the context of aging. PMID:27695477

  19. Do predators influence the distribution of age-0 kokanee in a Colorado Reservoir?

    USGS Publications Warehouse

    Hardiman, J.M.; Johnson, B.M.; Martinez, P.J.

    2004-01-01

    Seasonal changes in reservoir conditions such as productivity, light, and temperature create spatiotemporal variation in habitat that may segregate or aggregate predators and prey, producing implications for the distribution, growth, and survival of fishes. We used hydroacoustics to document the diel vertical distribution of age-0 kokanee Oncorhynchus nerka relative to environmental gradients at Blue Mesa Reservoir, Colorado, during May-August of 2002. Temperature, light, and zooplankton density profiles were examined relative to foraging conditions for kokanee and their primary predator, lake trout Salvelinus namaycush. Age-0 kokanee displayed large diel vertical migrations in May despite the lack of an energetic advantage before reservoir stratification. Age-0 kokanee minimized near-surface foraging at this time, perhaps to avoid predation by visual predators, such as lake trout, in the well-lit surface waters. Strong reservoir stratification in midsummer appeared to provide a thermal refuge from lake trout that the kokanee exploited. By August vertical migrations were shallow and most kokanee remained in the epilimnion throughout the day. Although the energetic implications of the late-summer strategy are unclear, it appears that kokanee were responding to changes in their predator environment. A robust model for kokanee diel vertical migration across a range of systems should include a predator avoidance component.

  20. Epigenetic contribution to age distribution of mortality within the Penna model.

    PubMed

    Magdoń-Maksymowicz, M S; Maksymowicz, A Z

    2015-06-01

    Some modifications of the simple asexual Penna model, enriched by epigenetic contributions, are presented. The standard bit-string Penna model of biological aging and population evolution is based on an inherited DNA structure which defines the future life of a newly born individuals, when genes are activated by the biological clock, and the predefined genetic death is fully controlled by the number of defected genes. Epigenomes allow to introduce additional mechanism of gene activation or silencing without affecting the DNA genome itself. It may be either inherited or may reflect external, environmental factors. In the presented model, information read from the introduced epigenome may alter gene expression that may be stopped or re-activated. We concentrate on the influence of epigenetics on the age a distribution of genetic mortality m(a). Changes in m(a) are strong for the case of inherited epigenetic contribution with nearly perfect inheritance and 'positive' epigenome that partly ignores the 'bad' mutations. We conclude that the epigenetic contribution may influence population structure m(a) and could be, at least partly, responsible for deviation of m(a) distribution from the Gompertz law. In short, we claim that proposed epigenetic contribution may be seen as a candidate for possible explanation of observed deviation from the Gompertz law, also among senior members of society. A very simple model was used in this paper and many crucial mechanisms of biological aging were omitted. Therefore, further work based on a more realistic models is necessary. PMID:25666268

  1. The Old Imbrium Hypothesis. [revision for KREEP materials formation age and distribution

    NASA Technical Reports Server (NTRS)

    Schonfeld, E.; Meyer, C., Jr.

    1973-01-01

    It is proposed that the order of lunar events was such that the Imbrium event predates the formation of the lunar rock type called KREEP. This hypothesis is used to explain the distribution of KREEP in the regions of Imbrium ejecta and the location of KREEP within the Imbrium and Procellarum mare regions. Model ages of KREEP materials have been previously interpreted to mean that their 'formation' age (time of initial extrusion) is about 4.3 to 4.4 AE. Consequently it is suggested that the Imbrium impact was before 4.3 to 4.4 AE rather than at about 3.9 AE, as is currently believed. This Old Imbrium Hypothesis is not yet proven, but seems to be consistent with a large variety of basic lunar observations.

  2. Gender- and Age-Specific REE and REE/FFM Distributions in Healthy Chinese Adults

    PubMed Central

    Cheng, Yu; Yang, Xue; Na, Li-Xin; Li, Ying; Sun, Chang-Hao

    2016-01-01

    Basic data on the resting energy expenditure (REE) of healthy populations are currently rare, especially for developing countries. The aims of the present study were to describe gender- and age-specific REE distributions and to evaluate the relationships among glycolipid metabolism, eating behaviors, and REE in healthy Chinese adults. This cross-sectional survey included 540 subjects (343 women and 197 men, 20–79 years old). REE was measured by indirect calorimetry and expressed as kcal/day/kg total body weight. The data were presented as the means and percentiles for REE and the REE to fat-free mass (FFM) ratio; differences were described by gender and age. Partial correlation analysis was used to analyze the correlations between REE, tertiles of REE/FFM, and glycolipid metabolism and eating behaviors. In this study, we confirmed a decline in REE with age in women (p = 0.000) and men (p = 0.000), and we found that men have a higher REE (p = 0.000) and lower REE/FFM (p = 0.021) than women. Furthermore, we observed no associations among glycolipid metabolism, eating behaviors, and REE in healthy Chinese adults. In conclusion, the results presented here may be useful to clinicians and nutritionists for comparing healthy and ill subjects and identifying changes in REE that are related to aging, malnutrition, and chronic diseases. PMID:27598192

  3. Gender- and Age-Specific REE and REE/FFM Distributions in Healthy Chinese Adults.

    PubMed

    Cheng, Yu; Yang, Xue; Na, Li-Xin; Li, Ying; Sun, Chang-Hao

    2016-01-01

    Basic data on the resting energy expenditure (REE) of healthy populations are currently rare, especially for developing countries. The aims of the present study were to describe gender- and age-specific REE distributions and to evaluate the relationships among glycolipid metabolism, eating behaviors, and REE in healthy Chinese adults. This cross-sectional survey included 540 subjects (343 women and 197 men, 20-79 years old). REE was measured by indirect calorimetry and expressed as kcal/day/kg total body weight. The data were presented as the means and percentiles for REE and the REE to fat-free mass (FFM) ratio; differences were described by gender and age. Partial correlation analysis was used to analyze the correlations between REE, tertiles of REE/FFM, and glycolipid metabolism and eating behaviors. In this study, we confirmed a decline in REE with age in women (p = 0.000) and men (p = 0.000), and we found that men have a higher REE (p = 0.000) and lower REE/FFM (p = 0.021) than women. Furthermore, we observed no associations among glycolipid metabolism, eating behaviors, and REE in healthy Chinese adults. In conclusion, the results presented here may be useful to clinicians and nutritionists for comparing healthy and ill subjects and identifying changes in REE that are related to aging, malnutrition, and chronic diseases. PMID:27598192

  4. Prevalence, age distribution and aetiology of bronchiectasis: a retrospective study on 144 symptomatic patients.

    PubMed

    Scala, R; Aronne, D; Palumbo, U; Montella, L; Giacobbe, R; Martucci, P; Del Prato, B

    2000-04-01

    The incidence of bronchiectasis (BCT) has probably decreased in developed countries in recent years, but reliable statistical data on its occurrence are still lacking. The aim of the present study was to retrospectively evaluate the prevalence, age distribution and aetiology of BCT, diagnosed in a selected series of symptomatic patients of a Western country by using bronchography. The authors analysed the main known predisposing and associated conditions (PACs), and the occurrence and age distribution of BCT in 144 consecutive patients who underwent bronchological examination (fibreoptic bronchoscopy and bronchography) in the years 1987-1994 because of recurrent purulent bronchitis and/or haemoptysis. The overall prevalence of BCT was 34% (49/144); its age distribution was: 17.2% (0-10 yrs), 43.7% (11-20 yrs), 38% (21-30 yrs), 37.5% (31-40 yrs), 33.3% (41-50 yrs), 40% (51-60 yrs), and 20% (61-70 yrs). Thirty-one PACs were found in 29/144 patients of the whole study group. The prevalence of BCT was significantly higher in the subgroup of 29 patients with PACs than in the subgroup of 115 patients without PACs (75.9% versus 23.5%; p < 0000001). The aetiology of BCT was mainly unexplained, as it was only possible to detect 24 PACs in 22/49 patients with BCT (44.9%): congenital, genetic and immune disorders (eight), localized airways obstructive diseases (five), pulmonary infections (three), bronchial asthma (two), pulmonary lobar fibrosis (two), ulcerative colitis (two), dermatomiositis (one), and toxin inhalation (one). The authors conclude that bronchiectasis still occurs in a large percentage of symptomatic patients of a developed country in the post-antimicrobial era, especially in the second to sixth decades, as well as in the presence of predisposing and associated conditions; its aetiology remains unknown in more than half of cases.

  5. [Root system spatial distribution of different aged Armeniaca vulgaris cv. Luntaibaixing in arid oasis under irrigation].

    PubMed

    Wang, Shi-Wei; Pan, Cun-De

    2012-09-01

    By the methods of layered digging and image scanning analysis, this paper studied the root system spatial distribution of different aged Armeniaca vulgaris cv. Luntaibaixing in arid oasis under irrigation. The root system of A. vulgaris cv. Luntaibaixing was mainly constituted by fine roots (d < or = 1 mm), while medium roots (12 mm) only had a small proportion. For the trees aged 5-year old, 10-year old, and 15-year old, the percentage of fine root length in the total root length was 90.9%, 88.4%, and 79.9% respectively, the root length density increased with tree age, and the length density of the roots with different diameter classes was 15-year old>10-year old>5-year old. In vertical direction, the root length density decreased after an initial decrease, and the root dry mass density had a significant difference between soil layers. The intensive distribution region of the root biomass density for the trees aged 5-year old, 10-year old, and 15-year old was 30-80 cm, 30-100 cm, and 30-100 cm soil depth within the 200 cm range from the trees, respectively. In horizontal direction, the root dry mass density at different distances from the trees had significant difference, i. e., the farther the distance from the tree trunk, the smaller the root dry mass density. In order to decrease the overlap between the tree line and to reduce water and nutrient competition, the row ledge of A. vulgaris cv. Luntaibaixing in arid oasis under irrigation should not be less than 6 m. PMID:23285988

  6. [Root system spatial distribution of different aged Armeniaca vulgaris cv. Luntaibaixing in arid oasis under irrigation].

    PubMed

    Wang, Shi-Wei; Pan, Cun-De

    2012-09-01

    By the methods of layered digging and image scanning analysis, this paper studied the root system spatial distribution of different aged Armeniaca vulgaris cv. Luntaibaixing in arid oasis under irrigation. The root system of A. vulgaris cv. Luntaibaixing was mainly constituted by fine roots (d < or = 1 mm), while medium roots (12 mm) only had a small proportion. For the trees aged 5-year old, 10-year old, and 15-year old, the percentage of fine root length in the total root length was 90.9%, 88.4%, and 79.9% respectively, the root length density increased with tree age, and the length density of the roots with different diameter classes was 15-year old>10-year old>5-year old. In vertical direction, the root length density decreased after an initial decrease, and the root dry mass density had a significant difference between soil layers. The intensive distribution region of the root biomass density for the trees aged 5-year old, 10-year old, and 15-year old was 30-80 cm, 30-100 cm, and 30-100 cm soil depth within the 200 cm range from the trees, respectively. In horizontal direction, the root dry mass density at different distances from the trees had significant difference, i. e., the farther the distance from the tree trunk, the smaller the root dry mass density. In order to decrease the overlap between the tree line and to reduce water and nutrient competition, the row ledge of A. vulgaris cv. Luntaibaixing in arid oasis under irrigation should not be less than 6 m.

  7. Methods and evaluation of frequency aging in distributed-feedback laser diodes for rubidium atomic clocks.

    PubMed

    Matthey, Renaud; Affolderbach, Christoph; Mileti, Gaetano

    2011-09-01

    Distributed-feedback laser diodes emitting at 780 nm have been evaluated, with respect to the aging of the injection current required for reaching the rubidium D2 resonance line. Results obtained for lasers operating in air and in vacuum for 9 months are reported. When operated at constant temperature, the laser current required for emission at the wavelength of the desired atomic resonance is found to decrease by 50 to 80 μA per month. The impact of this result on the lifetime and long-term performances of laser-pumped rubidium atomic clocks is discussed.

  8. The galactic habitable zone and the age distribution of complex life in the Milky Way.

    PubMed

    Lineweaver, Charles H; Fenner, Yeshe; Gibson, Brad K

    2004-01-01

    We modeled the evolution of the Milky Way Galaxy to trace the distribution in space and time of four prerequisites for complex life: the presence of a host star, enough heavy elements to form terrestrial planets, sufficient time for biological evolution, and an environment free of life-extinguishing supernovae. We identified the Galactic habitable zone (GHZ) as an annular region between 7 and 9 kiloparsecs from the Galactic center that widens with time and is composed of stars that formed between 8 and 4 billion years ago. This GHZ yields an age distribution for the complex life that may inhabit our Galaxy. We found that 75% of the stars in the GHZ are older than the Sun.

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

    USGS Publications Warehouse

    Jurgens, Bryant; Bohlke, 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.

  10. Size frequency distribution of Martian craters and relative age of light and dark terrains.

    NASA Technical Reports Server (NTRS)

    Woronow, A.; King, E. A., Jr.

    1972-01-01

    Light and dark terrains in and around Meridiani Sinus, mapped on the imagery from Mariner 6 and Mariner 7, were found to have significantly different cumulative size frequency distributions of craters. The light terrain on a mosaic of frames 6N11, 6N13, and 6N19 has a greater proportion of large craters and a lesser proportion of smaller craters than the dark terrain on the same frames. The light terrain is interpreted to be generally older than the dark terrain. The filling or partial filling of the smaller craters on the light terrain by surface detritus is suggested. Several wide-angle frames have remarkably similar cumulative crater size frequency distributions that may be representative of a large portion of the Martian surface.

  11. Effect of backpack position on foot weight distribution of school-aged children

    PubMed Central

    Kim, Kyung; Kim, Chang Ju; Oh, Duck-Won

    2015-01-01

    [Purpose] In the present study, we aimed to determine the effects of backpack position on foot weight distribution of standing school-aged children. [Subjects] Thirty school-aged children volunteered to participate in this study. [Methods] The subjects randomly performed four types of carrying a backpack: no backpack (condition-1), carrying a backpack at C7 (condition-2), carrying a backpack at 10 cm below C7 (condition-3), and carrying a backpack at 20 cm below C7 (condition-4). [Results] Statistically significant differences were noted in the anterior and posterior pressure values, and in the anterior-to-posterior ratio, among the four conditions (p < 0.05). Post-hoc analysis indicated that the pressure value of condition-4 was significantly lower in the anterior foot region and higher in the posterior foot region than in condition-2 and condition-3. In addition, the anterior-to-posterior ratio was lower in condition-4 than in condition-2 and condition-3. [Conclusion] These findings suggest that carrying a backpack in a higher position, with fastening of the shoulder strap, may be more favorable for normalizing the foot weight distribution. PMID:25931722

  12. Effect of backpack position on foot weight distribution of school-aged children.

    PubMed

    Kim, Kyung; Kim, Chang Ju; Oh, Duck-Won

    2015-03-01

    [Purpose] In the present study, we aimed to determine the effects of backpack position on foot weight distribution of standing school-aged children. [Subjects] Thirty school-aged children volunteered to participate in this study. [Methods] The subjects randomly performed four types of carrying a backpack: no backpack (condition-1), carrying a backpack at C7 (condition-2), carrying a backpack at 10 cm below C7 (condition-3), and carrying a backpack at 20 cm below C7 (condition-4). [Results] Statistically significant differences were noted in the anterior and posterior pressure values, and in the anterior-to-posterior ratio, among the four conditions (p < 0.05). Post-hoc analysis indicated that the pressure value of condition-4 was significantly lower in the anterior foot region and higher in the posterior foot region than in condition-2 and condition-3. In addition, the anterior-to-posterior ratio was lower in condition-4 than in condition-2 and condition-3. [Conclusion] These findings suggest that carrying a backpack in a higher position, with fastening of the shoulder strap, may be more favorable for normalizing the foot weight distribution. PMID:25931722

  13. Temperature, age and crust thickness distributions of Loki Patera on Io: implications for resurfacing mechanism

    NASA Technical Reports Server (NTRS)

    Davies, A. G.

    2003-01-01

    A high-spatial-resolution, multi-wavelength observation by the Galileo NIMS instrument has been analysed to determine the temperature and area distribution of a large portion of the ionian volcano Loki Patera. The temperatures of the cooler components from a two-temperature fit to the data can be used to determine ages of the surface. The age of the floor along a profile across the floor of the caldera ranges from 10 to 80 days. This puts the start of the resurfacing in July/early August 2001, yielding a resurfacing rate of approximately 1 km/day, with the new lava spreading from the SW corner of the caldera in a NE direction. This rate is consistent with resurfacing by foundering of the crust on a lava lake. However,the temperature distribution may also result from the emplacement of flows. Implied crust thicknesses (derived using a lava cooling model) range from 2.6 to 0.9 m.

  14. A cross-cultural comparison between Spain and the USA: temperament and character distribution by sex and age.

    PubMed

    Al-Halabí, Susana; Herrero, Rocío; Sáiz, Pilar A; García-Portilla, María Paz; Errasti, José M; Corcoran, Paul; Bascarán, María Teresa; Bousoño, Manuel; Lemos, Serafín; Bobes, Julio

    2011-04-30

    The Unified Biosocial Theory of Personality developed by Cloninger has been applied in different cultures. Distribution by age and sex of the Temperament and Character Inventory (TCI) dimensions were assessed cross-culturally for samples in Spain and the USA. Three non-clinical samples were included: i) 404 participants from Asturias (Spain); ii) 240 participants from Burgos (Spain); and iii) 300 adults from St. Louis (USA). Each participant was assessed by means of the TCI. A significant negative correlation between NS and both HA (r=-0.329; P<0.01) and P (r=-0.217; P<0.01) was found in the study sample, as well as significant effects of age in NS, HA, RD, and C for women and in NS and HA for men, and also of sex in HA and RD. Personality dimensions for the two Spanish samples appear to be similar (differences in HA4 and RD) compared to those for the US sample (differences in NS, HA, RD and P). Findings support Cloninger's theory about differences between men and women, but not regarding the intercorrelations between temperament dimensions.

  15. A new method for evaluating age distributions of detrital zircon datasets by incorporating discordant data

    NASA Astrophysics Data System (ADS)

    Reimink, Jesse; Davies, Joshua; Rojas, Xavier; Waldron, John

    2015-04-01

    U-Pb ages from detrital zircons play an important role in sediment provenance studies. However, U-Pb ages from detrital zircon populations often contain a discordant component, which is traditionally removed before the age data are interpreted. Many different processes can create discordant analyses, with the most important being Pb-loss and mixing of distinct zircon age domains during analysis. Discordant ages contain important information regarding the history of a detrital zircon population, for example the timing of Pb-loss or metamorphism, and removing these analyses may significantly bias a zircon dataset. Here we present a new technique for analyzing detrital zircon populations that uses all U-Pb analyses, independent of discordance. We have developed computer code that evaluates the relative likelihood of discordia lines based on their proximity to discordant data points. When two or more data points lie on or near a discordia line the likelihood associated with that line increases. The upper and lower intercepts of each discordia line, as well as the relative likelihood along that line, are stored, and the likelihood of upper and lower intercepts are plotted with age. There are many benefits to using this technique for analysis of detrital zircon datasets. By utilizing the discordant analyses we allow for the addition of upper and lower intercept information to conventional analysis techniques (i.e. probability density functions or kernel density estimators). We are then able to use a much stricter discordance filter (e.g. < 3%) when analyzing 'concordant' data, thereby increasing the reliability of Pb/Pb ages used in the traditional analysis. Additionally, by not rejecting discordant data from zircon datasets we potentially reduce the overall bias in the analysis, which is a critical step in detrital zircon studies. This new technique is relatively quick and uses traditional analytical results, while the upper and lower intercept information is obtained

  16. Distribution pattern and the risks of OPCs, PHAs and PCBs in aged refuses from landfill.

    PubMed

    Lou, Ziyang; Li, Anding; Tai, Jun; Yuan, Wenxiang; Zhu, Nanwen; Zhao, Youcai

    2016-09-01

    Persistent organic pollutants (POPs) are the urgent risk for landfill, and should be considered before the landfill reclamation and resource. In this work, the distribution pattern of selected POPs in landfill and their ecological risks were investigated and assessed. The Σ20OCPs, Σ16PAHs and Σ19PCBs were around 157.4-329.2, 4103-19,190, and 79.1-340.3μgkg(-1) in aged refuses, with the mean value of 206.6, 8645.4, and 155.1μgkg(-1). While those in soil covers were only 6.3-75.4, 125.5-515.3 and 2.6-43.4μgkg(-1), with the mean value of 33.7, 257.7, and 24.0μgkg(-1), respectively. The maximum OPCs, PHAs and PCBs were in aged refuse with 13, 7, 10 disposal years. Whereas, the corresponding top content in soil covers were in 10, 13 and 16years, meaning that aged refuses were not the direct source for soil covers. Among 20 OCPs measured, α-HCH, δ-HCH, Dieldrin, and Endrin were presented in all aged refuses, with the mean concentration of 93.6, 52.1, 3.9 and 4.7μgkg(-1), respectively. For PAHs, PHE, FLU and PYR were the main composition, and reached to 1535, 1224, 1187μgkg(-1). The Σ7CarPAHs occupied around 33.3-49.9% of total Σ16PAHs tested, and could be used as the indictor for PAHs pollutant in landfill. PCB-5 content was around 40.7-263.3μgkg(-1) in aged refuses, and occupied around 51.5-81.8% of Σ19PCBs measured. The HCHs and DDTs in aged refuses were below the national standard GB15618-1995, and the corresponding Σ19PCBs concentrations met the standard of GB 13015-91, suggesting that aged refuse are accepted for the further utilization process. PMID:26994555

  17. Distribution of epiphytic bacteria on olive leaves and the influence of leaf age and sampling time.

    PubMed

    Ercolani, G L

    1991-12-01

    Mesophilic heterotrophic, aerobic or facultatively anaerobic bacteria that grow on yeast tryptone glucose extract agar were isolated from the surface of olive leaves of 3 or 4 different ages in January, April, July, and October from 1984 to 1989. Unweighted average linkage cluster analysis on either the Jaccard coefficient or the simple matching coefficient recovered 1,701 representative strains in 32 phena defined at the 70% and 80% similarity level, respectively. Of these, 25 were identified to genus or lower level. From the identity of the representative strains, the frequency of occurrence among the phylloplane bacteria over the 6-year period was estimated at 51% forPseudomonas syringae, followed byXanthomonas campestris (6.7%),Erwinia herbicola (6%),Acetobacter aceti (4.7%),Gluconobacter oxydans (4.3%),Pseudomonas fluorescens (3.9%),Bacillus megaterium (3.8%),Leuconostoc mesenteroides subsp.dextranicum (3.1%),Lactobacillus plantarum (2.8%),Curtobacterium plantarum (2.2%),Micrococcus luteus (2.2%),Arthrobacter globiformis (1.4%),Klebsiella planticola (1.2%),Streptococcus faecium (1.2%),Clavibacter sp. (0.98%),Micrococcus sp. (0.82%),Serratia marcescens (0.81%),Bacillus subtilis (0.57%),Cellulomonas flavigena (0.4%),Erwinia sp. (0.37%),Zymomonas mobilis (0.3%),Bacillus sp. (0.29%),Alcaligenes faecalis (0.27%),Erwinia carotovora (0.08%), andPseudomonas aeruginosa (0.04%). Bacterial communities on leaves of a given age at a given time during any one year displayed a very similar structure but differed significantly from those on the leaves of the same age at a different time or on the leaves of a different age at any time during any one year. Communities on the leaves of a given age at a given time of the year were invariably dominated by one or another of only 9 taxa, which accounted for 22 to 98.5% of the isolates from those leaves. The communities on 10- and 13-month-old leaves were invariably made up of fewer taxa than those on younger leaves at the same time

  18. A mitochondrial location for haemoglobins--dynamic distribution in ageing and Parkinson's disease.

    PubMed

    Shephard, Freya; Greville-Heygate, Oliver; Marsh, Oliver; Anderson, Susan; Chakrabarti, Lisa

    2014-01-01

    Haemoglobins are iron-containing proteins that transport oxygen in the blood of most vertebrates. The mitochondrion is the cellular organelle which consumes oxygen in order to synthesise ATP. Mitochondrial dysfunction is implicated in neurodegeneration and ageing. We find that α and β haemoglobin (Hba and Hbb) proteins are altered in their distribution in mitochondrial fractions from degenerating brain. We demonstrate that both Hba and Hbb are co-localised with the mitochondrion in mammalian brain. The precise localisation of the Hbs is within the inner membrane space and associated with inner mitochondrial membrane. Relative mitochondrial to cytoplasmic ratios of Hba and Hbb show changing distributions of these proteins during the process of neurodegeneration in the pcd(5j) mouse brain. A significant difference in mitochondrial Hba and Hbb content in the mitochondrial fraction is seen at 31 days after birth, this corresponds to a stage when dynamic neuronal loss is measured to be greatest in the Purkinje Cell Degeneration mouse. We also report changes in mitochondrial Hba and Hbb levels in ageing brain and muscle. Significant differences in mitochondrial Hba and Hbb can be seen when comparing aged brain to muscle, suggesting tissue specific functions of these proteins in the mitochondrion. In muscle there are significant differences between Hba levels in old and young mitochondria. To understand whether the changes detected in mitochondrial Hbs are of clinical significance, we examined Parkinson's disease brain, immunohistochemistry studies suggest that cell bodies in the substantia nigra accumulate mitochondrial Hb. However, western blotting of mitochondrial fractions from PD and control brains indicates significantly less Hb in PD brain mitochondria. One explanation could be a specific loss of cells containing mitochondria loaded with Hb proteins. Our study opens the door to an examination of the role of Hb function, within the context of the mitochondrion

  19. Ages, distributions, and origins of upland coastal dune sheets in Oregon, USA

    USGS Publications Warehouse

    Peterson, C.D.; Stock, E.; Price, D.M.; Hart, R.; Reckendorf, F.; Erlandson, J.M.; Hostetler, S.W.

    2007-01-01

    A total of ten upland dune sheets, totaling 245??km in combined length, have been investigated for their origin(s) along the Oregon coast (500??km in length). The ages of dune emplacement range from 0.1 to 103??ka based on radiocarbon (36 samples) and luminescence (46 samples) dating techniques. The majority of the emplacement dates fall into two periods of late-Pleistocene age (11-103??ka) and mid-late-Holocene age (0.1-8??ka) that correspond to marine low-stand and marine high-stand conditions, respectively. The distribution of both the late-Pleistocene dune sheets (516??km2 total surface area) and the late-Holocene dune sheets (184??km2) are concentrated (90% of total surface area) along a 100??km coastal reach of the south-central Oregon coast. This coastal reach lies directly landward of a major bight (Heceta-Perpetua-Stonewall Banks) on the continental shelf, at depths of 30-200??m below present mean sea level (MSL). The banks served to trap northward littoral drift during most of the late-Pleistocene conditions of lowered sea level (- 50 ?? 20??m MSL). The emerged inner-shelf permitted cross-shelf, eolian sand transport (10-50??km distance) by onshore winds. The depocenter sand deposits were reworked by the Holocene marine transgression and carried landward by asymmetric wave transport during early- to mid-Holocene time. The earliest dated onset of Holocene dune accretion occurred at 8??ka in the central Oregon coast. A northward migration of Northeast Pacific storm tracks to the latitude of the shelf depocenter (Stonewall, Perpetua, Heceta Banks) in Holocene time resulted in eastward wave transport from the offshore depocenter. The complex interplay of coastal morphology, paleosea-level, and paleoclimate yielded the observed peak distribution of beach and dune sand observed along the south-central Oregon coast. ?? 2007 Elsevier B.V. All rights reserved.

  20. Molecular size and molecular size distribution affecting traditional balsamic vinegar aging.

    PubMed

    Falcone, Pasquale Massimiliano; Giudici, Paolo

    2008-08-27

    A first attempt at a semiquantitative study of molecular weight (MW) and molecular weight distribution (MWD) in cooked grape must and traditional balsamic vinegar (TBV) with increasing well-defined age was performed by high-performance liquid size exclusion chromatography (SEC) using dual detection, that is, differential refractive index (DRI) and absorbance (UV-vis) based detectors. With this aim, MW and MWD, including number- and weight-average MW and polydispersity, were determined with respect to a secondary standard and then analyzed. All investigated vinegar samples were recognized as compositionally and structurally heterogeneous blends of copolymers (melanoidins) spreading over a wide range of molecular sizes: the relative MW ranged from 2 to >2000 kDa. The extent of the polymerization reactions was in agreement with the TBV browning kinetics. MWD parameters varied asymptotically toward either upper or lower limits during aging, reflecting a nonequilibrium status of the balance between polymerization and depolymerization reactions in TBV. MWD parameters were proposed as potential aging markers of TBV. PMID:18656930

  1. Aging affects spatial distribution of leg muscle oxygen saturation during ramp cycling exercise.

    PubMed

    Takagi, Shun; Kime, Ryotaro; Murase, Norio; Watanabe, Tsubasa; Osada, Takuya; Niwayama, Masatsugu; Katsumura, Toshihito

    2013-01-01

    We compared muscle oxygen saturation (SmO2) responses in several leg muscles and within a single muscle during ramp cycling exercise between elderly men (n = 8; age, 65 ± 3 years; ELD) and young men (n = 10; age, 23 ± 3 years; YNG). SmO2 was monitored at the distal site of the vastus lateralis (VLd), proximal site of the vastus lateralis (VLp), rectus femoris (RF), vastus medialis (VM), biceps femoris (BF), gastrocnemius lateralis (GL), gastrocnemius medialis (GM), and tibialis anterior (TA) by near-infrared spatial resolved spectroscopy. During submaximal exercise, significantly lower SmO2 at a given absolute work rate was observed in VLd, RF, BF, GL, and TA but not in VLp, VM, and GM in ELD than in YNG. In contrast, at all measurement sites, SmO2 at peak exercise was not significantly different between groups. These results indicate that the effects of aging on SmO2 responses are heterogeneous between leg muscles and also within a single muscle. The lower SmO2 in older men may have been caused by reduced muscle blood flow or altered blood flow distribution.

  2. ANALYSIS OF AGED IN-HOME CARPETING TO DETERMINE THE DISTRIBUTION OF PESTICIDE RESIDUES BETWEEN DUST, CARPET, AND PAD COMPARTMENTS

    EPA Science Inventory

    This report presents results of a study to determine the distribution of pesticides, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) between dust and carpet components in aged carpeting. Carpeting in eight homes in the Research Triangle Area, which...

  3. Levels, tissue distribution, and age-related accumulation of synthetic musk fragrances in Chinese sturgeon (Acipenser sinensis): comparison to organochlorines.

    PubMed

    Wan, Yi; Wei, Qiwei; Hu, Jianying; Jin, Xiaohui; Zhang, Zhaobin; Zhen, Huajun; Liu, Jianyi

    2007-01-15

    Chinese sturgeon (Acipenser sinensis) was listed as a Grade I protected animal in China in 1989, and the observed intersexual phenomenon and sex ratio deviation have suggested that chemicals have posed a risk as environment pollutants. This study analyzed seven musk fragrances in liver, muscle, heart, gonad, stomach, intestines, adipose, gill, pancreas, kidney, gallbladder, and roe from 13 female Chinese sturgeons, and the toxicokinetic behavior of musks were studied and compared with some organochlorines. Of the seven musks, HHCB, AHTN, and musk xylene were detected, and the highest concentrations were observed in adipose tissue: from 33.7 to 62.1 ng/g wet weight (ww), from 1.0 to 5.4 ng/g ww, and from 1.1 to 13 ng/g ww, respectively. Similar to the tissue distribution of DDTs and HCB, musks were detected frequently in high lipid content tissues such as roe, adipose, and liver, suggesting that tissue distribution of musks is controlled by the affinity to lipids. The concentration ratios based on lipid weight between roe and adipose were estimated to be 0.47 for HHCB, 0.58 for AHTN, and 0.51 for musk xylene, and those for the total DDTs and HCB were 0.27 and 0.61, which were relatively low compared with mammals. Relatively high concentrations of p,p'-DDE (68.4-449 ng/g ww) were detected in 10 of total 11 samples, which would cause the feminization of Chinese sturgeons during embryonic development. It was found that lipid-corrected concentrations of HHCB, AHTN, p,p'-DDE, and p,p'-DDD increased with age in female sturgeon, of which the trends were similar to those in fishes and different from those in mammals.

  4. Age and height distribution of holocene transgressive deposits in eastern North Island, New Zealand

    USGS Publications Warehouse

    Ota, Y.; Berryman, K.R.; Hull, A.G.; Miyauchi, T.; Iso, N.

    1988-01-01

    Holocene transgressive deposits are frequently exposed near the present-day coastline of the study area along eastern North Island, New Zealand. They occur in sites of former estuaries that were filled during the postglacial rise in sea level. We present one hundred radiocarbon dates of Holocene transgressive deposits from the study area, ranging in age from ca. 10,000 to 5500 yr B.P. Relative sea level curves up to ca. 6000 yr B.P. were reconstructed for six locations. The curves have similar slopes prior to about 7000 yr B.P., indicating that sea level rise was much more rapid than any tectonic uplift at that time. The postglacial rise in sea level in New Zealand is considered, in general, to have culminated at about 6500 yr B.P. but the upper limit ages of transgressive deposits in our study area vary from ca. 5500 to 7000 yr B.P. At sites where the uplift rate is high the postglacial transgression culminated rather earlier than ca. 6500 yr B.P., and at sites where there is subsidence or there is very low uplift the culmination is later than ca. 6500 yr B.P. Nine of fourteen dates from fossil trees in growth position, that grew in and were buried by estuarine silt, cluster in the age range ca. 8000-8400 yr B.P. These data support the view that there was a minor regression or stillstand in the eustatic sea level rise at that time. Eleven tectonic subregions are recognized in the study area on the basis of average uplift rate. Most of these subregions coincide with those established from the number and ages of younger Holocene marine terraces of probable coseismic origin. ?? 1988.

  5. Similar names for similar biologics.

    PubMed

    Casadevall, Nicole; Felix, Thomas; Strober, Bruce E; Warnock, David G

    2014-10-01

    Approval of the first biosimilar in the USA may occur by the end of 2014, yet a naming approach for biosimilars has not been determined. Biosimilars are highly similar to their biologic reference product but are not identical to it, because of their structural complexity and variations in manufacturing processes among companies. There is a need for a naming approach that can distinguish a biosimilar from its reference product and other biosimilars and ensure accurate tracing of adverse events (AEs) to the administered product. In contrast, generic small-molecule drugs are identical to their reference product and, therefore, share the same nonproprietary name. Clinical trials required to demonstrate biosimilarity for approval may not detect rare AEs or those occurring after prolonged use, and the incidence of such events may differ between a biosimilar and its reference product. The need for precise biologic identification is further underscored by the possibility of biosimilar interchangeability, a US designation that will allow substitution without prescriber intervention. For several biologics, the US Food and Drug Administration (FDA) has used a naming approach that adds a prefix to a common root nonproprietary name, enabling healthcare providers to distinguish between products, avoid medication errors, and facilitate pharmacovigilance. We recommend that the FDA implement a biosimilars naming policy that likewise would add a distinguishable prefix or suffix to the root nonproprietary name of the reference product. This approach would ensure that a biosimilar could be distinguished from its reference product and other biosimilars in patient records and pharmacovigilance databases/reports, facilitating accurate attribution of AEs. PMID:25001080

  6. Linking chemostatic behaviour of streams to storage dynamics and long tails in water age distributions

    NASA Astrophysics Data System (ADS)

    Hrachowitz, Markus; Savenije, Hubert; Soulsby, Chris; Tetzlaff, Doerthe

    2013-04-01

    The water storage and release dynamics at the catchment scale are still incompletely understood. This is in particular true when considering actual particle transport rather than only the hydraulic response. Environmental tracers are frequently instrumental in inferring transport process dynamics. Several recent research papers for example highlight the importance of difference time scales in transport dynamics. While on the short term, particle transport patterns can exhibit considerable variability, many catchments are characterized by near-chemostatic behaviour on the long term. In other words although the tracer response can show considerable fluctuations on the intra-annual scale, it remains surprisingly stable at the inter-annual scale. This suggests (1) that at the long term the composition of water can be largely independent of flow volumes and (2) that water as well as tracers/contaminants, once stored in a catchment can remain in the system for a very long time. Here we use long term (< 20 years) precipitation, flow and tracer (chloride) data of three contrasting upland catchments in the Scottish Highlands to inform integrated conceptual models investigating different mixing assumptions. Using the models as diagnostic tools in a functional comparison, water and tracer fluxes were then tracked with the objective of exploring the origin and pattern of near-chemostatic behaviour which manifests itself in long, power-law tails of water age distributions. The results highlight the potential importance of partial mixing processes in the generation of long tails in water age distributions. However, the degree to which partial mixing influences the generation of long tails is dependent on the hydrological functioning of a catchment. As second influential factor controlling the tailing behaviour of water age distributions was identified to be the interplay of flow path connectivity with the relative importance and timing of different flow paths. This understanding

  7. Prevalence, Type, Distribution, and Severity of Cerebral Palsy in Relation to Gestational Age: A Meta-Analytic Review

    ERIC Educational Resources Information Center

    Himpens, E.; Van den Broeck, C.; Oostra, A.; Calders, P.; Vanhaesebrouck, P.

    2008-01-01

    The aim of this review is to determine the relationship between gestational age (GA) and prevalence, type, distribution, and severity of cerebral palsy (CP). Epidemiological studies with cohorts expressed by GA were assessed. A comprehensive meta-analysis and meta-regression was performed on four fetal age categories. Studies of children with CP…

  8. [Health Care Insurance in France: its impact on income distribution between age and social groups].

    PubMed

    Fourcade, N; Duval, J; Lardellier, R

    2013-08-01

    Our study, based on microsimulation models, evaluates the redistributive impact of health care insurance in France on income distribution between age and social groups. This work sheds light on the debate concerning the respective role of the public health care insurance (PHI) and the private supplemental health care insurance (SHI) in France. The analysis points out that the PHI enables the lowest-income households and the pensioners a better access to health care than they would have had under a complete private SHI. Due to the progressivity of taxes, low-income households contribute less to the PHI and get higher benefits because of a weaker health. Pensioners have low contributions to public health care finance but the highest health care expenditures.

  9. Age rationing and the just distribution of health care: is there a duty to die?

    PubMed

    Battin, Margaret Pabst

    1987-01-01

    The author analyzes the argument that a policy involving distributive justice in the allocation of scarce health care resources, based on the strategy of rational self interest maximation under a veil of ignorance (Rawls/Daniels), would result in an age rationing system of voluntary, socially encouraged, direct termination of the lives of the elderly rather than their medical abandonment. She maintains that such a policy would be a fair response only in a situation of substantial scarcity of resources that cannot be relieved without introducing greater injustices. Battin suggests that some of the current pressure on resources could be reduced by pruning waste and the expenses attributable to paternalistic imposition of treatment and to the practice of defensive medicine. She also advocates reconsideration of societal priorities assigned to various social goods.

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

    PubMed

    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

  11. Distribution, geochemistry and age of the Millennium eruptives of Changbaishan volcano, Northeast China -- A review

    NASA Astrophysics Data System (ADS)

    Sun, Chunqing; You, Haitao; Liu, Jiaqi; Li, Xin; Gao, Jinliang; Chen, Shuangshuang

    2014-04-01

    Large explosive volcanic eruptions generate extensive regional tephra deposits that provide favorable conditions for identifying the source of volcanoes, comparing the sedimentary strata of a region and determining their ages. The tephra layer, referred to as BTm, generated by the Millennium eruption of Changbaishan volcano, is widely distributed in Northeast China, Japan, D.P.R. Korea, and the nearby coastal area of Russia. It forms part of the widespread northeast Asian strata and is significant for establishing an isochronal stratigraphic framework. However, research on the temporal characterization and stratigraphic correlation of associated strata using this tephra layer is mainly concentrated in and near Japan. In northeastern China, this tephra layer is seldom seen and its application in stratigraphic correlations is even rarer. More importantly, the determination of accurate ages for both distal and proximal tephras has been debated, leading to controversy in discussions of its environmental impacts. Stratigraphic records from both distal and proximal Changbaishan ash show that this eruption generally occurred between 1,012 and 1,004 cal yr BP. Geochemical comparison between Changbaishan ash and the Quaternary widespread ash around Japan illustrates that Changbaishan ash is a continuous composition from rhyolitic to trachytic and its ratio of FeOT to CaO is usually greater than 4, which can be used as a distinguishing identifier among worldwide contemporary eruptions.

  12. Distribution, geochemistry and age of the Millennium eruptives of Changbaishan volcano, Northeast China — A review

    NASA Astrophysics Data System (ADS)

    Sun, Chunqing; You, Haitao; Liu, Jiaqi; Li, Xin; Gao, Jinliang; Chen, Shuangshuang

    2014-06-01

    Large explosive volcanic eruptions generate extensive regional tephra deposits that provide favorable conditions for identifying the source of volcanoes, comparing the sedimentary strata of a region and determining their ages. The tephra layer, referred to as B-Tm, generated by the Millennium eruption of Changbaishan volcano, is widely distributed in Northeast China, Japan, D.P.R. Korea, and the nearby coastal area of Russia. It forms part of the widespread northeast Asian strata and is significant for establishing an isochronal stratigraphic framework. However, research on the temporal characterization and stratigraphic correlation of associated strata using this tephra layer is mainly concentrated in and near Japan. In northeastern China, this tephra layer is seldom seen and its application in stratigraphic correlations is even rarer. More importantly, the determination of accurate ages for both distal and proximal tephras has been debated, leading to controversy in discussions of its environmental impacts. Stratigraphic records from both distal and proximal Changbaishan ash show that this eruption generally occurred between 1,012 and 1,004 cal yr BP. Geochemical comparison between Changbaishan ash and the Quaternary widespread ash around Japan illustrates that Changbaishan ash is a continuous composition from rhyolitic to trachytic and its ratio of FeOT to CaO is usually greater than 4, which can be used as a distinguishing identifier among worldwide contemporary eruptions.

  13. Hippocampal Laminar Distribution of Tau Relates to Alzheimer's Disease and Age of Onset

    PubMed Central

    Seifan, Alon; Marder, Karen S.; Mez, Jesse; Noble, James M.; Cortes, Etty P.; Vonsattel, Jean Paul; Honig, Lawrence S.

    2015-01-01

    Background Cerebral deposition of phospho-tau in Alzheimer's disease (AD) occurs with varying patterns within hippocampus. Lamina-specific tau changes in AD may reflect trans-synaptic propagation of phospho-tau along neuroanatomical pathways. Objective To study patterns of tau deposition within inner (IML) and outer (OML) molecular layers of dentate gyrus and their clinical and neuropathological correlates. Methods 98 consecutive autopsied brains from the Columbia University Brain Bank were stained for phospho-tau using AT-8. Staining density was rated as High versus Low within IML and OML. Four patterns were observed among the 98 brains: High IML&OML, n = 44; High OML Only (n = 35); High IML Only (n = 5); and Low IML&OML (n = 14). Demographic, clinical, and neuropathological characteristics of these four groups were compared. Results High IML&OML subjects, versus High OML Only, were more likely to fulfill CERAD criteria for Definite AD (93% versus 66%, p < 0.01) and to have higher median Braak stage (6 versus 5, p < 0.01) and earlier mean age of onset (65.9 versus 73.7 y, p = 0.02), with similar symptom duration. Using logistic regression, the association between High IML&OML and AD remained significant after adjustment for demographics but not symptom duration. In the 70 subjects with Definite AD, High IML&OML was associated with younger age of onset (mean difference 3.7 years, 95%CI −6.7 to −0.7, p < 0.01), after adjustment for demographics and symptom duration. Conclusions Phospho-tau pathology, when prominent within both IML and OML, is associated with CERAD diagnosis of Definite AD and earlier age of onset in AD. Laminar patterns of tau deposition reflect regional involvements during disease course. PMID:25079799

  14. Kilauea summit overflows: Their ages and distribution in the Puna District, Hawai'i

    USGS Publications Warehouse

    Clague, D.A.; Hagstrum, J.T.; Beeson, M.H.; Champion, D.E.

