Science.gov

Sample records for recession curve analysis

  1. Comparative analysis of base flow recession curves for different Andean catchments

    NASA Astrophysics Data System (ADS)

    Guzman, P.; Batelaan, O.; Wyseure, G.

    2012-04-01

    Little is known in the Paute River basin, Ecuador about the groundwater resources, the relation between aquifers and their recharge zones and interaction with rivers. The pressure from human activities in the river basin is increasing and impacting the surface water quality and quantity, therefore it becomes increasingly useful to estimate the potential of groundwater exploitation as an alternative resource. Due to the lack of specific groundwater data and information, assessment of suitable alternative methods for groundwater research at different scales is considered. In low flow hydrology literature it is noted that the majority of natural gains to streamflow during low-flow periods are derived from releases from groundwater storage, moreover baseflow is generally suggested to be an indicator of groundwater or other delayed sources. Analysis of flow recession curves allows the determination of characteristics of the groundwater reservoir, which is a prerequisite for the separation of baseflow from total discharge and the estimation of groundwater storage and recharge. The flow recession curve at a river cross section is defined as the discharge hydrograph of the basin during a rainless or dry period. Its analysis yields information on the retention characteristics of the basin and of groundwater storage and depletion. In the Paute River basin baseflows are assumed to be originating from Paramo storage, which is largely determined by the high water retention capacity of the soils in combination with their slopes. In the case of the sub-catchment of the Tarqui River, there are evidences based on topography, hydromorphology, discharges and soils that suggest the presence of a major aquifer in the valley. Hence, the goal of this contribution is the comparison and analysis of groundwater conditions based on baseflow recession analysis for the Tarqui and Yanuncay River sub-catchments. Baseflow analyses are translated in recharge and groundwater resources characteristics, as well as relationships with land cover, morphology, geology and rainfall are established and presented. The results are discussed within the framework of increasing pressures on the water system.

  2. Regionalization of subsurface stormflow parameters of hydrologic models: Derivation from regional analysis of streamflow recession curves

    SciTech Connect

    Ye, Sheng; Li, Hongyi; Huang, Maoyi; Ali, Melkamu; Leng, Guoyong; Leung, Lai-Yung R.; Wang, Shaowen; Sivapalan, Murugesu

    2014-07-21

    Subsurface stormflow is an important component of the rainfall–runoff response, especially in steep terrain. Its contribution to total runoff is, however, poorly represented in the current generation of land surface models. The lack of physical basis of these common parameterizations precludes a priori estimation of the stormflow (i.e. without calibration), which is a major drawback for prediction in ungauged basins, or for use in global land surface models. This paper is aimed at deriving regionalized parameterizations of the storage–discharge relationship relating to subsurface stormflow from a top–down empirical data analysis of streamflow recession curves extracted from 50 eastern United States catchments. Detailed regression analyses were performed between parameters of the empirical storage–discharge relationships and the controlling climate, soil and topographic characteristics. The regression analyses performed on empirical recession curves at catchment scale indicated that the coefficient of the power-law form storage–discharge relationship is closely related to the catchment hydrologic characteristics, which is consistent with the hydraulic theory derived mainly at the hillslope scale. As for the exponent, besides the role of field scale soil hydraulic properties as suggested by hydraulic theory, it is found to be more strongly affected by climate (aridity) at the catchment scale. At a fundamental level these results point to the need for more detailed exploration of the co-dependence of soil, vegetation and topography with climate.

  3. Geomorphological origin of recession curves

    NASA Astrophysics Data System (ADS)

    Biswal, Basudev; Marani, Marco

    2010-12-01

    We identify a previously undetected link between the river network morphology and key recession curves properties through a conceptual-physical model of the drainage process of the riparian unconfined aquifer. We show that the power-law exponent, ?, of -dQ/dt vs. Q curves is related to the power-law exponent of N(l) vs. G(l) curves (which we show to be connected to Hack's law), where l is the downstream distance from the channel heads, N(l) is the number of channel reaches exactly located at a distance l from their channel head, and G(l) is the total length of the network located at a distance greater or equal to l from channel heads. Using Digital Terrain Models and daily discharge observations from 67 US basins we find that geomorphologic ? estimates match well the values obtained from recession curves analyses. Finally, we argue that the link between recession flows and network morphology points to an important role of low-flow discharges in shaping the channel network.

  4. "Universal" Recession Curves and their Geomorphological Roots

    NASA Astrophysics Data System (ADS)

    Marani, M.; Biswal, B.

    2011-12-01

    The basic structural organization of channel networks, and of the connected hillslopes, have been shown to be intimately linked to basin responses to rainfall events, leading to geomorphological theories of the hydrologic response. Here, We identify a previously undetected link between the river network morphology and key recession curves properties. We show that the power-law exponent of -dQ/dt vs. Q curves is related to the power-law exponent of N(l) vs. G(l) curves (which we show to be connected to Hack's law), where l is the downstream distance from the channel heads, N(l) is the number of channel reaches exactly located at a distance l from their channel head, and G(l) is the total length of the network located at a distance greater or equal to l from channel heads. We then generalize the power-law expressions of recession curves, to identify "universal" curves, independent of the initial moisture conditions and of basin area, by making the -dQ/dt vs. Q curve non-dimensional using an index discharge representative of initial moisture conditions. We subsequently rescale the geomorphic recession curve, N(l) vs. G(l), producing a collapse of the geomorphic recession curves constructed from the DTM's of 67 US study basins. Finally, by use of the specific discharge u = Q/A, we link the two previous results and define the specific recession curves, whose collapse across basins within homogeneous geographical areas lends further, decisive, support to the notion that the statistical properties of observational recession curves bear the signature of the geomorphological structure of the networks producing them.

  5. An improved method for delineating source protection zones for karst springs based on analysis of recession curve data

    NASA Astrophysics Data System (ADS)

    Civita, Massimo V.

    2008-08-01

    A standard method for delineating source protection zones, particularly for karst and carbonate springs, has been improved. The method, based on recession curve analysis, defines four vulnerability scenarios with an evaluation of the appropriate dimensions of the protection areas, accommodating situations where field-test data are not available. The new approach makes it easier to separate the components of the spring discharge hydrograph. The objective is to achieve simplification, and an effective, more rigorous, procedure in the determination of the parameters used by Mangin’s model—Mangin A (1975) Contribution a l’étude hydrodynamique des aquifères karstiques-Troisieme partie: Constitution et fonctionnement des aquifères karstiques (Contribution to the hydrodynamic study of karst aquifers, part 3: formation and work of karst aquifers). Ann Speleol 30(1):21 124. The original procedure, plus the lack of sufficient data, was open to subjective interpretation. With the aid of modern technology, a very large quantity of data is now available and it is necessary to process it using denoise type computer-based filters before passing to interpretation. Working with discharge data series, a statistical approach is proposed to give an analytical solution for determining the values of fundamental parameters of the recession curve model. The new procedure is defined and compared with the original methodology. The new approach has been tested and applied to a number of karst springs in Italy. A case history for a spring located in the Piedmont region of the Maritime Alps, is presented. The proposed new procedure can be utilised to mark the limits of the protection zones of tapped groundwater supplied for potable use, as required by European and local legislation.

  6. Understanding Subsurface Flow Mechanisms by Studying Recession Flow Curves

    NASA Astrophysics Data System (ADS)

    patnaik, S.; Biswal, B.; D, N.

    2013-12-01

    The recession flows offer valuable information on the subsurface systems of the drainage which cannot be observed due to technological limitations. Many analytical frameworks have been proposed in the past to analyze recession flow curves assess. Among them the most widely used one is Brutsaert-Neiber method of expressing negative time derivative of Q (discharge at the basin outlet at time t), -dQ/dt, as a function of Q itself, which eliminates the need of finding a reference time. Typically, basins across geographical regions display a power law relationship of the type: -dQ/dt = kQ^α. For a particular basin, the exponent α remains fairly constant recession events while the coefficient k varies greatly from one recession event to another, indicating the dynamic nature -dQ/dt-Q relationship. Recent observations show that subsurface storage in a basin mainly controls the dynamic parameter k. As subsurface water takes long time to fully drain, k of a recession event can also be influenced by the storage that occurred during the past rainfall events. We indirectly analyze the effect of past storage on recession flow by considering past streamflow as a proxy of past storage. A stronger relationship implies that the basin is able to store water for longer duration, and vice versa. In this study, we used streamflow data from 388 USGS basins that are relatively unaffected by human activities to find out the factors that affect the relationship between the power law correlation (R^2_PN) between past discharge and k, where the subscript N is the number of days of past streamflow observations considered for the recession event. For most of the basins R^2_PN decreases with N. We then selected 18 physical and climatological parameters for each study basin and investigated how they influence the value of R^2_PN for each N. We followed multiple linear regression method and found that R^2_PN is strongly influenced by the selected parameters (R^2 = 0.58) for N =30 days. We also employed principal component analysis to identify influence of individual parameters on R^2_PN. Our findings strongly indicate the possibility of understanding subsurface flow mechanism by merely analyzing recession flow curves.

  7. Objective hydrograph baseflow recession analysis

    NASA Astrophysics Data System (ADS)

    Thomas, Brian F.; Vogel, Richard M.; Famiglietti, James S.

    2015-06-01

    A streamflow hydrograph recession curve expresses the theoretical relationship between aquifer structure and groundwater outflow to a stream channel. That theoretical relationship is often portrayed empirically using a recession plot defined as a plot of ln(-dQ/dt) versus ln(Q), where Q is streamflow discharge. Such hydrograph recession plots are commonly used to estimate recession parameters, aquifer properties and for evaluating alternative hydrologic hypotheses. We introduce a comprehensive and objective approach to analyze baseflow recessions with innovations including the use of quantile regression, efficient and objective numerical estimation of dQ/dt, inclusion of groundwater withdrawals, and incorporation of seasonal effects. We document that these innovations when all combined, lead to significant improvements, over previous studies, in our ability to discern the theoretical behavior of stream aquifer systems. A case study reveals that our methodology enables us to reject the simple linear reservoir hypothesis of stream aquifer interactions for watersheds in New Jersey and results in improved correlations between low flow statistics and aquifer properties for those same watersheds.

  8. Summer base-flow recession curves for Iowa streams

    USGS Publications Warehouse

    Saboe, C.W.

    1966-01-01

    Base-flow recession. curves for the summer months (June through September) were developed in this study for gaging stations on interior Iowa streams having five or more years of record. The tabulated data enables the user, starting with a known base flow at a gage, to estimate base flows for up to 20 days in the future. Rainfall during the period o£ the forecast will require that a new estimate be made after the stream again reaches base flow.

  9. Synthesis of streamflow recession curves in dry environments

    NASA Astrophysics Data System (ADS)

    Arciniega, Saul; Brea-Naranjo, Agustn; Pedrozo-Acua, Adran

    2015-04-01

    The elucidation and predictability of hydrological systems can largely benefit by extracting observed patterns in processes, data and models. Such type of research framework in hydrology, also known as synthesis has gained significant attention over the last decade. For instance, hydrological synthesis implies that the identification of patterns in catchment behavior can enhance the extrapolation of hydrological signatures over large spatial and temporal scales. Hydrological signatures during dry periods such as streamflow recession curves (SRC) are of special interest in regions coping with water scarcity. Indeed, the study of SRCs from observed hydrographs allows to extract information about the storage-discharge relationship of a specific catchment and some of their groundwater hydraulic properties. This work aims at performing a synthesis work of SRCs in semi-arid & arid environments across Northern Mexico. Our dataset consisted in observed daily SRCs in 63 catchments with minima human interferences. Three streamflow recession extraction methods (Vogel, Brutsaert and Aksoy-Wittenberg) along with four recession models (Maillet, Boussinesq, Coutagne y Wittenberg) and three parameter estimation techniques (regressions, lower envelope y data binning) were used to determine the combination among different possible methods, processes and models that better describes SRCs in our study sites. Our results show that the extraction method proposed by Aksoy-Wittenberg along with Coutagne's nonlinear recession model provides a better approximation of SRCs across Northern Mexico, whereas regression was found to be the most adequate parameter estimation method. This study suggests that hydrological synthesis turned out to be an useful framework to identify similar patterns and model parameters during dry periods across Mexico's water-limited environments.

  10. Effects of Antecedent Storage on Inter-Seasonal Recession Curve Variability

    NASA Astrophysics Data System (ADS)

    Bart, R. R.; Hope, A. S.

    2012-12-01

    Understanding the relation between streamflow recession rates and antecedent storage conditions is important for managing riparian ecosystems and forecasting low flows. This understanding is of particular interest in California watersheds where the climate regime is characterized by a large inter-seasonal contrast in precipitation that is out of phase with potential ET, leading to large differences in storage conditions between the beginning and the end of the winter wet season. The objective of this study was to investigate how streamflow recession rates in four watersheds located in the Santa Lucia Mountains of central California vary with antecedent streamflow, which was treated as an indicator of watershed storage conditions. Streamflow recession curves were grouped by antecedent streamflow and compared via examination of their recession slope curve on a log(-dQ/dt)-log(Q) plot. The results indicate that streamflow recession rates decrease with increasing antecedent streamflow. The relation between antecedent streamflow and recession rate follows a negative power law function, with a rapid decrease in recession rate following initial streamflow-producing events. This decrease is likely associated with a shift in the dominant source of recession flows from fast to slow stores as storage levels build up in slow parts of the watershed throughout the wet season. This paper concludes that evaluation of the effect inter-seasonal differences in storage conditions, not just evapotranspiration, is necessary for properly characterizing streamflow recession curves.

  11. Stream recession curves and storage variability in small watersheds

    NASA Astrophysics Data System (ADS)

    Krakauer, N. Y.; Temimi, M.

    2011-02-01

    The pattern of streamflow recession after rain events offers clues about the relationship between watershed runoff (observable as river discharge) and water storage (not directly observable) and can help in water resource assessment and prediction. However, it has not been systematically analyzed across flow rates or related to independent assessments of terrestrial water storage. We characterized the streamflow recession pattern in 61 relatively undisturbed small watersheds (1-100 km2) across the coterminous United States with multiyear records of hourly streamflow from automated gauges. We used the North American Regional Reanalysis (NARR) to help identify periods where precipitation, snowmelt, and evaporation were small compared to streamflow. The order of magnitude of the recession timescale increases from 1 day at high flow rates (~1 mm/h) to 10 days at low flow rates (~0.01 mm/h), leveling off at low flow rates. There is significant variability in the recession timescale at a given flow rate between basins, correlated with climate and geomorphic variables such as the ratio of mean streamflow to precipitation and soil water infiltration capacity. Stepwise multiple regression was used to construct a six-variable predictive model that explained some 80% of the variance in recession timescale at high flow rates and 30-50% at low flow rates. Seasonal and interannual variability in storage shows similar time evolution to but is up to a factor of 10 smaller than regional-scale water storage variability estimated from GRACE satellite gravity data and from land surface modeling forced by observed meteorology. The discrepancy may point to a "disconnection" between the conceptual pool that supplies streamflow during dry periods and other dynamic pools such as soil moisture and deep groundwater.

  12. Recession Curve Generation for the Space Shuttle Solid Rocket Booster Thermal Protection System Coatings

    NASA Technical Reports Server (NTRS)

    Kanner, Howard S.; Stuckey, C. Irvin; Davis, Darrell W.; Davis, Darrell (Technical Monitor)

    2002-01-01

    Ablatable Thermal Protection System (TPS) coatings are used on the Space Shuttle Vehicle Solid Rocket Boosters in order to protect the aluminum structure from experiencing excessive temperatures. The methodology used to characterize the recession of such materials is outlined. Details of the tests, including the facility, test articles and test article processing are also presented. The recession rates are collapsed into an empirical power-law relation. A design curve is defined using a 95-percentile student-t distribution. based on the nominal results. Actual test results are presented for the current acreage TPS material used.

  13. A computer program for predicting recharge with a master recession curve

    USGS Publications Warehouse

    Heppner, Christopher S.; Nimmo, John R.

    2005-01-01

    Water-table fluctuations occur in unconfined aquifers owing to ground-water recharge following precipitation and infiltration, and ground-water discharge to streams between storm events. Ground-water recharge can be estimated from well hydrograph data using the water-table fluctuation (WTF) principle, which states that recharge is equal to the product of the water-table rise and the specific yield of the subsurface porous medium. The water-table rise, however, must be expressed relative to the water level that would have occurred in the absence of recharge. This requires a means for estimating the recession pattern of the water-table at the site. For a given site there is often a characteristic relation between the water-table elevation and the water-table decline rate following a recharge event. A computer program was written which extracts the relation between decline rate and water-table elevation from well hydrograph data and uses it to construct a master recession curve (MRC). The MRC is a characteristic water-table recession hydrograph, representing the average behavior for a declining water-table at that site. The program then calculates recharge using the WTF method by comparing the measured well hydrograph with the hydrograph predicted by the MRC and multiplying the difference at each time step by the specific yield. This approach can be used to estimate recharge in a continuous fashion from long-term well records. Presented here is a description of the code including the WTF theory and instructions for running it to estimate recharge with continuous well hydrograph data.

  14. Recession analysis across scales: The impact of both random and nonrandom spatial variability on aggregated hydrologic response

    NASA Astrophysics Data System (ADS)

    Chen, Bo; Krajewski, Witold F.

    2015-04-01

    Recession analysis across scales can provide insight into the spatial aggregation of hydrologic processes. Accordingly, we analyzed individual late-time recession curves from 25 nested USGS stream gauges over a period of ∼150 days with negligible precipitation during the 2012-2013 North American drought. These gauges are located in the Iowa and Cedar River basins and drain areas ranging from ∼70 to 17,000 km2. Our data analyses show that these late-time recession processes can be represented by a linear reservoir model with a constant recession time scale of about 34 days, indicating linear and homogeneous recession behaviors at the large scales investigated. However, others have shown that the early-time recession process becomes more nonlinear as spatial scale and, thus, spatial variability increases. We developed a distributed drainage model as a diagnostic tool to understand these seemingly contradictory recession characteristics at multiple spatial scales and different stages. With a hierarchical description of the recession variability at the hillslope scale, our model can simultaneously produce the increasing nonlinear early-time and the linear and homogenous late-time recession behaviors at larger scales. The hierarchical representation classifies hillslopes according to the Strahler orders of the stream links into which they drain. We postulate that a larger difference in recession behaviors will occur between hillslopes from different orders than between those from the same order. Overall, this study shows how the spatial randomness and nonrandomness of small-scale process variability control the hydrologic responses at larger scales and suggests a combined (nonrandom-random) representation of watersheds for aggregating hydrologic processes.

  15. Peak flow rate and recession-curve characteristics of a karst spring in the Inner Bluegrass, central Kentucky

    USGS Publications Warehouse

    Felton, G.K.; Currens, J.C.

    1994-01-01

    The flow rate at the terminal spring of a 1929 ha karst ground-water catchment has been continuously monitored for 2 years, and 108 identifiable events were analyzed. The peak flow rates followed a beta frequency distribution with parameters ?? = 0.365 and ?? = 1.135. Events were separated into high-flow and low-flow. High-flow events had characteristics attributable to pipe flow. Correlation and stepwise regression were used to develop peak flow rate prediction equations for the combined 108 events and for the 81 low-flow events. The portion of the recession curve identified as pipe flow was a watershed constant and time invariant. The base flow was seasonal, increasing in the winter to approximately 0.071 m3s-1 and decreasing in the summer to approximately 0.014 m3s-1. ?? 1994.

  16. Analysis of Exoplanet Light Curves

    NASA Astrophysics Data System (ADS)

    Erdem, A.; Budding, E.; Rhodes, M. D.; Püsküllü, Ç.; Soydugan, F.; Soydugan, E.; Tüysüz, M.; Demircan, O.

    2015-07-01

    We have applied the close binary system analysis package WINFITTER to a variety of exoplanet transiting light curves taken both from the NASA Exoplanet Archive and our own ground-based observations. WINFitter has parameter options for a realistic physical model, including gravity brightening and structural parameters derived from Kopal's applications of the relevant Radau equation, and it includes appropriate tests for determinacy and adequacy of its best fitting parameter sets. We discuss a number of issues related to empirical checking of models for stellar limb darkening, surface maculation, Doppler beaming, microvariability, and transit time variation (TTV) effects. The Radau coefficients used in the light curve modeling, in principle, allow structural models of the component stars to be tested.

  17. Social Skills Intervention during Elementary School Recess: A Visual Analysis.

    ERIC Educational Resources Information Center

    Anderson-Butcher, Dawn; Newsome, W. Sean; Nay, Stephanie

    2003-01-01

    This study builds on two studies that explored the effect of a social skills intervention on problem behaviors displayed by elementary school children during recess. Findings conclude that social skills intervention significantly decreased problem behaviors among school children at recess. Implications for behavioral management and healthy school…

  18. Estimating parental relationship in linkage analysis of recessive traits

    SciTech Connect

    Merette, C.; Ott, J.

    1996-05-17

    In linkage analysis of recessive traits, parental relationship is important. For the case that it is unknown, the question is investigated as to whether estimating parental relationship and using the estimated relationship in linkage analysis is beneficial. Results show that estimating parental relationship can reliably be carried out on the basis of 50-100 genetic marker loci (analysis based on theory by Thompson). Misspecification of parental relationship leads to a loss of linkage informativeness, but not to false-positive evidence for linkage. An asymptotic bias in the recombination fraction estimate occurs when parents are unrelated and falsely taken to be related, but no such bias is seen when related parents are taken to be unrelated. Results from this investigation suggest that an estimated parental relationship may be used in linkage analysis as if it were the correct relationship, when evidence for the estimated relationship is supported by a likelihood ratio of at least 10:1 against the parents being unrelated. 9 refs., 2 figs., 5 tabs.

  19. Recession analysis of the Hupselse Beek catchment, The Netherlands

    NASA Astrophysics Data System (ADS)

    Brauer, C. C.; Stricker, J. N. M.; Warmerdam, P. M. M.; Uijlenhoet, R.

    2009-04-01

    Many parametric hydrological models use one or more linear reservoirs as model components. However, linear reservoirs may not be ideal to represent the real, nonlinear hydrologic behavior of a catchment. The reservoir coefficients of catchments can be obtained from discharge data with a method suggested by Brutsaert and Nieber (1977). From dry weather recession curves in hydrographs, the negative of the discharge changes over time were extracted and plotted against the discharge in a double logarithmic graph. The slope of the lower envelope around the separate points corresponds with the exponent of the reservoir (one for linear reservoirs). Kirchner (in press) adapted this method and fitted a regression line through the means of the points to determine reservoir coefficients for the Plynlimon catchment. The obtained reservoir coefficients were implemented in a simple model based on an integration of the nonlinear storage - discharge relation to reconstruct the streamflow hydrograph In this research project Kirchner's method is used to determine the reservoir coefficients and run the model for the Hupselse Beek catchment in the Netherlands. Hourly discharge, precipitation and evapotranspiration data for the period May 1979 - March 1987 have been used for this purpose. Compared to the Plynlimon catchment, our study catchment is much less humid and soil physical processes such as capillary rise play a more important role. The results show that the reservoir exponent is larger than one, which implies that the behavior of the catchment is nonlinear. The reservoir coefficients obtained for summer periods differ from those obtained for winter periods. Another result is that streamflow in the Hupselse Beek catchment cannot be reconstructed completely with the simple model described above. Winter discharges can often be modeled quite well, but the model fails in simulating summer periods or dry spells. When evapotranspiration rates exceed modeled storage volume plus precipitation, negative discharges are produced and the model collapses. A quick fix could be to introduce a fixed lower limit to avoid negative discharges. However, it does not yield satisfactory results either. This suggests that additional hydrological processes (eg. a soil moisture reservoir and capillary rise) should be included in the parameterization in order to obtain plausible model results for the study catchment. Brutsaert, W. and J. L. Nieber, Regionalized drought flow hydrographs from a mature glaciated plateau, Water Resources Research, 13, 637-643, 1977 Kirchner, J.W., Catchments as simple dynamical systems: catchment characterization, rainfall-runoff modeling, and doing hydrology backwards, Water Resources Research, in press

  20. Performance analysis of SOI MOSFET with rectangular recessed channel

    NASA Astrophysics Data System (ADS)

    Singh, M.; Mishra, S.; Mohanty, S. S.; Mishra, G. P.

    2016-03-01

    In this paper a two dimensional (2D) rectangular recessed channel-silicon on insulator metal oxide semiconductor field effect transistor (RRC-SOI MOSFET), using the concept of groove between source and drain regions, which is one of the channel engineering technique to suppress the short channel effect (SCE). This suppression is mainly due to corner potential barrier of the groove and the simulation is carried out by using ATLAS 2D device simulator. To have further improvement of SCE in RRC-SOI MOSFET, three more devices are designed by using dual material gate (DMG) and gate dielectric technique, which results in formation of devices i.e. DMRRC-SOI,MLSMRRC-SOI, MLDMRRC-SOI MOSFET. The effect of different structures of RRC-SOI on AC and RF parameters are investigated and the importance of these devices over RRC MOSFET regarding short channel effect is analyzed.

  1. Peranso - Light curve and period analysis software

    NASA Astrophysics Data System (ADS)

    Paunzen, E.; Vanmunster, T.

    2016-02-01

    A time series is a sample of observations of well-defined data points obtained through repeated measurements over a certain time range. The analysis of such data samples has become increasingly important not only in natural science but also in many other fields of research. Peranso offers a complete set of powerful light curve and period analysis functions to work with large astronomical data sets. Substantial attention has been given to ease-of-use and data accuracy, making it one of the most productive time series analysis software available. In this paper, we give an introduction to Peranso and its functionality.

  2. Analysis of light curve of LP Camelopardalis

    NASA Astrophysics Data System (ADS)

    Prudil, Z.; Skarka, M.; Zejda, M.

    2016-05-01

    We present photometric analysis of the RRab type pulsating star LP Cam. The star was observed at Brno Observatory and Planetarium during nine nights. Measurements were calibrated to the Johnson photometric system. Four captured and thirteen previously published maxima timings allowed us to refine the pulsation period and the zero epoch. The light curve was Fourier decomposed to estimate physical parameters using empirical relations. Our results suggest that LP Cam is a common RR Lyrae star with high, almost solar metallicity.

  3. Incorporating Experience Curves in Appliance Standards Analysis

    SciTech Connect

    Garbesi, Karina; Chan, Peter; Greenblatt, Jeffery; Kantner, Colleen; Lekov, Alex; Meyers, Stephen; Rosenquist, Gregory; Buskirk, Robert Van; Yang, Hung-Chia; Desroches, Louis-Benoit

    2011-10-31

    The technical analyses in support of U.S. energy conservation standards for residential appliances and commercial equipment have typically assumed that manufacturing costs and retail prices remain constant during the projected 30-year analysis period. There is, however, considerable evidence that this assumption does not reflect real market prices. Costs and prices generally fall in relation to cumulative production, a phenomenon known as experience and modeled by a fairly robust empirical experience curve. Using price data from the Bureau of Labor Statistics, and shipment data obtained as part of the standards analysis process, we present U.S. experience curves for room air conditioners, clothes dryers, central air conditioners, furnaces, and refrigerators and freezers. These allow us to develop more representative appliance price projections than the assumption-based approach of constant prices. These experience curves were incorporated into recent energy conservation standards for these products. The impact on the national modeling can be significant, often increasing the net present value of potential standard levels in the analysis. In some cases a previously cost-negative potential standard level demonstrates a benefit when incorporating experience. These results imply that past energy conservation standards analyses may have undervalued the economic benefits of potential standard levels.

  4. Light-curve Analysis of Neon Novae

    NASA Astrophysics Data System (ADS)

    Hachisu, Izumi; Kato, Mariko

    2016-01-01

    We analyzed light curves of five neon novae, QU Vul, V351 Pup, V382 Vel, V693 CrA, and V1974 Cyg, and determined their white dwarf (WD) masses and distance moduli on the basis of theoretical light curves composed of free-free and photospheric emission. For QU Vul, we obtained a distance of d ˜ 2.4 kpc, reddening of E(B - V) ˜ 0.55, and WD mass of MWD = 0.82-0.96 {M}⊙ . This suggests that an oxygen-neon WD lost a mass of more than ˜ 0.1 {M}⊙ since its birth. For V351 Pup, we obtained d˜ 5.5 {{kpc}}, E(B-V)˜ 0.45, and {M}{{WD}}=0.98-1.1 {M}⊙ . For V382 Vel, we obtained d˜ 1.6 {{kpc}}, E(B-V)˜ 0.15, and {M}{{WD}}=1.13-1.28 {M}⊙ . For V693 CrA, we obtained d˜ 7.1 {{kpc}}, E(B-V)˜ 0.05, and {M}{{WD}}=1.15-1.25 {M}⊙ . For V1974 Cyg, we obtained d˜ 1.8 {{kpc}}, E(B-V)˜ 0.30, and {M}{{WD}}=0.95-1.1 {M}⊙ . For comparison, we added the carbon-oxygen nova V1668 Cyg to our analysis and obtained d˜ 5.4 {{kpc}}, E(B-V)˜ 0.30, and {M}{{WD}}=0.98-1.1 {M}⊙ . In QU Vul, photospheric emission contributes 0.4-0.8 mag at most to the optical light curve compared with free-free emission only. In V351 Pup and V1974 Cyg, photospheric emission contributes very little (0.2-0.4 mag at most) to the optical light curve. In V382 Vel and V693 CrA, free-free emission dominates the continuum spectra, and photospheric emission does not contribute to the optical magnitudes. We also discuss the maximum magnitude versus rate of decline relation for these novae based on the universal decline law.

  5. What Is a Recessive Allele?

    ERIC Educational Resources Information Center

    American Biology Teacher, 1991

    1991-01-01

    Presents four misconceptions students have concerning the concepts of recessive and dominant alleles. Discusses the spectrum of dominant-recessive relationships, different levels of analysis between phenotype and genotype, possible causes of dominance, and an example involving wrinkled peas. (MDH)

  6. The Informative Analysis of Individual Trend Curves

    ERIC Educational Resources Information Center

    McDonald, Roderick P.

    2004-01-01

    Additive and non-additive models for an individual trend curve are examined, and five methods for fitting these to a set of individuals are described. It is suggested that classical fitting methods are more informative than latent curve methods, and commonly preferable. A limited study of the effect of time-structure is reported, and results on…

  7. Estimation of baseflow and water transfer in karst catchments in Mediterranean Turkey by nonlinear recession analysis

    NASA Astrophysics Data System (ADS)

    Eris, Ebru; Wittenberg, Hartmut

    2015-11-01

    Because of water transfers through fissures, cavities, caves and phreatic channels of various sizes and unknown directions, the topographic watersheds of karst catchments have little significance for their aquifers. Most of the flow in the Manavgat River in South Anatolia has its origin outside of the surface watershed and is transferred through karst pathways. Previous investigations found evidence for this by groundwater tracing techniques. In this study, flow recession analysis and baseflow separation are applied to the time series of daily flows 1992-2008 from three gauging stations. Flow recessions were found corresponding to the nonlinear storage-baseflow relationship S = a·Qb, with b values around 0.5 as typical for unconfined groundwater, while the coefficient a showed marked seasonal variations with higher values in the rainy winter time and decreasing values towards the dry summer. For catchments which receive water transfers from other areas, the decrease of a is retarded. Flow recession is slower since more water is available. Baseflow separation by using the same nonlinear model revealed that direct flow, which is mainly surface flow, corresponds roughly to the surface catchments while baseflow, which accounts for most of the total flow, is highly influenced by transfers from karst sink areas outside the surface watersheds. The subsurface transfer was simulated by a nonlinear reservoir routing algorithm. Time series of monthly baseflow from catchments which receive transfer water were compared with those of sinkhole (loss) areas. The procedure allows inferring the origin area of the inflows and estimating the retention or lag time of the transfer.

  8. Replication and Analysis of Ebbinghaus’ Forgetting Curve

    PubMed Central

    Murre, Jaap M. J.; Dros, Joeri

    2015-01-01

    We present a successful replication of Ebbinghaus’ classic forgetting curve from 1880 based on the method of savings. One subject spent 70 hours learning lists and relearning them after 20 min, 1 hour, 9 hours, 1 day, 2 days, or 31 days. The results are similar to Ebbinghaus' original data. We analyze the effects of serial position on forgetting and investigate what mathematical equations present a good fit to the Ebbinghaus forgetting curve and its replications. We conclude that the Ebbinghaus forgetting curve has indeed been replicated and that it is not completely smooth but most probably shows a jump upwards starting at the 24 hour data point. PMID:26148023

  9. Autosomal recessive

    MedlinePlus

    ... and the other gene comes from the father. Recessive inheritance means both genes in a pair must be abnormal to cause ... born to parents who carry the same autosomal recessive change ... abnormal gene from both parents and developing the disease. You ...

  10. Rapid multipoint linkage analysis of recessive traits in nuclear families, including homozygosity mapping

    SciTech Connect

    Kruglyak, L.; Daly, M.J.; Lander, E.S. |

    1995-02-01

    Homozygosity mapping is a powerful strategy for mapping rare recessive traits in children of consanguineous marriages. Practical applications of this strategy are currently limited by the inability of conventional linkage analysis software to compute, in reasonable time, multipoint LOD scores for pedigrees with inbreeding loops. We have developed a new algorithm for rapid multipoint likelihood calculations in small pedigrees, including those with inbreeding loops. The running time of the algorithm grows, at most, linearly with the number of loci considered simultaneously. The running time is not sensitive to the presence of inbreeding loops, missing genotype information, and highly polymorphic loci. We have incorporated this algorithm into a software package, MAPMAKER/HOMOZ, that allows very rapid multipoint mapping of disease genes in nuclear families, including homozygosity mapping. Multipoint analysis with dozens of markers can be carried out in minutes on a personal workstation. 23 refs., 4 figs., 1 tab.

  11. SS433 Trek 2: light curve analysis.

    NASA Astrophysics Data System (ADS)

    Fukue, J.; Obana, Y.; Okugami, M.

    The authors have calculated theoretical light curves of SS433 during eclipse and precession, using a model in which SS433 consists of a geometrically thick torus around a compact star and a companion star filling the Roche lobe. The favorite combination is that the mass ratio is about 2 (a compact star is a black hole) and the surface temperature of the companion is around 17000K.

  12. Molecular and phenotypic analysis of 25 recessive, homozygous-viable alleles at the mouse agouti locus.

    PubMed Central

    Miltenberger, Rosalynn J; Wakamatsu, Kazumasa; Ito, Shosuke; Woychik, Richard P; Russell, Liane B; Michaud, Edward J

    2002-01-01

    Agouti is a paracrine-acting, transient antagonist of melanocortin 1 receptors that specifies the subapical band of yellow on otherwise black hairs of the wild-type coat. To better understand both agouti structure/function and the germline damage caused by chemicals and radiation, an allelic series of 25 recessive, homozygous-viable agouti mutations generated in specific-locus tests were characterized. Visual inspection of fur, augmented by quantifiable chemical analysis of hair melanins, suggested four phenotypic categories (mild, moderate, umbrous-like, severe) for the 18 hypomorphs and a single category for the 7 amorphs (null). Molecular analysis indicated protein-coding alterations in 8 hypomorphs and 6 amorphs, with mild-moderate phenotypes correlating with signal peptide or basic domain mutations, and more devastating phenotypes resulting from C-terminal lesions. Ten hypomorphs and one null demonstrated wild-type coding potential, suggesting that they contain mutations elsewhere in the > or = 125-kb agouti locus that either reduce the level or alter the temporal/spatial distribution of agouti transcripts. Beyond the notable contributions to the field of mouse germ cell mutagenesis, analysis of this allelic series illustrates that complete abrogation of agouti function in vivo occurs most often through protein-coding lesions, whereas partial loss of function occurs slightly more frequently at the level of gene expression control. PMID:11861569

  13. Decline curve derivative analysis for homogeneous and composite reservoirs

    SciTech Connect

    Demski, J.A.

    1987-06-01

    In this study, the rate decline and rate decline derivatives of a constant pressure well are presented for infinite, constant pressure outer boundary, and closed outer boundary homogeneous reservoirs. A rate derivative type curve is provided for these cases as well. The effects of the dimensionless reservoir exterior radius are discussed. Rate decline and rate decline derivatives of a constant pressure well in an infinite composite reservoir are also presented. For composite reservoirs, the effects of mobility ratios and discontinuity distance on both rate decline and rate decline derivatives are presented. Type curves for dimensionless wellbore flow rate derivatives for infinite composite reservoirs are provided. A new correlating group for the derivative type curve is provided, and is different than the correlating group for the rate type curve presented in the past. Finally, an analysis method that comprises type curve and derivative type curve matching to determine the dimensionless variables is proposed and demonstrated with a simulated example.

  14. Shape Analysis of Elastic Curves in Euclidean Spaces.

    PubMed

    Srivastava, Anuj; Klassen, Eric; Joshi, Shantanu H; Jermyn, Ian H

    2011-07-01

    This paper introduces a square-root velocity (SRV) representation for analyzing shapes of curves in euclidean spaces under an elastic metric. In this SRV representation, the elastic metric simplifies to the IL(2) metric, the reparameterization group acts by isometries, and the space of unit length curves becomes the unit sphere. The shape space of closed curves is the quotient space of (a submanifold of) the unit sphere, modulo rotation, and reparameterization groups, and we find geodesics in that space using a path straightening approach. These geodesics and geodesic distances provide a framework for optimally matching, deforming, and comparing shapes. These ideas are demonstrated using: 1) shape analysis of cylindrical helices for studying protein structure, 2) shape analysis of facial curves for recognizing faces, 3) a wrapped probability distribution for capturing shapes of planar closed curves, and 4) parallel transport of deformations for predicting shapes from novel poses. PMID:20921581

  15. Evaluating knickpoint recession along an active fault for paleoseismological analysis: The Huoshan Piedmont, Eastern China

    NASA Astrophysics Data System (ADS)

    Wei, Zhanyu; Bi, Lisi; Xu, Yueren; He, Honglin

    2015-04-01

    Ground-rupturing earthquakes can generate tectonic knickpoints within upstream reaches of streams across active fault zones. These knickpoints are characteristic of upstream propagation of time-related process once generated by an earthquake, so analysis of knickpoint series in streams which cross fault zones can be used to infer paleoearthquake events. We studied the knickpoints along the Huoshan Piedmont Fault (HPF), which is an active normal fault in the Shanxi Faulted Basin zone, China, and demonstrate that analysis of knickpoints shows evidence for two paleoearthquakes in the HPF. First, we identified knickpoints in bedrock reaches upstream of the HPF using high-resolution DEMs derived from IRS-P5 stereo images and the stream-gradient method. After excluding non-faulting knickpoints, 47 knickpoints were identified in 23 bedrock reaches upstream from the HPF. Analysis of the most recent knickpoints caused by the 1303 CE Hongdong Earthquake allowed for local calibration of the retreat rates. Applying these retreat rates across the study area allows for the estimation of the age of other knickpoints, and constrains the age ranges of two knickpoint groups to be 2269-3336 a BP and 4504-5618 a BP. These ages constrain the ages of two paleoearthquake events at 2710 102 and 4980 646 a BP. The knickpoints along the HPF obey the parallel retreating model in which knickpoint morphology was roughly maintained during retreat, so the heights of knickpoints represent the coseismic vertical displacements generated by the earthquakes along the HPF. The vertical offsets for these three earthquake events are similar and are approximately 4 m, which indicates that the ruptures on the HPF obey a characteristic slip model with a similar slip distribution for several successive earthquakes. These results provide additional evidence of paleoearthquakes on the HPF and show that analysis of knickpoint recession along an active fault is a valuable tool for paleoseismology.

  16. Applied Budyko curve analysis for county level water resources management

    NASA Astrophysics Data System (ADS)

    Yang, Y. E.; Lin, Y. F.

    2010-12-01

    Human population growth and urbanization exert significant controls on the water and energy balance of many watersheds. The framework of Budyko curve analysis provides a systematic approach to distinguish the local human influences such as surface water regulation, groundwater pumping and land cover change from global climate variation in such watersheds. Two indices, Budyko curve distance (?BC, the distance between a-ratios to the origin on the Budyko diagram) and Budyko curve deviation (?BC, the distance between a-ratios to the original Budyko curve on the Budyko diagram), are computed from the Budyko curve for McHenry County, Illinois (USA), and we test the hypothesis that these indices represent the impact of climate variation and human influences, respectively. Spatial and temporal analysis of the Budyko curve demonstrates that the dominant land cover within a watershed affects the shape and position of the Budyko curve and, therefore, the slope and intercept of the logarithmic regression function defining the curve (i.e., the water and energy characteristics of the watershed). Correlations between per capita water use and ?BC and between farm proprietors income and ?BC may explain how climate and human control factors affect these socioeconomic phenomena. Further studies are required to reduce the uncertainties of these correlations.

  17. Genetic analysis of loci that contribute to recessive polycystic kidney disease in the mouse

    SciTech Connect

    Beier, D.R.; Dushkin, H.; Tobin, D.

    1994-09-01

    Identification of genes that play a role in the development of autosomal recessive polycystic kidney disease (ARPKD) is a key to the better understanding of this disorder. We have discovered a new mutation in the mouse we call juvenile cystic kidney (jck) which predisposes to the development of ARPKD and is not allelic with any previously described mutations. In an effort to map and positionally clone the jck gene, an intraspecific intercross between B6/DBA jck/+F1 mice was established and over 100 affected progeny were identified. Genotype analysis using microsatellite markers was employed and the jck mutation has been mapped to a 1 cM interval on mouse chromosome 11. Positional cloning of this mutant locus by employing a YAC contig is in progress. Narrowing the region of interest has been facilitated by the utilization of SSCP analysis to develop informative markers from YAC sequence. In addition, it was noted that severity of disease in the intercross progeny (as measured by the degree of kidney enlargement) was more variable than that observed in the parental B6 strain. This suggested that a modifier locus introduced form the DBA background affects the expression of the jck phenotype. We have determined that two additional regions - one from DBA on distal chromosome 10 and a second from B6 on chromosome 1 - are strongly associated with inheritance of a more severe polycystic kidney disease phenotype. The finding of a highly significant association of a B6-related locus with kidney enlargement was completely unexpected, since the PKD phenotype in the original B6 background is not severe. This finding is unambiguous, with a maximal quantitative trait locus (QTL) analysis LOD score of 15 for association with disease severity. We propose that it is the inheritance of both a homozygous B6 locus on chromosome 1 and a DBA gene that results in the severe phenotype, presumably as a consequence of an interaction between their protein products.

  18. Recession Vs Myotomy–Comparative Analysis of Two Surgical Procedures of Weakening Inferior Oblique Muscle Overaction

    PubMed Central

    Alajbegovic-Halimic, Jasmina; Zvizdic, Denisa; Sahbegovic-Holcner, Amra; Kulanic-Kuduzovic, Amira

    2015-01-01

    Introduction: Inferior oblique overaction (IOOA) can be primary or secondary, isolated or combined to other types of horizontal deviation, mostly with esotropias. Surgical weakening of IOOA means several techniques like; recession, myotomy, myectomy, anteroposition etc. Goals: we analyzed the effect of inferior oblique muscle surgical weakening comparing two groups of patients with primary hypertropia. Material and methods: In 5-years retrospective study, we observed 33 patients on which we did the surgical procedure of weakening inferior muscle overaction by two methods; recession and myotomy. Results: In total number of 33 patients, there were 57,6% male and 42,4% female patients with average age of 10,6±7,5 (in range of 4–36). There was 33,3% of isolated primary hypertropias, and 66,7% combined with esotropias. At 23 (69,9%) patients the recession surgical procedure was done, and with 10 (30,1%) myotomy. Better effect and binocularity was in 65,2% of patients in recession group which was statistically significant with significance level of p<0,0, χ2=5,705; p=0,021. Conclusion: Comparing of two surgical procedures of weakening inferior oblique muscles overaction, recession is better procedure than myotomy. PMID:26261384

  19. Band analysis by spectral curve fitting

    NASA Technical Reports Server (NTRS)

    Lin, C. L.; Shaw, J. H.; Calvert, J. G.

    1980-01-01

    A method of estimating the values of the parameters in the models describing the positions, widths, and intensities of the lines in rotation-vibration bands of gases, without the need for line by line analysis, is described. To illustrate the technique, portions of the 1-0 bands of HCl and CO have been analyzed. The values of up to 27 parameters, their standard deviations, and the correlations between the parameters required to describe the spectra have been obtained.

  20. Comparative Transcriptome Analysis of Recessive Male Sterility (RGMS) in Sterile and Fertile Brassica napus Lines

    PubMed Central

    Zhao, Huiyan; Liu, Chuan; Li, Jiana; Tang, Zhanglin; Xu, Xinfu; Qiu, Xiao; Wang, Rui; Lu, Kun

    2015-01-01

    The recessive genetic male sterility (RGMS) system plays a key role in the production of hybrid varieties in self-pollinating B. napus plants, and prevents negative cytoplasmic effects. However, the complete molecular mechanism of the male sterility during male-gametogenesis in RGMS remains to be determined. To identify transcriptomic changes that occur during the transition to male sterility in RGMS, we examined the male sterile line WSLA and male fertile line WSLB, which are near-isogenic lines (NILs) differing only in the fertility trait. We evaluated the phenotypic features and sterility stage using anatomical analysis. Comparative RNA sequencing analysis revealed that 3,199 genes were differentially expressed between WSLA and WSLB. Many of these genes are mainly involved in biological processes related to flowering, including pollen tube development and growth, pollen wall assembly and modification, and pollen exine formation and pollination. The transcript profiles of 93 genes associated with pollen wall and anther development were determined by quantitative RT-PCR in different flower parts, and classified into the following three major clades: 1) up-regulated in WSLA plants; 2) down-regulated in WSLA plants; and 3) down-regulated in buds, but have a higher expression in stigmas of WSLA than in WSLB. A subset of genes associated with sporopollenin accumulation were all up-regulated in WSLA. An excess of sporopollenin results in defective pollen wall formation, which leads to male sterility in WSLA. Some of the genes identified in this study are candidates for future research, as they could provide important insight into the molecular mechanisms underlying RGMS in WSLA. PMID:26656530

  1. Light curve demography via Bayesian functional data analysis

    NASA Astrophysics Data System (ADS)

    Loredo, Thomas; Budavari, Tamas; Hendry, Martin A.; Kowal, Daniel; Ruppert, David

    2015-08-01

    Synoptic time-domain surveys provide astronomers, not simply more data, but a different kind of data: large ensembles of multivariate, irregularly and asynchronously sampled light curves. We describe a statistical framework for light curve demography—optimal accumulation and extraction of information, not only along individual light curves as conventional methods do, but also across large ensembles of related light curves. We build the framework using tools from functional data analysis (FDA), a rapidly growing area of statistics that addresses inference from datasets that sample ensembles of related functions. Our Bayesian FDA framework builds hierarchical models that describe light curve ensembles using multiple levels of randomness: upper levels describe the source population, and lower levels describe the observation process, including measurement errors and selection effects. Schematically, a particular object's light curve is modeled as the sum of a parameterized template component (modeling population-averaged behavior) and a peculiar component (modeling variability across the population), subsequently subjected to an observation model. A functional shrinkage adjustment to individual light curves emerges—an adaptive, functional generalization of the kind of adjustments made for Eddington or Malmquist bias in single-epoch photometric surveys. We are applying the framework to a variety of problems in synoptic time-domain survey astronomy, including optimal detection of weak sources in multi-epoch data, and improved estimation of Cepheid variable star luminosities from detailed demographic modeling of ensembles of Cepheid light curves.