    1999-01-01

    The tube-fed pahoehoe lava flows covering much of the northeast flank of Kilauea Volcano are named the 'Aila'au flows. Their eruption age, based on published and six new radiocarbon dates, is approximately AD 1445. The flows have distinctive paleomagnetic directions with steep inclinations (40??-50??) and easterly declinations (0??-10??E). The lava was transported ~40 km from the vent to the coast in long, large-diameter lava tubes; the longest tube (Kazumura Cave) reaches from near the summit to within several kilometers of the coast near Kaloli Point. The estimated volume of the 'Aila'au flow field is 5.2 ?? 0.8 km3, and the eruption that formed it probably lasted for approximately 50 years. Summit overflows from Kilauea may have been nearly continuous between approximately AD 1290 and 1470, during which time a series of shields formed at and around the summit. The 'Aila'au shield was either the youngest or the next to youngest in this series of shields. Site-mean paleomagnetic directions for lava flows underlying the 'Aila'au flows form only six groups. These older pahoehoe flows range in age from 2750 to 2200 years. Lava flows from most of these summit eruptions also reached the coast, but none appears as extensive as the 'Aila'au flow field. The chemistry of the melts erupted during each of these summit overflow events is remarkably similar, averaging approximately 6.3 wt.% MgO near the coast and 6.8 wt.% MgO near the summit. The present-day caldera probably formed more recently than the eruption that formed the 'Aila'au flows (estimated termination ca. AD 1470). The earliest explosive eruptions that formed the Keanakako'i Ash, which is stratigraphically above the 'Aila'au flows, cannot be older than this age.

  15. Radiation-Related Treatment Effects across the Age Spectrum: Differences and Similarities or What The Old and Young Can Learn From Each Other

    PubMed Central

    Krasin, Matthew J.; Constine, Louis S.; Friedman, Debra; Marks, Lawrence B.

    2010-01-01

    Radiation related effects in children and adults limit the delivery of effective radiation doses and result in long-term morbidity affecting function and quality of life. Improvements in our understanding of the etiology and biology of these effects, including the influence of clinical variables, dosimetric factors, and the underlying biologic processes has made treatment safer and more efficacious. However, the approach to studying and understanding these effects differs between children and adults. By using the pulmonary and skeletal organ systems as examples, comparisons are made across the age spectrum for radiation related effects including pneumonitis, pulmonary fibrosis, osteonecrosis and fracture. Methods for dosimetric analysis, incorporation of imaging and biology as well a length of follow-up are compared, contrasted and discussed for both organ systems in children and adults. Better understanding of each age specific approach and how it differs may improve our ability to study late effects of radiation across the ages PMID:19959028

  16. Impact of the Hapagea surpercontinental aggregation on American Cordilleras and the seafloor age distribution

    NASA Astrophysics Data System (ADS)

    Husson, L.; Conrad, C. P.

    2009-12-01

    The ongoing aggregation of Africa, Arabia, India and Australia onto Eurasia is forming a supercontinent that we refer to as Hapagea. Although not as large as the older Pangea and Rodinia, Hapageais nevertheless large enough to profoundly modify Cenozoic plate kinematics as it gradually becomes a hub apart from which American continents spread. The continuation of Atlantic spreading is carried out at the expense of the Pacific Ocean, forcing the Farallon / Nazca plates down into eastern Pacific subduction zones, despite the fact that this seafloor is theoretically too young and too buoyant to subduct efficiently. This process occurred later for South America, where the subduction of the Tethys buffered the impact of the Atlantic expansion, and earlier for North America where this configuration was never met. The implications of the current plate tectonics are multiple and include (i) increased compression on the western coasts of the Americas, leading to Cordillera formation in North America (Sevier and Laramide) and later in South America (Andean), (ii) the transition from a rectangular distribution of seafloor ages to a triangular distribution as westward progress of the Americas engulfs young Farallon/Nazca seafloor, and (iii) a decrease in the convective efficiency of mantle flow that results in decreased rates of lithospheric productionat ridges, a situation that is cyclically met during the Wilson cycle and diminishes both mantle heat flow and sea level. These results imply that mantle drag causes the Atlantic spread and dominates the force balance of the Earth’s lithospheric shell.

  17. Age distributions and dynamically changing hydrologic systems: Exploring topography-driven flow

    NASA Astrophysics Data System (ADS)

    Gomez, J. D.; Wilson, J. L.

    2013-03-01

    Natural systems are driven by dynamic forcings that change in time as well as space, behavior that is inherited by the system flow field and results in time-varying age distributions (ADs). This work presents a review of the mathematical tools and solution approaches used to model ADs in dynamic time-varying flow systems. A simple conceptual, numerical model is then used to explore the role of flow dynamics in ADs for topography-driven flow systems. This model is an analog for regional groundwater systems and hyporheic zones. This model demonstrates that relatively small fluctuations in the forcing, even though importantly affecting the flow in the system, can have minimal effects in ADs. However, as the intensity of fluctuation increases, still within the bounds observed in natural systems, ADs in shallow parts of the system become highly sensitive to dynamic flow conditions, leading to considerable changes in the moments and modality of the distributions with time. In particular, transient flow can lead to emergence of new modes in the AD, which would not be present under steady flow conditions. The discrepancy observed between ADs under steady and transient flow conditions is explained by enhancement of mixing due to temporal variations in the flow field. ADs in deeper parts of the system are characterized by multimodality and tend to be more stable over time even for large forcing fluctuations.

  18. The gender similarities hypothesis.

    PubMed

    Hyde, Janet Shibley

    2005-09-01

    The differences model, which argues that males and females are vastly different psychologically, dominates the popular media. Here, the author advances a very different view, the gender similarities hypothesis, which holds that males and females are similar on most, but not all, psychological variables. Results from a review of 46 meta-analyses support the gender similarities hypothesis. Gender differences can vary substantially in magnitude at different ages and depend on the context in which measurement occurs. Overinflated claims of gender differences carry substantial costs in areas such as the workplace and relationships. PMID:16173891

  19. The gender similarities hypothesis.

    PubMed

    Hyde, Janet Shibley

    2005-09-01

    The differences model, which argues that males and females are vastly different psychologically, dominates the popular media. Here, the author advances a very different view, the gender similarities hypothesis, which holds that males and females are similar on most, but not all, psychological variables. Results from a review of 46 meta-analyses support the gender similarities hypothesis. Gender differences can vary substantially in magnitude at different ages and depend on the context in which measurement occurs. Overinflated claims of gender differences carry substantial costs in areas such as the workplace and relationships.

  20. Ground water age and nitrate distribution within a glacial aquifer beneath a thick unsaturated zone

    USGS Publications Warehouse

    Johnston, C.T.; Cook, P.G.; Frape, S.K.; Plummer, L.N.; Busenberg, E.; Blackport, R.J.

    1998-01-01

    The impact on ground water quality from increasing fertilizer application rates over the past 40 years is evaluated within a glacial aquifer system beneath a thick unsaturated zone. Ground water ages within the aquifer could not be accurately determined from the measured distribution of 3H and as a result, chlorofluorocarbon (CFC) and 3H/3He dating techniques were applied. Beneath a 25 m thick unsaturated zone, ground water ages based on CFC-11 concentrations were greater than 3H/3He ground water ages by 6 to 10 years, due to the time lag associated with the diffusion of CFCs through the unsaturated zone. Using the corrected CFC-11 and 3H/3He ground water ages and the estimated travel time of 3H within the unsaturated zone, the approximate position of ground water recharged since the mid-1960s was determined. Nitrate concentrations within post mid-1960s recharge were generally elevated and near or above the drinking water limit of 10 mg-N/L. In comparison, pre mid-1960s recharge had nitrate concentrations <2.5 mg-N/L. The elevated NO3- concentrations in post mid-1960s recharge are attributed mainly to increasing fertilizer application rates between 1970 and the mid- to late 1980s. Anaerobic conditions suitable for denitrification are present within pre mid-1960s recharge indicating that removal of DO is a slow process taking tens of years. Over the next 10 to 20 years, nitrate concentrations at municipal well fields that are currently capturing aerobic ground water recharged near the mid-1960s are expected to increase because of the higher fertilizer application rates beginning in the 1970s and 1980s.The impact on ground water quality from increasing fertilizer application rates over the past 40 years is evaluated within a glacial aquifer system beneath a thick unsaturated zone. Beneath a 25 m thick unsaturated zone, ground water ages based on CFC-11 concentrations were greater than 3H/3He ground water ages by 6 to 10 years, due to the time lag associated with the

  1. A Bayesian Modeling Approach for Estimation of a Shape-Free Groundwater Age Distribution using Multiple Tracers

    DOE PAGES

    Massoudieh, Arash; Visser, Ate; Sharifi, Soroosh; Broers, Hans Peter

    2013-10-15

    The mixing of groundwaters with different ages in aquifers, groundwater age is more appropriately represented by a distribution rather than a scalar number. To infer a groundwater age distribution from environmental tracers, a mathematical form is often assumed for the shape of the distribution and the parameters of the mathematical distribution are estimated using deterministic or stochastic inverse methods. We found that the prescription of the mathematical form limits the exploration of the age distribution to the shapes that can be described by the selected distribution. In this paper, the use of freeform histograms as groundwater age distributions is evaluated.more » A Bayesian Markov Chain Monte Carlo approach is used to estimate the fraction of groundwater in each histogram bin. This method was able to capture the shape of a hypothetical gamma distribution from the concentrations of four age tracers. The number of bins that can be considered in this approach is limited based on the number of tracers available. The histogram method was also tested on tracer data sets from Holten (The Netherlands; 3H, 3He, 85Kr, 39Ar) and the La Selva Biological Station (Costa-Rica; SF 6, CFCs, 3H, 4He and 14C), and compared to a number of mathematical forms. According to standard Bayesian measures of model goodness, the best mathematical distribution performs better than the histogram distributions in terms of the ability to capture the observed tracer data relative to their complexity. Among the histogram distributions, the four bin histogram performs better in most of the cases. The Monte Carlo simulations showed strong correlations in the posterior estimates of bin contributions, indicating that these bins cannot be well constrained using the available age tracers. The fact that mathematical forms overall perform better than the freeform histogram does not undermine the benefit of the freeform approach, especially for the cases where a larger amount of observed data is

  2. A Bayesian Modeling Approach for Estimation of a Shape-Free Groundwater Age Distribution using Multiple Tracers

    SciTech Connect

    Massoudieh, Arash; Visser, Ate; Sharifi, Soroosh; Broers, Hans Peter

    2013-10-15

    The mixing of groundwaters with different ages in aquifers, groundwater age is more appropriately represented by a distribution rather than a scalar number. To infer a groundwater age distribution from environmental tracers, a mathematical form is often assumed for the shape of the distribution and the parameters of the mathematical distribution are estimated using deterministic or stochastic inverse methods. We found that the prescription of the mathematical form limits the exploration of the age distribution to the shapes that can be described by the selected distribution. In this paper, the use of freeform histograms as groundwater age distributions is evaluated. A Bayesian Markov Chain Monte Carlo approach is used to estimate the fraction of groundwater in each histogram bin. This method was able to capture the shape of a hypothetical gamma distribution from the concentrations of four age tracers. The number of bins that can be considered in this approach is limited based on the number of tracers available. The histogram method was also tested on tracer data sets from Holten (The Netherlands; 3H, 3He, 85Kr, 39Ar) and the La Selva Biological Station (Costa-Rica; SF 6, CFCs, 3H, 4He and 14C), and compared to a number of mathematical forms. According to standard Bayesian measures of model goodness, the best mathematical distribution performs better than the histogram distributions in terms of the ability to capture the observed tracer data relative to their complexity. Among the histogram distributions, the four bin histogram performs better in most of the cases. The Monte Carlo simulations showed strong correlations in the posterior estimates of bin contributions, indicating that these bins cannot be well constrained using the available age tracers. The fact that mathematical forms overall perform better than the freeform histogram does not undermine the benefit of the

  3. Immunity in young adult survivors of childhood leukemia is similar to the elderly rather than age-matched controls: Role of cytomegalovirus.

    PubMed

    Azanan, Mohamad Shafiq; Abdullah, Noor Kamila; Chua, Ling Ling; Lum, Su Han; Abdul Ghafar, Sayyidatul Syahirah; Kamarulzaman, Adeeba; Kamaruzzaman, Shahrul; Lewin, Sharon R; Woo, Yin Ling; Ariffin, Hany; Rajasuriar, Reena

    2016-07-01

    Many treatment complications that occur late in childhood cancer survivors resemble age-related comorbidities observed in the elderly. An immune phenotype characterized by increased immune activation, systemic inflammation, and accumulation of late-differentiated memory CD57(+) CD28(-) T cells has been associated with comorbidities in the elderly. Here, we explored if this phenotype was present in young adult leukemia survivors following an average of 19 years from chemotherapy and/or radiotherapy completion, and compared this with that in age-matched controls. We found that markers of systemic inflammation-IL-6 and human C-reactive protein and immune activation-CD38 and HLA-DR on T cells, soluble CD (sCD)163 from monocytes and macrophages-were increased in survivors compared to controls. T-cell responses specific to cytomegalovirus (CMV) were also increased in survivors compared to controls while CMV IgG levels in survivors were comparable to levels measured in the elderly (>50years) and correlated with IL-6, human C-reactive protein, sCD163, and CD57(+) CD28(-) memory T cells. Immune activation and inflammation markers correlated poorly with prior chemotherapy and radiotherapy exposure. These data suggest that CMV infection/reactivation is strongly correlated with the immunological phenotype seen in young childhood leukemia survivors and these changes may be associated with the early onset of age-related comorbidities in this group. PMID:27129782

  4. Patterns and age distribution of ground-water flow to streams

    USGS Publications Warehouse

    Modica, E.; Reilly, T.E.; Pollock, D.W.

    1997-01-01

    Simulations of ground-water flow in a generic aquifer system were made to characterize the topology of ground-water flow in the stream subsystem and to evaluate its relation to deeper ground-water flow. The flow models are patterned after hydraulic characteristics of aquifers of the Atlantic Coastal Plain and are based on numerical solutions to three-dimensional, steady-state, unconfined flow. The models were used to evaluate the effects of aquifer horizontal-to-vertical hydraulic conductivity ratios, aquifer thickness, and areal recharge rates on flow in the stream subsystem. A particle tracker was used to determine flow paths in a stream subsystem, to establish the relation between ground-water seepage to points along a simulated stream and its source area of flow, and to determine ground-water residence time in stream subsystems. In a geometrically simple aquifer system with accretion, the source area of flow to streams resembles an elongated ellipse that tapers in the downgradient direction. Increased recharge causes an expansion of the stream subsystem. The source area of flow to the stream expands predominantly toward the stream headwaters. Baseflow gain is also increased along the reach of the stream. A thin aquifer restricts ground-water flow and causes the source area of flow to expand near stream headwaters and also shifts the start-of-flow to the drainage basin divide. Increased aquifer anisotropy causes a lateral expansion of the source area of flow to streams. Ground-water seepage to the stream channel originates both from near- and far-recharge locations. The range in the lengths of flow paths that terminate at a point on a stream increase in the downstream direction. Consequently, the age distribution of ground water that seeps into the stream is skewed progressively older with distance downstream. Base flow ia an integration of ground water with varying age and potentially different water quality, depending on the source within the drainage basin

  5. NewAge: a semi-distributed hydrological model as a dynamical system, and something more.

    NASA Astrophysics Data System (ADS)

    Rigon, Riccardo; Franceschi, Silvia; Antonello, Andrea; Endrizzi, Stefano; Formetta, Giuseppe

    2010-05-01

    We describe and analyse the performances of the semi-distributed hydrological model NewAGE. This model itself is made-up of five main parts: the radiation budget estimation, the snow modelling, the evapotranspiration part, the hillslope runoff budget and the runoff aggregation in the river network, and finally the flood propagation. The model concept is based on the idea the elementary units are the hillslopes for each one the model gives the estimates of the prognostic simulated variables (one estimate for variable). Each "hillslope" does not need to coincide to the real hillslope, and can actually cover a small basin, up to some square kilometres. It constitutes the elementary "grid" element of the model. Each "hillslope" is connected to the others by the channel network. In turn, this is represented by an oriented graph, whose links are numbered through a generalisation of the Pfafstetter ordering. The topological partition of the basin is performed by a proper set of tools in JGrass. The mass budget for each hillslope is performed according to a suitable modification of Duffy (1996) dynamical model of hillslope runoff. Discharge in each link of the river network is evaluated according to Cuencas (2005). Radiation is calculated accounting for the sub-hillslope-variability in accord to a suitable scheme described in this contribution. Evapotranspiration estimation uses the Penman-Monteith formula, and includes hillslope variability in land use, soil cover and hydrological state. Flood wave propagation for the main streams can be estimated with a solver of the 1D de Saint Venant equation. Snow is modelled by a custom implementation of the Utah Energy Balance concepts. This model can simulate all the parts of the hydrological cycle, but besides being also a model of the physical processes, it also implements the infrastructure dealing with human works and reservoirs. These modelling parts are supported by appropriate ancillary modules for the treatment of the

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

    USGS Publications Warehouse

    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

  7. Age-dependence of the optomechanical responses of ex vivo human lenses from India and the USA, and the force required to produce these in a lens stretcher: the similarity to in vivo disaccommodation.

    PubMed

    Augusteyn, Robert C; Mohamed, Ashik; Nankivil, Derek; Veerendranath, Pesala; Arrieta, Esdras; Taneja, Mukesh; Manns, Fabrice; Ho, Arthur; Parel, Jean-Marie

    2011-07-15

    The purpose of this study was to study the age-dependence of the optomechanical properties of human lenses during simulated disaccommodation in a mechanical lens stretcher, designed to determine accommodative forces as a function of stretch distance, to compare the results with in vivo disaccommodation and to examine whether differences exist between eyes harvested in the USA and India. Postmortem human eyes obtained in the USA (n=46, age=6-83 years) and India (n=91, age=1 day-85 years) were mounted in an optomechanical lens stretching system and dissected to expose the lens complete with its accommodating framework, including zonules, ciliary body, anterior vitreous and a segmented rim of sclera. Disaccommodation was simulated through radial stretching of the sectioned globe by 2mm in increments of 0.25 mm. The load, inner ciliary ring diameter, lens equatorial diameter, central thickness and power were measured at each step. Changes in these parameters were examined as a function of age, as were the dimension/load and power/load responses. Unstretched lens diameter and thickness increased over the whole age range examined and were indistinguishable from those of in vivo lenses as well as those of in vitro lenses freed from zonular attachments. Stretching increased the diameter and decreased the thickness in all lenses examined but the amount of change decreased with age. Unstretched lens power decreased with age and the accommodative amplitude decreased to zero by age 45-50. The load required to produce maximum stretch was independent of age (median 80 mN) whereas the change in lens diameter and power per unit load decreased significantly with age. The age related changes in the properties of human lenses, as observed in the lens stretching device, are similar to those observed in vivo and are consistent with the classical Helmholtz theory of accommodation. The response of lens diameter and power to disaccommodative (stretching) forces decreases with age

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

    PubMed Central

    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. Crater size-frequency distribution measurements and age of the Compton-Belkovich Volcanic Complex

    NASA Astrophysics Data System (ADS)

    Shirley, K. A.; Zanetti, M.; Jolliff, B.; van der Bogert, C. H.; Hiesinger, H.

    2016-07-01

    The Compton-Belkovich Volcanic Complex (CBVC) is a 25 × 35 km feature on the lunar farside marked by elevated topography, high albedo, high thorium concentration, and high silica content. Morphologies indicate that the complex is volcanic in origin and compositions indicate that it represents rare silicic volcanism on the Moon. Constraining the timing of silicic volcanism at the complex is necessary to better understand the development of evolved magmas and when they were active on the lunar surface. We employ image analysis and crater size-frequency distribution (CSFD) measurements on several locations within the complex and at surrounding impact craters, Hayn (87 km diameter), and Compton (160 km diameter), to determine relative and absolute model ages of regional events. Using CSFD measurements, we establish a chronology dating regional resurfacing events and the earliest possible onset of CBVC volcanism at ∼3.8 Ga, the formation of Compton Crater at 3.6 Ga, likely resurfacing by volcanism at the CBVC at ∼3.5 Ga, and the formation of Hayn Crater at ∼1 Ga. For the CBVC, we find the most consistent results are obtained using craters larger than 300 m in diameter; the small crater population is affected by their approach to an equilibrium condition and by the physical properties of regolith at the CBVC.

  10. Recent changes in earnings distributions in the United States: age and cohort effects.

    PubMed

    Utendorf, K R

    1999-01-01

    In this article, the author uses large, Social Security administrative data sets to examine changes in earnings distributions in the United States over the 1980s through the mid-1990s. Because the earnings information contained in these data sets comes directly from the W-2 forms field by employers, self-reporting errors and top-coding problems, common in other data used for this type of analysis, are minimized. Previous research has documented an increase in overall earnings inequality during the 1970s and the 1980s. The author finds that this upward trend in overall earnings inequality continues into the mid-1990s, despite a period of nearly constant or slightly decreasing earnings inequality from 1988 through 1992. The data also suggest that between-group earnings inequality, whether dividing the sample into groups by age group or by birth cohort, is increasing. Despite the increase in between-group earnings inequality over the period examined, however, within-group earnings inequality remains by far the largest contributor to overall earnings inequality.

  11. [Relation between cardiorespiratory indicators, blood lipids, and the amount and distribution of adipose tissue in middle-aged men].

    PubMed

    Parízková, J; Vĕtvicka, J; Pousek, L; Liska, O

    1995-06-28

    BACKGROUND. In middle-aged and elderly men the cardiovascular mortality in this country is still relatively high. The objective of the presented work was therefore the validation of simple parameters of fat deposition as a risk factor in order to select subjects at risk where preventive measures are called for. METHODS AND RESULTS. In 68 men aged 43.8 +/- 7.4 years from a sample of managers of a Prague bank the case-history we evaluated, as well as a basic physical examination, a loading test on a bicycle ergometer (performance evaluated in W/kg body weight or lean body mass) and ECG; serum lipids were examined (total and HDL-cholesterol, triacyglycerols), the body mass index (BMI), the ratio of depot fat (by evaluation of 10 skinfolds measured by means of a caliper) and the distribution of body fat (indices relating either only the subscapular and tricipital skinfold or all skinfolds on the trunk to all skinfolds on the extremities, and the waist/hip ratio). The basic physical examination did not reveal any serious acute diseases. Mean BMI values (26.7 +/- 3.4 kg/m2) and body fat ratio (20.8 +/- 4.2%) were higher than standard values. 24.1% of the men were obese, the W/H ratio was 0.9 +/- 0.1 but this index, similarly as the other mentioned indices, were elevated, indicating risk. The mean values of the heart rate and blood pressure at rest and after a load were normal, however 11.5% of the men had an elevated diastolic pressure after a load and a similar percentage of men manifested during a load certain signs of myocardial ischaemia. The prevalence of hypertension according to WHO criteria was 9.6%. On average, however, the physical performance (W/kg of the total body weight or lean body mass) was 108% of the Czech standard assessed previously within the framework of the International Biological Programme. The total cholesterol was 5.35 +/- 1.04, HDL 1.11 +/- 0.19, total triacylglycerols 1.81 +/- 0.77 mmol/l. The ratio of total and HDL cholesterol was 4.9 +/- 1

  12. Effects of topography, soil type and forest age on the frequency and size distribution of canopy gap disturbances in a tropical forest

    NASA Astrophysics Data System (ADS)

    Lobo, E.; Dalling, J. W.

    2013-11-01

    Treefall gaps are the major source of disturbance in most tropical forests. The frequency and size of these gaps have important implications for forest ecosystem processes as they can influence the functional trait distribution of tree communities, stand-level aboveground biomass and productivity. However, we still know little about the relative importance of environmental drivers of gap disturbance regimes because existing studies vary greatly in criteria used for defining gaps, in the spatial extent of the study area, and the spatial resolution of canopy height measurements. Here we use lidar (light detecting and ranging) to explore how forest age, topography and soil type affect canopy disturbance patterns across a 1500 ha tropical forest landscape in central Panama. We characterize disturbance based on the frequency distribution of gap sizes (the "gap size distribution"), and the area of the forest affected by gaps (the "gap area fraction"). We found that slope and forest age had significant effects on the gap size distribution, with a higher frequency of large gaps associated with old-growth forests and more gentle slopes. Slope and forest age had similar effects on the gap area fraction, however gap area fraction was also affected by soil type and by aspect. We conclude that variation in disturbance patterns across the landscape can be linked to factors that act at the fine scale (such as aspect or slope), and factors that show heterogeneity at coarser scales (such as forest age or soil type). Awareness of the role of different environmental factors influencing gap formation can help scale up the impacts of canopy disturbance on forest communities measured at the plot scale to landscape and regional scales.

  13. Effects of topography, soil type and forest age on the frequency and size distribution of canopy gap disturbances in a tropical forest

    NASA Astrophysics Data System (ADS)

    Lobo, E.; Dalling, J. W.

    2013-04-01

    Treefall gaps are the major source of disturbance in most tropical forests. The frequency and size of these gaps have important implications for forest ecosystem processes as they can influence the functional trait distribution of tree communities, stand-level above-ground biomass and productivity. However, we still know little about the relative importance of environmental drivers of gap disturbance regimes because existing studies vary greatly in criteria used for defining gaps, in the spatial extent of the study area, and the spatial resolution of canopy height measurements. Here we use LiDAR (light detecting and ranging) to explore how forest age, topography and soil type affect canopy disturbance patterns across a 1500 ha tropical forest landscape in central Panama. We characterize disturbance based on the frequency distribution of gap sizes (the "gap size distribution"), and the area of the forest affected by gaps (the "gap area fraction"). We found that slope and forest age had significant effects on the gap size distribution, with a higher frequency of large gaps associated with old-growth forests and more gentle slopes. Slope and forest age had similar effects on the gap area fraction, however gap area fraction was also affected by soil type and by aspect. We conclude that variation in disturbance patterns across the landscape can be linked to factors that act at the fine scale (such as aspect or slope), and factors that show heterogeneity at coarser scales (such as forest age or soil type). Awareness of the role of different environmental factors influencing gap formation can help scale-up the impacts of canopy disturbance on forest communities measured at the plot scale to landscape and regional scales.

  14. Age-related prevalence, intensity and frequency distribution of gastrointestinal helminth infection in urban slum children from Kuala Lumpur, Malaysia.

    PubMed

    Bundy, D A; Kan, S P; Rose, R

    1988-01-01

    The gastrointestinal helminth infection status of 1574 children living in a slum area of Kuala Lumpur, Malaysia was assessed by quantitative coprology. Almost two-thirds were infected with Trichuris trichiura, 49.6% with Ascaris lumbricoides, and 5.3% with hookworm. Infection prevalence rose rapidly to a stable asymptote at 7 years of age, and the age-intensity profile was convex with maximal values in the 5-10 year age classes. This pattern was the same for males and females, but differed markedly between different ethnic groups. The frequency distributions of A. lumbricoides and T. trichiura were highly overdispersed (k values were 0.21 and 0.27, respectively), and age-dependent over the 0-8 year age classes. This suggests that the force of infection with these nematodes is lower in infants than in older children.

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

    PubMed Central

    Guarner-Lans, Verónica; Soria-Castro, Elizabeth; Torrico-Lavayen, Rocío; Patrón-Soberano, Araceli; Carvajal-Aguilera, Karla G.; Castrejón-Tellez, Vicente; Rubio-Ruiz, María Esther

    2016-01-01

    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. PMID:27293881

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

    PubMed

    Guarner-Lans, Verónica; Soria-Castro, Elizabeth; Torrico-Lavayen, Rocío; Patrón-Soberano, Araceli; Carvajal-Aguilera, Karla G; Castrejón-Tellez, Vicente; Rubio-Ruiz, María Esther

    2016-01-01

    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. PMID:27293881

  17. RELN-expressing Neuron Density in Layer I of the Superior Temporal Lobe is Similar in Human Brains with Autism and in Age-Matched Controls

    PubMed Central

    Camacho, Jasmin; Ejaz, Ehsan; Ariza, Jeanelle; Noctor, Stephen C.; Martínez-Cerdeño, Verónica

    2015-01-01

    Reelin protein (RELN) level is reduced in the cerebral cortex and cerebellum of subjects with autism. RELN is synthesized and secreted by a subpopulation of neurons in the developing cerebral cortex termed Cajal-Retzius (CR) cells. These cells are abundant in the marginal zone during cortical development, many die after development is complete, but a small population persists into adulthood. In adult brains, RELN is secreted by the surviving CR cells, by a subset of GABAergic interneurons in layer I, and by pyramidal cells and GABAergic interneurons in deeper cortical layers. It is widely believed that decreased RELN in layer I of the cerebral cortex of subjects with autism may result from a decrease in the density of RELN expressing neurons in layer I; however, this hypothesis has not been tested. We examined RELN expression in layer I of the adult human cortex and found that 70% of cells express RELN in both control and autistic subjects. We quantified the density of neurons in layer I of the superior temporal cortex of subjects with autism and age-matched control subjects. Our data show that there is no change in the density of neurons in layer I of the cortex of subjects with autism, and therefore suggest that reduced RELN expression in the cerebral cortex of subjects with autism is not a consequence of decreased numbers of RELN-expressing neurons in layer I. Instead reduced RELN may result from abnormal RELN processing, or a decrease in the number of other RELN-expressing neuronal cell types. PMID:25067827

  18. Cyclic intensive light exposure induces retinal lesions similar to age-related macular degeneration in APPswe/PS1 bigenic mice

    PubMed Central

    2012-01-01

    Background Intensive light exposure and beta-amyloid (Aβ) aggregates have been known as a risk factor for macular degeneration and an important component in the pathologic drusen structure involved in this disorder, respectively. However, it is unknown whether Aβ deposition mediates or exacerbates light exposure-induced pathogenesis of macular degeneration. Several studies including the one from us already showed accumulation of Aβ deposits in the retina in Alzheimer's transgenic mice. Using histopathological analysis combined with electroretinographic functional assessment, we investigated the effects of cyclic intensive light exposure (CILE) on the architecture of retina and related function in the APPswe/PS1bigenic mouse. Results Histopathological analysis has found significant loss of outer nuclear layer/photoreceptor outer segment and outer plexiform layer along with abnormal hypo- and hyper-pigmentation in the retinal pigment epithelium (RPE), remarkable choroidal neovascularization (CNV), and exaggerated neuroinflammatory responses in the outer retina of APPswe/PS1 bigenic mice following cyclic intensive light exposure (CILE), whereas controls remained little change contrasted with age-matched non-transgenic littermates. CILE-induced degenerative changes in RPE are further confirmed by transmission electron microcopy and manifest as formation of basal laminar deposits, irregular thickening of Bruch's membrane (BrM), deposition of outer collagenous layer (OCL) in the subretinal space, and vacuolation in the RPE. Immunofluorescence microscopy reveals drusenoid Aβ deposits in RPE as well as neovessels attached which are associated with disruption of RPE integrity and provoked neuroinflammatory response as indicated by markedly increased retinal infiltration of microglia. Moreover, both immunohistochemistry and Western blots detect an induction of vascular endothelial growth factor (VEGF) in RPE, which corroborates increased CNV in the outer retina in the

  19. Age-related changes in the distributions of depressive symptom items in the general population: a cross-sectional study using the exponential distribution model.

    PubMed

    Tomitaka, Shinichiro; Kawasaki, Yohei; Ide, Kazuki; Yamada, Hiroshi; Furukawa, Toshiaki A; Ono, Yutaka

    2016-01-01

    Background. Previous research has reported inconsistent evidence of the trajectory of depressive symptoms across the adult lifespan. We investigated how the distributions of each item score change with age and determined whether the trajectory of depressive symptoms varied with the scoring methods of the questionnaire. Methods. We analyzed data collected from 21,040 subjects who participated in the national survey in Japan. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale (CES-D). The CES-D has 20 items, each of which is scored in four grades of "rarely," "some," "much," and "most of the time." We used the exponential distribution model which fits the distributions of 16 negative symptom items of CES-D, with the probabilities of "some," "much," "most," and "rarely" expressed as P, Pr, Pr (2), and 1 - P × (r (2) + r + 1). Results. The distributions of the responses to 16 negative symptom items followed the common exponential model across all age groups. The mean of the estimated parameter r of 16 negative items showed a U-shape pattern, being high during 12-29 years, remaining low during 30-50 years, and then increasing again over 60 years. The trajectory of depressive symptom scores simulating the binary method was different from that of the empirical scores using the Likert method. Conclusions. Our findings show that the increase in the depressive symptoms score during older age is based on the increase of the parameter r. The differences in the scoring method may contribute to the different age-related patterns across the adult lifespan. PMID:26788427

  20. Distribution of age-related thymulin titres in normal subjects through the course of life

    PubMed Central

    Consolini, R; Legitimo, A; Calleri, A; Milani, M

    2000-01-01

    The thymus has a dominant immunological role in utero and in early childhood, being a primary source of T lymphopoiesis, and its investigation may be particularly relevant for the immunological study of paediatric patients. Thymulin, a nonapeptide secreted by the thymus, is an essential hormone for T lymphocyte differentiation and function. As thymulin values in the normal population have not been well documented, especially for children under the age of 1 year, we detail thymic endocrine function by presenting age-related plasma thymulin levels in a large series (n = 93) of healthy individuals, ranging from birth to old age. We demonstrate that thymulin is already detectable at birth; it then gradually increases with age, reaching the highest level in children aged 5–10 years. Starting at adolescence, thymulin titres gradually start to fall, reaching the lowest value at 36 years of age and remaining steady until 80 years (the oldest person tested). PMID:10971509

  1. Multivariate Hypergeometric Similarity Measure

    PubMed Central

    Kaddi, Chanchala D.; Parry, R. Mitchell; Wang, May D.

    2016-01-01

    We propose a similarity measure based on the multivariate hypergeometric distribution for the pairwise comparison of images and data vectors. The formulation and performance of the proposed measure are compared with other similarity measures using synthetic data. A method of piecewise approximation is also implemented to facilitate application of the proposed measure to large samples. Example applications of the proposed similarity measure are presented using mass spectrometry imaging data and gene expression microarray data. Results from synthetic and biological data indicate that the proposed measure is capable of providing meaningful discrimination between samples, and that it can be a useful tool for identifying potentially related samples in large-scale biological data sets. PMID:24407308

  2. Some bounds in classes of {open_quotes}aging{close_quotes} distributions

    SciTech Connect

    Kotlyar, V.Yu.

    1995-03-01

    Reliability of technical systems is closely linked with {open_quotes}aging{close_quotes} properties of the components. So-called monotone systems whose components have certain aging characteristics are of considerable importance in this field of research. Efficient bounds of reliability, mean time to failure, and other parameters can be obtained for such systems. The bounds in literature were obtained under the least restrictive assumptions on aging. In this paper, we generalize some results of literature to the case of even more general aging principles, specifically, when the system components are HNBUE, HNWUE, NBAFR, NWAFR in terms of their reliability properties. We start with a definition of these properties.

  3. The age, growth, and bathymetric distribution of Reighard's chub, Leucichthys reighardi koelz, in Lake Michigan

    USGS Publications Warehouse

    1943-01-01

    The females were always strongly dominant in the samples except during May and June 1931 and May 1932 when the sexes occurred in about equal numbers. The relative abundance of the sexes did not change materially in age-groups II to V. There were no males assigned to age-groups VI and VII.

  4. Changes in the mineral density distribution in human bone with age: image analysis using backscattered electrons in the SEM.

    PubMed

    Reid, S A; Boyde, A

    1987-02-01

    We report a study to test the feasibility of studying mineral density distributions in bone using the backscattered electron signal in scanning electron microscopy. Samples were human sixth ribs ranging in age from 8 weeks to 59 years, embedded in polymethylmethacrylate (PMMA), cut, polished, and carbon coated. The proportions of pixels falling in a uniform set of gray level slices of the BSE signal were determined using a microcomputer-based image analysis system interfaced directly to the SEM. The amount of high-density bone gradually increased with age at the expense of low-density bone, and there was an associated compression of the range of the mineral density distribution. Age-related differences were noted between the density distributions in the outer and inner rib cortices. The distribution in the inner cortex in neonates was influenced by the inclusion of densely mineralized endochondral bone and cartilage trabeculae formed at the growth cartilage zone. In adults it appeared that greater bone turnover occurred in the outer cortex, perhaps reflecting a differential mechanical loading across the rib. The technique enabled rapid, unbiased discrimination between the bone of neonates, children, and adults. PMID:3455153

  5. Deep-sea scleractinian coral age and depth distributions in the northwest Atlantic for the last 225,000 years

    USGS Publications Warehouse

    Robinson, L.F.; Adkins, J.F.; Scheirer, D.S.; Fernandez, D.P.; Gagnon, A.; Waller, R.G.

    2007-01-01

    Deep-sea corals have grown for over 200,000 yrs on the New England Seamounts in the northwest Atlantic, and this paper describes their distribution both with respect to depth and time. Many thousands of fossil scleractinian corals were collected on a series of cruises from 2003-2005; by contrast, live ones were scarce. On these seamounts, the depth distribution of fossil Desmophyllum dianthus (Esper, 1794) is markedly different to that of the colonial scleractinian corals, extending 750 m deeper in the water column to a distinct cut-off at 2500 m. This cut-off is likely to be controlled by the maximum depth of a notch-shaped feature in the seamount morphology. The ages of D. dianthus corals as determined by U-series measurements range from modern to older than 200,000 yrs. The age distribution is not constant over time, and most corals have ages from the last glacial period. Within the glacial period, increases in coral population density at Muir and Manning Seamounts coincided with times at which large-scale ocean circulation changes have been documented in the deep North Atlantic. Ocean circulation changes have an effect on coral distributions, but the cause of the link is not known. ?? 2007 Rosenstiel School of Marine and Atmospheric Science of the University of Miami.

  6. Characterization and distribution of a maize cDNA encoding a peptide similar to the catalytic region of second messenger dependent protein kinases

    NASA Technical Reports Server (NTRS)

    Biermann, B.; Johnson, E. M.; Feldman, L. J.

    1990-01-01

    Maize (Zea mays) roots respond to a variety of environmental stimuli which are perceived by a specialized group of cells, the root cap. We are studying the transduction of extracellular signals by roots, particularly the role of protein kinases. Protein phosphorylation by kinases is an important step in many eukaryotic signal transduction pathways. As a first phase of this research we have isolated a cDNA encoding a maize protein similar to fungal and animal protein kinases known to be involved in the transduction of extracellular signals. The deduced sequence of this cDNA encodes a polypeptide containing amino acids corresponding to 33 out of 34 invariant or nearly invariant sequence features characteristic of protein kinase catalytic domains. The maize cDNA gene product is more closely related to the branch of serine/threonine protein kinase catalytic domains composed of the cyclic-nucleotide- and calcium-phospholipid-dependent subfamilies than to other protein kinases. Sequence identity is 35% or more between the deduced maize polypeptide and all members of this branch. The high structural similarity strongly suggests that catalytic activity of the encoded maize protein kinase may be regulated by second messengers, like that of all members of this branch whose regulation has been characterized. Northern hybridization with the maize cDNA clone shows a single 2400 base transcript at roughly similar levels in maize coleoptiles, root meristems, and the zone of root elongation, but the transcript is less abundant in mature leaves. In situ hybridization confirms the presence of the transcript in all regions of primary maize root tissue.

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

    PubMed Central

    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

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

    PubMed

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

    2016-01-01

    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

  9. [Dynamics of elements distribution in blood, depending on age, by example of Moscow Region residents].

    PubMed

    Yuvs, G G; Ignatova, T N; Anuchin, A M; Lebedeva, V L; Shilov, V V; Khapalyuk, A V

    2015-01-01

    Elemental status of a person determines the qualitative and quantitative content of chemical elements in the human body. This marker allows us to estimate the level of imbalance of chemical elements and therefore health risks. The method for simultaneous quantitative and qualitative analysis of 67 elements in biomaterials has been proposed. The detailed elemental analysis of whole blood samples of 1711 healthy people (age range 0-100 years) of Moscow Region has been performed. A number of patterns of age-related changes of the element status conditionally healthy people has been estimated. Na content in the samples increased with the age of the person. Presumably, this result reflects the studied populations nutrition disorders associated with immoderate consumption of table salt. The maximum content of Ca was observed in blood samples of people age range 0-20 years (66-69 mg/kg), the Ca content in the blood samples of people age range 26-85 years was significantly lower (59-62 mg/kg). The maximum decrease of Ca was detected in blood samples of people age range of 85-100 years (57-59 mg/kg). Thisreductionin the concentration of Ca, apparently due to age-related changes of Ca balance, correlates with decrease of bone mineral density and bone mass. Iron content decreased in the blood samples of people age range 10-100 years from 480 to 390 mg/kg. Selenium content in blood of people age range 0-25 years linearly increased, remained stable high in the blood of people age range 25-55 years (0,13-0,136 mg/kg) and then gradually decreased. A graph of As content dependence from a person's age is a mirror image of the graph of Se content dependence from a person's age, which is evidence of the antagonistic effects of these elements. Graphic changes in the content of rare earth elements Eu and Ho reflect the unidirectional trend of these elements accumulation. The maximum content of these elements was observed in blood samples of people age range of 25-65 years. Perhaps a

  10. [Dynamics of elements distribution in blood, depending on age, by example of Moscow Region residents].

    PubMed

    Yuvs, G G; Ignatova, T N; Anuchin, A M; Lebedeva, V L; Shilov, V V; Khapalyuk, A V

    2015-01-01

    Elemental status of a person determines the qualitative and quantitative content of chemical elements in the human body. This marker allows us to estimate the level of imbalance of chemical elements and therefore health risks. The method for simultaneous quantitative and qualitative analysis of 67 elements in biomaterials has been proposed. The detailed elemental analysis of whole blood samples of 1711 healthy people (age range 0-100 years) of Moscow Region has been performed. A number of patterns of age-related changes of the element status conditionally healthy people has been estimated. Na content in the samples increased with the age of the person. Presumably, this result reflects the studied populations nutrition disorders associated with immoderate consumption of table salt. The maximum content of Ca was observed in blood samples of people age range 0-20 years (66-69 mg/kg), the Ca content in the blood samples of people age range 26-85 years was significantly lower (59-62 mg/kg). The maximum decrease of Ca was detected in blood samples of people age range of 85-100 years (57-59 mg/kg). Thisreductionin the concentration of Ca, apparently due to age-related changes of Ca balance, correlates with decrease of bone mineral density and bone mass. Iron content decreased in the blood samples of people age range 10-100 years from 480 to 390 mg/kg. Selenium content in blood of people age range 0-25 years linearly increased, remained stable high in the blood of people age range 25-55 years (0,13-0,136 mg/kg) and then gradually decreased. A graph of As content dependence from a person's age is a mirror image of the graph of Se content dependence from a person's age, which is evidence of the antagonistic effects of these elements. Graphic changes in the content of rare earth elements Eu and Ho reflect the unidirectional trend of these elements accumulation. The maximum content of these elements was observed in blood samples of people age range of 25-65 years. Perhaps a

  11. The sex distribution of suicides by age in nations of the world.

    PubMed

    Lester, D

    1990-03-01

    The ratio of the male suicide rate to the female suicide rate for each age group in 31 nations of the world was found to be associated with the wealth of the nations. The male/female suicide rate ratio was lower in wealthier nations for older adults and higher in wealthier nations for youths. The male/female suicide rate ratio was associated over the nations among the younger age groups and also among the older age groups. These results suggest that the sex ratio may be differently determined in youths and in older adults.

  12. The occurrence and seasonal distribution of C50-C60-polyprenols and of C100-and similar long-chain polyprenols in leaves of plants.