  2. Functional principal component analysis of H-reflex recruitment curves

    PubMed Central

    Kipp, Kristof; Johnson, Samuel T; Hoffman, Mark A

    2011-01-01

    The primary purpose of this study was to use Functional Principal Component Analysis (FPCA) to analyze Hoffman-reflex (H-Reflex) recruitment curves. Smoothed and interpolated recruitment curves from 38 participants were used for analysis. Standard methods were used to calculate three discrete variables (i.e, Hmax/Mmax ratio, Hth, Hslp). FPCA was then used to extract principal component functions (PCF’s) from the processed recruitment curves. PCF scores were calculated to determine how much each PCF contributed to an individuals’ recruitment curve. The analysis extracted three PCF’s, and three sets of PCF scores. Correlation analyses and systematic variation in the PCF scores indicated that the scores for the first PCF were primarily correlated to H-reflex threshold (Hth) and that the scores for the second and third PCF’s were correlated to H-reflex magnitude (Hmax/Mmax ratio) and slope (Hslp), respectively. In addition, results from the FPCA indicated that the first PCF explained 56.0% of the variance between all H-reflex recruitment curves, whereas the second and third PCF’s explained 24.1% and 13.0%, respectively. The high correlations indicate FPCA-derived PCF’s capture similar physiological information as the standard discrete variables and suggest that application of FPCA to H-reflex recruitment curves could be used in future studies to complement traditional analyses that investigate excitability of the motoneuron pool. PMID:21402105

  3. A Quantitative Analysis of Recessions and Financial Changes in Higher Education Institution Alumni Programs

    ERIC Educational Resources Information Center

    Dos Santos, Alves

    2013-01-01

    The study examined the relationship between recession and alumni contributions to institutions of higher education for operational expenses and capital expenditures that include property, buildings, and equipment. Identifying variables that may decrease alumni contributions is important because decreased state funding for higher education…

  4. Cepheid light curve demography via Bayesian functional data analysis

    NASA Astrophysics Data System (ADS)

    Loredo, Thomas J.; Hendry, Martin; Kowal, Daniel; Ruppert, David

    2016-01-01

    Synoptic time-domain surveys provide astronomers, not simply more data, but a different kind of data: large ensembles of multivariate, irregularly and asynchronously sampled light curves. We describe a statistical framework for light curve demography—optimal accumulation and extraction of information, not only along individual light curves as conventional methods do, but also across large ensembles of related light curves. We build the framework using tools from functional data analysis (FDA), a rapidly growing area of statistics that addresses inference from datasets that sample ensembles of related functions. Our Bayesian FDA framework builds hierarchical models that describe light curve ensembles using multiple levels of randomness: upper levels describe the source population, and lower levels describe the observation process, including measurement errors and selection effects. Roughly speaking, a particular object's light curve is modeled as the sum of a parameterized template component (modeling population-averaged behavior) and a peculiar component (modeling variability across the population), subsequently subjected to an observation model. A functional shrinkage adjustment to individual light curves emerges—an adaptive, functional generalization of the kind of adjustments made for Eddington or Malmquist bias in single-epoch photometric surveys. We describe ongoing work applying the framework to improved estimation of Cepheid variable star luminosities via FDA-based refinement and generalization of the Cepheid period-luminosity relation.

  5. Estimating catchment scale groundwater dynamics from recession analysis - enhanced constraining of hydrological models

    NASA Astrophysics Data System (ADS)

    Skaugen, T.; Mengistu, Z.

    2015-10-01

    In this study we propose a new formulation of subsurface water storage dynamics for use in rainfall-runoff models. Under the assumption of a strong relationship between storage and runoff, the temporal distribution of storage is considered to have the same shape as the distribution of observed recessions (measured as the difference between the log of runoff values). The mean subsurface storage is estimated as the storage at steady-state, where moisture input equals the mean annual runoff. An important contribution of the new formulation is that its parameters are derived directly from observed recession data and the mean annual runoff and hence estimated prior to calibration. Key principles guiding the evaluation of the new subsurface storage routine have been (a) to minimize the number of parameters to be estimated through the, often arbitrary fitting to optimize runoff predictions (calibration) and (b) maximize the range of testing conditions (i.e. large-sample hydrology). The new storage routine has been implemented in the already parameter parsimonious Distance Distribution Dynamics (DDD) model and tested for 73 catchments in Norway of varying size, mean elevations and landscape types. Runoff simulations for the 73 catchments from two model structures; DDD with calibrated subsurface storage and DDD with the new estimated subsurface storage were compared. No loss in precision of runoff simulations was found using the new estimated storage routine. For the 73 catchments, an average of the Nash-Sutcliffe Efficiency criterion of 0.68 was found using the new estimated storage routine compared with 0.66 using calibrated storage routine. The average Kling-Gupta Efficiency criterion was 0.69 and 0.70 for the new and old storage routine, respectively. Runoff recessions are more realistically modelled using the new approach since the root mean square error between the mean of observed and simulated recessions was reduced by almost 50 % using the new storage routine.

  6. Fuzzy Modeling for Analysis of Load Curve in Power System

    NASA Astrophysics Data System (ADS)

    Huang, Pei-Hwa; Tseng, Ta-Hsiu; Liu, Chien-Heng; Fan, Guang-Zhong

    The main purpose of this paper is to study the use of fuzzy modeling for the analysis of customer load characteristics in power system. A fuzzy model is a collection of fuzzy IF-THEN rules for describing the features or behaviors of the data set or system under study. In view of the nonlinear characteristics of customer load demand with respect to time, the method of fuzzy modeling is adopted for analyzing the studied daily load curves. Based on the Sugeno-type fuzzy model, various models with different numbers of modeling rules have been constructed for describing the investigated power curve. Sample results are demonstrated for illustrating the effectiveness of the fuzzy model in the study of power system load curves.

  7. SurvCurv database and online survival analysis platform update

    PubMed Central

    Ziehm, Matthias; Ivanov, Dobril K.; Bhat, Aditi; Partridge, Linda; Thornton, Janet M.

    2015-01-01

    Summary: Understanding the biology of ageing is an important and complex challenge. Survival experiments are one of the primary approaches for measuring changes in ageing. Here, we present a major update to SurvCurv, a database and online resource for survival data in animals. As well as a substantial increase in data and additions to existing graphical and statistical survival analysis features, SurvCurv now includes extended mathematical mortality modelling functions and survival density plots for more advanced representation of groups of survival cohorts. Availability and implementation: The database is freely available at https://www.ebi.ac.uk/thornton-srv/databases/SurvCurv/. All data are published under the Creative Commons Attribution License. Contact: matthias.ziehm@ebi.ac.uk Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26249811

  8. The great recession of 2007 and California nurses: a descriptive analysis.

    PubMed

    Tellez, Michelle Sardenberg-Hersh; Neronde, Pamela; Wong, Sherly

    2013-05-01

    This study investigates the effect of the Recession of 2007 on nurses' wages, demographics, human capital, and work environment characteristics using data from the California Board of Registered Nursing Surveys of 2006, 2008 and 2010. Findings suggest that the labor force is maximized, with nurses working as much as they can on their primary nursing positions (51 weeks a year). As the economy recovers, the nurse shortage will resurge. Intense focus in three policy areas is recommended: education, faculty training, and recruitment and retention of African Americans, Hispanics, and older nurses. PMID:24036699

  9. Baseflow recession analysis in the inland Pacific Northwest of the United States

    NASA Astrophysics Data System (ADS)

    Sánchez-Murillo, R.; Brooks, E. S.; Elliot, W. J.; Gazel, E.; Boll, J.

    2015-03-01

    The storage-discharge relationships of 26 watersheds in the inland Pacific Northwest of the United States were analyzed. Four fitting methods were used to obtain the baseflow coefficients: lower envelope, organic correlation, and ordinary and inverse least squares. Several climatic and terrain attributes were evaluated as predictors of baseflow coefficients. Watersheds dominated by basalt and flatter landscapes exhibited the smallest recession time scales ( K) (12.5-20.0 days). Greater K values (33.3-66.7 days) were obtained over catchments dominated by metamorphic and sedimentary rocks. Mean basin slope and the aridity index were found to be the best estimators of baseflow coefficients. Baseflow in flat basalt landscapes, located in dry warm climates, decrease rapidly during summer months and are most sensitive to future droughts and warming climates. Groundwater systems feeding streams during the driest months can drop to less than 1 mm of effective storage in these sensitive systems. In contrast, the minimum annual storage in mountainous systems can have greater than 10 mm effective storage. By understanding the main factors controlling baseflow recession characteristics, environmental agencies could prioritize efforts in areas where future droughts and land use changes may affect ecological assemblages and socio-economic activities.

  10. Comprehensive Analysis of Deafness Genes in Families with Autosomal Recessive Nonsyndromic Hearing Loss

    PubMed Central

    Atik, Tahir; Onay, Huseyin; Aykut, Ayca; Bademci, Guney; Kirazli, Tayfun; Tekin, Mustafa; Ozkinay, Ferda

    2015-01-01

    Comprehensive genetic testing has the potential to become the standard of care for individuals with hearing loss. In this study, we investigated the genetic etiology of autosomal recessive nonsyndromic hearing loss (ARNSHL) in a Turkish cohort including individuals with cochlear implant, who had a pedigree suggestive of an autosomal recessive inheritance. A workflow including prescreening of GJB2 and a targeted next generation sequencing panel (Illumına TruSightTM Exome) covering 2761 genes that we briefly called as mendelian exome sequencing was used. This panel includes 102 deafness genes and a number of genes causing Mendelian disorders. Using this approach, we identified causative variants in 21 of 29 families. Three different GJB2 variants were present in seven families. Remaining 14 families had 15 different variants in other known NSHL genes (MYO7A, MYO15A, MARVELD2, TMIE, DFNB31, LOXHD1, GPSM2, TMC1, USH1G, CDH23). Of these variants, eight are novel. Mutation detection rate of our workflow is 72.4%, confirming the usefulness of targeted sequencing approach in NSHL. PMID:26561413

  11. On the restricted mean survival time curve in survival analysis.

    PubMed

    Zhao, Lihui; Claggett, Brian; Tian, Lu; Uno, Hajime; Pfeffer, Marc A; Solomon, Scott D; Trippa, Lorenzo; Wei, L J

    2016-03-01

    For a study with an event time as the endpoint, its survival function contains all the information regarding the temporal, stochastic profile of this outcome variable. The survival probability at a specific time point, say t, however, does not transparently capture the temporal profile of this endpoint up to t. An alternative is to use the restricted mean survival time (RMST) at time t to summarize the profile. The RMST is the mean survival time of all subjects in the study population followed up to t, and is simply the area under the survival curve up to t. The advantages of using such a quantification over the survival rate have been discussed in the setting of a fixed-time analysis. In this article, we generalize this approach by considering a curve based on the RMST over time as an alternative summary to the survival function. Inference, for instance, based on simultaneous confidence bands for a single RMST curve and also the difference between two RMST curves are proposed. The latter is informative for evaluating two groups under an equivalence or noninferiority setting, and quantifies the difference of two groups in a time scale. The proposal is illustrated with the data from two clinical trials, one from oncology and the other from cardiology. PMID:26302239

  12. Instrumentation for automated acquisition and analysis of TLD glow curves

    NASA Astrophysics Data System (ADS)

    Bostock, I. J.; Kennett, T. J.; Harvey, J. W.

    1991-04-01

    Instrumentation for the automated and complete acquisition of thermoluminescent dosimeter (TLD) data from a Panasonic UD-702E TLD reader is reported. The system that has been developed consists of both hardware and software components and is designed to operate with an IBM-type personal computer. Acquisition of glow curve, timing, and heating data has been integrated with elementary numerical analysis to permit real-time validity and diagnostic assessments to be made. This allows the optimization of critical parameters such as duration of the heating cycles and the time window for the integration of the dosimetry peak. The form of the Li 2B 4O 7:Cu TLD glow curve has been studied and a mathematical representation devised to assist in the implementation of automated analysis. Differences in the shape of the curve can be used to identify dosimetry peaks due to artifacts or to identify failing components. Examples of the use of this system for quality assurance in the TLD monitoring program at McMaster University are presented.

  13. Multi-wavelength analysis of Ellerman Bomb Light Curves

    NASA Astrophysics Data System (ADS)

    Herlender, M.; Berlicki, A.

    We present the results of a multi-wavelength photometric analysis of Ellerman Bomb (EB) observations obtained from the Dutch Open Telescope. In our data we have found 6 EBs located in the super-penumbra of the main spot in the active region NOAA 10781. We present light curves of EB observed in the Hα line centre and wing +0.7 Å, in the Ca II H line centre and wing~+2.35 Å, in the G-band and in the TRACE 1600 Å filter. We have shown that EBs were visible in the G-band and moreover, there was a good correlation between the light curves in the G-band and in the Hα line wings. We also found quasi-periodic oscillations of EBs brightness in the G-band, CaII H line and TRACE 1600 Å filter.

  14. Stress analysis in curved composites due to thermal loading

    NASA Astrophysics Data System (ADS)

    Polk, Jared Cornelius

    Many structures in aircraft, cars, trucks, ships, machines, tools, bridges, and buildings, consist of curved sections. These sections vary from straight line segments that have curvature at either one or both ends, segments with compound curvatures, segments with two mutually perpendicular curvatures or Gaussian curvatures, and segments with a simple curvature. With the advancements made in multi-purpose composites over the past 60 years, composites slowly but steadily have been appearing in these various vehicles, compound structures, and buildings. These composite sections provide added benefits over isotropic, polymeric, and ceramic materials by generally having a higher specific strength, higher specific stiffnesses, longer fatigue life, lower density, possibilities in reduction of life cycle and/or acquisition cost, and greater adaptability to intended function of structure via material composition and geometry. To be able to design and manufacture a safe composite laminate or structure, it is imperative that the stress distributions, their causes, and effects are thoroughly understood in order to successfully accomplish mission objectives and manufacture a safe and reliable composite. The objective of the thesis work is to expand upon the knowledge of simply curved composite structures by exploring and ascertaining all pertinent parameters, phenomenon, and trends in stress variations in curved laminates due to thermal loading. The simply curved composites consist of composites with one radius of curvature throughout the span of the specimen about only one axis. Analytical beam theory, classical lamination theory, and finite element analysis were used to ascertain stress variations in a flat, isotropic beam. An analytical method was developed to ascertain the stress variations in an isotropic, simply curved beam under thermal loading that is under both free-free and fixed-fixed constraint conditions. This is the first such solution to Author's best knowledge of such a problem. It was ascertained and proven that the general, non-modified (original) version of classical lamination theory cannot be used for an analytical solution for a simply curved beam or any other structure that would require rotations of laminates out their planes in space. Finite element analysis was used to ascertain stress variations in a simply curved beam. It was verified that these solutions reduce to the flat beam solutions as the radius of curvature of the beams tends to infinity. MATLAB was used to conduct the classical lamination theory numerical analysis. A MATLAB program was written to conduct the finite element analysis for the flat and curved beams, isotropic and composite. It does not require incompatibility techniques used in mechanics of isotropic materials for indeterminate structures that are equivalent to fixed-beam problems. Finally, it has the ability to enable the user to define and create unique elements not accessible in commercial software, and modify finite element procedures to take advantage of new paradigms.

  15. A new approach to the analysis of Mira light curves

    NASA Technical Reports Server (NTRS)

    Mennessier, M. O.; Barthes, D.; Mattei, J. A.

    1990-01-01

    Two different but complementary methods for predicting Mira luminosities are presented. One method is derived from a Fourier analysis, it requires performing deconvolution, and its results are not certain due to the inherent instability of deconvolution problems. The other method is a learning method utilizing artificial intelligence techniques where a light curve is presented as an ordered sequence of pseudocycles, and rules are learned by linking the characteristics of several consecutive pseudocycles to one characteristic of the future cycle. It is observed that agreement between these methods is obtainable when it is possible to eliminate similar false frequencies from the preliminary power spectrum and to improve the degree of confidence in the rules.

  16. FMRI Signal Analysis Using Empirical Mean Curve Decomposition

    PubMed Central

    Deng, Fan; Zhu, Dajiang; Lv, Jinglei; Guo, Lei; Liu, Tianming

    2013-01-01

    Functional magnetic resonance imaging (fMRI) time series is non-linear and composed of components at multiple temporal scales, which presents significant challenges to its analysis. In the literature, significant effort has been devoted into model-based fMRI signal analysis, while much less attention has been directed to data-driven fMRI signal analysis. In this paper, we present a novel data-driven multi-scale signal decomposition framework named Empirical Mean Curve Decomposition (EMCD). Targeted on functional brain mapping, the EMCD optimizes mean envelopes from fMRI signals and iteratively extracts coarser-to-finer scale signal components. The EMCD framework was applied to infer meaningful low-frequency information from Blood Oxygenation Level Dependent (BOLD) signals from resting state fMRI, task-based fMRI, and natural stimulus fMRI, and promising results are obtained. PMID:23047856

  17. Exclusion of the locus for autosomal recessive pseudohypoaldosteronism type 1 from the mineralocorticoid receptor gene region on human chromosome 4q by linkage analysis

    SciTech Connect

    Chung, E.; Hanukoglu, A.; Rees, M.; Thompson, R.; Gardiner, R.M.

    1995-10-01

    Pseudohypoaldosteronism type 1 (PHA1) is an uncommon inherited disorder characterized by salt-wasting in infancy arising from target organ unresponsiveness to mineralocorticoids. Clinical expression of the disease varies from severely affected infants who may die to apparently asymptomatic individuals. Inheritance is Mendelian and may be either autosomal dominant or autosomal recessive. A defect in the mineralocortiocoid receptor has been implicated as a likely cause of PHA1. The gene for human mineralocorticoid receptor (MLR) has been cloned and physically mapped to human chromosome 4q31.1-31.2. The etiological role of MLR in autosomal recessive PHA1 was investigated by performing linkage analysis between PHA1 and three simple sequence length polymorphisms (D4S192, D4S1548, and D4S413) on chromosome 4q in 10 consanguineous families. Linkage analysis was carried out assuming autosomal recessive inheritance with full penetrance and zero phenocopy rate using the MLINK program for two-point analysis and the HOMOZ program for multipoint analysis. Lod scores of less than -2 were obtained over the whole region from D4S192 to D4S413 encompassing MLR. This provides evidence against MLR as the site of mutations causing PHA1 in the majority of autosomal recessive families. 34 refs., 3 figs., 2 tabs.

  18. An item response curves analysis of the Force Concept Inventory

    NASA Astrophysics Data System (ADS)

    Morris, Gary A.; Harshman, Nathan; Branum-Martin, Lee; Mazur, Eric; Mzoughi, Taha; Baker, Stephen D.

    2012-09-01

    Several years ago, we introduced the idea of item response curves (IRC), a simplistic form of item response theory (IRT), to the physics education research community as a way to examine item performance on diagnostic instruments such as the Force Concept Inventory (FCI). We noted that a full-blown analysis using IRT would be a next logical step, which several authors have since taken. In this paper, we show that our simple approach not only yields similar conclusions in the analysis of the performance of items on the FCI to the more sophisticated and complex IRT analyses but also permits additional insights by characterizing both the correct and incorrect answer choices. Our IRC approach can be applied to a variety of multiple-choice assessments but, as applied to a carefully designed instrument such as the FCI, allows us to probe student understanding as a function of ability level through an examination of each answer choice. We imagine that physics teachers could use IRC analysis to identify prominent misconceptions and tailor their instruction to combat those misconceptions, fulfilling the FCI authors' original intentions for its use. Furthermore, the IRC analysis can assist test designers to improve their assessments by identifying nonfunctioning distractors that can be replaced with distractors attractive to students at various ability levels.

  19. Concentrated photovoltaics system costs and learning curve analysis

    NASA Astrophysics Data System (ADS)

    Haysom, Joan E.; Jafarieh, Omid; Anis, Hanan; Hinzer, Karin

    2013-09-01

    An extensive set of costs in /W for the installed costs of CPV systems has been amassed from a range of public sources, including both individual company prices and market reports. Cost reductions over time are very evident, with current prices for 2012 in the range of 3.0 ± 0.7 /W and a predicted cost of 1.5 /W for 2020. Cost data is combined with deployment volumes in a learning curve analysis, providing a fitted learning rate of either 18.5% or 22.3% depending on the methodology. This learning rate is compared to that of PV modules and PV installed systems, and the influence of soft costs is discussed. Finally, if an annual growth rate of 39% is assumed for deployed volumes, then, using the learning rate of 20%, this would predict the achievement of a cost point of 1.5 /W by 2016.

  20. Sex-linked recessive

    MedlinePlus

    ... Males have only one X chromosome. A single recessive gene on that X chromosome will cause the disease. ... hemophilia and Duchenne muscular dystrophy occur from a recessive gene on the X chromosome. TYPICAL SCENARIOS In each ...

  1. Analysis of selected Kepler Mission planetary light curves

    NASA Astrophysics Data System (ADS)

    Rhodes, M. D.; Budding, E.

    2014-06-01

    We have modified the graphical user interfaced close binary system analysis program CurveFit to the form WinKepler and applied it to 16 representative planetary candidate light curves found in the NASA Exoplanet Archive (NEA) at the Caltech website http://exoplanetarchive.ipac.caltech.edu, with an aim to compare different analytical approaches. WinKepler has parameter options for a realistic physical model, including gravity-brightening and structural parameters derived from the relevant Radau equation. We tested our best-fitting parameter-sets for formal determinacy and adequacy. A primary aim is to compare our parameters with those listed in the NEA. Although there are trends of agreement, small differences in the main parameter values are found in some cases, and there may be some relative bias towards a 90? value for the NEA inclinations. These are assessed against realistic error estimates. Photometric variability from causes other than planetary transits affects at least 6 of the data-sets studied; with small pulsational behaviour found in 3 of those. For the false positive KOI 4.01, we found that the eclipses could be modelled by a faint background classical Algol as effectively as by a transiting exoplanet. Our empirical checks of limb-darkening, in the cases of KOI 1.01 and 12.01, revealed that the assigned stellar temperatures are probably incorrect. For KOI 13.01, our empirical mass-ratio differs by about 7 % from that of Mislis and Hodgkin (Mon. Not. R. Astron. Soc. 422:1512, 2012), who neglected structural effects and higher order terms in the tidal distortion. Such detailed parameter evaluation, additional to the usual main geometric ones, provides an additional objective for this work.

  2. Learning curve analysis of a patient lift-assist device.

    PubMed

    Reid, Stephanie A; Mirka, Gary A

    2007-11-01

    One of the challenges facing ergonomists in the implementation of an ergonomic solution is addressing the concerns related to their impact on productivity. The focus of the current study was to (1) apply standard learning curve analysis to the learning that takes place as an individual works with a patient handling device and (2) compare the effects of two different training protocols on measures of learning. Eighteen subjects completed 11 replications of a patient transfer task after participating in either an "interactive" training protocol or "see-one-do-one" training protocol. The results show that the learning rate for this task was 83% with no difference as a function of training protocol. The results do indicate that the effect of Training Method was significant (p<0.05) for time to complete the first patient lift task (370s for the interactive training vs. 475s for see-one-do-one training). The results of the analysis of the survey data supported the objective results in that the only measure that was responsive to training type (p<0.05) was related to comfort level in performing the patient lift task for the first time. The results emphasize the importance in considering learning when introducing an intervention in the workplace, and showed that in this instance, training type had an immediate impact on productivity, but that this effect diminished over time. PMID:17194439

  3. Autosomal recessive cerebellar ataxias

    PubMed Central

    Palau, Francesc; Espinós, Carmen

    2006-01-01

    Autosomal recessive cerebellar ataxias (ARCA) are a heterogeneous group of rare neurological disorders involving both central and peripheral nervous system, and in some case other systems and organs, and characterized by degeneration or abnormal development of cerebellum and spinal cord, autosomal recessive inheritance and, in most cases, early onset occurring before the age of 20 years. This group encompasses a large number of rare diseases, the most frequent in Caucasian population being Friedreich ataxia (estimated prevalence 2–4/100,000), ataxia-telangiectasia (1–2.5/100,000) and early onset cerebellar ataxia with retained tendon reflexes (1/100,000). Other forms ARCA are much less common. Based on clinicogenetic criteria, five main types ARCA can be distinguished: congenital ataxias (developmental disorder), ataxias associated with metabolic disorders, ataxias with a DNA repair defect, degenerative ataxias, and ataxia associated with other features. These diseases are due to mutations in specific genes, some of which have been identified, such as frataxin in Friedreich ataxia, α-tocopherol transfer protein in ataxia with vitamin E deficiency (AVED), aprataxin in ataxia with oculomotor apraxia (AOA1), and senataxin in ataxia with oculomotor apraxia (AOA2). Clinical diagnosis is confirmed by ancillary tests such as neuroimaging (magnetic resonance imaging, scanning), electrophysiological examination, and mutation analysis when the causative gene is identified. Correct clinical and genetic diagnosis is important for appropriate genetic counseling and prognosis and, in some instances, pharmacological treatment. Due to autosomal recessive inheritance, previous familial history of affected individuals is unlikely. For most ARCA there is no specific drug treatment except for coenzyme Q10 deficiency and abetalipoproteinemia. PMID:17112370

  4. Update on autosomal recessive congenital ichthyosis: mRNA analysis using hair samples is a powerful tool for genetic diagnosis.

    PubMed

    Sugiura, Kazumitsu; Akiyama, Masashi

    2015-07-01

    Research on the molecular genetics and pathomechanisms of autosomal recessive congenital ichthyosis (ARCI) has advanced considerably and several causative genes and molecules underlying the disease have been identified. Three major ARCI phenotypes are harlequin ichthyosis (HI), lamellar ichthyosis (LI), and congenital ichthyosiform erythroderma (CIE). Skin barrier defects are involved in the pathogenesis of ARCI. In this review, the causative genes of ARCI and its phenotypes as well as recent advances in the field are summarized. The known causative molecules underlying ARCI include ABCA12, TGM1, ALOXE3, ALOX12B, NIPAL4, CYP4F22, PNPLA1, CERS3, and LIPN. It is important to examine genetic associations and to elucidate the pathomechanisms of ARCI to establish effective therapies and beneficial genetic counseling. Next-generation sequencing is a promising method that enables the detection of causative disease mutations, even in cases of unexpected concomitant genetic diseases. For genetic diagnosis, obtaining mRNA from hair follicle epithelial cells, which are analogous to keratinocytes in the interfollicular epidermis, is convenient and minimally invasive in patients with ARCI. We confirmed that our mRNA analysis method using hair follicle samples can be applied not only to keratinization disorders, but also to other genetic diseases in the dermatology field. Studies that suggest potential next-generation therapies using ARCI model mice are also reviewed. PMID:25982146

  5. Three-Dimensional Postbuckling Analysis of Curved Beams

    NASA Technical Reports Server (NTRS)

    Pai, P. Frank; Lee, Seung-Yoon

    2002-01-01

    Presented here is a method of solving highly flexible curved beam undergoing huge static or quasi-static deformations. A geometrically exact beam theory based on the use of Jaumann stresses and strains and exact coordinate transformation is presented in terms of 17 first-order ordinary differential equations, and a multiple shooting method is used to solve the corresponding nonlinear two-point boundary value problems. The geometrically exact beam theory accounts far large rotations, large displacements, initial curvatures, extensionality, and transverse shear strains. Four examples are used to demonstrate this method, including a rotating clamped-free beam under the influence of gravity and centrifugal forces, an L-frame subjected to an in-plane tip load, a circular arch subjected to a concentrated load, and a clamped-hinged helical spring subjected to an axial displacement. Results show that the combination of the multiple shooting method and the geometrically exact beam theory works very well. Moreover, the obtained numerically exact solutions can be used to verify the accuracy of nonlinear finite element codes for nonlinear analysis of complex structures.

  6. Estimated hydrologic characteristics of shallow aquifer systems in the Valley and Ridge, the Blue Ridge, and the Piedmont physiographic provinces based on analysis of streamflow recession and base flow

    USGS Publications Warehouse

    Rutledge, A.T.; Mesko, T.O.

    1996-01-01

    Inferences are drawn about properties of aquifer systems from the interpretation of streamflow records in the Appalachian Valley and Ridge, Piedmont, and Blue Ridge physiographic provinces. The analysis is divided into two parts--analysis of streamflow recession and base-flow analysis. Analysis of recession yields information about aquifer diffusivity and variation in specific yield. Base-flow analysis is used to develop water balances for representative basins in the study area.

  7. [Gingival recessions and orthodontics].

    PubMed

    Renkema, A M; Padmos, J A D; de Quincey, G de

    2015-11-01

    Gingival recessions represent the most visible periodontal disease. The prevalence of gingival recessions is high. The root surface is literally exposed to negative influences such as erosion, abrasion, discoloration and decay. Moreover, gingival recessions can affect the quality of life by increased thermal sensitivity and reduced dento-gingival aesthetics. The aetiology of gingival recessions is complex and considered to be multifactorial. In order to prevent the development of gingival recessions during and after orthodontic treatment, several factors should be taken into account, among which maintenance of optimal oral hygiene and respect for the 'biological envelope' are decisive. Once gingival recessions have developed, orthodontic therapy can play a positive role in their treatment. PMID:26569002

  8. Automatic generation and analysis of solar cell IV curves

    SciTech Connect

    Kraft, Steven M.; Jones, Jason C.

    2014-06-03

    A photovoltaic system includes multiple strings of solar panels and a device presenting a DC load to the strings of solar panels. Output currents of the strings of solar panels may be sensed and provided to a computer that generates current-voltage (IV) curves of the strings of solar panels. Output voltages of the string of solar panels may be sensed at the string or at the device presenting the DC load. The DC load may be varied. Output currents of the strings of solar panels responsive to the variation of the DC load are sensed to generate IV curves of the strings of solar panels. IV curves may be compared and analyzed to evaluate performance of and detect problems with a string of solar panels.

  9. Optical analysis of miniature lenses with curved imaging surfaces.

    PubMed

    Reshidko, Dmitry; Sasian, Jose

    2015-10-01

    Miniature cameras for consumer electronics and mobile phones have been, and continue to be, in fast development. The system level requirements, such as manufacturing cost, packaging, and sensor characteristics, impose unique challenges for optical designers. In this paper, we discuss the potential optical benefits of having a curved image surface rather than a flat one. We show that curved sensor technology allows for optically faster lens solutions. We discuss trade-offs of several relevant characteristics, such as packaging, chief ray angle, image quality, and tolerance sensitivity. A comparison of a benchmark flat field lens, and an evaluation design imaging on a curved surface and working at f/1.6, provides useful specific insights. For a given image quality, departing from a flat imaging surface does not allow significantly reducing the total length of a lens. PMID:26479656

  10. Linear analysis of naturally curved and twisted anisotropic beam

    NASA Astrophysics Data System (ADS)

    Borri, Marco; Ghiringhelli, Gian L.; Merlini, Teodoro

    1991-05-01

    The determination of the governing equations of a naturally curved and twisted anisotropic beam is presently addressed by a model which takes into account all elastic couplings due to the material and the curved geometry, under the assumption of uniformity in cross-section, curvature and twist. While requiring only a 2D approximation, a degree of detail is achieved which would be unrealistic in a 3D approach. The FEM of the beam cross section furnishes a useful mathematical tool for the tailoring of practical helicopter rotor blade designs.

  11. Developmental Trajectories of Adolescent Popularity: A Growth Curve Modelling Analysis

    ERIC Educational Resources Information Center

    Cillessen, Antonius H. N.; Borch, Casey

    2006-01-01

    Growth curve modelling was used to examine developmental trajectories of sociometric and perceived popularity across eight years in adolescence, and the effects of gender, overt aggression, and relational aggression on these trajectories. Participants were 303 initially popular students (167 girls, 136 boys) for whom sociometric data were…

  12. UNSUPERVISED TRANSIENT LIGHT CURVE ANALYSIS VIA HIERARCHICAL BAYESIAN INFERENCE

    SciTech Connect

    Sanders, N. E.; Soderberg, A. M.; Betancourt, M.

    2015-02-10

    Historically, light curve studies of supernovae (SNe) and other transient classes have focused on individual objects with copious and high signal-to-noise observations. In the nascent era of wide field transient searches, objects with detailed observations are decreasing as a fraction of the overall known SN population, and this strategy sacrifices the majority of the information contained in the data about the underlying population of transients. A population level modeling approach, simultaneously fitting all available observations of objects in a transient sub-class of interest, fully mines the data to infer the properties of the population and avoids certain systematic biases. We present a novel hierarchical Bayesian statistical model for population level modeling of transient light curves, and discuss its implementation using an efficient Hamiltonian Monte Carlo technique. As a test case, we apply this model to the Type IIP SN sample from the Pan-STARRS1 Medium Deep Survey, consisting of 18,837 photometric observations of 76 SNe, corresponding to a joint posterior distribution with 9176 parameters under our model. Our hierarchical model fits provide improved constraints on light curve parameters relevant to the physical properties of their progenitor stars relative to modeling individual light curves alone. Moreover, we directly evaluate the probability for occurrence rates of unseen light curve characteristics from the model hyperparameters, addressing observational biases in survey methodology. We view this modeling framework as an unsupervised machine learning technique with the ability to maximize scientific returns from data to be collected by future wide field transient searches like LSST.

  13. Unsupervised Transient Light Curve Analysis via Hierarchical Bayesian Inference

    NASA Astrophysics Data System (ADS)

    Sanders, N. E.; Betancourt, M.; Soderberg, A. M.

    2015-02-01

    Historically, light curve studies of supernovae (SNe) and other transient classes have focused on individual objects with copious and high signal-to-noise observations. In the nascent era of wide field transient searches, objects with detailed observations are decreasing as a fraction of the overall known SN population, and this strategy sacrifices the majority of the information contained in the data about the underlying population of transients. A population level modeling approach, simultaneously fitting all available observations of objects in a transient sub-class of interest, fully mines the data to infer the properties of the population and avoids certain systematic biases. We present a novel hierarchical Bayesian statistical model for population level modeling of transient light curves, and discuss its implementation using an efficient Hamiltonian Monte Carlo technique. As a test case, we apply this model to the Type IIP SN sample from the Pan-STARRS1 Medium Deep Survey, consisting of 18,837 photometric observations of 76 SNe, corresponding to a joint posterior distribution with 9176 parameters under our model. Our hierarchical model fits provide improved constraints on light curve parameters relevant to the physical properties of their progenitor stars relative to modeling individual light curves alone. Moreover, we directly evaluate the probability for occurrence rates of unseen light curve characteristics from the model hyperparameters, addressing observational biases in survey methodology. We view this modeling framework as an unsupervised machine learning technique with the ability to maximize scientific returns from data to be collected by future wide field transient searches like LSST.

  14. More Recess Time, Please!

    ERIC Educational Resources Information Center

    Chang, Rong; Coward, Fanni Liu

    2015-01-01

    Students in Shanghai, China, get much more recess time than their U.S. counterparts throughout their education. As U.S. education reform efforts seek ways of raising achievement, they have begun replacing recess with academic time. The lesson from Shanghai is that this may not be the best strategy. But whether the Shanghai system of more and

  15. More Recess Time, Please!

    ERIC Educational Resources Information Center

    Chang, Rong; Coward, Fanni Liu

    2015-01-01

    Students in Shanghai, China, get much more recess time than their U.S. counterparts throughout their education. As U.S. education reform efforts seek ways of raising achievement, they have begun replacing recess with academic time. The lesson from Shanghai is that this may not be the best strategy. But whether the Shanghai system of more and…

  16. Starving for Recess

    ERIC Educational Resources Information Center

    Patt, Mary Johnson

    2011-01-01

    Every weekday, millions of American schoolchildren throw away their half-eaten cafeteria lunches so that they can run outside to play. The traditional placement of lunch before recess, coupled with the recent decline in overall recess time to meet academic time constraints, forces children to choose between two essential needs: (1) food; and (2)…

  17. Recess Makes Kids Smarter

    ERIC Educational Resources Information Center

    Adams, Caralee

    2011-01-01

    Recess has been scaled back or cut altogether in a number of schools around the country. The trend can be traced back to the late eighties and was accelerated under No Child Left Behind. Districts under pressure to show academic progress began to squeeze as much instruction into the day as possible. Others eliminated recess because of concerns…

  18. Recess--It's Indispensable!

    ERIC Educational Resources Information Center

    Jarrett, Olga; Waite-Stupiansky, Sandra

    2009-01-01

    The demise of recess in many elementary schools--and of outdoor play in general--is an issue of great concern to many members of the Play, Policy, and Practice Interest Forum. Most people remember recess as an important part of the school day. It was a time to be outdoors; to organize games; to play on the swings, slides, and other playground…

  19. Efficient Perturbation Analysis of Lamb Wave Dispersion Curves

    NASA Astrophysics Data System (ADS)

    Gandhi, Navneet; Michaels, Jennifer E.

    2010-02-01

    Lamb waves are frequently used in nondestructive evaluation and are proposed for structural health monitoring applications. While many numerical methods to obtain dispersion curves for Lamb waves have been developed and implemented, in general they are time consuming and do not lend themselves to analyses involving the perturbation of parameters such as the small thickness and wave speed changes caused by temperature variations. Presented here are two methods of approximating the solutions of the Rayleigh-Lamb equations under a small perturbation assumption. The first method is a gradient-based linear approximation to the Raleigh-Lamb equations, and the second is a linear approximation method based on a number of pre-computed solutions to the Rayleigh-Lamb equations. Also presented is a simple algorithm to efficiently compute Lamb wave dispersion curves, which is used to study the approximation methods.

  20. Curved Thermopiezoelectric Shell Structures Modeled by Finite Element Analysis

    NASA Technical Reports Server (NTRS)

    Lee, Ho-Jun

    2000-01-01

    "Smart" structures composed of piezoelectric materials may significantly improve the performance of aeropropulsion systems through a variety of vibration, noise, and shape-control applications. The development of analytical models for piezoelectric smart structures is an ongoing, in-house activity at the NASA Glenn Research Center at Lewis Field focused toward the experimental characterization of these materials. Research efforts have been directed toward developing analytical models that account for the coupled mechanical, electrical, and thermal response of piezoelectric composite materials. Current work revolves around implementing thermal effects into a curvilinear-shell finite element code. This enhances capabilities to analyze curved structures and to account for coupling effects arising from thermal effects and the curved geometry. The current analytical model implements a unique mixed multi-field laminate theory to improve computational efficiency without sacrificing accuracy. The mechanics can model both the sensory and active behavior of piezoelectric composite shell structures. Finite element equations are being implemented for an eight-node curvilinear shell element, and numerical studies are being conducted to demonstrate capabilities to model the response of curved piezoelectric composite structures (see the figure).

  1. Thermoluminescence glow curve analysis and CGCD method for erbium doped CaZrO3 phosphor

    NASA Astrophysics Data System (ADS)

    Tiwari, Ratnesh; Chopra, Seema

    2016-05-01

    The manuscript report the synthesis, thermoluminescence study at fixed concentration of Er3+ (1 mol%) doped CaZrO3 phosphor. The phosphors were prepared by modified solid state reaction method. The powder sample was characterized by thermoluminescence (TL) glow curve analysis. In TL glow curve the optimized concentration in 1mol% for UV irradiated sample. The kinetic parameters were calculated by computerized glow curve deconvolution (CGCD) techniaue. Trapping parameters gives the information of dosimetry loss in prepared phosphor and its usability in environmental monitoring and for personal monitoring. CGCD is the advance tool for analysis of complicated TL glow curves.

  2. Understanding Recession and Self-Rated Health with the Partial Proportional Odds Model: An Analysis of 26 Countries

    PubMed Central

    Mayer, Adam; Foster, Michelle

    2015-01-01

    Introduction Self-rated health is demonstrated to vary substantially by both personal socio-economic status and national economic conditions. However, studies investigating the combined influence of individual and country level economic indicators across several countries in the context of recent global recession are limited. This paper furthers our knowledge of the effect of recession on health at both the individual and national level. Methods Using the Life in Transition II study, which provides data from 19,759 individuals across 26 European nations, we examine the relationship between self-rated health, personal economic experiences, and macro-economic change. Data analyses include, but are not limited to, the partial proportional odds model which permits the effect of predictors to vary across different levels of our dependent variable. Results Household experiences with recession, especially a loss of staple good consumption, are associated with lower self-rated health. Most individual-level experiences with recession, such as a job loss, have relatively small negative effects on perceived health; the effect of individual or household economic hardship is strongest in high income nations. Our findings also suggest that macroeconomic growth improves self-rated health in low-income nations but has no effect in high-income nations. Individuals with the greatest probability of “good” self-rated health reside in wealthy countries ($23,910 to $50, 870 GNI per capita). Conclusion Both individual and national economic variables are predictive of self-rated health. Personal and household experiences are most consequential for self-rated health in high income nations, while macroeconomic growth is most consequential in low-income nations. PMID:26513660

  3. Transit light curves with finite integration time: Fisher information analysis

    SciTech Connect

    Price, Ellen M.; Rogers, Leslie A.

    2014-10-10

    Kepler has revolutionized the study of transiting planets with its unprecedented photometric precision on more than 150,000 target stars. Most of the transiting planet candidates detected by Kepler have been observed as long-cadence targets with 30 minute integration times, and the upcoming Transiting Exoplanet Survey Satellite will record full frame images with a similar integration time. Integrations of 30 minutes affect the transit shape, particularly for small planets and in cases of low signal to noise. Using the Fisher information matrix technique, we derive analytic approximations for the variances and covariances on the transit parameters obtained from fitting light curve photometry collected with a finite integration time. We find that binning the light curve can significantly increase the uncertainties and covariances on the inferred parameters when comparing scenarios with constant total signal to noise (constant total integration time in the absence of read noise). Uncertainties on the transit ingress/egress time increase by a factor of 34 for Earth-size planets and 3.4 for Jupiter-size planets around Sun-like stars for integration times of 30 minutes compared to instantaneously sampled light curves. Similarly, uncertainties on the mid-transit time for Earth and Jupiter-size planets increase by factors of 3.9 and 1.4. Uncertainties on the transit depth are largely unaffected by finite integration times. While correlations among the transit depth, ingress duration, and transit duration all increase in magnitude with longer integration times, the mid-transit time remains uncorrelated with the other parameters. We provide code in Python and Mathematica for predicting the variances and covariances at www.its.caltech.edu/∼eprice.

  4. Genetics Home Reference: autosomal recessive primary microcephaly

    MedlinePlus

    ... This Page Cox J, Jackson AP, Bond J, Woods CG. What primary microcephaly can tell us about ... Mannon J, Rashid Y, Crow Y, Bond J, Woods CG. Autosomal recessive primary microcephaly: an analysis of ...

  5. What mainly controls recession flows in river basins?

    NASA Astrophysics Data System (ADS)

    Biswal, Basudev; Nagesh Kumar, D.

    2014-03-01

    The ubiquity of the power law relationship between dQ/dt and Q for recession periods (-dQ/dt=kQα,Q being discharge at the basin outlet at time t) clearly hints at the existence of a dominant recession flow process that is common to all real basins. It is commonly assumed that a basin, during recession events, functions as a single phreatic aquifer resting on a impermeable horizontal bed or the Dupuit-Boussinesq (DB) aquifer, and with time different aquifer geometric conditions arise that give different values of α and k. The recently proposed alternative model, geomorphological recession flow model, however, suggests that recession flows are controlled primarily by the dynamics of the active drainage network (ADN). In this study we use data for several basins and compare the above two contrasting recession flow models in order to understand which of the above two factors dominates during recession periods in steep basins. Particularly, we do the comparison by selecting three key recession flow properties: (1) power law exponent α, (2) dynamic dQ/dt-Q relationship (characterized by k) and (3) recession timescale (time period for which a recession event lasts). Our observations suggest that neither drainage from phreatic aquifers nor evapotranspiration significantly controls recession flows. Results show that the value of α and recession timescale are not modeled well by DB aquifer model. However, the above mentioned three recession curve properties can be captured satisfactorily by considering the dynamics of the ADN as described by geomorphological recession flow model, possibly indicating that the ADN represents not just phreatic aquifers but the organization of various sub-surface storage systems within the basin.

  6. Meta-analysis of Diagnostic Accuracy and ROC Curves with Covariate Adjusted Semiparametric Mixtures.

    PubMed

    Doebler, Philipp; Holling, Heinz

    2015-12-01

    Many screening tests dichotomize a measurement to classify subjects. Typically a cut-off value is chosen in a way that allows identification of an acceptable number of cases relative to a reference procedure, but does not produce too many false positives at the same time. Thus for the same sample many pairs of sensitivities and false positive rates result as the cut-off is varied. The curve of these points is called the receiver operating characteristic (ROC) curve. One goal of diagnostic meta-analysis is to integrate ROC curves and arrive at a summary ROC (SROC) curve. Holling, Böhning, and Böhning (Psychometrika 77:106-126, 2012a) demonstrated that finite semiparametric mixtures can describe the heterogeneity in a sample of Lehmann ROC curves well; this approach leads to clusters of SROC curves of a particular shape. We extend this work with the help of the [Formula: see text] transformation, a flexible family of transformations for proportions. A collection of SROC curves is constructed that approximately contains the Lehmann family but in addition allows the modeling of shapes beyond the Lehmann ROC curves. We introduce two rationales for determining the shape from the data. Using the fact that each curve corresponds to a natural univariate measure of diagnostic accuracy, we show how covariate adjusted mixtures lead to a meta-regression on SROC curves. Three worked examples illustrate the method. PMID:25361619

  7. GLOBAL ANALYSIS OF KOI-977: SPECTROSCOPY, ASTEROSEISMOLOGY, AND PHASE-CURVE ANALYSIS

    SciTech Connect

    Hirano, Teruyuki; Sato, Bun'ei; Kobayashi, Atsushi; Masuda, Kento; Benomar, Othman; Takeda, Yoichi; Omiya, Masashi; Harakawa, Hiroki

    2015-01-20

    We present a global analysis of KOI-977, one of the planet host candidates detected by Kepler. The Kepler Input Catalog (KIC) reports that KOI-977 is a red giant, for which few close-in planets have been discovered. Our global analysis involves spectroscopic and asteroseismic determinations of stellar parameters (e.g., mass and radius) and radial velocity (RV) measurements. Our analyses reveal that KOI-977 is indeed a red giant, possibly in the red clump, but its estimated radius (≳ 20 R {sub ☉} = 0.093 AU) is much larger than KOI-977.01's orbital distance (∼0.027 AU) estimated from its period (P {sub orb} ∼ 1.35 days) and host star's mass. RV measurements show a small variation, which also contradicts the amplitude of ellipsoidal variations seen in the light curve folded with KOI-977.01's period. Therefore, we conclude that KOI-977.01 is a false positive, meaning that the red giant, for which we measured the radius and RVs, is different from the object that produces the transit-like signal (i.e., an eclipsing binary). On the basis of this assumption, we also perform a light curve analysis including the modeling of transits/eclipses and phase-curve variations, adopting various values for the dilution factor D, which is defined as the flux ratio between the red giant and eclipsing binary. Fitting the whole folded light curve as well as individual transits in the short cadence data simultaneously, we find that the estimated mass and radius ratios of the eclipsing binary are consistent with those of a solar-type star and a late-type star (e.g., an M dwarf) for D ≳ 20.

  8. Parent involvement and science achievement: A latent growth curve analysis

    NASA Astrophysics Data System (ADS)

    Johnson, Ursula Yvette

    This study examined science achievement growth across elementary and middle school and parent school involvement using the Early Childhood Longitudinal Study - Kindergarten Class of 1998--1999 (ECLS-K). The ECLS-K is a nationally representative kindergarten cohort of students from public and private schools who attended full-day or half-day kindergarten class in 1998--1999. The present study's sample (N = 8,070) was based on students that had a sampling weight available from the public-use data file. Students were assessed in science achievement at third, fifth, and eighth grades and parents of the students were surveyed at the same time points. Analyses using latent growth curve modeling with time invariant and varying covariates in an SEM framework revealed a positive relationship between science achievement and parent involvement at eighth grade. Furthermore, there were gender and racial/ethnic differences in parents' school involvement as a predictor of science achievement. Findings indicated that students with lower initial science achievement scores had a faster rate of growth across time. The achievement gap between low and high achievers in earth, space and life sciences lessened from elementary to middle school. Parents' involvement with school usually tapers off after elementary school, but due to parent school involvement being a significant predictor of eighth grade science achievement, later school involvement may need to be supported and better implemented in secondary schooling.