    PubMed

    Chojnacki, T; Vogtman, T

    1984-01-01

    Large amounts of fully unsaturated, mainly-cis, higher isoprenoid alcohols consisting of 17-30 isoprene units were found in several plants of the Rosaceae family. They occur as mixtures of several prenologues with either C85 - or C100 - prenol dominating in the form of acetates. The highest level of these polyprenols (0.5-1.0% of wet weight) were found in Crataegus crus- galli , Cotonoaster lucida, Prunus serotina and Sorbus suecica (intermedia). Their content increased with increasing age of the leaves. The dynamics of this rise is different from that observed in the case of accumulation of free C50- C60 - prenols (up to 0.5% of wet weight) in leaves of various plant species.

  13. Synaptic distributions of GluA2 and PKMζ in the monkey dentate gyrus and their relationships with aging and memory.

    PubMed

    Hara, Yuko; Punsoni, Michael; Yuk, Frank; Park, C Sehwan; Janssen, William G M; Rapp, Peter R; Morrison, John H

    2012-05-23

    Rhesus monkeys provide a valuable model for studying the neurobiological basis of cognitive aging, because they are vulnerable to age-related memory decline in a manner similar to humans. In this study, young and aged monkeys were first tested on a well characterized recognition memory test (delayed nonmatching-to-sample; DNMS). Then, electron microscopic immunocytochemistry was performed to determine the subcellular localization of two proteins in the hippocampal dentate gyrus (DG): the GluA2 subunit of the glutamate AMPA receptor and the atypical protein kinase C ζ isoform (PKMζ). PKMζ promotes memory storage by regulating GluA2-containing AMPA receptor trafficking. Thus, we examined whether the distribution of GluA2 and PKMζ is altered with aging in DG axospinous synapses and whether it is coupled with memory deficits. Monkeys with faster DNMS task acquisition and more accurate recognition memory exhibited higher proportions of dendritic spines coexpressing GluA2 and PKMζ. These double-labeled spines had larger synapses, as measured by postsynaptic density area, than single-labeled and unlabeled spines. Within this population of double-labeled spines, aged monkeys compared with young expressed a lower density of synaptic GluA2 immunogold labeling, which correlated with lower recognition accuracy. Additionally, higher density of synaptic PKMζ labeling in double-labeled spines correlated with both faster task acquisition and better retention. Together, these findings suggest that age-related impairment in maintenance of GluA2 at the synapse in the primate hippocampus is coupled with memory deficits.

  14. An objective method to determine the probability distribution of the minimum apparent age of a sample of radio-isotopic dates

    NASA Astrophysics Data System (ADS)

    Ickert, R. B.; Mundil, R.

    2012-12-01

    points while being resistant to outliers, it utilizes the measurement uncertainties, and it does not require the assumption that any given cluster of data represents a single geological event. In brief, the technique generates a synthetic distribution from the input data by resampling with replacement (a bootstrap). Each resample is a random selection from a Gaussian distribution defined by the mean and uncertainty of the data point. For this distribution, the minimum value is calculated. This procedure is repeated many times (>1000) and a distribution of minimum values is generated, from which a confidence interval can be constructed. We demonstrate the application of this technique using natural and synthetic datasets, show the advantages and limitations, and relate it to other methods. We emphasize that this estimate remains strictly a minimum age - as with any other estimate that does not explicitly incorporate lag or residence time, it will not reflect a depositional age if the lag/residence time is larger than the uncertainty of the estimate. We recommend that this or similar techniques be considered by geochronologists. Ludwig, K.R., 2012. Isoplot 3.75, A geochronological toolkit for Microsoft Excel; Berkeley Geochronology Center Special Publication no. 5

  15. FUNDAMENTAL PARAMETERS AND SPECTRAL ENERGY DISTRIBUTIONS OF YOUNG AND FIELD AGE OBJECTS WITH MASSES SPANNING THE STELLAR TO PLANETARY REGIME

    SciTech Connect

    Filippazzo, Joseph C.; Rice, Emily L.; Faherty, Jacqueline; Cruz, Kelle L.; Van Gordon, Mollie M.; Looper, Dagny L.

    2015-09-10

    We combine optical, near-infrared, and mid-infrared spectra and photometry to construct expanded spectral energy distributions for 145 field age (>500 Myr) and 53 young (lower age estimate <500 Myr) ultracool dwarfs (M6-T9). This range of spectral types includes very low mass stars, brown dwarfs, and planetary mass objects, providing fundamental parameters across both the hydrogen and deuterium burning minimum masses for the largest sample assembled to date. A subsample of 29 objects have well constrained ages as probable members of a nearby young moving group. We use 182 parallaxes and 16 kinematic distances to determine precise bolometric luminosities (L{sub bol}) and radius estimates from evolutionary models give semi-empirical effective temperatures (T{sub eff}) for the full range of young and field age late-M, L, and T dwarfs. We construct age-sensitive relationships of luminosity, temperature, and absolute magnitude as functions of spectral type and absolute magnitude to disentangle the effects of degenerate physical parameters such as T{sub eff}, surface gravity, and clouds on spectral morphology. We report bolometric corrections in J for both field age and young objects and find differences of up to a magnitude for late-L dwarfs. Our correction in Ks shows a larger dispersion but not necessarily a different relationship for young and field age sequences. We also characterize the NIR–MIR reddening of low gravity L dwarfs and identify a systematically cooler T{sub eff} of up to 300 K from field age objects of the same spectral type and 400 K cooler from field age objects of the same M{sub H} magnitude.

  16. Monomeric Aβ1–40 and Aβ1–42 Peptides in Solution Adopt Very Similar Ramachandran Map Distributions That Closely Resemble Random Coil

    PubMed Central

    2016-01-01

    The pathogenesis of Alzheimer’s disease is characterized by the aggregation and fibrillation of amyloid peptides Aβ1–40 and Aβ1–42 into amyloid plaques. Despite strong potential therapeutic interest, the structural pathways associated with the conversion of monomeric Aβ peptides into oligomeric species remain largely unknown. In particular, the higher aggregation propensity and associated toxicity of Aβ1–42 compared to that of Aβ1–40 are poorly understood. To explore in detail the structural propensity of the monomeric Aβ1–40 and Aβ1–42 peptides in solution, we recorded a large set of nuclear magnetic resonance (NMR) parameters, including chemical shifts, nuclear Overhauser effects (NOEs), and J couplings. Systematic comparisons show that at neutral pH the Aβ1–40 and Aβ1–42 peptides populate almost indistinguishable coil-like conformations. Nuclear Overhauser effect spectra collected at very high resolution remove assignment ambiguities and show no long-range NOE contacts. Six sets of backbone J couplings (3JHNHα, 3JC′C′, 3JC′Hα, 1JHαCα, 2JNCα, and 1JNCα) recorded for Aβ1–40 were used as input for the recently developed MERA Ramachandran map analysis, yielding residue-specific backbone ϕ/ψ torsion angle distributions that closely resemble random coil distributions, the absence of a significantly elevated propensity for β-conformations in the C-terminal region of the peptide, and a small but distinct propensity for αL at K28. Our results suggest that the self-association of Aβ peptides into toxic oligomers is not driven by elevated propensities of the monomeric species to adopt β-strand-like conformations. Instead, the accelerated disappearance of Aβ NMR signals in D2O over H2O, particularly pronounced for Aβ1–42, suggests that intermolecular interactions between the hydrophobic regions of the peptide dominate the aggregation process. PMID:26780756

  17. Monomeric Aβ(1-40) and Aβ(1-42) Peptides in Solution Adopt Very Similar Ramachandran Map Distributions That Closely Resemble Random Coil.

    PubMed

    Roche, Julien; Shen, Yang; Lee, Jung Ho; Ying, Jinfa; Bax, Ad

    2016-02-01

    The pathogenesis of Alzheimer's disease is characterized by the aggregation and fibrillation of amyloid peptides Aβ(1-40) and Aβ(1-42) into amyloid plaques. Despite strong potential therapeutic interest, the structural pathways associated with the conversion of monomeric Aβ peptides into oligomeric species remain largely unknown. In particular, the higher aggregation propensity and associated toxicity of Aβ(1-42) compared to that of Aβ(1-40) are poorly understood. To explore in detail the structural propensity of the monomeric Aβ(1-40) and Aβ(1-42) peptides in solution, we recorded a large set of nuclear magnetic resonance (NMR) parameters, including chemical shifts, nuclear Overhauser effects (NOEs), and J couplings. Systematic comparisons show that at neutral pH the Aβ(1-40) and Aβ(1-42) peptides populate almost indistinguishable coil-like conformations. Nuclear Overhauser effect spectra collected at very high resolution remove assignment ambiguities and show no long-range NOE contacts. Six sets of backbone J couplings ((3)JHNHα, (3)JC'C', (3)JC'Hα, (1)JHαCα, (2)JNCα, and (1)JNCα) recorded for Aβ(1-40) were used as input for the recently developed MERA Ramachandran map analysis, yielding residue-specific backbone ϕ/ψ torsion angle distributions that closely resemble random coil distributions, the absence of a significantly elevated propensity for β-conformations in the C-terminal region of the peptide, and a small but distinct propensity for αL at K28. Our results suggest that the self-association of Aβ peptides into toxic oligomers is not driven by elevated propensities of the monomeric species to adopt β-strand-like conformations. Instead, the accelerated disappearance of Aβ NMR signals in D2O over H2O, particularly pronounced for Aβ(1-42), suggests that intermolecular interactions between the hydrophobic regions of the peptide dominate the aggregation process.

  18. Body size and fat distribution as predictors of coronary heart disease among middle-aged and older US men.

    PubMed

    Rimm, E B; Stampfer, M J; Giovannucci, E; Ascherio, A; Spiegelman, D; Colditz, G A; Willett, W C

    1995-06-15

    Obesity, android fat distribution, and other anthropometric measures have been associated with coronary heart disease in long-term prospective studies. However, fluctuations in weight due to age-related hormonal changes and changes in lifestyle practices may bias relative risk estimates over a long follow-up period. The authors prospectively studied the association between body mass index (BMI) (kg/m2), waist-to-hip ratio, and height as independent predictors of incident coronary heart disease in a 3-year prospective study among 29,122 US men aged 40-75 years in 1986. The authors documented 420 incident coronary events during the follow-up period. Body mass index, waist-to-hip ratio, short stature, and weight gain since age 21 were associated with an increased risk of coronary heart disease. Among men younger than 65, after adjusting for other coronary risk factors, the relative risk was 1.72 (95% confidence interval (CI) 1.10-2.69) for men with BMI of 25-28.9, 2.61 (95% CI 1.54-4.42) for BMI of 29.0-32.9, and 3.44 (95% CI 1.67-7.09) for obese men with BMI > or = 33 compared with lean men with BMI < 23.0. Among men > or = 65 years of age, the association between BMI and risk of coronary heart disease was much weaker. However, in this age group, the waist-to-hip ratio was a much stronger predictor of risk (relative risk = 2.76, 95% CI 1.22-6.23 between extreme quintiles). These results suggest that for younger men, obesity, independent of fat distribution, is a strong risk factor for coronary heart disease. For older men, measures of fat distribution may be better than body mass index at predicting risk of coronary disease.

  19. Assessing variation in skeletal production from surface death assemblages on the basis of age-frequency distributions

    NASA Astrophysics Data System (ADS)

    Tomasovych, Adam; Kidwell, Susan M.; Foygel Barber, Rina

    2015-04-01

    Age-frequency distributions of dead skeletal material that capture information on the elapsed time since death of individuals on the landscape or seabed provide decadal- to millennial-scale windows into the history of production and on the processes that lead to skeletal disintegration and burial. However, models quantifying the dynamics of skeletal loss assumed that skeletal production has been constant during accumulation of death assemblages. Here, we assess the joint effects of temporally-variable production and skeletal loss on the shape of postmortem age-frequency distributions. We show that the modes of such distributions will tend to be shifted to younger age cohorts relative to the true timing of past production pulses. This shift in the timing of a past production will be higher where loss rates are high and/or the rate of decline in production is slow. We apply the models combining the dynamic of loss and production to death assemblages with the deposit-feeding bivalve Nuculana taphria from the Southern California continental shelf, finding that (1) an onshore-offshore gradient in time averaging is dominated by a gradient in the timing of production, corresponding to the tracking of shallow-water habitats under a sea-level rise, and (2) model estimates of the timing of past production are in good agreement with an independent sea-level curve.

  20. Age-related changes in distribution of body weight on soles of feet for selected actions and postures.

    PubMed

    Yanagida, T; Asami, T

    1997-12-01

    We investigated age-related changes in the distribution of body weight on soles of feet in 878 healthy subjects ranging from 5 to 80 years of age. By modifying Morton's Staticometer, we constructed an instrument for measuring body-weight distribution over three areas of soles of the feet, the big toe (inner forefoot), the other four toes combined (outer forefoot) and the heels for both feet, thus a total of six areas. The weights in the six areas were recorded at the completion of nine selected actions and postures. We observed that for inhaling and exhaling standing postures, generally younger subjects had a ratio close to 1:2:3 for weights recorded for the inner toe:outer toes:heels as observed by Morton, but elderly subjects had a smaller value than 3 for the heel. The body-weight distribution tended to shift from heels to outer toes across age groups, which was more distinctly observed in women than in men.

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

    USGS Publications Warehouse

    Long, A.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.

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

    NASA Astrophysics Data System (ADS)

    Long, Andrew J.; Putnam, Larry D.

    2009-10-01

    SummaryConvolution 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.

  3. Human Gyrovirus Apoptin shows a similar subcellular distribution pattern and apoptosis induction as the chicken anaemia virus derived VP3/Apoptin

    PubMed Central

    Bullenkamp, J; Cole, D; Malik, F; Alkhatabi, H; Kulasekararaj, A; Odell, E W; Farzaneh, F; Gäken, J; Tavassoli, M

    2012-01-01

    The chicken anaemia virus-derived protein Apoptin/VP3 (CAV-Apoptin) has the important ability to induce tumour-selective apoptosis in a variety of human cancer cells. Recently the first human Gyrovirus (HGyV) was isolated from a human skin swab. It shows significant structural and organisational resemblance to CAV and encodes a homologue of CAV-Apoptin/VP3. Using overlapping primers we constructed a synthetic human Gyrovirus Apoptin (HGyV-Apoptin) fused to green fluorescent protein in order to compare its apoptotic function in various human cancer cell lines to CAV-Apoptin. HGyV-Apoptin displayed a similar subcellular expression pattern as observed for CAV-Apoptin, marked by translocation to the nucleus of cancer cells, although it is predominantly located in the cytosol of normal human cells. Furthermore, expression of either HGyV-Apoptin or CAV-Apoptin in several cancer cell lines triggered apoptosis at comparable levels. These findings indicate a potential anti-cancer role for HGyV-Apoptin. PMID:22495351

  4. Alterations in the molecular weight distribution of proteins in rat brain synaptosomes during aging and centrophenoxine treatment of old rats.

    PubMed

    Nagy, K; Nagy, I

    1984-12-01

    Properly prepared membrane proteins of brain synaptosomes of 2-, 12- and 24-month-old CFY female rats were filtrated on a Sepharose 2B gel. The molecular weight distribution showed an age-dependence: there was a clear shift toward the higher molecular weights in the adult and old rats. The observed alterations reflect an increased cross-linking of the proteins during aging due most probably to the OH free radical damage of the cell components. Centrophenoxine treatment for 2 months reversed this phenomenon in the old animals: the high molecular weight fractions decreased and the lower ones increased in the treated animals as compared to the old, untreated rats. The results support the membrane hypothesis of aging and contribute to a better understanding of the biological effects of centrophenoxine.

  5. Relationship of oral cancer with age, sex, site distribution and habits.

    PubMed

    Patel, Mandakini Mansukh; Pandya, Amrish N

    2004-04-01

    Many studies are carried out regarding age incidence, tobacco smoking and sites of oral cancer, but in Gujarat tobacco chewing in form of Gutkha is more common than smoking and start during preteen years. Tobacco chewing causing chronic inflammation, submucous fibrosis and oral cancer. This study was conducted on 504 patients to find out if there is increasing incidence of oral cancer in lower age group and its relation with sex as well which site was commonly affected. There was statistically significant increase in oral cancer in lower age group, and anatomically anterior part of oral cavity showed involvement in 61.32% of cases. Though males were affected more but female cases were 25%. So tobacco chewing has got detrimental effect on oral cavity. PMID:16295466

  6. Molecular seasonal, age and gender distributions of Cryptosporidium in diarrhoeic Egyptians: distinct endemicity.

    PubMed

    El-Badry, A A; Al-Antably, A S A; Hassan, M A; Hanafy, N A; Abu-Sarea, E Y

    2015-12-01

    Cryptosporidiosis is a worldwide gastrointestinal disease caused by the protozoan Cryptosporidium parasite. It has a broad range of seasonal and age-related prevalence. We aimed to study the molecular prevalence and seasonality of Cryptosporidium over a period of 1 year in a cohort of Egyptian diarrhoeic patients. Stool samples were collected from 865 diarrhoeic patients attending outpatient clinics of Cairo University hospitals, from all age groups over a 12-month period, examined microscopically for faecal Cryptosporidium oocysts by the acid-fast staining method and for copro-DNA detection using nested polymerase chain reaction (nPCR) assays. PCR-positive samples were characterised molecularly by nPCR-restriction fragment length polymorphism (RFLP) to determine Cryptosporidium genotypes. Cryptosporidium copro-DNA was detected in 19.5% of the collected samples throughout the year, with a major peak in summer (August) and a small rise in spring (April). Infection was mainly C. hominis (95.8%) followed by C. parvum (3.0%), affecting all age groups, with predominance in the pre-school age group, and decrease with age. There were statistically significant associations between the detection of Cryptosporidium and season, diarrhoea, patient age and drinking water, while gender, contact with animals and presence of mucus in stool showed no association. Cryptosporidium in diarrhoeic Egyptians was of distinct endemicity, with the bi-model mostly influenced by population dynamics, with a clear high prevalence in pre-school children and predominating anthroponotic (C. hominis) transmission throughout the year. The obtained results highlight Cryptosporidium as a water contaminant and an important cause of health problems in Egypt, necessitating further studies of the risk factors. PMID:26440040

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

    USGS Publications Warehouse

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

  8. Changes in the divorce rate and age distribution in China since the 1980s.

    PubMed

    Zeng, Y; Wu, D

    1997-01-01

    "The divorce rate in China during the 1980s was much higher than before for a number of reasons. In order to understand this phenomenon, the authors will make a comparison between the divorce rates, and the age and duration of the marriage at the time of divorce in the early 1980s and in the late 1980s and early 1990s."

  9. The age, growth, and distribution of the longjaw cisco, Leucichthys alpenae Koelz, in Lake Michigan

    USGS Publications Warehouse

    Jobes, Frank W.

    1949-01-01

    The sex ratio was determined from 7,457 individuals taken in 1930–1932 and 373 of the 1923 and 1928 specimens whose ages were determined. The percentage of females was relatively low in May 1931 and relatively high in October, but in the other months it remained more or less constant. In 1932 the femal

  10. Age, Dose, and Time-Dependency of Plasma and Tissue Distribution of Deltamethrine in Immature Rats

    EPA Science Inventory

    The major objective of this project was to characterize the systemic disposition of the pyrethroid, deltamethrin (DLT), in immature rats, with emphasis on the age-dependence of target organ (brain) dosimetry. Postnatal day (PND) 10, 21, and 40 male Sprague-Dawley rats received 0...

  11. Delayed Adulthood, Delayed Desistance? Trends in the Age Distribution of Problem Behaviors

    ERIC Educational Resources Information Center

    Hayford, Sarah R.; Furstenberg, Frank F., Jr.

    2008-01-01

    As the transition to adulthood becomes more protracted and less orderly, fewer young people occupy adult roles and experience the social control associated with these roles. One might therefore expect behaviors associated with the teenage years to spill over into older age groups, reflecting postponed entrance into full social adulthood. We test…

  12. Age distribution of Serra Geral (Paraná) flood basalts, southern Brazil

    USGS Publications Warehouse

    Fodor, R.V.; McKee, E.H.; Roisenberg, A.

    1989-01-01

    We evaluated 193 K-Ar ages (10 newly determined) of basaltic and differentiated rocks of the Serra Geral (Paraná) flood-basalt province for indications of magmatism occurring systematically with progressive rifting and complete separation ( ≈130-105 Ma) of South America from Africa. The K-Ar ages represent basalt emplacement between 35° and 19°S covering about 1,200,000 km2. We note that volcanism appears ubiquitous across the province between about 140 and 115 Ma, and that there are no significant age differences within that relate directly to progressive south-to-north tectonism. On the other hand, the oldest samples, about 140–160 Ma, are among those nearest the Brazil coastline (rift margin), perhaps suggesting migration of activity away from the rift with time. Studies of other flood-basalt provinces now indicate short (<3 m.y.) eruption periods, thereby pointing to the need for re-examination of Serra Geral ages by 40Ar-39Ar incremental heating techniques.

  13. Effects of aging on the fraction distribution and bioavailability of selenium in three different soils.

    PubMed

    Li, Jun; Peng, Qin; Liang, Dongli; Liang, Sijie; Chen, Juan; Sun, Huan; Li, Shuqi; Lei, Penghui

    2016-02-01

    Aging refers to the processes by which the mobility and bioavailability of metals in soil decline with time. Although long-term aging is a key process that needs to be considered in risk assessment of metals, few investigations has been attempted to determine whether and how residence time influences the selenium (Se) fractions and bioavailability in soil. In this study, the fractions of Se in soils was evaluated, and bioavailability were assessed by measuring Se concentration in pak choi (Brassica chinensis L.). Results showed that the change of soil available Se in all tested soils divided into two phases: rapid decrease at the initial time (42 d) and slow decline thereafter. The second-order equation could describe the decrease processes of available Se in tested soils during the entire incubation time (R(2) > 0.99), while parabolic diffusion equation had less goodness of fit. Those results indicated that Se aging was controlled not only by diffusion process but also by other processes such as nucleation/precipitation, adsorption/desorption with soil component, occlusion by organic matter and reduction reaction. Soil available Se fractions tended to transform to more stable fractions during aging. The changes of Se concentration in pak choi were consistent with the variation in soil available Se content. In addition, 21 d could be reference for the time of Se aging reaching stabilization in krasnozems and fluvo-aquic soil, and 30 d for black soil. Results could provide theoretical basis to formulate environmental quality criterion and choose the equilibrium time before implementing a pot experiment in Se-spiked soils. PMID:26606190

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

    PubMed Central

    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

  15. Prevalence of factor V Leiden and prothrombin G20210A mutation in a large French population selected for nonthrombotic history: geographical and age distribution.

    PubMed

    Mazoyer, Elisabeth; Ripoll, Laurent; Gueguen, René; Tiret, Laurence; Collet, Jean-Philippe; dit Sollier, Claire Bal; Roussi, Jacqueline; Drouet, Ludovic

    2009-10-01

    Among inherited risk factors for venous thrombosis, the most common are the FV-G1691A and FII-G20210A polymorphisms. The FV-G1691A polymorphism is preferentially observed in Europe, with differences between European countries. The FII-G20210A polymorphism is observed all over the world. The study was designed to compare the prevalence of the FV-G1691A and FII-G20210A polymorphisms in a large French population of unrelated individuals with no thrombotic disease history and to determine the age and geographical distributions. Over a period of 18 months, 6154 individuals were included throughout France and FV-G1691A and FII-G20210A polymorphisms were determined. The FV-G1691A prevalence was 3.84% (95% confidence interval 3.35-4.33) and the FII-G20210A prevalence was 3.07% (95% CI 2.63-3.51). A north-east/south-west gradient was observed in the FV-G1691A geographical distribution. No difference was observed in the geographical distribution of FII-G20210A polymorphism nor in the age distribution of the two polymorphisms. The prevalence of the two polymorphisms was similar whatever the blood group (O or non-O). Plasma D-dimers were significantly higher in healthy individuals with FV-G1691A but not in individuals with FII-G20210A. Thirty percent of variation in plasma prothrombin level was explained by environmental factors (serum cholesterol, age, oral contraception, hormonal replacement therapy, body mass index, sex) and genetic factors (FII-G20210A). As expected, individuals with FII-G20210A displayed higher plasma prothrombin level compared with individuals with wild type. However, this was not associated with a modification of the fibrin clot elastic modulus. This study shows a differential distribution of the two polymorphisms among the French territory. These polymorphisms confer a very mild hypercoagulable state as shown by the limited increased in basal D-dimers in mutated FV-G1691A populations and only a trend that does not reach statistical significance for FII

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Lunar crater arcs. [origins, distribution and age classification of Pre-Imbrian families

    NASA Technical Reports Server (NTRS)

    Jaffe, L. D.; Bulkley, E. O.

    1976-01-01

    An analysis has been made of the tendency of large lunar craters to lie along circles. A catalog of the craters at least 50 km in diameter was prepared first, noting position, diameter, rim sharpness and completion, nature of underlying surface, and geological age. The subset of those craters 50-400 km in diameter was then used as input to computer programs which identified each 'family' of four or more craters of selected geological age lying on a circular arc. For comparison, families were also identified for randomized crater models in which the crater spatial density was matched to that on the moon, either overall or separately for mare and highland areas. The observed frequency of lunar arcuate families was statistically highly significantly greater than for the randomized models, for craters classified as either late-pre-Imbrian (Nectarian), middle pre-Imbrian, or early pre-Imbrian, as well as for a number of larger age-classes. The lunar families tend to center in specific areas of the moon; these lie in highlands rather than maria and are different for families of Nectarian craters than for pre-Nectarian. The origin of the arcuate crater groupings is not understood.

  18. Study of 500 patients with limb joint osteoarthritis. I. Analysis by age, sex, and distribution of symptomatic joint sites.

    PubMed Central

    Cushnaghan, J; Dieppe, P

    1991-01-01

    Five hundred subjects with symptomatic limb joint osteoarthritis, who had been referred to a rheumatologist, were enrolled into a continuing study. They comprised 342 women (mean age 65.3) and 158 men (mean age 59.7), with a mean symptom duration of 15.4 years at entry. Only 31 patients (6%) had symptomatic osteoarthritis of one joint alone; however, in a further 205 (41%) the disease was limited to one site. One hundred and eighty two (36.4%) had two sites affected and 82 (16.4%) three or more sites of symptomatic osteoarthritis. Of 847 affected joints the most commonly involved were 349 (41.2%) knees, 254 (30%) hands, and 161 (19%) hips. Hip disease stood out as a separate entity, often occurring alone, and having a stronger male preponderance and different associations than osteoarthritis at other joint sites. Knee and hand disease were significantly associated in women. Obesity, hypertension, and Heberden's nodes were common. The number of sites affected, as well as the distribution, was strongly related to age as well as sex, suggesting that polyarticular osteoarthritis arises from slow acquisition of new joint sites in a non-random distribution. 'Generalised' osteoarthritis did not emerge as a distinct entity. PMID:1994877

  19. Spatial distributions of phosphorylated membrane proteins aquaporin 0 and MP20 across young and aged human lenses.

    PubMed

    Gutierrez, Danielle B; Garland, Donita L; Schwacke, John H; Hachey, David L; Schey, Kevin L

    2016-08-01

    In the human ocular lens it is now realized that post-translational modifications can alter protein function and/or localization in fiber cells that no longer synthesize proteins. The specific sites of post-translational modification to the abundant ocular lens membrane proteins AQP0 and MP20 have been previously identified and their functional effects are emerging. To further understand how changes in protein function and/or localization induced by these modifications alter lens homeostasis, it is necessary to determine the spatial distributions of these modifications across the lens. In this study, a quantitative LC-MS approach was used to determine the spatial distributions of phosphorylated AQP0 and MP20 peptides from manually dissected, concentric layers of fiber cells from young and aged human lenses. The absolute amounts of phosphorylation were determined for AQP0 Ser235 and Ser229 and for MP20 Ser170 in fiber cells from the lens periphery to the lens center. Phosphorylation of AQP0 Ser229 represented a minor portion of the total phosphorylated AQP0. Changes in spatial distributions of phosphorylated APQ0 Ser235 and MP20 Ser170 correlated with regions of physiological interest in aged lenses, specifically, where barriers to water transport and extracellular diffusion form. PMID:27339748

  20. Simulating the grain-size distribution of Wisconsinan age glaciofluvial sediments: Applications to fluid transport

    SciTech Connect

    Webb, E.K.; Anderson, M.P. )

    1991-03-01

    A sedimentary deposition model, SEDSIM, was used to simulate the deposition of glaciofluvial sediments in south-central Wisconsin. These types of deposits are present at or near the surface over much of the northern United States and have a high contamination potential. They also represent relatively recent analogs for ancient braided stream systems. Sixty sediment samples were used to determine the average sediment properties for a facies assemblage located 8-10 km from the ice margin. A regional depositional system was simulated, using SEDSIM, to determine the range of input values that reproduced the observed average sediment characteristics. Progressively smaller scale models were constructed to produce more detailed estimates of the grain-size distribution. the grain-size estimates from the finest scale model were translated into relative hydraulic conductivity values using the method of Hazen. The resulting conductivities were incorporated into a fluid flow model to illustrate the control that heterogeneity of petrologic properties has on the direction and rate of fluid movement. This work indicates that a wide range of input parameters will reproduce the bulk sediment properties. Furthermore, small-scale features may not be reproduced under the assumptions incorporated in the current SEDSIM code. Thus, for sedimentary depositional models to be used to predict permeability and porosity distributions, or to interpret paleo-flow conditions, one must determine calibration targets that are more sensitive to flow parameters than bulk grain-size distributions.

  1. Fundamental Parameters and Spectral Energy Distributions of Young and Field Age Objects with Masses Spanning the Stellar to Planetary Regime

    NASA Astrophysics Data System (ADS)

    Filippazzo, Joe; Rice, Emily L.; Faherty, Jacqueline K.; Cruz, Kelle L.; Godfrey, Paige A.; BDNYC

    2016-01-01

    The physical and atmospheric properties of ultracool dwarfs are deeply entangled due to the degenerate effects of mass, age, metallicity, clouds and dust, activity, rotation, and possibly even formation mechanism on observed spectra. Accurate determination of fundamental parameters for a wide diversity of objects at the low end of the IMF is thus crucial to testing stellar and planetary formation theories. To determine these quantities, we constructed and flux calibrated nearly-complete spectral energy distributions (SEDs) for 221 M, L, T, and Y dwarfs using published parallaxes and 0.3-40 μm spectra and photometry. From these homogeneous SEDs, we calculated bolometric luminosity (Lbol), effective temperature (Teff), mass, surface gravity, radius, spectral indexes, synthetic photometry, and bolometric corrections (BCs) for each object. We used these results to derive Lbol, Teff, and BC polynomial relations across the entire very-low-mass star/brown dwarf/planetary mass regime. We use a subsample of objects with age constraints based on nearby young moving group membership, companionship with a young star, or spectral signatures of low surface gravity to define new age-sensitive diagnostics and characterize the reddening of young substellar atmospheres as a redistribution of flux from the near-infrared into the mid-infrared. Consequently we find the SED flux pivots at Ks band, making BCKs as a function of spectral type a tight and age independent relationship. We find that young L dwarfs are systematically 300 K cooler than field age objects of the same spectral type and up to 600 K cooler than field age objects of the same absolute H magnitude. Finally, we present preliminary comparisons of these empirical results to best fit parameters from four different model atmosphere grids via Markov-Chain Monte Carlo analysis in order to create prescriptions for the reliable and efficient characterization of new ultracool dwarfs.

  2. Provenance from zircon U-Pb age distributions in crustally contaminated granitoids

    NASA Astrophysics Data System (ADS)

    Bahlburg, Heinrich; Berndt, Jasper

    2016-05-01

    The basement of sedimentary basins is often entirely covered by a potentially multi-stage basin fill and therefore removed from direct observation and sampling. Melts intruding through the basin stratigraphy at a subsequent stage in the geological evolution of a region may assimilate significant volumes of country rocks. This component may be preserved in the intrusive body either as xenoliths or it may be reflected only by the age spectrum of incorporated zircons. Here we present the case of an Ordovician calc-alkaline intrusive belt in NW Argentina named the "Faja Eruptiva de la Puna Oriental" (Faja Eruptiva), which in the course of intrusion sampled the unexposed and unknown basement of the Ordovician basin in this region, and parts of the basin stratigraphy. We present new LA-ICP-MS U-Pb ages on zircons from 9 granodiorites and granites of the Faja Eruptiva. The main part of the Faja Eruptiva intruded c. 445 Ma in the Late Ordovician. The zircon ages obtained from the intrusive rocks have a large spread between 2683.5 ± 21.6 and 440.0 ± 4.9 Ma and reflect the underlying crust and may be interpreted in several ways. The inherited zircons may have been derived from the oldest known unit in the region, the thick siliciclastic turbidite successions of the upper Neoproterozoic-lower Cambrian Puncoviscana Formation, which is inferred to represent the basement of the NW Argentina. The basement to the Puncoviscana Formation is not known. Alternatively, the inherited zircons may reflect the geochronological structure of the entire unexposed Early Paleozoic crust underlying this region of which the Puncoviscana Formation was only one component. This crust likely contained rocks pertaining to and detritus derived from earlier orogenic cycles of the southwestern Amazonia craton, including sources of Early Meso- and Paleoproterozoic age. Detritus derived, in turn, from the Faja Eruptiva intrusive belt reflects the origin of the granitoids as well as the inherited

  3. Impact of Hydrologic and Micro-topographic Variabilities on Spatial Distribution of Mean Soil-Nitrogen Age

    NASA Astrophysics Data System (ADS)

    Woo, D.; Kumar, P.

    2015-12-01

    Excess reactive nitrogen in soils of intensively managed agricultural fields 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 3-dimensional model to characterize the spatially distributed ``age" of soil-nitrogen (nitrate and ammonia-ammonium) across a watershed. We use the general theory of age, which provides an assessment of the elapsed time since nitrogen is introduced into the soil system. Micro-topographic variability incorporates heterogeneity of nutrient transformations and transport associated with topographic depressions that form temporary ponds and produce prolonged periods of anoxic conditions, and roadside agricultural ditches that support rapid surface movement. This modeling effort utilizes 1-m Light Detection and Ranging (LiDAR) data. We find a significant correlation between hydrologic variability and mean nitrate age that enables assessment of preferential flow paths of nitrate leaching. The estimation of the mean nitrogen age can thus serve as a tool to disentangle complex nitrogen dynamics by providing the analysis of the time scales of soil-nitrogen transformation and transport processes without introducing additional parameters.

  4. Distributed neural representations of logical arguments in school-age children.

    PubMed

    Mathieu, Romain; Booth, James R; Prado, Jérôme

    2015-03-01

    Children's understanding of linear-order (e.g., Dan is taller than Lisa, Lisa is taller than Jess) and set-inclusion (i.e., All tulips are flowers, All flowers are plants) relationships is critical for the acquisition of deductive reasoning, that is, the ability to reach logically valid conclusions from given premises. Behavioral and neuroimaging studies in adults suggest processing differences between these relations: While arguments that involve linear-orders may be preferentially associated with spatial processing, arguments that involve set-inclusions may be preferentially associated with verbal processing. In this study, we used functional magnetic resonance imaging to investigate whether these processing differences appear during the period of elementary school in development. Consistent with previous studies in adults, we found that arguments that involve linear-order and set-inclusion relationships preferentially involve spatial and verbal brain mechanisms (respectively) in school-age children (9-14 year olds). Because this neural sensitivity was not related to age, it likely emerges before the period of elementary education. However, the period of elementary education might play an important role in shaping the neural processing of logical reasoning, as indicated by developmental changes in frontal and parietal regions that were dependent on the type of relation.

  5. Distributed neural representations of logical arguments in school-age children

    PubMed Central

    Mathieu, Romain; Booth, James R.; Prado, Jérôme

    2016-01-01

    Children’s understanding of linear-order (e.g., Dan is taller than Lisa, Lisa is taller than Jess) and set-inclusion (i.e., All tulips are flowers, All flowers are plants) relationships is critical for the acquisition of deductive reasoning, i.e., the ability to reach logically valid conclusions from given premises. Behavioral and neuroimaging studies in adults suggest processing differences between these relations: While arguments that involve linear-orders may be preferentially associated with spatial processing, arguments that involve set-inclusions may be preferentially associated with verbal processing. In the present study, we used functional magnetic resonance imaging (fMRI) to investigate whether these processing differences appear during the period of elementary school in development. Consistent with previous studies in adults, we found that arguments that involve linear-order and set-inclusion relationships preferentially involve spatial and verbal brain mechanisms (respectively) in school-age children (9 to 14 year olds). Because this neural sensitivity was not related to age, it likely emerges before the period of elementary education. However, the period of elementary education might play an important role in shaping the neural processing of logical reasoning, as indicated by developmental changes in frontal and parietal regions that were dependent upon the type of relation. PMID:25355487

  6. Comparisons of the galaxy age, stellar velocity dispersion and K-band luminosity distributions between grouped galaxies and isolated ones

    NASA Astrophysics Data System (ADS)

    Wu, Ping; Deng, Xin-Fa

    2016-02-01

    In two volume-limited Main galaxy samples of the Sloan Digital Sky Survey Data Release 10 (SDSS DR10), we compare the age, stellar velocity dispersion and K-band luminosity distributions of grouped galaxies with those of isolated galaxies, to explore the environmental dependence of these properties of galaxies. It is found that grouped galaxies have preferentially larger stellar velocity dispersions and are preferentially older than isolated galaxies. We also note apparent difference of K-band luminosity distribution at both extremes of density in the luminous volume-limited Main galaxy sample: grouped galaxies are preferentially more luminous than isolated galaxies, while this difference in the faint volume-limited Main galaxy sample is very small.

  7. Spatial and Seasonal Distribution of American Whaling and Whales in the Age of Sail

    PubMed Central

    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 18th to early 20th 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. PMID:22558102

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

    PubMed

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

    PubMed Central

    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

  10. Barrier height distribution and dipolar relaxation in metal-insulator-semiconductor junctions with molecular insulator: Ageing effects

    NASA Astrophysics Data System (ADS)

    Fadjie-Djomkam, A. B.; Ababou-Girard, S.; Godet, C.

    2012-12-01

    Electrical transport through molecular monolayers being very sensitive to disorder effects, admittance and current density characteristics of Hg//C12H25 - n Si junctions incorporating covalently bonded n-alkyl molecular layers, were investigated at low temperature (150-300 K), in the as-grafted state and after ageing at the ambient. This comparison reveals local oxidation effects both at the submicron scale in the effective barrier height distribution and at the molecular scale in the dipolar relaxation. In the bias range dominated by thermionic emission and modified by the tunnel barrier (TB) attenuation, exp(-β0dT), where dT is the thickness of the molecular tunnel barrier and β0 is the inverse attenuation length at zero applied bias, some excess current is attributed to a distribution of low barrier height patches. Complementary methods are used to analyze the current density J(V, T) characteristics of metal-insulator-semiconductor tunnel diodes. Assuming a Gaussian distribution of barrier heights centered at qΦB provides an analytical expression of the effective barrier height, qΦEFF(T)=qΦB+(kT)β0dT-(qδΦ)2/2kT; this allows fitting of the distribution standard deviation δΦ and tunnel parameter (β0dT) over a wide temperature range. In a more realistic modeling including the voltage dependence of barrier height and circular patch area, the so-called "pinch-off" effect is described by a distribution of parameter γ =3(ΔPRP2/4)1/3, which combines interface potential modulation and patch area variations. An arbitrary distribution of γ values, fitted to low-temperature J(V) data, is equally well described by Gaussian or exponential functions. Ageing in air also increases the interface oxidation of Si substrate and affects the density of localized states near mid gap, which typically rises to the high 1011 eV-1 cm-2 range, as compared with DS < 1011 eV-1 cm-2 in the as-grafted state. The bias-independent relaxation observed near 1 kHz at low temperature

  11. Percentile Distributions of Birth Weight according to Gestational Ages in Korea (2010-2012)

    PubMed Central

    2016-01-01

    The Pediatric Growth Chart (2007) is used as a standard reference to evaluate weight and height percentiles of Korean children and adolescents. Although several previous studies provided a useful reference range of newborn birth weight (BW) by gestational age (GA), the BW reference analyzed by sex and plurality is not currently available. Therefore, we aimed to establish a national reference range of neonatal BW percentiles considering GA, sex, and plurality of newborns in Korea. The raw data of all newborns (470,171 in 2010, 471,265 in 2011, and 484,550 in 2012) were analyzed. Using the Korean Statistical Information Service data (2010–2012), smoothed percentile curves (3rd–97th) by GA were created using the lambda-mu-sigma method after exclusion and the data were distinguished by all live births, singleton births, and multiple births. In the entire cohort, male newborns were heavier than female newborns and singletons were heavier than twins. As GA increased, the difference in BW between singleton and multiples increased. Compared to the previous data published 10 years ago in Korea, the BW of newborns 22–23 gestational weeks old was increased, whereas that of others was smaller. Other countries' data were also compared and showed differences in BW of both singleton and multiple newborns. We expect this updated data to be utilized as a reference to improve clinical assessments of newborn growth. PMID:27247504

  12. Distribution, facies, ages, and proposed tectonic associations of regionally metamorphosed rocks in northern Alaska

    SciTech Connect

    Dusel-Bacon, C.; Brosge, W.P.; Till, A.B.; Doyle, E.O.; Mayfield, C.F.; Reiser, H.N.; Miller, T.P.

    1989-01-01

    Approximately half of the exposed bedrock in northern Alaska has been regionally metamorphosed. In the southern Brooks Range and on the Seward Peninsula, continental rocks experienced a clockwise pressure-temperature path that evolved during Middle Jurassic to late Early Cretaceous time from the low- to high-temperature subfacies of the blueschist facies and, finally, due to decreasing pressure, evolved to the greenschist facies. Metamorphism in the southern Brooks Range was associated with north-vergent compression along a south-dipping subduction zone that emplaced the oceanic rocks of the Angayucham terrane onto the continental margin. High-pressure metamorphism on the Seward Peninsula probably had a similar origin to that in the southern Brooks Range, but remnants of the overriding plate have not been identified, and the mechanism by which the high-pressure rocks in the two areas were separated is not known. In the Ruby geanticline, glaucophane, attesting to high-pressure metamorphism, is sporadically developed both within the continental rocks of the lower plate and, less commonly, near the base of the overlying oceanic thrust sheets. Although the majority of the metamorphic episodes that affected northern Alaska occurred during the Mesozoic, older episodes have been documented or are suspected in a few areas.

  13. The Spatio-temporal Distribution of Japanese Encephalitis Cases in Different Age Groups in Mainland China, 2004 – 2014

    PubMed Central

    Wang, Huanyu; Song, Miao; Li, Minghua; Fu, Shihong; Lv, Zhi; He, Ying; Lei, Wenwen; Wang, Bin; Lu, Xiaoqing; Liang, Guodong

    2016-01-01

    Background Japanese encephalitis (JE) is very prevalent in China, but the incidence of JE among children has been greatly reduced by extensive promotion of vaccinations. The incidence of JE among adults, however, has increased in some parts of China. Methods/Principal Findings Data on JE in mainland China, in terms of incidence, gender, and age, were collected between 2004 and 2014. We conducted spatial and temporal analyses on data from different age groups. Generally, children aged 0–15 years still represent the major population of JE cases in China, despite the gradual decrease in incidence over years. However, the incidence of JE among adults in several provinces is notably higher than the national average, especially during the epidemic waves in 2006, 2009, and 2013. The JE cases in the 0–15-year-old group are distributed mainly in the area south of the Yangtze River, with peak incidence occurring from July to September. In the adult group, especially for those over 40 years old, the JE cases are concentrated mainly in the area north of the Yangtze River. JE incidence in the adult group in September and October is significantly greater compared to the other groups. Further analysis using Local Indicators of Spatial Association (LISA) reveals that the distribution of adult JE cases in the six provinces north of the Yangtze River, between north 30–35° latitude and east 110–130° longitude, is a hotspot for adult JE cases. Conclusions/Significance The rate of JE case increase for adults is much greater than for children and has become a public health issue. Therefore, studies on the necessity and feasibility of vaccinating adults who live in JE-endemic areas, but have never been vaccinated for JE, should become a new focus of JE prevention in the future. PMID:27050414

  14. Data on the distribution of cancer incidence and death across age and sex groups visualized using multilevel spie charts.