  9. A Brief Review: The Z-curve Theory and its Application in Genome Analysis

    PubMed Central

    Zhang, Ren; Zhang, Chun-Ting

    2014-01-01

    In theoretical physics, there exist two basic mathematical approaches, algebraic and geometrical methods, which, in most cases, are complementary. In the area of genome sequence analysis, however, algebraic approaches have been widely used, while geometrical approaches have been less explored for a long time. The Z-curve theory is a geometrical approach to genome analysis. The Z-curve is a three-dimensional curve that represents a given DNA sequence in the sense that each can be uniquely reconstructed given the other. The Z-curve, therefore, contains all the information that the corresponding DNA sequence carries. The analysis of a DNA sequence can then be performed through studying the corresponding Z-curve. The Z-curve method has found applications in a wide range of areas in the past two decades, including the identifications of protein-coding genes, replication origins, horizontally-transferred genomic islands, promoters, translational start sides and isochores, as well as studies on phylogenetics, genome visualization and comparative genomics. Here, we review the progress of Z-curve studies from aspects of both theory and applications in genome analysis. PMID:24822026

  10. Princicpal Component Analysis of type II supernova V band light-curves

    NASA Astrophysics Data System (ADS)

    Galbany, Lluís

    2014-05-01

    We present a Principal Component Analysis (PCA) of the V band light-curves of a sample of more than 100 nearby Core collapse supernovae (CC SNe) from [Anderson et al. (2014)]. We used different reference epochs in order to extract the common properties of these light-curves and searched for correlations to some physical parameters such as the burning of 56Ni, and morphological light-curve parameters such as the length of the plateau, the stretch of the light-curve, and the decrements in brightness after maximum and after the plateau. We also used these similarities to create SNe II light-curve templates that will be used in the future for standardize these objects and determine cosmological distances.

  11. Trends in population mental health before and after the 2008 recession: a repeat cross-sectional analysis of the 1991–2010 Health Surveys of England

    PubMed Central

    Katikireddi, Srinivasa Vittal; Niedzwiedz, Claire L; Popham, Frank

    2012-01-01

    Objective To assess short-term differences in population mental health before and after the 2008 recession and explore how and why these changes differ by gender, age and socio-economic position. Design Repeat cross-sectional analysis of survey data. Setting England. Participants Representative samples of the working age (25–64 years) general population participating in the Health Survey for England between 1991 and 2010 inclusive. Main outcome measures Prevalence of poor mental health (caseness) as measured by the general health questionnaire-12 (GHQ). Results Age–sex standardised prevalence of GHQ caseness increased from 13.7% (95% CI 12.9% to 14.5%) in 2008 to 16.4% (95% CI 14.9% to 17.9%) in 2009 and 15.5% (95% CI 14.4% to 16.7%) in 2010. Women had a consistently greater prevalence since 1991 until the current recession. However, compared to 2008, men experienced an increase in age-adjusted caseness of 5.1% (95% CI 2.6% to 7.6%, p<0.001) in 2009 and 3% (95% CI 1.2% to 4.9%, p=0.001) in 2010, while no statistically significant changes were seen in women. Adjustment for differences in employment status and education level did not account for the observed increase in men nor did they explain the differential gender patterning. Over the last decade, socio-economic inequalities showed a tendency to increase but no clear evidence for an increase in inequalities associated with the recession was found. Similarly, no evidence was found for a differential effect between age groups. Conclusions Population mental health in men has deteriorated within 2 years of the onset of the current recession. These changes, and their patterning by gender, could not be accounted for by differences in employment status. Further work is needed to monitor recessionary impacts on health inequalities in response to ongoing labour market and social policy changes. PMID:23075569

  12. Obtaining DDF Curves of Extreme Rainfall Data Using Bivariate Copula and Frequency Analysis

    NASA Astrophysics Data System (ADS)

    Sadri, S.; Madsen, H.; Mikkelsen, P. S.; Burn, D. H.

    2009-05-01

    The traditional rainfall intensity-duration-frequency (IDF) curve is a reliable approach for representing the variation of rainfall intensity with duration for a given return period. In reality rainfall variables intensity, depth and duration are dependent and therefore a bivariate analysis using copulas can give a more accurate IDF curve. We study IDF curves using a copula in a bivariate frequency analysis of extreme rainfall. To be able to choose the most suitable copula among candidate copulas (i.e., Gumbel, Clayton, and Frank) we demonstrated IDF curves based on variation of depth with duration for a given return period and name them DDF (depth-duration-frequency) curves. The copula approach does not assume the rainfall variables are independent or jointly normally distributed. Rainfall series are extracted in three ways: (1) by maximum mean intensity; (2) by depth and duration of individual rainfall events; and (3) by storage volume and duration. In each case we used partial duration series (PDS) to extract extreme rainfall variables. The DDF curves derived from each method are presented and compared. This study examines extreme rainfall data from catchment Vedbæ k Renseanlæ g, situated near Copenhagen in Denmark. For rainfall extracted using method 2, the marginal distribution of depth was found to fit the Generalized Pareto distribution while duration was found to fit the Gamma distribution, using the method of L-moments. The volume was fit with a generalized Pareto distribution and the duration was fit with a Pearson type III distribution for rainfall extracted using method 3. The Clayton copula was found to be appropriate for bivariate analysis of rainfall depth and duration for both methods 2 and 3. DDF curves derived using the Clayton copula for depth and duration of individual rainfall events (method 2) are in agreement with empirically derived DDF curves obtained from maximum mean intensity (method 1) for a 10-year return period. For a 100-year return period the estimates differ by 2.5 cm for a 5 hr duration. This difference diminishes to almost zero for a 50 hr duration. If rainfall series are extracted by storage volume and duration (method 3), the difference between DDF curves derived from the Clayton copula and the empirical DDF curves are more appreciable and in general, DDF curves derived from method 3 show a smaller depth for the same duration for any selected return period. The differences between DDF curves illustrates that the method of extracting extreme rainfall as well as the frequency analysis approach have a considerable effect on the resulting DDF curves.

  13. New method for calculating a mathematical expression for streamflow recession

    USGS Publications Warehouse

    Rutledge, Albert T.

    1991-01-01

    An empirical method has been devised to calculate the master recession curve, which is a mathematical expression for streamflow recession during times of negligible direct runoff. The method is based on the assumption that the storage-delay factor, which is the time per log cycle of streamflow recession, varies linearly with the logarithm of streamflow. The resulting master recession curve can be nonlinear. The method can be executed by a computer program that reads a data file of daily mean streamflow, then allows the user to select several near-linear segments of streamflow recession. The storage-delay factor for each segment is one of the coefficients of the equation that results from linear least-squares regression. Using results for each recession segment, a mathematical expression of the storage-delay factor as a function of the log of streamflow is determined by linear least-squares regression. The master recession curve, which is a second-order polynomial expression for time as a function of log of streamflow, is then derived using the coefficients of this function.

  14. Etiology and occurrence of gingival recession - An epidemiological study

    PubMed Central

    Mythri, Sarpangala; Arunkumar, Suryanarayan Maiya; Hegde, Shashikanth; Rajesh, Shanker Kashyap; Munaz, Mohamed; Ashwin, Devasya

    2015-01-01

    Objectives: Gingival recession is the term used to characterize the apical shift of the marginal gingiva from its normal position on the crown of the tooth. It is frequently observed in adult subjects. The occurrence and severity of the gingival recession present considerable differences between populations. To prevent gingival recession from occurring, it is essential to detect the underlying etiology. The aim of the present study was to determine the occurrence of gingival recession and to identify the most common factor associated with the cause of gingival recession. Methods: A total of 710 subjects aged between 15 years to 60 years were selected. Data were collected by an interview with the help of a proforma and then the dental examination was carried out. The presence of gingival recession was recorded using Miller's classification of gingival recession. The Silness and Loe Plaque Index, Loe and Silness gingival index, community periodontal index were recorded. The data thus obtained were subjected to statistical analysis using Chi-square test and Student's unpaired t-test. Results: Of 710 subjects examined, 291 (40.98%) subjects exhibited gingival recession. The frequency of gingival recession was found to increase with age. High frequency of gingival recession was seen in males (60.5%) compared to females (39.5%). Gingival recession was commonly seen in mandibular incisors (43.0%). Miller's class I gingival recession was more commonly seen. The most common cause for gingival recession was dental plaque accumulation (44.1%) followed by faulty toothbrushing (42.7%). Conclusion: Approximately half of the subjects examined exhibited gingival recession. The etiology of gingival recession is multifactorial, and its appearance is always the result of more than one factor acting together.

  15. Evaluating the influence of watershed moisture storage on variations in base flow recession rates during prolonged rain-free periods in medium-sized catchments in New York and Illinois, USA

    NASA Astrophysics Data System (ADS)

    Shaw, Stephen B.; McHardy, Theodore M.; Riha, Susan J.

    2013-09-01

    When dQ/dt-Q plots of stream recession are constructed for individual recession events, the slopes of the dQ/dt-Q curves are near constant in log space, but the intercepts vary seasonally. Because the intercepts increase during the summer (indicating an increase in the recession rate at a given discharge), it has often been assumed that increased evapotranspiration (ET) leads to increased recession rates. To test this assumption, we related the intercepts of dQ/dt-Q curves from 72 recession events to the concurrent ET and watershed moisture storage as determined from the National Center for Environmental Prediction (NCEP) North American Regional Reanalysis (NARR) data set. The analysis suggests that at least for the nine watersheds from Illinois and New York we studied, shifts in recession rate during prolonged rain-free periods had little linkage to concurrent ET. Instead, we observe that the shifting has a moderately strong linkage to watershed moisture storage during the recession event. While this seeming lack of dependence on ET during these prolonged rain-free periods is not necessarily reflective of more normal conditions, we suggest it provides some insight into underlying subsurface controls at the watershed scale. In particular, we hypothesize that the shift in intercept in dQ/dt-Q curves results from spatial heterogeneities in watershed surficial geology; under dryer conditions near-stream subsurface zones with high hydraulic conductivities contribute most streamflow but under wetter conditions subsurface zones in upland areas with lower hydraulic conductivities also contribute.

  16. Analysis and Design of Stimulus Response Curves of E. coli

    PubMed Central

    Kremling, Andreas; Goehler, Anna; Jahreis, Knut; Nees, Markus; Auerbach, Benedikt; Schmidt-Heck, Wolfgang; Kökpinar, Öznur; Geffers, Robert; Rinas, Ursula; Bettenbrock, Katja

    2012-01-01

    Metabolism and signalling are tightly coupled in bacteria. Combining several theoretical approaches, a core model is presented that describes transcriptional and allosteric control of glycolysis in Escherichia coli. Experimental data based on microarrays, signaling components and extracellular metabolites are used to estimate kinetic parameters. A newly designed strain was used that adjusts the incoming glucose flux into the system and allows a kinetic analysis. Based on the results, prediction for intracelluar metabolite concentrations over a broad range of the growth rate could be performed and compared with data from literature. PMID:24957765

  17. A Fourier method for the analysis of exponential decay curves.

    PubMed

    Provencher, S W

    1976-01-01

    A method based on the Fourier convolution theorem is developed for the analysis of data composed of random noise, plus an unknown constant "base line," plus a sum of (or an integral over a continuous spectrum of) exponential decay functions. The Fourier method's usual serious practical limitation of needing high accuracy data over a very wide range is eliminated by the introduction of convergence parameters and a Gaussian taper window. A computer program is described for the analysis of discrete spectra, where the data involves only a sum of exponentials. The program is completely automatic in that the only necessary inputs are the raw data (not necessarily in equal intervals of time); no potentially biased initial guesses concerning either the number or the values of the components are needed. The outputs include the number of components, the amplitudes and time constants together with their estimated errors, and a spectral plot of the solution. The limiting resolving power of the method is studied by analyzing a wide range of simulated two-, three-, and four-component data. The results seem to indicate that the method is applicable over a considerably wider range of conditions than nonlinear least squares or the method of moments. PMID:1244888

  18. A light-curve distortion-wave analysis of eight RS Canum Venaticorum systems

    NASA Astrophysics Data System (ADS)

    Caton, D. B.

    1986-01-01

    A program of differential U,B,V photometry of 14 RS CVn systems carried out at Rosemary Hill Observatory in 1978 - 1981 is described, and an analysis of the light curves for the characteristic distortion wave for eight of the systems is presented. The V light curves of the systems are shown. Significant waves were observed in RS CVn, RZ Eri, and RW UMa. No significant waves were found in UX Com, GK Hya, AR Lac, LX Per, or TY Pyx. Unusual light curve distortions were observed in UX Com and AR Lac.

  19. WTF- and A- Stars: Spectroscopic Analysis of Kepler Light Curves

    NASA Astrophysics Data System (ADS)

    Grae Short, Miona; Soderblom, David R.

    2016-01-01

    Analysis of Kepler data in 2012 found that in a sample of about 2000 A- and F- stars, 1% of them seemed to exhibit white light flares. However, such stars are not thought to have the convective envelopes needed to produce the magnetic dynamos that yield flares. We use the same Kepler data but examine the flaring stars more comprehensively by analyzing the pixel data in order to predict whether this flare-like behavior may be caused by smaller, less luminous M dwarfs exhibiting genuine flares in the line of sight of the A- and F-stars. The implications of finding verifiable flare activity in a subset of these stars would be enough to incite further investigation of the physical processes that allow this to take place. Yet, if that were not the case, this project would further be able to demonstrate the steps necessary to correct for false-positives in finding flares in A- and F- stars.

  20. The Recess Renaissance

    ERIC Educational Resources Information Center

    Keeler, Rusty

    2015-01-01

    The author tells of his work around the country and world on transforming how schools do recess, free play, and outside time by transforming their outdoor spaces to match. Instead of a playground of fixed structures like traditional school grounds, newer spaces are filled with loose materials that children can use to build forts, dens, and tree

  1. The Recess Renaissance

    ERIC Educational Resources Information Center

    Keeler, Rusty

    2015-01-01

    The author tells of his work around the country and world on transforming how schools do recess, free play, and outside time by transforming their outdoor spaces to match. Instead of a playground of fixed structures like traditional school grounds, newer spaces are filled with loose materials that children can use to build forts, dens, and tree…

  2. Analysis and Simulation of Long-Range Correlations in Curved Space

    NASA Astrophysics Data System (ADS)

    Mehrabi, Ali Reza; Sahimi, Muhammad

    Numerical simulation and analysis of long-range correlations in curved space are studied. The study is motivated by the problem of constructing accurate models of large-scale porous media which usually contain long-range correlations in their various properties (such as their permeability, porosity, and elastic moduli) within and between their strata that are typically curved layers. The problem is, however, relevant to many other important models and phenomena in which extended correlations in curved space play a prominent role. Examples include the nonlinear σ-model in a curved space, models for describing the long-range structural correlations of amorphous semiconductors that consist of polytopes (tilings of positively-curved three-dimensional space), long-range correlations in the extrapolar total zone, and models in which the Universe is created by bubble nucleations and contain long-range correlations in the fluctuations in the curved spacetime. The study is also relevant to the important industrial problem of designing highly curved objects, such as cars and ships, which use composite materials that contain extended correlations in their property values. We study such correlations along two- and three-dimensional curves, as well as curved surfaces. We show that such correlations are well-defined only on developable surfaces, i.e. those that can be flattened to form planar surfaces without any stretching or distortion, and preserve the distance between two points on such surfaces after the stretching. If a given curved surface is not developable, but can be approximated as piecewise developable, one may still define and analyze extended correlations on it. Representative examples are presented and analyzed.

  3. TYPE Ia SUPERNOVA LIGHT-CURVE INFERENCE: HIERARCHICAL BAYESIAN ANALYSIS IN THE NEAR-INFRARED

    SciTech Connect

    Mandel, Kaisey S.; Friedman, Andrew S.; Kirshner, Robert P.; Wood-Vasey, W. Michael

    2009-10-10

    We present a comprehensive statistical analysis of the properties of Type Ia supernova (SN Ia) light curves in the near-infrared using recent data from Peters Automated InfraRed Imaging TELescope and the literature. We construct a hierarchical Bayesian framework, incorporating several uncertainties including photometric error, peculiar velocities, dust extinction, and intrinsic variations, for principled and coherent statistical inference. SN Ia light-curve inferences are drawn from the global posterior probability of parameters describing both individual supernovae and the population conditioned on the entire SN Ia NIR data set. The logical structure of the hierarchical model is represented by a directed acyclic graph. Fully Bayesian analysis of the model and data is enabled by an efficient Markov Chain Monte Carlo algorithm exploiting the conditional probabilistic structure using Gibbs sampling. We apply this framework to the JHK{sub s} SN Ia light-curve data. A new light-curve model captures the observed J-band light-curve shape variations. The marginal intrinsic variances in peak absolute magnitudes are sigma(M{sub J}) = 0.17 +- 0.03, sigma(M{sub H}) = 0.11 +- 0.03, and sigma(M{sub Ks}) = 0.19 +- 0.04. We describe the first quantitative evidence for correlations between the NIR absolute magnitudes and J-band light-curve shapes, and demonstrate their utility for distance estimation. The average residual in the Hubble diagram for the training set SNe at cz > 2000kms{sup -1} is 0.10 mag. The new application of bootstrap cross-validation to SN Ia light-curve inference tests the sensitivity of the statistical model fit to the finite sample and estimates the prediction error at 0.15 mag. These results demonstrate that SN Ia NIR light curves are as effective as corrected optical light curves, and, because they are less vulnerable to dust absorption, they have great potential as precise and accurate cosmological distance indicators.

  4. Development of synthetic flood damage curve by explicit costs analysis

    NASA Astrophysics Data System (ADS)

    Martina, Mario; Molinari, Daniela; Dottori, Francesco; Scorzini, Annarita

    2015-04-01

    Damage modelling is a key component in flood risk assessments. A conventional approach for estimating direct flood damages is the use of depth-damage functions. However, at present, there are few studies that describe in detail the parameters involved in the models and the hypotheses used for the development of these functions based on synthetic approaches and/or actual flood damage data. In this work a synthetic approach was adopted for the development of a damage model for residential buildings. The approach follows the loss assessment procedure usually applied by the insurance loss adjusters. Required information consisted of all those variables that are necessary to define hazard characteristics at building location, compute the exposure value of the building and the replacement costs of its components. In detail, the model requires four input tables. The hazard module includes the variables describing the features of the flood event at building location (e.g. water depth outside the building, water depth inside the basement, maximum velocity of the flood, duration of the event, contaminant and sediment load). The exposure module includes both extensive variables (e.g. foot print area, number of floors) and "vulnerability" variables, where the latter affect damage estimation in two different ways: by changing the replacement value/unit prices of the building and its components (e.g. the finishing level, building type) or by modifying the function(s) describing damage mechanisms (e.g. building structure, plant distribution). The replacement values table and the unit-price table include respectively the replacement value of the building and the unitary replacement costs of the different building components (e.g. doors and pavement replacement per square meter). The final output of the model is represented by different sets of damage functions describing all the building components (e.g. plasters, plants), depending on hazard, exposure and vulnerability characteristics. Such functions were developed using a what-if analysis using data collected after the 2012 flood in the Umbria Region in Central Italy, as well as authors' experience, as reference to understand damage mechanisms. Observed damage data were also used to calibrate the functions.

  5. A new methodology for free wake analysis using curved vortex elements

    NASA Technical Reports Server (NTRS)

    Bliss, Donald B.; Teske, Milton E.; Quackenbush, Todd R.

    1987-01-01

    A method using curved vortex elements was developed for helicopter rotor free wake calculations. The Basic Curve Vortex Element (BCVE) is derived from the approximate Biot-Savart integration for a parabolic arc filament. When used in conjunction with a scheme to fit the elements along a vortex filament contour, this method has a significant advantage in overall accuracy and efficiency when compared to the traditional straight-line element approach. A theoretical and numerical analysis shows that free wake flows involving close interactions between filaments should utilize curved vortex elements in order to guarantee a consistent level of accuracy. The curved element method was implemented into a forward flight free wake analysis, featuring an adaptive far wake model that utilizes free wake information to extend the vortex filaments beyond the free wake regions. The curved vortex element free wake, coupled with this far wake model, exhibited rapid convergence, even in regions where the free wake and far wake turns are interlaced. Sample calculations are presented for tip vortex motion at various advance ratios for single and multiple blade rotors. Cross-flow plots reveal that the overall downstream wake flow resembles a trailing vortex pair. A preliminary assessment shows that the rotor downwash field is insensitive to element size, even for relatively large curved elements.

  6. Light curve morphology analysis of contact binaries observed with the Kepler satellite

    NASA Astrophysics Data System (ADS)

    Debski, Bartłomiej; Zoła, Stanisław

    2014-09-01

    Light-curve morphology analysis of contact binaries provides model-independent insight into the short-term evolution of the system activity. Light-curve morphology applied to the Kepler data of contact binaries reveals directly the migration spot connection to the light curve's intrinsic rapid changes. Since the flat-bottom secondary minima cannot be studied in the way Tran et al. (2013) or Conroy et al. (2014) did, we measure the actual light-curve minimum, instead of the presumed mid-eclipse time. This, combined with the study of the minimum depth, allowed us to uncover the direction of the spot migration for particular binaries. At the same time, the O'Connell effect evolution and the maxima separation confronted with modeling based on the Wilson-Devinney code agree with polar dark spots. The combined results of this new approach offer constraints on the star spots size, temperature and latitude at high precision.

  7. Numerical analysis of curved frequency selective surface by finite-difference time-domain

    NASA Astrophysics Data System (ADS)

    Chen, Xin-yi; Wang, Jian-bo; Chen, Gui-bo; Sun, Guan-cheng; Lu, Jun

    2011-08-01

    Frequency selective surface is a monolayer or multilayer 2D periodic structure which is composed of multiple resonance units scattering by a two-dimensional periodic array on dielectric layer. FSS can't absorb radio frequency energy, but can filter the frequency which is therefore applied in microwave technique or stealth technology. The relative research on curved FSS is relatively scarce since the curved FSS structure can be obtained only when FSS is attached on the materials surfaces of curved structures in engineering application. However, curved FSS is widely applied in practical engineering; therefore, the research on curved FSS structure has important significance. In this paper, a curved FSS structure model of Y-pore unit is established and numerical simulated by means of FDTD. The influence of curvature on FSS transmission characteristics is studied according to the analysis on the changing of radar cross section (RCS). The results show: the center frequency point of the plane band pass FSS structure drifts after the curve surface deformation of the structure; the center frequency point of the curved band pass FSS structure drifts with the changing of the curvature radius, i. e. with the decreasing of curvature radius, the frequency point drifts towards high points and the transmittance decreases. The design of FSS radome demands of accurate and stable center resonance frequency; therefore, the actual situation of curved surface should be considered in practical engineering application when band pass FSS is made into frequency selection filtering radome. The curvature radius should be long enough to avoid center frequency drifting and transmittance deceasing.

  8. A general geomorphological recession flow model for river basins

    NASA Astrophysics Data System (ADS)

    Biswal, Basudev; Nagesh Kumar, D.

    2013-08-01

    Recession flows in a basin are controlled by the temporal evolution of its active drainage network (ADN). The geomorphological recession flow model (GRFM) assumes that both the rate of flow generation per unit ADN length (q) and the speed at which ADN heads move downstream (c) remain constant during a recession event. Thereby, it connects the power law exponent of -dQ/dt versus Q (discharge at the outlet at time t) curve, α, with the structure of the drainage network, a fixed entity. In this study, we first reformulate the GRFM for Horton-Strahler networks and show that the geomorphic α (αg) is equal to D/>(D-1>), where D is the fractal dimension of the drainage network. We then propose a more general recession flow model by expressing both q and c as functions of Horton-Strahler stream order. We show that it is possible to have α =α g for a recession event even when q and c do not remain constant. The modified GRFM suggests that α is controlled by the spatial distribution of subsurface storage within the basin. By analyzing streamflow data from 39 U.S. Geological Survey basins, we show that α is having a power law relationship with recession curve peak, which indicates that the spatial distribution of subsurface storage varies across recession events.

  9. Specific yield as determined by type-curve analysis of aquifer-test data

    USGS Publications Warehouse

    Moench, Allen F.

    1994-01-01

    The commonly used analytical solution developed by Neuman for a homogeneous, water-table aquifer assumes that the drainage of pores in the zone above the water table due to lowering of the water table occurs instantaneously. Noninstantaneous drainage of pores in the unsaturated zone accounts for the finding that both type-curve analysis and volume-balance calculations yield values of specific yield that are slightly less than those obtained from laboratory column-drainage experiments. It may also account for a slight underestimation of vertical hydraulic conductivity as obtained by type-curve analysis.

  10. AtomicJ: an open source software for analysis of force curves.

    PubMed

    Hermanowicz, Paweł; Sarna, Michał; Burda, Kvetoslava; Gabryś, Halina

    2014-06-01

    We present an open source Java application for analysis of force curves and images recorded with the Atomic Force Microscope. AtomicJ supports a wide range of contact mechanics models and implements procedures that reduce the influence of deviations from the contact model. It generates maps of mechanical properties, including maps of Young's modulus, adhesion force, and sample height. It can also calculate stacks, which reveal how sample's response to deformation changes with indentation depth. AtomicJ analyzes force curves concurrently on multiple threads, which allows for high speed of analysis. It runs on all popular operating systems, including Windows, Linux, and Macintosh. PMID:24985823

  11. AtomicJ: An open source software for analysis of force curves

    SciTech Connect

    Hermanowicz, Paweł Gabryś, Halina; Sarna, Michał; Burda, Kvetoslava

    2014-06-15

    We present an open source Java application for analysis of force curves and images recorded with the Atomic Force Microscope. AtomicJ supports a wide range of contact mechanics models and implements procedures that reduce the influence of deviations from the contact model. It generates maps of mechanical properties, including maps of Young's modulus, adhesion force, and sample height. It can also calculate stacks, which reveal how sample's response to deformation changes with indentation depth. AtomicJ analyzes force curves concurrently on multiple threads, which allows for high speed of analysis. It runs on all popular operating systems, including Windows, Linux, and Macintosh.

  12. AtomicJ: An open source software for analysis of force curves

    NASA Astrophysics Data System (ADS)

    Hermanowicz, Paweł; Sarna, Michał; Burda, Kvetoslava; Gabryś, Halina

    2014-06-01

    We present an open source Java application for analysis of force curves and images recorded with the Atomic Force Microscope. AtomicJ supports a wide range of contact mechanics models and implements procedures that reduce the influence of deviations from the contact model. It generates maps of mechanical properties, including maps of Young's modulus, adhesion force, and sample height. It can also calculate stacks, which reveal how sample's response to deformation changes with indentation depth. AtomicJ analyzes force curves concurrently on multiple threads, which allows for high speed of analysis. It runs on all popular operating systems, including Windows, Linux, and Macintosh.

  13. Retrospective North American CFL Experience Curve Analysis and Correlation to Deployment Programs

    SciTech Connect

    Smith, Sarah J.; Wei, Max; Sohn, Michael D.

    2015-07-01

    Retrospective experience curves are a useful tool for understanding historic technology development, and can contribute to investment program analysis and future cost estimation efforts. This work documents our development of an analysis approach for deriving retrospective experience curves with a variable learning rate, and its application to develop an experience curve for compact fluorescent lamps for the global and North American markets over the years 1990-2007. Uncertainties and assumptions involved in interpreting data for our experience curve development are discussed, including the processing and transformation of empirical data, the selection of system boundaries, and the identification of historical changes in the learning rate over the course of 15 years. In the results that follow, we find that that the learning rate has changed at least once from 1990-2007. We also explore if, and to what degree, public deployment programs may have contributed to an increased technology learning rate in North America. We observe correlations between the changes in the learning rate and the initiation of new policies, abrupt technological advances, including improvements to ballast technology, and economic and political events such as trade tariffs and electricity prices. Finally, we discuss how the findings of this work (1) support the use of segmented experience curves for retrospective and prospective analysis and (2) may imply that investments in technological research and development have contributed to a change in market adoption and penetration.

  14. Testing and analysis of flat and curved panels with multiple cracks

    NASA Technical Reports Server (NTRS)

    Broek, David; Jeong, David Y.; Thomson, Douglas

    1994-01-01

    An experimental and analytical investigation of multiple cracking in various types of test specimens is described in this paper. The testing phase is comprised of a flat unstiffened panel series and curved stiffened and unstiffened panel series. The test specimens contained various configurations for initial damage. Static loading was applied to these specimens until ultimate failure, while loads and crack propagation were recorded. This data provides the basis for developing and validating methodologies for predicting linkup of multiple cracks, progression to failure, and overall residual strength. The results from twelve flat coupon and ten full scale curved panel tests are presented. In addition, an engineering analysis procedure was developed to predict multiple crack linkup. Reasonable agreement was found between predictions and actual test results for linkup and residual strength for both flat and curved panels. The results indicate that an engineering analysis approach has the potential to quantitatively assess the effect of multiple cracks in the arrest capability of an aircraft fuselage structure.

  15. Drainage-system development in consecutive melt seasons at a polythermal, Arctic glacier, evaluated by flow-recession analysis and linear-reservoir simulation

    PubMed Central

    Hodgkins, Richard; Cooper, Richard; Tranter, Martyn; Wadham, Jemma

    2013-01-01

    [1] The drainage systems of polythermal glaciers play an important role in high-latitude hydrology, and are determinants of ice flow rate. Flow-recession analysis and linear-reservoir simulation of runoff time series are here used to evaluate seasonal and inter-annual variability in the drainage system of the polythermal Finsterwalderbreen, Svalbard, in 1999 and 2000. Linear-flow recessions are pervasive, with mean coefficients of a fast reservoir varying from 16 (1999) to 41 h (2000), and mean coefficients of an intermittent, slow reservoir varying from 54 (1999) to 114 h (2000). Drainage-system efficiency is greater overall in the first of the two seasons, the simplest explanation of which is more rapid depletion of the snow cover. Reservoir coefficients generally decline during each season (at 0.22 h d−1 in 1999 and 0.52 h d−1 in 2000), denoting an increase in drainage efficiency. However, coefficients do not exhibit a consistent relationship with discharge. Finsterwalderbreen therefore appears to behave as an intermediate case between temperate glaciers and other polythermal glaciers with smaller proportions of temperate ice. Linear-reservoir runoff simulations exhibit limited sensitivity to a relatively wide range of reservoir coefficients, although the use of fixed coefficients in a spatially lumped model can generate significant subseasonal error. At Finsterwalderbreen, an ice-marginal channel with the characteristics of a fast reservoir, and a subglacial upwelling with the characteristics of a slow reservoir, both route meltwater to the terminus. This suggests that drainage-system components of significantly contrasting efficiencies can coexist spatially and temporally at polythermal glaciers. PMID:25598557

  16. Soil hydraulic properties estimate based on numerical analysis of disc infiltrometer three-dimensional infiltration curve

    NASA Astrophysics Data System (ADS)

    Latorre, Borja; Peña-Sancho, Carolina; Angulo-Jaramillo, Rafaël; Moret-Fernández, David

    2015-04-01

    Measurement of soil hydraulic properties is of paramount importance in fields such as agronomy, hydrology or soil science. Fundamented on the analysis of the Haverkamp et al. (1994) model, the aim of this paper is to explain a technique to estimate the soil hydraulic properties (sorptivity, S, and hydraulic conductivity, K) from the full-time cumulative infiltration curves. The method (NSH) was validated by means of 12 synthetic infiltration curves generated with HYDRUS-3D from known soil hydraulic properties. The K values used to simulate the synthetic curves were compared to those estimated with the proposed method. A procedure to identify and remove the effect of the contact sand layer on the cumulative infiltration curve was also developed. A sensitivity analysis was performed using the water level measurement as uncertainty source. Finally, the procedure was evaluated using different infiltration times and data noise. Since a good correlation between the K used in HYDRUS-3D to model the infiltration curves and those estimated by the NSH method was obtained, (R2 =0.98), it can be concluded that this technique is robust enough to estimate the soil hydraulic conductivity from complete infiltration curves. The numerical procedure to detect and remove the influence of the contact sand layer on the K and S estimates seemed to be robust and efficient. An effect of the curve infiltration noise on the K estimate was observed, which uncertainty increased with increasing noise. Finally, the results showed that infiltration time was an important factor to estimate K. Lower values of K or smaller uncertainty needed longer infiltration times.

  17. A Latent Growth Curve Analysis of Reading Achievement for an At-Risk Population

    ERIC Educational Resources Information Center

    Beecher, Constance C.

    2011-01-01

    The development of reading skills from age seven until age 19 was investigated for children who were referred for special education preschool intervention using latent growth curve analysis (n=206). Approximately one-third of the study sample did not require special education services after preschool, providing a natural comparison group. Reading…

  18. Computational Tools for Probing Interactions in Multiple Linear Regression, Multilevel Modeling, and Latent Curve Analysis

    ERIC Educational Resources Information Center

    Preacher, Kristopher J.; Curran, Patrick J.; Bauer, Daniel J.

    2006-01-01

    Simple slopes, regions of significance, and confidence bands are commonly used to evaluate interactions in multiple linear regression (MLR) models, and the use of these techniques has recently been extended to multilevel or hierarchical linear modeling (HLM) and latent curve analysis (LCA). However, conducting these tests and plotting the

  19. Aptitude-Treatment Interaction Effects on Explicit Rule Learning: A Latent Growth Curve Analysis

    ERIC Educational Resources Information Center

    Hwu, Fenfang; Pan, Wei; Sun, Shuyan

    2014-01-01

    Finding the match between individuals and educational treatments is the aim of both educators and the aptitude-treatment interaction research paradigm. Using the latent growth curve analysis, the present study investigates the interaction between the type of explicit instructional approaches (deductive vs. explicit-inductive) and the level of

  20. Taxometrics, Polytomous Constructs, and the Comparison Curve Fit Index: A Monte Carlo Analysis

    ERIC Educational Resources Information Center

    Walters, Glenn D.; McGrath, Robert E.; Knight, Raymond A.

    2010-01-01

    The taxometric method effectively distinguishes between dimensional (1-class) and taxonic (2-class) latent structure, but there is virtually no information on how it responds to polytomous (3-class) latent structure. A Monte Carlo analysis showed that the mean comparison curve fit index (CCFI; Ruscio, Haslam, & Ruscio, 2006) obtained with 3…

  1. Aptitude-Treatment Interaction Effects on Explicit Rule Learning: A Latent Growth Curve Analysis

    ERIC Educational Resources Information Center

    Hwu, Fenfang; Pan, Wei; Sun, Shuyan

    2014-01-01

    Finding the match between individuals and educational treatments is the aim of both educators and the aptitude-treatment interaction research paradigm. Using the latent growth curve analysis, the present study investigates the interaction between the type of explicit instructional approaches (deductive vs. explicit-inductive) and the level of…

  2. Policy Effectiveness and the Slopes of IS and LM Curves: A Graphical Analysis.

    ERIC Educational Resources Information Center

    Revier, Charles F.

    2000-01-01

    Focuses on the IS-LM model providing a graphical analysis designed to clarify the confusion induced by misleading statements in several major macroeconomics textbooks concerning the connection between policy effectiveness and the slopes of the IS and LM curves. Includes references. (CMK)

  3. Progress curve analysis of qRT-PCR reactions using the logistic growth equation.

    PubMed

    Liu, Meile; Udhe-Stone, Claudia; Goudar, Chetan T

    2011-01-01

    We present an alternate approach for analyzing data from real-time reverse transcription polymerase chain reaction (qRT-PCR) experiments by fitting individual fluorescence vs. cycle number (F vs. C) curves to the logistic growth equation. The best fit parameters determined by nonlinear least squares were used to compute the second derivative of the logistic equation and the cycle threshold, C(t), was determined from the maximum value of the second derivative. This C(t) value was subsequently used to determine ΔΔC(t) and the amplification efficiency, E(n), thereby completing the analysis on a qRT-PCR data set. The robustness of the logistic approach was verified by testing ~600 F vs. C curves using both new and previously published data sets. In most cases, comparisons were made between the logistic estimates and those from the standard curve and comparative C(t) methods. Deviations between the logistic and standard curve method ranged between 3-10% for C(t) estimates, 2-10% for ΔΔC(t) estimates, and 1-11% for E(n) estimates. The correlations between C(t) estimates from the logistic and standard curve methods were very high, often >0.95. When compared with five other established methods of qRT-PCR data analysis to predict initial concentrations of two genes encompassing a total of 500 F vs. C curves, the logistic estimates were of comparable accuracy. This reliable performance of the logistic approach comes without the need to construct standard curves which can be a laborious undertaking. Also, no a priori assumptions for E(n) are necessary while some other methods assume equal E(n) values for the reference and target genes, an assumption that is not universally valid. In addition, by accurately describing the data in the plateau region of the F vs. C curve, the logistic method overcomes the limitations of the sigmoidal curve fitting method. The streamlined nature of the logistic approach makes it ideal for complete automation on a variety of computing environments thereby completely eliminating user bias. The simplicity, robustness, and ease of computer implementation of the logistic approach should make it an attractive alternative for rapidly analyzing qRT-PCR data. PMID:21766473

  4. Shape information from glucose curves: Functional data analysis compared with traditional summary measures

    PubMed Central

    2013-01-01

    Background Plasma glucose levels are important measures in medical care and research, and are often obtained from oral glucose tolerance tests (OGTT) with repeated measurements over 2–3 hours. It is common practice to use simple summary measures of OGTT curves. However, different OGTT curves can yield similar summary measures, and information of physiological or clinical interest may be lost. Our mean aim was to extract information inherent in the shape of OGTT glucose curves, compare it with the information from simple summary measures, and explore the clinical usefulness of such information. Methods OGTTs with five glucose measurements over two hours were recorded for 974 healthy pregnant women in their first trimester. For each woman, the five measurements were transformed into smooth OGTT glucose curves by functional data analysis (FDA), a collection of statistical methods developed specifically to analyse curve data. The essential modes of temporal variation between OGTT glucose curves were extracted by functional principal component analysis. The resultant functional principal component (FPC) scores were compared with commonly used simple summary measures: fasting and two-hour (2-h) values, area under the curve (AUC) and simple shape index (2-h minus 90-min values, or 90-min minus 60-min values). Clinical usefulness of FDA was explored by regression analyses of glucose tolerance later in pregnancy. Results Over 99% of the variation between individually fitted curves was expressed in the first three FPCs, interpreted physiologically as “general level” (FPC1), “time to peak” (FPC2) and “oscillations” (FPC3). FPC1 scores correlated strongly with AUC (r=0.999), but less with the other simple summary measures (−0.42≤r≤0.79). FPC2 scores gave shape information not captured by simple summary measures (−0.12≤r≤0.40). FPC2 scores, but not FPC1 nor the simple summary measures, discriminated between women who did and did not develop gestational diabetes later in pregnancy. Conclusions FDA of OGTT glucose curves in early pregnancy extracted shape information that was not identified by commonly used simple summary measures. This information discriminated between women with and without gestational diabetes later in pregnancy. PMID:23327294

  5. Effects of variable recruitment on catch-curve analysis for crappie populations

    USGS Publications Warehouse

    Allen, M.S.

    1997-01-01

    Catch-curve analysis is frequently used to estimate total annual mortality (A) of exploited fishes, but the method assumes constant recruitment. Because populations of crappie Pomoxis spp. have exhibited large fluctuations in recruitment, I conducted simulations to assess the amount of variability in recruitment that precludes the use of a catch curve and compared results to recruitment dynamics in six crappie populations. Coefficients of variation (CV = 100 ?? SD/mean) in recruitment to age 1 ranged from 55% to 84% among the six crappie populations. Simulations suggested that recruitment variability in these ranges would likely allow estimation of A within ?? 10%, but the probability of obtaining estimates of A that were ??5% or more of the true A would exceed 0.15. I suggest that catch curves may be used to approximate A in crappie populations but that managers should consider the effects on management recommendations if A were ??10% of the estimated A.

  6. Learning Factors Transfer Analysis: Using Learning Curve Analysis to Automatically Generate Domain Models

    ERIC Educational Resources Information Center

    Pavlik, Philip I. Jr.; Cen, Hao; Koedinger, Kenneth R.

    2009-01-01

    This paper describes a novel method to create a quantitative model of an educational content domain of related practice item-types using learning curves. By using a pairwise test to search for the relationships between learning curves for these item-types, we show how the test results in a set of pairwise transfer relationships that can be…

  7. A computational model-based validation of Guyton's analysis of cardiac output and venous return curves

    NASA Technical Reports Server (NTRS)

    Mukkamala, R.; Cohen, R. J.; Mark, R. G.

    2002-01-01

    Guyton developed a popular approach for understanding the factors responsible for cardiac output (CO) regulation in which 1) the heart-lung unit and systemic circulation are independently characterized via CO and venous return (VR) curves, and 2) average CO and right atrial pressure (RAP) of the intact circulation are predicted by graphically intersecting the curves. However, this approach is virtually impossible to verify experimentally. We theoretically evaluated the approach with respect to a nonlinear, computational model of the pulsatile heart and circulation. We developed two sets of open circulation models to generate CO and VR curves, differing by the manner in which average RAP was varied. One set applied constant RAPs, while the other set applied pulsatile RAPs. Accurate prediction of intact, average CO and RAP was achieved only by intersecting the CO and VR curves generated with pulsatile RAPs because of the pulsatility and nonlinearity (e.g., systemic venous collapse) of the intact model. The CO and VR curves generated with pulsatile RAPs were also practically independent. This theoretical study therefore supports the validity of Guyton's graphical analysis.

  8. Complexity analysis of the temperature curve: new information from body temperature.

    PubMed

    Varela, Manuel; Jimenez, Leticia; Fariña, Rosa

    2003-05-01

    An attempt was made to develop a truly quantitative approach to temperature, based on models derived from nonlinear dynamics and chaos theory. Three different procedures for measuring the degree of complexity of the temperature curve were compared, and the possible correlations between these measurements and certain physiopathologically relevant parameters in healthy subjects were examined. Twenty-three healthy subjects (10 males, 13 females) between 18 and 85 years of age had their temperature measured every 10 min for at least 30 h. These time series were used to determine the approximate entropy (ApEn), a detrended fluctuation analysis (DFA), and the fractal dimension by the compass method (FD(c)). There was good correlation between the different methods of measuring the complexity of the curve [ r=-0.603 for ApEn vs. DFA ( p=0.002), r=0.438 for ApEn vs. FDc ( p=0.04) and r=-0.647 for DFA vs. FDc ( p=0.0008)]. Both the fractal dimension and the approximate entropy were inversely correlated with age [ r=-0.637 ( p=0.001) and r=-0.417 ( p=0.03), respectively], while the DFA increased with age ( r=0.413, p=0.04). The results thus suggest that complexity of the temperature curve decreases with age. The complexity of the temperature curve can be quantified in a consistent fashion. Age is associated with lower complexity of the temperature curve. PMID:12736830

  9. Analytical Problems and Suggestions in the Analysis of Behavioral Economic Demand Curves.

    PubMed

    Yu, Jihnhee; Liu, Liu; Collins, R Lorraine; Vincent, Paula C; Epstein, Leonard H

    2014-01-01

    Behavioral economic demand curves (Hursh, Raslear, Shurtleff, Bauman, & Simmons, 1988) are innovative approaches to characterize the relationships between consumption of a substance and its price. In this article, we investigate common analytical issues in the use of behavioral economic demand curves, which can cause inconsistent interpretations of demand curves, and then we provide methodological suggestions to address those analytical issues. We first demonstrate that log transformation with different added values for handling zeros changes model parameter estimates dramatically. Second, demand curves are often analyzed using an overparameterized model that results in an inefficient use of the available data and a lack of assessment of the variability among individuals. To address these issues, we apply a nonlinear mixed effects model based on multivariate error structures that has not been used previously to analyze behavioral economic demand curves in the literature. We also propose analytical formulas for the relevant standard errors of derived values such as P max, O max, and elasticity. The proposed model stabilizes the derived values regardless of using different added increments and provides substantially smaller standard errors. We illustrate the data analysis procedure using data from a relative reinforcement efficacy study of simulated marijuana purchasing. PMID:26741176

  10. The analysis of dose-response curve from bioassays with quantal response: Deterministic or statistical approaches?

    PubMed

    Mougabure-Cueto, G; Sfara, V

    2016-04-25

    Dose-response relations can be obtained from systems at any structural level of biological matter, from the molecular to the organismic level. There are two types of approaches for analyzing dose-response curves: a deterministic approach, based on the law of mass action, and a statistical approach, based on the assumed probabilities distribution of phenotypic characters. Models based on the law of mass action have been proposed to analyze dose-response relations across the entire range of biological systems. The purpose of this paper is to discuss the principles that determine the dose-response relations. Dose-response curves of simple systems are the result of chemical interactions between reacting molecules, and therefore are supported by the law of mass action. In consequence, the shape of these curves is perfectly sustained by physicochemical features. However, dose-response curves of bioassays with quantal response are not explained by the simple collision of molecules but by phenotypic variations among individuals and can be interpreted as individual tolerances. The expression of tolerance is the result of many genetic and environmental factors and thus can be considered a random variable. In consequence, the shape of its associated dose-response curve has no physicochemical bearings; instead, they are originated from random biological variations. Due to the randomness of tolerance there is no reason to use deterministic equations for its analysis; on the contrary, statistical models are the appropriate tools for analyzing these dose-response relations. PMID:26952004

  11. ATWS Analysis with an Advanced Boiling Curve Approach within COBRA 3-CP

    SciTech Connect

    Gensler, A.; Knoll, A.; Kuehnel, K.

    2007-07-01

    In 2005 the German Reactor Safety Commission issued specific requirements on core coolability demonstration for PWR ATWS (anticipated transients without scram). Thereupon AREVA NP performed detailed analyses for all German PWRs. For a German KONVOI plant the results of an ATWS licensing analysis are presented. The plant dynamic behavior is calculated with NLOOP, while the hot channel analysis is performed with the thermal hydraulic computer code COBRA 3-CP. The application of the fuel rod model included in COBRA 3-CP is essential for this type of analysis. Since DNB (departure from nucleate boiling) occurs, the advanced post DNB model (advanced boiling curve approach) of COBRA 3-CP is used. The results are compared with those gained with the standard BEEST model. The analyzed ATWS case is the emergency power case 'loss of main heat sink with station service power supply unavailable'. Due to the decreasing coolant flow rate during the transient the core attains film boiling conditions. The results of the hot channel analysis strongly depend on the performance of the boiling curve model. The BEEST model is based on pool boiling conditions whereas typical PWR conditions - even in most transients - are characterized by forced flow for which the advanced boiling curve approach is particularly suitable. Compared with the BEEST model the advanced boiling curve approach in COBRA 3-CP yields earlier rewetting, i.e. a shorter period in film boiling. Consequently, the fuel rod cladding temperatures, that increase significantly due to film boiling, drop back earlier and the high temperature oxidation is significantly diminished. The Baker-Just-Correlation was used to calculate the value of equivalent cladding reacted (ECR), i.e. the reduction of cladding thickness due to corrosion throughout the transient. Based on the BEEST model the ECR value amounts to 0.4% whereas the advanced boiling curve only leads to an ECR value of 0.2%. Both values provide large margins to the 17% ECR limit. The maximum cladding temperature calculated with both models is almost identical. It results in approximately 830 deg. C, i.e. far below the embrittlement temperature (stipulated at 1200 deg. C). Core coolability was demonstrated with both models, with the BEEST model and with the advanced boiling curve approach. However, the advanced boiling curve approach results in more realistic values and reveals that a much higher safety margin exists. This advantage can be applied to all types of transient hot channel analyses which have to treat film boiling phases. (authors)

  12. Who Suffers during Recessions? NBER Working Paper No. 17951

    ERIC Educational Resources Information Center

    Hoynes, Hilary W.; Miller, Douglas L.; Schaller, Jessamyn

    2012-01-01

    In this paper we examine how business cycles affect labor market outcomes in the United States. We conduct a detailed analysis of how cycles affect outcomes differentially across persons of differing age, education, race, and gender, and we compare the cyclical sensitivity during the Great Recession to that in the early 1980s recession. We present

  13. Who Suffers during Recessions? NBER Working Paper No. 17951

    ERIC Educational Resources Information Center

    Hoynes, Hilary W.; Miller, Douglas L.; Schaller, Jessamyn

    2012-01-01

    In this paper we examine how business cycles affect labor market outcomes in the United States. We conduct a detailed analysis of how cycles affect outcomes differentially across persons of differing age, education, race, and gender, and we compare the cyclical sensitivity during the Great Recession to that in the early 1980s recession. We present…

  14. Recessed Lighting in the Limelight

    SciTech Connect

    Gordon, Kelly L.; McCullough, Jeffrey J.

    2003-02-01

    Recessed downlights are among the most popular installed lighting fixtures for new and remodeled homes. DOE estimates there are at least 350 million currently installed in US homes, and around 20 million are sold each year. A recent California study showed only 0.4 percent of recessed cans used compact fluorescent lamps. Annual reported sales of fluorescent residential recessed downlights nationwide make up no more than three percent of total residential recessed downlight sales. Standard recessed downlights waste energy by leaking conditioned air to unconditioned attic space, and using less efficient, high-heat incandescent bulbs. 33 states have adopted building codes that require recessed cans installed in the building shell to be airtight. To encourage lighting fixture manufacturers to bring to market high-efficiency air-tight recessed cans, DOE is sponsoring the recessed downlights project. PNNL solicited bids for energy efficient recessed downlights meeting the following specifications: They must use pin-based CFLs, have an airtight housing, be IC-rated, use electronic ballasts, and have a light output minimum of 900 initial lumens. PNNL did short- and long-term testing of the submitted lamps and negotiated lower prices for consumer purchase of qualifying models.

  15. Better P-curves: Making P-curve analysis more robust to errors, fraud, and ambitious P-hacking, a Reply to Ulrich and Miller (2015).

    PubMed

    Simonsohn, Uri; Simmons, Joseph P; Nelson, Leif D

    2015-12-01

    When studies examine true effects, they generate right-skewed p-curves, distributions of statistically significant results with more low (.01 s) than high (.04 s) p values. What else can cause a right-skewed p-curve? First, we consider the possibility that researchers report only the smallest significant p value (as conjectured by Ulrich & Miller, 2015), concluding that it is a very uncommon problem. We then consider more common problems, including (a) p-curvers selecting the wrong p values, (b) fake data, (c) honest errors, and (d) ambitiously p-hacked (beyond p < .05) results. We evaluate the impact of these common problems on the validity of p-curve analysis, and provide practical solutions that substantially increase its robustness. PMID:26595842

  16. Eprobe Mediated Real-Time PCR Monitoring and Melting Curve Analysis

    PubMed Central

    Kanamori, Hajime; Tanaka, Yuki; Kimura, Yasumasa; Nakasone, Ayako; Soma, Takahiro; Hayashizaki, Yoshihide; Usui, Kengo; Harbers, Matthias

    2013-01-01

    Real-time monitoring of PCR is one of the most important methods for DNA and RNA detection widely used in research and medical diagnostics. Here we describe a new approach for combined real-time PCR monitoring and melting curve analysis using a 3′ end-blocked Exciton-Controlled Hybridization-sensitive fluorescent Oligonucleotide (ECHO) called Eprobe. Eprobes contain two dye moieties attached to the same nucleotide and their fluorescent signal is strongly suppressed as single-stranded oligonucleotides by an excitonic interaction between the dyes. Upon hybridization to a complementary DNA strand, the dyes are separated and intercalate into the double-strand leading to strong fluorescence signals. Intercalation of dyes can further stabilize the DNA/DNA hybrid and increase the melting temperature compared to standard DNA oligonucleotides. Eprobes allow for specific real-time monitoring of amplification reactions by hybridizing to the amplicon in a sequence-dependent manner. Similarly, Eprobes allow for analysis of reaction products by melting curve analysis. The function of different Eprobes was studied using the L858R mutation in the human epidermal growth factor receptor (EGFR) gene, and multiplex detection was demonstrated for the human EGFR and KRAS genes using Eprobes with two different dyes. Combining amplification and melting curve analysis in a single-tube reaction provides powerful means for new mutation detection assays. Functioning as “sequence-specific dyes”, Eprobes hold great promises for future applications not only in PCR but also as hybridization probes in other applications. PMID:23951046

  17. Differentiating between monozygotic twins through DNA methylation-specific high-resolution melt curve analysis.

    PubMed

    Stewart, Leander; Evans, Neil; Bexon, Kimberley J; van der Meer, Dieudonne J; Williams, Graham A

    2015-05-01

    Although short tandem repeat profiling is extremely powerful in identifying individuals from crime scene stains, it is unable to differentiate between monozygotic (MZ) twins. Efforts to address this include mutation analysis through whole genome sequencing and through DNA methylation studies. Methylation of DNA is affected by environmental factors; thus, as MZ twins age, their DNA methylation patterns change. This can be characterized by bisulfite treatment followed by pyrosequencing. However, this can be time-consuming and expensive; thus, it is unlikely to be widely used by investigators. If the sequences are different, then in theory the melting temperature should be different. Thus, the aim of this study was to assess whether high-resolution melt curve analysis can be used to differentiate between MZ twins. Five sets of MZ twins provided buccal swabs that underwent extraction, quantification, bisulfite treatment, polymerase chain reaction amplification and high-resolution melting curve analysis targeting two markers, Alu-E2F3 and Alu-SP. Significant differences were observed between all MZ twins targeting Alu-E2F3 and in four of five MZ twins targeting Alu-SP (P<0.05). Thus, it has been demonstrated that bisulfite treatment followed by high-resolution melting curve analysis could be used to differentiate between MZ twins. PMID:25677265

  18. The Study of SLC26A4 Gene Causing Autosomal Recessive Hearing Loss by Linkage Analysis in a Cohort of Iranian Populations

    PubMed Central

    Reiisi, Somayeh; Sanati, Mohammad Hosein; Tabatabaiefar, Mohammad Amin; Ahmadian, Shahla; Reiisi, Salimeh; Parchami, Shahrbanoo; Porjafari, Hamid; Shahi, Heshmat; Shavarzi, Afsaneh; Hashemzade Chaleshtori, Morteza

    2014-01-01

    Sensorineural non-syndromic hearing loss is the most common disorder which affects 1 in 500 newborns. Hearing loss is an extremely heterogeneous defect with more than 100 loci identified to date. According to the studies, mutations in GJB2 are estimated to be involved in 50- 80% of autosomal recessive non-syndromic hearing loss cases, but contribution of other loci in this disorder is yet ambiguous. With regard to studies, DFNB4 locus (SLC26A4) can be classified as the second cause of hearing loss. So, this study aimed to determine the contribution of this locus in hearing loss as well as the frequency of SLC26A4 gene mutations in a population in the west of Iran. In this descriptive laboratory study, we included 30 families from the west of Iran with no mutation in GJB2 gene. Linkage analysis was performed by DFNB4 (SLC26A4) molecular markers (STR). The families with hearing loss linked to this locus were further analyzed for mutation detection. SLC26A4 gene exons were amplified and analyzed using direct DNA sequencing. In studied families, 2 families displayed linkage to DFNB4 locus. Identified mutations include mutation in exon 5 (c.416 G>T) and in splicing site of exon 7 (IVS-2 A>G or c.919-2 A>G). PMID:25317404

  19. The Study of SLC26A4 Gene Causing Autosomal Recessive Hearing Loss by Linkage Analysis in a Cohort of Iranian Populations.

    PubMed

    Reiisi, Somayeh; Sanati, Mohammad Hosein; Tabatabaiefar, Mohammad Amin; Ahmadian, Shahla; Reiisi, Salimeh; Parchami, Shahrbanoo; Porjafari, Hamid; Shahi, Heshmat; Shavarzi, Afsaneh; Hashemzade Chaleshtori, Morteza

    2014-01-01

    Sensorineural non-syndromic hearing loss is the most common disorder which affects 1 in 500 newborns. Hearing loss is an extremely heterogeneous defect with more than 100 loci identified to date. According to the studies, mutations in GJB2 are estimated to be involved in 50- 80% of autosomal recessive non-syndromic hearing loss cases, but contribution of other loci in this disorder is yet ambiguous. With regard to studies, DFNB4 locus (SLC26A4) can be classified as the second cause of hearing loss. So, this study aimed to determine the contribution of this locus in hearing loss as well as the frequency of SLC26A4 gene mutations in a population in the west of Iran. In this descriptive laboratory study, we included 30 families from the west of Iran with no mutation in GJB2 gene. Linkage analysis was performed by DFNB4 (SLC26A4) molecular markers (STR). The families with hearing loss linked to this locus were further analyzed for mutation detection. SLC26A4 gene exons were amplified and analyzed using direct DNA sequencing. In studied families, 2 families displayed linkage to DFNB4 locus. Identified mutations include mutation in exon 5 (c.416 G>T) and in splicing site of exon 7 (IVS-2 A>G or c.919-2 A>G). PMID:25317404

  20. Fort Play Children Recreate Recess

    ERIC Educational Resources Information Center

    Powell, Mark

    2007-01-01

    Recess beckons well before it actually arrives. Its allure can be heard in children's lunchtime conversations as they discuss imaginary roles, plans, alliances and teams, with an obvious appetite for play and its unbounded possibility. For some children, recess provides the most important reasons to come to school. In team sports, games of chase…

  1. Endoscopic Gastrocnemius Intramuscular Aponeurotic Recession

    PubMed Central

    Lui, Tun Hing

    2015-01-01

    Gastrocnemius aponeurotic recession is the surgical treatment for symptomatic gastrocnemius contracture. Endoscopic gastrocnemius recession procedures has been developed recently and reported to have fewer complications and better cosmetic outcomes. Classically, this is performed at the aponeurosis distal to the gastrocnemius muscle attachment. We describe an alternative endoscopic approach in which the intramuscular portion of the aponeurosis is released. PMID:26900563

  2. Light curve solution and orbital period analysis of the contact binary V842 Herculis

    NASA Astrophysics Data System (ADS)

    Selam, S. O.; Albayrak, B.; Şenavci, H. V.; Aksu, O.

    2005-10-01

    New photoelectric BV light curves were obtained for the neglected eclipsing binary V842 Her at the TÜB{İTAK National Observatory (TUG) and studied for the first time in detail to determine the orbital parameters and geometry of the system. The solutions obtained simultaneously for the new light curves and the radial velocity curves in the literature by using the Wilson-Devinney code reveal a typical W-type contact system. The light curves exhibit the so-called O'Connell effect which the level of the primary maxima being higher than that of the secondary ones in both pass-bands. The O'Connell effect in the light curves is explained in terms of a dark-spot located on the more massive component which makes the more massive larger component slightly cooler than the less massive smaller one. The O-C diagram constructed for all available times of minima of V842 Her exhibits a cyclic character superimposed on a quadratic variation. The quadratic character yields a orbital period increase with a rate of dP/dt=7.76×10-7 days yr-1 which can be attributed to the mass exchange/loss mechanism in the system. By assuming the presence of a gravitationally bound third body in the system, the analysis of the cyclic nature in the O-C diagram revealed a third body with mass of 0.4M\\sun orbiting around the eclipsing pair. The possibility of magnetic activity cycle effect as a cause for the observed cyclic variation in the O-C diagram was also discussed.

  3. A deformation analysis of flat flexible gear and its equation of original curved surfaces

    NASA Technical Reports Server (NTRS)

    Yunwen, S.

    1985-01-01

    The equation of the original curved surface of end harmonic gearing is determined by displacement analysis of flat flexible gear. The displacement analysis is also used to calculate the strength and rigidity of the gear. The latter is regarded as a circular plate with two concentrated loads, since its torsional rigidity is much larger than its bending rigidity. Small-deflection theory of thin plates is used to solve for the displacement of any point in the middle plane of the gear. New expressions are given for radial and tangential displacements of the middle plane under asymmetrical loading. A digital computer is used to obtain numerical values for the displacements.

  4. Prediction of Cooling Curves for Squeeze Cast Al/SiCp Composites Using Finite Element Analysis

    NASA Astrophysics Data System (ADS)

    Gurusamy, P.; Balasivanandha Prabu, S.; Paskaramoorthy, R.

    2015-04-01

    This paper reports the experimental and finite element analyses of the solidification behavior of Al/SiCp composites, fabricated by the squeeze casting technique. Experiments were carried out by varying the melt temperatures for cylindrical-shaped composite castings. The composite samples were produced at the following constant temperatures: melt—1023 K, 1073 K, 1123 K, and 1173 K (750 °C, 800 °C, 850 °C, and 900 °C); and die—673 K (400 °C). The pressure applied throughout the experiment is 100 MPa. The melt temperature shows significant influence on the solidification behavior of the metal matrix composite. It was observed that the solidification time was 40 seconds when the melt temperature was 1023 K (750 °C) but it increased to 51 seconds when the melt temperature was at 1173 K (900 °C). The results also showed that the cooling rate decreased on increasing the melt temperature. Cooling curves for our system, squeeze cast composites, were predicted using the finite element software ANSYS. K-type thermocouples were interfaced to the die and the microcomputer from which the experimental cooling curves were constructed. The experimental and predicted cooling curves were then compared. While both show similar trends, the finite element analysis consistently under-predicts the temperature. In addition, finite element stress analysis reveals that both radial and tangential thermal stresses increase with the melt temperature.

  5. Thermal deformation and residual stress analysis of lightweight piezocomposite curved actuator device

    NASA Astrophysics Data System (ADS)

    Yoon, Kwang J.; Chung, Jae H.; Goo, Nam Seo; Park, Hoon C.

    2001-07-01

    LIPCA (LIghtweight Piezo-composite Curved Actuator) is an actuator device which is lighter than other conventional piezoelectric ceramic type actuator. LIPCA is composed of a piezoelectric ceramic layer and fiber reinforced light composite layers, typically a PZT ceramic layer is sandwiched by a top fiber layer with low CTE (Coefficient of thermal expansion) and base layers with high CTE. LIPCA has curved shape like a typical THUNDER (Thin-layer composite unimorph ferroelectric driver and sensor), but it is lighter than THUNDER. Since the curved shape of LIPCA is from the thermal deformation during the manufacturing process of unsymmetrically laminated lay-up structure, and analysis for the thermal deformation and residual stresses induced during the manufacturing process is very important for an optimal design to increase the performance of LIPCA. To investigate the thermal deformation behavior and the induced residual stresses of LIPCA at room temperature, the curvatures of LIPCA were measured and compared with those predicted from the analysis using the classical lamination theory. A methodology is being studied to find an optimal stacking sequence and geometry of LIPCA to have larger specific actuating displacement and higher force. The residual stresses induced during the cooling process of the piezo- composite actuators have been calculated. A lay-up geometry for the PZT ceramic layer to have compression stress in the geometrical principal direction has been designed.

  6. ROC curve regression analysis: the use of ordinal regression models for diagnostic test assessment.

    PubMed Central

    Tosteson, A N; Weinstein, M C; Wittenberg, J; Begg, C B

    1994-01-01

    Diagnostic tests commonly are characterized by their true positive (sensitivity) and true negative (specificity) classification rates, which rely on a single decision threshold to classify a test result as positive. A more complete description of test accuracy is given by the receiver operating characteristic (ROC) curve, a graph of the false positive and true positive rates obtained as the decision threshold is varied. A generalized regression methodology, which uses a class of ordinal regression models to estimate smoothed ROC curves has been described. Data from a multi-institutional study comparing the accuracy of magnetic resonance (MR) imaging with computed tomography (CT) in detecting liver metastases, which are ideally suited for ROC regression analysis, are described. The general regression model is introduced and an estimate for the area under the ROC curve and its standard error using parameters of the ordinal regression model is given. An analysis of the liver data that highlights the utility of the methodology in parsimoniously adjusting comparisons for covariates is presented. PMID:7851336

  7. Analysis of Lamb wave dispersion curve sensitivity to material elastic constants in composites

    NASA Astrophysics Data System (ADS)

    Gallina, Alberto; Pieczonka, Lukasz; Ambrozinski, Lukasz; Packo, Pawel; Nazarko, Piotr; Uhl, Tadeusz; Waszczyszyn, Zenon

    2015-03-01

    The paper deals with the problem of Lamb waves dispersion curves sensitivity to the change of elastic constants in composite materials. The framework of the present work is a more general problem of material constants identification in thin plates made of composite materials. The approach is based on the analysis of guided waves propagation and the related dispersion curves to find the underlying material elastic constants. In present work a numerical study is performed to identify measurement directions and wave propagation modes that are most sensitive to the change of the particular elastic constants. This approach will allow to optimize the material constants identification procedure and experimental setup by specifying the preferred measurement directions and wave propagation modes. The approach can be used within the Structural Health Monitoring framework to monitor material degradation of plate-like structures made of composite materials.

  8. A computerized glow curve analysis (GCA) method for WinREMS thermoluminescent dosimeter data using MATLAB.

    PubMed

    Harvey, John A; Rodrigues, Miesher L; Kearfott, Kimberlee J

    2011-09-01

    A computerized glow curve analysis (GCA) program for handling of thermoluminescence data originating from WinREMS is presented. The MATLAB program fits the glow peaks using the first-order kinetics model. Tested materials are LiF:Mg,Ti, CaF(2):Dy, CaF(2):Tm, CaF(2):Mn, LiF:Mg,Cu,P, and CaSO(4):Dy, with most having an average figure of merit (FOM) of 1.3% or less, with CaSO(4):Dy 2.2% or less. Output is a list of fit parameters, peak areas, and graphs for each fit, evaluating each glow curve in 1.5 s or less. PMID:21561783

  9. A New Computational Tool for the Phenomenological Analysis of Multipassage Tumor Growth Curves

    PubMed Central

    Gliozzi, Antonio S.; Guiot, Caterina; Delsanto, Pier Paolo

    2009-01-01

    Multipassage experiments are performed by subcutaneous implantation in lab animals (usually mice) of a small number of cells from selected human lines. Tumor cells are then passaged from one mouse to another by harvesting them from a growing tumor and implanting them into other healthy animals. This procedure may be extremely useful to investigate the various mechanisms involved in the long term evolution of tumoral growth. It has been observed by several researchers that, contrary to what happens in in vitro experiments, there is a significant growth acceleration at each new passage. This result is explained by a new method of analysis, based on the Phenomenological Universalities approach. It is found that, by means of a simple rescaling of time, it is possible to collapse all the growth curves, corresponding to the successive passages, into a single curve, belonging to the Universality Class U2. Possible applications are proposed and the need of further experimental evidence is discussed. PMID:19396358

  10. Computer programs for describing the recession of ground-water discharge and for estimating mean ground-water recharge and discharge from streamflow records-update

    USGS Publications Warehouse

    Rutledge, A.T.

    1998-01-01

    The computer programs included in this report can be used to develop a mathematical expression for recession of ground-water discharge and estimate mean ground-water recharge and discharge. The programs are intended for analysis of the daily streamflow record of a basin where one can reasonably assume that all, or nearly all, ground water discharges to the stream except for that which is lost to riparian evapotranspiration, and where regulation and diversion of flow can be considered to be negligible. The program RECESS determines the master reces-sion curve of streamflow recession during times when all flow can be considered to be ground-water discharge and when the profile of the ground-water-head distribution is nearly stable. The method uses a repetitive interactive procedure for selecting several periods of continuous recession, and it allows for nonlinearity in the relation between time and the logarithm of flow. The program RORA uses the recession-curve displacement method to estimate the recharge for each peak in the streamflow record. The method is based on the change in the total potential ground-water discharge that is caused by an event. Program RORA is applied to a long period of record to obtain an estimate of the mean rate of ground-water recharge. The program PART uses streamflow partitioning to estimate a daily record of base flow under the streamflow record. The method designates base flow to be equal to streamflow on days that fit a requirement of antecedent recession, linearly interpolates base flow for other days, and is applied to a long period of record to obtain an estimate of the mean rate of ground-water discharge. The results of programs RORA and PART correlate well with each other and compare reasonably with results of the corresponding manual method.

  11. Ice shelf structure derived from dispersion curve analysis of ambient seismic noise, Ross Ice Shelf, Antarctica

    NASA Astrophysics Data System (ADS)

    Diez, A.; Bromirski, P. D.; Gerstoft, P.; Stephen, R. A.; Anthony, R. E.; Aster, R.; Cai, C.; Nyblade, A.; Wiens, D. A.

    2016-02-01

    An L-configured, three-component short period seismic array was deployed on the Ross Ice Shelf, Antarctica during November 2014. Polarization analysis of ambient noise data from these stations shows linearly polarized waves for frequency bands between 0.2-2 Hz. A spectral peak at about 1.6 Hz is interpreted as the resonance frequency of the water column, and is used to estimate the water layer thickness below the ice shelf. The frequency band from 4 to 18 Hz is dominated by Rayleigh and Love waves propagating from the north that, based on daily temporal variations, we conclude were generated by field camp activity. Frequency-slowness plots were calculated using beamforming. Resulting Love and Rayleigh wave dispersion curves were inverted for the shear wave velocity profile within the firn and ice to ˜150 m depth. The derived density profile allows estimation of the pore close-off depth and the firn-air content thickness. Separate inversions of Rayleigh and Love wave dispersion curves gives different shear-wave velocity profiles within the firn. We attribute this difference to an effective anisotropy due to fine layering. The layered structure of firn, ice, water, and the seafloor results in a characteristic dispersion curve below 7 Hz. Forward modeling the observed Rayleigh wave dispersion curves using representative firn, ice, water, sediment structures indicates that Rayleigh waves are observed when wavelengths are long enough to span the distance from the ice shelf surface to the seafloor. The forward modeling shows that analysis of seismic data from an ice shelf provides the possibility of resolving ice shelf thickness, water column thickness, and the physical properties of the ice shelf and underlying seafloor using passive-source seismic data.

  12. Ice shelf structure derived from dispersion curve analysis of ambient seismic noise, Ross Ice Shelf, Antarctica

    NASA Astrophysics Data System (ADS)

    Diez, A.; Bromirski, P. D.; Gerstoft, P.; Stephen, R. A.; Anthony, R. E.; Aster, R. C.; Cai, C.; Nyblade, A.; Wiens, D. A.

    2016-05-01

    An L-configured, three-component short period seismic array was deployed on the Ross Ice Shelf, Antarctica during November 2014. Polarization analysis of ambient noise data from these stations shows linearly polarized waves for frequency bands between 0.2 and 2 Hz. A spectral peak at about 1.6 Hz is interpreted as the resonance frequency of the water column and is used to estimate the water layer thickness below the ice shelf. The frequency band from 4 to 18 Hz is dominated by Rayleigh and Love waves propagating from the north that, based on daily temporal variations, we conclude were generated by field camp activity. Frequency-slowness plots were calculated using beamforming. Resulting Love and Rayleigh wave dispersion curves were inverted for the shear wave velocity profile within the firn and ice to ˜150 m depth. The derived density profile allows estimation of the pore close-off depth and the firn-air content thickness. Separate inversions of Rayleigh and Love wave dispersion curves give different shear wave velocity profiles within the firn. We attribute this difference to an effective anisotropy due to fine layering. The layered structure of firn, ice, water and the seafloor results in a characteristic dispersion curve below 7 Hz. Forward modelling the observed Rayleigh wave dispersion curves using representative firn, ice, water and sediment structures indicates that Rayleigh waves are observed when wavelengths are long enough to span the distance from the ice shelf surface to the seafloor. The forward modelling shows that analysis of seismic data from an ice shelf provides the possibility of resolving ice shelf thickness, water column thickness and the physical properties of the ice shelf and underlying seafloor using passive-source seismic data.

  13. 3D combinational curves for accuracy and performance analysis of positive biometrics identification

    NASA Astrophysics Data System (ADS)

    Du, Yingzi; Chang, Chein-I.

    2008-06-01

    The receiver operating characteristic (ROC) curve has been widely used as an evaluation criterion to measure the accuracy of biometrics system. Unfortunately, such an ROC curve provides no indication of the optimum threshold and cost function. In this paper, two kinds of 3D combinational curves are proposed: the 3D combinational accuracy curve and the 3D combinational performance curve. The 3D combinational accuracy curve gives a balanced view of the relationships among FAR (false alarm rate), FRR (false rejection rate), threshold t, and Cost. Six 2D curves can be derived from the 3D combinational accuracy curve: the conventional 2D ROC curve, 2D curve of (FRR, t), 2D curve of (FAR, t), 2D curve of (FRR, Cost), 2D curve of (FAR, Cost), and 2D curve of ( t, Cost). The 3D combinational performance curve can be derived from the 3D combinational accuracy curve which can give a balanced view among Security, Convenience, threshold t, and Cost. The advantages of using the proposed 3D combinational curves are demonstrated by iris recognition systems where the experimental results show that the proposed 3D combinational curves can provide more comprehensive information of the system accuracy and performance.

  14. Consequence analysis to determine damage to buildings from vapour cloud explosions using characteristic curves.

    PubMed

    Alonso, Fernando Díaz; Ferradás, Enrique González; Pérez, Juan Francisco Sánchez; Aznar, Agustín Miñana; Gimeno, José Ruiz; Miñarro, Marta Doval

    2008-11-30

    The objective of this paper is to propose a methodology to estimate the consequences to buildings from the pressure wave caused by unconfined vapour cloud explosions (VCEs). This methodology is based on the use of characteristic overpressure-impulse-distance curves, shown in a previous paper [F. Diaz Alonso, E. Gonzalez Ferradas, J.F. Sanchez Perez, A. Miñana Aznar, J. Ruiz Gimeno, J. Martinez Alonso, Characteristic overpressure-impulse-distance curves for vapour cloud, explosions using the TNO Multi-Energy model, J. Hazard. Mater. A137 (2006) 734-741]. They allow the overpressure and impulse at each distance from the explosion to be determined. Since they can be combined with damage criteria (such as those shown by the PROBIT equations), they can be used to perform consequence analysis as the damage is shown in the same diagram as the overpressure, impulse and distance. Since damages suffered by buildings usually affect people inside, it is important to take them into account when performing consequence analysis. This is done in this paper, where diagrams and equations are presented to determine minor damage to buildings (broken windows, displacement of doors and window frames, tile displacement, etc.), major structural damage (cracks in walls, collapse of some walls) and collapse (the damage is so extensive that the building is partially or totally demolished). This paper completes the consequence analysis to humans outdoors shown by F.D. Alonso et al. [F. Diaz Alonso, E. Gonzalez Ferradas, T. Jimenez Sanchez, A. Miñana Aznar, J. Ruiz Gimeno, J. Martinez Alonso, Consequence analysis to determine the damage to humans from vapour cloud explosions using characteristic curves, J. Hazard. Mater., in press]. PMID:18367326

  15. Improved Protocol for Rapid Identification of Certain Spa Types Using High Resolution Melting Curve Analysis

    PubMed Central

    Mayerhofer, Benjamin; Stöger, Anna; Pietzka, Ariane T.; Fernandez, Haizpea Lasa; Prewein, Bernhard; Sorschag, Sieglinde; Kunert, Renate; Allerberger, Franz; Ruppitsch, Werner

    2015-01-01

    Methicillin-resistant Staphylococcus aureus is one of the most significant pathogens associated with health care. For efficient surveillance, control and outbreak investigation, S. aureus typing is essential. A high resolution melting curve analysis was developed and evaluated for rapid identification of the most frequent spa types found in an Austrian hospital consortium covering 2,435 beds. Among 557 methicillin-resistant Staphylococcus aureus isolates 38 different spa types were identified by sequence analysis of the hypervariable region X of the protein A gene (spa). Identification of spa types through their characteristic high resolution melting curve profiles was considerably improved by double spiking with genomic DNA from spa type t030 and spa type t003 and allowed unambiguous and fast identification of the ten most frequent spa types t001 (58%), t003 (12%), t190 (9%), t041 (5%), t022 (2%), t032 (2%), t008 (2%), t002 (1%), t5712 (1%) and t2203 (1%), representing 93% of all isolates within this hospital consortium. The performance of the assay was evaluated by testing samples with unknown spa types from the daily routine and by testing three different high resolution melting curve analysis real-time PCR instruments. The ten most frequent spa types were identified from all samples and on all instruments with 100% specificity and 100% sensitivity. Compared to classical spa typing by sequence analysis, this gene scanning assay is faster, cheaper and can be performed in a single closed tube assay format. Therefore it is an optimal screening tool to detect the most frequent endemic spa types and to exclude non-endemic spa types within a hospital. PMID:25768007

  16. Modeling and regression analysis of semiochemical dose-response curves of insect antennal reception and behavior.

    PubMed

    Byers, John A

    2013-08-01

    Dose-response curves of the effects of semiochemicals on neurophysiology and behavior are reported in many articles in insect chemical ecology. Most curves are shown in figures representing points connected by straight lines, in which the x-axis has order of magnitude increases in dosage vs. responses on the y-axis. The lack of regression curves indicates that the nature of the dose-response relationship is not well understood. Thus, a computer model was developed to simulate a flux of various numbers of pheromone molecules (10(3) to 5 × 10(6)) passing by 10(4) receptors distributed among 10(6) positions along an insect antenna. Each receptor was depolarized by at least one strike by a molecule, and subsequent strikes had no additional effect. The simulations showed that with an increase in pheromone release rate, the antennal response would increase in a convex fashion and not in a logarithmic relation as suggested previously. Non-linear regression showed that a family of kinetic formation functions fit the simulated data nearly perfectly (R(2) >0.999). This is reasonable because olfactory receptors have proteins that bind to the pheromone molecule and are expected to exhibit enzyme kinetics. Over 90 dose-response relationships reported in the literature of electroantennographic and behavioral bioassays in the laboratory and field were analyzed by the logarithmic and kinetic formation functions. This analysis showed that in 95% of the cases, the kinetic functions explained the relationships better than the logarithmic (mean of about 20% better). The kinetic curves become sigmoid when graphed on a log scale on the x-axis. Dose-catch relationships in the field are similar to dose-EAR (effective attraction radius, in which a spherical radius indicates the trapping effect of a lure) and the circular EARc in two dimensions used in mass trapping models. The use of kinetic formation functions for dose-response curves of attractants, and kinetic decay curves for inhibitors, will allow more accurate predictions of insect catch in monitoring and control programs. PMID:23897111

  17. Spectrophotometric analysis of gamma-ray burst afterglow extinction curves with X-Shooter

    NASA Astrophysics Data System (ADS)

    Japelj, J.; Covino, S.; Gomboc, A.; Vergani, S. D.; Goldoni, P.; Selsing, J.; Cano, Z.; D'Elia, V.; Flores, H.; Fynbo, J. P. U.; Hammer, F.; Hjorth, J.; Jakobsson, P.; Kaper, L.; Kopač, D.; Krühler, T.; Melandri, A.; Piranomonte, S.; Sánchez-Ramírez, R.; Tagliaferri, G.; Tanvir, N. R.; de Ugarte Postigo, A.; Watson, D.; Wijers, R. A. M. J.

    2015-07-01

    We use gamma-ray burst (GRB) afterglow spectra observed with the VLT/X-Shooter spectrograph to measure rest-frame extinction in GRB lines-of-sight by modelling the broadband near-infrared (NIR) to X-ray afterglow spectral energy distributions (SEDs). Our sample consists of nine Swift GRBs, of which eight belong to the long-duration and one to the short-duration class. Dust is modelled using the average extinction curves of the Milky Way and the two Magellanic Clouds. We derive the rest-frame extinction of the entire sample, which fall in the range 0 ≲ AV ≲ 1.2. Moreover, the SMC extinction curve is the preferred extinction curve template for the majority of our sample, a result that is in agreement with those commonly observed in GRB lines of sights. In one analysed case (GRB 120119A), the common extinction curve templates fail to reproduce the observed extinction. To illustrate the advantage of using the high-quality, X-Shooter afterglow SEDs over the photometric SEDs, we repeat the modelling using the broadband SEDs with the NIR-to-UV photometric measurements instead of the spectra. The main result is that the spectroscopic data, thanks to a combination of excellent resolution and coverage of the blue part of the SED, are more successful in constraining extinction curves and therefore dust properties in GRB hosts with respect to photometric measurements. In all cases but one the extinction curve of one template is preferred over the others. We show that themodelled values of the extinction AV and the spectral slope, obtained through spectroscopic and photometric SED analysis, can differ significantly for individual events, though no apparent trend in the differences is observed. Finally we stress that, regardless of the resolution of the optical-to-NIR data, the SED modelling gives reliable results only when the fit is performed on a SED covering a broader spectral region (in our case extending to X-rays). Based on observations collected at the European Southern Observatory, Paranal, Chile, under programs 084.A-0260(B), 085.A-0009(B), 088.A-0051(B), 089.A-0067(B) and 091.C-0934(C).Appendix A is available in electronic form at http://www.aanda.org

  18. Numerical analysis of transient heat conduction in downward-facing curved sections during quenching

    SciTech Connect

    Gao, C.; El-Genk, M.S.

    1996-12-31

    Pool boiling from downward-facing surfaces is of interest in many applications such as cooling of electric cables, handling of containers of hazardous liquids and external cooling of nuclear reactor vessels. Here, a two-dimensional numerical analysis was performed to determine pool boiling curves from downward-facing curved stainless-steel and copper surfaces during quenching in saturated water. To ensure stability and accuracy of the numerical solution, the alternating direction implicit (ADI) method based on finite control volume representations was employed. A time dependent boundary condition was provided by the measured temperature at nine interior locations near the boiling surface. Best results were obtained using a grid of 20x20 CVs and a non-iterative approach. Calculated temperatures near the top surface of the metal sections agreed with measured values to within 0.5 K and 2.5 K for the copper and stainless-steel sections, respectively. The running time on a Pentium 90 MHz PC for the entire boiling curve was 7% of the real transient time and 4% of that of a simplified Gaussian elimination (SGE) method for the Crank-Nicolson scheme.

  19. A Modern BVRI Light Curve and Analysis of the Eclipsing Binary EO Aurigae

    NASA Astrophysics Data System (ADS)

    Wolf, G. W.; Caffey, J. F.

    1997-12-01

    iEO Aurigae was discovered to be an eclipsing binary with a 4.07 day period by S. Gaposchkin (1943) and was originally assumed from the spectroscopic analysis of Pearce (1943) to have two almost-identical, high-mass B3 III components. Popper (1978) indicated that the spectra showed the components to be less-massive O9 and B3 stars. Previous analyses of available light curves by Ramella et al. (1980) and Hartigan (1981) show marked disagreements in the values of the photometric elements. As a part of our long-term program to obtain modern light curves of interesting double-lined binary systems, we have observed EO Aurigae for the past three observing seasons on the 0.4 meter telescope at the Baker Observatory of SW Missouri State University. New light curves in the Cousins BVRI passbands have been obtained with our Photometrics CCD system, and a new model for EO Aurigae has been determined using the Wilson-Devinney program. This research has been supported by NSF grants AST-9315061 and AST-9605822 and NASA grant NGT-40029.

  20. The SuperNovae Analysis Application (SNAP): A new tool for rapid analysis of SNe light curves and model verification

    NASA Astrophysics Data System (ADS)

    Bayless, Amanda J.; SNAP Development Team

    2016-01-01

    The SuperNovae Analysis Application (SNAP) is a new tool for the analysis of SNe observations and validation of SNe models. SNAP consists of two data bases, an observational light curve data base and a theoretical light curve model data base, statistical comparison software, and a web interface available to the community. The observational light curves are primarily Swift UVOT core-collapse SNe and include all available observations from these observed SNe. The currently available theoretical models were developed at LANL. The web interface allows approved users to upload new SNe models or new SNe observations. The comparison software will validate new models against available SNe observations or rapidly give constraints on parameters for newly discovered SNe. With the advent of large computing abilities, more sophisticated SNe models are being developed. SNAP will be a tool to determine the accuracy of these new models. SNAP will also be a useful tool in the era of large surveys where thousands of SNe are discovered annually. Frequently, the parameter space of a new SNe event is unbounded. SNAP will be a resource to constrain parameters and determine if an event needs follow up without spending resources to create new light curve models from scratch.

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

    PubMed

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

    2015-07-01

    For better determination of the chemical components in the Puer black tea, Fourier transform infrared spectroscopy was used for obtaining vibrational spectra of Puer black tea at different aging time. Fourier transform infrared (FTIR) spectra indicated that the chemical components had change in Puer black tea at different aging time. The leaf of Puer black tea was a complex system, its Fourier transform infrared spectrum showed a total overlap of each absorption spectrum of various components. Each band represented an overall overlap of some characteristic absorption peaks of functional groups in the Puer black tea. In order to explore the change of characteristic absorption peaks of functional groups with aging time, the prediction positions and the number of second peaks in the range of 1900-900 cm(-1) were determined by Fourier self-deconvolution at first, and later the curve fitting analysis was performed in this overlap band. At different aging time of Puer black tea, the wave number of second peaks of amide II, tea polyphenol, pectin and polysaccharides at overlap band were assigned by curve fitting analysis. The second peak at 1520 cm(-1) was characteristic absorption band of amide II, the second peaks of tea polyphenol and pectin appeared at 1278 and 1103 cm(-1) respectively. Two second peaks at 1063 and 1037 cm(-1), corresponds mainly to glucomannan and arabinan. The relative area of these second peaks could be indicated the content of protein, tea polyphenol, pectin and polysaccharides in the Puer black tea. The results of curve fitting analysis showed that the relative area of amide II was increasing first and then decreasing, it indicated the change of protein in Puer black tea. At the same time, the content of tea polyphenol and pectin were decreased with the increase of aging time, but the glucomannan and arabinan were increased in reverse. It explained that the bitter taste was become weak and a sweet taste appeared in the tea with the increase of aging time. The present study suggested that Fourier transform infrared spectroscopy combined with curve-fitting analysis could reveal the biochemical changed of Puer black tea with the increase of aging time, and it was evidence for evaluation the quality of Puer black tea. PMID:26717740

  2. Optimized curve design for image analysis using localized geodesic distance transformations

    NASA Astrophysics Data System (ADS)

    Braithwaite, Billy; Niska, Harri; Pöllänen, Irene; Ikonen, Tiia; Haataja, Keijo; Toivanen, Pekka; Tolonen, Teemu

    2015-03-01

    We consider geodesic distance transformations for digital images. Given a M × N digital image, a distance image is produced by evaluating local pixel distances. Distance Transformation on Curved Space (DTOCS) evaluates shortest geodesics of a given pixel neighborhood by evaluating the height displacements between pixels. In this paper, we propose an optimization framework for geodesic distance transformations in a pattern recognition scheme, yielding more accurate machine learning based image analysis, exemplifying initial experiments using complex breast cancer images. Furthermore, we will outline future research work, which will complete the research work done for this paper.

  3. On the Analysis and Construction of the Butterfly Curve Using "Mathematica"[R

    ERIC Educational Resources Information Center

    Geum, Y. H.; Kim, Y. I.

    2008-01-01

    The butterfly curve was introduced by Temple H. Fay in 1989 and defined by the polar curve r = e[superscript cos theta] minus 2 cos 4 theta plus sin[superscript 5] (theta divided by 12). In this article, we develop the mathematical model of the butterfly curve and analyse its geometric properties. In addition, we draw the butterfly curve and…

  4. On the Analysis and Construction of the Butterfly Curve Using "Mathematica"[R

    ERIC Educational Resources Information Center

    Geum, Y. H.; Kim, Y. I.

    2008-01-01

    The butterfly curve was introduced by Temple H. Fay in 1989 and defined by the polar curve r = e[superscript cos theta] minus 2 cos 4 theta plus sin[superscript 5] (theta divided by 12). In this article, we develop the mathematical model of the butterfly curve and analyse its geometric properties. In addition, we draw the butterfly curve and

  5. What's Getting in the Way of Play? An Analysis of the Contextual Factors that Hinder Recess in Elementary Schools

    ERIC Educational Resources Information Center

    McNamara, Lauren

    2013-01-01

    This article describes the first two years of an ongoing, collaborative action research project focused on the troubled recess environment in 4 elementary schools in southern Ontario. The project involves an iterative, dynamic process of inquiry, planning, action, and reflection among students, teachers, university researchers, university student…

  6. Improved factor analysis of dynamic PET images to estimate arterial input function and tissue curves

    NASA Astrophysics Data System (ADS)

    Boutchko, Rostyslav; Mitra, Debasis; Pan, Hui; Jagust, William; Gullberg, Grant T.

    2015-03-01

    Factor analysis of dynamic structures (FADS) is a methodology of extracting time-activity curves (TACs) for corresponding different tissue types from noisy dynamic images. The challenges of FADS include long computation time and sensitivity to the initial guess, resulting in convergence to local minima far from the true solution. We propose a method of accelerating and stabilizing FADS application to sequences of dynamic PET images by adding preliminary cluster analysis of the time activity curves for individual voxels. We treat the temporal variation of individual voxel concentrations as a set of time-series and use a partial clustering analysis to identify the types of voxel TACs that are most functionally distinct from each other. These TACs provide a good initial guess for the temporal factors for subsequent FADS processing. Applying this approach to a set of single slices of dynamic 11C-PIB images of the brain allows identification of the arterial input function and two different tissue TACs that are likely to correspond to the specific and non-specific tracer binding-tissue types. These results enable us to perform direct classification of tissues based on their pharmacokinetic properties in dynamic PET without relying on a compartment-based kinetic model, without identification of the reference region, or without using any external methods of estimating the arterial input function, as needed in some techniques.

  7. DECLINE CURVE ANALYSIS FOR INFINITE DOUBLE-POROSITY SYSTEMS WITHOUT WELLBORE SKIN

    SciTech Connect

    Sageev, A.; Da Prat, G.; Ramey Jr., H.J.

    1985-01-22

    This paper presents a transient pressure analysis method for analyzing the rate decline of a constant pressure well producing in an infinite double-porosity reservoir, without wellbore skin. This analysis method may be used to interpret well test rate data, and to compute the rate behavior of an infinitely acting reservoir that is being produced at constant pressure. The development of the pseudo steady state log-log type curve Is presented along with a hypothetical example of its use. This type curve allows the estimation of the two controlling parameters in double-porosity systems: {lambda} and {omega}. The first parameter, {lambda}, describes the interporosity flow, and the second parameter, {omega} describes the relative fracture storativity. This paper considers the estimation of these two parameters. The estimations of permeabilities and storativities have been described in the past, hence, are not considered. In a double-porosity system, with pseudo steady state interporosity flow, the initial infinite acting rate decline, representing only the fracture system, is followed by a constant rate flow period. The length of this constant rate flow period is controlled by the parameter {omega}. The beginning of this period is controlled by the interporosity flow parameter, {lambda}. Following this constant rate period, the rate resumes an infinite homogeneous decline, representing the total system, fractures and matrix. The parameters {lambda} and {omega} may be estimated from a log-log match of rate data to the type curve. A comparison between rate responses of two transient flowing matrices and the pseudo steady state matrix Is presented. Transient interporosity flow allows the matrix to increase the well flowrate in the early and transition portions of the flow. The final decline, representing the total system, is identical to the decline with a pseudo steady state matrix.

  8. Single fluorophore melting curve analysis for detection of hypervirulent Clostridium difficile.

    PubMed

    Angione, Stephanie L; Croote, Derek; Leung, Joshua W; Mermel, Leonard A; Tripathi, Anubhav

    2016-01-01

    This study demonstrates a novel detection assay able to identify and subtype strains of Clostridium difficile. Primers carefully designed for melting curve analysis amplify DNA from three C. difficile genes, tcdB, tcdC and cdtB, during quantitative (q)PCR. The tcdB gene allows for confirmation of organism presence, whilst the tcdC and cdtB genes allow for differentiation of virulence status, as deletions in the tcdC gene and the concurrent presence of the cdtB gene, which produces binary toxin, are associated with hypervirulence. Following qPCR, subtyping is then achieved by automated, inline melting curve analysis using only a single intercalating dye and verified by microchip electrophoresis. This assay represents a novel means of distinguishing between toxigenic and hypervirulent C. difficile strains NAP1/027/BI and 078 ribotype, which are highly prevalent hypervirulent strains in humans. This methodology can help rapidly detect and identify C. difficile strains that impose a significant health and economic burden in hospitals and other healthcare settings. PMID:26516039

  9. A Scientific Analysis of Galaxy Tangential Speed of Revolution Curves III

    NASA Astrophysics Data System (ADS)

    Taff, Laurence

    2015-04-01

    I last reported on my preliminary analysis of 350 + spiral, lenticular, irregular, polar ring, ring, and dwarf elliptical galaxies' tangential speed of revolution curves [TSRCs; and not rotation (sic) curves]. I now know that the consensus opinion in the literature--for which I can find no geometrical, numerical, statistical, nor scientific testing in 2,500 + publications--that the TSRC, vB(r), in the central bulges of these galaxies, is a linear function of the radial distance from the minor axis of symmetry r--is false. For the majority (>98%) vB(r) is rarely well represented by vB(r) = ωB r (for which the unique material model is an homogeneous, oblate, spheroid). Discovered via a scientific analysis of the gravitational potential energy computed directly from the observational data, vB(r) is almost exactly given by vB2(r) = (ωB r)2(1 + η r2) with | η | < 10-2 and frequently orders of magnitude less. The corresponding mass model is the simplest generalization: a two component homoeoid. The set of possible periodic orbits, based on circular trigonometric functions, becomes a set of periodic orbits based on the Jacobian elliptic functions. Once again it is possible to prove that the mass-to-light ratio can neither be a constant nor follow the de Vaucouleurs R1/4 rule.

  10. Nonlinear Analysis and Post-Test Correlation for a Curved PRSEUS Panel

    NASA Technical Reports Server (NTRS)

    Gould, Kevin; Lovejoy, Andrew E.; Jegley, Dawn; Neal, Albert L.; Linton, Kim, A.; Bergan, Andrew C.; Bakuckas, John G., Jr.

    2013-01-01

    The Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) concept, developed by The Boeing Company, has been extensively studied as part of the National Aeronautics and Space Administration's (NASA s) Environmentally Responsible Aviation (ERA) Program. The PRSEUS concept provides a light-weight alternative to aluminum or traditional composite design concepts and is applicable to traditional-shaped fuselage barrels and wings, as well as advanced configurations such as a hybrid wing body or truss braced wings. Therefore, NASA, the Federal Aviation Administration (FAA) and The Boeing Company partnered in an effort to assess the performance and damage arrestments capabilities of a PRSEUS concept panel using a full-scale curved panel in the FAA Full-Scale Aircraft Structural Test Evaluation and Research (FASTER) facility. Testing was conducted in the FASTER facility by subjecting the panel to axial tension loads applied to the ends of the panel, internal pressure, and combined axial tension and internal pressure loadings. Additionally, reactive hoop loads were applied to the skin and frames of the panel along its edges. The panel successfully supported the required design loads in the pristine condition and with a severed stiffener. The panel also demonstrated that the PRSEUS concept could arrest the progression of damage including crack arrestment and crack turning. This paper presents the nonlinear post-test analysis and correlation with test results for the curved PRSEUS panel. It is shown that nonlinear analysis can accurately calculate the behavior of a PRSEUS panel under tension, pressure and combined loading conditions.

  11. Spectral analysis of stellar light curves by means of neural networks

    NASA Astrophysics Data System (ADS)

    Tagliaferri, R.; Ciaramella, A.; Milano, L.; Barone, F.; Longo, G.

    1999-06-01

    Periodicity analysis of unevenly collected data is a relevant issue in several scientific fields. In astrophysics, for example, we have to find the fundamental period of light or radial velocity curves which are unevenly sampled observations of stars. Classical spectral analysis methods are unsatisfactory to solve the problem. In this paper we present a neural network based estimator system which performs well the frequency extraction in unevenly sampled signals. It uses an unsupervised Hebbian nonlinear neural algorithm to extract, from the interpolated signal, the principal components which, in turn, are used by the MUSIC frequency estimator algorithm to extract the frequencies. The neural network is tolerant to noise and works well also with few points in the sequence. We benchmark the system on synthetic and real signals with the Periodogram and with the Cramer-Rao lower bound. This work was been partially supported by IIASS, by MURST 40\\% and by the Italian Space Agency.