    PubMed

    Feitelson, Dror G

    2016-04-01

    Cancer incidence and death statistics are typically recorded for multiple age and sex brackets, leading to large data tables which are difficult to digest. Effective visualizations of this data would allow practitioners, policy makers, and the general public to comprehend the data more readily and act on it appropriately. We introduce multilevel spie charts to create a combined visualization of cancer incidence and death statistics. Spie charts combine multiple pie charts, where the base pie chart (representing the general population) is used to set the angles of slices, and the superimposed ones use variable radii to portray the cancer data. Spie charts of cancer incidence and death statistics from Israel for 2009-2011 are used as an illustration. These charts clearly show various patterns of how cancer incidence and death distribute across age and sex groups, illustrating (1) absolute numbers and (2) rates per 100,000 population for different age and sex brackets. In addition, drawing separate charts for different cancer types illustrates relative mortality, both (3) across cancer types and (4) mortality relative to incidence. Naturally, this graphical depiction can be used for other diseases as well.

  15. AGE AND MASS CONSTRAINTS FOR A YOUNG MASSIVE CLUSTER IN M31 BASED ON SPECTRAL ENERGY DISTRIBUTION FITTING

    SciTech Connect

    Ma Jun; Wang Song; Wu Zhenyu; Fan Zhou; Yang Yanbin; Zhang Tianmeng; Wu Jianghua; Zhou Xu; Jiang Zhaoji; Chen Jiansheng

    2011-03-15

    VDB0-B195D is a massive, blue star cluster in M31. It was observed as part of the Beijing-Arizona-Taiwan-Connecticut (BATC) Multicolor Sky Survey using 15 intermediate-band filters covering a wavelength range of 3000-10000 A. Based on aperture photometry, we obtain its spectral energy distribution (SED) as defined by the 15 BATC filters. We apply previously established relations between the BATC intermediate-band and the Johnson-Cousins UBVRI broadband systems to convert our BATC photometry to the standard system. A detailed comparison shows that our newly derived VRI magnitudes are fully consistent with previous results, while our new B magnitude agrees to within 2{sigma}. In addition, we determine the cluster's age and mass by comparing its SED (from 3000 to 20000 A, comprising photometric data in the 15 BATC intermediate bands, optical broadband BVRI, and Two Micron All Sky Survey near-infrared JHK{sub s} data) with theoretical stellar population synthesis models, resulting in age and mass determinations of 60.0 {+-} 8.0 Myr and (1.1-1.6) x 10{sup 5} M{sub sun}, respectively. This age and mass confirms previous suggestions that VDB0-B195D is a young massive cluster in M31.

  16. Identification of defect distribution at ferroelectric domain walls from evolution of nonlinear dielectric response during the aging process

    NASA Astrophysics Data System (ADS)

    Mokrý, Pavel; Sluka, Tomáš

    2016-02-01

    The motion of ferroelectric domain walls greatly contributes to the macroscopic dielectric and piezoelectric response of ferroelectric materials. The domain-wall motion through the ferroelectric material is, however, hindered by pinning on crystal defects, which substantially reduces these contributions. Here, using thermodynamic models based on the Landau-Ginzburg-Devonshire theory, we find a relation between the microscopic reversible motion of nonferroelastic 180∘ domain walls interacting with a periodic array of pinning centers and the nonlinear macroscopic permittivity. We show that the reversible motion of domain walls can be split into two basic modes: first, the bending of a domain wall between pinning centers, and, second, the uniform movement of the domain-wall plane. We show that their respective contributions may change when the distribution of pinning centers is rearranged during the material aging. We demonstrate that it is possible to indicate which mechanism of the domain-wall motion is affected during material aging. This allows one to judge whether the defects only homogeneously accumulate at domain walls or prefer to align in certain directions inside the domain-wall plane. We suggest that this information can be obtained using simple macroscopic dielectric measurements and a proper analysis of the nonlinear response. Our results may therefore serve as a simple and useful tool to obtain details on domain-wall pinning in an aging process.

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

    PubMed Central

    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

  18. Sorption and distribution of aged atrazine residues in the drainage system of an outdoor lysimeter experiment

    NASA Astrophysics Data System (ADS)

    Jablonowski, N. D.; Schäffer, A.; Burauel, P.

    2009-04-01

    Even though the environmental impact of the herbicide atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] is a matter of controversy, it is still extensively applied for agricultural purposes. Particularly in the US, atrazine has been applied to approximately 70% of all corn acreages in the last 18 years. Atrazine is banned in the EU but its use is increasing in countries like China, Brazil and India. Therefore, the worldwide soil burden of this compound must be enormous. Atrazine has been found to be highly persistent in the environment and it has been suggested that it is moderately mobile in the soil profile. As a result, it is found in most groundwater aquifers and surface waters in agricultural areas in the US. Even in Germany, where it was prohibited in 1991, it is still found in groundwater wells below agriculturally used land where it was formerly applied. For a long-term outdoor lysimeter experiment with a disturbed soil column, a drainage system of fine gravel was originally embedded at the bottom of the lysimeter. In this drainage system, atrazine and its metabolite 2-hydroxy-atrazine were extracted as long as 22 years after the last atrazine application. Due to the radiolabelling, the spatial distribution of the atrazine residues can be evaluated in fractions like fine clay particles attached to the gravel or in the gravel itself. Approximately 2% of the total gravel consisted of carbonaceous, slag-like particles which might retain most of the atrazine and its residues. The latest data will be presented at the session.

  19. The morphologic and neurochemical basis of dementia: aging, hierarchical patterns of lesion distribution and vulnerable neuronal phenotype.

    PubMed

    Hof, P R; Giannakopoulos, P; Vickers, J C; Bouras, C; Morrison, J H

    1995-01-01

    Alzheimer's disease is the most common form of dementia in elderly individuals. Approximately 11% of the population older than 65, and up to 50% of individuals over 85 qualify as having "probable Alzheimer's disease" on the basis of clinical evaluation. Since the early description of the clinical symptoms and neuropathologic features of Alzheimer's disease, there has been an extraordinary growth in the knowledge of the morphologic and molecular characteristics of Alzheimer's disease. Although the pathogenetic events that lead to dementia are not yet fully understood, several hypotheses regarding the formation of the hallmark pathologic structures of Alzheimer's disease have been proposed. In this context, the use of specific histochemical techniques in the primate brain has greatly expanded our understanding of neuron typology, connectivity and circuit distribution in relation to neurochemical identity. In this respect, very specific subsets of cortical neurons and cortical afferents can be identified by their particular content of certain neurotransmitters and structural proteins. In this article, we discuss the possible relationships between the distribution of pathologic changes in aging, Alzheimer's disease, and possibly related dementing conditions, in the context of the specific elements of the cortical circuitry that are affected by these alterations. Also, evidence for links between the neurochemical phenotype of a given neuron and its relative vulnerability or resistance to the degenerative process are presented in order to correlate the distribution of cellular pathologic changes, neurochemical characteristics related to vulnerability, and affected cortical circuits.

  20. MitoTimer probe reveals the impact of autophagy, fusion, and motility on subcellular distribution of young and old mitochondrial protein and on relative mitochondrial protein age.

    PubMed

    Ferree, Andrew W; Trudeau, Kyle; Zik, Eden; Benador, Ilan Y; Twig, Gilad; Gottlieb, Roberta A; Shirihai, Orian S

    2013-11-01

    To study mitochondrial protein age dynamics, we targeted a time-sensitive fluorescent protein, MitoTimer, to the mitochondrial matrix. Mitochondrial age was revealed by the integrated portions of young (green) and old (red) MitoTimer protein. Mitochondrial protein age was dependent on turnover rates as pulsed synthesis, decreased import, or autophagic inhibition all increased the proportion of aged MitoTimer protein. Mitochondrial fusion promotes the distribution of young mitochondrial protein across the mitochondrial network as cells lacking essential fusion genes Mfn1 and Mfn2 displayed increased heterogeneity in mitochondrial protein age. Experiments in hippocampal neurons illustrate that the distribution of older and younger mitochondrial protein within the cell is determined by subcellular spatial organization and compartmentalization of mitochondria into neurites and soma. This effect was altered by overexpression of mitochondrial transport protein, RHOT1/MIRO1. Collectively our data show that distribution of young and old protein in the mitochondrial network is dependent on turnover, fusion, and transport.

  1. Aspen Ecology in Rocky Mountain National Park: Age Distribution, Genetics, and the Effects of Elk Herbivory

    USGS Publications Warehouse

    Zeigenfuss, Linda C.; Binkley, Dan; Tuskan, Gerald A.; Romme, William H.; Yin, Tongming; DiFazio, Stephen; Singer, Francis J.

    2008-01-01

    Lack of recruitment and canopy replacement of aspen (Populus tremuloides) stands that grow on the edges of grasslands on the low-elevation elk (Cervus elaphus) winter range of Rocky Mountain National Park (RMNP) in Colorado have been a cause of concern for more than 70 years. We used a combination of traditional dendrochronology and genetic techniques as well as measuring the characteristics of regenerating and nonregenerating stands on the elk winter range to determine when and under what conditions and estimated elk densities these stands established and through what mechanisms they may regenerate. The period from 1975 to 1995 at low elevation on the east side had 80-95 percent fewer aspen stems than would be expected based on the trend from 1855 through 1965. The age structure of aspen in the park indicates that the interacting effects of fires, elk population changes, and livestock grazing had more-or-less consistent effects on aspen from 1855 to 1965. The lack of a significant change in aspen numbers in recent decades in the higher elevation and west side parts of the park supports the idea that the extensive effects of elk browsing have been more important in reducing aspen numbers than other factors. The genetic variation of aspen populations in RMNP is high at the molecular level. We expected to find that most patches of aspen in the park were composed of a single clone of genetically identical trees, but in fact just 7 percent of measured aspen patches consisted of a single clone. A large frequency of polyploid (triploid and tetraploid) genotypes were found on the low elevation, east-side elk winter range. Nonregenerating aspen stands on the winter range had greater annual offtake, shorter saplings, and lower density of mid-height (1.5-2.5 m) saplings than regenerating stands. Overwinter elk browsing, however, did not appear to inhibit the leader length of aspen saplings. The winter range aspen stands of RMNP appear to be highly resilient in the face of

  2. Distribution patterns, properties and ages of Pleistocene periglacial slope deposits in the eastern Rhenish Massif

    NASA Astrophysics Data System (ADS)

    Sauer, Daniela; Scholten, Thomas; Felix-Henningsen, Peter; Kadereit, Annette

    2010-05-01

    between an Upper Layer and the rock in all expositions. The total thickness of the PPSD sequence on quartzite grows downslope, mainly due to an increasing thickness of the Basal Layer. In addition, Intermediate Layers contribute to the thickness of the PPSD profile on the lower slopes in SE- and NE-exposition. This can be partly explained by enhanced loess sedimentation on the leeward slopes in an area of predominantly westerly winds. Additionally, sediments were best preserved on E slopes, because thaw-processes leading to remobilization and removal of formerly deposited sediments were less intensive there. In most of the upper slope profiles on diabase, an Upper Layer covers directly the rock. A Basal Layer starts between the upper and middle slope sites. In SE exposition, an Intermediate Layer appears already on the mid slope. The total thickness of the PPSD sequence reaches its maximum on the footslope, where several Basal Layers may occur on top of one another. With regard to the formation time of the different layers, it is assumed that Basal and Intermediate Layers could have formed during several cold periods of the Pleistocene. It is however most likely that pre-Wurmian layers were preserved only on footslopes, where several Basal Layers occur on top of each other. All other layers are probably of Wurmian age, because the steep slopes did not allow preservation of older sediments (in contrast to areas of Tertiary peneplains in the central Rhenish Massif). Infrared stimulated luminescence datings confirm the assumption that the Upper Layer was subject to gelisolifluction for the last time during the Younger Dryas, and that the remarkably constant thickness of about 50 cm of the Upper Layer represents the thickness of the active layer at that time.

  3. Age and spatial distribution of Holocene permafrost in Norway - model results and implications for glacier-permafrost interaction

    NASA Astrophysics Data System (ADS)

    Lilleoren, K. S.; Etzelmuller, B.; Gisnås, K.; Humlum, O.

    2011-12-01

    Following the last glaciation, cryogenic processes related to valley and cirque glaciers, permafrost and seasonal frost have dominated the Norwegian landscape development in high-mountain environments. This is evident by different landscape and landform features, like rock glaciers, block fields, palsas, ice-wedge polygons and ice-cored moraines. For Scandinavia the present regional distribution of mountain permafrost is reasonably well known, both through ground temperature measurements in boreholes, geophysical soundings and spatial modelling exercises. An important question in this context is the dynamics of permafrost during the Holocene, as a major factor for landscape development and geomorphological processes in high mountain areas of Scandinavia. In the present study mean annual air temperature deviation curves through Holocene have been compiled to drive a 1D heat flow model over the last 10 ka period for several mountain sites in Norway. At each site temperature-monitored boreholes were used to calibrate the model. Both an annual run and a seasonal run including monthly temperature variations were performed for each site. In addition the spatial distribution of permafrost during selected time periods of the Holocene were addressed using an equilibrium permafrost model on a 1*1 km resolution. The results of this study indicate an altitudinal zonation of relative permafrost age in Norway, where permafrost has existed continuously since the deglaciation in the highest areas, while large areas that is underlain by permafrost today were degraded during the Holocene Thermal Maximum (HTM). In all boreholes the deepest simulated permafrost occurred during the Little Ice Age (LIA), and also the largest areal distribution of Holocene permafrost in Norway is connected to the LIA. In addition, there exist a clear connection between the distribution of permafrost and presence of blockfields. These findings have several implications, such as for the subglacial

  4. Distribution of Candida albicans in the oral cavity of children aged 3-5 years of Uygur and Han nationality and their genotype in caries-active groups.

    PubMed

    Wu, N; Lin, J; Wu, L; Zhao, J

    2015-01-01

    We analyzed the distribution of Candida albicans in the oral cavity of 3-5-year-old children of Uygur and Han nationalities as well as their genotypes in caries-active groups in the Urumqi municipality. CHROMagar Candida was separately cultivated, and we identified 359 Uygur and Han children aged 3-5 years. We randomly selected 20 Han children and 20 Uygur children for this study. We chose a bacterial strain for polymerase chain reaction (PCR) 25S rDNA genotyping and random amplified polymorphic DNA (RAPD) genotyping. The rate of caries-active in Han children was higher than that in Uygur children, with values of 39.6 and 24.3%, respectively. The detection rate of C. albicans was closely correlated to the caries filling index classification (X(2) = 31.037, P = 0.000, r = 0.421; X(2) = 80.454, P = 0.000, r = 0.497). PCR of 25S rDNA from 40 strains of Han and Uygur children revealed 3 genotypes, while RAPD analysis revealed 5 genotypes. The distribution of 25S rDNA genotyping of Han children from PCR differed from that of Uygur children (X(2) = 7.697, P = 0.021), both of which were mainly the A type. RAPD genotyping of both Han and Uygur children showed similar results (X(2) = 1.573, P = 0.814). There were differences in the distributions of C. albicans in children of different nationalities. C. albicans is a key factor causing caries. The PCR 25S rDNA genotyping method is simple and sensitive, while the RAPD genotyping method is reliable and comprehensive. PMID:25730012

  5. The Modeling of Time-Varying Stream Water Age Distributions: Preliminary Investigations with Non-Conservative Solutes

    NASA Astrophysics Data System (ADS)

    Wilusz, D. C.; Harman, C. J.; Ball, W. P.

    2014-12-01

    Modeling the dynamics of chemical transport from the landscape to streams is necessary for water quality management. Previous work has shown that estimates of the distribution of water age in streams, the transit time distribution (TTD), can improve prediction of the concentration of conservative tracers (i.e., ones that "follow the water") based on upstream watershed inputs. A major challenge however has been accounting for climate and transport variability when estimating TDDs at the catchment scale. In this regard, Harman (2014, in review) proposed the Omega modeling framework capable of using watershed hydraulic fluxes to approximate the time-varying TTD. The approach was previously applied to the Plynlimon research watershed in Wales to simulate stream concentration dynamics of a conservative tracer (chloride) including 1/f attenuation of the power spectra density. In this study we explore the extent to which TTDs estimated by the Omega model vary with the concentration of non-conservative tracers (i.e., ones whose concentrations are also affected by transformations and interactions with other phases). First we test the hypothesis that the TTD calibrated in Plynlimon can explain a large part of the variation in non-conservative stream water constituents associated with storm flow (acidity, Al, DOC, Fe) and base flow (Ca, Si). While controlling for discharge, we show a correlation between the percentage of water of different ages and constituent concentration. Second, we test the hypothesis that TTDs help explain variation in stream nitrate concentration, which is of particular interest for pollution control but can be highly non-conservative. We compare simulation runs from Plynlimon and the agricultural Choptank watershed in Maryland, USA. Following a top-down approach, we estimate nitrate concentration as if it were a conservative tracer and examine the structure of residuals at different temporal resolutions. Finally, we consider model modifications to

  6. Age-related development and tissue distribution of T cell markers (CD4 and CD8a) in Chinese goose.

    PubMed

    Chen, Shun; Zhou, Qin; Cheng, Beibei; Yan, Bing; Yan, Xiaoling; Zhao, Qiurong; Wang, Mingshu; Jia, Renyong; Zhu, Dekang; Liu, Mafeng; Chen, Xiaoyue; Cheng, Anchun

    2015-06-01

    Aquatic birds play n critical role in the transmission and dissemination of many important pathogens such as avian influenza virus. The cell-mediated immunity is very important in eliminating the intracellular antigens. Expression of CD4 and CD8 on T cell surface is essential for cell-mediated immune defence and T-cell development. However, the ontogeny of T lymphocytes in waterfowl is scarce and fragmentary. To address these questions, here we report the development and tissues distribution of CD4 and CD8α in goose embryo, gosling and goose by immunocytochemistry assay using monoclonal antibodies. Moreover, the age-related mRNA level of goose CD4 and CD8α in different immune tissues were study by real time quantitative PCR. Our results suggested that the high expression of CD4 and CD8α were readily found in thymus, which peaked at the first week post-hatch. And the highest expression level of CD4 and CD8α were detected in bursa of Fabricius, caecal tonsils, spleen and intestine at the second week, after that the expression level were gradually decreased. Interestingly, the remarkably high expression of CD4 and CD8α in Harderian gland were detected at the first week, which is about hundreds times more than that in other tissues. Our findings demonstrated that the development and the distribution of CD4 and CD8α are partly changed in an age-related way. Moreover, the histological morphogenesis of immune tissues were also discussed. Our results may shed lights on the better understand of T-cell mediate immunity in goose.

  7. Age, geochemical composition, and distribution of Oligocene ignimbrites in the northern Sierra Nevada, California: Implications for landscape morphology, elevation, and drainage divide geography of the Nevadaplano

    USGS Publications Warehouse

    Cassel, E.J.; Calvert, A.T.; Graham, S.A.

    2009-01-01

    To gain a better understanding of the topographic and landscape evolution of the Cenozoic Sierra Nevada and Basin and Range, we combine geochemical and isotopic age correlations with palaeoaltimetry data from widely distributed ignimbrites in the northern Sierra Nevada, California. A sequence of Oligocene rhyolitic ignimbrites is preserved across the modern crest of the range and into the western foothills. Using trace and rare earth element geochemical analyses of volcanic glass, these deposits have been correlated to ignimbrites described and isotopically dated in the Walker Lane fault zone and in central Nevada (Henry et al., 2004, Geologic map of the Dogskin mountain quadrangle; Washoe County, Nevada; Faulds et al., 2005, Geology, v. 33, p. 505-508). Ignimbrite deposits were sampled within the northern Sierra Nevada and western Nevada, and four distinct geochemical compositions were identified. The majority of samples from within the northern Sierra Nevada have compositions similar to the tuffs of Axehandle Canyon or Rattlesnake Canyon, both likely sourced from the same caldera complex in either the Clan Alpine Mountains or the Stillwater Range, or to the tuff of Campbell Creek, sourced from the Desatoya Mountains caldera. New 40Ar/39Ar age determinations from these samples of 31.2, 30.9, and 28.7Ma, respectively, support these correlations. Based on an Oligocene palinspastic reconstruction of the region, our results show that ignimbrites travelled over 200km from their source calderas across what is now the crest of the Sierra Nevada, and that during that time, no drainage divide existed between the ignimbrite source calderas in central Nevada and sample locations 200km to the west. Palaeoaltimetry data from Sierra Nevada ignimbrites, based on the hydrogen isotopic composition of hydration water in glass, reflect the effect of a steep western slope on precipitation and indicate that the area had elevations similar to the present-day range. These combined

  8. Age, composition, and areal distribution of the Pliocene Lawlor Tuff, and three younger Pliocene tuffs, California and Nevada

    USGS Publications Warehouse

    Sarna-Wojcicki, A. M.; Deino, A.L.; Fleck, R.J.; McLaughlin, R.J.; Wagner, D.; Wan, E.; Wahl, D.; Hillhouse, J.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. ?? 2011 Geological Society of America.

  9. Regional Evaluation of Groundwater Age Distributions Using Lumped Parameter Models with Large, Sparse Datasets: Example from the Central Valley, California, USA

    NASA Astrophysics Data System (ADS)

    Jurgens, B. C.; Bohlke, J. K.; Voss, S.; Fram, M. S.; Esser, B.

    2015-12-01

    Tracer-based, lumped parameter models (LPMs) are an appealing way to estimate the distribution of age for groundwater because the cost of sampling wells is often less than building numerical groundwater flow models sufficiently complex to provide groundwater age distributions. In practice, however, tracer datasets are often incomplete because of anthropogenic or terrigenic contamination of tracers, or analytical limitations. While age interpretations using such datsets can have large uncertainties, it may still be possible to identify key parts of the age distribution if LPMs are carefully chosen to match hydrogeologic conceptualization and the degree of age mixing is reasonably estimated. We developed a systematic approach for evaluating groundwater age distributions using LPMs with a large but incomplete set of tracer data (3H, 3Hetrit, 14C, and CFCs) from 535 wells, mostly used for public supply, in the Central Valley, California, USA that were sampled by the USGS for the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment or the USGS National Water Quality Assessment Programs. In addition to mean ages, LPMs gave estimates of unsaturated zone travel times, recharge rates for pre- and post-development groundwater, the degree of age mixing in wells, proportion of young water (<60 yrs), and the depth of the boundary between post-development and predevelopment groundwater throughout the Central Valley. Age interpretations were evaluated by comparing past nitrate trends with LPM predicted trends, and whether the presence or absence of anthropogenic organic compounds was consistent with model results. This study illustrates a practical approach for assessing groundwater age information at a large scale to reveal important characteristics about the age structure of a major aquifer, and of the water supplies being derived from it.

  10. Quantifying the distribution of nanodiamonds in pre-Younger Dryas to recent age deposits along Bull Creek, Oklahoma Panhandle, USA

    NASA Astrophysics Data System (ADS)

    Bement, Leland C.; Madden, Andrew S.; Carter, Brian J.; Simms, Alexander R.; Swindle, Andrew L.; Alexander, Hanna M.; Fine, Scott; Benamara, Mourad

    2014-02-01

    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.

  11. Quantifying the distribution of nanodiamonds in pre-Younger Dryas to recent age deposits along Bull Creek, Oklahoma Panhandle, USA

    PubMed Central

    Bement, Leland C.; Madden, Andrew S.; Carter, Brian J.; Simms, Alexander R.; Swindle, Andrew L.; Alexander, Hanna M.; Fine, Scott; Benamara, Mourad

    2014-01-01

    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. PMID:24449875

  12. Relative controls of external and internal variability on time-variable transit time distributions, and the importance of StorAge Selection function approaches

    NASA Astrophysics Data System (ADS)

    Kim, M.; Pangle, L. A.; Cardoso, C.; Lora, M.; Meira, A.; Volkmann, T. H. M.; Wang, Y.; Harman, C. J.; Troch, P. A. A.

    2015-12-01

    Transit time distributions (TTDs) are an efficient way of characterizing complex transport dynamics of a hydrologic system. Time-invariant TTD has been studied extensively, but TTDs are time-varying under unsteady hydrologic systems due to both external variability (e.g., time-variability in fluxes), and internal variability (e.g., time-varying flow pathways). The use of "flow-weighted time" has been suggested to account for the effect of external variability on TTDs, but neglects the role of internal variability. Recently, to account both types of variability, StorAge Selection (SAS) function approaches were developed. One of these approaches enables the transport characteristics of a system - how the different aged water in the storage is sampled by the outflow - to be parameterized by time-variable probability distribution called the rank SAS (rSAS) function, and uses it directly to determine the time-variable TTDs resulting from a given timeseries of fluxes in and out of a system. Unlike TTDs, the form of the rSAS function varies only due to changes in flow pathways, but is not affected by the timing of fluxes alone. However, the relation between physical mechanisms and the time-varying rSAS functions are not well understood. In this study, relative effects of internal and external variability on the TTDs are examined using observations from a homogeneously packed 1 m3 sloping soil lysimeter. The observations suggest the importance of internal variability on TTDs, and reinforce the need to account for this variability using time-variable rSAS functions. Furthermore, the relative usefulness of two other formulations of SAS functions and the mortality rate (which plays a similar role to SAS functions in the McKendrick-von Foerster model of age-structured population dynamics) are also discussed. Finally, numerical modeling is used to explore the role of internal and external variability for hydrologic systems with diverse geomorphic and climate characteristics

  13. Age- and gender-related changes in the distribution of osteocalcin in the extracellular matrix of normal male and female bone. Possible involvement of osteocalcin in bone remodeling.

    PubMed Central

    Ingram, R T; Park, Y K; Clarke, B L; Fitzpatrick, L A

    1994-01-01

    With increasing age, bone undergoes changes in remodeling that ultimately compromise the structural integrity of the skeleton. The presence of osteocalcin in bone matrix may alter bone remodeling by promoting osteoclast activity. Whether age- and/or gender-related differences exist in the distribution of osteocalcin within individual bone remodeling units is not known. In this study, we determined the immunohistochemical distribution of osteocalcin in the extracellular matrix of iliac crest bone biopsies obtained from normal male and female volunteers, 20-80 yr old. Four different distribution patterns of osteocalcin within individual osteons were arbitrarily defined as types I, II, III, or IV. The frequency of appearance of each osteon type was determined as a percent of the total osteons per histologic section. The proportion of osteons that stained homogeneously throughout the concentric lamellae (type I) decreased in females and males with increasing age. The proportion of osteons that lack osteocalcin in the matrix immediately adjacent to Haversian canals (type III) increased in females and males with age. Osteons staining intensely in the matrix adjacent to Haversian canals (type II) increased in females and was unchanged in aging males. Osteons that contained osteocalcin-positive resting lines (type IV) increased in bone obtained from males with increasing age but were unchanged in females. Sections of bone immunostained for osteopontin (SPP-I), osteonectin, and decorin did not reveal multiple patterns or alterations in staining with gender or increasing age. We suggest that the morphology of individual bone remodeling units is heterogeneous and the particular morphologic pattern of osteocalcin distribution changes with age and gender. These results suggest that differences in the distribution of osteocalcin in bone matrix may be responsible, in part, for the altered remodeling of bone associated with gender and aging. Images PMID:8132785

  14. Age and gender distribution of Hepatitis C virus prevalence and genotypes of individuals of physical examination in WuHan, Central China.

    PubMed

    Niu, ZhiLi; Zhang, PingAn; Tong, YongQing

    2016-01-01

    Approximately 170 million people in the world are infected with Hepatitis C virus (HCV). There are no published population based studies about the prevalence of HCV genotypes and the associations of genotype and Infection frequency with gender and age in WuHan. We aimed to investigate the distribution of HCV prevalence and genotypes among different gender and age patients with chronic HCV infection in WuHan from 2011 to 2015. A total of 2685 anti-HCV positive serum samples from individuals of physical examinationwere recruited from the Renmin Hospital of WuHan University, Hubei Province in China from January 2011 to December 2015. From these 2685 anti-HCV positive serum samples, 496 samples were with a positive PCR for HCV RNA. The number of HCV infection showed an increase with year, but the annual infection rate has remained similar (χ(2) = 2.94, P = 0.568). 2685 cases were infected with HCV from 2011 to 2015 in WuHan city of China. Blood transfusion (18.14 %) was the main routs of transmission, followed by Surgery (8.94 %). The highest prevalence of HCV infection was at the age group 50-59 (25.85 % of 2685) and the lowest prevalence was 0-9 (0.93 % of 2685). HCV genotype 1 was the most prevalent (73.39 %), followed by genotypes 2 (17.14 %), 3 (5.25 %) and 6 (3.22 %). Genotype 4 and 5 was not detected in these patients. The most prevalent subtype was subtype 1b (71.98 %), followed by genotypes 2a (17.14 %). Five patients had mixed infection across the HCV subtypes. Among all genotypes, genotype 1 was highest in both male (73.27 %) and female (73.47 %) patients, followed by genotype 2. Genotype 1 (male: 29.84 % of 496, vs female: 43.55 % of 496, χ(2) = 20.07, P < 0.0001), genotype 2 (male: 6.25 % of 496, vs female: 10.89 % of 496, χ(2) = 6.81, P = 0.009), and 6 (male: 1.41 % of 496, vs female: 1.81 % of 496, χ(2) = 0.626, P = 0.401) were more common in female patients than males, while no significant gender differences were

  15. Age and gender distribution of Hepatitis C virus prevalence and genotypes of individuals of physical examination in WuHan, Central China.

    PubMed

    Niu, ZhiLi; Zhang, PingAn; Tong, YongQing

    2016-01-01

    Approximately 170 million people in the world are infected with Hepatitis C virus (HCV). There are no published population based studies about the prevalence of HCV genotypes and the associations of genotype and Infection frequency with gender and age in WuHan. We aimed to investigate the distribution of HCV prevalence and genotypes among different gender and age patients with chronic HCV infection in WuHan from 2011 to 2015. A total of 2685 anti-HCV positive serum samples from individuals of physical examinationwere recruited from the Renmin Hospital of WuHan University, Hubei Province in China from January 2011 to December 2015. From these 2685 anti-HCV positive serum samples, 496 samples were with a positive PCR for HCV RNA. The number of HCV infection showed an increase with year, but the annual infection rate has remained similar (χ(2) = 2.94, P = 0.568). 2685 cases were infected with HCV from 2011 to 2015 in WuHan city of China. Blood transfusion (18.14 %) was the main routs of transmission, followed by Surgery (8.94 %). The highest prevalence of HCV infection was at the age group 50-59 (25.85 % of 2685) and the lowest prevalence was 0-9 (0.93 % of 2685). HCV genotype 1 was the most prevalent (73.39 %), followed by genotypes 2 (17.14 %), 3 (5.25 %) and 6 (3.22 %). Genotype 4 and 5 was not detected in these patients. The most prevalent subtype was subtype 1b (71.98 %), followed by genotypes 2a (17.14 %). Five patients had mixed infection across the HCV subtypes. Among all genotypes, genotype 1 was highest in both male (73.27 %) and female (73.47 %) patients, followed by genotype 2. Genotype 1 (male: 29.84 % of 496, vs female: 43.55 % of 496, χ(2) = 20.07, P < 0.0001), genotype 2 (male: 6.25 % of 496, vs female: 10.89 % of 496, χ(2) = 6.81, P = 0.009), and 6 (male: 1.41 % of 496, vs female: 1.81 % of 496, χ(2) = 0.626, P = 0.401) were more common in female patients than males, while no significant gender differences were

  16. Multivariate Time Series Similarity Searching

    PubMed Central

    Wang, Jimin; Zhu, Yuelong; Li, Shijin; Wan, Dingsheng; Zhang, Pengcheng

    2014-01-01

    Multivariate time series (MTS) datasets are very common in various financial, multimedia, and hydrological fields. In this paper, a dimension-combination method is proposed to search similar sequences for MTS. Firstly, the similarity of single-dimension series is calculated; then the overall similarity of the MTS is obtained by synthesizing each of the single-dimension similarity based on weighted BORDA voting method. The dimension-combination method could use the existing similarity searching method. Several experiments, which used the classification accuracy as a measure, were performed on six datasets from the UCI KDD Archive to validate the method. The results show the advantage of the approach compared to the traditional similarity measures, such as Euclidean distance (ED), cynamic time warping (DTW), point distribution (PD), PCA similarity factor (SPCA), and extended Frobenius norm (Eros), for MTS datasets in some ways. Our experiments also demonstrate that no measure can fit all datasets, and the proposed measure is a choice for similarity searches. PMID:24895665

  17. Multivariate time series similarity searching.

    PubMed

    Wang, Jimin; Zhu, Yuelong; Li, Shijin; Wan, Dingsheng; Zhang, Pengcheng

    2014-01-01

    Multivariate time series (MTS) datasets are very common in various financial, multimedia, and hydrological fields. In this paper, a dimension-combination method is proposed to search similar sequences for MTS. Firstly, the similarity of single-dimension series is calculated; then the overall similarity of the MTS is obtained by synthesizing each of the single-dimension similarity based on weighted BORDA voting method. The dimension-combination method could use the existing similarity searching method. Several experiments, which used the classification accuracy as a measure, were performed on six datasets from the UCI KDD Archive to validate the method. The results show the advantage of the approach compared to the traditional similarity measures, such as Euclidean distance (ED), cynamic time warping (DTW), point distribution (PD), PCA similarity factor (SPCA), and extended Frobenius norm (Eros), for MTS datasets in some ways. Our experiments also demonstrate that no measure can fit all datasets, and the proposed measure is a choice for similarity searches. PMID:24895665

  18. Associations of disordered sleep with body fat distribution, physical activity and diet among overweight middle-aged men.

    PubMed

    Tan, Xiao; Alén, Markku; Cheng, Shu Mei; Mikkola, Tuija M; Tenhunen, Jarkko; Lyytikäinen, Arja; Wiklund, Petri; Cong, Fengyu; Saarinen, Antti; Tarkka, Ina; Partinen, Markku; Cheng, Sulin

    2015-08-01

    This cross-sectional study aimed to investigate whether body fat distribution, physical activity levels and dietary intakes are associated with insomnia and/or obstructive sleep apnea among overweight middle-aged men. Participants were 211 Finnish men aged 30-65 years. Among the 163 overweight or obese participants, 40 had insomnia only, 23 had obstructive sleep apnea only, 24 had comorbid insomnia and obstructive sleep apnea and 76 were without sleep disorder. The remaining 48 participants had normal weight without sleep disorder. Fat mass, levels of physical activity and diet were assessed by dual-energy X-ray densitometry, physical activity questionnaire and 3-day food diary, respectively. Among the overweight participants, we found that: (i) groups with sleep disorders had higher fat mass in trunk and android regions than the group without sleep disorder (P = 0.048-0.004); (ii) the insomnia-only group showed a lower level of leisure-time physical activity (436.9 versus 986.5 MET min week(-1) , P = 0.009) and higher intake of saturated fatty acids (14.8 versus 12.7 E%, P = 0.011) than the group without sleep disorder; and (iii) the comorbid group had a lower level of leisure-time physical activity (344.4 versus 986.5 MET min week(-1) , P = 0.007) and lower folate intake (118.9 versus 152.1 μg, P = 0.002) than the group without sleep disorder, which were independent of body mass index. The results suggest that central obesity is associated with insomnia and/or obstructive sleep apnea. In addition, low levels of leisure-time physical activity and poor dietary intakes are related to insomnia or comorbid insomnia and obstructive sleep apnea among overweight men.

  19. Visualizing disease associations: graphic analysis of frequency distributions as a function of age using moving average plots (MAP) with application to Alzheimer's and Parkinson's disease.

    PubMed

    Payami, Haydeh; Kay, Denise M; Zabetian, Cyrus P; Schellenberg, Gerard D; Factor, Stewart A; McCulloch, Colin C

    2010-01-01

    Age-related variation in marker frequency can be a confounder in association studies, leading to both false-positive and false-negative findings and subsequently to inconsistent reproducibility. We have developed a simple method, based on a novel extension of moving average plots (MAP), which allows investigators to inspect the frequency data for hidden age-related variations. MAP uses the standard case-control association data and generates a birds-eye view of the frequency distributions across the age spectrum; a picture in which one can see if, how, and when the marker frequencies in cases differ from that in controls. The marker can be specified as an allele, genotype, haplotype, or environmental factor; and age can be age-at-onset, age when subject was last known to be unaffected, or duration of exposure. Signature patterns that emerge can help distinguish true disease associations from spurious associations due to age effects, age-varying associations from associations that are uniform across all ages, and associations with risk from associations with age-at-onset. Utility of MAP is illustrated by application to genetic and epidemiological association data for Alzheimer's and Parkinson's disease. MAP is intended as a descriptive method, to complement standard statistical techniques. Although originally developed for age patterns, MAP is equally useful for visualizing any quantitative trait.

  20. Self-similar aftershock rates

    NASA Astrophysics Data System (ADS)

    Davidsen, Jörn; Baiesi, Marco

    2016-08-01

    In many important systems exhibiting crackling noise—an intermittent avalanchelike relaxation response with power-law and, thus, self-similar distributed event sizes—the "laws" for the rate of activity after large events are not consistent with the overall self-similar behavior expected on theoretical grounds. This is particularly true for the case of seismicity, and a satisfying solution to this paradox has remained outstanding. Here, we propose a generalized description of the aftershock rates which is both self-similar and consistent with all other known self-similar features. Comparing our theoretical predictions with high-resolution earthquake data from Southern California we find excellent agreement, providing particularly clear evidence for a unified description of aftershocks and foreshocks. This may offer an improved framework for time-dependent seismic hazard assessment and earthquake forecasting.

  1. Self-similar aftershock rates.

    PubMed

    Davidsen, Jörn; Baiesi, Marco

    2016-08-01

    In many important systems exhibiting crackling noise-an intermittent avalanchelike relaxation response with power-law and, thus, self-similar distributed event sizes-the "laws" for the rate of activity after large events are not consistent with the overall self-similar behavior expected on theoretical grounds. This is particularly true for the case of seismicity, and a satisfying solution to this paradox has remained outstanding. Here, we propose a generalized description of the aftershock rates which is both self-similar and consistent with all other known self-similar features. Comparing our theoretical predictions with high-resolution earthquake data from Southern California we find excellent agreement, providing particularly clear evidence for a unified description of aftershocks and foreshocks. This may offer an improved framework for time-dependent seismic hazard assessment and earthquake forecasting. PMID:27627324

  2. Self-similar aftershock rates.

    PubMed

    Davidsen, Jörn; Baiesi, Marco

    2016-08-01

    In many important systems exhibiting crackling noise-an intermittent avalanchelike relaxation response with power-law and, thus, self-similar distributed event sizes-the "laws" for the rate of activity after large events are not consistent with the overall self-similar behavior expected on theoretical grounds. This is particularly true for the case of seismicity, and a satisfying solution to this paradox has remained outstanding. Here, we propose a generalized description of the aftershock rates which is both self-similar and consistent with all other known self-similar features. Comparing our theoretical predictions with high-resolution earthquake data from Southern California we find excellent agreement, providing particularly clear evidence for a unified description of aftershocks and foreshocks. This may offer an improved framework for time-dependent seismic hazard assessment and earthquake forecasting.

  3. Effect of data length and bin numbers on distribution entropy (DistEn) measurement in analyzing healthy aging.

    PubMed

    Udhayakumar, Radhagayathri K; Karmakar, Chandan; Peng Li; Palaniswami, Marimuthu

    2015-01-01

    Complexity analysis of a given time series is executed using various measures of irregularity, the most commonly used being Approximate entropy (ApEn), Sample entropy (SampEn) and Fuzzy entropy (FuzzyEn). However, the dependence of these measures on the critical parameter of tolerance `r' leads to precarious results, owing to random selections of r. Attempts to eliminate the use of r in entropy calculations introduced a new measure of entropy namely distribution entropy (DistEn) based on the empirical probability distribution function (ePDF). DistEn completely avoids the use of a variance dependent parameter like r and replaces it by a parameter M, which corresponds to the number of bins used in the histogram to calculate it. When tested for synthetic data, M has been observed to produce a minimal effect on DistEn as compared to the effect of r on other entropy measures. Also, DistEn is said to be relatively stable with data length (N) variations, as far as synthetic data is concerned. However, these claims have not been analyzed for physiological data. Our study evaluates the effect of data length N and bin number M on the performance of DistEn using both synthetic and physiologic time series data. Synthetic logistic data of `Periodic' and `Chaotic' levels of complexity and 40 RR interval time series belonging to two groups of healthy aging population (young and elderly) have been used for the analysis. The stability and consistency of DistEn as a complexity measure as well as a classifier have been studied. Experiments prove that the parameters N and M are more influential in deciding the efficacy of DistEn performance in the case of physiologic data than synthetic data. Therefore, a generalized random selection of M for a given data length N may not always be an appropriate combination to yield good performance of DistEn for physiologic data.

  4. Biosimilar Insulins: How Similar is Similar?

    PubMed Central

    Heinemann, Lutz; Hompesch, Marcus

    2011-01-01

    Biosimilar insulins (BIs) are viewed as commercially attractive products by a number of companies. In order to obtain approval in the European Union or the United States, where there is not a single BI currently on the market, a manufacturer needs to demonstrate that a given BI has a safety and efficacy profile that is similar to that of the “original” insulin formulation that is already on the market. As trivial as this may appear at first glance, it is not trivial at all for a good number of reasons that will be discussed in this commentary. As with protein manufacturing, modifications in the structure of the insulin molecule can take place (which can have serious consequences for the biological effects induced), so a rigid and careful assessment is absolutely necessary. The example of Marvel's failed application with the European Medicines Agency provides insights into the regulatory and clinical challenges surrounding the matter of BI. Although a challenging BI approval process might be regarded as a hurdle to keep companies out of certain markets, it is fair to say that the potential safety and efficacy issues surrounding BI are substantial and relevant and do warrant a careful and evidence-driven approval process. PMID:21722590

  5. Distribution and partial characterization of seasonally expressed proteins in different aged shoots and roots of 'Loring' peach (Prunus persica).

    PubMed

    Wisniewski, Michael; Bassett, Carole; Arora, Rajeev

    2004-03-01

    During autumnal leaf senescence, leaf nitrogen in deciduous trees is translocated to storage sites, especially bark and xylem tissues. Proteins that accumulate in large amounts in bark and xylem in winter and are absent from these organs in summer are called storage proteins, and are believed to be vehicles for storing nitrogen reserves. These reserves are important for spring growth and help trees tolerate or recover from both abiotic and biotic stresses. Based on seasonal patterns of accumulation, we previously identified three storage proteins with molecular masses of 60, 19 and 16 kDa in bark tissues of 'Loring' peach (Prunus persica (L.) Batsch). To characterize the distribution of these proteins in different-aged tissues and to determine if they have any function other than nitrogen storage, we examined their seasonal distribution in bark tissues of current-year and 1-year-old shoots, scaffold branches, main trunks and 4-5-year-old roots of 'Loring' peach. Verification of protein identity was based on molecular mass and reactions with antibodies directed against each specific protein. Protein distribution was variable. For all three proteins, the greatest amount was present in mid-winter in current-year and 1-year-old shoots. These tissues also showed the greatest seasonal variation in the amount of protein present. The 16 kDa protein was present only in the youngest shoots, whereas the 19 kDa protein was present in all tissues examined. The 60 kDa protein was absent in root tissue. The amino acid composition and sequence of each protein were determined. The 60 kDa protein was identified as a dehydrin, and the 19 kDa protein appeared to be related to a family of allergen proteins in Rosaceous plants, some members of which are associated with pathogenesis-related proteins. The amino acid sequence of the 16 kDa protein appeared to have no homology with any proteins in the SwissProt database. Therefore, it is likely that the 16 kDa protein, in a strict sense, is

  6. Quaternary sea level high-stand deposits of the southeast U.S. Atlantic Coastal Plain: Age, distribution, and implications.