  12. School Recess: Implications for Education and Development.

    ERIC Educational Resources Information Center

    Pellegrini, A. D.; Smith, Peter K.

    1993-01-01

    Empirical research on the role of school recess is reviewed. Effects of child-level and school-level variables on recess behavior and the impact of recess on classroom behavior and social and cognitive competence are discussed. It is concluded that recess has important educational and developmental implications. (SLD)

  13. Evidence of genetic heterogeneity in the autosomal recessive adult forms of limb-girdle muscular dystrophy following linkage analysis with 15q probes in Brazilian families.

    PubMed Central

    Passos-Bueno, M R; Richard, I; Vainzof, M; Fougerousse, F; Weissenbach, J; Broux, O; Cohen, D; Akiyama, J; Marie, S K; Carvalho, A A

    1993-01-01

    The autosomal recessive limb-girdle muscular dystrophies (LGMD) represent a heterogeneous group of diseases which may be characterised by one or more autosomal loci. A gene at 15q has recently been found to be responsible for a mild form of LGMD in a group of families from the isolated island of Réunion, now classified as LGMD2. Based on results of eight out of 11 large Brazilian LGMD families of different racial background (which were informative for the closest available probe to the LGMD2 gene), we confirmed linkage to the LGMD2 gene at 15q in two of these families and exclusion in six others. These data provide the first evidence of genetic heterogeneity for the autosomal recessive limb-girdle muscular dystrophies. PMID:8320700

  14. Determination of secondary flow morphologies by wavelet analysis in a curved artery model with physiological inflow

    NASA Astrophysics Data System (ADS)

    Bulusu, Kartik V.; Hussain, Shadman; Plesniak, Michael W.

    2014-11-01

    Secondary flow vortical patterns in arterial curvatures have the potential to affect several cardiovascular phenomena, e.g., progression of atherosclerosis by altering wall shear stresses, carotid atheromatous disease, thoracic aortic aneurysms and Marfan's syndrome. Temporal characteristics of secondary flow structures vis-à-vis physiological (pulsatile) inflow waveform were explored by continuous wavelet transform (CWT) analysis of phase-locked, two-component, two-dimensional particle image velocimeter data. Measurements were made in a 180° curved artery test section upstream of the curvature and at the 90° cross-sectional plane. Streamwise, upstream flow rate measurements were analyzed using a one-dimensional antisymmetric wavelet. Cross-stream measurements at the 90° location of the curved artery revealed interesting multi-scale, multi-strength coherent secondary flow structures. An automated process for coherent structure detection and vortical feature quantification was applied to large ensembles of PIV data. Metrics such as the number of secondary flow structures, their sizes and strengths were generated at every discrete time instance of the physiological inflow waveform. An autonomous data post-processing method incorporating two-dimensional CWT for coherent structure detection was implemented. Loss of coherence in secondary flow structures during the systolic deceleration phase is observed in accordance with previous research. The algorithmic approach presented herein further elucidated the sensitivity and dependence of morphological changes in secondary flow structures on quasiperiodicity and magnitude of temporal gradients in physiological inflow conditions.

  15. Verbal learning across the lifespan: an analysis of the components of the learning curve.

    PubMed

    Blachstein, Haya; Vakil, Eli

    2016-03-01

    Previous studies on the acquisition process of verbal material, conducted separately on child and adult populations, reveal that the lifespan is characterized by an inverted-U performance curve with similar achievements at its two poles. To clarify the acquisition mechanism across the entire lifespan, the learning curve for the Rey Auditory Verbal Learning Test was reproduced for participants aged 8-91. The study utilized typical trial summary scores and a more refined analysis of trial-by-trial single-word recalls, including omissions (missed words that were previously recalled), additions (recalled words previously missed), and touched words (a count for the first recall time only, for each word during the five learning trial). A clear age effect was shown for the number of words recalled - symmetrically increases during childhood and decreases in adulthood. Similarly, increased turnover of words omitted and added characterized both incremental and decremental age differences. Measurement patterns differed for the age segments on the two sides of the lifespan, despite the similar total number of words recalled by the two sides. Acquisition pattern in children was characterized by a higher number of touched words and higher turnover than for adult groups. In contrast, older adults achieved fewer touched words and lower turnover than the child groups. This study shows that it is possible to reach the same quantitative results via different cognitive processes. The results are interpreted in terms of specific mechanisms of maturational characteristics. PMID:26186666

  16. Dispersion curves of fluid filled elastic pipes by standard FE models and eigenpath analysis

    NASA Astrophysics Data System (ADS)

    Maess, Matthias; Wagner, Nils; Gaul, Lothar

    2006-09-01

    This paper presents the application of an alternative waveguide finite element method (WFE) using standard FE-code for the computation of dispersion curves in fluid filled elastic pipes. Only one element is needed in longitudinal direction of the pipe in the FE model, which includes structural-acoustic interaction by a full coupling interface. After rearranging the dynamic stiffness matrix of the segment model in transfer matrix form, a periodicity condition is applied leading to an eigenvalue problem. Here, eigenvectors correspond to wave modes and eigenvalues are a function of the complex wavenumber. From the eigenpairs, phase velocities and group velocities of branches are computed as well as sound power transmission. Instead of solving the eigenvalue problem for each frequency separately, an eigenpath analysis is presented in order to track dispersion curves through the frequency band of interest. The numerical results are compared to results from an analytical model of a thin walled fluid-filled shell. The method allows periodic wave guides with any cross section to be analyzed while employing standard FE discretization.

  17. Design, analysis and test of composite curved frames for helicopter fuselage structure

    NASA Technical Reports Server (NTRS)

    Rich, M. J.; Lowry, D. W.

    1983-01-01

    Curved beam effects in composite frame structures representative of a light helicopter airframe are examined, and currently available analytical methods for studying these effects are briefly reviewed. A finite element study of curved composite frames is then reported, and it is shown that the curved frame effects must be accurately accounted for to avoid premature fracture. The finite element method is shown to be accurate to within 10 percent in accounting for the curved beam effects in composite structures.

  18. Learning curves for single incision and conventional laparoscopic right hemicolectomy: a multidimensional analysis

    PubMed Central

    Park, Yoonah; Yong, Yuen Geng; Jung, Kyung Uk; Huh, Jung Wook; Cho, Yong Beom; Kim, Hee Cheol; Lee, Woo Yong; Chun, Ho-Kyung

    2015-01-01

    Purpose This study aimed to compare the learning curves and early postoperative outcomes for conventional laparoscopic (CL) and single incision laparoscopic (SIL) right hemicolectomy (RHC). Methods This retrospective study included the initial 35 cases in each group. Learning curves were evaluated by the moving average of operative time, mean operative time of every five consecutive cases, and cumulative sum (CUSUM) analysis. The learning phase was considered overcome when the moving average of operative times reached a plateau, and when the mean operative time of every five consecutive cases reached a low point and subsequently did not vary by more than 30 minutes. Results Six patients with missing data in the CL RHC group were excluded from the analyses. According to the mean operative time of every five consecutive cases, learning phase of SIL and CL RHC was completed between 26 and 30 cases, and 16 and 20 cases, respectively. Moving average analysis revealed that approximately 31 (SIL) and 25 (CL) cases were needed to complete the learning phase, respectively. CUSUM analysis demonstrated that 10 (SIL) and two (CL) cases were required to reach a steady state of complication-free performance, respectively. Postoperative complications rate was higher in SIL than in CL group, but the difference was not statistically significant (17.1% vs. 3.4%). Conclusion The learning phase of SIL RHC is longer than that of CL RHC. Early oncological outcomes of both techniques were comparable. However, SIL RHC had a statistically insignificant higher complication rate than CL RHC during the learning phase. PMID:25960990

  19. Prevalence of Helicobacter pylori in symptomatic patients and detection of clarithromycin resistance using melting curve analysis

    PubMed Central

    Kaya, Ayse Demet; Öztürk, C. Elif; Akcan, Yusuf; Behçet, Mustafa; Karakoç, A. Esra; Yücel, Mihriban; Mısırlıoglu, Müge; Tuncer, Serdar

    2007-01-01

    Abstract Background: Clarithromycin is often a component of combination therapies for Helicobacter pylori eradication; however, increases in resistance rates have decreased the success of the treatment. Objective: This study was designed to determine the prevalence of H pylori infection in symptomatic patients and to detect clarithromycin resistance rates using melting curve analysis. Methods: Patients scheduled for upper endoscopy at the Endoscopy Unit of the Department of Gastroenterology, Duzce University, Medical Faculty Hospital, Konuralp/Duzce, Turkey, were assessed for enrollment in the study. Two pairs of gastric biopsy specimens (antrum and corpus) were obtained from each study patient. Histopathologic examination, rapid urease test, culture, and polymerase chain reaction (PCR) of the specimens were used to identify H pylori infection. Clarithromycin resistance was detected using melting curve analysis. Results: Seventy-five patients (41 women, 34 men; mean [SD]age, 42.6 [14.5] years [range, 17–70 years]) were included in the study. Using histopathology and rapid urease test, H pylori was detected in 40 (53.3%) of the 75 specimens. H pylori was detected using PCR in 40 (53.3%) specimens and by culture in 10 (13.3%) specimens. The specificity and sensitivity of PCR and culture were interpreted by comparing them with the results of histopathologic examination and urease tests. The specificity and sensitivity of PCR were 68.6% and 72.5%, respectively, and the specificity and sensitivity of culture were 97.1% and 22.5%, respectively. Of the 40 isolates, 21 (52.5%) were susceptible to clarithromycin, 12 (30.0%) were resistant, and a mixed susceptibility pattern was detected in 7 (17.5%) specimens. H pylori isolates from 19 (79.2%) of the 24 patients who had formerly used clarithromycin showed clarithromycin resistance. Conclusions: The prevalence of H pylori infection was 53.3% for the symptomatic patients in this study, and 47.5% of the isolates showed clarithromycin resistance using melting curve analysis. The PCR-based system used in this study was accurate for the detection of H pylori infection as well as clarithromycin susceptibility testing directly in biopsy specimens. PMID:24683206

  20. Testing and analysis of curved frame specimens made from a Long Discontinuous Fiber (LDF) material

    NASA Technical Reports Server (NTRS)

    Jegley, Dawn C.

    1993-01-01

    A long discontinuous fiber (LDF) material may be useful for constructing composite parts with complex curvature. Graphite-thermoplastic LDF curved frame specimens were studied to investigate the behavior of curved frame structures made from this material form. Experimental results for three curved frame specimens loaded in a four-point-bending configuration and finite-element predictions of strains and displacements are presented.

  1. Multivariate curve resolution for hyperspectral image analysis :applications to microarray technology.

    SciTech Connect

    Van Benthem, Mark Hilary; Sinclair, Michael B.; Haaland, David Michael; Martinez, M. Juanita (University of New Mexico, Albuquerque, NM); Timlin, Jerilyn Ann; Werner-Washburne, Margaret C. (University of New Mexico, Albuquerque, NM); Aragon, Anthony D. (University of New Mexico, Albuquerque, NM)

    2003-01-01

    Multivariate curve resolution (MCR) using constrained alternating least squares algorithms represents a powerful analysis capability for a quantitative analysis of hyperspectral image data. We will demonstrate the application of MCR using data from a new hyperspectral fluorescence imaging microarray scanner for monitoring gene expression in cells from thousands of genes on the array. The new scanner collects the entire fluorescence spectrum from each pixel of the scanned microarray. Application of MCR with nonnegativity and equality constraints reveals several sources of undesired fluorescence that emit in the same wavelength range as the reporter fluorphores. MCR analysis of the hyperspectral images confirms that one of the sources of fluorescence is due to contaminant fluorescence under the printed DNA spots that is spot localized. Thus, traditional background subtraction methods used with data collected from the current commercial microarray scanners will lead to errors in determining the relative expression of low-expressed genes. With the new scanner and MCR analysis, we generate relative concentration maps of the background, impurity, and fluorescent labels over the entire image. Since the concentration maps of the fluorescent labels are relatively unaffected by the presence of background and impurity emissions, the accuracy and useful dynamic range of the gene expression data are both greatly improved over those obtained by commercial microarray scanners.

  2. Multivariate Curve Resolution Applied to Hyperspectral Imaging Analysis of Chocolate Samples.

    PubMed

    Zhang, Xin; de Juan, Anna; Tauler, Romà

    2015-08-01

    This paper shows the application of Raman and infrared hyperspectral imaging combined with multivariate curve resolution (MCR) to the analysis of the constituents of commercial chocolate samples. The combination of different spectral data pretreatment methods allowed decreasing the high fluorescent Raman signal contribution of whey in the investigated chocolate samples. Using equality constraints during MCR analysis, estimations of the pure spectra of the chocolate sample constituents were improved, as well as their relative contributions and their spatial distribution on the analyzed samples. In addition, unknown constituents could be also resolved. White chocolate constituents resolved from Raman hyperspectral image indicate that, at macro scale, sucrose, lactose, fat, and whey constituents were intermixed in particles. Infrared hyperspectral imaging did not suffer from fluorescence and could be applied for white and milk chocolate. As a conclusion of this study, micro-hyperspectral imaging coupled to the MCR method is confirmed to be an appropriate tool for the direct analysis of the constituents of chocolate samples, and by extension, it is proposed for the analysis of other mixture constituents in commercial food samples. PMID:26162693

  3. Texture analysis and segmentation using modulation features, generative models, and weighted curve evolution.

    PubMed

    Kokkinos, Iasonas; Evangelopoulos, Georgios; Maragos, Petros

    2009-01-01

    In this work we approach the analysis and segmentation of natural textured images by combining ideas from image analysis and probabilistic modeling. We rely on AM-FM texture models and specifically on the Dominant Component Analysis (DCA) paradigm for feature extraction. This method provides a low-dimensional, dense and smooth descriptor, capturing essential aspects of texture, namely scale, orientation, and contrast. Our contributions are at three levels of the texture analysis and segmentation problems: First, at the feature extraction stage we propose a Regularized Demodulation Algorithm that provides more robust texture features and explore the merits of modifying the channel selection criterion of DCA. Second, we propose a probabilistic interpretation of DCA and Gabor filtering in general, in terms of Local Generative Models. Extending this point of view to edge detection facilitates the estimation of posterior probabilities for the edge and texture classes. Third, we propose the Weighted Curve Evolution scheme that enhances the Region Competition/ Geodesic Active Regions methods by allowing for the locally adaptive fusion of heterogeneous cues. Our segmentation results are evaluated on the Berkeley Segmentation Benchmark, and compare favorably to current state-of-the-art methods. PMID:19029552

  4. Multivariate curve resolution: a powerful tool for the analysis of conformational transitions in nucleic acids.

    PubMed

    Jaumot, Joaquim; Escaja, Nria; Gargallo, Raimundo; Gonzlez, Carlos; Pedroso, Enrique; Tauler, Rom

    2002-09-01

    A successful application is reported of the multivariate curve resolution alternating least-squares method (MCR-ALS) for the analysis of nucleic acid melting and salt-induced transitions. Under conditions where several structures co-exist in a conformational equilibrium, MCR-ALS analysis of the UV and circular dichroism (CD) spectra at different temperatures, ionic strength and oligonucleotide concentration allows for the resolution of concentration profiles and pure spectra of the different species. The methodology is illustrated by the case of the cyclic oligonucleotide d. The melting transition of this molecule at different oligonucleotide concentrations was studied at 0, 2 and 10 mM MgCl2 by UV and CD spectroscopy. In addition, salt titration experiments were carried out at 21.0 and 54.0 degrees C. The MCR-ALS analysis indicates that three different conformations of this molecule co-exist in solution. In agreement with previous NMR studies, these conformations were assigned to a monomeric dumbbell-like structure, a dimeric four-stranded conformation and a disordered (random coil) structure. The MCR-ALS methodology allows for a detailed analysis of how this equilibrium is affected by temperature, salt and oligonucleotide concentration. PMID:12202780

  5. Magnetostatic interaction in soft magnetic bilayer ribbons unambiguously identified by first-order reversal curve analysis

    NASA Astrophysics Data System (ADS)

    Rivas, M.; Martínez-García, J. C.; Škorvánek, I.; Marcin, J.; Švec, P.; Gorria, P.

    2015-09-01

    Monolithic amorphous Fe73.5Nb3Si13.5B9Cu1/Fe74.5Nb3Si13.5B9 bilayer ribbons were obtained by double-nozzle melt-spinning and subsequently annealed to produce a composite with a tailored nano/micro-crystalline structure. The overall magnetic behavior is characterized by butterfly-shaped high field hysteresis loops and positively biased low field ones. The main questions we wish to address here are whether the global magnetic behavior of the bilayer can be separated into the individual contributions of each layer and the magneto-coupling between them can be well understood. For that purpose, we performed first-order reversal curve analysis, which enabled us to distinctly identify two phases, of ultra-soft and semi-soft magnetic natures, whose mutual predominant interaction is the magnetostatic coupling.

  6. Characterization of the magnetic interactions of multiphase magnetocaloric materials using first-order reversal curve analysis

    NASA Astrophysics Data System (ADS)

    Franco, V.; Bron, F.; Pirota, K. R.; Knobel, M.; Willard, M. A.

    2015-05-01

    In order to understand the magnetocaloric response of materials, it is important to analyze the interactions between the different phases present in them. Recent models have analyzed the influence of these interactions on the magnetocaloric response of composites, providing an estimate value of the interaction field that is consistent with experimental results. This paper analyzes to which extent magnetization first-order reversal curve (FORC) method can be used to calculate these interactions. It is shown that the different field ranges that are explored using these techniques (inside the hysteretic region for FORC; close to magnetic saturation for magnetocaloric effect) produce interaction field values that differ in order of magnitude, with FORC being sensitive to the lower values of the interaction field and magnetocaloric analysis accounting for the larger interactions.

  7. Analysis and computation of three-dimensional flow in strongly curved ducts

    NASA Technical Reports Server (NTRS)

    Kreskovsky, J. P.; Briley, W. R.; Mcdonald, H.

    1981-01-01

    Numerical solutions are presented for three-dimensional laminar and turbulent flow in curved ducts of rectangular cross section and significant curvature. The analysis is based on a primary-secondary velocity decomposition in a given coordinate system, and leads to approximate governing equations which correct an a priori inviscid solution for viscous effects, secondary flows, total pressure distortion, heat transfer, and internal flow blockage and losses. Solution of the correction equations is accomplished as an initial-value problem in space using an implicit forward-marching technique. The overall solution procedure requires significantly less computational effort than Navier-Stokes algorithms. The present solution procedure is effective even with the extreme local mesh resolution which is necessary to resolve near-wall sublayer regions in turbulent flow calculations. Computed solutions for both laminar and turbulent flow compare very favorably with available analytical and experimental results.

  8. Correlation Analysis of Optical and Radio Light Curves for a Large Sample of Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Clements, S. D.; Smith, A. G.; Aller, H. D.; Aller, M. F.

    1995-08-01

    The Rosemary Hill Observatory has accumulated internally consistent light curves extending over as much as 26 years for a large sample of active galactic nuclei. Forty-six of these optical records have been compared with similar radio records from the University of Michigan Radio Astronomy Observatory and the Algonquin Radio Observatory. For 18 objects, pairs of records were sufficiently long and unconfused to allow reliable application of the Discrete Correlation Function analysis; this group included 8 BL Lacertids, 8 quasars, and 2 Seyfert galaxies. Nine of the 18 sources showed positive radio-optical correlations, with the radio events lagging the optical by intervals ranging from 0 to 14 months. Consistent with the relativistic beaming model of the BL Lacertids, the group displaying correlations was dominated by this type of object.

  9. Vibration analysis and transient response of a functionally graded piezoelectric curved beam with general boundary conditions

    NASA Astrophysics Data System (ADS)

    Su, Zhu; Jin, Guoyong; Ye, Tiangui

    2016-06-01

    The paper presents a unified solution for free and transient vibration analyses of a functionally graded piezoelectric curved beam with general boundary conditions within the framework of Timoshenko beam theory. The formulation is derived by means of the variational principle in conjunction with a modified Fourier series which consists of standard Fourier cosine series and supplemented functions. The mechanical and electrical properties of functionally graded piezoelectric materials (FGPMs) are assumed to vary continuously in the thickness direction and are estimated by Voigt’s rule of mixture. The convergence, accuracy and reliability of the present formulation are demonstrated by comparing the present solutions with those from the literature and finite element analysis. Numerous results for FGPM beams with different boundary conditions, geometrical parameters as well as material distributions are given. Moreover, forced vibration of the FGPM beams subjected to dynamic loads and general boundary conditions are also investigated.

  10. Single-channel multiplexing without melting curve analysis in real-time PCR

    PubMed Central

    Lee, Young-Jo; Kim, Daeyoung; Lee, Kihoon; Chun, Jong-Yoon

    2014-01-01

    Multiplex real-time PCR with quantification of targets in a single fluorescence channel has been the demand in biotechnology industry. Here, we develop a novel analytical real-time PCR technique to detect multiple targets in a single fluorescence channel without melting curve analysis. In this technique, we show the intensity of the fluorescence signals of two discrete Tm targets is different at certain temperatures called detection temperatures, by which a high Tm target can be detected regardless of a low Tm target. We then identify the low Tm target by utilizing a change of the fluorescence signals between two different detection temperatures. Furthermore, it enables us to determine quantification of each target in a single channel, possibly facilitating convenient patient care for drug treatment in clinics. PMID:25501038

  11. Kepler light-curve analysis of the blazar W2R 1926+42

    NASA Astrophysics Data System (ADS)

    Mohan, P.; Gupta, Alok C.; Bachev, Rumen; Strigachev, Anton

    2016-02-01

    We study the long term Kepler light curve of the blazar W2R 1926+42 (˜1.6 yr) which indicates a variety of variability properties during different intervals of observation. The normalized excess variance, Fvar ranges from 1.8 per cent in the quiescent phase and 43.3 per cent in the outburst phase. We find no significant deviation from linearity in the Fvar-flux relation. Time series analysis is conducted using the Fourier power spectrum and the wavelet analysis methods to study the power spectral density (PSD) shape, infer characteristic time-scales and statistically significant quasi-periodic oscillations (QPOs). A bending power law with an associated time-scale of T_B = 6.2^{+6.4}_{-3.1} hours is inferred in the PSD analysis. We obtain a black hole mass of M• = (1.5-5.9) × 107 M⊙ for the first time using Fvar and the bend time-scale for this source. From a mean outburst lifetime of days, we infer a distance from the jet base r ≤ 1.75 pc indicating that the outburst originates due to a shock. A possible QPO peaked at 9.1 d and lasting 3.4 cycles is inferred from the wavelet analysis. Assuming that the QPO is a true feature, r = (152-378)GM•/c2 and supported by the other timing analysis products such as a weighted mean PSD slope of -1.5 ± 0.2 from the PSD analysis, we argue that the observed variability and the weak and short duration QPO could be due to jet based processes including orbital features in a relativistic helical jet and others such as shocks and turbulence.

  12. Evaluation of drug-polymer solubility curves through formal statistical analysis: comparison of preparation techniques.

    PubMed

    Knopp, Matthias Manne; Olesen, Niels Erik; Holm, Per; Löbmann, Korbinian; Holm, René; Langguth, Peter; Rades, Thomas

    2015-01-01

    In this study, the influence of the preparation technique (ball milling, spray drying, and film casting) of a supersaturated amorphous dispersion on the quality of solubility determinations of indomethacin in polyvinylpyrrolidone was investigated by means of statistical analysis. After annealing of the amorphous dispersions above the crystallization temperature for 2 h, the solubility curve was derived from the glass transition temperature of the demixed material using the Gordon-Taylor relationship and fitting with the Flory-Huggins model. The study showed that the predicted solubility from the ball-milled mixtures was not consistent with those from spray drying and film casting, indicating fundamental differences between the preparation techniques. Through formal statistical analysis, the best combination of fit to the Flory-Huggins model and reproducibility of the measurements was analyzed. Ball milling provided the best reproducibility of the three preparation techniques; however, an analysis of residuals revealed a systematic error. In contrast, film casting demonstrated a good fit to the model but poor reproducibility of the measurements. Therefore, this study recommends that techniques such as spray drying or potentially film casting (if experimental reproducibility can be improved) should be used to prepare the amorphous dispersions when performing solubility measurements of this kind. PMID:25363890

  13. Analysis of Surface Plasmon Resonance Curves with a Novel Sigmoid-Asymmetric Fitting Algorithm

    PubMed Central

    Jang, Daeho; Chae, Geunhyoung; Shin, Sehyun

    2015-01-01

    The present study introduces a novel curve-fitting algorithm for surface plasmon resonance (SPR) curves using a self-constructed, wedge-shaped beam type angular interrogation SPR spectroscopy technique. Previous fitting approaches such as asymmetric and polynomial equations are still unsatisfactory for analyzing full SPR curves and their use is limited to determining the resonance angle. In the present study, we developed a sigmoid-asymmetric equation that provides excellent curve-fitting for the whole SPR curve over a range of incident angles, including regions of the critical angle and resonance angle. Regardless of the bulk fluid type (i.e., water and air), the present sigmoid-asymmetric fitting exhibited nearly perfect matching with a full SPR curve, whereas the asymmetric and polynomial curve fitting methods did not. Because the present curve-fitting sigmoid-asymmetric equation can determine the critical angle as well as the resonance angle, the undesired effect caused by the bulk fluid refractive index was excluded by subtracting the critical angle from the resonance angle in real time. In conclusion, the proposed sigmoid-asymmetric curve-fitting algorithm for SPR curves is widely applicable to various SPR measurements, while excluding the effect of bulk fluids on the sensing layer. PMID:26437414

  14. Analysis of Surface Plasmon Resonance Curves with a Novel Sigmoid-Asymmetric Fitting Algorithm.

    PubMed

    Jang, Daeho; Chae, Geunhyoung; Shin, Sehyun

    2015-01-01

    The present study introduces a novel curve-fitting algorithm for surface plasmon resonance (SPR) curves using a self-constructed, wedge-shaped beam type angular interrogation SPR spectroscopy technique. Previous fitting approaches such as asymmetric and polynomial equations are still unsatisfactory for analyzing full SPR curves and their use is limited to determining the resonance angle. In the present study, we developed a sigmoid-asymmetric equation that provides excellent curve-fitting for the whole SPR curve over a range of incident angles, including regions of the critical angle and resonance angle. Regardless of the bulk fluid type (i.e., water and air), the present sigmoid-asymmetric fitting exhibited nearly perfect matching with a full SPR curve, whereas the asymmetric and polynomial curve fitting methods did not. Because the present curve-fitting sigmoid-asymmetric equation can determine the critical angle as well as the resonance angle, the undesired effect caused by the bulk fluid refractive index was excluded by subtracting the critical angle from the resonance angle in real time. In conclusion, the proposed sigmoid-asymmetric curve-fitting algorithm for SPR curves is widely applicable to various SPR measurements, while excluding the effect of bulk fluids on the sensing layer. PMID:26437414

  15. [Application of calibration curve method and partial least squares regression analysis to quantitative analysis of nephrite samples using XRF].

    PubMed

    Liu, Song; Su, Bo-min; Li, Qing-hui; Gan, Fu-xi

    2015-01-01

    The authors tried to find a method for quantitative analysis using pXRF without solid bulk stone/jade reference samples. 24 nephrite samples were selected, 17 samples were calibration samples and the other 7 are test samples. All the nephrite samples were analyzed by Proton induced X-ray emission spectroscopy (PIXE) quantitatively. Based on the PIXE results of calibration samples, calibration curves were created for the interested components/elements and used to analyze the test samples quantitatively; then, the qualitative spectrum of all nephrite samples were obtained by pXRF. According to the PIXE results and qualitative spectrum of calibration samples, partial least square method (PLS) was used for quantitative analysis of test samples. Finally, the results of test samples obtained by calibration method, PLS method and PIXE were compared to each other. The accuracy of calibration curve method and PLS method was estimated. The result indicates that the PLS method is the alternate method for quantitative analysis of stone/jade samples. PMID:25993858

  16. Differentiation of Campylobacter jejuni and Campylobacter coli Using Multiplex-PCR and High Resolution Melt Curve Analysis

    PubMed Central

    Banowary, Banya; Dang, Van Tuan; Sarker, Subir; Connolly, Joanne H.; Chenu, Jeremy; Groves, Peter; Ayton, Michelle; Raidal, Shane; Devi, Aruna; Vanniasinkam, Thiru; Ghorashi, Seyed A.

    2015-01-01

    Campylobacter spp. are important causes of bacterial gastroenteritis in humans in developed countries. Among Campylobacter spp. Campylobacter jejuni (C. jejuni) and C. coli are the most common causes of human infection. In this study, a multiplex PCR (mPCR) and high resolution melt (HRM) curve analysis were optimized for simultaneous detection and differentiation of C. jejuni and C. coli isolates. A segment of the hippuricase gene (hipO) of C. jejuni and putative aspartokinase (asp) gene of C. coli were amplified from 26 Campylobacter isolates and amplicons were subjected to HRM curve analysis. The mPCR-HRM was able to differentiate between C. jejuni and C. coli species. All DNA amplicons generated by mPCR were sequenced. Analysis of the nucleotide sequences from each isolate revealed that the HRM curves were correlated with the nucleotide sequences of the amplicons. Minor variation in melting point temperatures of C. coli or C. jejuni isolates was also observed and enabled some intraspecies differentiation between C. coli and/or C. jejuni isolates. The potential of PCR-HRM curve analysis for the detection and speciation of Campylobacter in additional human clinical specimens and chicken swab samples was also confirmed. The sensitivity and specificity of the test were found to be 100% and 92%, respectively. The results indicated that mPCR followed by HRM curve analysis provides a rapid (8 hours) technique for differentiation between C. jejuni and C. coli isolates. PMID:26394042

  17. Patient-centered evaluation of microsurgical management of gingival recession using coronally advanced flap with platelet-rich fibrin or amnion membrane: A comparative analysis

    PubMed Central

    Agarwal, Sumit Kumar; Jhingran, Rajesh; Bains, Vivek Kumar; Srivastava, Ruchi; Madan, Rohit; Rizvi, Iram

    2016-01-01

    Objective: To evaluate the efficacy of coronally advanced flap (CAF) procedure under microsurgical approach for the management of Miller's Class I and II gingival recession defects with the use of either platelet-rich fibrin (PRF) or amnion membrane (AM) in comparison to CAF alone. Materials and Methods: A total of 45 sites with Miller's Class I or II gingival recession defect were randomly distributed for: Experimental Group I (CAF with PRF) sites (n = 15) which were treated with the microsurgical approach using CAF along with PRF; experimental Group II (CAF with AM) sites (n = 15) were treated with the microsurgical approach using CAF along with AM; control Group III (CAF alone) sites (n = 15) were treated with the microsurgical approach using CAF alone. Vertical gingival recession (VGR), horizontal gingival recession (HGR), gingival thickness (GT) (using transgingival probing [TGP] and ultrasonography [USG]) and patients’ response and acceptance were documented at baseline, 3 months and 6 months after surgical interventions. Results: CAF alone and in combination with PRF or AM, were effective techniques for root coverage with average VGR values of 1.47 ± 0.92 mm (56%), 0.67 ± 1.23 mm (36%) and 0.60 ± 1.06 mm (33%) in Group I (CAF with PRF), Group II (CAF with AM), and Group III (CAF alone), respectively. Complete coverage (100%) was obtained in 33.3% sites of Group I (CAF with PRF), 26.6% sites of Group II (CAF with AM) and 13.3% in Group III (CAF alone). Patients’ response and acceptance for surgical treatment modality in terms of patient esthetic score and decrease in hypersensitivity score was highest for Group I (CAF with PRF), whereas patient comfort score was highest for Group II (CAF with AM). At 6 months follow-up, significant increase in GT measurements (using TGP and USG) in Group I (CAF with PRF), whereas, nonsignificant increase for Group II (CAF with AM) and no change or decrease for Group III (CAF alone) as compared to baseline was observed. Conclusion: The present study observed enhancement in root coverage when PRF or AM are used in conjunction with CAF as compared to CAF alone. These results are based on 6-month follow-up. Therefore, the long-term evaluation may be necessary to appreciate the clinical effect of autologous PRF and AM. PMID:27011751

  18. Autosomal recessive primary microcephalies (MCPH).

    PubMed

    Kaindl, Angela M

    2014-07-01

    Autosomal recessive primary microcephaly (MCPH) is a genetically heterogeneous disease characterized by a pronounced reduction in volume of otherwise architectonical normal brains and intellectual deficit. Here, we summarize the genetic causes of MCPH types 1-12 known to date. PMID:24780602

  19. Firms Still Training Despite Recession

    ERIC Educational Resources Information Center

    Felstead, Alan; Green, Francis; Jewson, Nick

    2011-01-01

    It is commonly assumed that company training is one of the first casualties in times of recession. Falling recruitment, pressures to cut costs and a focus on short-term survival force businesses to put training on the backburner. Expecting the worst, the UK Commission for Employment and Skills (UKCES), the Confederation of British Industry (CBI)…

  20. Algebra, Home Mortgages, and Recessions

    ERIC Educational Resources Information Center

    Mariner, Jean A. Miller; Miller, Richard A.

    2009-01-01

    The current financial crisis and recession in the United States present an opportunity to discuss relevant applications of some topics in typical first-and second-year algebra and precalculus courses. Real-world applications of percent change, exponential functions, and sums of finite geometric sequences can help students understand the problems

  1. Algebra, Home Mortgages, and Recessions

    ERIC Educational Resources Information Center

    Mariner, Jean A. Miller; Miller, Richard A.

    2009-01-01

    The current financial crisis and recession in the United States present an opportunity to discuss relevant applications of some topics in typical first-and second-year algebra and precalculus courses. Real-world applications of percent change, exponential functions, and sums of finite geometric sequences can help students understand the problems…

  2. THE XMM-NEWTON/EPIC X-RAY LIGHT CURVE ANALYSIS OF WR 6

    SciTech Connect

    Ignace, R.; Gayley, K. G.; Hamann, W.-R.; Oskinova, L. M.; Huenemoerder, D. P.; Pollock, A. M. T.; McFall, M.

    2013-09-20

    We obtained four pointings of over 100 ks each of the well-studied Wolf-Rayet star WR 6 with the XMM-Newton satellite. With a first paper emphasizing the results of spectral analysis, this follow-up highlights the X-ray variability clearly detected in all four pointings. However, phased light curves fail to confirm obvious cyclic behavior on the well-established 3.766 day period widely found at longer wavelengths. The data are of such quality that we were able to conduct a search for event clustering in the arrival times of X-ray photons. However, we fail to detect any such clustering. One possibility is that X-rays are generated in a stationary shock structure. In this context we favor a corotating interaction region (CIR) and present a phenomenological model for X-rays from a CIR structure. We show that a CIR has the potential to account simultaneously for the X-ray variability and constraints provided by the spectral analysis. Ultimately, the viability of the CIR model will require both intermittent long-term X-ray monitoring of WR 6 and better physical models of CIR X-ray production at large radii in stellar winds.

  3. Flow Curve Analysis of 17-4 PH Stainless Steel under Hot Compression Test

    NASA Astrophysics Data System (ADS)

    Mirzadeh, Hamed; Najafizadeh, Abbas; Moazeny, Mohammad

    2009-12-01

    The hot compression behavior of a 17-4 PH stainless steel (AISI 630) has been investigated at temperatures of 950 °C to 1150 °C and strain rates of 10-3 to 10 s-1. Glass powder in the Rastegaev reservoirs of the specimen was used as a lubricant material. A step-by-step procedure for data analysis in the hot compression test was given. The work hardening rate analysis was performed to reveal if dynamic recrystallization (DRX) occurred. Many samples exhibited typical DRX stress-strain curves with a single peak stress followed by a gradual fall toward the steady-state stress. At low Zener-Hollomon ( Z) parameter, this material showed a new DRX flow behavior, which was called multiple transient steady state (MTSS). At high Z, as a result of adiabatic deformation heating, a drop in flow stress was observed. The general constitutive equations were used to determine the hot working constants of this material. Moreover, after a critical discussion, the deformation activation energy of 17-4 PH stainless steel was determined as 337 kJ/mol.

  4. A uniform analysis of HD 209458b Spitzer/IRAC light curves with Gaussian process models

    NASA Astrophysics Data System (ADS)

    Evans, Thomas M.; Aigrain, Suzanne; Gibson, Neale; Barstow, Joanna K.; Amundsen, David S.; Tremblin, Pascal; Mourier, Pierre

    2015-07-01

    We present an analysis of Spitzer/Infrared Array Camera primary transit and secondary eclipse light curves measured for HD 209458b, using Gaussian process models to marginalize over the intrapixel sensitivity variations in the 3.6 and 4.5 μm channels and the ramp effect in the 5.8 and 8.0 μm channels. The main advantage of this approach is that we can account for a broad range of degeneracies between the planet signal and systematics without actually having to specify a deterministic functional form for the latter. Our results do not confirm a previous claim of water absorption in transmission. Instead, our results are more consistent with a featureless transmission spectrum, possibly due to a cloud deck obscuring molecular absorption bands. For the emission data, our values are not consistent with the thermal inversion in the dayside atmosphere that was originally inferred from these data. Instead, we agree with another re-analysis of these same data, which concluded a non-inverted atmosphere provides a better fit. We find that a solar-abundance clear-atmosphere model without a thermal inversion underpredicts the measured emission in the 4.5 μm channel, which may suggest the atmosphere is depleted in carbon monoxide. An acceptable fit to the emission data can be achieved by assuming that the planet radiates as an isothermal blackbody with a temperature of 1484 ± 18 K.

  5. Impact Analysis of Embedded Delamination Location in Hybrid Curved Laminated Composite Stiffened Panel

    NASA Astrophysics Data System (ADS)

    Naini, Jeevan Kumar; P, Ramesh Babu

    2016-02-01

    Modern, aero structures are predominantly of curved construction characterized by a skin and stiffeners. The latest generation of large passenger aircraft also uses mostly composite material in their primary structure and there is trend towards the utilization of bonding of subcomponents. The presence of delamination is a major problem in composite laminated panels and so, it is of great concern to both the academic and aeronautical industrial worlds Indeed delamination can strongly affect the material strength and, sometimes, can cause their breaking up in service. A Pre-damaged configuration is loaded to study the delamination location and mode for delamination initiation and propagation. A parametric study is conducted to investigate the effect of the location of the delamination propagation when delamination is embedded inbetween plies of the skin-stiffener interface, with the cases i) delamination located at front and inbetween plies of the skin-stiffener interface ii) delamination located in middle and inbetween plies of the skin-stiffener interface iii) delamination located at the end and inbetween plies of the skin- stiffener interface. Further the influence of the location of the delamination on load carrying capacity of the panel is investigated. The effect of location of debonds on crack growth and collapse behavior is analyzed using analysis tool. An analysis tool is applied that includes an approach for predicting interlaminar damage initiation and interlaminar damage growth as well as in-plane damage mechanisms to predict the design of defect free panel.

  6. Numerical analysis of interaction between non-gray radiation and forced convection flow over a recess using the full-spectrum k-distribution method

    NASA Astrophysics Data System (ADS)

    Atashafrooz, M.; Gandjalikhan Nassab, S. A.; Lari, K.

    2016-02-01

    In the present work, the interaction between non-gray radiation and forced convection in a laminar radiating gas flow over a recess including two backward and forward facing steps in a duct is investigated numerically. Distributions of absorption coefficients across the spectrum (50 cm-1 < η < 20,000 cm-1) are obtained from the HITRAN2008 database. The full-spectrum k-distribution method is used to account for non-gray radiation properties, while the gray radiation calculations are carried out using the Planck mean absorption coefficient. To find the divergence of radiative heat flux distribution, the radiative transfer equation is solved by the discrete ordinates method. The effects of radiation-conduction parameter, wall emissivity, scattering coefficient and recess length on heat transfer behaviors of the convection-radiation system are investigated for both gray and non-gray mediums. In addition, the results of gray medium are compared with non-gray results in order to judge if the differences between these two approaches are significant enough to justify the usage of non-gray models. Results show that for air mixture with 10 % CO2 and 20 % H2O, use of gray model for the radiative properties may cause significant errors and should be avoided.

  7. Modeling and regression analysis of semiochemical dose-response curves of insect antennal reception and behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dose-response curves with semiochemicals are reported in many articles in insect chemical ecology regarding neurophysiology and behavioral bioassays. Most such curves are shown in figures where the x-axis has order of magnitude increases in dosages versus responses on the y-axis represented by point...

  8. Rapid differentiation of Old World Leishmania species by LightCycler polymerase chain reaction and melting curve analysis.

    PubMed

    Nicolas, Luc; Milon, Geneviève; Prina, Eric

    2002-11-01

    A LightCycler real-time polymerase chain reaction (PCR) assay has been developed to detect and differentiate four of the main Leishmania species of the Old World. The assay is based on fluorescence melting curve analysis of PCR products generated from the minicircles of kinetoplast DNA. According to the melting temperature, which is a function of GC/AT ratio, length and nucleotide sequences of the amplified product, Leishmania major was differentiated from L. donovani and from L. tropica and L. infantum. Melting curves analysis offers a rapid alternative for identification of species in diagnostic or epidemiological studies of leishmaniasis or asymptomatic parasitism. PMID:12223289

  9. First Ground-Based Photometry and Light Curve Analysis of the Recently Discovered Contact Binary Hx Uma

    NASA Astrophysics Data System (ADS)

    Selam, S.; Albayrak, B.; Yilmaz, M.; Şenavci, H. V.; Özavci, I.; Çetintaş, C.

    2005-04-01

    Photoelectric UBV light curves of the recently discovered eclipsing binary HX UMa were obtained and studied to determine the preliminary physical parameters of the system for the first time. The observations were taken at the TÜBİTAK1 Turkish National Observatory (TUG) on three nights in April 2003. A simultaneous analysis of the light and radial velocity curves yields a typical A-type contact binary with a high degree of overcontact. The influence of the close visual companion to the total light of the system was taken into account during the analysis.

  10. Qualitative and quantitative analysis of complex temperature-programmed desorption data by multivariate curve resolution

    NASA Astrophysics Data System (ADS)

    Rodríguez-Reyes, Juan Carlos F.; Teplyakov, Andrew V.; Brown, Steven D.

    2010-10-01

    The substantial amount of information carried in temperature-programmed desorption (TPD) experiments is often difficult to mine due to the occurrence of competing reaction pathways that produce compounds with similar mass spectrometric features. Multivariate curve resolution (MCR) is introduced as a tool capable of overcoming this problem by mathematically detecting spectral variations and correlations between several m/z traces, which is later translated into the extraction of the cracking pattern and the desorption profile for each desorbate. Different from the elegant (though complex) methods currently available to analyze TPD data, MCR analysis is applicable even when no information regarding the specific surface reaction/desorption process or the nature of the desorbing species is available. However, when available, any information can be used as constraints that guide the outcome, increasing the accuracy of the resolution. This approach is especially valuable when the compounds desorbing are different from what would be expected based on a chemical intuition, when the cracking pattern of the model test compound is difficult or impossible to obtain (because it could be unstable or very rare), and when knowing major components desorbing from the surface could in more traditional methods actually bias the quantification of minor components. The enhanced level of understanding of thermal processes achieved through MCR analysis is demonstrated by analyzing three phenomena: i) the cryogenic desorption of vinyltrimethylsilane from silicon, an introductory system where the known multilayer and monolayer components are resolved; ii) acrolein hydrogenation on a bimetallic Pt-Ni-Pt catalyst, where a rapid identification of hydrogenated products as well as other desorbing species is achieved, and iii) the thermal reaction of Ti[N(CH 3) 2] 4 on Si(100), where the products of surface decomposition are identified and an estimation of the surface composition after the thermal reaction is afforded. Since this work constitutes, to the best of our knowledge, the first effort to introduce multivariate analysis to TPD data, the procedures, algorithms and strategies employed are described in full detail.

  11. The role of Soil Water Retention Curve in slope stability analysis in unsaturated and heterogeneous soils.

    NASA Astrophysics Data System (ADS)

    Antinoro, Chiara; Arnone, Elisa; Noto, Leonardo V.

    2015-04-01

    The mechanisms of rainwater infiltration causing slope instability had been analyzed and reviewed in many scientific works. Rainwater infiltration into unsaturated soil increases the degree of saturation, hence affecting the shear strength properties and thus the probability of slope failure. It has been widely proved that the shear strength properties change with the soil water suction in unsaturated soils; therefore, the accuracy to predict the relationship between soil water content and soil water suction, parameterized by the soil-water characteristic curve, has significant effects on the slope stability analysis. The aim of this study is to investigate how the characterization of SWRC of differently structured unsaturated soils affects the slope stability on a simple infinite slope. In particular, the unimodal and bimodal distributions of the soil pore size were compared. Samples of 40 soils, highly different in terms of structure and texture, were collected and used to calibrate two bimodal SWRCs, i.e. Ross and Smettem (1993) and Dexter et al., (2008). The traditional unimodal van Genuchten (1980) model was also applied for comparison. Slope stability analysis was conducted in terms of Factor of Safety (FS) by applying the infinite slope model for unsaturated soils. In the used formulation, the contribution of the suction effect is tuned by a parameter 'chi' in a rate proportional to the saturation conditions. Different parameterizations of this term were also compared and analyzed. Results indicated that all three SWRC models showed good overall performance in fitting the sperimental SWRCs. Both the RS and DE models described adequately the water retention data for soils with a bimodal behavior confirmed from the analysis of pore size distribution, but the best performance was obtained by DE model confirmed. In terms of FS, the tree models showed very similar results as soil moisture approached to the saturated condition; however, within the residual zone, the DE model denoted an anomalous behavior depending on the used formulation for the 'chi' parameter, with decreasing FS as soil moisture decreases.

  12. BEER Analysis of Kepler and CoRoT Light Curves. II. Evidence for Superrotation in the Phase Curves of Three Kepler Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Faigler, S.; Mazeh, T.

    2015-02-01

    We analyzed the Kepler light curves of four transiting hot Jupiter systems—KOI-13, HAT-P-7, TrES-2, and Kepler-76, which show BEaming, Ellipsoidal, and Reflection (BEER) phase modulations. The mass of the four planets can be estimated from either the beaming or the ellipsoidal amplitude, given the mass and radius of their parent stars. For KOI-13, HAT-P-7, and Kepler-76 we find that the beaming-based planetary mass estimate is larger than the mass estimated from the ellipsoidal amplitude, consistent with previous studies. This apparent discrepancy may be explained by equatorial superrotation of the planet atmosphere, which induces an angle shift of the planet reflection/emission phase modulation, as was suggested for Kepler-76 in the first paper of this series. We propose a modified BEER model that supports superrotation, assuming either a Lambertian or geometric reflection/emission phase function, and provides a photometry-consistent estimate of the planetary mass. Our analysis shows that for Kepler-76 and HAT-P-7, the Lambertian superrotation BEER model is highly preferable over an unshifted null model, while for KOI-13 it is preferable only at a 1.4σ level. For TrES-2 we do not find such preference. For all four systems the Lambertian superrotation model mass estimates are in excellent agreement with the planetary masses derived from, or constrained by, radial velocity measurements. This makes the Lambertian superrotation BEER model a viable tool for estimating the masses of hot Jupiters from photometry alone. We conclude that hot Jupiter superrotation may be a common phenomenon that can be detected in the visual light curves of Kepler.

  13. BEER ANALYSIS OF KEPLER AND CoRoT LIGHT CURVES. II. EVIDENCE FOR SUPERROTATION IN THE PHASE CURVES OF THREE KEPLER HOT JUPITERS

    SciTech Connect

    Faigler, S.; Mazeh, T.

    2015-02-10

    We analyzed the Kepler light curves of four transiting hot Jupiter systems—KOI-13, HAT-P-7, TrES-2, and Kepler-76, which show BEaming, Ellipsoidal, and Reflection (BEER) phase modulations. The mass of the four planets can be estimated from either the beaming or the ellipsoidal amplitude, given the mass and radius of their parent stars. For KOI-13, HAT-P-7, and Kepler-76 we find that the beaming-based planetary mass estimate is larger than the mass estimated from the ellipsoidal amplitude, consistent with previous studies. This apparent discrepancy may be explained by equatorial superrotation of the planet atmosphere, which induces an angle shift of the planet reflection/emission phase modulation, as was suggested for Kepler-76 in the first paper of this series. We propose a modified BEER model that supports superrotation, assuming either a Lambertian or geometric reflection/emission phase function, and provides a photometry-consistent estimate of the planetary mass. Our analysis shows that for Kepler-76 and HAT-P-7, the Lambertian superrotation BEER model is highly preferable over an unshifted null model, while for KOI-13 it is preferable only at a 1.4σ level. For TrES-2 we do not find such preference. For all four systems the Lambertian superrotation model mass estimates are in excellent agreement with the planetary masses derived from, or constrained by, radial velocity measurements. This makes the Lambertian superrotation BEER model a viable tool for estimating the masses of hot Jupiters from photometry alone. We conclude that hot Jupiter superrotation may be a common phenomenon that can be detected in the visual light curves of Kepler.

  14. Multicolor Melting Curve Analysis-Based Multilocus Melt Typing of Vibrio parahaemolyticus.

    PubMed

    Liu, Ran; Liu, Zanzan; Xu, Ye; Liao, Yiqun; Hu, Qinghua; Huang, Jianwei; Shi, Xiaolu; Li, Yinghui; Niu, Jianjun; Li, Qingge

    2015-01-01

    Vibrio parahaemolyticus is the leading cause of seafood-borne gastroenteritis outbreaks. To track the source of these diseases in a timely manner, a high throughput typing method is critical. We hereby describe a novel genotyping method for V. parahaemolyticus, termed multilocus melt typing (MLMT), based on multilocus sequence typing (MLST). MLMT utilizes melting curve analysis to interrogate the allelic types of a set of informative single nucleotide polymorphisms (SNPs) derived from the housekeeping genes used in MLST. For each SNP, one allelic type generates distinct Tm values, which are converted into a binary code. Multiple SNPs thus generate a series of binary codes, forming a melt type (MT) corresponding with a sequence type (ST) of MLST. Using a set of 12 SNPs, the MLMT scheme could resolve 218 V.parahaemolyticus isolates into 50 MTs corresponding with 56 STs. The discriminatory power of MLMT and MLST was similar with Simpson's index of diversity of 0.638 and 0.646, respectively. The global (adjusted Rand index = 0.982) and directional congruence (adjusted Wallace coefficient, MT→ST = 0.965; ST→MT = 1.000) between the two typing approaches was high. The entire procedure of MLMT could be finished within 3 h with negligible hands on time in a real-time PCR machine. We conclude that MLMT provides a reliable and efficient approach for V. parahaemolyticus genotyping and might also find use in other pathogens. PMID:26368129

  15. Reliability analysis of laser ultrasonics for train axle diagnostics based on model assisted POD curves

    NASA Astrophysics Data System (ADS)

    Malik, M. S.; Cavuto, A.; Martarelli, M.; Pandarese, G.; Revel, G. M.

    2014-05-01

    High speed train axles are integrated for a lifetime and it is time and resource consuming to conduct in service inspection with high accuracy. Laser ultrasonics is a proposed solution as a subset of non-contact measuring methods effective also for hard to reach areas and even recently proved to be effective using Laser Doppler Vibrometer (LDV) or air-coupled probes in reception. A reliability analysis of laser ultrasonics for this specific application is here performed. The research is mainly based on numerical study of the effect of high energy laser pulses on the surface of a steel axle and of the behavior of the ultrasonic waves in detecting possible defects. Probability of Detection (POD) concept is used as an estimated reliability of the inspection method. In particular Model Assisted Probability of Detection (MAPOD), a modified form of POD where models are used to infer results for making a decisive statistical approach of POD curve, is here adopted. This paper implements this approach by taking the inputs from limited experiments conducted on a high speed train axle using laser ultrasonics (source pulsed Nd:Yag, reception by high-frequency LDV) to calibrate a multiphysics FE model and by using the calibrated model to generate data samples statistically representative of damaged train axles. The simulated flaws are in accordance with the real defects present on the axle. A set of flaws of different depth has been modeled in order to assess the laser ultrasonics POD for this specific application.

  16. Multicolor Melting Curve Analysis-Based Multilocus Melt Typing of Vibrio parahaemolyticus

    PubMed Central

    Xu, Ye; Liao, Yiqun; Hu, Qinghua; Huang, Jianwei; Shi, Xiaolu; Li, Yinghui; Niu, Jianjun; Li, Qingge

    2015-01-01

    Vibrio parahaemolyticus is the leading cause of seafood-borne gastroenteritis outbreaks. To track the source of these diseases in a timely manner, a high throughput typing method is critical. We hereby describe a novel genotyping method for V. parahaemolyticus, termed multilocus melt typing (MLMT), based on multilocus sequence typing (MLST). MLMT utilizes melting curve analysis to interrogate the allelic types of a set of informative single nucleotide polymorphisms (SNPs) derived from the housekeeping genes used in MLST. For each SNP, one allelic type generates distinct Tm values, which are converted into a binary code. Multiple SNPs thus generate a series of binary codes, forming a melt type (MT) corresponding with a sequence type (ST) of MLST. Using a set of 12 SNPs, the MLMT scheme could resolve 218 V.parahaemolyticus isolates into 50 MTs corresponding with 56 STs. The discriminatory power of MLMT and MLST was similar with Simpson’s index of diversity of 0.638 and 0.646, respectively. The global (adjusted Rand index = 0.982) and directional congruence (adjusted Wallace coefficient, MT→ST = 0.965; ST→MT = 1.000) between the two typing approaches was high. The entire procedure of MLMT could be finished within 3 h with negligible hands on time in a real-time PCR machine. We conclude that MLMT provides a reliable and efficient approach for V. parahaemolyticus genotyping and might also find use in other pathogens. PMID:26368129

  17. A study of the photo-degradation kinetics of nifedipine by multivariate curve resolution analysis.

    PubMed

    Shamsipur, Mojtaba; Hemmateenejad, Bahram; Akhond, Morteza; Javidnia, Katayoun; Miri, Ramin

    2003-04-01

    A multivariate curve resolution method based on the combination of Kubista approach and iterative target transformation method of Gemperline has been proposed. This method is a soft model and need no information about the spectrum of the product and mechanism of the reaction. The method was used to study the degradation kinetics of nifedipin, 1,4-dihydro-2,6-dimethyl-4-(2-nitrophenyl)-3,5-pyridine dicarboxilic acid dimethyl ester, upon exposure to the light of a 40 W tungsten lamp. The spectra of the nifedipine, collected at different lighting times, were subjected to the factor analysis and two chemical components were detected in the reaction system. Pure spectra of the components involved and their concentration profiles were obtained. The results revealed that the photodecomposition kinetics of nifedipine is zero-order at the beginning of the reaction. However, when the reaction preceded more than 50%, the kinetics of reaction changed to a first-order manner. The rate constants for the zero-order and first order regions were estimated as regions (4.96+/-0.13) x 10(-9) M(-1) s(-1) and (6.22+/-0.10) x 10(-5) s(-1), respectively. PMID:12684114

  18. M DWARFS IN SLOAN DIGITAL SKY SURVEY STRIPE 82: PHOTOMETRIC LIGHT CURVES AND FLARE RATE ANALYSIS

    SciTech Connect

    Kowalski, Adam F.; Hawley, Suzanne L.; Hilton, Eric J.; Becker, Andrew C.; Sesar, Branimir; West, Andrew A.; Bochanski, John J.

    2009-08-15

    We present a flare rate analysis of 50,130 M dwarf light curves in Sloan Digital Sky Survey Stripe 82. We identified 271 flares using a customized variability index to search {approx}2.5 million photometric observations for flux increases in the u and g bands. Every image of a flaring observation was examined by eye and with a point-spread function-matching and image subtraction tool to guard against false positives. Flaring is found to be strongly correlated with the appearance of H{alpha} in emission in the quiet spectrum. Of the 99 flare stars that have spectra, we classify eight as relatively inactive. The flaring fraction is found to increase strongly in stars with redder colors during quiescence, which can be attributed to the increasing flare visibility and increasing active fraction for redder stars. The flaring fraction is strongly correlated with |Z| distance such that most stars that flare are within 300 pc of the Galactic plane. We derive flare u-band luminosities and find that the most luminous flares occur on the earlier-type m dwarfs. Our best estimate of the lower limit on the flaring rate (averaged over Stripe 82) for flares with {delta}u {>=} 0.7 mag on stars with u < 22 is 1.3 flares hr{sup -1} deg{sup -2} but can vary significantly with the line of sight.

  19. High-Resolution Melting Curve Analysis for Identification of Pasteurellaceae Species in Experimental Animal Facilities

    PubMed Central

    Miller, Manuel; Zorn, Julia; Brielmeier, Markus

    2015-01-01

    Pasteurellaceae are among the most prevalent bacterial pathogens isolated from mice housed in experimental animal facilities. Reliable detection and differentiation of Pasteurellaceae are essential for high-quality health monitoring. In this study, we combined a real-time PCR assay amplifying a variable region in the 16S rRNA sequence with high-resolution melting curve analysis (HRM) to identify and differentiate among the commonly isolated species Pasteurella pneumotropica biotypes “Jawetz” and “Heyl”, Actinobacillus muris, and Haemophilus influenzaemurium. We used a set of six reference strains for assay development, with the melting profiles of these strains clearly distinguishable due to DNA sequence variations in the amplicon. For evaluation, we used real-time PCR/HRM to test 25 unknown Pasteurellaceae isolates obtained from an external diagnostic laboratory and found the results to be consistent with those of partial 16S rRNA sequencing. The real-time PCR/HRM method provides a sensitive, rapid, and closed-tube approach for Pasteurellaceae species identification for health monitoring of laboratory mice. PMID:26556281

  20. Analysis of Curved Sandwich Panels Subjected to Combined Temperature Gradient and Mechanical Loads

    NASA Technical Reports Server (NTRS)

    Noor, Ahmed K.; Starnes, James H., Jr.; Peters, Jeanne M.

    1998-01-01

    The results of a detailed study of the nonlinear response of curved sandwich panels with composite face sheets and subjected to a temperature gradient through-the-thickness combined with mechanical loadings are presented. The analysis is based on a first-order shear-deformation Sanders-Budiansky type theory with the effects of large displacements, moderate rotations, transverse shear deformation and laminated anisotropic material behavior included. A mixed formulation is used with the fundamental unknowns consisting of the generalized displacements and the stress resultants of the panel. The nonlinear displacements, strain energy, principal strains, transverse shear stresses, transverse shear strain energy density, and their hierarchical sensitivity coefficients are evaluated. The hierarchical sensitivity coefficients measure the sensitivity of the nonlinear response to variations in the panel parameters, the effective properties of the face sheet layers and the core, and the micromechanical parameters. Numerical results are presented for cylindrical panels subjected to combined pressure loading, edge shortening or extension, edge shear and a temperature gradient through the thickness. The results show the effects of variations in the loading and the panel aspect ratio, on the nonlinear response and its sensitivity to changes in the various panel, effective layer and micromechanical parameters.

  1. Multiplex Fluorescence Melting Curve Analysis for Mutation Detection with Dual-Labeled, Self-Quenched Probes

    PubMed Central

    Huang, Qiuying; Liu, Zanzan; Liao, Yiqun; Chen, Xiaoyun; Zhang, Yi; Li, Qingge

    2011-01-01

    Probe-based fluorescence melting curve analysis (FMCA) is a powerful tool for mutation detection based on melting temperature generated by thermal denaturation of the probe-target hybrid. Nevertheless, the color multiplexing, probe design, and cross-platform compatibility remain to be limited by using existing probe chemistries. We hereby explored two dual-labeled, self-quenched probes, TaqMan and shared-stem molecular beacons, in their ability to conduct FMCA. Both probes could be directly used for FMCA and readily integrated with closed-tube amplicon hybridization under asymmetric PCR conditions. Improved flexibility of FMCA by using these probes was illustrated in three representative applications of FMCA: mutation scanning, mutation identification and mutation genotyping, all of which achieved improved color-multiplexing with easy probe design and versatile probe combination and all were validated with a large number of real clinical samples. The universal cross-platform compatibility of these probes-based FMCA was also demonstrated by a 4-color mutation genotyping assay performed on five different real-time PCR instruments. The dual-labeled, self-quenched probes offered unprecedented combined advantage of enhanced multiplexing, improved flexibility in probe design, and expanded cross-platform compatibility, which would substantially improve FMCA in mutation detection of various applications. PMID:21552536

  2. Sintering Behavior of Nanocrystalline Silicon Carbide Using a Plasma Pressure Compaction System: Master Sintering Curve Analysis

    NASA Astrophysics Data System (ADS)

    Bothara, Manish G.; Atre, Sundar V.; Park, Seong-Jin; German, Randall M.; Sudarshan, T. S.; Radhakrishnan, R.

    2010-12-01

    Nanostructured ceramics offer significant improvements in properties over corresponding materials with larger grain sizes on the order of tens to hundreds of micrometers. Silicon carbide (SiC) samples with grain sizes on the order of 100 nm can result in improved strength, chemical resistance, thermal stability, and tailored electrical resistivity. In this study, nanocrystalline SiC was processed in a plasma pressure compaction (P2C) system at a temperature of 1973 K (1700 °C) that was much lower than the temperatures reported for other sintering techniques. Microstructure of the resulting samples was studied and the hardness and the fracture toughness were measured. The grain sizes were on the order of 700 nm, the hardness between 22 and 24 GPa, and the toughness between 5 and 6.5 MPa·m1/2. The master sintering curve (MSC) analysis was used to model the densification behavior of SiC powder sintered by the P2C method. The apparent activation energies for three different pressures of 10, 30, and 50 MPa were obtained to be 1666, 1034, and 1162 kJ/mol, respectively. Although densification occurs via diffusion, the activation energies were higher than those associated with self-diffusion in SiC (between 570 and 920 kJ/mol). A validation study of the MSC was also conducted and the variation in observed density from the density predicted by the MSC was found to range from 1 to 10 pct.

  3. Cognitive Vulnerabilities and Depression in Young Adults: An ROC Curves Analysis

    PubMed Central

    Sergi, Maria Rita; Continisio, Massimo; Tamburello, Antonino; Innamorati, Marco; Saggino, Aristide

    2013-01-01

    Objectives and Methods. The aim of the present study was to evaluate, by means of receiver operating characteristic (ROC) curves, whether cognitive vulnerabilities (CV), as measured by three well-known instruments (the Beck Hopelessness Scale, BHS; the Life Orientation Test-Revised, LOT-R; and the Attitudes Toward Self-Revised, ATS-R), independently discriminate between subjects with different severities of depression. Participants were 467 young adults (336 females and 131 males), recruited from the general population. The subjects were also administered the Beck Depression Inventory-II (BDI-II). Results. Four first-order (BHS Optimism/Low Standard; BHS Pessimism; Generalized Self-Criticism; and LOT Optimism) and two higher-order factors (Pessimism/Negative Attitudes Toward Self, Optimism) were extracted using Principal Axis Factoring analysis. Although all first-order and second-order factors were able to discriminate individuals with different depression severities, the Pessimism factor had the best performance in discriminating individuals with moderate to severe depression from those with lower depression severity. Conclusion. In the screening of young adults at risk of depression, clinicians have to pay particular attention to the expression of pessimism about the future. PMID:24058734

  4. Effect of intrinsic motivation on affective responses during and after exercise: latent curve model analysis.

    PubMed

    Shin, Myoungjin; Kim, Inwoo; Kwon, Sungho

    2014-12-01

    Understanding the relationship between affect and exercise is helpful in predicting human behavior with respect to exercise participation. The goals of the present study were to investigate individual differences in affective response during and after exercise and to identify the role of intrinsic motivation in affective changes. 30 active male college students (M age = 21.4 yr.) who regularly participated in sports activities volunteered to answer a questionnaire measuring intrinsic motivation toward running activities and performed a 20-min. straight running protocol at heavy intensity (about 70% of VO2max). Participants' affective responses were measured every 5 min. from the beginning of the run to 10 min. after completing the run. Latent curve model analysis indicated that individuals experienced different changes in affective state during exercise, moderated by intrinsic motivation. Higher intrinsic motivation was associated with more positive affect during exercise. There were no significant individual differences in the positive tendency of the participants' affective responses after exercise over time. Intrinsic motivation seems to facilitate positive feelings during exercise and encourages participation in exercise. PMID:25456247

  5. [Restriction endonuclease digest - melting curve analysis: a new SNP genotyping and its application in traditional Chinese medicine authentication].

    PubMed

    Jiang, Chao; Huang, Lu-Qi; Yuan, Yuan; Chen, Min; Hou, Jing-Yi; Wu, Zhi-Gang; Lin, Shu-Fang

    2014-04-01

    Single nucleotide polymorphisms (SNP) is an important molecular marker in traditional Chinese medicine research, and it is widely used in TCM authentication. The present study created a new genotyping method by combining restriction endonuclease digesting with melting curve analysis, which is a stable, rapid and easy doing SNP genotyping method. The new method analyzed SNP genotyping of two chloroplast SNP which was located in or out of the endonuclease recognition site, the results showed that when attaching a 14 bp GC-clamp (cggcgggagggcgg) to 5' end of the primer and selecting suited endonuclease to digest the amplification products, the melting curve of Lonicera japonica and Atractylodes macrocephala were all of double peaks and the adulterants Shan-yin-hua and A. lancea were of single peaks. The results indicated that the method had good stability and reproducibility for identifying authentic medicines from its adulterants. It is a potential SNP genotyping method and named restriction endonuclease digest - melting curve analysis. PMID:24974477

  6. Analysis of the variations in the light curve of U Pegasi and starspot activity

    NASA Astrophysics Data System (ADS)

    Zhai, Di-Sheng; Zhang, Xiao-Yu

    1989-03-01

    Nine two-color light curves observed between 1950 and 1983 of the W UMa type contact binary U Peg were analyzed. The distortions in the light curves during 1958-1970 can be successfully simulated with starspot activity. Using an improved W-D program containing differential correction of spot parameters, the spot parameters, longitude, latitude, temperature and radius, and their time variations are obtained. The photometric solutions at the various epochs also show that there may be other factors causing light curve distortion, including variation in the temperature difference between the two components, instability of the common shell and some other physical factors unaccounted for by present physical models.

  7. A Cognitive Approach to Elementary School Recess

    ERIC Educational Resources Information Center

    Jones, Rose B.

    2005-01-01

    This article talks about the Cognitive Recess Curriculum as a cognitive approach to elementary school recess. The concept of a cognitive recess curriculum is based on three research studies conducted by the author. The largest study involved over 1,564 educators (superintendents, principals, teachers K 12). It sought to determine the subjects'…

  8. Differences in Physical Activity during School Recess

    ERIC Educational Resources Information Center

    Ridgers, Nicola D.; Saint-Maurice, Pedro F.; Welk, Gregory J.; Siahpush, Mohammad; Huberty, Jennifer

    2011-01-01

    Background: School recess provides a daily opportunity for physical activity engagement. The purpose of this study was to examine physical activity levels during recess by gender, ethnicity, and grade, and establish the contribution of recess to daily school physical activity levels. Methods: Two hundred and ten children (45% boys) from grades 3…

  9. Spectral variations and a classical curve-of-growth analysis of HDE 226868 (Cyg X-1).

    NASA Astrophysics Data System (ADS)

    Canalizo, G.; Koenigsberger, G.; Peña, D.; Ruiz, E.

    1995-04-01

    The authors present an analysis of high resolution (R ˜ 17000) echelle spectra in the wavelength range 3200 to 6800 Å obtained at the Observatorio Astronómico Nacional at San Pedro Mártir, of HDE 226868, the optical component of the Cyg X-1 binary system. Empirical radial velocity vs. excitation (RV vs. E) relations are obtained from the spectra at 7 orbital phases and the slope (A) of these relations is found to vary, having two extrema: -0.30 km s-1eV-1 near phase 0.5 (collapsed object "in front") and -0.22 km s-1eV-1 near phase 0.0. At other phases the value is A = -0.13 km s-1eV-1. This variability in the slope of the RV vs. E relation is in very good agreement with the theoretically predicted anisotropic mass-loss rates resulting from the modified gravitational potential of the system (Friend and Castor, 1982) for the case in which the primary star fills its Roche lobe. Variations at the 25% level in the shapes and strengths of Hβ and He I photospheric absorption lines are detected. The variability of the absorption line profiles appears to correlate with the Hα and the He II 4686 Å emission line variations, suggesting that the absorption lines are contaminated by variable emission components. From a classical curve-of-growth analysis HDE 226868 is found to have Texc = 32100±1600° K, and to be overabundant in He and underabundant in C with respect to the B0 Ia supergiant ɛ Ori.

  10. Re-Analysis of the Solar Phase Curves of the Icy Galilean Satellites

    NASA Technical Reports Server (NTRS)

    Domingue, Deborah; Verbiscer, Anne

    1997-01-01

    Re-analysis of the solar phase curves of the icy Galilean satellites demonstrates that the quantitative results are dependent on the single particle scattering function incorporated into the photometric model; however, the qualitative properties are independent. The results presented here show that the general physical characteristics predicted by a Hapke model (B. Hapke, 1986, Icarus 67, 264-280) incorporating a two parameter double Henyey-Greenstein scattering function are similar to the predictions given by the same model incorporating a three parameter double Henyey-Greenstein scattering function as long as the data set being modeled has adequate coverage in phase angle. Conflicting results occur when the large phase angle coverage is inadequate. Analysis of the role of isotropic versus anisotropic multiple scattering shows that for surfaces as bright as Europa the two models predict very similar results over phase angles covered by the data. Differences arise only at those phase angles for which there are no data. The single particle scattering behavior between the leading and trailing hemispheres of Europa and Ganymede is commensurate with magnetospheric alterations of their surfaces. Ion bombardment will produce more forward scattering single scattering functions due to annealing of potential scattering centers within regolith particles (N. J. Sack et al., 1992, Icarus 100, 534-540). Both leading and trailing hemispheres of Europa are consistent with a high porosity model and commensurate with a frost surface. There are no strong differences in predicted porosity between the two hemispheres of Callisto, both are consistent with model porosities midway between that deduced for Europa and the Moon. Surface roughness model estimates predict that surface roughness increases with satellite distance from Jupiter, with lunar surface roughness values falling midway between those measured for Ganymede and Callisto. There is no obvious variation in predicted surface roughness with hemisphere for any of the Galilean satellites.

  11. BEER analysis of Kepler and CoRoT light curves. III. Spectroscopic confirmation of seventy new beaming binaries discovered in CoRoT light curves

    NASA Astrophysics Data System (ADS)

    Tal-Or, L.; Faigler, S.; Mazeh, T.

    2015-08-01

    Context. The BEER algorithm searches stellar light curves for the BEaming, Ellipsoidal, and Reflection photometric modulations that are caused by a short-period companion. These three effects are typically of very low amplitude and can mainly be detected in light curves from space-based photometers. Unlike eclipsing binaries, these effects are not limited to edge-on inclinations. Aims: Applying the algorithm to wide-field photometric surveys such as CoRoT and Kepler offers an opportunity to better understand the statistical properties of short-period binaries. It also widens the window for detecting intrinsically rare systems, such as short-period brown-dwarf and massive-planetary companions to main-sequence stars. Methods: Applying the search to the first five long-run center CoRoT fields, we identified 481 non-eclipsing candidates with periodic flux amplitudes of 0.5-87 mmag. Optimizing the Anglo-Australian-Telescope pointing coordinates and the AAOmega fiber-allocations with dedicated softwares, we acquired six spectra for 231 candidates and seven spectra for another 50 candidates in a seven-night campaign. Analysis of the red-arm AAOmega spectra, which covered the range of 8342-8842 Å, yielded a radial-velocity precision of ~1 km s-1. Spectra containing lines of more than one star were analyzed with the two-dimensional correlation algorithm TODCOR. Results: The measured radial velocities confirmed the binarity of seventy of the BEER candidates - 45 single-line binaries, 18 double-line binaries, and 7 diluted binaries. We show that red giants introduce a major source of false candidates and demonstrate a way to improve BEER's performance in extracting higher fidelity samples from future searches of CoRoT light curves. The periods of the confirmed binaries span a range of 0.3-10 days and show a rise in the number of binaries per ΔlogP toward longer periods. The estimated mass ratios of the double-line binaries and the mass ratios assigned to the single-line binaries, assuming an isotropic inclination distribution, span a range of 0.03-1. On the low-mass end, we have detected two brown-dwarf candidates on a ~1 day period orbit. Conclusions: This is the first time non-eclipsing beaming binaries are detected in CoRoT data, and we estimate that ~300 such binaries can be detected in the CoRoT long-run light curves. Full Tables 2, 4, and 5 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/580/A21

  12. Mortality due to mental and behavioral disorders associated with the Great Recession (2008-10) in Italy: a time trend analysis.

    PubMed

    De Vogli, Roberto; Vieno, Alessio; Lenzi, Michela

    2014-06-01

    We estimated the proportion of deaths due to mental and behavioral disorders attributable to the Great Recession (2008-10) in Italy. Data on standardized death rates due to mental and behavioral disorders per 100,000 from 2000 to 2010 were provided by the Italian Health for All database. There were an additional 0.303 per 100,000 deaths per year (95% CI: 0.192, 0.478; P = 0.001) because of the crisis. Each annual decrease of €1000 in gross domestic product per capita was associated with an increase of 0.126 per 100,000 (95% CI: 0.046, 0.205; P = 0.004) deaths; every annual 1% increase in unemployment corresponded to an increase of 0.074 per 100,000 (95% CI: 0.032, 0.117; P = 0.002) deaths. PMID:24248804

  13. Integrated analysis on static/dynamic aeroelasticity of curved panels based on a modified local piston theory

    NASA Astrophysics Data System (ADS)

    Yang, Zhichun; Zhou, Jian; Gu, Yingsong

    2014-10-01

    A flow field modified local piston theory, which is applied to the integrated analysis on static/dynamic aeroelastic behaviors of curved panels, is proposed in this paper. The local flow field parameters used in the modification are obtained by CFD technique which has the advantage to simulate the steady flow field accurately. This flow field modified local piston theory for aerodynamic loading is applied to the analysis of static aeroelastic deformation and flutter stabilities of curved panels in hypersonic flow. In addition, comparisons are made between results obtained by using the present method and curvature modified method. It shows that when the curvature of the curved panel is relatively small, the static aeroelastic deformations and flutter stability boundaries obtained by these two methods have little difference, while for curved panels with larger curvatures, the static aeroelastic deformation obtained by the present method is larger and the flutter stability boundary is smaller compared with those obtained by the curvature modified method, and the discrepancy increases with the increasing of curvature of panels. Therefore, the existing curvature modified method is non-conservative compared to the proposed flow field modified method based on the consideration of hypersonic flight vehicle safety, and the proposed flow field modified local piston theory for curved panels enlarges the application range of piston theory.

  14. Statistical model to perform error analysis of curve fits of wind tunnel test data using the techniques of analysis of variance and regression analysis

    NASA Technical Reports Server (NTRS)

    Alston, D. W.

    1981-01-01

    The considered research had the objective to design a statistical model that could perform an error analysis of curve fits of wind tunnel test data using analysis of variance and regression analysis techniques. Four related subproblems were defined, and by solving each of these a solution to the general research problem was obtained. The capabilities of the evolved true statistical model are considered. The least squares fit is used to determine the nature of the force, moment, and pressure data. The order of the curve fit is increased in order to delete the quadratic effect in the residuals. The analysis of variance is used to determine the magnitude and effect of the error factor associated with the experimental data.

  15. Development of synthetic velocity - depth damage curves using a Weighted Monte Carlo method and Logistic Regression analysis

    NASA Astrophysics Data System (ADS)

    Vozinaki, Anthi Eirini K.; Karatzas, George P.; Sibetheros, Ioannis A.; Varouchakis, Emmanouil A.

    2014-05-01

    Damage curves are the most significant component of the flood loss estimation models. Their development is quite complex. Two types of damage curves exist, historical and synthetic curves. Historical curves are developed from historical loss data from actual flood events. However, due to the scarcity of historical data, synthetic damage curves can be alternatively developed. Synthetic curves rely on the analysis of expected damage under certain hypothetical flooding conditions. A synthetic approach was developed and presented in this work for the development of damage curves, which are subsequently used as the basic input to a flood loss estimation model. A questionnaire-based survey took place among practicing and research agronomists, in order to generate rural loss data based on the responders' loss estimates, for several flood condition scenarios. In addition, a similar questionnaire-based survey took place among building experts, i.e. civil engineers and architects, in order to generate loss data for the urban sector. By answering the questionnaire, the experts were in essence expressing their opinion on how damage to various crop types or building types is related to a range of values of flood inundation parameters, such as floodwater depth and velocity. However, the loss data compiled from the completed questionnaires were not sufficient for the construction of workable damage curves; to overcome this problem, a Weighted Monte Carlo method was implemented, in order to generate extra synthetic datasets with statistical properties identical to those of the questionnaire-based data. The data generated by the Weighted Monte Carlo method were processed via Logistic Regression techniques in order to develop accurate logistic damage curves for the rural and the urban sectors. A Python-based code was developed, which combines the Weighted Monte Carlo method and the Logistic Regression analysis into a single code (WMCLR Python code). Each WMCLR code execution provided a flow velocity-depth damage curve for a specific land use. More specifically, each WMCLR code execution for the agricultural sector generated a damage curve for a specific crop and for every month of the year, thus relating the damage to any crop with floodwater depth, flow velocity and the growth phase of the crop at the time of flooding. Respectively, each WMCLR code execution for the urban sector developed a damage curve for a specific building type, relating structural damage with floodwater depth and velocity. Furthermore, two techno-economic models were developed in Python programming language, in order to estimate monetary values of flood damages to the rural and the urban sector, respectively. A new Monte Carlo simulation was performed, consisting of multiple executions of the techno-economic code, which generated multiple damage cost estimates. Each execution used the proper WMCLR simulated damage curve. The uncertainty analysis of the damage estimates established the accuracy and reliability of the proposed methodology for the synthetic damage curves' development.

  16. International planetary patrol observations of Saturn's rings. II - Four color phase curves and their analysis

    NASA Technical Reports Server (NTRS)

    Esposito, L. W.; Lumme, K.; Benton, W. D.; Martin, L. J.; Ferguson, H. M.; Thompson, D. T.; Jones, S. E.

    1979-01-01

    New phase curves for Saturn's rings at an intermediate tilt angle B of about 17 deg are presented. Quantitative results for each of the A and B rings are reported in terms of the opposition effect, phase coefficient, and best logarithmic fit to the phase curve. There was no significant difference between the shape of the phase curves for the two rings in each of the four colors, and a four-parameter multiple scattering model of the rings was consistent with the observations. In this model, the difference in the phase curves for different colors can be explained by a variation in the single scattering albedo with wavelength. The observations allow the particles to have the same composition in the A and B rings, so that their different photometric behavior is explained by differences in optical depth and volume density in the two rings.

  17. Ultraviolet Surface Properties of the Icy Galilean Satellites from Phase Curve Analysis

    NASA Technical Reports Server (NTRS)

    Hendrix, A. R.; Dominique, D. L.

    2002-01-01

    In this study, we use ultraviolet observations from the International Ultraviolet Explorer (IUE) and the Galileo Ultraviolet Spectrometer (UVS) to compose the ultraviolet solar phase curves of the icy Galilean satellites. Broadband rotation phase curves from 0.26 to 0.32 microns are constructed in order to examine the rotational behavior of the icy Galilean satellites in the ultraviolet. After normalizing the rotational variations, modeling of the solar phase variations are compared to comparable studies in the visible.

  18. Surgical Responses of Medial Rectus Muscle Recession in Thyroid Eye Disease-Related Esotropia

    PubMed Central

    Lyu, In Jeong; Lee, Ju-Yeun; Kong, Mingui; Park, Kyung-Ah; Oh, Sei Yeul

    2016-01-01

    We evaluate the surgical outcomes and surgical responses of medial rectus muscle (MR) recession patients with thyroid eye disease (TED)-related esotropia (ET). The surgical dose-response curves 1 week postoperatively and at the final visit were analyzed. Univariable and multivariable linear regression analyses were applied to investigate factors influencing surgical dose-response. A total of 43 patients with TED-related ET that underwent MR recession were included. The final success rate was 86.0% and the rate of undercorrection was 14.0%. The surgical dose-response curves of TED-related ET showed a gentle slope compared with those of standard surgical tables. In the univariable model, simultaneous vertical rectus muscle recession was the only significant factor influencing surgical dose-response of MR recession in TED-related ET (β = -0.397, P = 0.044). In a model adjusted for age, sex, type of surgery, and preoperative horizontal angle of deviation, simultaneous vertical rectus muscle recession showed marginal significance (β = -0.389, P = 0.064). The surgical dose-response curve of TED-related ET was unique. Simultaneous vertical rectus muscle recession was associated with increased surgical dose-response in TED-related ET. PMID:26796354

  19. Enhancing the Psychological Well-Being of Elderly Individuals through Tai Chi Exercise: A Latent Growth Curve Analysis.

    ERIC Educational Resources Information Center

    Li, Fuzhong; Duncan, Terry E.; Duncan, Susan C.; McAuley, Edward; Chaumeton, Nigel R.; Harmer, Peter

    2001-01-01

    Examined whether a Tai Chi exercise program enhanced the psychological well-being of 98 elderly individuals. Analyzed repeated measures data about participants using latent growth curve analysis. Results indicate the beneficial effects of participation in the Tai Chi program. Discusses implications related to the exercise-psychological health…

  20. Self-Esteem Trajectories among Ethnic Minority Adolescents: A Growth Curve Analysis of the Patterns and Predictors of Change

    ERIC Educational Resources Information Center

    Greene, Melissa L.; Way, Niobe

    2005-01-01

    The current study presents a growth curve analysis of self-esteem among Black, Latino, and Asian American high school students. A series of hierarchical linear models were used to examine patterns and predictors of change in self-esteem over time. Results revealed an average increase in self-esteem with age. Although boys and girls experienced…

  1. Multilevel Models for the Analysis of Angle-Specific Torque Curves with Application to Master Athletes

    PubMed Central

    Carvalho, Humberto M

    2015-01-01

    The aim of this paper was to outline a multilevel modeling approach to fit individual angle-specific torque curves describing concentric knee extension and flexion isokinetic muscular actions in Master athletes. The potential of the analytical approach to examine between individual differences across the angle-specific torque curves was illustrated including between-individuals variation due to gender differences at a higher level. Torques in concentric muscular actions of knee extension and knee extension at 60º·s−1 were considered within a range of motion between 5º and 85º (only torques “truly” isokinetic). Multilevel time series models with autoregressive covariance structures with standard multilevel models were superior fits compared with standard multilevel models for repeated measures to fit angle-specific torque curves. Third and fourth order polynomial models were the best fits to describe angle-specific torque curves of isokinetic knee flexion and extension concentric actions, respectively. The fixed exponents allow interpretations for initial acceleration, the angle at peak torque and the decrement of torque after peak torque. Also, the multilevel models were flexible to illustrate the influence of gender differences on the shape of torque throughout the range of motion and in the shape of the curves. The presented multilevel regression models may afford a general framework to examine angle-specific moment curves by isokinetic dynamometry, and add to the understanding mechanisms of strength development, particularly the force-length relationship, both related to performance and injury prevention. PMID:26839603

  2. Multilevel Models for the Analysis of Angle-Specific Torque Curves with Application to Master Athletes.

    PubMed

    Carvalho, Humberto M

    2015-12-22

    The aim of this paper was to outline a multilevel modeling approach to fit individual angle-specific torque curves describing concentric knee extension and flexion isokinetic muscular actions in Master athletes. The potential of the analytical approach to examine between individual differences across the angle-specific torque curves was illustrated including between-individuals variation due to gender differences at a higher level. Torques in concentric muscular actions of knee extension and knee extension at 60º·s(-1) were considered within a range of motion between 5º and 85º (only torques "truly" isokinetic). Multilevel time series models with autoregressive covariance structures with standard multilevel models were superior fits compared with standard multilevel models for repeated measures to fit angle-specific torque curves. Third and fourth order polynomial models were the best fits to describe angle-specific torque curves of isokinetic knee flexion and extension concentric actions, respectively. The fixed exponents allow interpretations for initial acceleration, the angle at peak torque and the decrement of torque after peak torque. Also, the multilevel models were flexible to illustrate the influence of gender differences on the shape of torque throughout the range of motion and in the shape of the curves. The presented multilevel regression models may afford a general framework to examine angle-specific moment curves by isokinetic dynamometry, and add to the understanding mechanisms of strength development, particularly the force-length relationship, both related to performance and injury prevention. PMID:26839603

  3. Validity of area-under-the-curve analysis to summarize effect in rheumatoid arthritis clinical trials.

    PubMed

    Pham, B; Cranney, A; Boers, M; Verhoeven, A C; Wells, G; Tugwell, P

    1999-03-01

    There is a continuing interest in increasing the statistical efficiency of the analysis of clinically meaningful endpoints in rheumatology. One issue that is attracting increasing attention is whether the conventional practice of only reporting the outcome at the end of the study (EOS) might be replaced or complemented by a longitudinal summary that better reflects the clinical course of the disease. The area under the curve (AUC) is a summary measure that integrates serial assessments of a patient's endpoint over the duration of the study. We evaluated the utility of AUC as a summary measure for the analysis and reporting of two RA trials: (i) methotrexate combined with cyclosporine versus methotrexate and placebo in partial methotrexate responders in relatively late disease, and (ii) prednisone plus methotrexate plus sulfasalazine versus sulfasalazine alone in relatively early disease. We replicated the published results of each trial first using the conventional EOS and then AUC summaries. For each patient, the changes from baseline over time were transformed into a summary measure by calculating AUC using the trapezium rule and then standardizing it by the study duration. Using an approach similar to the index of responsiveness to change, we scaled treatment differences derived from EOS and AUC summary measures by their standard deviation of the control group. This signal-versus-noise ratio captures the treatment discrimination ability of each summary measure. Compared to EOS and within each treatment group, the AUC summary reported smaller effects (i.e., change from baseline) with reduced errors in the estimates. AUC measures preserved discriminant validity in treatment comparisons and reported smaller but more precise treatment effect estimates. In the COBRA trial with rapidly-acting medications, AUC seemed to be more sensitive than EOS to detect treatment difference. With slow acting medications and in relatively late disease patients as in the cyclosporine trial, EOS was more sensitive to detect treatment difference than was AUC. In this setting, AUC, however, still seemed to be more sensitive than EOS for the two responsive-to-change endpoints: tender joint counts and pain by visual analog scale. AUC integrates repeated assessments during the trial duration into summary measures. Compared to EOS, the report of RA trial results using AUC summary provides smaller estimates of treatment effects but with better precision. AUC summary is likely to preserve treatment group discrimination taking into account the appropriate onset and offset of the drug action. Trial reports using AUC summary have smaller effect sizes. For trials with long acting medications and short duration similar to the cyclosporine trial, AUC still preserves treatment discrimination but may not be as sensitive as EOS. The calculations of AUC require some additional work in the analysis of each endpoint. PMID:10090188

  4. Periodicity Analysis of X-ray Light Curves of SS 433

    NASA Astrophysics Data System (ADS)

    Wang, J. Y.; Lu, X. L.; Zhao, Q. W.; Dong, D. Q.; Lao, B. Q.; Lu, Y.; Wei, Y. H.; Wu, X. C.; An, T.

    2016-03-01

    SS 433 is the only X-ray binary to date that was detected to have a pair of well-collimated jets, and its orbital period, super orbital period, and nutation period were all detected at the same time. The study on the periodic X-ray variabilities is helpful for understanding its dynamic process of the central engine and the correlation with other bands. In the present paper, two time series analysis techniques, Lomb-Scargle periodogram and weighted wavelet Z-transform, are employed to search for the periodicities from the Swift/BAT (Burst Alert Telescope)(15--50 keV) and RXTE/ASM (Rossi X-Ray Timing Explorer/All-Sky Monitor)(1.5--3, 3--5 and 5--12 keV) light curves of SS 433, and the Monte Carlo simulation is performed. For the 15--50 keV energy band, five significant periodic signals are detected, which are P_1(˜6.29 d), P_2 (˜6.54 d), P_3 (˜13.08 d), P_4 (˜81.50 d), and P_5 (˜162.30 d). For the 3--5 and 5--12 keV energy bands, periodic signals P_3 (˜13 d) and P_5 (˜162 d) are detected in both energy bands. However, for the 1.5--3 keV energy band, no significant periodic signal is detected. P_5 has the strongest periodic signal in the power spectrum for all the energy bands of 3--5, 5--12, and 15--50 keV, and it is consistent with that obtained by previous study in optical band. Further, due to the existence of relativistic radio jets, the X-ray and optical band variability of P_5 (˜162 d) is probably related to the precession of the relativistic jets. High coherence between X-ray and optical light curves may also imply that the X-ray and optical emissions are of the same physical origin. P_3 shows a good agreement with the orbital period (˜13.07 d) first obtained by previous study, and P_2 and P_4 are the high frequency harmonic components of P_3 and P_5, respectively. P_1 is detected from the power spectrum of 15--50 keV energy band only, and it is consistent with the systematic nutation period. As the power of energy band decreases (from hard X-ray to soft X-ray), less periodicities are detected, which provides an evidence that the emission from high energy band (hard X-ray) comes primarily from jets, and the emission from low energy band (soft X-ray) may originate from the medium around binary systems. The multiple X-ray periods obtained from the present studies provide the necessary basis for the analysis of multi-wavelength data and the dynamics of the central engine system of SS 433.

  5. Black hair follicular dysplasia, an autosomal recessive condition in dogs.

    PubMed Central

    Schmutz, S M; Moker, J S; Clark, E G; Shewfelt, R

    1998-01-01

    Using histology, a coat color abnormality and the subsequent hair loss were diagnosed as black hair follicular dysplasia. A pedigree analysis of an affected litter and literature review suggests that this is inherited as an autosomal recessive trait. The melanocyte stimulating hormone receptor gene is ruled out by using linkage analysis. Images Figure 1. Figure 2. PMID:9789677

  6. Enzymic characterization with progress curve analysis of a collagen peptidase from an enthomopathogenic bacterium, Photorhabdus luminescens.

    PubMed Central

    Marokházi, Judit; Kóczán, György; Hudecz, Ferenc; Gráf, László; Fodor, András; Venekei, István

    2004-01-01

    A proteolytic enzyme, Php-B ( Photorhabdus protease B), was purified from the entomopathogenic bacterium, Photorhabdus luminescens. The enzyme is intracellular, and its molecular mass is 74 kDa. Tested on various peptide and oligopeptide substrates, Php-B hydrolysed only oligopeptides, with significant activity against bradykinin and a 2-furylacryloyl-blocked peptide, Fua-LGPA (2-furylacryloyl-Leu-Gly-Pro-Ala; kcat=3.6x10(2) s(-1), K(m)=5.8x10(-5) M(-1), pH optimum approx. 7.0). The p K(a1) and the p K(a2) values of the enzyme activity (6.1 and 7.9 respectively), as well as experiments with enzyme inhibitors and bivalent metal ions, suggest that the activity of Php-B is dependent on histidine and cysteine residues, but not on serine residues, and that it is a metalloprotease, which most probably uses Zn2+ as a catalytic ion. The enzyme's ability to cleave oligopeptides that contain a sequence similar to collagen repeat (-Pro-Xaa-Gly-), bradykinin and Fua-LGPA (a synthetic substrate for bacterial collagenases and collagen peptidases), but not native collagens (types I and IV) or denatured collagen (gelatin), indicates that Php-B is probably a collagen peptidase, the first enzyme of this type to be identified in an insect pathogen, that might have a role in the nutrition of P. luminescens by degrading small collagen fragments. For the determination of enzyme kinetic constants, we fitted a numerically integrated Michaelis-Menten model to the experimental progress curves. Since this approach has not been used before in the characterization of proteases that are specific for the P1'-P4' substrate sites (e.g. collagenolytic enzymes), we present a comparison of this method with more conventional ones. The results confirm the reliability of the numerical integration method in the kinetic analysis of collagen-peptide-hydrolysing enzymes. PMID:14744262

  7. Magnetic unmixing of first-order reversal curve diagrams using principal component analysis

    NASA Astrophysics Data System (ADS)

    Lascu, Ioan; Harrison, Richard J.; Li, Yuting; Muraszko, Joy R.; Channell, James E. T.; Piotrowski, Alexander M.; Hodell, David A.

    2015-09-01

    We describe a quantitative magnetic unmixing method based on principal component analysis (PCA) of first-order reversal curve (FORC) diagrams. For PCA, we resample FORC distributions on grids that capture diagnostic signatures of single-domain (SD), pseudosingle-domain (PSD), and multidomain (MD) magnetite, as well as of minerals such as hematite. Individual FORC diagrams are recast as linear combinations of end-member (EM) FORC diagrams, located at user-defined positions in PCA space. The EM selection is guided by constraints derived from physical modeling and imposed by data scatter. We investigate temporal variations of two EMs in bulk North Atlantic sediment cores collected from the Rockall Trough and the Iberian Continental Margin. Sediments from each site contain a mixture of magnetosomes and granulometrically distinct detrital magnetite. We also quantify the spatial variation of three EM components (a coarse silt-sized MD component, a fine silt-sized PSD component, and a mixed clay-sized component containing both SD magnetite and hematite) in surficial sediments along the flow path of the North Atlantic Deep Water (NADW). These samples were separated into granulometric fractions, which helped constrain EM definition. PCA-based unmixing reveals systematic variations in EM relative abundance as a function of distance along NADW flow. Finally, we apply PCA to the combined data set of Rockall Trough and NADW sediments, which can be recast as a four-EM mixture, providing enhanced discrimination between components. Our method forms the foundation of a general solution to the problem of unmixing multicomponent magnetic mixtures, a fundamental task of rock magnetic studies.

  8. Enzymic characterization with progress curve analysis of a collagen peptidase from an enthomopathogenic bacterium, Photorhabdus luminescens.

    PubMed

    Marokházi, Judit; Kóczán, György; Hudecz, Ferenc; Gráf, László; Fodor, András; Venekei, István

    2004-05-01

    A proteolytic enzyme, Php-B ( Photorhabdus protease B), was purified from the entomopathogenic bacterium, Photorhabdus luminescens. The enzyme is intracellular, and its molecular mass is 74 kDa. Tested on various peptide and oligopeptide substrates, Php-B hydrolysed only oligopeptides, with significant activity against bradykinin and a 2-furylacryloyl-blocked peptide, Fua-LGPA (2-furylacryloyl-Leu-Gly-Pro-Ala; kcat=3.6x10(2) s(-1), K(m)=5.8x10(-5) M(-1), pH optimum approx. 7.0). The p K(a1) and the p K(a2) values of the enzyme activity (6.1 and 7.9 respectively), as well as experiments with enzyme inhibitors and bivalent metal ions, suggest that the activity of Php-B is dependent on histidine and cysteine residues, but not on serine residues, and that it is a metalloprotease, which most probably uses Zn2+ as a catalytic ion. The enzyme's ability to cleave oligopeptides that contain a sequence similar to collagen repeat (-Pro-Xaa-Gly-), bradykinin and Fua-LGPA (a synthetic substrate for bacterial collagenases and collagen peptidases), but not native collagens (types I and IV) or denatured collagen (gelatin), indicates that Php-B is probably a collagen peptidase, the first enzyme of this type to be identified in an insect pathogen, that might have a role in the nutrition of P. luminescens by degrading small collagen fragments. For the determination of enzyme kinetic constants, we fitted a numerically integrated Michaelis-Menten model to the experimental progress curves. Since this approach has not been used before in the characterization of proteases that are specific for the P1'-P4' substrate sites (e.g. collagenolytic enzymes), we present a comparison of this method with more conventional ones. The results confirm the reliability of the numerical integration method in the kinetic analysis of collagen-peptide-hydrolysing enzymes. PMID:14744262

  9. Light Curves and Analysis of the Overcontact Binaries GN Boo, V608 Cas and V789 Cyg

    NASA Astrophysics Data System (ADS)

    Sanders, S. J.; Bradstreet, D. H.; Hargis, J. R.