    NASA Astrophysics Data System (ADS)

    Poirier, R. K.; Cronin, T. M.; Ghaleb, B.; Portell, R.; Hillaire-Marcel, C.; Wehmiller, J. F.; Thompson, W. G.; Oches, E. A.; Willard, D. A.; Katz, M. E.

    2015-12-01

    Emerged Quaternary paleo-shorelines and marine deposits provide a more direct way to reconstruct and analyze sea-level variability than methods using oxygen isotope analyses of deep ocean benthic foraminifera. New Uranium-series dates on fossil corals (primarily Astrangia spp. and Septastrea spp.) combined with previously published dates have allowed us to constrain the age, elevation, and geographical distribution of marine sediments deposited in the United States Atlantic Coastal Plain (ACP) from Virginia to Florida during periods of past high relative sea level (SL). We present new dates from deposits (VA/NC: Tabb/Norfolk, Nassawadox, & Omar Formations; SC: Wando, Socastee, & Canepatch Formations; FL: Anastasia, Ft. Thompson, & Bermont Formations) representing interglacial high-stands during Marine Isotope Stages (MIS) 5, 7, 9, and 11. In addition, we incorporate stratigraphic, marine micropaleontologic, and palynologic records with our SL chronology to reconstruct a more complete history of middle-to-late Pleistocene interglacial climates of the ACP. Ultimately, these results will test modeled sea-level fingerprint studies based on various melting scenarios of the Greenland and/or Antarctic ice sheets.

  7. Purkinje cell age-distribution in fissures and in foliar crowns: a comparative study in the weaver cerebellum.

    PubMed

    Martí, Joaquín; Santa-Cruz, M C; Bayer, Shirley A; Ghetti, Bernardino; Hervás, José P

    2007-12-01

    Generation and settling of Purkinje cells (PCs) are investigated in the weaver mouse cerebellum in order to determine possible relationships with the fissuration pattern. Tritiated thymidine was supplied to pregnant females at the time that these neurons were being produced. Autoradiography was then applied on brain sections obtained from control and weaver offspring at postnatal (P) day 90. This makes it possible to assess the differential survival of neurons born at distinct embryonic times on the basis of the proportion of labeled cells located at the two foliar compartments: fissures and foliar crowns. Our data show that throughout the surface contour of the vermal lobes, generative programs of PCs were close between wild type and homozygous weaver. Similar data were found in the lobules of the lateral hemisphere. On the other hand, the loss of PCs in weaver cerebella can be related to foliar concavities or convexities depending on the vermal lobe or the hemispheric lobule studied. Lastly, we have obtained evidence that late-generated PCs of both normal and mutant mice were preferentially located in fissures. These quantitative relationships lead us to propose a model in which the final distribution of PCs through the vermal contour would be coupled to two factors: the cortical fissuration patterning and a "time-sequential effect" of weaver mutation.

  8. Age- and direction-related adaptations of lumbar vertebral trabecular bone with respect to apparent stiffness and tissue level stress distribution

    NASA Astrophysics Data System (ADS)

    Gong, He; Fan, Yubo; Zhang, Ming; Qin, Ling

    2009-02-01

    The objective of this study was to study the age-related adaptation of lumbar vertebral trabecular bone at the apparent level, as well as the tissue level in three orthogonal directions. Ninety trabecular specimens were obtained from six normal L4 vertebral bodies of six male cadavers in two age groups, three aged 62 years and three aged 69 years, and were scanned using a high-resolution micro-computed tomography (micro-CT) system, then converted to micro-finite element models to do micro-finite element analyses. The relationship between apparent stiffness and bone volume fraction, and the tissue level von Mises stress distribution for each trabecular specimen when compressed separately in the longitudinal direction, medial-lateral and anterior-posterior directions (transverse directions) were derived and compared between two age groups. The results showed that at the apparent level, trabecular bones from 69-year group had stiffer bone structure relative to their volume fractions in all three directions, and in both age groups, changes in bone volume fraction could explain more variations in apparent stiffness in the longitudinal direction than the transverse directions; at the tissue level, aging had little effect on the tissue von Mises stress distributions for the compressions in all the three directions. The novelty of the present study was that it provided quantitative assessments on the age and direction-related adaptation of Chinese male lumbar vertebral trabecular bone from two different levels: stiffness at the apparent level and stress distribution at the tissue level. It may help to understand the failure mechanisms and fracture risks of vertebral body associated with aging and direction for the prevention of fracture risks in elder individuals.

  9. U-Th age distribution of coral fragments from multiple rubble ridges within the Frankland Islands, Great Barrier Reef: Implications for past storminess history

    NASA Astrophysics Data System (ADS)

    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

  10. ESTROGEN AND AGING AFFECT THE SYNAPTIC DISTRIBUTION OF ESTROGEN RECEPTOR BETA-IMMUNOREACTIVITY IN THE CA1 REGION OF FEMALE RAT HIPPOCAMPUS

    PubMed Central

    Waters, Elizabeth M.; Yildirim, Murat; Janssen, William G.M.; Lou, W.Y. Wendy; McEwen, Bruce S.; Morrison, John H.; Milner, Teresa A.

    2010-01-01

    Estradiol (E) mediates increased synaptogenesis in the hippocampal CA1 stratum radiatum (sr) and enhances memory in young and some aged female rats, depending on dose and age. Young females rats express more estrogen receptor α (ERα) immunolabeling in CA1sr spine synapse complexes than aged rats and ERα regulation is E sensitive in young but not aged rats. The current study examined whether estrogen receptor β (ERβ) expression in spine synapse complexes may be altered by age or E treatment. Young (3–4 months) and aged (22–23 months) female rats were ovariectomized 7 days prior to implantation of silastic capsules containing either vehicle (cholesterol) or E (10% in cholesterol) for 2 days. ERβ immunoreactivity (ir) in CA1sr was quantitatively analyzed using post-embedding electron microscopy. ERβ-ir was more prominent postsynaptically than presynaptically and both age and E treatment affected its synaptic distribution. While age decreased the spine synaptic complex localization of ERβ-ir (i.e., within 60 nm of the pre- and post-synaptic membranes), E treatment increased synaptic ERβ in both young and aged rats. In addition, the E treatment, but not age, increased dendritic shaft labeling. This data demonstrates that like ERα the levels of ERβ-ir decrease in CA1 axospinous synapses with age, however, unlike ERα the levels of ERβ-ir increase in these synapses in both young and aged rats in response to E. This suggests that synaptic ERβ may be a more responsive target to E, particularly in aged females. PMID:20875808

  11. A Modern Analog to the Depositional Age Problem: Zircon and Apatite Fission Track and U-Pb Age Distributions by LA-ICP-MS

    NASA Astrophysics Data System (ADS)

    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 <44 Ma were observed. Interestingly, not one of the river samples yielded zircon U-Pb ages near 0 Ma, despite all three catchment areas having received significant ash from Mt. St. Helens in 1980, and Mount 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.

  12. Time-slice maps showing age, distribution, and style of deformation in Alaska north of 60° N.

    USGS Publications Warehouse

    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

  13. Gender similarities and differences.

    PubMed

    Hyde, Janet Shibley

    2014-01-01

    Whether men and women are fundamentally different or similar has been debated for more than a century. This review summarizes major theories designed to explain gender differences: evolutionary theories, cognitive social learning theory, sociocultural theory, and expectancy-value theory. The gender similarities hypothesis raises the possibility of theorizing gender similarities. Statistical methods for the analysis of gender differences and similarities are reviewed, including effect sizes, meta-analysis, taxometric analysis, and equivalence testing. Then, relying mainly on evidence from meta-analyses, gender differences are reviewed in cognitive performance (e.g., math performance), personality and social behaviors (e.g., temperament, emotions, aggression, and leadership), and psychological well-being. The evidence on gender differences in variance is summarized. The final sections explore applications of intersectionality and directions for future research.

  14. The Relationship of Loss, Mean Age of Air and the Distribution of CFC's to Stratospheric Circulation and Implications for Atmospheric Lifetimes

    NASA Technical Reports Server (NTRS)

    Douglas, A. R.; Stolarski, R. S.; Schoeberl, M. R.; Jackman, C. H.; Gupta, M. L.; Newman, P. A.; Nielsen, J. E.; Fleming, E. L.

    2008-01-01

    Model-derived estimates of the annually integrated destruction and lifetime for various ozone depleting substances (ODSs) depend on the simulated stratospheric transport and mixing in the global model used to produce the estimate. Observations in the middle and high latitude lower stratosphere show that the mean age of an air parcel (i.e., the time since its stratospheric entry) is related to the fractional release for the ODs (i.e., the amount of the ODS that has been destroyed relative to the amount at the time of stratospheric entry). We use back trajectory calculations to produce an age spectrum, and explain the relationship between the mean age and the fractional release by showing that older elements in the age spectrum have experienced higher altitudes and greater ODs destruction than younger elements. In our study, models with faster circulations produce distributions for the age-of-air that are 'young' compared to a distribution derived from observations. These models also fail to reproduce the observed relationship between the mean age of air and the fractional release. Models with slower circulations produce both realistic distributions for mean age and a realistic relationship between mean age and fractional release. These models also produce a CFCl3 lifetime of approximately 56 years, longer than the 45 year lifetime used to project future mixing ratios. We find that the use of flux boundary conditions in assessment models would have several advantages, including consistency between ODS evolution and simulated loss even if the simulated residual circulation changes due to climate change.

  15. MitoTimer probe reveals the impact of autophagy, fusion, and motility on subcellular distribution of young and old mitochondrial protein and on relative mitochondrial protein age

    PubMed Central

    Ferree, Andrew W; Trudeau, Kyle; Zik, Eden; Benador, Ilan Y; Twig, Gilad; Gottlieb, Roberta A; Shirihai, Orian S

    2013-01-01

    To study mitochondrial protein age dynamics, we targeted a time-sensitive fluorescent protein, MitoTimer, to the mitochondrial matrix. Mitochondrial age was revealed by the integrated portions of young (green) and old (red) MitoTimer protein. Mitochondrial protein age was dependent on turnover rates as pulsed synthesis, decreased import, or autophagic inhibition all increased the proportion of aged MitoTimer protein. Mitochondrial fusion promotes the distribution of young mitochondrial protein across the mitochondrial network as cells lacking essential fusion genes Mfn1 and Mfn2 displayed increased heterogeneity in mitochondrial protein age. Experiments in hippocampal neurons illustrate that the distribution of older and younger mitochondrial protein within the cell is determined by subcellular spatial organization and compartmentalization of mitochondria into neurites and soma. This effect was altered by overexpression of mitochondrial transport protein, RHOT1/MIRO1. Collectively our data show that distribution of young and old protein in the mitochondrial network is dependent on turnover, fusion, and transport. PMID:24149000

  16. Mortality estimates from ovarian age distributions of the tsetse fly Glossina pallidipes Austen sampled in Zimbabwe suggest the need for new analytical approaches

    PubMed Central

    HARGROVE, JOHN W.; ACKLEY, SARAH F.

    2016-01-01

    Mortality estimates are central to understanding tsetse fly population dynamics, but are difficult to acquire from wild populations. They can be obtained from age distribution data but, with limited data, it is unclear whether the assumptions required to make the estimates are satisfied and, if not, how violations affect the estimates. We evaluate the assumptions required for existing mortality estimation techniques using long-term longitudinal ovarian dissection data from 144,106 female tsetse, Glossina pallidipes Austen, captured in Zimbabwe between 1988 and 1999. At the end of the hot dry season each year, mean ovarian ages peaked, and maximum likelihood mortality estimates declined to low levels, contrary to mark-recapture estimates, suggesting violations of the assumptions underlying the estimation technique. We demonstrate that age distributions are seldom stable for G. pallidipes at our study site, and hypothesize that this is a consequence of a disproportionate increase in the mortality of pupae and young adults at the hottest times of the year. Assumptions of age-independent mortality and capture probability are also violated, the latter bias varying with capture method and with pregnancy and nutritional status. As a consequence, mortality estimates obtained from ovarian dissection data are unreliable. To overcome these problems we suggest simulating female tsetse populations, using dynamical modelling techniques that make no assumptions about the stability of the age distribution. PMID:25804211

  17. Age, Distribution, and Style of Deformation in Alaska North of 60°N: Implications for Assembly of Alaska

    NASA Astrophysics Data System (ADS)

    Moore, T. E.; Box, S. E.

    2015-12-01

    The structural architecture of Alaska is the product of a complex history of deformation along both the Cordilleran and Arctic margins of North America through interactions with ocean plates and with continental elements of Laurentia, Siberia, and Baltica. We use geological constraints to assign areal deformation to 14 time intervals and map their distributions in Alaska. Alaska can be divided into three domains with differing histories of deformation. The northern domain experienced the Early Cretaceous Brookian orogeny, an oceanic arc-continent collisional orogeny, followed by a mid-Cretaceous extensional overprint. Opening of the oceanic Canada Basin rifted the orogen from the Canadian Arctic margin, producing the bent trends of the orogen. The second domain constitutes the Phanerozoic Peninsular-Wrangellia-Alexander arc terrane and its paired Mesozoic accretionary prisms. Its structural history is unrelated to domains to the north until a shared history of Late Cretaceous deformation. The third domain, situated between the first two domains and roughly bounded by the Cenozoic dextral Denali and Tintina faults, includes the Yukon Composite terrane (Laurentian origin) and the large Farewell (Baltica origin) terrane. These terranes are not linked until Late Cretaceous sedimentary overlap, but we have not identified a shared deformation between these two terranes that might mark their juxtaposition by collisional processes. Similar early Late Cretaceous sedimentary linkages stitch the northern and central domains. Late Late Cretaceous folding and thrusting across much of Alaska south of the Brooks Range correlates temporally with the collision of the southern domain with the remainder of Alaska. Early Cenozoic shortening is mild across much of the state but is significant in the Brooks Range, and correlates in time with dextral faulting, ridge subduction, and rotation of western Alaska. Late Cenozoic shortening is significant in southern Alaska inboard of the

  18. Estimating Age Distributions of Base Flow in Watersheds Underlain by Single and Dual Porosity Formations Using Groundwater Transport Simulation and Weighted Weibull Functions

    NASA Astrophysics Data System (ADS)

    Sanford, W. E.

    2015-12-01

    Age distributions of base flow to streams are important to estimate for predicting the timing of water-quality responses to changes in distributed inputs of nutrients or pollutants at the land surface. Simple models of shallow aquifers will predict exponential age distributions, but more realistic 3-D stream-aquifer geometries will cause deviations from an exponential curve. In addition, in fractured rock terrains the dual nature of the effective and total porosity of the system complicates the age distribution further. In this study shallow groundwater flow and advective transport were simulated in two regions in the Eastern United States—the Delmarva Peninsula and the upper Potomac River basin. The former is underlain by layers of unconsolidated sediment, while the latter consists of folded and fractured sedimentary rocks. Transport of groundwater to streams was simulated using the USGS code MODPATH within 175 and 275 watersheds, respectively. For the fractured rock terrain, calculations were also performed along flow pathlines to account for exchange between mobile and immobile flow zones. Porosities at both sites were calibrated using environmental tracer data (3H, 3He, CFCs and SF6) in wells and springs, and with a 30-year tritium record from the Potomac River. Carbonate and siliciclastic rocks were calibrated to have mobile porosity values of one and six percent, and immobile porosity values of 18 and 12 percent, respectively. The age distributions were fitted to Weibull functions. Whereas an exponential function has one parameter that controls the median age of the distribution, a Weibull function has an extra parameter that controls the slope of the curve. A weighted Weibull function was also developed that potentially allows for four parameters, two that control the median age and two that control the slope, one of each weighted toward early or late arrival times. For both systems the two-parameter Weibull function nearly always produced a substantially

  19. A comparison of the age distributions in the dengue hemorrhagic fever epidemics in Santiago de Cuba (1997) and Thailand (1998).

    PubMed

    Pongsumpun, P; Yoksan, S; Tan, I M

    2002-06-01

    The age profiles of the infected populations of two dengue hemorrhagic fever (DHF) epidemics, the 1997 epidemic, in Santiago de Cuba and the 1998 epidemic in Thailand, are compared. Using an age-structured model of disease transmission, the dependence of the forces of infection on age was determined for each epidemic. The difference in the behavior of the two epidemics and the role of primary and secondary infection in the development of DHF are discussed.

  20. Solution structure of the yeast URN1 splicing factor FF domain: comparative analysis of charge distributions in FF domain structures-FFs and SURPs, two domains with a similar fold.

    PubMed

    Bonet, Roman; Ramirez-Espain, Ximena; Macias, Maria J

    2008-12-01

    FF domains are present in three protein families: the splicing factors formin binding protein 11 (FBP11), Prp40, and URN1, the transcription factor CA150, and the p190RhoGTPase-related proteins. This simplicity in distribution, however, is contrasted by the difficulty in defining their biological role. At best, the group of ligand FF domains can bind to form a motley crew with binding reports pointing also to negative/aromatic sequences, the tetratricopeptide repeat, the transcription factor TFII-I and even to RNA. To expand our knowledge on the FF domain, we selected the FF domain present in the URN1 yeast splicing factor as the subject for structural studies. The URN1 protein is one of the two known proteins containing only one FF domain, making it the most simplified representative of FF domain-containing splicing factors. The solution structure reveals that the domain adopts the classical FF fold, with a distinctive negatively charged patch on its surface. All available FF structures have a well-conserved fold but variable electrostatic patches on their surfaces. These patches are unconserved, even for domains with similar pK(a)s. To investigate potential binding sites in FF domains, we performed structural comparisons to other proteins with similar folds. In addition to the structures detected by SCOP, we included SURP domains, which also adopt the alpha1-alpha2-3(10)-alpha3 architecture. We observed that the main difference between all these structures resides in the orientation of the second helix. Remarkably, in DEK, SURP, and Prp40FF1 structures (the exception is the FBP11FF1 domain), the second helix participates in ligand recognition. Furthermore, SURP and Prp40FF1 binding sites also include the 3(10) helix, which forms a partially exposed hydrophobic cavity. This cavity is also present in at least CA150FF1 and FF2 structures. Thus, as with WW domains, the FF fold seems to have developed binding-site variations to accommodate an abundant and variable set

  1. The Qualitative Similarity Hypothesis

    ERIC Educational Resources Information Center

    Paul, Peter V.; Lee, Chongmin

    2010-01-01

    Evidence is presented for the qualitative similarity hypothesis (QSH) with respect to children and adolescents who are d/Deaf or hard of hearing. The primary focus is on the development of English language and literacy skills, and some information is provided on the acquisition of English as a second language. The QSH is briefly discussed within…

  2. Diel distribution of age-0 largemouth bass, Micropterus salmoides, in B. E. Jordan Lake, North Carolina (USA) and its relation to cover

    USGS Publications Warehouse

    Irwin, E.R.; Noble, R.L.

    2000-01-01

    We used prepositioned area electrofishers (PAEs, 10X1.5 m) to assess diel differences in distribution of age-0 largemouth bass, Micropterus salmoides, in August 1992-1993 in a paired sampling design. PAEs were placed parallel to shore in an embayment of an unvegetated reservoir (B. E. Jordan Lake, North Carolina, USA). The catch per unit effort (CPUE=fish/PAE) was significantly higher at night than during the day in both years, indicating that age-0 largemouth bass exhibit nocturnal inshore movements. Age-0 largemouth bass captured inshore during day were smaller than those captured at night, indicating that movement patterns may change ontogenetically. Inshore-offshore movements of age-0 largemouth bass were significantly reduced in the presence of cover, suggesting that diel movements were influenced by specific habitat components. Diel movements likely were related to foraging, resting and predator avoidance behavior and could affect population dynamics and introduce bias in assessment programs.

  3. Tumour control probability derived from dose distribution in homogeneous and heterogeneous models: assuming similar pharmacokinetics, 125Sn-177Lu is superior to 90Y-177Lu in peptide receptor radiotherapy

    NASA Astrophysics Data System (ADS)

    Walrand, Stephan; Hanin, François-Xavier; Pauwels, Stanislas; Jamar, François

    2012-07-01

    Clinical trials on 177Lu-90Y therapy used empirical activity ratios. Radionuclides (RN) with larger beta maximal range could favourably replace 90Y. Our aim is to provide RN dose-deposition kernels and to compare the tumour control probability (TCP) of RN combinations. Dose kernels were derived by integration of the mono-energetic beta-ray dose distributions (computed using Monte Carlo) weighted by their respective beta spectrum. Nine homogeneous spherical tumours (1-25 mm in diameter) and four spherical tumours including a lattice of cold, but alive, spheres (1, 3, 5, 7 mm in diameter) were modelled. The TCP for 93Y, 90Y and 125Sn in combination with 177Lu in variable proportions (that kept constant the renal cortex biological effective dose) were derived by 3D dose kernel convolution. For a mean tumour-absorbed dose of 180 Gy, 2 mm homogeneous tumours and tumours including 3 mm diameter cold alive spheres were both well controlled (TCP > 0.9) using a 75-25% combination of 177Lu and 90Y activity. However, 125Sn-177Lu achieved a significantly better result by controlling 1 mm-homogeneous tumour simultaneously with tumours including 5 mm diameter cold alive spheres. Clinical trials using RN combinations should use RN proportions tuned to the patient dosimetry. 125Sn production and its coupling to somatostatin analogue appear feasible. Assuming similar pharmacokinetics 125Sn is the best RN for combination with 177Lu in peptide receptor radiotherapy justifying pharmacokinetics studies in rodent of 125Sn-labelled somatostatin analogues.

  4. Applying ligands profiling using multiple extended electron distribution based field templates and feature trees similarity searching in the discovery of new generation of urea-based antineoplastic kinase inhibitors.

    PubMed

    Dokla, Eman M; Mahmoud, Amr H; Elsayed, Mohamed S A; El-Khatib, Ahmed H; Linscheid, Michael W; Abouzid, Khaled A

    2012-01-01

    This study provides a comprehensive computational procedure for the discovery of novel urea-based antineoplastic kinase inhibitors while focusing on diversification of both chemotype and selectivity pattern. It presents a systematic structural analysis of the different binding motifs of urea-based kinase inhibitors and the corresponding configurations of the kinase enzymes. The computational model depends on simultaneous application of two protocols. The first protocol applies multiple consecutive validated virtual screening filters including SMARTS, support vector-machine model (ROC = 0.98), Bayesian model (ROC = 0.86) and structure-based pharmacophore filters based on urea-based kinase inhibitors complexes retrieved from literature. This is followed by hits profiling against different extended electron distribution (XED) based field templates representing different kinase targets. The second protocol enables cancericidal activity verification by using the algorithm of feature trees (Ftrees) similarity searching against NCI database. Being a proof-of-concept study, this combined procedure was experimentally validated by its utilization in developing a novel series of urea-based derivatives of strong anticancer activity. This new series is based on 3-benzylbenzo[d]thiazol-2(3H)-one scaffold which has interesting chemical feasibility and wide diversification capability. Antineoplastic activity of this series was assayed in vitro against NCI 60 tumor-cell lines showing very strong inhibition of GI(50) as low as 0.9 uM. Additionally, its mechanism was unleashed using KINEX™ protein kinase microarray-based small molecule inhibitor profiling platform and cell cycle analysis showing a peculiar selectivity pattern against Zap70, c-src, Mink1, csk and MeKK2 kinases. Interestingly, it showed activity on syk kinase confirming the recent studies finding of the high activity of diphenyl urea containing compounds against this kinase. Allover, the new series, which is based on

  5. Age Distribution and Determinants of Invasive Cervical Cancer in a “Screen-and-Treat” Program Integrated With HIV/AIDS Care in Zambia

    PubMed Central

    Kapambwe, Sharon; Sahasrabuddhe, Vikrant V.; Blevins, Meridith; Mwanahamuntu, Mulindi H.; Mudenda, Victor; Shepherd, Bryan E.; Chibwesha, Carla J.; Pfaendler, Krista S.; Hicks, Michael L.; Vermund, Sten H.; Stringer, Jeffrey S. A.; Parham, Groesbeck P.

    2016-01-01

    Background Cervical cancer screening efforts linked to HIV/ AIDS care programs are being expanded across sub-Saharan Africa. Evidence on the age distribution and determinants of invasive cervical cancer (ICC) cases detected in such programs is limited. Methods We analyzed program operations data from the Cervical Cancer Prevention Program in Zambia, the largest public sector programs of its kind in sub-Saharan Africa. We examined age distribution patterns by HIV serostatus of histologically confirmed ICC cases and used multivariable logistic regression to evaluate independent risk factors for ICC among younger (≤35 years) and older (>35 years) women. Results Between January 2006 and April 2010, of 48,626 women undergoing screening, 571 (1.2%) were diagnosed with ICC, including 262 (46%) HIV seropositive (median age: 35 years), 131 (23%) HIV seronegative (median age: 40 years), and 178 (31%) of unknown HIV serostatus (median age: 38 years). Among younger (≤35 years) women, being HIV seropositive was associated with a 4-fold higher risk of ICC [adjusted odds ratio = 4.1 (95% confidence interval: 2.8, 5.9)] than being HIV seronegative. The risk of ICC increased with increasing age among HIV-seronegative women and women with unknown HIV serostatus, but among HIV-seropositive women, the risk peaked around age 35 and non-significantly declined with increasing ages. Other factors related to ICC included being married (vs. being unmarried/widowed) in both younger and older women, and with having 2+ (vs. ≤1) lifetime sexual partners among younger women. Conclusions HIV infection seems to have increased the risk of cervical cancer among younger women in Zambia, pointing to the urgent need for expanding targeted screening interventions. PMID:26322673

  6. Distribution of age-classes of striped weakfish ( Cynoscion guatucupa) along an estuarine-marine gradient: Correlations with the environmental parameters

    NASA Astrophysics Data System (ADS)

    Jaureguizar, Andres J.; Ruarte, Claudio; Guerrero, Raúl A.

    2006-03-01

    The age-class distribution of the striped weakfish ( Cynoscion guatucupa) and its relationship with environmental factors were evaluated along the coast between Argentina and Uruguay, including the Río de la Plata estuary (36° S, 56° W). One hundred and seven stations were sampled between 2001 and 2003 during autumn, winter, and spring. Multivariate analyses (Cluster and MDS) were used to define sampling station groups, and a BIO-ENV procedure used to estimate the association of stations with environmental factors (depth, stratification, temperature and salinity of surface and bottom waters). The BIO-ENV procedure indicated that the salinity during autumn-winter and the temperature in spring had a significant influence on the spatial age-class pattern. The proportion of the youngest age-classes decreased from the estuarine area to the marine coastal area, except during spring where it showed the reverse pattern. The older age-classes inhabited the marine coastal area (more saline) toward the deepest zone, while the youngest individuals inhabited the outer estuarine area. Examination of the coastal circulation associated with the spatial distribution, and of the age-class frequency in the estuarine and marine coastal area, suggested that spawning took place in inshore coastal waters at very shallow depths.

  7. Indexing Similar DNA Sequences

    NASA Astrophysics Data System (ADS)

    Huang, Songbo; Lam, T. W.; Sung, W. K.; Tam, S. L.; Yiu, S. M.

    To study the genetic variations of a species, one basic operation is to search for occurrences of patterns in a large number of very similar genomic sequences. To build an indexing data structure on the concatenation of all sequences may require a lot of memory. In this paper, we propose a new scheme to index highly similar sequences by taking advantage of the similarity among the sequences. To store r sequences with k common segments, our index requires only O(n + NlogN) bits of memory, where n is the total length of the common segments and N is the total length of the distinct regions in all texts. The total length of all sequences is rn + N, and any scheme to store these sequences requires Ω(n + N) bits. Searching for a pattern P of length m takes O(m + m logN + m log(rk)psc(P) + occlogn), where psc(P) is the number of prefixes of P that appear as a suffix of some common segments and occ is the number of occurrences of P in all sequences. In practice, rk ≤ N, and psc(P) is usually a small constant. We have implemented our solution and evaluated our solution using real DNA sequences. The experiments show that the memory requirement of our solution is much less than that required by BWT built on the concatenation of all sequences. When compared to the other existing solution (RLCSA), we use less memory with faster searching time.

  8. Comparison of hydrological similarity measures

    NASA Astrophysics Data System (ADS)

    Rianna, Maura; Ridolfi, Elena; Manciola, Piergiorgio; Napolitano, Francesco; Russo, Fabio

    2016-04-01

    The use of a traditional at site approach for the statistical characterization and simulation of spatio-temporal precipitation fields has a major recognized drawback. Indeed, the weakness of the methodology is related to the estimation of rare events and it involves the uncertainty of the at-site sample statistical inference, because of the limited length of records. In order to overcome the lack of at-site observations, regional frequency approach uses the idea of substituting space for time to estimate design floods. The conventional regional frequency analysis estimates quantile values at a specific site from multi-site analysis. The main idea is that homogeneous sites, once pooled together, have similar probability distribution curves of extremes, except for a scaling factor. The method for pooling groups of sites can be based on geographical or climatological considerations. In this work the region of influence (ROI) pooling method is compared with an entropy-based one. The ROI is a flexible pooling group approach which defines for each site its own "region" formed by a unique set of similar stations. The similarity is found through the Euclidean distance metric in the attribute space. Here an alternative approach based on entropy is introduced to cluster homogeneous sites. The core idea is that homogeneous sites share a redundant (i.e. similar) amount of information. Homogeneous sites are pooled through a hierarchical selection based on the mutual information index (i.e. a measure of redundancy). The method is tested on precipitation data in Central Italy area.

  9. Evaluation of an Education, Restraint Distribution, and Fitting Program to Promote Correct Use of Age-Appropriate Child Restraints for Children Aged 3 to 5 Years: A Cluster Randomized Trial

    PubMed Central

    Hunter, Kate; Brown, Julie; Simpson, Judy M.; Bilston, Lynne E.; Elliott, Maureen; Stevenson, Mark; Ivers, Rebecca Q.

    2012-01-01

    Objectives. We evaluated an education, distribution, and fitting program for increasing age-appropriate and correct child restraint use. Methods. We performed a cluster randomized trial involving 28 early childhood education centers in low socioeconomic status areas in Sydney, Australia. The main outcome was optimal restraint use defined as age-appropriate restraints, installed into the vehicle correctly and used correctly. Results. One service withdrew after randomization, so data are presented for 689 child passengers, aged 3 to 5 years, from 27 centers. More children attending intervention centers were optimally restrained (43% vs 31%; P = .01; allowing for clustering). More 3-year-olds were using forward-facing seats rather than booster seats, more 4- to 5-year-olds were using booster seats instead of seat belts alone, and there were fewer errors in use at intervention centers. Among non–English-speaking families, more children attending intervention centers were optimally restrained (43% vs 17%; P = .002; allowing for clustering). Conclusions. The program increased use of age-appropriate restraints and correct use of restraints, which translates to improved crash injury protection. Multifaceted education, seat distribution, and fitting enhanced legislation effects, and the effect size was larger in non–English-speaking families. PMID:23078492

  10. Applying Ligands Profiling Using Multiple Extended Electron Distribution Based Field Templates and Feature Trees Similarity Searching in the Discovery of New Generation of Urea-Based Antineoplastic Kinase Inhibitors

    PubMed Central

    Dokla, Eman M.; Mahmoud, Amr H.; Elsayed, Mohamed S. A.; El-Khatib, Ahmed H.; Linscheid, Michael W.; Abouzid, Khaled A.

    2012-01-01

    This study provides a comprehensive computational procedure for the discovery of novel urea-based antineoplastic kinase inhibitors while focusing on diversification of both chemotype and selectivity pattern. It presents a systematic structural analysis of the different binding motifs of urea-based kinase inhibitors and the corresponding configurations of the kinase enzymes. The computational model depends on simultaneous application of two protocols. The first protocol applies multiple consecutive validated virtual screening filters including SMARTS, support vector-machine model (ROC = 0.98), Bayesian model (ROC = 0.86) and structure-based pharmacophore filters based on urea-based kinase inhibitors complexes retrieved from literature. This is followed by hits profiling against different extended electron distribution (XED) based field templates representing different kinase targets. The second protocol enables cancericidal activity verification by using the algorithm of feature trees (Ftrees) similarity searching against NCI database. Being a proof-of-concept study, this combined procedure was experimentally validated by its utilization in developing a novel series of urea-based derivatives of strong anticancer activity. This new series is based on 3-benzylbenzo[d]thiazol-2(3H)-one scaffold which has interesting chemical feasibility and wide diversification capability. Antineoplastic activity of this series was assayed in vitro against NCI 60 tumor-cell lines showing very strong inhibition of GI50 as low as 0.9 uM. Additionally, its mechanism was unleashed using KINEX™ protein kinase microarray-based small molecule inhibitor profiling platform and cell cycle analysis showing a peculiar selectivity pattern against Zap70, c-src, Mink1, csk and MeKK2 kinases. Interestingly, it showed activity on syk kinase confirming the recent studies finding of the high activity of diphenyl urea containing compounds against this kinase. Allover, the new series, which is

  11. The Distribution of SIgA and IgG Antibody-Secreting Cells in the Small Intestine of Bactrian Camels (Camelus bactrianus) of Different Ages

    PubMed Central

    Zhang, Wang-Dong; Wang, Wen-Hui; Jia, Shuai

    2016-01-01

    Secretory immunoglobulin A (SIgA) and immunoglobulin G (IgG) antibody-secreting cells (ASCs) are two important cell types in the mucosal immune system. This study aimed to explore the distribution of these ASC populations in the small intestine of Bactrian camels of different ages. Twenty-four Alashan Bactrian camels were divided into the following four age groups: young (1–2 years), pubertal (3–5 years), middle-aged (6–16 years) and old (17–20 years). SIgA and IgG ASCs in the intestinal mucosa lamina propria (LP) were observed and analyzed using immunohistochemcal techniques. The results from all age groups show that both SIgA and IgG ASCs were diffusely distributed in the intestinal LP, and some cells aggregated around the crypts. Moreover, the densities of the two ASC populations gradually increased from the duodenum to the jejunum and then decreased in the ileum. Meanwhile, there were more SIgA ASCs than IgG ASCs in the duodenum, jejunum, and ileum, and these differences were significant in the young and pubertal groups (P<0.05). In addition, the SIgA and IgG ASC densities increased from the young to the pubertal period, peaked at puberty, and then gradually decreased with age. The results demonstrate that the SIgA and IgG ASC distributions help to form two immunoglobulin barriers in the intestinal mucosa to provide full protection, helping to maintain homeostasis. These findings also underscore the importance of researching the development and degeneration of intestinal mucosal immunity in Bactrian camels. PMID:27249417

  12. Modelling of the Electric Field Distribution in Deep Transcranial Magnetic Stimulation in the Adolescence, in the Adulthood, and in the Old Age.

    PubMed

    Fiocchi, Serena; Longhi, Michela; Ravazzani, Paolo; Roth, Yiftach; Zangen, Abraham; Parazzini, Marta

    2016-01-01

    In the last few years, deep transcranial magnetic stimulation (dTMS) has been used for the treatment of depressive disorders, which affect a broad category of people, from adolescents to aging people. To facilitate its clinical application, particular shapes of coils, including the so-called Hesed coils, were designed. Given their increasing demand and the lack of studies which accurately characterize their use, this paper aims to provide a picture of the distribution of the induced electric field in four realistic human models of different ages and gender. In detail, the electric field distributions were calculated by using numerical techniques in the brain structures potentially involved in the progression of the disease and were quantified in terms of both amplitude levels and focusing power of the distribution. The results highlight how the chosen Hesed coil (H7 coil) is able to induce the maxima levels of E mainly in the prefrontal cortex, particularly for the younger model. Moreover, growing levels of induced electric fields with age were found by going in deep in the brain, as well as a major capability to penetrate in the deepest brain structures with an electric field higher than 50%, 70%, and 90% of the peak found in the cortex. PMID:27069502

  13. Modelling of the Electric Field Distribution in Deep Transcranial Magnetic Stimulation in the Adolescence, in the Adulthood, and in the Old Age

    PubMed Central

    Fiocchi, Serena; Longhi, Michela; Ravazzani, Paolo; Roth, Yiftach; Zangen, Abraham; Parazzini, Marta

    2016-01-01

    In the last few years, deep transcranial magnetic stimulation (dTMS) has been used for the treatment of depressive disorders, which affect a broad category of people, from adolescents to aging people. To facilitate its clinical application, particular shapes of coils, including the so-called Hesed coils, were designed. Given their increasing demand and the lack of studies which accurately characterize their use, this paper aims to provide a picture of the distribution of the induced electric field in four realistic human models of different ages and gender. In detail, the electric field distributions were calculated by using numerical techniques in the brain structures potentially involved in the progression of the disease and were quantified in terms of both amplitude levels and focusing power of the distribution. The results highlight how the chosen Hesed coil (H7 coil) is able to induce the maxima levels of E mainly in the prefrontal cortex, particularly for the younger model. Moreover, growing levels of induced electric fields with age were found by going in deep in the brain, as well as a major capability to penetrate in the deepest brain structures with an electric field higher than 50%, 70%, and 90% of the peak found in the cortex. PMID:27069502

  14. Residence times and age distributions of spring waters at the Semmering catchment area, Eastern Austria, as inferred from tritium, CFCs and stable isotopes.

    PubMed

    Han, Liangfeng; Hacker, Peter; Gröning, Manfred

    2007-03-01

    The groundwater system in the mountainous area of Semmering, Austria, was studied by environmental tracers in several karst springs. The tracers used included stable isotopes ((18)O, (2)H), tritium ((3)H) and chlorofluorocarbons (CFCs). The tracers provided valuable information in regard to (1) the mean altitude of the spring catchment areas; (2) the residence time and age distribution of the spring waters; and (3) the interconnection of the springs to a sinkhole. The combination of the stable isotopic data and the topography/geology provided the estimates of the mean altitudes of the catchment areas. Based on the stable isotopic data the recharge temperature of the spring waters was estimated. The smoothing of precipitation's isotopic signal in spring discharge provided information on the minimum transit time of the spring waters. Due to short observation time, (3)H data alone cannot be used for describing the mean residence time of the karst waters. CFCs, though useful in recognizing the co-existence of young (post-1993) water with old (CFC-free) water, could not be used to resolve age distribution models. It is shown in this article, however, that the combined use of tritium and CFCs can provide a better assessment of models to account for different groundwater age distributions. In Appendix A, a simplified method for collecting groundwater samples for the analysis of CFCs is described. The method provides a real facilitation for fieldwork. Test data are given for this sampling method in regard to potential contamination by atmospheric CFCs.

  15. EFFECTS OF ESTROGEN AND AGING ON THE SYNAPTIC DISTRIBUTION OF PHOSPHORYLATED AKT-IMMUNOREACTIVITY IN THE CA1 REGION OF THE FEMALE RAT HIPPOCAMPUS

    PubMed Central

    Yildirim, Murat; Janssen, William G.M.; Lou, W.Y. Wendy; Akama, Keith T.; McEwen, Bruce S.; Milner, Teresa A.; Morrison, John H.

    2013-01-01

    The estrogen 17β-estradiol (E) increases the axospinous synaptic density and plasticity in the hippocampal CA1 region of young female rats but fails to do so in aged female rats. This E stimulus on synaptic plasticity is associated with the phosphorylation-dependent activation of Akt kinase. Our previous findings demonstrated that increased estrogen levels subsequently increase phosphorylated Akt (pAkt)-immunoreactivity (-IR) within the dendritic shafts and spines of pyramidal neurons in young female rats. Therefore, because Akt can promote cell survival and growth, we tested the hypothesis that the less plastic synapses of aged female rats would contain less E-stimulated pAkt-IR. Here, young (3-4 months) and aged (22-23 months) female rats were ovariectomized seven days prior to a 48-hour administration of either vehicle or E. The pAkt-IR synaptic distribution was then analyzed using post-embedding electron microscopy. In both young and aged rats, pAkt-IR was found in dendritic spines and terminals, and pAkt-IR was particularly abundant at the post-synaptic density. Quantitative analyses revealed that the percentage of pAkt-labeled synapses was significantly greater in young rats compared to aged rats. Nonetheless, E treatment significantly increased pAkt-IR in pre- and post-synaptic profiles of both young and aged rats, although the stimulus in young rats was notably more widespread. These data support the evidence that hormone-activated signaling associated with cell growth and survival is diminished in the aged brain. However, the observation that E can still increase pAkt-IR in aged synapses presents this signaling component as a candidate target for hormone replacement therapies. PMID:20709039

  16. Statistical self-similarity of hotspot seamount volumes modeled as self-similar criticality

    USGS Publications Warehouse

    Tebbens, S.F.; Burroughs, S.M.; Barton, C.C.; Naar, D.F.

    2001-01-01

    The processes responsible for hotspot seamount formation are complex, yet the cumulative frequency-volume distribution of hotspot seamounts in the Easter Island/Salas y Gomez Chain (ESC) is found to be well-described by an upper-truncated power law. We develop a model for hotspot seamount formation where uniform energy input produces events initiated on a self-similar distribution of critical cells. We call this model Self-Similar Criticality (SSC). By allowing the spatial distribution of magma migration to be self-similar, the SSC model recreates the observed ESC seamount volume distribution. The SSC model may have broad applicability to other natural systems.

  17. Using the overdispersed exponential family to estimate the distribution of usual daily intakes of people aged between 18 and 28 in Taiwan.

    PubMed

    Chang, H Y; Suchindran, C M; Pan, W H

    2001-08-15

    Assessment of usual dietary intake of a population is essential to understand the nutrition status of the population. Methods like 24-hour dietary recall and food records are commonly used for this task. However, within-individual variation exists in the food record data. Methods considering measurement errors have been used to evaluate the association between nutrient intakes and diseases. Few have been devoted to estimating the distribution of usual daily intakes. This paper proposes applying the formulation of the overdispersed exponential family to estimate the distribution of usual nutrient intake and applies the adjustments developed by Liu to reduce the variance of the distribution. The proposed method has the advantages of working on the original scale of data and implementation convenience. The adjustment of the variance is carried out by dividing the variance into within-individual variance and among-individual variance. The adjusted variance, then, is used to estimate the distribution of the usual daily intake. Sampling weights are considered in all the steps, except the estimation of the ratio of within to among variance. The data for this study are from the Nutritional and Health Survey in Taiwan conducted between 1993 and 1996 (NAHSIT, 1993-1996). An independent external set of data for people aged between 18 and 28 years (49 males and 20 females) is used to estimate the ratio of within to among individual variance. Due to the availability of data in estimating the ratio of within to among individual variance, 430 males and 422 females in the NAHSIT sample are used to estimate the distribution of usual daily intakes for people aged between 18 and 28 in Taiwan. The distribution also allows us to estimate the proportion of people who do not meet the recommended daily nutrient allowance (RDNA). The results show that the intakes of calcium and vitamin E of this group of people fall far below RDNA. PMID:11468767

  18. Protein repair L-isoaspartyl methyltransferase in plants. Phylogenetic distribution and the accumulation of substrate proteins in aged barley seeds.

    PubMed Central

    Mudgett, M B; Lowenson, J D; Clarke, S

    1997-01-01

    Protein L-isoaspartate (D-aspartate) O-methyltransferases (MTs; EC 2.1.1.77) can initiate the conversion of detrimental L-isoaspartyl residues in spontaneously damaged proteins to normal L-aspartyl residues. We detected this enzyme in 45 species from 23 families representing most of the divisions of the plant kingdom. MT activity is often localized in seeds, suggesting that it has a role in their maturation, quiescence, and germination. The relationship among MT activity, the accumulation of abnormal protein L-isoaspartyl residues, and seed viability was explored in barley (Hordeum vulgare cultivar Himalaya) seeds, which contain high levels of MT. Natural aging of barley seeds for 17 years resulted in a significant reduction in MT activity and in seed viability, coupled with increased levels of "unrepaired" L-isoaspartyl residues. In seeds heated to accelerate aging, we found no reduction of MT activity, but we did observe decreased seed viability and the accumulation of isoaspartyl residues. Among populations of accelerated aged seed, those possessing the highest levels of L-isoaspartyl-containing proteins had the lowest germination percentages. These results suggest that the MT present in seeds cannot efficiently repair all spontaneously damaged proteins containing altered aspartyl residues, and their accumulation during aging may contribute to the loss of seed viability. PMID:9414558

  19. Age-Related Shifts in the Density and Distribution of Genetic Marker Water Quality Indicators in Cow and Calf Feces

    EPA Science Inventory

    Recent studies have shown that different adult bovine animal feeding practices dramatically influence fecal indicator bacteria shedding, however very little is known about juvenile milk-fed calves. Calves (≤ 6 months of age) make up about 16% of the current bovine population in ...