    2005-12-01

    New precision V & Rc light curves of the eclipsing overcontact binaries GN Boo, V608 Cas and V789 Cyg have been obtained using the 41-cm telescope at the Eastern University Observatory equipped with an SBIG ST-10XME CCD. GN Boo (P = 0.3016 days, m = 10.8) has only one published light curve (Blattler & Diethelm 2001a) which is noisy and had no subsequent analysis. The system was observed on 5 nights from 3 - 14 Mar 2005, accumulating approximately 750 observations in both V and Rc. Because the previously published light curve had rather large excursions in light, it was hoped that GN Boo would display total eclipses, which in fact it does. Preliminary analysis indicates that it has a mass ratio of q = 0.33, a temperature difference of 360 K between the two components, and a fillout f = 0.21. The maxima are markedly asymmetric which was modeled with a cool spot region. V608 Cas (P = 0.3804 days, m = 12.0) was observed by Blattler & Diethelm (2001b) who published a complete but noisy light curve. Although chosen for study because its published light curve suggested possible totality in the eclipses, this did not turn out to be the case. V608 Cas was observed on 3 nights from 18 Oct - 7 Nov 2004, accumulating approximately 560 observations in both V and Rc. Preliminary light curve models indicate an overcontact system with a small temperature difference between the two stars of approximately 200 K and a fillout f = 0.25. V789 Cyg (P = 0.4483, m = 13.3) is classified in the GCVS as an RR Lyrae variable, and the system was presented as such by Ponce & Sharp (2000). However their light curve looked to us very much like a W UMa light curve folded upon itself with half the true period, and so this system was observed in V and Rc on 8 nights from 27 Jun - 21 Jul 2004. The resulting light curves confirmed the overcontact nature of the system, and the modeling is still in progress. The final results of the analyses of these systems will be presented.

  10. Analysis of late-time light curves of Type IIb, Ib and Ic supernovae

    NASA Astrophysics Data System (ADS)

    Wheeler, J. Craig; Johnson, V.; Clocchiatti, A.

    2015-06-01

    The shape of the light-curve peak of radioactive-powered core-collapse `stripped-envelope' supernovae constrains the ejecta mass, nickel mass and kinetic energy by the brightness and diffusion time for a given opacity and observed expansion velocity. Late-time light curves give constraints on the ejecta mass and energy, given the gamma-ray opacity. Previous work has shown that the principal light-curve peaks for SN IIb with small amounts of hydrogen and for hydrogen/helium-deficient SN Ib/c are often rather similar near maximum light, suggesting similar ejecta masses and kinetic energies, but that late-time light curves show a wide dispersion, suggesting a dispersion in ejecta masses and kinetic energies. It was also shown that SN IIb and SN Ib/c can have very similar late-time light curves, but different ejecta velocities demanding significantly different ejecta masses and kinetic energies. We revisit these topics by collecting and analysing well-sampled single-band and quasi-bolometric light curves from the literature. We find that the late-time light curves of stripped-envelope core-collapse supernovae are heterogeneous. We also show that the observed properties, the photospheric velocity at peak, the rise time and the late decay time, can be used to determine the mean opacity appropriate to the peak. The opacity determined in this way is considerably smaller than common estimates. We discuss how the small effective opacity may result from recombination and asymmetries in the ejecta.

  11. Combined statistical analysis of vasodilation and flow curves in brachial ultrasonography: technique and its connection to cardiovascular risk factors

    NASA Astrophysics Data System (ADS)

    Boisrobert, Loic; Laclaustra, Martin; Bossa, Matias; Frangi, Andres G.; Frangi, Alejandro F.

    2005-04-01

    Clinical studies report that impaired endothelial function is associated with Cardio-Vascular Diseases (CVD) and their risk factors. One commonly used mean for assessing endothelial function is Flow-Mediated Dilation (FMD). Classically, FMD is quantified using local indexes e.g. maximum peak dilation. Although such parameters have been successfully linked to CVD risk factors and other clinical variables, this description does not consider all the information contained in the complete vasodilation curve. Moreover, the relation between flow impulse and the vessel vasodilation response to this stimulus, although not clearly known, seems to be important and is not taken into account in the majority of studies. In this paper we propose a novel global parameterization for the vasodilation and the flow curves of a FMD test. This parameterization uses Principal Component Analysis (PCA) to describe independently and jointly the variability of flow and FMD curves. These curves are obtained using computerized techniques (based on edge detection and image registration, respectively) to analyze the ultrasound image sequences. The global description obtained through PCA yields a detailed characterization of the morphology of such curves allowing the extraction of intuitive quantitative information of the vasodilation process and its interplay with flow changes. This parameterization is consistent with traditional measurements and, in a database of 177 subjects, seems to correlate more strongly (and with more clinical parameters) than classical measures to CVD risk factors and clinical parameters such as LDL- and HDL-Cholesterol.

  12. Does the Budyko curve reflect a maximum-power state of hydrological systems? A backward analysis

    NASA Astrophysics Data System (ADS)

    Westhoff, M.; Zehe, E.; Archambeau, P.; Dewals, B.

    2016-01-01

    Almost all catchments plot within a small envelope around the Budyko curve. This apparent behaviour suggests that organizing principles may play a role in the evolution of catchments. In this paper we applied the thermodynamic principle of maximum power as the organizing principle. In a top-down approach we derived mathematical formulations of the relation between relative wetness and gradients driving run-off and evaporation for a simple one-box model. We did this in an inverse manner such that, when the conductances are optimized with the maximum-power principle, the steady-state behaviour of the model leads exactly to a point on the asymptotes of the Budyko curve. Subsequently, we added dynamics in forcing and actual evaporation, causing the Budyko curve to deviate from the asymptotes. Despite the simplicity of the model, catchment observations compare reasonably well with the Budyko curves subject to observed dynamics in rainfall and actual evaporation. Thus by constraining the model that has been optimized with the maximum-power principle with the asymptotes of the Budyko curve, we were able to derive more realistic values of the aridity and evaporation index without any parameter calibration. Future work should focus on better representing the boundary conditions of real catchments and eventually adding more complexity to the model.

  13. Management of the Spring Snowmelt Recession in Regulated Systems

    NASA Astrophysics Data System (ADS)

    Yarnell, S. M.; Lind, A.; Epke, G.; Viers, J. H.

    2013-12-01

    In unregulated rivers in the Sierra Nevada mountains of California, the spring snowmelt recession links high winter flows to low summer baseflow and is a consistent and predictable portion of the annual hydrograph. Consequently, it is an important resource to both riverine ecosystems and California's water supply. In regulated river systems where the spring snowmelt recession is often captured behind dams or diverted for hydropower, restoration of a more natural spring flow regime can provide distinct ecological benefits, such as breeding and migration cues for native species, increased habitat availability, and greater hydraulic habitat diversity. However, knowledge of how to create and manage an ecologically beneficial spring snowmelt recession in a regulated river system has been lacking. This study defined a methodology by which spring flow regimes can be modeled in regulated systems from the quantifiable characteristics of spring snowmelt recessions in unregulated rivers. Using fundamental flow components such as magnitude, timing, and rate of change, the spring snowmelt recession in eight unregulated rivers across the Sierra Nevada range was quantified to gain a better understanding of the predictability and variability across watersheds. The analysis found that unregulated Sierran systems behaved similarly with respect to seasonal patterns and flow recession shape (i.e., recession limb curvature), and thus flows could be modeled in a manner that mimics those predictable characteristics. Using this methodology that quantifies spring recession flows in terms of a daily percent decrease in flow, a series of flow recession scenarios were then created for application on a regulated Sierran river. Four scenarios, ranging from a slow natural recession to a short fast recession typically observed in regulated rivers following cessation of high flow spills, were evaluated within a 2D hydrodynamic model. The effects of the flows on suitable habitat for Foothill yellow-legged frogs, a California species of special concern, were evaluated, and the distribution and diversity of hydraulic habitat through time was assessed. Using a spatial niche approach, the hydraulic habitat conditions were considered with regard to native aquatic species guilds, and the effects of each flow scenario on aquatic biodiversity were determined. The modeling results show that flow recessions with slow ramping rates similar to those observed in unregulated systems (less than 10% per day) were protective of frog egg masses, while flows that receded at rates greater than 10% per day resulted in desiccation of egg masses and potential stranding of newly hatched tadpoles. Furthermore, recession rates of less than 10% per day provided the most diverse hydraulic habitat for an appropriate duration in spring to support all native species guilds and maximize aquatic biodiversity. The predictive flow model described in this study has recently been applied within the Federal Energy Regulatory Commission hydropower relicensing process on the Yuba River to create flow recessions that more naturally transition from high spill flows to minimum instream flows, and is readily adaptable to other snowmelt regions with knowledge of regional unregulated flow characteristics.

  14. Analysis of light curves and apsidal motion of neglected southern eclipsing binary V399 Pup

    NASA Astrophysics Data System (ADS)

    Bulut, İ.; Bulut, A.; Çiçek, C.

    2014-10-01

    In this study, the Hipparcos and ASAS light curves of the eclipsing binary V399 Pup have been analyzed using the Wilson-Devinney program. The light curve analyses have found that V399 Pup is a detached binary system with eccentric orbit. The apsidal motion parameters of the system have been obtained from the O-C curve analyses. The system has been revealed to have an orbital eccentricity of e = 0.145 ± 0.006, the apsidal motion rate has been obtained ω ˙ = 0.0385 ± 0.0069 deg cycle-1, and it corresponds to an apsidal motion period of U = 100.2 ± 18.0 years.

  15. Hierarchical Bayesian Modeling and Markov Chain Monte Carlo Sampling for Tuning-Curve Analysis

    PubMed Central

    Cronin, Beau; Sur, Mriganka; Körding, Konrad P.

    2010-01-01

    A central theme of systems neuroscience is to characterize the tuning of neural responses to sensory stimuli or the production of movement. Statistically, we often want to estimate the parameters of the tuning curve, such as preferred direction, as well as the associated degree of uncertainty, characterized by error bars. Here we present a new sampling-based, Bayesian method that allows the estimation of tuning-curve parameters, the estimation of error bars, and hypothesis testing. This method also provides a useful way of visualizing which tuning curves are compatible with the recorded data. We demonstrate the utility of this approach using recordings of orientation and direction tuning in primary visual cortex, direction of motion tuning in primary motor cortex, and simulated data. PMID:19889855

  16. Analysis of a Kepler Light Curve of the Novalike Cataclysmic Variable KIC 8751494

    NASA Astrophysics Data System (ADS)

    Kato, Taichi; Maehara, Hiroyuki

    2013-08-01

    We analyzed a Kepler light curve of KIC 8751494, a recently recognized novalike cataclysmic variable in the Kepler field. We detected a stable periodicity of 0.114379(1) d, which we identified as being the binary's orbital period. The stronger photometric period at around 0.12245 d, which had been detected from a ground-based observation, was found to be variable, and we identified this period as the positive-superhump period. This superhump period showed short-term (10-20 d) strong variations in period most unexpectedly when the object entered a slightly faint state. The fractional superhump excess varied by as much large as ˜ 30%. The variation of the period very well traced the variation of the brightness of the system. The time-scale of this variation of superhump periods was too slow to be interpreted as a variation caused by a change of the disk radius due to thermal disk instability. We interpreted the cause of the period variation as a varying pressure effect on the period of positive superhumps. This finding suggests that the pressure effect, in at least novalike systems, plays a very important (up to ˜ 30% in the precession rate) role in producing the period of positive superhumps. We also described a possible detection of negative superhumps with a varying period of 0.1071-0.1081 d in the Q14 run of the Kepler data, and found that the variation of frequency of negative superhumps followed that of positive superhumps. The relation between the fractional superhump excesses of negative and positive superhumps can be understood if the angular frequency of positive superhumps is decreased by a pressure effect. We also found that the phase of the variation in the velocity of the emission lines reported in the earlier study is compatible with the SW Sex-type classification. Further, we introduced a new two-dimentional period analysis using least absolute shrinkage and selection operator (Lasso), and showed superior advantages of this method.

  17. The trauma of a recession.

    PubMed

    Murphy, S M; Kieran, I; Shaughnessy, M O

    2011-09-01

    Employment in construction in Ireland fell by 10% from nearly 282,000 in the second quarter of 2007 to 255,000 in the same period of 2008. Our study looks at the differences in soft tissue upper limb trauma dynamics of a pre- and post-recession Ireland. Construction accounted for 330 patients (27%) of all hand injuries in 2006, but only 18 (3%) in 2009. Our data shows a significant drop in hand injuries related to the construction industry, and more home/DIY cases and deliberate self-harm presenting in their stead. PMID:21431394

  18. The Latent Curve ARMA (P, Q) Panel Model: Longitudinal Data Analysis in Educational Research and Evaluation

    ERIC Educational Resources Information Center

    Sivo, Stephen; Fan, Xitao

    2008-01-01

    Autocorrelated residuals in longitudinal data are widely reported as common to longitudinal data. Yet few, if any, researchers modeling growth processes evaluate a priori whether their data have this feature. Sivo, Fan, and Witta (2005) found that not modeling autocorrelated residuals present in longitudinal data severely biases latent curve

  19. Parent Involvement and Science Achievement: A Cross-Classified Multilevel Latent Growth Curve Analysis

    ERIC Educational Resources Information Center

    Johnson, Ursula Y.; Hull, Darrell M.

    2014-01-01

    The authors examined science achievement growth at Grades 3, 5, and 8 and parent school involvement at the same time points using the Early Childhood Longitudinal Study-Kindergarten Class of 1998-1999. Data were analyzed using cross-classified multilevel latent growth curve modeling with time invariant and varying covariates. School-based…

  20. Applications of species accumulation curves in large-scale biological data analysis

    PubMed Central

    Deng, Chao; Daley, Timothy; Smith, Andrew D

    2016-01-01

    The species accumulation curve, or collector’s curve, of a population gives the expected number of observed species or distinct classes as a function of sampling effort. Species accumulation curves allow researchers to assess and compare diversity across populations or to evaluate the benefits of additional sampling. Traditional applications have focused on ecological populations but emerging large-scale applications, for example in DNA sequencing, are orders of magnitude larger and present new challenges. We developed a method to estimate accumulation curves for predicting the complexity of DNA sequencing libraries. This method uses rational function approximations to a classical non-parametric empirical Bayes estimator due to Good and Toulmin [Biometrika, 1956, 43, 45–63]. Here we demonstrate how the same approach can be highly effective in other large-scale applications involving biological data sets. These include estimating microbial species richness, immune repertoire size, and k-mer diversity for genome assembly applications. We show how the method can be modified to address populations containing an effectively infinite number of species where saturation cannot practically be attained. We also introduce a flexible suite of tools implemented as an R package that make these methods broadly accessible.

  1. Discrimination of photon from proton irradiation using glow curve feature extraction and vector analysis.

    PubMed

    Skopec, M; Loew, M; Price, J L; Guardala, N; Moscovitch, M

    2006-01-01

    Two types of thermoluminescence dosemeters (TLDs), the Harshaw LiF:Mg,Ti (TLD-100) and CaF(2):Tm (TLD-300) were investigated for their glow curve response to separate photon and proton irradiations. The TLDs were exposed to gamma irradiation from a (137)Cs source and proton irradiation using a positive ion accelerator. The glow curve peak structure for each individual TLD exposure was deconvolved to obtain peak height, width, and position. Simulated mixed-field glow curves were obtained by superposition of the experimentally obtained single field exposures. Feature vectors were composed of two kinds of features: those from deconvolution and those taken in the neighbourhood of several glow curve peaks. The inner product of the feature vectors was used to discriminate among the pure photon, pure proton and simulated mixed-field irradiations. In the pure cases, identification of radiation types is both straightforward and effective. Mixed-field discrimination did not succeed using deconvolution features, but the peak-neighbourhood features proved to discriminate reliably. PMID:16614091

  2. The Dynamics of Self-Esteem: A Growth-Curve Analysis.

    ERIC Educational Resources Information Center

    Baldwin, Scott A.; Hoffmann, John P.

    2002-01-01

    Using 7 years of sequential data from the Family Health Study for 762 subjects aged 11 to 16 years in year 1, estimated a hierarchical growth curve model that emphasized the effects of age, life events, gender, and family cohesion on self-esteem. Results show a curvilinear relationship between age and self-esteem, suggesting that self-esteem is a…

  3. Analysis of hyperspherical adiabatic curves of helium: A classical dynamics study

    NASA Astrophysics Data System (ADS)

    Simonović, N. S.; Solov'ev, E. A.

    2013-05-01

    The hyperspherical adiabatic curves (adiabatic eigenenergies as functions of the hyperradius R) of helium for zero total angular momentum are analyzed by studying the underlying classical dynamics which in the adiabatic treatment reduces to constrained two-electron motion on a hypersphere. This dynamics supports five characteristic classical configurations which can be represented by five types of short periodic orbits: the frozen planet (FP), the inverted frozen planet (IFP), the asymmetric stretch (AS), the asynchronous (ASC), and the Langmuir periodic orbit (PO). These POs are considered as fundamental modes of the two-electron motion on a hypersphere which, after quantization, give five families of so-called adiabatic lines (adiabatic energies related to these POs as functions of R). It is found that multiplets, each of them consisting of adiabatic curves which converge to the same ionization threshold, are at large values of R delimited from the bottom and from the top by the adiabatic lines which are related to the IFP and stable AS POs and to the FP PO, respectively. At smaller values of R, where the AS PO becomes unstable, the curves move to the area between the ASC (bottom) and AS (top) lines by crossing the latter. Therefore, at different values of R the lower limiting line of the multiplet is related to the three types of PO (IFP, AS, and ASC), which are all stable in the negative-energy part of this line. As a consequence, the quantum states of helium in principle are not related individually to a single classical configuration on the hypersphere. In addition, it is demonstrated that “unstable parts” of adiabatic lines (the so-called diabatic curves) determine the positions and type of avoided and hidden crossings between hyperspherical adiabatic curves. Two clearly visible classes of avoided crossings are related to the AS and ASC POs. In addition, a number of avoided crossings of the adiabatic curves is observed at the positions where the adiabatic lines that are related to different types of PO cross mutually. Finally, a class of hidden crossings which is located near the saddle point of the potential is related to the Langmuir orbit. The large spacing between adiabatic curves at the positions of these hidden crossings is explained by high instability of the Langmuir PO compared to the AS and ASC POs.

  4. Noise transmission from a curved panel into a cylindrical enclosure: analysis of structural acoustic coupling.

    PubMed

    Henry, J K; Clark, R L

    2001-04-01

    Much of the research on sound transmission through the aircraft fuselage into the interior of aircraft has considered coupling of the entire cylinder to the acoustic modes of the enclosure. Yet, much of the work on structural acoustic control of sound radiation has focused on reducing sound radiation from individual panels into an acoustic space. Research by the authors seeks to bridge this gap by considering the transmission of sound from individual panels on the fuselage to the interior of the aircraft. As part of this research, an analytical model of a curved panel, with attached piezoelectric actuators, subjected to a static pressure load was previously developed. In the present work, the analytical model is extended to consider the coupling of a curved panel to the interior acoustics of a rigid-walled cylinder. Insight gained from an accurate analytical model of the dynamics of the noise transmission from the curved panels of the fuselage into the cylindrical enclosure of an aircraft is essential to the development of feedback control systems for the control of stochastic inputs, such as turbulent boundary layer excitation. The criteria for maximal structural acoustic coupling between the modes of the curved panel and the modes of the cylindrical enclosure are studied. For panels with aspect ratios typical of those found in aircraft, results indicate that predominately axial structural modes couple most efficiently to the acoustic modes of the enclosure. The effects of the position of the curved panel on the cylinder are also studied. Structural acoustic coupling is found to not be significantly affected by varying panel position. The impact of the findings of this study on structural acoustic control design is discussed. PMID:11325117

  5. A LIGHT CURVE ANALYSIS OF CLASSICAL NOVAE: FREE-FREE EMISSION VERSUS PHOTOSPHERIC EMISSION

    SciTech Connect

    Hachisu, Izumi; Kato, Mariko E-mail: mariko@educ.cc.keio.ac.jp

    2015-01-10

    We analyzed light curves of seven relatively slower novae, PW Vul, V705 Cas, GQ Mus, RR Pic, V5558 Sgr, HR Del, and V723 Cas, based on an optically thick wind theory of nova outbursts. For fast novae, free-free emission dominates the spectrum in optical bands rather than photospheric emission, and nova optical light curves follow the universal decline law. Faster novae blow stronger winds with larger mass-loss rates. Because the brightness of free-free emission depends directly on the wind mass-loss rate, faster novae show brighter optical maxima. In slower novae, however, we must take into account photospheric emission because of their lower wind mass-loss rates. We calculated three model light curves of free-free emission, photospheric emission, and their sum for various white dwarf (WD) masses with various chemical compositions of their envelopes and fitted reasonably with observational data of optical, near-IR (NIR), and UV bands. From light curve fittings of the seven novae, we estimated their absolute magnitudes, distances, and WD masses. In PW Vul and V705 Cas, free-free emission still dominates the spectrum in the optical and NIR bands. In the very slow novae, RR Pic, V5558 Sgr, HR Del, and V723 Cas, photospheric emission dominates the spectrum rather than free-free emission, which makes a deviation from the universal decline law. We have confirmed that the absolute brightnesses of our model light curves are consistent with the distance moduli of four classical novae with known distances (GK Per, V603 Aql, RR Pic, and DQ Her). We also discussed the reason why the very slow novae are about ∼1 mag brighter than the proposed maximum magnitude versus rate of decline relation.

  6. Generalized semi-analytical finite difference method for dispersion curves calculation and numerical dispersion analysis for Lamb waves.

    PubMed

    Packo, Pawel; Uhl, Tadeusz; Staszewski, Wieslaw J

    2014-09-01

    The paper presents an efficient and accurate method for dispersion curve calculation and analysis of numerical models for guided waves. The method can be used for any arbitrarily selected anisotropic material. The proposed approach utilizes the wave equation and through-thickness-only discretization of anisotropic, layered plates to obtain the Lamb wave characteristics. Thus, layered structures, such as composites, can be analyzed in a straightforward manner. A general framework for the proposed analysis is given, along with application examples. Although these examples are based on the local interaction simulation approach for elastic waves propagation, the proposed methodology can be easily adopted for other methods (e.g., finite elements). The method can be also used to study the influence of discretization parameters on dispersion curves estimates. PMID:25190375

  7. Mapping of local cerebral blood flow with stable xenon-enhanced CT and the curve-fitting method of analysis

    SciTech Connect

    Touho, H.; Karasawa, J.; Nakagawara, J.; Tazawa, T.; Yamada, K.; Kuriyama, Y.; Asai, M.; Kagawa, M.; Kobayashi, K.; Yasue, H.

    1988-07-01

    A noninvasive method is described for estimating local cerebral blood flow (LCBF) and local partition coefficients by means of computed tomographic scanning during inhalation of 30% stable xenon gas in oxygen. Time-dependent xenon concentrations in arterial blood and brain tissue during the wash-in and washout phases are used to calculate partition coefficients and LCBF values by means of a least-squares curve-fitting analysis. Control values for partition coefficient and LCBF obtained from control subjects with minor head trauma in the chronic stage were compatible with those in several past reports, and reproducibility was satisfactory. The theoretic grounds underlying this new method of curve-fitting analysis are discussed.

  8. Prenatal diagnosis for recessive dystrophic epidermolysis bullosa in 10 families by mutation and haplotype analysis in the type VII collagen gene (COL7A1).

    PubMed Central

    Christiano, A. M.; LaForgia, S.; Paller, A. S.; McGuire, J.; Shimizu, H.; Uitto, J.

    1996-01-01

    BACKGROUND: Epidermolysis bullosa (EB) is a group of heritable diseases that manifest as blistering and erosions of the skin and mucous membranes. In the dystrophic forms of EB (DEB), the diagnostic hallmark is abnormalities in the anchoring fibrils, attachment structures beneath the cutaneous basement membrane zone. The major component of anchoring fibrils is type VII collagen, and DEB has been linked to the type VII collagen gene (COL7A1) at 3p21, with no evidence for locus heterogeneity. Due to life-threatening complications and significant long-term morbidity associated with the severe, mutilating form of recessive dystrophic EB (RDEB), there has been a demand for prenatal diagnosis from families with affected offspring. MATERIALS AND METHODS: Intragenic polymorphisms in COL7A1 and flanking microsatellite markers on chromosome 3p21, as well as detection of pathogenetic mutations in families, were used to perform PCR-based prenatal diagnosis from DNA obtained by chorionic villus sampling at 10-15 weeks or amniocentesis at 12-15 weeks gestation in 10 families at risk for recurrence of RDEB. RESULTS: In nine cases, the fetus was predicted to be normal or a clinically unaffected carrier of a mutation in one allele. These predictions have been validated in nine cases by the birth of a healthy child. In one case, an affected fetus was predicted, and the diagnosis was confirmed by fetal skin biopsy. CONCLUSIONS: DNA-based prenatal diagnosis of RDEB offers an early, expedient method of testing which will largely replace the previously available invasive fetal skin biopsy at 18-20 weeks gestation. Images FIG. 1 FIG. 3 PMID:8900535

  9. Bank recession processes, rates, and prediction, Lake Sakakawea, North Dakota, U.S.A.

    NASA Astrophysics Data System (ADS)

    Reid, John R.; Sandberg, Brian S.; Millsop, Mark D.

    1988-03-01

    Bank recession at twenty stations along the eastern end of 286 km long Lake Sakakawea, North Dakota, measured regularly between 1983 and 1986, showed a recession range from essentially zero to almost 9 m yr -1 with an average of 1.6 m yr -1. Between 1969 and 1979, rates were greater, the declining rate a normal consequence of the factors affecting bank recession. Rates of recession vary with seasons, with 78% of the annual recession occurring during the warmer season (May-October) as a result of wave erosion. The remaining 22% occurs during thaw failure in spring. Prediction of ultimate (500 yr) bank recessions attempted using historical recession data, the three years of detailed field measurements, and regression analysis of the erosion factors. An equation, presented here, requires field measurement of bank orientation and height, batch width and composition, and slope of the offshore area. Effective fetch must be measured, as well. The resulting equation for the monthly warm season recession rate is: Rs=154.9 -, (18.8 √ A+ 25.1 √ B +10.1 √ c +6.9 √ 0+5.0 √ E + 1.1 √ F) where: A = sine of angle between bank orientation and dominant wind; B = offshore slope angle; C = beach width; D = bank height; E = effective fetch; and F = percentage of coarse beach clasts. The colder season recession percentage is: Rw = Rs [(2.05 D = 0.043 G) - 2/100] where D is bank height and G the bank orientation with respect to sun. The total yearly predicted recession (cm yr -1) is: Rt = 6 ( Rw) + 6 ( Rs) 6 being the number of months of "cold" and "warm" weather at Lake Sakakawea. For this rate to be projected into the future, it is necessary to assume a declining rate of recession, employing a parabolic trend. From this, the ultimate bank recession for Lake Sakakawea is predicted to range up to 542 m.

  10. Quantum Curves

    NASA Astrophysics Data System (ADS)

    Schwarz, Albert

    2015-08-01

    One says that a pair ( P, Q) of ordinary differential operators specify a quantum curve if . If a pair of difference operators ( K, L) obey the relation KL = q LK, where , we say that they specify a discrete quantum curve. This terminology is prompted by well known results about commuting differential and difference operators, relating pairs of such operators with pairs of meromorphic functions on algebraic curves obeying some conditions. The goal of this paper is to study the moduli spaces of quantum curves. We will relate the moduli spaces for different . We will show how to quantize a pair of commuting differential or difference operators (i.e., to construct the corresponding quantum curve or discrete quantum curve).

  11. The Effects of Four Decades of Recession on Higher Education Enrollments in the United States

    ERIC Educational Resources Information Center

    Wright, Dianne A.; Ramdin, Gianna; Vásquez-Colina, María D.

    2013-01-01

    The United States experienced six economic recessions between 1970 and 2009. The impact of economic recession on higher education enrollment was examined using seasonally adjusted data from the U.S. Census and the U.S. Department of Labor Bureau of Labor Statistics, Unemployment Level-Civilian Labor Force. One-way analysis of variance, factorial…

  12. Recession, Retrenchment, and Recovery: State Higher Education Funding & Student Financial Aid. Volume II: State Profiles

    ERIC Educational Resources Information Center

    Ambrose, Allison S.; Hines, Edward R.; Hodel, Ross A.; Kelly, Kathleen F.; Mushrush, Christopher E., Pruden, Sheila J.; Vogt, W. Paul

    2006-01-01

    This report is a companion to "Recession, Retrenchment and Recovery: Higher Education Funding and Student Financial Aid" (ED502180). It provides profiles of individual states and their performance on a variety of measures used in the economic and fiscal analysis of the Recession, Retrenchment and Recovery project. The profiles describe the results…

  13. Highlights and pitfalls of 20 years of application of computerised glow curve analysis to thermoluminescence research and dosimetry.

    PubMed

    Horowitz, Y S; Moscovitch, M

    2013-01-01

    The technical and dosimetric aspects of computerised glow curve analysis are described in detail including a review of the current 'state-of-the-achieved' in applications to environmental and personal dosimetry, clinical dosimetry, quality control, characterisation of new materials, continuing characterisation of 'old' materials, heavy charged particle dosimetry, mixed field n-gamma dosimetry, X-ray dosimetry and other aspects of thermoluminescence dosimetry. Fearless emphasis is placed on 'pitfalls' as well as successes. PMID:22987121

  14. Open-Mode Debonding Analysis of Curved Sandwich Panels Subjected to Heating and Cryogenic Cooling on Opposite Faces

    NASA Technical Reports Server (NTRS)

    Ko, William L.

    1999-01-01

    Increasing use of curved sandwich panels as aerospace structure components makes it vital to fully understand their thermostructural behavior and identify key factors affecting the open-mode debonding failure. Open-mode debonding analysis is performed on a family of curved honeycomb-core sandwich panels with different radii of curvature. The curved sandwich panels are either simply supported or clamped, and are subjected to uniform heating on the convex side and uniform cryogenic cooling on the concave side. The finite-element method was used to study the effects of panel curvature and boundary condition on the open-mode stress (radial tensile stress) and displacement fields in the curved sandwich panels. The critical stress point, where potential debonding failure could initiate, was found to be at the midspan (or outer span) of the inner bonding interface between the sandwich core and face sheet on the concave side, depending on the boundary condition and panel curvature. Open-mode stress increases with increasing panel curvature, reaching a maximum value at certain high curvature, and then decreases slightly as the panel curvature continues to increase and approach that of quarter circle. Changing the boundary condition from simply supported to clamped reduces the magnitudes of open-mode stresses and the associated sandwich core depth stretching.

  15. Relationships between each part of the spinal curves and upright posture using Multiple stepwise linear regression analysis.

    PubMed

    Boulet, Sebastien; Boudot, Elsa; Houel, Nicolas

    2016-05-01

    Back pain is a common reason for consultation in primary healthcare clinical practice, and has effects on daily activities and posture. Relationships between the whole spine and upright posture, however, remain unknown. The aim of this study was to identify the relationship between each spinal curve and centre of pressure position as well as velocity for healthy subjects. Twenty-one male subjects performed quiet stance in natural position. Each upright posture was then recorded using an optoelectronics system (Vicon Nexus) synchronized with two force plates. At each moment, polynomial interpolations of markers attached on the spine segment were used to compute cervical lordosis, thoracic kyphosis and lumbar lordosis angle curves. Mean of centre of pressure position and velocity was then computed. Multiple stepwise linear regression analysis showed that the position and velocity of centre of pressure associated with each part of the spinal curves were defined as best predictors of the lumbar lordosis angle (R(2)=0.45; p=1.65*10-10) and the thoracic kyphosis angle (R(2)=0.54; p=4.89*10-13) of healthy subjects in quiet stance. This study showed the relationships between each of cervical, thoracic, lumbar curvatures, and centre of pressure's fluctuation during free quiet standing using non-invasive full spinal curve exploration. PMID:26970888

  16. Fracture toughness master-curve analysis of the tempered martensitic steel Eurofer97

    NASA Astrophysics Data System (ADS)

    Mueller, Pablo; Spätig, P.; Bonadé, R.; Odette, G. R.; Gragg, D.

    2009-04-01

    We report fracture toughness data for the reduced activation tempered martensitic steel Eurofer97 in the lower to middle transition region. The fracture toughness was measured from tests carried out on 0.35 T and 0.87 T pre-cracked compact tension specimens. The data were first analyzed using the ASTM E1921 standard. The toughness-temperature behavior and scatter were shown to deviate from the ASTM E1921 standard predictions near the lower shelf. Using the method of maximum likelihood, the athermal component of the master-curve was calculated to better fit the data from the lower to the middle transition region. We showed that these master-curve adjustments are necessary to make the To values obtained near the lower shelf with 0.35 TC( T) specimens consistent with those obtained in the middle transition region with 0.87 TC( T) specimens.

  17. Fitting sediment rating curves using regression analysis: a case study of Russian Arctic rivers

    NASA Astrophysics Data System (ADS)

    Tananaev, N. I.

    2015-03-01

    Published suspended sediment data for Arctic rivers is scarce. Suspended sediment rating curves for three medium to large rivers of the Russian Arctic were obtained using various curve-fitting techniques. Due to the biased sampling strategy, the raw datasets do not exhibit log-normal distribution, which restricts the applicability of a log-transformed linear fit. Non-linear (power) model coefficients were estimated using the Levenberg-Marquardt, Nelder-Mead and Hooke-Jeeves algorithms, all of which generally showed close agreement. A non-linear power model employing the Levenberg-Marquardt parameter evaluation algorithm was identified as an optimal statistical solution of the problem. Long-term annual suspended sediment loads estimated using the non-linear power model are, in general, consistent with previously published results.

  18. Eigen analysis of tree-ring records: Part 1, a limited representativeness of regional curve

    NASA Astrophysics Data System (ADS)

    Yang, Bao; Sonechkin, Dmitry M.; Datsenko, Nina M.; Ivashchenko, Nadezda N.; Liu, Jingjing; Qin, Chun

    2011-12-01

    Based on a set of very long-living (2,000 years) Qilian junipers ( Sabina przewalskii Kom.) from the north-eastern part of the Tibetan Plateau (the region of Dulan), we carefully consider the regional curve standardization (RCS) technique. For this goal, we correlate deviations of individual tree-ring width records from their regional mean age-dependent curve (RC). It turns out that these correlations keep their positivity for almost all shifts between ages compared (up to 500 years and even more) evidencing each Dulan juniper to be a unique "thermometer". Just the unification of these "thermometers" in the form RC creates a spurious positive trend in the Dulan chronology. We modify the RCS technique to closer attach RC to these "thermometers" in order to construct a new chronology in which the trend is absent.

  19. Analysis of the early spectra and light curve of SN 1987A

    NASA Technical Reports Server (NTRS)

    Hauschildt, Peter H.; Ensman, Lisa M.

    1994-01-01

    Numerical modeling of supernova spectra, light curves, and hydrodynamics requires physical inputs, numerical techniques, approximations, and assumptions which must be thoroughly understood in order to study the details of supernova explosions. Here, we discuss some of these in the context of the early evolution of supernova 1987A. Gray radiation-hydrodynamics is used to calculate the bolometric light curve and the hydrodynamic evolution of the supernova. Synthetic spectra are then obtained for the resulting density and velocity structure. The spectrum calculations are performed using a special-relativistic treatment of the radiative transfer equation in the comoving frame, line blanketing by about 10(exp 5) spectral lines, and departures from local thermodynamic equilibrium (LTE) for H I, He I, Mg II, and Ca II. We find that we are able to simultaneously fit the early light curve and spectra reasonably well, using a progenitor model from Arnett (1991a), without fine-tuning the free parameters. Temperature structures and radiative equilibrium, non-LTE effects, homologous expansion, and mean opacities are discussed.

  20. A light curve and its analysis of Type Ia SN 1604

    NASA Astrophysics Data System (ADS)

    Lee, Eun Hee; Lee, Dae-Young; Mihn, Byeong-Hee

    2015-08-01

    SN 1604, known as Kepler’s supernova, was first detected by European observers, but a full light curve including its peak brightness and initial decline part can only be completed by extra data from Korean royal astronomers of four centuries ago. Nowadays, it is considered one of the Type Ia galactic supernovae, which show the empirical correlation between decline rate and peak luminosity - so called Phillips relation or width-luminosity (W-L) relation. Here, we reconstruct a new light curve based on both the Korean and European records of SN 1604. Using this light curve and W-L relation, we present an observed rise time and decline rates after peak, and derive its absolute peak magnitude and distance. In this study, observed rise time (≈ 19±1 days) shows a good agreement with typical mean time of Type Ia SNe, while the initial decline rates such as Δm15(V) and Δm20(V) represent steeper and faster values than the extra-galactic SNe Ia. Moreover, its absolute peak magnitude and distance derived from the W-L relation show much fainter and nearer values, respectively than the estimated results by different methods

  1. CONFIRMATION OF HOT JUPITER KEPLER-41b VIA PHASE CURVE ANALYSIS

    SciTech Connect

    Quintana, Elisa V.; Rowe, Jason F.; Caldwell, Douglas A.; Christiansen, Jessie L.; Jenkins, Jon M.; Morris, Robert L.; Smith, Jeffrey C.; Thompson, Susan E.; Barclay, Thomas; Ciardi, David R.; Klaus, Todd C.

    2013-04-20

    We present high precision photometry of Kepler-41, a giant planet in a 1.86 day orbit around a G6V star that was recently confirmed through radial velocity measurements. We have developed a new method to confirm giant planets solely from the photometric light curve, and we apply this method herein to Kepler-41 to establish the validity of this technique. We generate a full phase photometric model by including the primary and secondary transits, ellipsoidal variations, Doppler beaming, and reflected/emitted light from the planet. Third light contamination scenarios that can mimic a planetary transit signal are simulated by injecting a full range of dilution values into the model, and we re-fit each diluted light curve model to the light curve. The resulting constraints on the maximum occultation depth and stellar density combined with stellar evolution models rules out stellar blends and provides a measurement of the planet's mass, size, and temperature. We expect about two dozen Kepler giant planets can be confirmed via this method.

  2. Statistically generated weighted curve fit of residual functions for modal analysis of structures

    NASA Technical Reports Server (NTRS)

    Bookout, P. S.

    1995-01-01

    A statistically generated weighting function for a second-order polynomial curve fit of residual functions has been developed. The residual flexibility test method, from which a residual function is generated, is a procedure for modal testing large structures in an external constraint-free environment to measure the effects of higher order modes and interface stiffness. This test method is applicable to structures with distinct degree-of-freedom interfaces to other system components. A theoretical residual function in the displacement/force domain has the characteristics of a relatively flat line in the lower frequencies and a slight upward curvature in the higher frequency range. In the test residual function, the above-mentioned characteristics can be seen in the data, but due to the present limitations in the modal parameter evaluation (natural frequencies and mode shapes) of test data, the residual function has regions of ragged data. A second order polynomial curve fit is required to obtain the residual flexibility term. A weighting function of the data is generated by examining the variances between neighboring data points. From a weighted second-order polynomial curve fit, an accurate residual flexibility value can be obtained. The residual flexibility value and free-free modes from testing are used to improve a mathematical model of the structure. The residual flexibility modal test method is applied to a straight beam with a trunnion appendage and a space shuttle payload pallet simulator.

  3. The Analysis of the Radio Light Curves of Low-peak Frequency Blazars

    NASA Astrophysics Data System (ADS)

    Wang, H. T.

    2014-03-01

    From a large amount of literatures, we have collected a large number of light curve data of BL Lacertae, 0235+164, OQ 530, 0716+714, 3C 345, and 3C 273 in 4.8 GHz, 8 GHz, 14.5 GHz, 22 GHz, and 37 GHz for more than 30 years. The correlation and time delay have been investigated with the discrete correlation function method. The light curve period and timescale have been analyzed with the structure function method. It is shown from the analytical results that for the fractional variability amplitudes of these six blazars, 0716+714 and 0235+164 have the largest, 3C 345 and OQ 530 come second, and 3C 273 and BL Lacertae have the smallest. The light curve in the high frequency leads that in the low frequency for 0235+164, and conversely for 3C 345. For the other blazars, the above two situations both exist. The results from the structure function method show that the variability timescale, the fitting slope, and the variability period of 3C 345 are larger than those of the other five blazars, respectively. This may indicates that there are different physical processes in 3C 345.

  4. Light Curve Analysis of the Short Period Solar-Type Binary, EK Comae Berenices

    NASA Astrophysics Data System (ADS)

    Samec, Ronald G.; Gray, Jamison D.; Carrigan, Brian

    1995-05-01

    The thirteenth mag variable, EK Comae Berenices, was discovered by Kinman (1966) in a study of the fields near the North Galactic Pole. He identified it as a W UMa variable. This binary was brought to our attention by the AAVSO observer,Borovicka, who conducted a thorough visual investigation. Subsequently, we obtained complete B,V photoelectric light curves of the system phased from observations taken 11, 12 and 14 February and 9, 12 May, 1994 at Lowell Observatory, Flagstaff, Arizona. The 0.78-m National Undergraduate Research Observatory reflector was used with a thermoelectrically cooled PMT. Five epochs of minimicrons light were determined from observations made during two secondary and three primary eclipses. The bisection-of-chords technique was utilized in their determination. Improved linear and quadratic ephemerides were calculated from all available epochs of minima. The quadratic term of the second ephemeris is marginally significant and negative. Because of its small magnitude and doubtful significance, we cannot regard it as proof that the orbital evolution of EK Com is now dominated by magnetic breaking. The B, V simultaneous light curve solution yields an extreme mass ratio of 3.3 and a fill-out of 10%. We also modeled a 12 degree super-luminous region on the cooler component, simultaneously adjusting its parameters in the WD differential corrections procedure along with the other light curve parameters.

  5. AN ANALYSIS OF THE SHAPES OF INTERSTELLAR EXTINCTION CURVES. VI. THE NEAR-IR EXTINCTION LAW

    SciTech Connect

    Fitzpatrick, E. L.; Massa, D. E-mail: massa@derckmassa.net

    2009-07-10

    We combine new observations from the Hubble Space Telescope's Advanced Camera of Survey with existing data to investigate the wavelength dependence of near-IR (NIR) extinction. Previous studies suggest a power law form for NIR extinction, with a 'universal' value of the exponent, although some recent observations indicate that significant sight line-to-sight line variability may exist. We show that a power-law model for the NIR extinction provides an excellent fit to most extinction curves, but that the value of the power, {beta}, varies significantly from sight line to sight line. Therefore, it seems that a 'universal NIR extinction law' is not possible. Instead, we find that as {beta} decreases, R(V) {identical_to} A(V)/E(B - V) tends to increase, suggesting that NIR extinction curves which have been considered 'peculiar' may, in fact, be typical for different R(V) values. We show that the power-law parameters can depend on the wavelength interval used to derive them, with the {beta} increasing as longer wavelengths are included. This result implies that extrapolating power-law fits to determine R(V) is unreliable. To avoid this problem, we adopt a different functional form for NIR extinction. This new form mimics a power law whose exponent increases with wavelength, has only two free parameters, can fit all of our curves over a longer wavelength baseline and to higher precision, and produces R(V) values which are consistent with independent estimates and commonly used methods for estimating R(V). Furthermore, unlike the power-law model, it gives R(V)s that are independent of the wavelength interval used to derive them. It also suggests that the relation R(V) = -1.36 E(K-V)/(E(B-V)) - 0.79 can estimate R(V) to {+-}0.12. Finally, we use model extinction curves to show that our extinction curves are in accord with theoretical expectations, and demonstrate how large samples of observational quantities can provide useful constraints on the grain properties.

  6. Advances in the interpretation and analysis of lunar occultation light curves

    NASA Astrophysics Data System (ADS)

    Richichi, A.; Glindemann, A.

    2012-02-01

    Context. The introduction of fast 2D detectors and the use of very large telescopes have significantly advanced the sensitivity and accuracy of the lunar occultation technique. Recent routine observations at the ESO Very Large Telescope have yielded hundreds of events with results, especially in the area of binary stars, which are often beyond the capabilities of any other techniques. Aims: With the increase in the quality and in the number of the events, subtle features in the light curve patterns have occasionally been detected which challenge the standard analytical definition of the lunar occultation phenomenon as diffraction from an infinite straight edge. We investigate the possible causes for the observed peculiarities. Methods: We have evaluated the available statistics of distortions in occultation light curves observed at the ESO VLT, and compared it to data from other facilities. We have developed an alternative approach to model and interpret lunar occultation light curves, based on 2D diffraction integrals describing the light curves in the presence of an arbitrary lunar limb profile. We distinguish between large limb irregularities requiring the Fresnel diffraction formalism, and small irregularities described by Fraunhofer diffraction. We have used this to generate light curves representative of several limb geometries, and attempted to relate them to some of the peculiar data observed. Results: We conclude that the majority of the observed peculiarities is due to limb irregularities, which can give origin both to anomalies in the amplitude of the diffraction fringes and to varying limb slopes. We investigate also other possible effects, such as detector response and atmospheric perturbations, finding them negligible. We have developed methods and procedures that for the first time allow us to analyze data affected by limb irregularities, with large ones bending the fringe pattern along the shape of the irregularity, and small ones creating fringe amplitude perturbations in comparison to the ideal fringe pattern. Conclusions: The effects of a variable limb slope can be satisfactorily corrected. More complex limb irregularities could be fitted in principle with a grid search based on the standard analytical model, however this method is time consuming and does not lead to unique solutions. The incidence of the limb perturbations is relatively small, but its significance is increased with the use of very large telescopes due both to the footprint at the lunar limb and to the increased sensitivity. In general, we recommend to observe occultations using sub-pupils. This will be a necessary requirement with the next generation of extremely large telescopes. Based on observations made with ESO telescopes at Paranal Observatory.