  20. Size and age distributions of Juvenile Connecticut River American shad above Hadley Falls: Influence on outmigration representation and timing

    USGS Publications Warehouse

    O'Donnell, M. J.; Letcher, B.H.

    2008-01-01

    Age- and size-based habitat use and movement patterns of young-of-year American shad in rivers are not well understood. Adult females reach their natal rivers at different times and ascend the river at different rates, which may lead to variation of hatch dates at a single location. Also, shad are serial spawners, so eggs of the same female may be released at different distances from the river mouth. It has long been hypothesized that juvenile shad emigration is a function of size or age, and not necessarily keyed only to a decrease in water temperature during the fall. We seined three sites in the Connecticut River biweekly to collect pre-migrant shad during river residence (spring to fall). During emigration, samples were also collected weekly at two hydroelectric facilities. Otoliths were removed from ???20% of the fish to obtain age and growth rate information. We found increases in length and age over time until late in the season, after which such increases were mostly insigniftlant. Cohorts collected early in the year as pre-migrants were never sampled as migrants later in the year at the hydroelectric projects. Cohorts collected late in the year as migrants were never collected earlier in the year as pre-migrants. Only during a narrow window of time were fish collected as both pre-migrants and migrants. Fish that were hatched later in the season exhibited higher growth rates than fish that were hatched earlier in the season. Copyright ?? 2008 John Wiley & Sons, Ltd.

  1. Changes in sex and non-sex hormones and distribution of erythrocyte antigens in reproductive age women with tumors of body of uterus in Adjara.

    PubMed

    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. PMID:23676481

  2. Shifts in depth distributions of alewives, rainbow smelt, and age-2 lake trout in southern Lake Ontario following establishment of Dreissenids

    USGS Publications Warehouse

    O'Gorman, Robert; Elrod, Joseph H.; Owens, Randall W.; Schneider, Clifford P.; Eckert, Thomas H.; Lantry, Brian F.

    2000-01-01

    In the mid-1990s, biologists conducting assessments of fish stocks in Lake Ontario reported finding alewives Alosa pseudoharengus, rainbow smelt Osmerus mordax, and juvenile lake trout Salvelinus namaycush at greater depths than in the mid-1980s. To determine if depth distributions shifted coincident with the early 1990s colonization of Lake Ontario by exotic Dreissena mussels, we calculated mean depth of capture for each of the three species during trawl surveys conducted annually during 1978–1997 and examined the means for significant deviations from established patterns. We found that mean capture depth of alewives, rainbow smelt, and age-2 lake trout shifted deeper during the build up of the dreissenid population in Lake Ontario but that timing of the shift varied among seasons and species. Depth shifts occurred first for rainbow smelt and age-2 lake trout in June 1991. In 1992, alewives shifted deeper in June followed by age-2 lake trout in July–August. Finally, in 1993 and 1994, the distribution of lake trout and alewives shifted in April–May. Reasons why the three fishes moved to deeper water are not clear, but changes in distribution were not linked to temperature. Mean temperature of capture after the depth shift was significantly lower than before the depth shift except for alewives in April–May. Movement of alewives, rainbow smelt, and age-2 lake trout to colder, deeper water has the potential to alter growth and reproduction schedules by exposing the fish to different temperature regimes and to alter the food chain, increasing predation on Mysis relicta in deep water and decreasing alewife predation on lake trout fry over nearshore spawning grounds in spring.

  3. Phylogenetically related and ecologically similar carnivores harbour similar parasite assemblages.

    PubMed

    Huang, Shan; Bininda-Emonds, Olaf R P; Stephens, Patrick R; Gittleman, John L; Altizer, Sonia

    2014-05-01

    Most parasites infect multiple hosts, but what factors determine the range of hosts a given parasite can infect? Understanding the broad scale determinants of parasite distributions across host lineages is important for predicting pathogen emergence in new hosts and for estimating pathogen diversity in understudied host species. In this study, we used a new data set on 793 parasite species reported from free-ranging populations of 64 carnivore species to examine the factors that influence parasite sharing between host species. Our results showed that parasites are more commonly shared between phylogenetically related host species pairs. Additionally, host species with higher similarity in biological traits and greater geographic range overlap were also more likely to share parasite species. Of three measures of phylogenetic relatedness considered here, the number divergence events that separated host species pairs most strongly influenced the likelihood of parasite sharing. We also showed that viruses and helminths tend to infect carnivore hosts within more restricted phylogenetic ranges than expected by chance. Overall, our results underscore the importance of host evolutionary history in determining parasite host range, even when simultaneously considering other factors such as host ecology and geographic distribution.

  4. Distribution, facies, ages, and proposed tectonic associations of regionally metamorphosed rocks in Southwestern Alaska and the Alaska Peninsula

    USGS Publications Warehouse

    Dusel-Bacon, Cynthia; Doyle, E.O.; Box, S.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.

  5. Hindcasting of the Gulf of Mexico Circulation and Age and Distribution of the Oil Plume Arising from the Deepwater Horizon Spill

    NASA Astrophysics Data System (ADS)

    He, R.; Zhang, W.; Hyun, K.; Chen, K.; Qian, H.

    2010-12-01

    We used a realistic regional ocean model to investigate the Gulf of Mexico circulation and 3-dimensional distributions of oil released from the BP Deepwater Horizon (DH) well. Circulation hindcast was generated by NCSU SABGOM, a ROMS model of the Gulf of Mexico and South Atlantic Bight. We ran this model for the time period of the oil spill starting on April 20, 2010. Simulated ocean states were gauged against in-situ observations, including ship CTD, glider transects, AXBT profiles, drifter trajectories, and HF surface currents. Along with the circulation prediction, an online Eulerian age tracer simulation was used to model the dispersion and age of oil plume over time, the latter information indicates how long the BP DH sourced constituents at a given location ( lon, lat, depth) and time have been in the ocean. The tracer prediction and its skill assessment against subsurface dissolved oxygen anomaly observations (as the proxy of oil plume) will be presented and discussed.

  6. Frequency distribution and discrimination probability of twelve protein genetic variants in human blood as functions of race, sex, and age.

    PubMed

    Grunbaum, B W; Selvin, S; Pace, N; Black, D M

    1978-07-01

    Fresh blood samples were obtained from 6004 whites, 1025 blacks, 1596 Chicano/Amerindians, and 3053 Asians of California and Hawaii. The samples were typed for ABO and Rh groups and were analyzed electrophoretically for ten genetically determined protein variant systems. The effects of race, age, and sex on phenotypic frequencies within each of the twelve genetic systems were investigated. Large frequency differences were found between races but not between different age and sex subgroups within races. It was also demonstrated that the twelve genetic systems behaved statistically independently. Discrimination probabilities were computed for each of the four ethnic groups. These serve as a measure of the effectiveness of the twelve genetic systems examined in individualizing blood samples. The method is discussed for computing the probability that a randomly chosen individual of a given ethnic group possesses the same blood phenotypes as found in a predetermined sample of blood. The results presented here should prove useful in the investigation of civil and criminal cases involving blood samples.

  7. Three ages of Venus

    NASA Technical Reports Server (NTRS)

    Wood, Charles A.; Coombs, Cassandra R.

    1989-01-01

    A central question for any planet is the age of its surface. Based on comparative planetological arguments, Venus should be as young and active as the Earth (Wood and Francis). The detection of probable impact craters in the Venera radar images provides a tool for estimating the age of the surface of Venus. Assuming somewhat different crater production rates, Bazilevskiy et al. derived an age of 1 + or - 0.5 billion years, and Schaber et al. and Wood and Francis estimated an age of 200 to 400 million years. The known impact craters are not randomly distributed, however, thus some area must be older and others younger than this average age. Ages were derived for major geologic units on Venus using the Soviet catalog of impact craters (Bazilevskiy et al.), and the most accessible geologic unit map (Bazilevskiy). The crater counts are presented for (diameters greater than 20 km), areas, and crater densities for the 7 terrain units and coronae. The procedure for examining the distribution of craters is superior to the purely statistical approaches of Bazilevskiy et al. and Plaut and Arvidson because the bins are larger (average size 16 x 10(6) sq km) and geologically significant. Crater densities define three distinct groups: relatively heavily cratered (Lakshmi, mountain belts), moderately cratered (smooth and rolling plains, ridge belts, and tesserae), and essentially uncratered (coronae and domed uplands). Following Schaber et al., Grieve's terrestrial cratering rate of 5.4 + or - 2.7 craters greater than 20 km/10(9) yrs/10(6) sq km was used to calculate ages for the geologic units on Venus. To improve statistics, the data was aggregated into the three crater density groups, deriving the ages. For convenience, the three similar age groups are given informal time stratigraphic unit names, from youngest to oldest: Ulfrunian, Sednaian, Lakshmian.

  8. Influence of secondary preparative parameters and aging effects on PLGA particle size distribution: a sedimentation field flow fractionation investigation.

    PubMed

    Contado, Catia; Vighi, Eleonora; Dalpiaz, Alessandro; Leo, Eliana

    2013-01-01

    Poly(lactic-co-glycolic acid) particles in the 200-400-nm size range were formulated through nanoprecipitation and solvent evaporation methods. Different concentrations of the polymer and stabilizer (Pluronic® F 68) were tested in order to identify the best conditions for making poly(lactic-co-glycolic acid) particles of suitable size, stable in time, and to be used as carriers for brain-targeting drugs. The particles with the best characteristics for delivery system design were those formulated by nanoprecipitation with an organic/water phase ratio of 2:30, a polymer concentration of 25 mg/mL, and a surfactant concentration of 0.83 mg/mL; their surface charge was reasonably negative (approximately -27 mV) and the average size of the almost monodisperse population was roughly 250 nm. Particle characterization was obtained through ζ-potential measurements, scanning electron microscope observations, and particle size distribution determinations; the latter achieved by both photon-correlation spectroscopy and sedimentation field flow fractionation. Sedimentation field flow fractionation, which is considered more reliable than photon-correlation spectroscopy in describing the possible particle size distribution modifications, was used to investigate the effects of 3 months of storage at 4 °C had on the lyophilized particles. Figure Particle size ditribution from the SdFFF and the PCS techniques.

  9. Regional Differences in Carbon Storage Based on Distribution of Forest Age across Russia Using the FAREAST Gap Model and Detailed Forest Inventory Data

    NASA Astrophysics Data System (ADS)

    Shuman, J. K.; Krankina, O. N.; Shugart, H. H.

    2007-12-01

    The FAREAST model, an individual-based forest-dynamics model, was developed to simulate forests of Changbai Mountain in northern China. It was then applied to forests at selected sites in Siberia and the Russian Far East. More recently, the model was used to generate results for expected biomass and species composition of mature forest landscapes for 223 sites across all of Russia. After these results were published, we became aware of actual forest survey data (developed by one of the authors, Krankina) arranged in 10-year intervals based on the age of the forest. Age in this case refers the age of the dominant tree cohort in a stand. These data were in percent coverage of total forest area surveyed for 36 forest sites aggregated in three regions denoted the northwest, south, and far eastern regions of Russia. This presented the opportunity to predict an expected biomass for the three regions corrected for age structure. The original simulation data was sorted to match the field data for regional forest age-cohort structure of the three regions. Thirty-four simulation sites from the original paper were distributed in the three regions used in the field study. This simulation data was re-compiled as biomass (tCha-1) for simulation plots summed at each 10 year interval from year zero to mature forests (250 years) and multiplied times the relative percent coverage in each age category. Using the expected biomass for the three regions derived from the inventory data, we obtain a picture of the current carbon storage across Russia. The potential change in carbon storage for these regions was found by calculating the difference between the expected biomass of a mature forest (250 years), the current forest state (derived from inventory data), and a managed forest condition characterized by an even distribution of age cohorts for each 10-year interval. The simulation biomass data was validated using novel cohort data arranged according to species biomass (tCha-1) from

  10. Variation in carbon storage and its distribution by stand age and forest type in boreal and temperate forests in northeastern China.

    PubMed

    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 <5%, in boreal and temperate forests respectively, and thus play a minor role in total forest C storage in NE China.

  11. The implications of small stem cell niche sizes and the distribution of fitness effects of new mutations in aging and tumorigenesis.

    PubMed

    Cannataro, Vincent L; McKinley, Scott A; St Mary, Colette M

    2016-04-01

    Somatic tissue evolves over a vertebrate's lifetime due to the accumulation of mutations in stem cell populations. Mutations may alter cellular fitness and contribute to tumorigenesis or aging. The distribution of mutational effects within somatic cells is not known. Given the unique regulatory regime of somatic cell division, we hypothesize that mutational effects in somatic tissue fall into a different framework than whole organisms; one in which there are more mutations of large effect. Through simulation analysis, we investigate the fit of tumor incidence curves generated using exponential and power-law distributions of fitness effects (DFE) to known tumorigenesis incidence. Modeling considerations include the architecture of stem cell populations, that is, a large number of very small populations, and mutations that do and do not fix neutrally in the stem cell niche. We find that the typically quantified DFE in whole organisms is sufficient to explain tumorigenesis incidence. Further, deleterious mutations are predicted to accumulate via genetic drift, resulting in reduced tissue maintenance. Thus, despite there being a large number of stem cells throughout the intestine, its compartmental architecture leads to the accumulation of deleterious mutations and significant aging, making the intestinal stem cell niche a prime example of Muller's Ratchet.

  12. Distribution and inferred age of exfoliation joints in the Aar Granite of the central Swiss Alps and relationship to Quaternary landscape evolution

    NASA Astrophysics Data System (ADS)

    Ziegler, Martin; Loew, Simon; Moore, Jeffrey R.

    2013-11-01

    Exfoliation joints are well-known natural fractures limited to near the ground surface. Relatively few details, however, are known about their distribution and age in the Swiss Alps. Exfoliation joints follow the landscape surface at the time of their formation; the age of the associated landscape feature then provides a maximum age of exfoliation joints. While landscape forms can change through time, exfoliation joints preserve elements of former landscape morphologies by their undisturbed orientations. The Grimsel region of the Central Alps is well-suited for analyzing the impact of erosional episodes, and accompanying stress changes, on exfoliation joint formation in granitic rocks. Mapping above and below ground revealed that exfoliation joints are widespread and occur between valley bottoms and mountain crests within glacial (inner and hanging U-shaped trough valleys, glacial cirques, and steep mountain crests) and predominantly fluvial landforms (gently inclined linear slopes above the inner trough valleys, narrow inner-valley gorges, and steep V-shaped side gullies). Based primarily on their geometric properties at the ground surface, three exfoliation joint types were distinguished in our study area: (1) closely spaced (< 1 m) joints oriented distinctly parallel to the present-day ground surface, (2) intermediately spaced (0.6-2 m) joints that are nearly parallel (< 10° difference) to today's mean ground surface at a 10-m scale, and (3) widely spaced (≫ 2 m) joints not parallel to the ground surface. Relating the mapped distribution of exfoliation joint types to identified erosional episodes and landscape features of known and inferred ages, respectively, enables us to distinguish four exfoliation joint generations in the Grimsel area, which most likely formed during the lower Pleistocene (~ 1.5-1 Ma), middle Pleistocene (~ 0.7-0.4 Ma), upper Pleistocene (0.1-0.02 Ma), and Late Glacial/Holocene (< 0.02 Ma). We demonstrate that the most prominent and

  13. Impact of the aging process of black carbon aerosols on their spatial distribution, hygroscopicity, and radiative forcing in a global climate model

    NASA Astrophysics Data System (ADS)

    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

  14. Molecular distributions and stable carbon isotopic compositions of dicarboxylic acids and related compounds in aerosols from Sapporo, Japan: Implications for photochemical aging during long-range atmospheric transport

    NASA Astrophysics Data System (ADS)

    Aggarwal, Shankar G.; Kawamura, Kimitaka

    2008-07-01

    Molecular and stable carbon isotopic (δ13C value) compositions of dicarboxylic acids, ketoacids, and dicarbonyls in aerosol samples (i.e., total suspended particles) collected in Sapporo, northern Japan during spring and summer were determined to better understand the photochemical aging of organic aerosols during long-range transport from East Asia and Siberia. Their molecular distributions were characterized by the predominance of oxalic acid (C2) followed by malonic (C3) or occasionally succinic (C4) acids. Concentrations of total diacids ranged from 106-787 ng m-3 with ketoacids (13-81 ng m-3) and dicarbonyls (2.6-28 ng m-3) being less abundant. Water-soluble organic carbon (WSOC) comprised 23-69% of aerosol organic carbon (OC). OC to elemental carbon (EC) ratios were high (3.6-19, mean: 8.7). The ratios of C3/C4 and WSOC/OC did not show significant diurnal changes, suggesting that the Sapporo aerosols were not seriously affected by local photochemical processes and instead they were already aged. δ13C values of the dominant diacids (C2 - C4) ranged from -14.0 to -25.3‰. Largest δ13C values (-14.0 to -22.4‰, mean: -18.8‰) were obtained for C2, whereas smallest values (-25.1 to -31.4‰, mean: -28.1‰) were for azelaic acid (C9). In general, δ13C values of C2 - C4 diacids became less negative with aerosol aging (i.e., WSOC/OC), presumably due to isotopic fractionation during photochemical degradation of diacids. By comparing the δ13C values of diacids in the Sapporo aerosols with different air mass source regions, we suggest that although initial δ13C values of diacids depend on their precursor sources, the enrichment in 13C can be ascribed to aerosol photochemical aging.

  15. Age, distribution, and significance within a sediment budget, of in-channel depositional surfaces in the Normanby River, Queensland, Australia

    NASA Astrophysics Data System (ADS)

    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 (< ~ 63 μm) of alluvial deposits that sit above the sand and gravel bars of the channel floor, but below the expansive flat surface generally referred to as the floodplain. Variously described as benches, bank 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

  16. Soil-Transmitted Helminths in Pre-School-Aged and School-Aged Children in an Urban Slum: A Cross-Sectional Study of Prevalence, Distribution, and Associated Exposures

    PubMed Central

    Davis, Stephanie M.; Worrell, Caitlin M.; Wiegand, Ryan E.; Odero, Kennedy O.; Suchdev, Parminder S.; Ruth, Laird J.; Lopez, Gerard; Cosmas, Leonard; Neatherlin, John; Njenga, Sammy M.; Montgomery, Joel M.; Fox, LeAnne M.

    2014-01-01

    Soil-transmitted helminths (STHs) are controlled by regular mass drug administration. Current practice targets school-age children (SAC) preferentially over pre-school age children (PSAC) and treats large areas as having uniform prevalence. We assessed infection prevalence in SAC and PSAC and spatial infection heterogeneity, using a cross-sectional study in two slum villages in Kibera, Nairobi. Nairobi has low reported STH prevalence. The SAC and PSAC were randomly selected from the International Emerging Infections Program's surveillance platform. Data included residence location and three stools tested by Kato-Katz for STHs. Prevalences among 692 analyzable children were any STH: PSAC 40.5%, SAC 40.7%; Ascaris: PSAC 24.1%, SAC 22.7%; Trichuris: PSAC 24.0%, SAC 28.8%; hookworm < 0.1%. The STH infection prevalence ranged from 22% to 71% between sub-village sectors. The PSAC have similar STH prevalences to SAC and should receive deworming. Small areas can contain heterogeneous prevalences; determinants of STH infection should be characterized and slums should be assessed separately in STH mapping. PMID:25157123

  17. Soil-transmitted helminths in pre-school-aged and school-aged children in an urban slum: a cross-sectional study of prevalence, distribution, and associated exposures.

    PubMed

    Davis, Stephanie M; Worrell, Caitlin M; Wiegand, Ryan E; Odero, Kennedy O; Suchdev, Parminder S; Ruth, Laird J; Lopez, Gerard; Cosmas, Leonard; Neatherlin, John; Njenga, Sammy M; Montgomery, Joel M; Fox, LeAnne M

    2014-11-01

    Soil-transmitted helminths (STHs) are controlled by regular mass drug administration. Current practice targets school-age children (SAC) preferentially over pre-school age children (PSAC) and treats large areas as having uniform prevalence. We assessed infection prevalence in SAC and PSAC and spatial infection heterogeneity, using a cross-sectional study in two slum villages in Kibera, Nairobi. Nairobi has low reported STH prevalence. The SAC and PSAC were randomly selected from the International Emerging Infections Program's surveillance platform. Data included residence location and three stools tested by Kato-Katz for STHs. Prevalences among 692 analyzable children were any STH: PSAC 40.5%, SAC 40.7%; Ascaris: PSAC 24.1%, SAC 22.7%; Trichuris: PSAC 24.0%, SAC 28.8%; hookworm < 0.1%. The STH infection prevalence ranged from 22% to 71% between sub-village sectors. The PSAC have similar STH prevalences to SAC and should receive deworming. Small areas can contain heterogeneous prevalences; determinants of STH infection should be characterized and slums should be assessed separately in STH mapping.

  18. Self-similar parabolic plasmonic beams.

    PubMed

    Davoyan, Arthur R; Turitsyn, Sergei K; Kivshar, Yuri S

    2013-02-15

    We demonstrate that an interplay between diffraction and defocusing nonlinearity can support stable self-similar plasmonic waves with a parabolic profile. Simplicity of a parabolic shape combined with the corresponding parabolic spatial phase distribution creates opportunities for controllable manipulation of plasmons through a combined action of diffraction and nonlinearity.

  19. Magnesium and healthy aging.

    PubMed

    Veronese, Nicola; Zanforlini, Bruno Micael; Manzato, Enzo; Sergi, Giuseppe

    2015-01-01

    Magnesium (Mg) is relatively stable in the intracellular compartment, although decreases linearly with advancing age. This begs the question as to whether Mg could be used as biomarker of aging. A biomarker of aging is a biological parameter of an organism that, in the absence of disease, better predicts functional capability at a later age than the chronological age. Bone and muscle Mg content might be useful biomarkers, but the need for biopsies and the heterogeneous distribution of Mg in bones and muscles strongly limit the application of these methods in clinical practice. Similar considerations can be made for urinary Mg assessment, particularly after a loading test. Markers of Mg in blood seem fairly unreliable as biomarkers of aging since they are strongly dependent upon renal function, do not reflect the intracellular Mg status, and, in some investigations, are within normal ranges although other Mg parameters are not. Other investigations (e.g. nuclear magnetic resonance with fluorescent probes) seem to be promising, but their availability remains limited. PMID:26446714

  20. Fatal accident distribution by age, gender and head injury, and death probability at accident scene in Mashhad, Iran, 2006-2009.

    PubMed

    Zangooei Dovom, Hossein; Shafahi, Yousef; Zangooei Dovom, Mehdi

    2013-01-01

    Several studies have investigated road traffic deaths, but few have compared by road user type. Iran, with an estimated 44 road traffic deaths per 100,000 population in 2002 had higher road traffic deaths than any other country for which reliable estimates can be made. So, the present study was conducted on road death data and identified fatal accident distribution by age, gender and head injury as well as the influences of age and gender on deaths at accident scenes for all road user groups. Data used in this study are on fatal road accidents recorded by forensic medicine experts of the Khorasan Razavi province in Mashhad, the capital of the province, the second largest city and the largest place of pilgrimage, immigration and tourism in Iran. Chi-square test and odds ratio were used to identify the relation of death place with age and gender in 2495 fatal road accidents from 2006 to 2009. The t-test and analysis of variance were employed for continues variable, age, to compare males' and females' mean age for all road user categories. For two genders, all three groups of fatalities (pedestrian, motorcyclist and motor vehicle occupant) had a peak at the ages of 21-30. The youngest were male motorcyclists (mean age = 28). Old pedestrians were included in road deaths very much, too. Male/female overall ratio was 3.41 and the highest male/female ratio was related to motorcyclists (14). The overall ratio of head injury to other organ injuries (torso and underbody) was 2.51 and pedestrians had the largest amount of head injury (38.2%). Regarding death at accident scene, for all road users, gender did not have any significant relation with death at the scene (P-value > 0.1); on the contrary, age had significant relation (P-value < 0.05). Females were more vulnerable at accident scenes (male/female ratio at accident sense < 1). Pedestrians aged 21-30, motorcyclists 41-50 and motor vehicle occupants 31-40 died the most at accident scenes. Identifying the most

  1. Aiming for Efficiency by Detecting Structural Similarity

    NASA Astrophysics Data System (ADS)

    Winter, Judith; Jeliazkov, Nikolay; Kühne, Gerold

    When applying XML-Retrieval in a distributed setting, efficiency issues have to be considered, e.g. reducing the network traffic involved in an swering a given query. The new Efficiency Track of INEX gave us the opportu nity to explore the possibility of improving both effectiveness and efficiency by exploiting structural similarity. We ran some of the track’s highly structured queries on our top-k search engine to analyze the impact of various structural similarity functions. We applied those functions first to the ranking and based on that to the query routing process. Our results indicate that detection of structural similarity can be used in order to re duce the amount of messages sent between distributed nodes and thus lead to more efficiency of the search.

  2. Middle Stone Age (MSA) site distributions in eastern Africa and their relationship to Quaternary environmental change, refugia and the evolution of Homo sapiens

    NASA Astrophysics Data System (ADS)

    Basell, Laura S.

    2008-12-01

    This paper considers the evolution of Homo sapiens in eastern Africa in relation to refugia and bottlenecks around ˜200 ka BP, at a macro scale. Middle Stone Age (MSA) lithics, site distributions and locations are analysed in relation to palaeovegetation maps of the last glacial/interglacial cycle, which are used as a proxy for earlier climate cycles. A "push and pull" model is then postulated for the spread of Homo sapiens out of refugia in eastern Africa, involving both volcanism (push) and habitat availability (pull). A date within OIS 5 is suggested for this expansion to other parts of the continent, and potentially further afield, contrary to a frequently proposed expansion within OIS 3.

  3. Geographic distribution, age pattern and sites of lesions in a cohort of Buruli ulcer patients from the Mapé Basin of Cameroon.

    PubMed

    Bratschi, Martin W; Bolz, Miriam; Minyem, Jacques C; Grize, Leticia; Wantong, Fidèle G; Kerber, Sarah; Njih Tabah, Earnest; Ruf, Marie-Thérèse; Mou, Ferdinand; Noumen, Djeunga; Um Boock, Alphonse; Pluschke, Gerd

    2013-01-01

    Buruli ulcer (BU), a neglected tropical disease of the skin, caused by Mycobacterium ulcerans, occurs most frequently in children in West Africa. Risk factors for BU include proximity to slow flowing water, poor wound care and not wearing protective clothing. Man-made alterations of the environment have been suggested to lead to increased BU incidence. M. ulcerans DNA has been detected in the environment, water bugs and recently also in mosquitoes. Despite these findings, the mode of transmission of BU remains poorly understood and both transmission by insects or direct inoculation from contaminated environment have been suggested. Here, we investigated the BU epidemiology in the Mapé basin of Cameroon where the damming of the Mapé River since 1988 is believed to have increased the incidence of BU. Through a house-by-house survey in spring 2010, which also examined the local population for leprosy and yaws, and continued surveillance thereafter, we identified, till June 2012, altogether 88 RT-PCR positive cases of BU. We found that the age adjusted cumulative incidence of BU was highest in young teenagers and in individuals above the age of 50 and that very young children (<5) were underrepresented among cases. BU lesions clustered around the ankles and at the back of the elbows. This pattern neither matches any of the published mosquito biting site patterns, nor the published distribution of small skin injuries in children, where lesions on the knees are much more frequent. The option of multiple modes of transmission should thus be considered. Analyzing the geographic distribution of cases in the Mapé Dam area revealed a closer association with the Mbam River than with the artificial lake. PMID:23785529

  4. A Reactive Transport Model for the Distribution and Age of Carbon in Soils and Sediments Through Direct Simulation of the Stable and Radiogenic Isotopologues

    NASA Astrophysics Data System (ADS)

    Druhan, J. L.; Lawrence, C. R.

    2015-12-01

    We present a reactive transport (RT) approach to link hydrologic transport, geochemical transformations and microbial activity influencing the magnitude and residence time of different carbon pools under variably saturated conditions. This model explicitly simulates the simultaneous transport, transformation, fractionation and decay of the three isotopes of carbon (12C, 13C and 14C) through a mechanistic framework. This is demonstrated with a modification of the CrunchTope multi-component RT software to extend the isotope-specific versions of both microbially-mediated and transition state theory (TST) rate laws to accommodate a three-isotope system. In addition both aqueous and solid phase decay of 14C are tracked, yielding in an implicit means of accounting for the 13C/12C correction in normalized radiocarbon ages. The capacity of this approach to quantify the storage and flux of carbon through subsurface compartments is demonstrated using two examples distinguished by timescale. The first considers a simplified flow path in which an influent containing labile organic carbon is distributed by biogenic reduction and mineralization into a suite of reaction products. The residence time of these pools and their characteristic stable isotope ratios are tracked through a variety of transient processes occurring at short timescales (e.g. months). These include a change in fluid flow rate, a limitation of ammonium supporting anabolic growth and an influx of oxygenated fluid. The second example considers the distribution of carbon over the timescale of soil development (e.g., millennia), using a dataset of stable isotope ratios and radiocarbon ages of organic and inorganic carbon present in both dissolved and solid phases from a soil chronosequence near Santa Cruz, CA. The results of these model simulations suggest the promise of this tool for improving our understanding of coupling between hydrologic transport and biogeochemical reactions in soils.

  5. Geographic Distribution, Age Pattern and Sites of Lesions in a Cohort of Buruli Ulcer Patients from the Mapé Basin of Cameroon

    PubMed Central

    Bratschi, Martin W.; Bolz, Miriam; Minyem, Jacques C.; Grize, Leticia; Wantong, Fidèle G.; Kerber, Sarah; Njih Tabah, Earnest; Ruf, Marie-Thérèse; Mou, Ferdinand; Noumen, Djeunga; Um Boock, Alphonse; Pluschke, Gerd

    2013-01-01

    Buruli ulcer (BU), a neglected tropical disease of the skin, caused by Mycobacterium ulcerans, occurs most frequently in children in West Africa. Risk factors for BU include proximity to slow flowing water, poor wound care and not wearing protective clothing. Man-made alterations of the environment have been suggested to lead to increased BU incidence. M. ulcerans DNA has been detected in the environment, water bugs and recently also in mosquitoes. Despite these findings, the mode of transmission of BU remains poorly understood and both transmission by insects or direct inoculation from contaminated environment have been suggested. Here, we investigated the BU epidemiology in the Mapé basin of Cameroon where the damming of the Mapé River since 1988 is believed to have increased the incidence of BU. Through a house-by-house survey in spring 2010, which also examined the local population for leprosy and yaws, and continued surveillance thereafter, we identified, till June 2012, altogether 88 RT-PCR positive cases of BU. We found that the age adjusted cumulative incidence of BU was highest in young teenagers and in individuals above the age of 50 and that very young children (<5) were underrepresented among cases. BU lesions clustered around the ankles and at the back of the elbows. This pattern neither matches any of the published mosquito biting site patterns, nor the published distribution of small skin injuries in children, where lesions on the knees are much more frequent. The option of multiple modes of transmission should thus be considered. Analyzing the geographic distribution of cases in the Mapé Dam area revealed a closer association with the Mbam River than with the artificial lake. PMID:23785529

  6. Functional Similarity and Interpersonal Attraction.

    ERIC Educational Resources Information Center

    Neimeyer, Greg J.; Neimeyer, Robert A.

    1981-01-01

    Students participated in dyadic disclosure exercises over a five-week period. Results indicated members of high functional similarity dyads evidenced greater attraction to one another than did members of low functional similarity dyads. "Friendship" pairs of male undergraduates displayed greater functional similarity than did "nominal" pairs from…

  7. Transformation and Alignment in Similarity

    ERIC Educational Resources Information Center

    Hodgetts, Carl J.; Hahn, Ulrike; Chater, Nick

    2009-01-01

    This paper contrasts two structural accounts of psychological similarity: structural alignment (SA) and Representational Distortion (RD). SA proposes that similarity is determined by how readily the structures of two objects can be brought into alignment; RD measures similarity by the complexity of the transformation that "distorts" one…

  8. Acoustic Similarity and Dichotic Listening.

    ERIC Educational Resources Information Center

    Benson, Peter

    1978-01-01

    An experiment tests conjectures that right ear advantage (REA) has an auditory origin in competition or interference between acoustically similar stimuli and that feature-sharing effect (FSE) has its origin in assignment of features of phonetically similar stimuli. No effect on the REA for acoustic similarity, and a clear effect of acoustic…

  9. Geomorphology and Geology of the Southwestern Margaritifer Sinus and Argyre Regions of Mars. Part 2: Crater Size-frequency Distribution Curves and Geomorphic Unit Ages

    NASA Technical Reports Server (NTRS)

    Parker, T. J.; Pieri, D. C.

    1985-01-01

    In assessing the relative ages of the geomorphic/geologic units, crater counts of the entire unit or nearly the entire unit were made and summed in order to get a more accurate value than obtainable by counts of isolated sections of each unit. Cumulative size-frequency counts show some interesting relationships. Most of the units show two distinct crater populations with a flattening out of the distribution curve at and below 10 km diameter craters. Above this crater size the curves for the different units diverge most notably. In general, the variance may reflect the relative ages of these units. At times, however, in the larger crater size range, these curves can overlap and cross on another. Also the error bars at these larger sizes are broader (and thus more suspect), since counts of larger craters show more scatter, whereas the unit areas remain constant. Occasional clusters of relatively large craters within a given unit, particularly one of limited areal extent, can affect the curve so that the unit might seem to be older than units which it overlies or cuts.

  10. Effects of age and reproductive experience on the distribution of prolactin and growth hormone secreting cells in the anterior pituitary of a passerine.

    PubMed

    Christensen, Debora; Vleck, Carol M

    2015-10-01

    Plasma prolactin (PRL) is released from lactotrophs in the anterior pituitary. As plasma PRL levels rise during incubation in domestic fowl, the number of lactotrophs (PRL-immunoreactive, PRL-IR cells) increases while the number of growth hormone secreting cells, somatotrophs (GH-IR cells), declines. We measured plasma PRL levels using radioimmunoassay (RIA) and examined the distribution of lactotrophs and somatotrophs in the anterior pituitary of breeding and nonbreeding zebra finches of known ages with and without prior breeding experience using fluorescent immunohistochemistry (IHC). Plasma PRL levels were higher in breeding than in nonbreeding birds, regardless of age, sex, or previous breeding history. PRL-IR cells were localized primarily, but not exclusively, to the cephalic aspect of the anterior pituitary (AP) and along the ventral margin. Birds with prior reproductive experience had more PRL-IR cells than birds with no prior reproductive experience and breeders had slightly higher PRL-IR cell counts than did nonbreeders, but there was no correlation between the number of PRL-IR cells and plasma PRL levels. GH-IR cells were concentrated in the caudal aspect of the AP with some cells in the cephalic lobe, but numbers did not differ between any of the groups studied. An increase in PRL-IR cells corresponded with an increase in GH-IR cells. An increase in lactotroph number with reproductive experience in zebra finches may facilitate future reproductive events by allowing for more robust PRL secretion and increased reproductive success.

  11. Application Of A Dynamic Model to Assess Geomorphic and Hydrologic Controls on Age-0 Colorado Pikeminnow Distribution in the Green River, Colorado And Utah

    NASA Astrophysics Data System (ADS)

    Schmidt, J. C.

    2005-05-01

    Analysis of field data and development and application of a dynamic model indicate that water releases from Flaming Gorge Dam have a large potential effect on larval drift and distribution of age-0 Colorado pikeminnow (Ptychocheilus lucius) in the middle Green River. The model predicts that high releases at the time of drift greatly increase the proportion of the population transported beyond the study area to unfavorable river environments. The model also predicts that channel simplification caused by flow regulation results in a more even longitudinal distribution of larval fish habitat. Colorado pikeminnow are a federally endangered species endemic to the Colorado River basin that utilize backwaters during their larval stage. The present agency-mandated field-sampling program for backwater habitats is probably inadequate, because it takes place at a time when the model predicts that most larval fish have drifted beyond the study area. Development of the model shows that the role of the geomorphic and hydraulic attributes that control larval drift and transport into backwaters, and that were parameterized in the model, are not well known.

  12. Similarity Theory of Withdrawn Water Temperature Experiment

    PubMed Central

    2015-01-01

    Selective withdrawal from a thermal stratified reservoir has been widely utilized in managing reservoir water withdrawal. Besides theoretical analysis and numerical simulation, model test was also necessary in studying the temperature of withdrawn water. However, information on the similarity theory of the withdrawn water temperature model remains lacking. Considering flow features of selective withdrawal, the similarity theory of the withdrawn water temperature model was analyzed theoretically based on the modification of governing equations, the Boussinesq approximation, and some simplifications. The similarity conditions between the model and the prototype were suggested. The conversion of withdrawn water temperature between the model and the prototype was proposed. Meanwhile, the fundamental theory of temperature distribution conversion was firstly proposed, which could significantly improve the experiment efficiency when the basic temperature of the model was different from the prototype. Based on the similarity theory, an experiment was performed on the withdrawn water temperature which was verified by numerical method. PMID:26065020

  13. Aging gauge

    DOEpatents

    Betts, Robert E.; Crawford, John F.

    1989-01-01

    An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

  14. Aging gauge

    DOEpatents

    Betts, Robert E.; Crawford, John F.

    1989-04-04

    An aging gauge comprising a container having a fixed or a variable sized t opening with a cap which can be opened to control the sublimation rate of a thermally sublimational material contained within the container. In use, the aging gauge is stored with an item to determine total heat the item is subjected to and also the maximum temperature to which the item has been exposed. The aging gauge container contains a thermally sublimational material such as naphthalene or similar material which has a low sublimation rate over the temperature range from about 70.degree. F. to about 160.degree. F. The aging products determined by analyses of a like item aged along with the aging gauge for which the sublimation amount is determined is employed to establish a calibration curve for future aging evaluation. The aging gauge is provided with a means for determining the maximum temperature exposure (i.e., a thermally indicating material which gives an irreversible color change, Thermocolor pigment). Because of the relationship of doubling reaction rates for increases of 10.degree. C., equivalency of item used in accelerated aging evaluation can be obtained by referring to a calibration curve depicting storage temperature on the abscissa scale and multiplier on the ordinate scale.

  15. Trends and spatial distribution of deaths of children aged 12-60 months in São Paulo, Brazil, 1980-98.

    PubMed Central

    Antunes, José Leopoldo Ferreira; Waldman, Eliseu Alves

    2002-01-01

    OBJECTIVE: To describe trends in the mortality of children aged 12-60 months and to perform spatial data analysis of its distribution at the inner city district level in São Paulo from 1980 to 1998. METHODS: Official mortality data were analysed in relation to the underlying causes of death. The population of children aged 12-60 months, disaggregated by sex and age, was estimated for each year. Educational levels, income, employment status, and other socioeconomic indices were also assessed. Statistical Package for Social Sciences software was used for the statistical processing of time series. The Cochrane-Orcutt procedure of generalized least squares regression analysis was used to estimate the regression parameters with control of first-order autocorrelation. Spatial data analysis employed the discrimination of death rates and socioeconomic indices at the inner city district level. For classifying area-level death rates the method of K-means cluster analysis was used. Spatial correlation between variables was analysed by the simultaneous autoregressive regression method. FINDINGS: There was a steady decline in death rates during the 1980s at an average rate of 3.08% per year, followed by a levelling off. Infectious diseases remained the major cause of mortality, accounting for 43.1% of deaths during the last three years of the study. Injuries accounted for 16.5% of deaths. Mortality rates at the area level clearly demonstrated inequity in the city's health profile: there was an increasing difference between the rich and the underprivileged social strata in this respect. CONCLUSION: The overall mortality rate among children aged 12-60 months dropped by almost 30% during the study period. Most of the decline happened during the 1980s. Many people still live in a state of deprivation in underserved areas. Time-series and spatial data analysis provided indications of potential value in the planning of social policies promoting well-being, through the identification

  16. Distribution of High-Sensitivity C-Reactive Protein and Its Relationship with Other Cardiovascular Risk Factors in the Middle-Aged Chinese Population

    PubMed Central

    Wang, Zengwu; Wang, Xin; Chen, Zuo; Zhang, Linfeng; Zhu, Manlu

    2016-01-01

    Background: An increased concentration of high-sensitivity C-reactive protein (hs-CRP) indicates risk for cardiovascular disease (CVD). Because the available data is limited, a cross-sectional survey was conducted in 2009–2010 to describe hs-CRP distribution and its relationship with established CVD risk factors. Methods: A population-based sample of adults aged 35 to 64 years (n = 14,046) was taken from 12 research populations across China. Demographic and clinical characteristics were recorded, and hs-CRP measured. Pearson’s and Kendall’s tau-b correlation coefficient, and multiple regression analyses were used to test the relationship between hs-CRP and other CVD risk factors. Results: For 8389 (4412 females) eligible participants, hs-CRP was 1.89 ± 4.37 mg/L (median (25th, 75th): 0.80 (0.40, 1.80)), and increased with age, BP, glucose, and BMI (p < 0.05), males had significantly higher hs-CRP than females (2.07 (4.89) vs. 1.73 (3.83), p < 0.001). About 24.3% had the hs-CRP concentrations more than the top quartile (25.8% in males, 22.9% in females), 12.3% (13.3% in males, 11.5% in females) >3 mg/L. There was a significant positive correlation of quartiles of hs-CRP concentrations with age, SBP, DBP, glucose level, BMI, LDL-C/HDL-C ratio, and LDL-C/total cholesterol ratio (p < 0.001). The elevated hs-CRP (>1.80 mg/L) related positively with age, LDL-C, BP, glucose, BMI, and living north and negatively with HDL-C/TC, LDL-C/TC, TC independently (p < 0.05). For subjects with coexisting hypertension, diabetes, high cholesterol, and obesity, about 63.0% were in the top quartile of hs-CRP concentrations. Conclusions: Hs-CRP was associated with most of the known CVD risk factors. Measurement of hs-CRP may provide a more comprehensive view of the patient’s overall risk profile in the Chinese population. PMID:27589783

  17. Genome-wide analysis of copy number variations reveals that aging processes influence body fat distribution in Korea Associated Resource (KARE) cohorts.

    PubMed

    Lee, Bo-Young; Shin, Dong Hyun; Cho, Seoae; Seo, Kang-Seok; Kim, Heebal

    2012-11-01

    Many anthropometric measures, including body mass index (BMI), waist-to-hip ratio (WHR), and subcutaneous fat thickness, are used as indicators of nutritional status, fertility and predictors of future health outcomes. While BMI is currently the best available estimate of body adiposity, WHR and skinfold thickness at various sites (biceps, triceps, suprailiac, and subscapular) are used as indices of body fat distribution. Copy number variation (CNV) is an attractive emerging approach to the study of associations with various diseases. In this study, we investigated the dosage effect of genes in the CNV genome widely associated with fat distribution phenotypes in large cohorts. We used the Affymetrix genome-wide human SNP Array 5.0 data of 8,842 healthy unrelated adults in KARE cohorts and identified CNVs associated with BMI and fat distribution-related traits including WHR and subcutaneous skinfold thickness at suprailiac (SUP) and subscapular (SUB) sites. CNV segmentation of each chromosome was performed using Golden Helix SVS 7.0, and single regression analysis was used to identify CNVs associated with each phenotype. We found one CNV for BMI, 287 for WHR, 2,157 for SUP, and 2,102 for SUB at the 5% significance level after Holm-Bonferroni correction. Genes included in the CNV were used for the analysis of functional annotations using the Database for Annotation, Visualization and Integrated Discovery (DAVID v6.7b) tool. Functional gene classification analysis identified five significant gene clusters (metallothionein, ATP-binding proteins, ribosomal proteins, kinesin family members, and zinc finger proteins) for SUP, three (keratin-associated proteins, zinc finger proteins, keratins) for SUB, and one (protamines) for WHR. BMI was excluded from this analysis because the entire structure of no gene was identified in the CNV. Based on the analysis of genes enriched in the clusters, the fat distribution traits of KARE cohorts were related to the fat redistribution

  18. Estimates of injecting drug users at the national and local level in developing and transitional countries, and gender and age distribution

    PubMed Central

    Aceijas, C; Friedman, S R; Cooper, H L F; Wiessing, L; Stimson, G V; Hickman, M

    2006-01-01

    Objective To present and update available national and subnational estimates of injecting drug users (IDUs) in developing/transitional countries, and provide indicative estimates of gender and age distribution. Methods Literature review of both grey and published literature including updates from previously reported estimates on estimates of IDU population and data sources giving age and gender breakdowns. The scope area was developing/transitional countries and the reference period was 1998–2005. Results Estimates of IDU numbers were available in 105 countries and 243 subnational areas. The largest IDU populations were reported from Brazil, China, India, and Russia (0.8 m, 1.9 m, 1.1 m, and 1.6 m respectively). Subnational areas with the largest IDU populations (35 000–79 000) are: Warsaw (Poland); Barnadul, Irtkustk, Nizhny‐Novgorod, Penza, Voronez, St Petersburg, and Volgograd (Russia); New Delhi and Mumbai (India); Jakarta (Indonesia), and Bangkok (Thailand). By region, Eastern Europe and Central Asia have the largest IDU prevalence (median 0.65%) (min 0.3%; max 2.2%; Q1 0.79%; Q3 1.74%) followed by Asia and Pacific: 0.24% (min 0.004%; max 1.47%; Q1 0.37%; Q3 1.1%). In the Middle East and Africa the median value equals 0.2% (min 0.0003%; max 0.35%; Q1 0.09%; Q3 0.26%) and in Latin America and the Caribbean: 0.12% (min 0.002%; max 7.04%; Q1 1.76%; Q3 5.28%). Greater dispersion of national IDU prevalences was observed in Eastern Europe and Central Asia, and Asia and Pacific (IQR 1.91 and 1.47 respectively). Subnational areas with the highest IDU prevalence among adults (8–14.9%) were Shymkent (Kazakhstan), Balti (Moldova), Astrakhan, Barnadul, Irtkustk, Khabarovsk, Kaliningrad, Naberezhnyje Chelny, Penza, Togliatti, Volgograd, Voronez, and Yaroslavl (Russia), Dushanbe (Tajikistan), Ashgabad (Turkmenistan), Ivano‐Frankivsk and Pavlograd (Ukraine) and Imphal, Manipur (India). 66% (297/447) of the IDU estimates were reported without technical

  19. Dynamic similarity in erosional processes

    USGS Publications Warehouse

    Scheidegger, A.E.

    1963-01-01

    A study is made of the dynamic similarity conditions obtaining in a variety of erosional processes. The pertinent equations for each type of process are written in dimensionless form; the similarity conditions can then easily be deduced. The processes treated are: raindrop action, slope evolution and river erosion. ?? 1963 Istituto Geofisico Italiano.

  20. Discuss Similarity Using Visual Intuition

    ERIC Educational Resources Information Center

    Cox, Dana C.; Lo, Jane-Jane

    2012-01-01

    The change in size from a smaller shape to a larger similar shape (or vice versa) is created through continuous proportional stretching or shrinking in every direction. Students cannot solve similarity tasks simply by iterating or partitioning a composed unit, strategies typically used on numerical proportional tasks. The transition to thinking…

  1. Relative risk of Alzheimer disease and age-at-onset distributions, based on APOE genotypes among elderly African Americans, Caucasians, and Hispanics in New York City.

    PubMed Central

    Tang, M. X.; Maestre, G.; Tsai, W. Y.; Liu, X. H.; Feng, L.; Chung, W. Y.; Chun, M.; Schofield, P.; Stern, Y.; Tycko, B.; Mayeux, R.

    1996-01-01

    Apolipoprotein-E epsilon 4 (APOE-epsilon 4) has been consistently associated with Alzheimer disease (AD) and may be responsible for an earlier age at onset. We have previously reported a diminished association between APOE-epsilon 4 and AD in African Americans. Using a new method, which allows inclusion of censored information, we compared relative risks by APOE genotypes in an expanded collection of cases and controls from three ethnic groups in a New York community. The relative risk for AD associated with APOE-epsilon 4 homozygosity was increased in all ethnic groups (African American relative risk [RR]=3.0; 95% confidence interval [CI]=1.5-5.9; Caucasian RR=7.3, 95% CI=2.5-21.6; and Hispanic RR=2.5, 95% CI=1.1-5.7), compared with those with APOE-epsilon 3/epsilon 3 genotypes. The risk was also increased for APOE-epsilon 4 heterozygous Caucasians (RR=2.9, 95% CI=1.7-5.1) and Hispanics (RR=1.6, 95% CI=1.1-2.3), but not for African Americans (RR=0.6, 95% Ci=0.4-0.9). The age distribution of the proportion of Caucasians and Hispanics without AD was consistently lower for APOE-epsilon 4 homozygous and APOE-epsilon 4 heterozygous individuals than for those with other APOE genotypes. In African Americans this relationship was observed only in APOE-epsilon 4 homozygotes. These results confirm that APOE genotypes influence the RR of AD in Caucasians and Hispanics. Differences in risk among APOE-epsilon 4 heterozygote African Americans suggest that other genetic or environmental factors may modify the effect of APOE-epsilon 4 in some populations. PMID:8644717

  2. (U-Th-Sm)/He thermochronological age distribution in a slowly cooled plutonic complex (Ploumanac'h intrusion, France): insights into helium diffusion processes.

    NASA Astrophysics Data System (ADS)

    Recanati, A. C.; Gautheron, C.; Barbarand, J.; Tassan-Got, L.; Missenard, Y.; Pinna-Jamme, R.

    2015-12-01

    (U-Th-Sm)/He thermochronology is widely used to determine the thermal histories of mountain ranges and sedimentary basins. Apatite crystals retain helium at low temperatures, thus giving an insight into upper crustal evolution (e.g. exhumation, subsidence, erosion). Advanced models predict He production and diffusion rates in apatite crystals, thereby allowing determination of helium dates by integration over time/temperature paths (e.g. Gautheron et al., 2009). However, scattered dates and discordance between predicted and measured dates suggest that other parameters than time or temperature may also influence helium contents in apatite. The present study determines the variables that affect He diffusion in apatite over long timescales. We report the (U-Th-Sm)/He date distribution within a slowly cooled intrusion, along with AFT data, as well as extensive petrological and chemical characterization. The Ploumanac'h site (Brittany, France) was chosen because it includes small-scale spatial variations in petrology and chemistry (ages range from 120 to 160 ±10 Myrs. The old and scattered (U-Th-Sm)/He ages cannot be explained with current models. We investigate the influence of monograin chemistry, crystal defect, and sample petrology on (U-Th-Sm)/He dates. Data confirm that He can be stored at defect sites, but also support a decrease in He retentivity for high equivalent damage fraction (>6-9106 tracks/cm2). GAUTHERON C., TASSAN-GOT L., BARBARAND J., PAGEL M., 2009. Effect of alpha-damage annealing on apatite (U-Th)/He thermochronology. Chem. Geol. 266, 166-179.

  3. Relative risk of Alzheimer disease and age-at-onset distributions, based on APOE genotypes among elderly African Americans, caucasians, and hispanics in New York City

    SciTech Connect

    Tang, M.X.; Liu, X.H.; Stern, Y.

    1996-03-01

    Apolipoprotein-E {epsilon}4 (APOE-{epsilon}4) has been consistently associated with Alzheimer disease (AD) and may be responsible for an earlier age at onset. We have previously reported a diminished association between APOE-{epsilon}4 and AD in African Americans. Using a new method, which allows inclusion of censored information, we compared relative risks by APOE genotypes in an expanded collection of cases and controls from three ethnic groups in a New York community. The relative risk for AD associated with APOE-{epsilon}4 homozygosity was increased in all ethnic groups (African American relative risk [RR] = 3.0; 95% confidence interval [CI] = 1.5-5.9; Caucasian RR = 7.3, 95% CI = 2.5-21.6; and Hispanic RR = 2.5, 95% CI = 1.1-5.7), compared with those with APOE-{epsilon}3/{epsilon}3 genotypes. The risk was also increased for APOE-{epsilon}4 heterozygous Caucasians (RR = 2.9, 95% CI = 1.7-5.1) and Hispanics (RR = 1.6,95% CI = 1.1-2.3), but not for African Americans (RR = 0.6, 95% CI = 0.4-0.9). The age distribution of the proportion of Caucasians and Hispanics without AD was consistently lower for APOE-{epsilon}4 homozygous and APOE-{epsilon}4 heterozygous individuals than for those with other APOE genotypes. In African Americans this relationship was observed only in APOE-{epsilon}4 homozygotes. These results confirm that APOE genotypes influence the RR of AD in Caucasians and Hispanics. Differences in risk among APOE-{epsilon}4 heterozygote African Americans suggest that other genetic or environmental factors may modify the effect of APOE-{epsilon}4 in some populations. 58 refs., 3 figs., 4 tabs.

  4. Influence of alternating soil drying and wetting on the desorption and distribution of aged 14C-labeled pesticide residues in soil organic fractions

    NASA Astrophysics Data System (ADS)

    Jablonowski, N. D.; Mucha, M.; Thiele, B.; Hofmann, D.; Burauel, P.

    2012-04-01

    A laboratory experiment was conducted to evaluate the effect of alternating soil drying and wetting on the release of aged 14C-labeled pesticide residues and their distribution in soil organic fractions (humic acids, fulvic acids, and humin substances). The used soils (gleyic cambisol; Corg 1.2%, pH 7.2) were obtained from the upper soil layer of two individual outdoor lysimeter studies containing either environmentally long-term aged 14C residues of the herbicide ethidimuron (ETD; 0-10 cm depth; time of aging: 9 years) or methabenzthiazuron (MBT; 0-30 cm depth; time of aging: 17 years). Triplicate soil samples (10 g dry soil equivalents) were (A=dry/wet) previously dried (45° C) or (B=wet/wet) directly mixed with pure water (1+2, w:w), shaken (150 rpm, 1 h), and centrifuged (~2000 g). The resulting supernatant was removed, filtered (0.45 μm) and subjected to 14C activity analysis via liquid scintillation counter (LSC), dissolved organic carbon (DOC) analysis, and LC-MS-MS analysis. This extraction procedure was repeated 15 individual times, for both setups (A) and (B). To determine the distribution of the aged 14C labelled pesticide residues in the soil organic matter fractions, the soil samples were subject to humic and fulvic acids fractionations at cycles 0, 4, 10, and 15. The residual pesticide 14C activity associated with the humic, fulvic, and humin substances (organic fraction remaining in the soil) fractions was determined via LSC. The water-extracted residual 14C activity was significantly higher in the extracts of the dry/wet, compared to the wet/wet soil samples for both pesticides. The total extracted 14C activity in the dry/wet soil extracts accounted for 51.0% (ETD) and 15.4% (MBT) in contrast to 19.0% (ETD) and 4.7% (MBT) in the wet/wet extracts after 15 water extractions. LC-MS-MS analysis revealed the parent compound ETD 27.9 μg kg-1 soil (dry/wet) and 10.7 μg kg-1 soil (wet/wet), accounting for 3.45 and 1.35% of total parent compound

  5. Influence of alternating soil drying and wetting on the desorption and distribution of aged 14C-labeled pesticide residues in soil organic fractions

    NASA Astrophysics Data System (ADS)

    Jablonowski, N. D.; Mucha, M.; Thiele, B.; Hofmann, D.; Burauel, P.

    2012-04-01

    A laboratory experiment was conducted to evaluate the effect of alternating soil drying and wetting on the release of aged 14C-labeled pesticide residues and their distribution in soil organic fractions (humic acids, fulvic acids, and humin substances). The used soils (gleyic cambisol; Corg 1.2%, pH 7.2) were obtained from the upper soil layer of two individual outdoor lysimeter studies containing either environmentally long-term aged 14C residues of the herbicide ethidimuron (ETD; 0-10 cm depth; time of aging: 9 years) or methabenzthiazuron (MBT; 0-30 cm depth; time of aging: 17 years). Triplicate soil samples (10 g dry soil equivalents) were (A=dry/wet) previously dried (45° C) or (B=wet/wet) directly mixed with pure water (1+2, w:w), shaken (150 rpm, 1 h), and centrifuged (~2000 g). The resulting supernatant was removed, filtered (0.45 μm) and subjected to 14C activity analysis via liquid scintillation counter (LSC), dissolved organic carbon (DOC) analysis, and LC-MS-MS analysis. This extraction procedure was repeated 15 individual times, for both setups (A) and (B). To determine the distribution of the aged 14C labelled pesticide residues in the soil organic matter fractions, the soil samples were subject to humic and fulvic acids fractionations at cycles 0, 4, 10, and 15. The residual pesticide 14C activity associated with the humic, fulvic, and humin substances (organic fraction remaining in the soil) fractions was determined via LSC. The water-extracted residual 14C activity was significantly higher in the extracts of the dry/wet, compared to the wet/wet soil samples for both pesticides. The total extracted 14C activity in the dry/wet soil extracts accounted for 51.0% (ETD) and 15.4% (MBT) in contrast to 19.0% (ETD) and 4.7% (MBT) in the wet/wet extracts after 15 water extractions. LC-MS-MS analysis revealed the parent compound ETD 27.9 μg kg-1 soil (dry/wet) and 10.7 μg kg-1 soil (wet/wet), accounting for 3.45 and 1.35% of total parent compound

  6. Towards Personalized Medicine: Leveraging Patient Similarity and Drug Similarity Analytics

    PubMed Central

    Zhang, Ping; Wang, Fei; Hu, Jianying; Sorrentino, Robert

    2014-01-01

    The rapid adoption of electronic health records (EHR) provides a comprehensive source for exploratory and predictive analytic to support clinical decision-making. In this paper, we investigate how to utilize EHR to tailor treatments to individual patients based on their likelihood to respond to a therapy. We construct a heterogeneous graph which includes two domains (patients and drugs) and encodes three relationships (patient similarity, drug similarity, and patient-drug prior associations). We describe a novel approach for performing a label propagation procedure to spread the label information representing the effectiveness of different drugs for different patients over this heterogeneous graph. The proposed method has been applied on a real-world EHR dataset to help identify personalized treatments for hypercholesterolemia. The experimental results demonstrate the effectiveness of the approach and suggest that the combination of appropriate patient similarity and drug similarity analytics could lead to actionable insights for personalized medicine. Particularly, by leveraging drug similarity in combination with patient similarity, our method could perform well even on new or rarely used drugs for which there are few records of known past performance. PMID:25717413

  7. Towards personalized medicine: leveraging patient similarity and drug similarity analytics.

    PubMed

    Zhang, Ping; Wang, Fei; Hu, Jianying; Sorrentino, Robert

    2014-01-01

    The rapid adoption of electronic health records (EHR) provides a comprehensive source for exploratory and predictive analytic to support clinical decision-making. In this paper, we investigate how to utilize EHR to tailor treatments to individual patients based on their likelihood to respond to a therapy. We construct a heterogeneous graph which includes two domains (patients and drugs) and encodes three relationships (patient similarity, drug similarity, and patient-drug prior associations). We describe a novel approach for performing a label propagation procedure to spread the label information representing the effectiveness of different drugs for different patients over this heterogeneous graph. The proposed method has been applied on a real-world EHR dataset to help identify personalized treatments for hypercholesterolemia. The experimental results demonstrate the effectiveness of the approach and suggest that the combination of appropriate patient similarity and drug similarity analytics could lead to actionable insights for personalized medicine. Particularly, by leveraging drug similarity in combination with patient similarity, our method could perform well even on new or rarely used drugs for which there are few records of known past performance. PMID:25717413

  8. Effects of Wheat and Oat-Based Whole Grain Foods on Serum Lipoprotein Size and Distribution in Overweight Middle Aged People: A Randomised Controlled Trial

    PubMed Central

    Tighe, Paula; Duthie, Garry; Brittenden, Julie; Vaughan, Nicholas; Mutch, William; Simpson, William G.; Duthie, Susan; Horgan, Graham W.; Thies, Frank

    2013-01-01

    Introduction Epidemiological studies suggest three daily servings of whole-grain foods (WGF) might lower cardiovascular disease risk, at least partly by lowering serum lipid levels. We have assessed the effects of consuming three daily portions of wholegrain food (provided as wheat or a mixture of wheat and oats) on lipoprotein subclass size and concentration in a dietary randomised controlled trial involving middle aged healthy individuals. Methods After a 4-week run-in period on a refined diet, volunteers were randomly allocated to a control (refined diet), wheat, or wheat + oats group for 12 weeks. Our servings were determined in order to significantly increase the intakes of non starch polysaccharides to the UK Dietary Reference Value of 18 g per day in the whole grain groups (18.5 g and 16.8 g per day in the wheat and wheat + oats groups respectively in comparison with 11.3 g per day in the control group). Outcome measures were serum lipoprotein subclasses' size and concentration. Habitual dietary intake was assessed prior and during the intervention. Of the 233 volunteers recruited, 24 withdrew and 3 were excluded. Results At baseline, significant associations were found between lipoprotein size and subclasses' concentrations and some markers of cardiovascular risk such as insulin resistance, blood pressure and serum Inter cellular adhesion molecule 1 concentration. Furthermore, alcohol and vitamin C intake were positively associated with an anti-atherogenic lipoprotein profile, with regards to lipoprotein size and subclasses' distribution. However, none of the interventions with whole grain affected lipoprotein size and profile. Conclusion Our results indicate that three portions of wholegrain foods, irrelevant of the type (wheat or oat-based) do not reduce cardiovascular risk by beneficially altering the size and distribution of lipoprotein subclasses. Trial Registration www.Controlled-Trials.com ISRCTN 27657880. PMID:23940575

  9. Anal Human Papillomavirus Genotype Distribution in HIV-Infected Men Who Have Sex with Men by Geographical Origin, Age, and Cytological Status in a Spanish Cohort

    PubMed Central

    Torres, Montserrat; González, Cristina; del Romero, Jorge; Viciana, Pompeyo; Ocampo, Antonio; Rodríguez-Fortúnez, Patricia; Masiá, Mar; Blanco, José Ramón; Portilla, Joaquín; Rodríguez, Carmen; Hernández-Novoa, Beatriz; del Amo, Julia

    2013-01-01

    Knowledge of human papillomavirus (HPV) type distribution in populations at risk for anal cancer is needed. Here, we describe the anal HPV genotype distribution in a large Spanish cohort (Cohort of the Spanish HIV Research Network HPV [CoRIS-HPV]) of HIV-positive men who have sex with men (MSM) according to geographical origin, age, and cytological status. A cross-sectional analysis of baseline data from 1,439 HIV-infected MSM (2007 to 2012) was performed. Anal HPV genotyping was performed using the Linear Array HPV genotyping test. Descriptive analyses of subject characteristics, prevalences, and 95% confidence intervals (CI) were performed. The global prevalences of HPV, high-risk HPV (HR-HPV), and low-risk HPV (LR-HPV) types were 95.8%, 83.0%, and 72.7%, respectively. Among the HR-HPV types, HPV16 was the most common, followed by HPV59, -39, -51, -18, and -52. The prevalence of multiple HR-HPV infections was 58.5%. There were no differences in the crude analyses between Spanish and Latin-American MSM for most HPV types, and a peak in prevalence for most HPV types was seen in patients in their late thirties. Globally and by specific HPV groups, men with abnormal anal cytologies had a higher prevalence of infection than those with normal cytologies. This study has the largest number of HIV-positive MSM with HPV genotype data analyzed according to cytological status as far as we know. The information gained from this study can help with the design of anal cancer prevention strategies in HIV-positive patients. PMID:23966501

  10. Anal human papillomavirus genotype distribution in HIV-infected men who have sex with men by geographical origin, age, and cytological status in a Spanish cohort.

    PubMed

    Torres, Montserrat; González, Cristina; del Romero, Jorge; Viciana, Pompeyo; Ocampo, Antonio; Rodríguez-Fortúnez, Patricia; Masiá, Mar; Blanco, José Ramón; Portilla, Joaquín; Rodríguez, Carmen; Hernández-Novoa, Beatriz; del Amo, Julia; Ortiz, Marta

    2013-11-01

    Knowledge of human papillomavirus (HPV) type distribution in populations at risk for anal cancer is needed. Here, we describe the anal HPV genotype distribution in a large Spanish cohort (Cohort of the Spanish HIV Research Network HPV [CoRIS-HPV]) of HIV-positive men who have sex with men (MSM) according to geographical origin, age, and cytological status. A cross-sectional analysis of baseline data from 1,439 HIV-infected MSM (2007 to 2012) was performed. Anal HPV genotyping was performed using the Linear Array HPV genotyping test. Descriptive analyses of subject characteristics, prevalences, and 95% confidence intervals (CI) were performed. The global prevalences of HPV, high-risk HPV (HR-HPV), and low-risk HPV (LR-HPV) types were 95.8%, 83.0%, and 72.7%, respectively. Among the HR-HPV types, HPV16 was the most common, followed by HPV59, -39, -51, -18, and -52. The prevalence of multiple HR-HPV infections was 58.5%. There were no differences in the crude analyses between Spanish and Latin-American MSM for most HPV types, and a peak in prevalence for most HPV types was seen in patients in their late thirties. Globally and by specific HPV groups, men with abnormal anal cytologies had a higher prevalence of infection than those with normal cytologies. This study has the largest number of HIV-positive MSM with HPV genotype data analyzed according to cytological status as far as we know. The information gained from this study can help with the design of anal cancer prevention strategies in HIV-positive patients.

  11. THE LUMINOSITY, MASS, AND AGE DISTRIBUTIONS OF COMPACT STAR CLUSTERS IN M83 BASED ON HUBBLE SPACE TELESCOPE/WIDE FIELD CAMERA 3 OBSERVATIONS

    SciTech Connect

    Chandar, Rupali; Whitmore, Bradley C.; Mutchler, Max; Bond, Howard; Kim, Hwihyun; Kaleida, Catherine; Calzetti, Daniela; Saha, Abhijit; O'Connell, Robert; Balick, Bruce; Carollo, Marcella; Disney, Michael; Dopita, Michael A.; Frogel, Jay A.; Hall, Donald; Holtzman, Jon A.; Kimble, Randy A.; McCarthy, Patrick; Paresce, Francesco; Silk, Joe

    2010-08-10

    The newly installed Wide Field Camera 3 (WFC3) on the Hubble Space Telescope has been used to obtain multi-band images of the nearby spiral galaxy M83. These new observations are the deepest and highest resolution images ever taken of a grand-design spiral, particularly in the near-ultraviolet, and allow us to better differentiate compact star clusters from individual stars and to measure the luminosities of even faint clusters in the U band. We find that the luminosity function (LF) for clusters outside of the very crowded starburst nucleus can be approximated by a power law, dN/dL {proportional_to} L {sup {alpha}}, with {alpha} = -2.04 {+-} 0.08, down to M{sub V} {approx} -5.5. We test the sensitivity of the LF to different selection techniques, filters, binning, and aperture correction determinations, and find that none of these contribute significantly to uncertainties in {alpha}. We estimate ages and masses for the clusters by comparing their measured UBVI, H{alpha} colors with predictions from single stellar population models. The age distribution of the clusters can be approximated by a power law, dN/d{tau} {proportional_to} {tau}{sup {gamma}}, with {gamma} = -0.9 {+-} 0.2, for M {approx}> few x 10{sup 3} M {sub sun} and {tau} {approx}< 4 x 10{sup 8} yr. This indicates that clusters are disrupted quickly, with {approx}80%-90% disrupted each decade in age over this time. The mass function of clusters over the same M-{tau} range is a power law, dN/dM {proportional_to} M {sup {beta}}, with {beta} = -1.94 {+-} 0.16, and does not have bends or show curvature at either high or low masses. Therefore, we do not find evidence for a physical upper mass limit, M{sub C} , or for the earlier disruption of lower mass clusters when compared with higher mass clusters, i.e., mass-dependent disruption. We briefly discuss these implications for the formation and disruption of the clusters.

  12. Age distribution of Ocean Drill sites across the Central Walvis Ridge indicates plate boundary control of plume volcanism in the South Atlantic

    NASA Astrophysics Data System (ADS)

    O'Connor, John M.; Jokat, Wilfried

    2015-08-01

    The Tristan-Gough hotspot trail on the African plate consists of the Walvis Ridge and a younger province of seamounts and islands. In order to determine the relative motion between the African plate and the Tristan-Gough hotspot it is essential to resolve changes in the age and morphology of the Walvis Ridge. A significant problem is, however, to establish how the vigor and flow of hotspot material to the mid-ocean ridge constructed the Walvis Ridge. We have addressed this issue by measuring an 40Ar/39Ar stratigraphy at three sites across the central Walvis Ridge sampled by Ocean Drilling (DSDP Leg 74). The age-distance relation of volcanism, together with geophysical, geochemical and paleodepth information, suggests collectively that hotspot volcanism was occurring locally c. 72 Ma on an elevated segment of the mid-ocean ridge located close to the Tristan-Gough hotspot. As the mid-ocean ridge migrated away from the hotspot (c. 36 km/Ma) between c. 72 Ma and 68 Ma, hotspot material continued flowing to the mid-ocean ridge and the Walvis Ridge shoaled rapidly (c. 500 m/Ma) to the west, on seafloor that might have been subsiding at a rate consistent with normal crustal cooling. This apparent correlation points to the possibility of an inverse relation between the volume flux of hotspot volcanism and the distance between the mid-ocean ridge and the Tristan-Gough hotspot. We infer that since c. 93 Ma the geometry and motion of the mid-ocean ridge determined where the hotspot material that built the Walvis Ridge was channeled to the plate surface. Furthermore, interplay between hotspot flow, and the changing geometry of the mid-ocean ridge as it migrated relative to the Tristan-Gough hotspot, might explain the age and morphology of the Walvis Ridge. Our finding provides further evidence that the distribution of hotspot volcanism in the southeast Atlantic expresses interaction between deep mantle (plume) and shallow plate tectonic and asthenosphere processes.

  13. Privacy-preserving matching of similar patients.

    PubMed

    Vatsalan, Dinusha; Christen, Peter

    2016-02-01

    The identification of similar entities represented by records in different databases has drawn considerable attention in many application areas, including in the health domain. One important type of entity matching application that is vital for quality healthcare analytics is the identification of similar patients, known as similar patient matching. A key component of identifying similar records is the calculation of similarity of the values in attributes (fields) between these records. Due to increasing privacy and confidentiality concerns, using the actual attribute values of patient records to identify similar records across different organizations is becoming non-trivial because the attributes in such records often contain highly sensitive information such as personal and medical details of patients. Therefore, the matching needs to be based on masked (encoded) values while being effective and efficient to allow matching of large databases. Bloom filter encoding has widely been used as an efficient masking technique for privacy-preserving matching of string and categorical values. However, no work on Bloom filter-based masking of numerical data, such as integer (e.g. age), floating point (e.g. body mass index), and modulus (numbers wrap around upon reaching a certain value, e.g. date and time), which are commonly required in the health domain, has been presented in the literature. We propose a framework with novel methods for masking numerical data using Bloom filters, thereby facilitating the calculation of similarities between records. We conduct an empirical study on publicly available real-world datasets which shows that our framework provides efficient masking and achieves similar matching accuracy compared to the matching of actual unencoded patient records.

  14. Privacy-preserving matching of similar patients.

    PubMed

    Vatsalan, Dinusha; Christen, Peter

    2016-02-01

    The identification of similar entities represented by records in different databases has drawn considerable attention in many application areas, including in the health domain. One important type of entity matching application that is vital for quality healthcare analytics is the identification of similar patients, known as similar patient matching. A key component of identifying similar records is the calculation of similarity of the values in attributes (fields) between these records. Due to increasing privacy and confidentiality concerns, using the actual attribute values of patient records to identify similar records across different organizations is becoming non-trivial because the attributes in such records often contain highly sensitive information such as personal and medical details of patients. Therefore, the matching needs to be based on masked (encoded) values while being effective and efficient to allow matching of large databases. Bloom filter encoding has widely been used as an efficient masking technique for privacy-preserving matching of string and categorical values. However, no work on Bloom filter-based masking of numerical data, such as integer (e.g. age), floating point (e.g. body mass index), and modulus (numbers wrap around upon reaching a certain value, e.g. date and time), which are commonly required in the health domain, has been presented in the literature. We propose a framework with novel methods for masking numerical data using Bloom filters, thereby facilitating the calculation of similarities between records. We conduct an empirical study on publicly available real-world datasets which shows that our framework provides efficient masking and achieves similar matching accuracy compared to the matching of actual unencoded patient records. PMID:26707453

  15. Age distributions of sea otters found dead in Prince William Sound, Alaska, following the Exxon Valdez oil spill. Marine mammal study 6-15. Exxon Valdez oil spill state/federal natural resource damage assessment final report

    SciTech Connect

    Monson, D.H.; Ballachey, B.

    1995-06-01

    Age distribution of sea otters (Enhydra lutris) found dead on beaches in western Prince William Sound Alaska, from 1976 to 1984, were compared to those of sea otters found dead from 1989 to 1993, following the Exxon Valdez oil spill. The age distribution of sea otters recovered in western Prince William Sound prior to the spill was bimodal and composed of primarily young and old animals. The high proportion of prime-age otters recovered immediately following the spill indicates significant losses occurred within a segment of the population which normally experiences very low mortality. The high proportion of prime-age otters recovered in 1990-1991 may be evidence of a prolonged, spill-related effect on the western Prince William Sound sea otter population.

  16. Measuring structural similarity in large online networks.

    PubMed

    Shi, Yongren; Macy, Michael

    2016-09-01

    Structural similarity based on bipartite graphs can be used to detect meaningful communities, but the networks have been tiny compared to massive online networks. Scalability is important in applications involving tens of millions of individuals with highly skewed degree distributions. Simulation analysis holding underlying similarity constant shows that two widely used measures - Jaccard index and cosine similarity - are biased by the distribution of out-degree in web-scale networks. However, an alternative measure, the Standardized Co-incident Ratio (SCR), is unbiased. We apply SCR to members of Congress, musical artists, and professional sports teams to show how massive co-following on Twitter can be used to map meaningful affiliations among cultural entities, even in the absence of direct connections to one another. Our results show how structural similarity can be used to map cultural alignments and demonstrate the potential usefulness of social media data in the study of culture, politics, and organizations across the social and behavioral sciences. PMID:27480374

  17. Predicting spatial similarity of freshwater fish biodiversity

    PubMed Central

    Azaele, Sandro; Muneepeerakul, Rachata; Maritan, Amos; Rinaldo, Andrea; Rodriguez-Iturbe, Ignacio

    2009-01-01

    A major issue in modern ecology is to understand how ecological complexity at broad scales is regulated by mechanisms operating at the organismic level. What specific underlying processes are essential for a macroecological pattern to emerge? Here, we analyze the analytical predictions of a general model suitable for describing the spatial biodiversity similarity in river ecosystems, and benchmark them against the empirical occurrence data of freshwater fish species collected in the Mississippi–Missouri river system. Encapsulating immigration, emigration, and stochastic noise, and without resorting to species abundance data, the model is able to reproduce the observed probability distribution of the Jaccard similarity index at any given distance. In addition to providing an excellent agreement with the empirical data, this approach accounts for heterogeneities of different subbasins, suggesting a strong dependence of biodiversity similarity on their respective climates. Strikingly, the model can also predict the actual probability distribution of the Jaccard similarity index for any distance when considering just a relatively small sample. The proposed framework supports the notion that simplified macroecological models are capable of predicting fundamental patterns—a theme at the heart of modern community ecology. PMID:19359481

  18. The Neogene and Quaternary Clay-with-flints north and south of the English Channel: comparisons of distribution, age, genetic processes and geodynamics

    NASA Astrophysics Data System (ADS)

    Quesnel, Florence; Catt, John; Laignel, Benoît; Bourdillon, Chantal; Meyer, Robert

    2003-02-01

    Weathered residual accumulations termed Clay-with-flints (Argiles à silex) overlying Cretaceous deposits are widespread in southern England and northwestern France. Geological and pedological studies and some field surveys indicate their distribution, nature, age and origin. In France, the microfaunas preserved in the hollow flints of the Clay-with-flints demonstrate the preservation of the parent Chalk stratigraphy in the sections studied, i.e. the Clay-with-flints corresponds to in situ weathering profiles. However, in England and in France, an important part of the clay component is derived from a thin veneer of basal Tertiary sediment overlying sub-Tertiary marine erosion surfaces of various Palaeogene transgressions. In England as in France, the youngest generation of Clay-with-flints can be dated from Late Pliocene to Quaternary. It formed after removal of different Cenozoic deposits on many plateaus and during the downcutting of Pleistocene rivers. The most visible effect of subsequent weathering profile development is irregular dissolution of the underlying Chalk to produce deep karstic pipes into which the Clay-with-flints has slumped; other pedological processes include rubification, clay illuviation and cryoturbation. Clay-with-flints also provides evidence of Quaternary palaeoenvironments, Cenozoic continental palaeosurfaces, and their vertical deformation.

  19. Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant stars. V. Evidence for a wide age distribution and a complex MDF

    NASA Astrophysics Data System (ADS)

    Bensby, T.; Yee, J. C.; Feltzing, S.; Johnson, J. A.; Gould, A.; Cohen, J. G.; Asplund, M.; Meléndez, J.; Lucatello, S.; Han, C.; Thompson, I.; Gal-Yam, A.; Udalski, A.; Bennett, D. P.; Bond, I. A.; Kohei, W.; Sumi, T.; Suzuki, D.; Suzuki, K.; Takino, S.; Tristram, P.; Yamai, N.; Yonehara, A.

    2013-01-01

    Based on high-resolution spectra obtained during gravitational microlensing events we present a detailed elemental abundance analysis of 32 dwarf and subgiant stars in the Galactic bulge. Combined with the sample of 26 stars from the previous papers in this series, we now have 58 microlensed bulge dwarfs and subgiants that have been homogeneously analysed. The main characteristics of the sample and the findings that can be drawn are: (i) the metallicity distribution (MDF) is wide and spans all metallicities between [Fe/H] = -1.9 to +0.6; (ii) the dip in the MDF around solar metallicity that was apparent in our previous analysis of a smaller sample (26 microlensed stars) is no longer evident; instead it has a complex structure and indications of multiple components are starting to emerge. A tentative interpretation is that there could be different stellar populations at interplay, each with a different scale height: the thin disk, the thick disk, and a bar population; (iii) the stars with [Fe/H] ≲ -0.1 are old with ages between 10 and 12 Gyr; (iv) the metal-rich stars with [Fe/H] ≳ -0.1 show a wide variety of ages, ranging from 2 to 12 Gyr with a distribution that has a dominant peak around 4-5 Gyr and a tail towards higher ages; (v) there are indications in the [α/Fe]-[Fe/H] abundance trends that the "knee" occurs around [Fe/H] = -0.3to -0.2, which is a slightly higher metallicity as compared to the "knee" for the local thick disk. This suggests that the chemical enrichment of the metal-poor bulge has been somewhat faster than what is observed for the local thick disk. The results from the microlensed bulge dwarf stars in combination with other findings in the literature, in particular the evidence that the bulge has cylindrical rotation, indicate that the Milky Way could be an almost pure disk galaxy. The bulge would then just be a conglomerate of the other Galactic stellar populations (thin disk, thick disk, halo, and ...?), residing together in the central

  20. Distribution, diet, and energetic condition of age-0 walleye pollock (Gadus chalcogrammus) and pacific cod (Gadus macrocephalus) inhabiting the Gulf of Alaska

    NASA Astrophysics Data System (ADS)

    Moss, Jamal H.; Zaleski, Marilyn F.; Heintz, Ron A.

    2016-10-01

    Walleye pollock (Gadus chalcogrammus) and Pacific cod (Gadus macrocephalus) are commercially and ecologically important species in Alaska waters. Little is known about their ecology after transitioning from larvae to free swimming fish until settlement to nursery habitats in the eastern Gulf of Alaska. Differences in the distribution, diet, body size, and energetic status between the eastern and central Gulf of Alaska were investigated during summer months to better understand regional and interspecific differences in life history and ecology. The composition of zooplankton prey in the diets of walleye pollock and Pacific cod inhabiting shelf waters was more varied relative to those inhabiting the slope and basin. Body condition and total energy content of Pacific cod was greater than walleye pollock, however total energy content increased with length at a similar rate for both species. Walleye pollock inhabiting continental slope waters had higher energy stores relative to those inhabiting the continental shelf and basin, indicating an energetic advantage for individuals remaining off the shelf during summer months or potentially the advection of fish with higher energy reserves off of the shelf. Previous studies have documented the importance of energy stores for surviving winter and future studies should focus on understanding the mechanisms influencing lipid storage and somatic growth for walleye pollock and Pacific cod inhabiting the eastern and central Gulf of Alaska.

  1. Toward a Unified Theory of Similarity and Recognition.

    ERIC Educational Resources Information Center

    Ashby, F. Gregory; Perrin, Nancy A.

    1988-01-01

    Using general recognition theory, a new theory of similarity is developed, postulating that perceived similarity is determined by distributional overlap. This theory is related to existing theories of similarity. Three experiments using a total of 19 university students are presented, testing the empirical validity of the theory. (SLD)

  2. Similarity, invariance, and musical variation.

    PubMed

    McAdams, S; Matzkin, D

    2001-06-01

    Perceptual similarity underlies a number of important psychological properties of musical materials, including perceptual invariance under transformation, categorization, recognition, and the sense of familiarity. Mental processes involved in the perception of musical similarity may be an integral part of the functional logic of music composition and thus underly important aspects of musical experience. How much and in what ways can musical materials be varied and still be considered as perceptually related or as belonging to the same category? The notions of musical material, musical variation, perceptual similarity and invariance, and form-bearing dimensions are considered in this light. Recent work on similarity perception has demonstrated that the transformation space for a given musical material is limited by several factors ranging from degree of match of the values of auditory attributes of the events composing the sequences to their relations of various levels of abstraction and to the degree that the transformation respects the grammar of the musical system within which the material was composed. These notions and results are considered in the light of future directions of research, particularly concerning the role of similarity and invariance in the understanding of musical form during listening.

  3. Similarity, invariance, and musical variation.

    PubMed

    McAdams, S; Matzkin, D

    2001-06-01

    Perceptual similarity underlies a number of important psychological properties of musical materials, including perceptual invariance under transformation, categorization, recognition, and the sense of familiarity. Mental processes involved in the perception of musical similarity may be an integral part of the functional logic of music composition and thus underly important aspects of musical experience. How much and in what ways can musical materials be varied and still be considered as perceptually related or as belonging to the same category? The notions of musical material, musical variation, perceptual similarity and invariance, and form-bearing dimensions are considered in this light. Recent work on similarity perception has demonstrated that the transformation space for a given musical material is limited by several factors ranging from degree of match of the values of auditory attributes of the events composing the sequences to their relations of various levels of abstraction and to the degree that the transformation respects the grammar of the musical system within which the material was composed. These notions and results are considered in the light of future directions of research, particularly concerning the role of similarity and invariance in the understanding of musical form during listening. PMID:11458867

  4. Quantifying Similarity in Seismic Polarizations

    NASA Astrophysics Data System (ADS)

    Eaton, D. W. S.; Jones, J. P.; Caffagni, E.

    2015-12-01

    Measuring similarity in seismic attributes can help identify tremor, low S/N signals, and converted or reflected phases, in addition to diagnosing site noise and sensor misalignment in arrays. Polarization analysis is a widely accepted method for studying the orientation and directional characteristics of seismic phases via. computed attributes, but similarity is ordinarily discussed using qualitative comparisons with reference values. Here we introduce a technique for quantitative polarization similarity that uses weighted histograms computed in short, overlapping time windows, drawing on methods adapted from the image processing and computer vision literature. Our method accounts for ambiguity in azimuth and incidence angle and variations in signal-to-noise (S/N) ratio. Using records of the Mw=8.3 Sea of Okhotsk earthquake from CNSN broadband sensors in British Columbia and Yukon Territory, Canada, and vertical borehole array data from a monitoring experiment at Hoadley gas field, central Alberta, Canada, we demonstrate that our method is robust to station spacing. Discrete wavelet analysis extends polarization similarity to the time-frequency domain in a straightforward way. Because histogram distance metrics are bounded by [0 1], clustering allows empirical time-frequency separation of seismic phase arrivals on single-station three-component records. Array processing for automatic seismic phase classification may be possible using subspace clustering of polarization similarity, but efficient algorithms are required to reduce the dimensionality.

  5. Sibling similarity in family formation.

    PubMed

    Raab, Marcel; Fasang, Anette Eva; Karhula, Aleksi; Erola, Jani

    2014-12-01

    Sibling studies have been widely used to analyze the impact of family background on socioeconomic and, to a lesser extent, demographic outcomes. We contribute to this literature with a novel research design that combines sibling comparisons and sequence analysis to analyze longitudinal family-formation trajectories of siblings and unrelated persons. This allows us to scrutinize in a more rigorous way whether sibling similarity exists in family-formation trajectories and whether siblings' shared background characteristics, such as parental education and early childhood family structure, can account for similarity in family formation. We use Finnish register data from 1987 through 2007 to construct longitudinal family-formation trajectories in young adulthood for siblings and unrelated dyads (N = 14,257 dyads). Findings show that family formation is moderately but significantly more similar for siblings than for unrelated dyads, also after controlling for crucial parental background characteristics. Shared parental background characteristics add surprisingly little to account for sibling similarity in family formation. Instead, gender and the respondents' own education are more decisive forces in the stratification of family formation. Yet, family internal dynamics seem to reinforce this stratification such that siblings have a higher probability to experience similar family-formation patterns. In particular, patterns that correspond with economic disadvantage are concentrated within families. This is in line with a growing body of research highlighting the importance of family structure in the reproduction of social inequality.

  6. Earthquake detection through computationally efficient similarity search.

    PubMed

    Yoon, Clara E; O'Reilly, Ossian; Bergen, Karianne J; Beroza, Gregory C

    2015-12-01

    Seismology is experiencing rapid growth in the quantity of data, which has outpaced the development of processing algorithms. Earthquake detection-identification of seismic events in continuous data-is a fundamental operation for observational seismology. We developed an efficient method to detect earthquakes using waveform similarity that overcomes the disadvantages of existing detection methods. Our method, called Fingerprint And Similarity Thresholding (FAST), can analyze a week of continuous seismic waveform data in less than 2 hours, or 140 times faster than autocorrelation. FAST adapts a data mining algorithm, originally designed to identify similar audio clips within large databases; it first creates compact "fingerprints" of waveforms by extracting key discriminative features, then groups similar fingerprints together within a database to facilitate fast, scalable search for similar fingerprint pairs, and finally generates a list of earthquake detections. FAST detected most (21 of 24) cataloged earthquakes and 68 uncataloged earthquakes in 1 week of continuous data from a station located near the Calaveras Fault in central California, achieving detection performance comparable to that of autocorrelation, with some additional false detections. FAST is expected to realize its full potential when applied to extremely long duration data sets over a distributed network of seismic stations. The widespread application of FAST has the potential to aid in the discovery of unexpected seismic signals, improve seismic monitoring, and promote a greater understanding of a variety of earthquake processes. PMID:26665176

  7. Earthquake detection through computationally efficient similarity search

    PubMed Central

    Yoon, Clara E.; O’Reilly, Ossian; Bergen, Karianne J.; Beroza, Gregory C.

    2015-01-01

    Seismology is experiencing rapid growth in the quantity of data, which has outpaced the development of processing algorithms. Earthquake detection—identification of seismic events in continuous data—is a fundamental operation for observational seismology. We developed an efficient method to detect earthquakes using waveform similarity that overcomes the disadvantages of existing detection methods. Our method, called Fingerprint And Similarity Thresholding (FAST), can analyze a week of continuous seismic waveform data in less than 2 hours, or 140 times faster than autocorrelation. FAST adapts a data mining algorithm, originally designed to identify similar audio clips within large databases; it first creates compact “fingerprints” of waveforms by extracting key discriminative features, then groups similar fingerprints together within a database to facilitate fast, scalable search for similar fingerprint pairs, and finally generates a list of earthquake detections. FAST detected most (21 of 24) cataloged earthquakes and 68 uncataloged earthquakes in 1 week of continuous data from a station located near the Calaveras Fault in central California, achieving detection performance comparable to that of autocorrelation, with some additional false detections. FAST is expected to realize its full potential when applied to extremely long duration data sets over a distributed network of seismic stations. The widespread application of FAST has the potential to aid in the discovery of unexpected seismic signals, improve seismic monitoring, and promote a greater understanding of a variety of earthquake processes. PMID:26665176

  8. Earthquake detection through computationally efficient similarity search.

    PubMed

    Yoon, Clara E; O'Reilly, Ossian; Bergen, Karianne J; Beroza, Gregory C

    2015-12-01

    Seismology is experiencing rapid growth in the quantity of data, which has outpaced the development of processing algorithms. Earthquake detection-identification of seismic events in continuous data-is a fundamental operation for observational seismology. We developed an efficient method to detect earthquakes using waveform similarity that overcomes the disadvantages of existing detection methods. Our method, called Fingerprint And Similarity Thresholding (FAST), can analyze a week of continuous seismic waveform data in less than 2 hours, or 140 times faster than autocorrelation. FAST adapts a data mining algorithm, originally designed to identify similar audio clips within large databases; it first creates compact "fingerprints" of waveforms by extracting key discriminative features, then groups similar fingerprints together within a database to facilitate fast, scalable search for similar fingerprint pairs, and finally generates a list of earthquake detections. FAST detected most (21 of 24) cataloged earthquakes and 68 uncataloged earthquakes in 1 week of continuous data from a station located near the Calaveras Fault in central California, achieving detection performance comparable to that of autocorrelation, with some additional false detections. FAST is expected to realize its full potential when applied to extremely long duration data sets over a distributed network of seismic stations. The widespread application of FAST has the potential to aid in the discovery of unexpected seismic signals, improve seismic monitoring, and promote a greater understanding of a variety of earthquake processes.

  9. A REST-FRAME OPTICAL VIEW ON z {approx} 4 GALAXIES. I. COLOR AND AGE DISTRIBUTIONS FROM DEEP IRAC PHOTOMETRY OF THE IUDF10 AND GOODS SURVEYS

    SciTech Connect

    Oesch, P. A.; Illingworth, G. D.; Gonzalez, V.; Holden, B. P.; Magee, D.; Trenti, M.; Van Dokkum, P. G.

    2013-08-01

    We present a study of rest-frame UV-to-optical color distributions for z {approx} 4 galaxies based on the combination of deep HST/ACS+WFC3/IR data with Spitzer/IRAC imaging. In particular, we use new, ultra-deep data from the IRAC Ultradeep Field program (IUDF10), together with previous, public IRAC data over the GOODS fields. Our sample contains a total of {approx}2600 galaxies selected as B-dropout Lyman-break Galaxies in the HUDF and its deep parallel field HUDF09-2, as well as GOODS-North/South. This sample is used to investigate the UV continuum slopes {beta} and Balmer break colors (J{sub 125} - [4.5]) as a function of rest-frame optical luminosity (using [4.5] to avoid optical emission lines). We find that galaxies at M{sub z} < -21.5 (roughly corresponding to L{sup *}{sub z{approx}4}) are significantly redder than their lower luminosity counterparts. The UV continuum slopes and the J{sub 125} - [4.5] colors are well correlated, indicating that the dust reddening at these redshifts is better described by an SMC-like extinction curve, rather than the typically assumed Calzetti reddening. After dust correction, we find that the galaxy population shows mean stellar population ages in the range 10{sup 8.5} to 10{sup 9} yr, with a dispersion of {approx}0.5 dex, and only weak trends as a function of luminosity. Only a small fraction of galaxies shows Balmer break colors consistent with extremely young ages, younger than 100 Myr. Under the assumption of smooth star-formation histories, this fraction is 12%-19% for galaxies at M{sub z} < -19.75. Our results are consistent with a gradual build-up of stars and dust in galaxies at z > 4 with only a small fraction of stars being formed in short, intense bursts of star-formation.

  10. Baseline prevalence and type distribution of human papillomavirus in healthy Chinese women aged 18-25 years enrolled in a clinical trial.

    PubMed

    Zhao, Fang-Hui; Zhu, Feng-Cai; Chen, Wen; Li, Juan; Hu, Yue-Mei; Hong, Ying; Zhang, Yi-Ju; Pan, Qin-Jing; Zhu, Jia-Hong; Zhang, Xun; Chen, Yong; Tang, Haiwen; Zhang, Helen; Durand, Christelle; Datta, Sanjoy K; Struyf, Frank; Bi, Dan

    2014-12-01

    Baseline human papillomavirus (HPV) prevalence and type distribution were evaluated in young Chinese women enrolled in a clinical trial of an HPV vaccine (ClinicalTrials.gov registration NCT00779766). Cervical specimens and blood samples were collected at baseline from women aged 18-25 years (n = 6,051) from four sites across Jiangsu province. Cervical specimens were tested for HPV DNA by SPF10 PCR-DEIA-LiPA25 version 1, and HPV-16/18 type-specific polymerase chain reaction. Anti-HPV-16 and anti-HPV-18 antibody titres were quantified by enzyme-linked immunosorbent assay. At baseline, 15.3% of women were DNA positive for any of 14 HPV high-risk (hr) types (HPV-16/18/31/33/35/39/45/51/52/56/58/59/66/68). The most commonly detected hrHPV types in cervical specimens were HPV-52 (4.0%) and HPV-16 (3.7%). High-risk HPV DNA-positivity increased with severity of cytological abnormalities: 39.3% in atypical squamous cells of undetermined significance, 85.0% in low-grade squamous intraepithelial lesions and 97.8% in high-grade squamous intraepithelial lesions (HSIL). The hrHPV types most frequently detected in HSIL were HPV-16 (63.0%), HPV-18 (17.4%), HPV-52 (17.4%), HPV-58 (15.2%) and HPV-33 (15.2%). The hrHPV types most frequently detected in cervical intraepithelial neoplasia 2+ were HPV-16 (66.1%), HPV-33 (16.1%), HPV-52 (16.1%), HPV-58 (14.5%) and HPV-51 (11.3%). Multiple hrHPV infections were reported for 24.4% of hrHPV DNA positive women. Regardless of baseline HPV DNA status, 30.5% and 16.0% of subjects were initially seropositive for anti-HPV-16 and anti-HPV-18, respectively. In conclusion, the high baseline seropositivity rate and intermediate prevalence of cervical hrHPV types in Chinese women aged 18-25 years underlines the importance of early HPV vaccination in this population.

  11. Transformation and alignment in similarity.

    PubMed

    Hodgetts, Carl J; Hahn, Ulrike; Chater, Nick

    2009-10-01

    This paper contrasts two structural accounts of psychological similarity: structural alignment (SA) and Representational Distortion (RD). SA proposes that similarity is determined by how readily the structures of two objects can be brought into alignment; RD measures similarity by the complexity of the transformation that "distorts" one representation into the other. We assess RD by defining a simple coding scheme of psychological transformations for the experimental materials. In two experiments, this "concrete" version of RD provides compelling fits of the data and compares favourably with SA. Finally, stepping back from particular models, we argue that perceptual theory suggests that transformations and alignment processes should generally be viewed as complementary, in contrast to the current distinction in the literature. PMID:19720370

  12. Age, Growth and Spatial Distribution of the Life Stages of the Shortfin Mako, Isurus oxyrinchus (Rafinesque, 1810) Caught in the Western and Central Atlantic.

    PubMed

    Barreto, Rodrigo R; de Farias, Wialla K T; Andrade, Humber; Santana, Francisco M; Lessa, Rosangela

    2016-01-01

    The shortfin mako (Isurus oxyrinchus) is a highly migratory pelagic shark that preferentially inhabits oceanic regions in practically all oceans. The wide distribution range of this species renders it susceptible to coastal and oceanic fishing operations. The International Union for Conservation of Nature (IUCN) and the International Commission for the Conservation of Atlantic Tunas (ICCAT) consider this species to be highly vulnerable, especially due to its biological parameters, which are different from those of other sharks that occupy the same niche (e.g., Prionace glauca). Consequently, considerable declines in abundance have been detected over various parts of its range, most of which are linked to oceanic longline fishing. The species has conflicting life history parameters in studies conducted in the last 30 years, especially with regard to age and growth. The main discrepancies regard the interpretation of the periodicity of the deposition of band pairs (BPs) on vertebrae and the possibility of ontogenetic variations in growth. Shortfin mako sharks (n = 1325) were sampled by onboard observers of the Brazilian chartered pelagic longline fleet based in northeast Brazil from 2005 to 2011. Lengths were 79 to 250 and 73 to 296 cm (fork length, FL) for males and females, respectively, with a statistically significant difference in size between sexes and differences in the proportion of individuals in each size class. The onboard observers collected a subsample of vertebrae (n = 467), only 234 of which were suitable for analyses. Reliability between readings was satisfactory. However, it was not possible to validate periodicity in the formation of age bands in the sample. Thus, the von Bertalanffy growth function was used to calculate growth rates for the species through the interpretation of BPs in different scenarios: one BP per year (s1), two BPs per year (s2) and two BPs per year until five years of life (s3). Growth parameters varied for both females (Linf

  13. Age, Growth and Spatial Distribution of the Life Stages of the Shortfin Mako, Isurus oxyrinchus (Rafinesque, 1810) Caught in the Western and Central Atlantic

    PubMed Central

    Barreto, Rodrigo R.; de Farias, Wialla K. T.; Andrade, Humber; Santana, Francisco M.; Lessa, Rosangela

    2016-01-01

    The shortfin mako (Isurus oxyrinchus) is a highly migratory pelagic shark that preferentially inhabits oceanic regions in practically all oceans. The wide distribution range of this species renders it susceptible to coastal and oceanic fishing operations. The International Union for Conservation of Nature (IUCN) and the International Commission for the Conservation of Atlantic Tunas (ICCAT) consider this species to be highly vulnerable, especially due to its biological parameters, which are different from those of other sharks that occupy the same niche (e.g., Prionace glauca). Consequently, considerable declines in abundance have been detected over various parts of its range, most of which are linked to oceanic longline fishing. The species has conflicting life history parameters in studies conducted in the last 30 years, especially with regard to age and growth. The main discrepancies regard the interpretation of the periodicity of the deposition of band pairs (BPs) on vertebrae and the possibility of ontogenetic variations in growth. Shortfin mako sharks (n = 1325) were sampled by onboard observers of the Brazilian chartered pelagic longline fleet based in northeast Brazil from 2005 to 2011. Lengths were 79 to 250 and 73 to 296 cm (fork length, FL) for males and females, respectively, with a statistically significant difference in size between sexes and differences in the proportion of individuals in each size class. The onboard observers collected a subsample of vertebrae (n = 467), only 234 of which were suitable for analyses. Reliability between readings was satisfactory. However, it was not possible to validate periodicity in the formation of age bands in the sample. Thus, the von Bertalanffy growth function was used to calculate growth rates for the species through the interpretation of BPs in different scenarios: one BP per year (s1), two BPs per year (s2) and two BPs per year until five years of life (s3). Growth parameters varied for both females (Linf

  14. Age, Growth and Spatial Distribution of the Life Stages of the Shortfin Mako, Isurus oxyrinchus (Rafinesque, 1810) Caught in the Western and Central Atlantic.

    PubMed

    Barreto, Rodrigo R; de Farias, Wialla K T; Andrade, Humber; Santana, Francisco M; Lessa, Rosangela

    2016-01-01

    The shortfin mako (Isurus oxyrinchus) is a highly migratory pelagic shark that preferentially inhabits oceanic regions in practically all oceans. The wide distribution range of this species renders it susceptible to coastal and oceanic fishing operations. The International Union for Conservation of Nature (IUCN) and the International Commission for the Conservation of Atlantic Tunas (ICCAT) consider this species to be highly vulnerable, especially due to its biological parameters, which are different from those of other sharks that occupy the same niche (e.g., Prionace glauca). Consequently, considerable declines in abundance have been detected over various parts of its range, most of which are linked to oceanic longline fishing. The species has conflicting life history parameters in studies conducted in the last 30 years, especially with regard to age and growth. The main discrepancies regard the interpretation of the periodicity of the deposition of band pairs (BPs) on vertebrae and the possibility of ontogenetic variations in growth. Shortfin mako sharks (n = 1325) were sampled by onboard observers of the Brazilian chartered pelagic longline fleet based in northeast Brazil from 2005 to 2011. Lengths were 79 to 250 and 73 to 296 cm (fork length, FL) for males and females, respectively, with a statistically significant difference in size between sexes and differences in the proportion of individuals in each size class. The onboard observers collected a subsample of vertebrae (n = 467), only 234 of which were suitable for analyses. Reliability between readings was satisfactory. However, it was not possible to validate periodicity in the formation of age bands in the sample. Thus, the von Bertalanffy growth function was used to calculate growth rates for the species through the interpretation of BPs in different scenarios: one BP per year (s1), two BPs per year (s2) and two BPs per year until five years of life (s3). Growth parameters varied for both females (Linf

  15. Older Patients with Myeloma Derive Similar Benefit from Autologous Transplantation

    PubMed Central

    Sharma, Manish; Zhang, Mei-Jie; Zhong, Xiaobo; Abidi, Muneer H.; Akpek, Görgün; Bacher, Ulrike; Callander, Natalie S.; Dispenzieri, Angela; Freytes, César O.; Fung, Henry C.; Gale, Robert Peter; Gasparetto, Cristina; Gibson, John; Holmberg, Leona A.; Kindwall-Keller, Tamila L.; Klumpp, Thomas R.; Krishnan, Amrita Y.; Landau, Heather J.; Lazarus, Hillard M.; Lonial, Sagar; Maiolino, Angelo; Marks, David I.; Mehta, Paulette; Med, Joseph R. Mikhael; Nishihori, Taiga; Olsson, Richard; Ramanathan, Muthalagu; Roy, Vivek; Savani, Bipin N.; Schouten, Harry C.; Scott, Emma; Tay, Jason; To, Luen Bik; Vesole, David H.; Vogl, Dan T.; Hari, Parameswaran

    2014-01-01

    Autologous hematopoietic cell transplantation (AHCT) for plasma cell myeloma is performed less often in people >70 years old than in people ≤70 years old. We analyzed 11,430 AHCT recipients for plasma cell myeloma prospectively reported to the Center for International Blood and Marrow Transplant Research between 2008 and 2011, representing the majority of US AHCT activity during this period. Survival (OS) was compared in 3 cohorts: ages 18 to 59 years (n = 5818), 60 to 69 years (n = 4666), and >70 years (n = 946). Median OS was not reached for any cohort. In multivariate analysis, increasing age was associated with mortality (P = .0006). Myeloma-specific mortality was similar among cohorts at 12%, indicating an age-related effect on nonmyeloma mortality. Analyses were performed in a representative subgroup comparing relapse rate, progression-free survival (PFS), and nonrelapse mortality (NRM). One-year NRM was 0% for age >70 years and 2% for other ages (P = not significant). The three-year relapse rate was 56% in age 18 to 59 years, 61% in age 60 to 69 years, and 63% age >70 (P = not significant). Three-year PFS was similar at 42% in age 18 to 59 years, 38% in age 60 to 69 years, and 33% in age >70 years (P = not significant). Postrelapse survival was significantly worse for the older cohort (P = .03). Older subjects selected for AHCT derived similar antimyeloma benefit without worse NRM, relapse rate, or PFS. PMID:25046833

  16. New Experiments and a Model-Driven Approach for Interpreting Middle Stone Age Lithic Point Function Using the Edge Damage Distribution Method

    PubMed Central

    Schoville, Benjamin J.; Brown, Kyle S.; Harris, Jacob A.; Wilkins, Jayne

    2016-01-01

    The Middle Stone Age (MSA) is associated with early evidence for symbolic material culture and complex technological innovations. However, one of the most visible aspects of MSA technologies are unretouched triangular stone points that appear in the archaeological record as early as 500,000 years ago in Africa and persist throughout the MSA. How these tools were being used and discarded across a changing Pleistocene landscape can provide insight into how MSA populations prioritized technological and foraging decisions. Creating inferential links between experimental and archaeological tool use helps to establish prehistoric tool function, but is complicated by the overlaying of post-depositional damage onto behaviorally worn tools. Taphonomic damage patterning can provide insight into site formation history, but may preclude behavioral interpretations of tool function. Here, multiple experimental processes that form edge damage on unretouched lithic points from taphonomic and behavioral processes are presented. These provide experimental distributions of wear on tool edges from known processes that are then quantitatively compared to the archaeological patterning of stone point edge damage from three MSA lithic assemblages—Kathu Pan 1, Pinnacle Point Cave 13B, and Die Kelders Cave 1. By using a model-fitting approach, the results presented here provide evidence for variable MSA behavioral strategies of stone point utilization on the landscape consistent with armature tips at KP1, and cutting tools at PP13B and DK1, as well as damage contributions from post-depositional sources across assemblages. This study provides a method with which landscape-scale questions of early modern human tool-use and site-use can be addressed. PMID:27736886

  17. What Difference Reveals about Similarity

    ERIC Educational Resources Information Center

    Sagi, Eyal; Gentner, Dedre; Lovett, Andrew

    2012-01-01

    Detecting that two images are different is faster for highly dissimilar images than for highly similar images. Paradoxically, we showed that the reverse occurs when people are asked to describe "how" two images differ--that is, to state a difference between two images. Following structure-mapping theory, we propose that this disassociation arises…

  18. What causes similarity in catchments?

    NASA Astrophysics Data System (ADS)

    Savenije, Hubert

    2014-05-01

    One of the biggest issues in hydrology is how to handle the heterogeneity of catchment properties at different scales. But is this really such a big issue? Is this problem not merely the consequence of how we conceptualise and how we model catchments? Is there not far more similarity than we observe. Maybe we are not looking at the right things or at the right scale to see the similarity. The identity of catchments is largely determined by: the landscape, the ecosystem living on the landscape, and the geology, in that order. Soils, which are often seen as a crucial aspect of hydrological behaviour, are far less important, as will be demonstrated. The main determinants of hydrological behaviour are: the landscape composition, the rooting depth and the phenology. These determinants are a consequence of landscape and ecosystem evolution, which, in turn, are the manifestations of entropy production. There are striking similarities between catchments. The different runoff processes from hillslopes are linked and similar in different environments (McDonnell, 2013). Wetlands behave similarly all over the world. The key is to classify landscapes and to link the ecosystems living on them to climate. The ecosystem then is the main controller of hydrological behaviour. Besides phenology, the rooting depth is key in determining runoff behaviour. Both are strongly linked to climate and much less to soil properties. An example is given of how rooting depth is determined by climate, and how rooting depth can be predicted without calibration, providing a strong constraints on the prediction of rainfall partitioning and catchment runoff.

  19. Selection of USSR foreign similarity regions

    NASA Technical Reports Server (NTRS)

    Disler, J. M. (Principal Investigator)

    1982-01-01

    The similarity regions in the United States and Canada were selected to parallel the conditions that affect labeling and classification accuracies in the U.S.S.R. indicator regions. In addition to climate, a significant condition that affects labeling and classification accuracies in the U.S.S.R. is the proportion of barley and wheat grown in a given region (based on sown areas). The following regions in the United States and Canada were determined to be similar to the U.S.S.R. indicator regions: (1) Montana agrophysical unit (APU) 104 corresponds to the Belorussia high barley region; (2) North Dakota and Minnesota APU 20 and secondary region southern Manitoba and Saskatchewan correspond to the Ural RSFSR barley and spring wheat region; (3) Montana APU 23 corresponds to he North Caucasus barley and winter wheat region. Selection criteria included climates, crop type, crop distribution, growth cycles, field sizes, and field shapes.

  20. Active browsing using similarity pyramids

    NASA Astrophysics Data System (ADS)

    Chen, Jau-Yuen; Bouman, Charles A.; Dalton, John C.

    1998-12-01

    In this paper, we describe a new approach to managing large image databases, which we call active browsing. Active browsing integrates relevance feedback into the browsing environment, so that users can modify the database's organization to suit the desired task. Our method is based on a similarity pyramid data structure, which hierarchically organizes the database, so that it can be efficiently browsed. At coarse levels, the similarity pyramid allows users to view the database as large clusters of similar images. Alternatively, users can 'zoom into' finer levels to view individual images. We discuss relevance feedback for the browsing process, and argue that it is fundamentally different from relevance feedback for more traditional search-by-query tasks. We propose two fundamental operations for active browsing: pruning and reorganization. Both of these operations depend on a user-defined relevance set, which represents the image or set of images desired by the user. We present statistical methods for accurately pruning the database, and we propose a new 'worm hole' distance metric for reorganizing the database, so that members of the relevance set are grouped together.

  1. Does language about similarity play a role in fostering similarity comparison in children?

    PubMed Central

    Özçalışkan, Şeyda; Goldin-Meadow, Susan; Gentner, Dedre; Mylander, Carolyn

    2009-01-01

    Commenting on perceptual similarities between objects stands out as an important linguistic achievement, one that may pave the way towards noticing and commenting on more abstract relational commonalities between objects. To explore whether having a conventional linguistic system is necessary for children to comment on different types of similarity comparisons, we observed four children who had not been exposed to usable linguistic input—deaf children whose hearing losses prevented them from learning spoken language and whose hearing parents had not exposed them to sign language. These children developed gesture systems that have language-like structure at many different levels. Here we ask whether the deaf children used their gestures to comment on similarity relations and, if so, which types of relations they expressed. We found that all four deaf children were able to use their gestures to express similarity comparisons (POINT TO CAT+POINT TO TIGER) resembling those conveyed by 40 hearing children in early gesture+speech combinations (cat+POINT TO TIGER). However, the two groups diverged at later ages. Hearing children, after acquiring the word like, shifted from primarily expressing global similarity (as in cat/tiger) to primarily expressing single-property similarity (as in crayon is brown like my hair). In contrast, the deaf children, lacking an explicit term for similarity, continued to primarily express global similarity. The findings underscore the robustness of similarity comparisons in human communication, but also highlight the importance of conventional terms for comparison as likely contributors to routinely expressing more focused similarity relations. PMID:19524220

  2. Density-based similarity measures for content based search

    SciTech Connect

    Hush, Don R; Porter, Reid B; Ruggiero, Christy E

    2009-01-01

    We consider the query by multiple example problem where the goal is to identify database samples whose content is similar to a coUection of query samples. To assess the similarity we use a relative content density which quantifies the relative concentration of the query distribution to the database distribution. If the database distribution is a mixture of the query distribution and a background distribution then it can be shown that database samples whose relative content density is greater than a particular threshold {rho} are more likely to have been generated by the query distribution than the background distribution. We describe an algorithm for predicting samples with relative content density greater than {rho} that is computationally efficient and possesses strong performance guarantees. We also show empirical results for applications in computer network monitoring and image segmentation.

  3. Study of settlement distribution pattern in the Kolkheti lowland (Black Sea coast of Georgia) starting from early Bronze Age - natural and human influence and adaptation to landscape evolution

    NASA Astrophysics Data System (ADS)

    Elashvili, Mikheil; Akhvlediani, Dimitri; Navrozashvili, Levan; Sukhishvili, Lasha; Kirkitadze, Giorgi; Kelterbaum, Daniel; Laermans, Hannes

    2015-04-01

    archaeological datasets are collected in the joint-venture project and in addition with known historical and old topographic maps of the region they represent a good start for the research. There are typical ancient settlements in the Kolkheti lowland, called locally "Dikhagudzuba", which are still identifiable on aerial imagery. Their structure, physical dimensions and locations were analyzed from aerial and on site studies. Data from existing archaeological studies and recent field works were analyzed to create a reliable database on the distribution of Bronze Age settlements. Changes in paleoclimate, sea level and river deltas represent the main components to form a paleolandscape of the study area. Based on the results of recent fieldwork and the analyses of regional historical maps in addition with the general geological and geomorphological settings paleogeographical scenarios were constructed. Proposed models of past landscape changes and human settlement pattern were merged and analyzed. From one hand the human settlement distribution (taking into account tells relation with the local landscape of the same period) help us to identify the best suitable scenario from the set of paleolandscape patterns. Moreover, paleogeographical scenarios provide a better understanding on the erection of human settlements in the past, and their influence and adaptation to ongoing changes.

  4. Restructuring of Similarity Neighbourhoods in the Developing Mental Lexicon

    ERIC Educational Resources Information Center

    Storkel, Holly L.

    2002-01-01

    Previous evidence suggests that the structure of similarity neighbourhoods in the developing mental lexicon may differ from that of the fully developed lexicon. The similarity relationships used to organize words into neighbourhoods was investigated in 20 pre-school children (age 3;7 to 5;11) using a two alternative forced-choice classification…

  5. Mechanisms for similarity based cooperation

    NASA Astrophysics Data System (ADS)

    Traulsen, A.

    2008-06-01

    Cooperation based on similarity has been discussed since Richard Dawkins introduced the term “green beard” effect. In these models, individuals cooperate based on an aribtrary signal (or tag) such as the famous green beard. Here, two different models for such tag based cooperation are analysed. As neutral drift is important in both models, a finite population framework is applied. The first model, which we term “cooperative tags” considers a situation in which groups of cooperators are formed by some joint signal. Defectors adopting the signal and exploiting the group can lead to a breakdown of cooperation. In this case, conditions are derived under which the average abundance of the more cooperative strategy exceeds 50%. The second model considers a situation in which individuals start defecting towards others that are not similar to them. This situation is termed “defective tags”. It is shown that in this case, individuals using tags to cooperate exclusively with their own kind dominate over unconditional cooperators.

  6. Dyslexic and Skilled Reading Dynamics Are Self-Similar

    ERIC Educational Resources Information Center

    Holden, John G.; Greijn, Lieke T.; van Rooij, Marieke M. J. W.; Wijnants, Maarten L.; Bosman, Anna M. T.

    2014-01-01

    The shape of a word pronunciation time distribution supplies information about the dynamic interactions that support reading performance. Speeded word-naming pronunciation and response time distributions were collected from 20 sixth grade Dutch students with dyslexia and 23 age-matched controls. The participants' pronunciation times were…

  7. Terrestrial Kr-81-Kr ages of Antarctic meteorites

    NASA Technical Reports Server (NTRS)

    Freundel, M.; Schultz, L.; Reedy, R. C.

    1986-01-01

    The production rate of Ar-38 in meteorites P(38), has been determined, as a function of the sample's chemical composition, from Kr-81-Kr exposure ages of four eucrite falls. The cosmogenic Kr-78/Kr-83 ratio is used to estimate the shielding dependence of P(38). From the 'true' Ar-38 exposure ages and the apparent Kr-81-Kr exposure ages of nine Antarctic eucrite finds, terrestrial ages are calculated. They range from about 300,000 ages (Pecora Escarpment 82502) to very recent falls (Thiel Mountains 82502). Polymict eucrites from the Allan Hills (A78132, A79017, and A81009) have within the limits of error the same exposure age (15.2 x 10 to the 6th ages) and the same terrestrial age (110,000 ages). This is taken as strong evidence that these meteorites are fragments of the same fall. A similar case is the Elephant Moraine polymict eucrites A79005, A79006, and 82600 with an exposure age of 26 x 10 to the 6th ages and a terrestrial age of 180,000 ages. EETA 79004 may be different from this group because its exposure age and terrestrial age are 21 x 10 to the 6th ages and 250,000 ages, respectively. The distribution of terrestrial ages of Allan Hills meteorites is discussed. Meteorites from this blue ice field have two sources: directly deposited falls and meteorites transported to the Allen Hills inside the moving Antarctic ice sheet. During the surface residence time meteorites decompose due to weathering processes. The weathering 'half-life' is about 160,000 ages. From the different age distributions of Allan Hills and Yamato meteorites, it is concluded that meteorite concentrations of different Antarctic ice fields need different explanations.

  8. Path similarity skeleton graph matching.

    PubMed

    Bai, Xiang; Latecki, Longin Jan

    2008-07-01

    This paper presents a novel framework to for shape recognition based on object silhouettes. The main idea is to match skeleton graphs by comparing the shortest paths between skeleton endpoints. In contrast to typical tree or graph matching methods, we completely ignore the topological graph structure. Our approach is motivated by the fact that visually similar skeleton graphs may have completely different topological structures. The proposed comparison of shortest paths between endpoints of skeleton graphs yields correct matching results in such cases. The skeletons are pruned by contour partitioning with Discrete Curve Evolution, which implies that the endpoints of skeleton branches correspond to visual parts of the objects. The experimental results demonstrate that our method is able to produce correct results in the presence of articulations, stretching, and occlusion.

  9. Semantically enabled image similarity search

    NASA Astrophysics Data System (ADS)

    Casterline, May V.; Emerick, Timothy; Sadeghi, Kolia; Gosse, C. A.; Bartlett, Brent; Casey, Jason

    2015-05-01

    Georeferenced data of various modalities are increasingly available for intelligence and commercial use, however effectively exploiting these sources demands a unified data space capable of capturing the unique contribution of each input. This work presents a suite of software tools for representing geospatial vector data and overhead imagery in a shared high-dimension vector or embedding" space that supports fused learning and similarity search across dissimilar modalities. While the approach is suitable for fusing arbitrary input types, including free text, the present work exploits the obvious but computationally difficult relationship between GIS and overhead imagery. GIS is comprised of temporally-smoothed but information-limited content of a GIS, while overhead imagery provides an information-rich but temporally-limited perspective. This processing framework includes some important extensions of concepts in literature but, more critically, presents a means to accomplish them as a unified framework at scale on commodity cloud architectures.

  10. Self-similarity of complex networks.

    PubMed

    Song, Chaoming; Havlin, Shlomo; Makse, Hernán A

    2005-01-27

    Complex networks have been studied extensively owing to their relevance to many real systems such as the world-wide web, the Internet, energy landscapes and biological and social networks. A large number of real networks are referred to as 'scale-free' because they show a power-law distribution of the number of links per node. However, it is widely believed that complex networks are not invariant or self-similar under a length-scale transformation. This conclusion originates from the 'small-world' property of these networks, which implies that the number of nodes increases exponentially with the 'diameter' of the network, rather than the power-law relation expected for a self-similar structure. Here we analyse a variety of real complex networks and find that, on the contrary, they consist of self-repeating patterns on all length scales. This result is achieved by the application of a renormalization procedure that coarse-grains the system into boxes containing nodes within a given 'size'. We identify a power-law relation between the number of boxes needed to cover the network and the size of the box, defining a finite self-similar exponent. These fundamental properties help to explain the scale-free nature of complex networks and suggest a common self-organization dynamics.

  11. Final Report, The Influence of Organic-Aerosol Emissions and Aging on Regional and Global Aerosol Size Distributions and the CCN Number Budget

    SciTech Connect

    Donahue, Neil M.

    2015-12-23

    We conducted laboratory experiments and analyzed data on aging of organic aerosol and analysis of field data on volatility and CCN activity. With supplemental ASR funding we participated in the FLAME-IV campaign in Missoula MT in the Fall of 2012, deploying a two-chamber photochemical aging system to enable experimental exploration of photochemical aging of biomass burning emissions. Results from that campaign will lead to numerous publications, including demonstration of photochemical production of Brown Carbon (BrC) from secondary organic aerosol associated with biomass burning emissions as well as extensive characterization of the effect of photochemical aging on the overall concentrations of biomass burning organic aerosol. Excluding publications arising from the FLAME-IV campaign, project research resulted in 8 papers: [11, 5, 3, 10, 12, 4, 8, 7], including on in Nature Geoscience addressing the role of organic compounds in nanoparticle growth [11

  12. Social representations and normative beliefs of aging.

    PubMed

    Torres, Tatiana de Lucena; Camargo, Brigido Vizeu; Boulsfield, Andréa Barbará; Silva, Antônia Oliveira

    2015-12-01

    This study adopted the theory of social representations as a theoretical framework in order to characterize similarities and differences in social representations and normative beliefs of aging for different age groups. The 638 participants responded to self-administered questionnaire and were equally distributed by sex and age. The results show that aging is characterized by positive stereotypes (knowledge and experience); however, retirement is linked to aging, but in a negative way, particularly for men, involving illness, loneliness and disability. When age was considered, it was verified that the connections with the representational elements became more complex for older groups, showing social representation functionality, largely for the elderly. Adulthood seems to be preferred and old age is disliked. There were divergences related to the perception of the beginning of life phases, especially that of old age. Work was characterized as the opposite of aging, and it revealed the need for actions intended for the elderly and retired workers, with post-retirement projects. In addition, it suggests investment in public policies that encourage intergenerational contact, with efforts to reduce intolerance and discrimination based on age of people.

  13. Age-related impairment of visual recognition memory correlates with impaired synaptic distribution of GluA2 and protein kinase Mζ in the dentate gyrus.

    PubMed

    Aicardi, Giorgio

    2012-10-01

    Age-related functional alterations in the perforant path projection from the entorhinal cortex to the dentate gyrus (DG) of the hippocampus play a major role in age-related memory impairments, but little is known about the molecular mechanisms responsible for these changes. In a recent study, young and aged monkeys were tested on the visual recognition memory test "delayed nonmatching-to-sample"; then, electron microscopic immunocytochemistry was performed in the hippocampal DG to determine the subcellular localization of the GluA2 subunit of the glutamate α-amino-3-hydroxy-5-methyl-4- isoxazole-propionic acid receptor (AMPAR) and protein kinase Mζ (PKMζ), which promotes memory storage by regulating GluA2-containing AMPAR trafficking. The results obtained suggest that age-related deficits in visual recognition memory are coupled with impairment in PKMζ-dependent maintenance of GluA2 at the synapse. Together with previous evidences of the critical role of PKMζ in memory consolidation, these data render this enzyme an attractive potential therapeutic target for treating age-related memory decline, and support the view that the pharmacological manipulation of AMPAR trafficking in the synapses may provide new insights in the search of memory enhancers for aged individuals, including those affected by Alzheimer disease.

  14. Age-related impairment of visual recognition memory correlates with impaired synaptic distribution of GluA2 and protein kinase Mζ in the dentate gyrus.

    PubMed

    Aicardi, Giorgio

    2012-10-01

    Age-related functional alterations in the perforant path projection from the entorhinal cortex to the dentate gyrus (DG) of the hippocampus play a major role in age-related memory impairments, but little is known about the molecular mechanisms responsible for these changes. In a recent study, young and aged monkeys were tested on the visual recognition memory test "delayed nonmatching-to-sample"; then, electron microscopic immunocytochemistry was performed in the hippocampal DG to determine the subcellular localization of the GluA2 subunit of the glutamate α-amino-3-hydroxy-5-methyl-4- isoxazole-propionic acid receptor (AMPAR) and protein kinase Mζ (PKMζ), which promotes memory storage by regulating GluA2-containing AMPAR trafficking. The results obtained suggest that age-related deficits in visual recognition memory are coupled with impairment in PKMζ-dependent maintenance of GluA2 at the synapse. Together with previous evidences of the critical role of PKMζ in memory consolidation, these data render this enzyme an attractive potential therapeutic target for treating age-related memory decline, and support the view that the pharmacological manipulation of AMPAR trafficking in the synapses may provide new insights in the search of memory enhancers for aged individuals, including those affected by Alzheimer disease. PMID:22985047

  15. Aging & Health.

    PubMed

    2016-09-01

    By 2050 an estimated 83.7 million Americans will be ages sixty-five and older, up from 40.3 million in 2010. The shock wave of aging Americans will have profound implications for older people, their families, health care providers, and the economy. Researchers, policy makers, health care leaders, and others are designing responses to the challenges these actuarial shifts will create. For example, delivering health care at home could help keep more older Americans out of costly emergency departments and nursing homes. But such steps require more health care providers, a broader distribution of providers than currently exists, and better use of the resources we have. PMID:27605632

  16. Explosion Source Similarity Analysis via SVD

    NASA Astrophysics Data System (ADS)

    Yedlin, Matthew; Ben Horin, Yochai; Margrave, Gary

    2016-04-01

    An important seismological ingredient for establishing a regional seismic nuclear discriminant is the similarity analysis of a sequence of explosion sources. To investigate source similarity, we are fortunate to have access to a sequence of 1805 three-component recordings of quarry blasts, shot from March 2002 to January 2015. The centroid of these blasts has an estimated location 36.3E and 29.9N. All blasts were detonated by JPMC (Jordan Phosphate Mines Co.) All data were recorded at the Israeli NDC, HFRI, located at 30.03N and 35.03E. Data were first winnowed based on the distribution of maximum amplitudes in the neighborhood of the P-wave arrival. The winnowed data were then detrended using the algorithm of Cleveland et al (1990). The detrended data were bandpass filtered between .1 to 12 Hz using an eighth order Butterworth filter. Finally, data were sorted based on maximum trace amplitude. Two similarity analysis approaches were used. First, for each component, the entire suite of traces was decomposed into its eigenvector representation, by employing singular-valued decomposition (SVD). The data were then reconstructed using 10 percent of the singular values, with the resulting enhancement of the S-wave and surface wave arrivals. The results of this first method are then compared to the second analysis method based on the eigenface decomposition analysis of Turk and Pentland (1991). While both methods yield similar results in enhancement of data arrivals and reduction of data redundancy, more analysis is required to calibrate the recorded data to charge size, a quantity that was not available for the current study. References Cleveland, R. B., Cleveland, W. S., McRae, J. E., and Terpenning, I., Stl: A seasonal-trend decomposition procedure based on loess, Journal of Official Statistics, 6, No. 1, 3-73, 1990. Turk, M. and Pentland, A., Eigenfaces for recognition. Journal of cognitive neuroscience, 3(1), 71-86, 1991.

  17. Does similarity breed marital and sexual satisfaction?

    PubMed

    Zhang, Huiping; Ho, Petula S Y; Yip, Paul S F

    2012-01-01

    This study examined the effect of socioeconomic-cultural homogamy on the marital and sexual satisfaction of Hong Kong Chinese couples. Using a representative, territory-wide sample of 1,083 first-time married heterosexual couples, this study found that wives were generally less satisfied than their husbands with their marital and sexual relationships. Husbands were more likely to be satisfied with their marriages when they were two to four years older than their wives than when they were of similar age to their wives (i.e., within one year of each other), but they were less likely to be satisfied with their marriages when only their wives were employed than when both partners were employed. In addition, they were less likely to be satisfied with both their marital and sexual relationships when their wives were five or more years older. Wives with an older husband were more likely to be sexually satisfied than wives of the same age as their husband, but they were less likely to be satisfied with their marriages when they were better educated than their husbands. The implications of the findings are discussed.

  18. Does similarity breed marital and sexual satisfaction?

    PubMed

    Zhang, Huiping; Ho, Petula S Y; Yip, Paul S F

    2012-01-01

    This study examined the effect of socioeconomic-cultural homogamy on the marital and sexual satisfaction of Hong Kong Chinese couples. Using a representative, territory-wide sample of 1,083 first-time married heterosexual couples, this study found that wives were generally less satisfied than their husbands with their marital and sexual relationships. Husbands were more likely to be satisfied with their marriages when they were two to four years older than their wives than when they were of similar age to their wives (i.e., within one year of each other), but they were less likely to be satisfied with their marriages when only their wives were employed than when both partners were employed. In addition, they were less likely to be satisfied with both their marital and sexual relationships when their wives were five or more years older. Wives with an older husband were more likely to be sexually satisfied than wives of the same age as their husband, but they were less likely to be satisfied with their marriages when they were better educated than their husbands. The implications of the findings are discussed. PMID:21614722

  19. The economics of ageing: on the attitude of Swedish people to the distribution of health care resources between the young and the old.

    PubMed

    Johannesson, M; Johansson, P O

    1996-09-01

    The Swedish Priorities Investigation [1] proposes that no account should be taken of a patient's age when allocating health care resources. Measures to save an old person's life are to be given the same priority as measures to save a young person's life. In the present study it is shown that the attitude of the Swedish population to this age-related problem is dramatically different from that laid down in the priorities investigation. On average, people are willing to sacrifice thirty-five 70-year-olds to save one 30-year-old. It is also shown that a measure which increases life-expectancy by 1 year, conditional on having survived until the age of 75 years, is given a low weighting. The (maximum) insurance premium the average Swede is willing to pay for such a programme is about 700 pounds.

  20. Gestational age

    MedlinePlus

    Fetal age - gestational age; Gestation; Neonatal gestational age; Newborn gestational age ... Gestational age can be determined before or after birth. Before birth, your health care provider will use ultrasound to ...

  1. Similarities between protein folding and granular jamming

    PubMed Central

    Jose, Prasanth P; Andricioaei, Ioan

    2012-01-01

    Grains and glasses, widely different materials, arrest their motions upon decreasing temperature and external load, respectively, in common ways, leading to a universal jamming phase diagram conjecture. However, unified theories are lacking, mainly because of the disparate nature of the particle interactions. Here we demonstrate that folded proteins exhibit signatures common to both glassiness and jamming by using temperature- and force-unfolding molecular dynamics simulations. Upon folding, proteins develop a peak in the interatomic force distributions that falls on a universal curve with experimentally measured forces on jammed grains and droplets. Dynamical signatures are found as a dramatic slowdown of stress relaxation upon folding. Together with granular similarities, folding is tied not just to the jamming transition, but a more nuanced picture of anisotropy, preparation protocol and internal interactions emerges. Results have implications for designing stable polymers and can open avenues to link protein folding to jamming theory. PMID:23093180

  2. Spectral similarity of unbound asteroid pairs

    NASA Astrophysics Data System (ADS)

    Wolters, Stephen D.; Weissman, Paul R.; Christou, Apostolis; Duddy, Samuel R.; Lowry, Stephen C.

    2014-04-01

    Infrared (IR) spectroscopy between 0.8 and 2.5 μ has been obtained for both components of three unbound asteroid pairs, using the NASA Infrared Telescope Facility with the SpeX instrument. Pair primary (2110) Moore-Sitterly is classified as an S-type following the Bus-DeMeo taxonomy; the classification for secondary (44612) 1999 RP27 is ambiguous: S/Sq/Q/K/L-type. Primary (10484) Hecht and secondary (44645) 1999 RC118 are classified as V-types. IR spectra for Moore-Sitterly and Hecht are each linked with available visual photometry. The classifications for primary (88604) 2001 QH293 and (60546) 2000 EE85 are ambiguous: S/Sq/Q/K/L-type. Subtle spectral differences between them suggest that the primary may have more weathered material on its surface. Dynamical integrations have constrained the ages of formation: 2110-44612 > 782 kyr; 10484-44645 = 348 (+823,-225) kyr; 88604-60546 = 925 (+842,-754) kyr. The spectral similarity of seven complete pairs is ranked in comparison with nearby background asteroids. Two pairs, 17198-229056 and 19289-278067, have significantly different spectra between the components, compared to the similarity of spectra in the background population. The other pairs are closer than typical, supporting an interpretation of each pair's formation from a common parent body.

  3. Temporal-spatial distribution and tectonic implications of the batholiths in the Gaoligong-Tengliang-Yingjiang area, western Yunnan: Constraints from zircon U-Pb ages and Hf isotopes

    NASA Astrophysics Data System (ADS)

    Xu, Yi-Gang; Yang, Qi-Jun; Lan, Jiang-Bo;