  7. Magnetic unmixing of first-order reversal curve diagrams using principal component analysis

    NASA Astrophysics Data System (ADS)

    Lascu, Ioan; Harrison, Richard; Li, Yuting; Piotrowski, Alexander; Channell, James; Muraszko, Joy; Hodell, David

    2015-04-01

    We have developed a magnetic unmixing method based on principal component analysis (PCA) of entire first-order reversal curve (FORC) diagrams. FORC diagrams are an advanced hysteresis technique that allows the quantitative characterisation of magnetic grain size, domain state, coercivity and spatial distribution of ensembles of particles within a sample. PCA has been previously applied on extracted central ridges from FORC diagrams of sediment samples containing single domain (SD) magnetite produced by magnetotactic bacteria (Heslop et al., 2014). We extend this methodology to the entire FORC space, which incorporates additional SD signatures, pseudo-single domain (PSD) and multi domain (MD) magnetite signatures, as well as fingerprints of other minerals, such as hematite (HEM). We apply the PCA by resampling the FORC distribution on a regular grid designed to encompass all significant features. Typically 80-90% of the variability within the FORC dataset is described by one or two principal components. Individual FORCs are recast as linear combinations of physically distinct end-member FORCs defined using the principal components and constraints derived from physical modelling. In a first case study we quantify the spatial variation of end-member components in surficial sediments along the North Atlantic Deep Water (NADW) from Iceland to Newfoundland. The samples have been physically separated into granulometric fractions, which added a further constraint in determining three end members used to model the magnetic ensemble, namely a coarse silt-sized MD component, a fine silt-sized PSD component, and a mixed clay-sized component containing both SD magnetite and hematite (SD+HEM). Sediments from core tops proximal to Iceland are dominated by the SD+HEM component, whereas those closer to Greenland and Canada are increasingly dominated by MD grains. Iceland sediments follow a PSD to SD+HEM trend with increasing grain-size fraction, whereas the Greenland and North America sediments follow a distinct PSD to MD trend. The PCA suggests that fine Icelandic sediments are being transported by NADW flow westward. The presence of the SD+HEM component in all size fractions of the Iceland sediment implies that this fine-grained component is not physically separable from the coarser detrital grains. This is consistent with hematite-coated sediment grains derived from European red sandstones being advected to Iceland. In a second case study we investigate temporal variations of end-member components in binary mixtures from North Atlantic sediment cores collected from the Rockall Basin and the Iberian Margin. Both these locations are characterised by sediments containing magnetosomes and fine detrital PSD grains. For the Rockall Basin samples PCA unmixing was compared to the central ridge extraction quantification method (Egli et al., 2010), yielding quantitatively similar results, whereby the detrital input decreases with time from the Last Glacial Maximum to the Holocene, superimposed on a relatively constant bacterial input. Recent Iberian Margin sediments offer insight into fine-scale variations of detrital PSD and interacting magnetosomes along a redox gradient.

  8. The Vanderbilt EB Factory: Development of Light Curve Analysis Tools for Precision Stellar Astrophysics with Kepler Eclipsing Binaries

    NASA Astrophysics Data System (ADS)

    Stassun, Keivan; Paegert, M.; De Lee, N. M.; Cargile, P.

    2013-01-01

    The goal of the Vanderbilt EB Factory is to develop an end-to-end computational pipeline that allows automatic processing of massive amounts of light curve data -- from period finding, to object classification, to determination of the stellar physical properties -- in order to find the most scientifically interesting eclipsing binaries (EBs) and to permit accurate modeling of these EBs for detailed tests and benchmarking of theoretical stellar evolution models. We are integrating the most successful algorithms into a single, cohesive workflow environment, and are applying this 'EB Factory' to the full public Kepler dataset to find and characterize new "benchmark grade" EBs, and will disseminate both the enhanced data products from this pipeline and the pipeline itself to the broader NASA science community, especially other Kepler mission researchers. More generally, we are developing the EB Factory as a flexible, open source, modular framework in order to permit simple modifications by other users for a wide array of other types of variable stars of interest, such as RR Lyraes. Finally, we will present our developing suite of light-curve analysis tools available to the community from the Vanderbilt Initiative in Data-intensive Astrophysics (VIDA), including the Filtergraph instant data portal service, and the web-based LCchopper and LCanimator light-curve analysis services.

  9. Barcoding Melting Curve Analysis for Rapid, Sensitive, and Discriminating Authentication of Saffron (Crocus sativus L.) from Its Adulterants

    PubMed Central

    Cao, Liang; Yuan, Yuan; Chen, Min; Jin, Yan; Huang, Luqi

    2014-01-01

    Saffron (Crocus sativus L.) is one of the most important and expensive medicinal spice products in the world. Because of its high market value and premium price, saffron is often adulterated through the incorporation of other materials, such as Carthamus tinctorius L. and Calendula officinalis L. flowers, Hemerocallis L. petals, Daucus carota L. fleshy root, Curcuma longa L. rhizomes, Zea may L., and Nelumbo nucifera Gaertn. stigmas. To develop a straightforward, nonsequencing method for rapid, sensitive, and discriminating detection of these adulterants in traded saffron, we report here the application of a barcoding melting curve analysis method (Bar-MCA) that uses the universal chloroplast plant DNA barcoding region trnH-psbA to identify adulterants. When amplified at DNA concentrations and annealing temperatures optimized for the curve analysis, peaks were formed at specific locations for saffron (81.92°C) and the adulterants: D. carota (81.60°C), C. tinctorius (80.10°C), C. officinalis (79.92°C), Dendranthema morifolium (Ramat.) Tzvel. (79.62°C), N. nucifera (80.58°C), Hemerocallis fulva (L.) L. (84.78°C), and Z. mays (84.33°C). The constructed melting curves for saffron and its adulterants have significantly different peak locations or shapes. In conclusion, Bar-MCA could be a faster and more cost-effective method to authenticate saffron and detect its adulterants. PMID:25548775

  10. Barcoding melting curve analysis for rapid, sensitive, and discriminating authentication of saffron (Crocus sativus L.) from its adulterants.

    PubMed

    Jiang, Chao; Cao, Liang; Yuan, Yuan; Chen, Min; Jin, Yan; Huang, Luqi

    2014-01-01

    Saffron (Crocus sativus L.) is one of the most important and expensive medicinal spice products in the world. Because of its high market value and premium price, saffron is often adulterated through the incorporation of other materials, such as Carthamus tinctorius L. and Calendula officinalis L. flowers, Hemerocallis L. petals, Daucus carota L. fleshy root, Curcuma longa L. rhizomes, Zea may L., and Nelumbo nucifera Gaertn. stigmas. To develop a straightforward, nonsequencing method for rapid, sensitive, and discriminating detection of these adulterants in traded saffron, we report here the application of a barcoding melting curve analysis method (Bar-MCA) that uses the universal chloroplast plant DNA barcoding region trnH-psbA to identify adulterants. When amplified at DNA concentrations and annealing temperatures optimized for the curve analysis, peaks were formed at specific locations for saffron (81.92°C) and the adulterants: D. carota (81.60°C), C. tinctorius (80.10°C), C. officinalis (79.92°C), Dendranthema morifolium (Ramat.) Tzvel. (79.62°C), N. nucifera (80.58°C), Hemerocallis fulva (L.) L. (84.78°C), and Z. mays (84.33°C). The constructed melting curves for saffron and its adulterants have significantly different peak locations or shapes. In conclusion, Bar-MCA could be a faster and more cost-effective method to authenticate saffron and detect its adulterants. PMID:25548775

  11. Tests of a Simulated Annealing Program for Eclipsing Binary Light Curve Analysis

    NASA Astrophysics Data System (ADS)

    Milone, Eugene F.; Kallrath, J.

    2007-05-01

    Numerical experiments have been carried out with a Simulated Annealing program incorporated into the light curve modeling package WD2007, the latest version of this package initially called WD95, developed and maintained by JK. Simulated annealing (SA) is one a number of metaheuristic methods that have been used in various scientific, economic, and business applications, to seek the absolute minimum of functions in multi-dimensional parameter space. SA draws on an analogue from metallurgy that makes use of an optimum cooling process. The search is conducted, as with other optimization procedures, by following a course toward the deepest minimum, but permits jumps to less optimum solutions by a quasi-random procedure using the "Metropolis criterion," involving a probability that decreases with the 'temperature," a quantity that describes the annealing state over time. It is this capability of escaping from a local minimum that allows wider sampling of parameter solution space. We used as test data a simulated light-curve, based loosely on light curves of the over-contact system V781 Tau. In this work we tested the goodness of fit and the efficiency of the SA algorithm we employed, against our damped least squares and simplex programs, also located in WD2007. Although we find that SA as coded here, is far less efficient than DLS (a purely-down-hill gradient program) and simplex, it appears sufficiently robust to avoid getting stuck in a local minimum, for the most part, if the initial "temperature" is high enough. It is, however, hardly fool-proof. Nevertheless, for initial model exploration, and as a check on solutions found by the other methods, simulated annealing appears to offer another useful test in the search for true global minima. This work was supported in part by grants to EFM from the Canadian Natural Sciences and Engineering Research Council.

  12. Estimate of soil hydraulic properties from disc infiltrometer three-dimensional infiltration curve. Numerical analysis and field application

    NASA Astrophysics Data System (ADS)

    Latorre, B.; Peña, C.; Lassabatere, L.; Angulo-Jaramillo, R.; Moret-Fernández, D.

    2015-08-01

    Based on the analysis of Haverkamp et al. (1994), this paper presents a new technique to estimate the soil hydraulic properties (sorptivity, S, and hydraulic conductivity, K) from the full-time cumulative infiltration curves. The proposed method, which will be named as the Numerical Solution of the Haverkamp equation (NSH), was validated on 12 synthetic soils simulated with HYDRUS-3D. The K values used to simulate the synthetic curves were compared to those estimated with the NSH method. A procedure to detect and remove the effect of the contact sand layer on the cumulative infiltration curve was also developed. A sensitivity analysis was performed using the water level measurement as uncertainty source and the procedure was evaluated considering different infiltration times and data noise (e.g. air-bubbling in the infiltrometer). The good correlation between the K used in HYDRUS-3D to model the infiltration curves and those obtained by the NSH method (R2 = 0.98) indicates this technique is robust enough to estimate the soil hydraulic conductivity from complete infiltration curves. The numerical procedure to detect and remove the influence of the contact sand layer on the K and S estimates resulted to be robust and efficient. A negative effect of the curve infiltration noise on the K estimate was observed. The results showed that infiltration time was an important factor to estimate K. Smaller values of K or lower uncertainty required longer infiltration times. In a second step, the technique was tested in field conditions on 266 different soils at saturation conditions, using a 10 cm diameter disc infiltrometer. The NSH method was compared to the standard differentiated linearization procedure (DL), which estimates the hydraulic parameters using the simplified Haverkamp et al. (1994) equation, valid only for short to medium times. Compared to DL, NSH was considerably less affected by the infiltration bubbling and the contact sand layer, and allowed more robust estimates of K and S. Although comparable S values were obtained with both methods, the NSH technique, which is not limited to short times, resulted in more accurate and robust estimates for K. This paper demonstrates the NSH method is a significant advance to estimate of the soil hydraulic properties from the transient water flow.

  13. Analysis and solution of the light and radial velocity curves of the contact binary TY Bootis

    SciTech Connect

    Milone, E.F.; Groisman, G.; Fry, D.J.I.; Bradstreet, D.H. Eastern College, Saint Davids, PA )

    1991-04-01

    Observations and analyses of the binary TY Bootis are presented. Radial velocity data are used for the first time to establish the mass ratio without ambiguity, and an advanced version of the Wilson-Devinney synthetic light curve program is used to analyze and solve the system. A reasonably robust set of parameters is obtained. TY Boo is found to be a W-type W UMa system with a mass ratio near two and a contact parameter of 0.12 + or - 0.903, indicating only shallow contact. 69 refs.

  14. Buckling Analysis of Anisotropic Curved Panels and Shells with Variable Curvature

    NASA Technical Reports Server (NTRS)

    Jaunky, Navin; Knight, Norman F., Jr.; Ambur, Damodar R.

    1998-01-01

    A buckling formulation for anisotropic curved panels with variable curvature is presented in this paper. The variable curvature panel is assumed to consists of two or more panels of constant but different curvatures. Bezier functions are used as Ritz functions Displacement (C(sup 0)), and slope (C(sup 1)) continuities between segments are imposed by manipulation of the Bezier control points. A first-order shear-deformation theory is used in the buckling formulation. Results obtained from the present formulation are compared with those from finite element simulations and are found to be in good agreement.

  15. Dose–response curve slope is a missing dimension in the analysis of HIV-1 drug resistance

    PubMed Central

    Sampah, Maame Efua S.; Shen, Lin; Jilek, Benjamin L.; Siliciano, Robert F.

    2011-01-01

    HIV-1 drug resistance is a major clinical problem. Resistance is evaluated using in vitro assays measuring the fold change in IC50 caused by resistance mutations. Antiretroviral drugs are used at concentrations above IC50, however, and inhibition at clinical concentrations can only be predicted from IC50 if the shape of the dose–response curve is also known. Curve shape is influenced by cooperative interactions and is described mathematically by the slope parameter or Hill coefficient (m). Implicit in current analysis of resistance is the assumption that mutations shift dose–response curves to the right without affecting the slope. We show here that m is altered by resistance mutations. For reverse transcriptase and fusion inhibitors, single resistance mutations affect both slope and IC50. For protease inhibitors, single mutations primarily affect slope. For integrase inhibitors, only IC50 is affected. Thus, there are fundamental pharmacodynamic differences in resistance to different drug classes. Instantaneous inhibitory potential (IIP), the log inhibition of single-round infectivity at clinical concentrations, takes into account both slope and IC50, and thus provides a direct measure of the reduction in susceptibility produced by mutations and the residual activity of drugs against resistant viruses. The standard measure, fold change in IC50, does not correlate well with changes in IIP when mutations alter slope. These results challenge a fundamental assumption underlying current analysis of HIV-1 drug resistance and suggest that a more complete understanding of how resistance mutations reduce antiviral activity requires consideration of a previously ignored parameter, the dose–response curve slope. PMID:21502494

  16. Dose-response curve slope is a missing dimension in the analysis of HIV-1 drug resistance.

    PubMed

    Sampah, Maame Efua S; Shen, Lin; Jilek, Benjamin L; Siliciano, Robert F

    2011-05-01

    HIV-1 drug resistance is a major clinical problem. Resistance is evaluated using in vitro assays measuring the fold change in IC(50) caused by resistance mutations. Antiretroviral drugs are used at concentrations above IC(50), however, and inhibition at clinical concentrations can only be predicted from IC(50) if the shape of the dose-response curve is also known. Curve shape is influenced by cooperative interactions and is described mathematically by the slope parameter or Hill coefficient (m). Implicit in current analysis of resistance is the assumption that mutations shift dose-response curves to the right without affecting the slope. We show here that m is altered by resistance mutations. For reverse transcriptase and fusion inhibitors, single resistance mutations affect both slope and IC(50). For protease inhibitors, single mutations primarily affect slope. For integrase inhibitors, only IC(50) is affected. Thus, there are fundamental pharmacodynamic differences in resistance to different drug classes. Instantaneous inhibitory potential (IIP), the log inhibition of single-round infectivity at clinical concentrations, takes into account both slope and IC(50), and thus provides a direct measure of the reduction in susceptibility produced by mutations and the residual activity of drugs against resistant viruses. The standard measure, fold change in IC(50), does not correlate well with changes in IIP when mutations alter slope. These results challenge a fundamental assumption underlying current analysis of HIV-1 drug resistance and suggest that a more complete understanding of how resistance mutations reduce antiviral activity requires consideration of a previously ignored parameter, the dose-response curve slope. PMID:21502494

  17. Mode of physical activity and self-efficacy in older adults: a latent growth curve analysis.

    PubMed

    McAuley, E; Katula, J; Mihalko, S L; Blissmer, B; Duncan, T E; Pena, M; Dunn, E

    1999-09-01

    A randomized controlled trial examined the effect of two physical activity modes on changes in self-efficacy over the course of a 12-month period in older, formerly sedentary adults (N = 174, M age = 65.5 years). Participants were randomized into either an aerobic activity group or a stretching and toning group. Structural equation modeling was employed to conduct multiple sample latent growth curve analyses of individual growth in exercise and physical self-efficacy over time. Results revealed a curvilinear growth pattern for both types of efficacy with increases occurring over the first 6 months followed by declines at the 6-month follow-up. There was a significant treatment by mean level growth interaction for exercise efficacy with both groups increasing over time, but the aerobic group evidenced a twofold increase in growth over the stretching group. Structural analyses indicated that frequency of exercise participation was a significant predictor of overall growth in efficacy, and improvements in fitness were only related to exercise efficacy growth in the stretching group. Findings are discussed in terms of social cognitive theory and further application of latent growth curve modeling to studies of physical activity effects in older adults. PMID:10542821

  18. The Application of the Principal Curve Analysis Technique to Smooth Beam Lines

    SciTech Connect

    Friedsam, H.; Oren, W.; /SLAC

    2005-08-12

    The smoothness of a beam line refers to the quality of the relative positioning of a number of adjacent beam guiding components. The fact that smoothness is of highest priority when positioning magnets can be seen in the local tolerances imposed by the beam optics. In the past, smoothing has been done by separating horizontal and vertical misalignments and then applying some sort of analytical or manual ''feathering'' technique. The Stanford Linear Collider (SLC) did not easily lend itself to this sort of smoothing because of the highly coupled nature of its pitched and rolled beam line. This paper will discuss an attempt to develop a repeatable method which is independent of the inconsistencies of human judgment and can simultaneously smooth in two or more dimensions. Four major goals were defined for the smoothing algorithm used on the SLC alignment. The first, was to simultaneously model errors for both horizontal and vertical directions. Secondly, a smooth curve whose shape was suggested by the data and not by a predetermined model was implied by the fact that unknown systematic errors were being eliminated. Thirdly, this curve must be a reproducibly fit, independent of the inconsistent nature of human judgment. Fourth, the result of the procedure was to minimize the number and size of magnet movements to reach the final alignment criteria.

  19. An empirical study of sample size in ROC-curve analysis of fingerprint data

    NASA Astrophysics Data System (ADS)

    Wu, Jin Chu; Wilson, Charles L.

    2006-04-01

    The fingerprint datasets in many cases may exceed millions of samples. Thus, the needed size of a biometric evaluation test sample is an important issue in terms of both efficiency and accuracy. In this article, an empirical study, namely, using Chebyshev's inequality in combination with simple random sampling, is applied to determine the sample size for biometric applications. No parametric model is assumed, since the underlying distribution functions of the similarity scores are unknown. The performance of fingerprint-image matcher is measured by a Receiver Operating Characteristic (ROC) curve. Both the area under an ROC curve and the True Accept Rate (TAR) at an operational False Accept Rate (FAR) are employed. The Chebyshev's greater-than-95% intervals of using these two criteria based on 500 Monte Carlo iterations are computed for different sample sizes as well as for both high- and low-quality fingerprint-image matchers. The stability of such Monte Carlo calculations with respect to the number of iterations is also explored. The choice of sample size depends on matchers' qualities as well as on which performance criterion is invoked. In general, for 6,000 match similarity scores, 50,000 to 70,000 scores randomly selected from 35,994,000 non-match similarity scores can ensure the accuracy with greater-than-95% probability.

  20. Measuring recession severity and its impact on healthcare expenditure.

    PubMed

    Keegan, Conor; Thomas, Steve; Normand, Charles; Portela, Conceição

    2013-06-01

    The financial crisis that manifested itself in late 2007 resulted in a Europe-wide economic crisis by 2009. As the economic climate worsened, Governments and households were put under increased strain and more focus was placed on prioritising expenditures. Across European countries and their heterogeneous health care systems, this paper examines the initial responsiveness of health expenditures to the crisis and whether recession severity can be considered a predictor of health expenditure growth. In measuring severity we move away from solely gross domestic product (GDP) as a metric and construct a recession severity index predicated on a number of key macroeconomic indicators. We then regress this index on measures of total, public and private health expenditure to identify potential relationships. Analysis suggests that for 2009, the Baltic States, along with Ireland, Italy and Greece, experienced comparatively severe recessions. We find, overall, an initial counter-cyclical response in health spending (both public and private) across countries. However, our analysis finds evidence of a negative relationship between recession severity and changes in certain health expenditures. As a predictor of health expenditure growth in 2009, the derived index is an improvement over GDP change alone. PMID:23417124

  1. Strategies for Supporting Recess in Elementary Schools

    ERIC Educational Resources Information Center

    Centers for Disease Control and Prevention, 2014

    2014-01-01

    Recess provides students with a needed break from their structured school day. It can improve children's physical, social, and emotional well-being, and enhance learning. Recess helps children meet the goal of 60 minutes of physical activity (PA) each day, as recommended by the US Department of Health and Human Services. National…

  2. The Crucial Role of Recess in Schools

    ERIC Educational Resources Information Center

    Ramstetter, Catherine L.; Murray, Robert; Garner, Andrew S.

    2010-01-01

    Background: Recess is at the heart of a vigorous debate over the role of schools in promoting optimal child development and well-being. Reallocating time to accentuate academic concerns is a growing trend and has put recess at risk. Conversely, pressure to increase activity in school has come from efforts to combat childhood obesity. The purpose…

  3. Recess for Elementary School Students. Position Statement

    ERIC Educational Resources Information Center

    National Association for Sport and Physical Education, 2006

    2006-01-01

    It is the position of the National Association for Sport and Physical Education (NASPE) that all elementary school children should be provided with at least one daily period of recess of at least 20 minutes in length. Recess is an essential component of a comprehensive school physical activity program and of the total education experience for…

  4. Evolution of the North Caucasus foredeep: constraints based on the analysis of subsidence curves

    NASA Astrophysics Data System (ADS)

    Mikhailov, Valentine O.; V. Panina, Ludmila; Polino, Riccardo; Koronovsky, Nikolay V.; Kiseleva, Elena A.; Klavdieva, Natalya V.; Smolyaninova, Ekaterina I.

    1999-06-01

    Using a database of more than 130 wells the Alpine evolution of the North Caucasus foredeep can be described in three main periods. (1) The Early Jurassic to Middle-Late Cretaceous (including the Cenomanian) relates to the initial rifting phase and was characterised by succession of comparatively high rates of subsidence and uplift. During this stage, many events in the eastern and western parts were synchronous, whereas some of them appeared to be smoothed in the Stavropol high. The southern border of the area had a more complex behaviour often moving in the opposite direction relative to the rest of the area. The main peculiarities of evolution of the Great Caucasus region can be explained if we adopt the hypothesis of Stamply and Pillevuit (1993)and suppose that the Early Jurassic extension of the trough was accompanied by a strong left-lateral transform movement. As a result the central part of the Great Caucasus trough formed as a pull-apart basin. Analysis of the style of movements of the southern border of the Scythian plate as well as data on tectonics and volcanism in the Great and Lesser Caucasus showed that other regional compressional and extensional Mesozoic events could also have a transform component. Shear stresses within the lithosphere of the Great Caucasus can be due to oblique subduction or even transform movements at the plate boundary to the south of the Caucasus region ( Dercourt et al., 1993). (2) The period from the Late Cretaceous to the Middle Eocene (from the Turonian to the Bartonian) relates to the oceanic suture of the Lesser Caucasus and was characterised in the Great Caucasus area by alternating subsidence and uplift events of considerably lower amplitude (at least up to the Maastrichtian). Beginning in the Late Paleocene, subsidence curves for almost all the area reflect the same events, but in the western part and also in the north of the central part the rate of movements was considerably higher and since the Late Paleocene short term events in this area took place on the background of rather fast subsidence at nearly constant rate. We believe that this subsidence and formation of the East Black Sea depression have the same origin. We consider strong differences in evolution of the eastern, western and central parts during the second stage to be due to closure of the Lesser Caucasus oceanic basin and arrival of the Nakhichevan block. This led to changes of configuration of the plate boundary and resulted in reorganisation of stress and displacements within the Caucasus region. This reorganisation was a reason for the opening of the East Black Sea depression and rapid subsidence of the western and central parts of the area at the end of the second stage. (3) The period from the Middle Eocene to the present relates to the development of a foreland basin coeval with shortening and uplift in the adjacent Great Caucasus range. It was characterised by alternation of relatively short uplift and longer subsidence events. An important feature of this stage is that although the amplitude of movements varied from place to place, these events were synchronous in all parts of the foredeep (at the Stavropol region sediments preserved only for the beginning of this stage). Formation and evolution of the foredeep during the third stage can not be explained exclusively by elastic flexure. To do this we used the model of a small-scale convection within the asthenosphere ( Mikhailov et al. 1996, 1999). By the comparison of numerical results with the data on the evolution of the North Caucasus foredeep we concluded that there were four main stages of compression in the processes of formation of the Great Caucasus mountain belt. The first compression took place before the Maykopian (between 39.5 and 36.0 Ma). The other three were in the Tarkhanian (16.6-15.8 Ma), Konkian-Early Sarmatian (14.3-12.3 Ma) and Pontian (7.0-5.2 Ma). The different width of the Great Caucasus trough by the beginning of the compression, as well as variations in thickness of the lithosphere and a different thermal state can cause interruption of the formation of the foredeep at the Stavropol high.

  5. Comparison of surface plasmon resonance binding curves for characterization of protein interactions and analysis of screening data.

    PubMed

    Karlsson, Robert; Pol, Ewa; Frostell, Åsa

    2016-06-01

    Label-free technologies, such as surface plasmon resonance, are typically used for characterization of protein interactions and in screening for selection of antibodies or small molecules with preferred binding properties. In characterization, complete binding curves are normally fitted to defined interaction models to provide affinity and rate constants, whereas report points indicative of binding and stability of binding are often used for analysis of screening data. As an alternative to these procedures, here we describe how the analysis, in certain cases, can be simplified by comparison with upper and lower limit binding curves that represent expected or wanted binding profiles. The use of such profiles is applied to the analysis of kinetically complex IgG-Fc receptor interactions and for selection of antibody candidates. The comparison procedure described may be particularly useful in batch-to-batch comparisons and in comparability and biosimilar studies of biotherapeutic medicines. In screening, more informed selections may become possible as entire binding profiles and not a few report points are used in the analysis and as each new sample is directly compared with a predefined outcome. PMID:27019155

  6. A unified approach for nonlinear vibration analysis of curved structures using non-uniform rational B-spline representation

    NASA Astrophysics Data System (ADS)

    Askari, H.; Esmailzadeh, E.; Barari, A.

    2015-09-01

    A novel procedure for the nonlinear vibration analysis of curved beam is presented. The Non-Uniform Rational B-Spline (NURBS) is combined with the Euler-Bernoulli beam theory to define the curvature of the structure. The governing equation of motion and the general frequency formula, using the NURBS variables, is applicable for any type of curvatures, is developed. The Galerkin procedure is implemented to obtain the nonlinear ordinary differential equation of curved system and the multiple time scales method is utilized to find the corresponding frequency responses. As a case study, the nonlinear vibration of carbon nanotubes with different shapes of curvature is investigated. The effect of oscillation amplitude and the waviness on the natural frequency of the curved nanotube is evaluated and the primary resonance case of system with respect to the variations of different parameters is discussed. For the sake of comparison of the results obtained with those from the molecular dynamic simulation, the natural frequencies evaluated from the proposed approach are compared with those reported in literature for few types of carbon nanotube simulation.

  7. Progress curve analysis for enzyme and microbial kinetic reactions using explicit solutions based on the Lambert W function.

    PubMed

    Goudar, Chetan T; Harris, Steve K; McInerney, Michael J; Suflita, Joseph M

    2004-12-01

    We present a simple method for estimating kinetic parameters from progress curve analysis of biologically catalyzed reactions that reduce to forms analogous to the Michaelis-Menten equation. Specifically, the Lambert W function is used to obtain explicit, closed-form solutions to differential rate expressions that describe the dynamics of substrate depletion. The explicit nature of the new solutions greatly simplifies nonlinear estimation of the kinetic parameters since numerical techniques such as the Runge-Kutta and Newton-Raphson methods used to solve the differential and integral forms of the kinetic equations, respectively, are replaced with a simple algebraic expression. The applicability of this approach for estimating Vmax and Km in the Michaelis-Menten equation was verified using a combination of simulated and experimental progress curve data. For simulated data, final estimates of Vmax and Km were close to the actual values of 1 microM/h and 1 microM, respectively, while the standard errors for these parameter estimates were proportional to the error level in the simulated data sets. The method was also applied to hydrogen depletion experiments by mixed cultures of bacteria in activated sludge resulting in Vmax and Km estimates of 6.531 microM/h and 2.136 microM, respectively. The algebraic nature of this solution, coupled with its relatively high accuracy, makes it an attractive candidate for kinetic parameter estimation from progress curve data. PMID:15488275

  8. Type curve analysis of inertial effects in the response of a well to a slug test.

    USGS Publications Warehouse

    Kipp, K.L., Jr.

    1985-01-01

    The water level response to a slug or bailer test in a well completed in a confined aquifer, has been evaluated taking into account well-bore storage and inertial effects of the water column in the well. The response range, from overdamped with negligible inertial effects to damped oscillations, was covered employing numerical inversions of the Laplace-transform solution. By scaling the time with respect to the undamped natural period of the well-aquifer system and by using the damping parameter for a second-order damped, inertial-elastic system, a set of type curves was constructed that enables water level response data from a slug or bailer test to be analyzed under conditions where the inertial parameter is large.-from Author

  9. Modal analysis using a Fourier analyzer, curve-fitting, and modal tuning

    NASA Technical Reports Server (NTRS)

    Craig, R. R., Jr.; Chung, Y. T.

    1981-01-01

    The proposed modal test program differs from single-input methods in that preliminary data may be acquired using multiple inputs, and modal tuning procedures may be employed to define closely spaced frquency modes more accurately or to make use of frequency response functions (FRF's) which are based on several input locations. In some respects the proposed modal test proram resembles earlier sine-sweep and sine-dwell testing in that broadband FRF's are acquired using several input locations, and tuning is employed to refine the modal parameter estimates. The major tasks performed in the proposed modal test program are outlined. Data acquisition and FFT processing, curve fitting, and modal tuning phases are described and examples are given to illustrate and evaluate them.

  10. Predictors of physical activity patterns across adulthood: a growth curve analysis.

    PubMed

    Kern, Margaret L; Reynolds, Chandra A; Friedman, Howard S

    2010-08-01

    Activity level is a core but understudied individual difference. Understanding patterns of physical activity over long periods may be key to understanding why some individuals develop healthy lifestyles. The present study transformed qualitative information from the Terman Life Cycle Study to examine patterns of leisure time physical activity across four decades (1936-1972). Activities were converted into metabolic equivalent (MET) ratings, and then activity patterns, individual variation, and child and adult personality predictors of differing trajectories were examined using growth curve modeling. For overall activity, a quadratic model fit best, with decelerating decline as people aged. Males were consistently more active than females. Much individual variation was present, but childhood energy and sociability, and adult extraversion and neuroticism predicted average activity levels and change. Results suggest that physical activity needs to be understood within the context of the individual's personality and long-term trajectory, not merely current motivations. PMID:20573949

  11. Single Cell Wall Nonlinear Mechanics Revealed by a Multiscale Analysis of AFM Force-Indentation Curves.

    PubMed

    Digiuni, Simona; Berne-Dedieu, Annik; Martinez-Torres, Cristina; Szecsi, Judit; Bendahmane, Mohammed; Arneodo, Alain; Argoul, Françoise

    2015-05-01

    Individual plant cells are rather complex mechanical objects. Despite the fact that their wall mechanical strength may be weakened by comparison with their original tissue template, they nevertheless retain some generic properties of the mother tissue, namely the viscoelasticity and the shape of their walls, which are driven by their internal hydrostatic turgor pressure. This viscoelastic behavior, which affects the power-law response of these cells when indented by an atomic force cantilever with a pyramidal tip, is also very sensitive to the culture media. To our knowledge, we develop here an original analyzing method, based on a multiscale decomposition of force-indentation curves, that reveals and quantifies for the first time the nonlinearity of the mechanical response of living single plant cells upon mechanical deformation. Further comparing the nonlinear strain responses of these isolated cells in three different media, we reveal an alteration of their linear bending elastic regime in both hyper- and hypotonic conditions. PMID:25954881

  12. On-chip magnetic bead-based DNA melting curve analysis using a magnetoresistive sensor

    NASA Astrophysics Data System (ADS)

    Rizzi, Giovanni; Østerberg, Frederik W.; Henriksen, Anders D.; Dufva, Martin; Hansen, Mikkel F.

    2015-04-01

    We present real-time measurements of DNA melting curves in a chip-based system that detects the amount of surface-bound magnetic beads using magnetoresistive magnetic field sensors. The sensors detect the difference between the amount of beads bound to the top and bottom sensor branches of the differential sensor geometry. The sensor surfaces are functionalized with wild type (WT) and mutant type (MT) capture probes, differing by a single base insertion (a single nucleotide polymorphism, SNP). Complementary biotinylated targets in suspension couple streptavidin magnetic beads to the sensor surface. The beads are magnetized by the field arising from the bias current passed through the sensors. We demonstrate the first on-chip measurements of the melting of DNA hybrids upon a ramping of the temperature. This overcomes the limitation of using a single washing condition at constant temperature. Moreover, we demonstrate that a single sensor bridge can be used to genotype a SNP.

  13. Classification of breast mass lesions using model-based analysis of the characteristic kinetic curve derived from fuzzy c-means clustering.

    PubMed

    Chang, Yeun-Chung; Huang, Yan-Hao; Huang, Chiun-Sheng; Chang, Pei-Kang; Chen, Jeon-Hor; Chang, Ruey-Feng

    2012-04-01

    The purpose of this study is to evaluate the diagnostic efficacy of the representative characteristic kinetic curve of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) extracted by fuzzy c-means (FCM) clustering for the discrimination of benign and malignant breast tumors using a novel computer-aided diagnosis (CAD) system. About the research data set, DCE-MRIs of 132 solid breast masses with definite histopathologic diagnosis (63 benign and 69 malignant) were used in this study. At first, the tumor region was automatically segmented using the region growing method based on the integrated color map formed by the combination of kinetic and area under curve color map. Then, the FCM clustering was used to identify the time-signal curve with the larger initial enhancement inside the segmented region as the representative kinetic curve, and then the parameters of the Tofts pharmacokinetic model for the representative kinetic curve were compared with conventional curve analysis (maximal enhancement, time to peak, uptake rate and washout rate) for each mass. The results were analyzed with a receiver operating characteristic curve and Student's t test to evaluate the classification performance. Accuracy, sensitivity, specificity, positive predictive value and negative predictive value of the combined model-based parameters of the extracted kinetic curve from FCM clustering were 86.36% (114/132), 85.51% (59/69), 87.30% (55/63), 88.06% (59/67) and 84.62% (55/65), better than those from a conventional curve analysis. The A(Z) value was 0.9154 for Tofts model-based parametric features, better than that for conventional curve analysis (0.8673), for discriminating malignant and benign lesions. In conclusion, model-based analysis of the characteristic kinetic curve of breast mass derived from FCM clustering provides effective lesion classification. This approach has potential in the development of a CAD system for DCE breast MRI. PMID:22245697

  14. Recess Physical Activity and Perceived School Environment among Elementary School Children

    PubMed Central

    Ishii, Kaori; Shibata, Ai; Sato, Mai; Oka, Koichiro

    2014-01-01

    Differences in recess physical activity (PA) according to perceived school environment among elementary school children were examined. Participants were 103 children from two schools in Japan. PA was measured using accelerometry for seven consecutive days. Time spent in sedentary or PA (light, moderate, or vigorous) during their morning recess (25 min) and lunch recess (15 min) was determined. The School Physical Activity Environment Scale (three factors: equipment, facility, and safety) was used to investigate perceived school environment. Environmental factor scores were assigned to low or high groups for each factor by median. An analysis of covariance, with grade as the covariate, was conducted separately by gender to examine differences in PA between two groups. During lunch recess, boys in the high-equipment group spent significantly more time in moderate PA (high: 1.5; low: 0.8 min) whereas girls in this group spent less time in light PA (9.3, 11.0). Boys in the high-facility group spent significantly less time in sedentary (2.3, 3.9) and more time in vigorous PA (2.4, 1.4) during lunch recess, and girls spent more time in moderate (2.1, 1.2) and vigorous PA (1.9, 1.3) during morning recess. Differences were observed in recess PA according to school environment perceptions. The present study may be useful for further intervention studies for the promotion of PA during recess. PMID:25029495

  15. Genotype-phenotype correlations in recessive RYR1-related myopathies

    PubMed Central

    2013-01-01

    Background RYR1 mutations are typically associated with core myopathies and are the most common overall cause of congenital myopathy. Dominant mutations are most often associated with central core disease and malignant hyperthermia, and genotype-phenotype patterns have emerged from the study of these mutations that have contributed to the understanding of disease pathogenesis. The recent availability of genetic testing for the entire RYR1 coding sequence has led to a dramatic expansion in the identification of recessive mutations in core myopathies and other congenital myopathies. To date, no clear patterns have been identified in these recessive mutations, though no systematic examination has yet been performed. Methods In this study, we investigated genotype-phenotype correlations in a large combined cohort of unpublished (n = 14) and previously reported (n = 92) recessive RYR1 cases. Results Overall examination of this cohort revealed nearly 50% of cases to be non-core myopathy related. Our most significant finding was that hypomorphic mutations (mutations expected to diminish RyR1 expression) were enriched in patients with severe clinical phenotypes. We also determined that hypomorphic mutations were more likely to be encountered in non-central core myopathies. With analysis of the location of non-hypomorphic mutations, we found that missense mutations were generally enriched in the MH/CCD hotspots and specifically enriched in the selectivity filter of the channel pore. Conclusions These results support a hypothesis that loss of protein function is a key predictive disease parameter. In addition, they suggest that decreased RyR1 expression may dictate non-core related pathology though, data on protein expression was limited and should be confirmed in a larger cohort. Lastly, the results implicate abnormal ion conductance through the channel pore in the pathogenesis in recessive core myopathies. Overall, our findings represent a comprehensive analysis of genotype-phenotype associations in recessive RYR1-myopathies. PMID:23919265

  16. Simultaneous detection of Fusarium culmorum and F. graminearum in plant material by duplex PCR with melting curve analysis

    PubMed Central

    Brandfass, Christoph; Karlovsky, Petr

    2006-01-01

    Background Fusarium head blight (FHB) is a disease of cereal crops, which has a severe impact on wheat and barley production worldwide. Apart from reducing the yield and impairing grain quality, FHB leads to contamination of grain with toxic secondary metabolites (mycotoxins), which pose a health risk to humans and livestock. The Fusarium species primarily involved in FHB are F. graminearum and F. culmorum. A key prerequisite for a reduction in the incidence of FHB is an understanding of its epidemiology. Results We describe a duplex-PCR-based method for the simultaneous detection of F. culmorum and F. graminearum in plant material. Species-specific PCR products are identified by melting curve analysis performed in a real-time thermocycler in the presence of the fluorescent dye SYBR Green I. In contrast to multiplex real-time PCR assays, the method does not use doubly labeled hybridization probes. Conclusion PCR with product differentiation by melting curve analysis offers a cost-effective means of qualitative analysis for the presence of F. culmorum and F. graminearum in plant material. This method is particularly suitable for epidemiological studies involving a large number of samples. PMID:16430784

  17. Genetics Home Reference: autosomal recessive axonal neuropathy with neuromyotonia

    MedlinePlus

    ... recessive axonal neuropathy with neuromyotonia autosomal recessive axonal neuropathy with neuromyotonia Enable Javascript to view the expand/ ... Open All Close All Description Autosomal recessive axonal neuropathy with neuromyotonia is a disorder that affects the ...

  18. The dose-response curve of the gravitropic reaction: a re-analysis.

    PubMed

    Perbal, Gérald; Jeune, Bernard; Lefranc, Agnès; Carnero-Diaz, Eugénie; Driss-Ecole, Dominique

    2002-03-01

    The dose-response curve of the gravitropic reaction is often used to evaluate the gravisensing of plant organs. It has been proposed (Larsen 1957) that the response (curvature) varies linearly as a function of the logarithm of the dose of gravistimulus. As this model fitted correctly most of the data obtained in the literature, the presentation time (tp, minimal duration of stimulation in the gravitational field to induce a response) or the presentation dose (dp, minimal quantity in g.s of stimulation to induce a response) were estimated by extrapolating down to zero curvature the straight line representing the response as a function of the logarithm of the stimulus. This method was preferred to a direct measurement of dp or tp with minute stimulations, since very slight gravitropic response cannot be distinguished from the background oscillations of the extremity of the organs. In the present review, it is shown that generally the logarithmic model (L) does not fit the experimental data published in the literature as well as the hyperbolic model (H). The H model in its simplest form is related to a response in which a ligand-receptor system is the limiting phase in the cascade of events leading to the response (Weyers et al. 1987). However, it is demonstrated that the differential growth, responsible for the curvature (and the angle of curvature), would vary as a hyperbolic function of the dose of stimulation, even if several steps involving ligand-receptor systems are responsible for the gravitropic curvature. In the H model, there is theoretically no presentation time (or presentation dose) since the curve passes through the origin. The value of the derivative of the H function equals a/b and represents the slope of the cune at the origin. It could be therefore used to estimate gravisensitivity. This provides a measurement of graviresponsiveness for threshold doses of stimulation. These results imply that the presentation time (or presentation dose) derived from the L model cannot be used anymore as an estimate of gravisensitivity. On the contrary, the perception time (minimal duration of a repeated stimulation which induces a response), which is less than 1 s, should be related to the perception of gravity. The consequences of these results on the mode of action and the nature of graviperception are discussed. PMID:12060255

  19. A novel three-dimensional smile analysis based on dynamic evaluation of facial curve contour

    NASA Astrophysics Data System (ADS)

    Lin, Yi; Lin, Han; Lin, Qiuping; Zhang, Jinxin; Zhu, Ping; Lu, Yao; Zhao, Zhi; Lv, Jiahong; Lee, Mln Kyeong; Xu, Yue

    2016-02-01

    The influence of three-dimensional facial contour and dynamic evaluation decoding on factors of smile esthetics is essential for facial beauty improvement. However, the kinematic features of the facial smile contour and the contribution from the soft tissue and underlying skeleton are uncharted. Here, the cheekbone-maxilla contour and nasolabial fold were combined into a “smile contour” delineating the overall facial topography emerges prominently in smiling. We screened out the stable and unstable points on the smile contour using facial motion capture and curve fitting, before analyzing the correlation between soft tissue coordinates and hard tissue counterparts of the screened points. Our finding suggests that the mouth corner region was the most mobile area characterizing smile expression, while the other areas remained relatively stable. Therefore, the perioral area should be evaluated dynamically while the static assessment outcome of other parts of the smile contour contribute partially to their dynamic esthetics. Moreover, different from the end piece, morphologies of the zygomatic area and the superior part of the nasolabial crease were determined largely by the skeleton in rest, implying the latter can be altered by orthopedic or orthodontic correction and the former better improved by cosmetic procedures to improve the beauty of smile.

  20. Determination of whole blood and plasma viscosity by means of flow curve analysis.

    PubMed

    Ruef, Peter; Gehm, Jutta; Gehm, Lothar; Felbinger, Claudia; Pöschl, Johannes; Kuss, Navina

    2014-01-01

    The LS300 viscometer permits automated measurements of viscosity at several shear rates of non-Newtonian fluids. We determined whole blood and plasma viscosity, aggregation, red blood cell deformability, and hematocrit of 66 healthy adults. The effects of the anticoagulants EDTA, heparin and citrate, and of centrifugation on blood viscosity (n=12) and red blood cell geometry (n=5) were investigated. With regard to the whole blood viscosity of adults, the best agreement was obtained by Casson's calculation compared to the methods of Ostwald, Bingham and Newton. The approximated flow curve of plasma showed only marginal differences between the method of Newton and Ostwald, whereas the latter gave the best quality of approximation. Centrifugation and the anticoagulants had a significant impact on whole blood viscosity and yield shear stress, whereas erythrocyte geometry remained unaffected. By linear regression of hematocrit with viscosity and yield shear stress, its impact on blood viscosity could be calculated in a hematocrit range of 0.32-0.50. Determination of whole blood viscosity should be performed in a standardized manner at several shear rates and without centrifugation of the blood samples. PMID:24968409

  1. Multivariate curve resolution for the analysis of remotely sensed thermal infrared hyperspectral images.

    SciTech Connect

    Haaland, David Michael; Stork, Christopher Lyle; Keenan, Michael Robert

    2004-07-01

    While hyperspectral imaging systems are increasingly used in remote sensing and offer enhanced scene characterization relative to univariate and multispectral technologies, it has proven difficult in practice to extract all of the useful information from these systems due to overwhelming data volume, confounding atmospheric effects, and the limited a priori knowledge regarding the scene. The need exists for the ability to perform rapid and comprehensive data exploitation of remotely sensed hyperspectral imagery. To address this need, this paper describes the application of a fast and rigorous multivariate curve resolution (MCR) algorithm to remotely sensed thermal infrared hyperspectral images. Employing minimal a priori knowledge, notably non-negativity constraints on the extracted endmember profiles and a constant abundance constraint for the atmospheric upwelling component, it is demonstrated that MCR can successfully compensate thermal infrared hyperspectral images for atmospheric upwelling and, thereby, transmittance effects. We take a semi-synthetic approach to obtaining image data containing gas plumes by adding emission gas signals onto real hyperspectral images. MCR can accurately estimate the relative spectral absorption coefficients and thermal contrast distribution of an ammonia gas plume component added near the minimum detectable quantity.

  2. Numerical analysis of thermal creep flow in curved channels for designing a prototype of Knudsen micropump

    NASA Astrophysics Data System (ADS)

    Leontidis, V.; Brandner, J. J.; Baldas, L.; Colin, S.

    2012-05-01

    The possibility to generate a gas flow inside a channel just by imposing a tangential temperature gradient along the walls without the existence of an initial pressure difference is well known. The gas must be under rarefied conditions, meaning that the system must operate between the slip and the free molecular flow regimes, either at low pressure or/and at micro/nano-scale dimensions. This phenomenon is at the basis of the operation principle of Knudsen pumps, which are actually compressors without any moving parts. Nowadays, gas flows in the slip flow regime through microchannels can be modeled using commercial Computational Fluid Dynamics softwares, because in this regime the compressible Navier-Stokes equations with appropriate boundary conditions are still valid. A simulation procedure has been developed for the modeling of thermal creep flow using ANSYS Fluent®. The implementation of the boundary conditions is achieved by developing User Defined Functions (UDFs) by means of C++ routines. The complete first order velocity slip boundary condition, including the thermal creep effects due to the axial temperature gradient and the effect of the wall curvature, and the temperature jump boundary condition are applied. The developed simulation tool is used for the preliminary design of Knudsen micropumps consisting of a sequence of curved and straight channels.

  3. Analyzing Exercise Behaviors during the College Years: Results from Latent Growth Curve Analysis

    PubMed Central

    Wittman, Werner

    2016-01-01

    The objective of this study is to analyze changes in the predictors of physical activity behavior among college students. The Theory of Planned Behavior served as its theoretical framework. Methods: Among an initial sample of 417 college students, 195 participants completed a validated questionnaire measuring attitudes, subjective norms, perceived control, intentions and self-reported physical activity, at the beginning and end of each of 3 college semesters. Latent growth curve modeling analyses were conducted to examine the relationships between the trajectories of changes in PA, intentions, attitudes, subjective norms, and perceived control. Results: Good fit indices supported the validity of the proposed longitudinal model (CFI > .97, RMSEA < .05). Changes in perceived control (γ = 0.57) were significantly linked with changes in intentions (p < .05). Perceived control (γ = 0.28) and intention growth (γ = 0.36) predicted behavior changes (p < .05). No gender differences were observed on attitudes, subjective norms and perceived control (p > .10). However, girls tend to have higher growth parameters on intentions and physical activity (p < .05). In summary, intentions and physical activity has significantly increased over 3 college semesters (growth parameters significant at p < .05). Conclusions: This study demonstrated that attitudes and perceived control are key determinants regarding the intentions of being active. On a longer term perspective, future physical activity interventions should focus on the enhancement of students’ perceived control. Such educational context should help in promoting the adoption of an active lifestyle during college. PMID:27124179

  4. Modeling and nonlinear hunting stability analysis of high-speed railway vehicle moving on curved tracks

    NASA Astrophysics Data System (ADS)

    Cheng, Yung-Chang; Lee, Sen-Yung; Chen, Hsing-Hao

    2009-07-01

    A heuristic nonlinear creep model is used to derive the nonlinear coupled differential equations of motion of a high-speed railway vehicle traveling on a curved track. The vehicle dynamics are modeled using a 21 degree-of-freedom (21-DOF) system which takes account of the lateral displacement and yaw angle of each wheelset, the lateral displacement, vertical displacement, roll angle and yaw angle of the truck frames, and the lateral displacement, vertical displacement, roll angle, pitch angle and yaw angle of the car body. To analyze the respective effects of the major system parameters on the vehicle dynamics, the 21-DOF system is reduced to 20-DOF, 14-DOF and 6-DOF models, respectively, by excluding designated subsets of the system parameters. The validity of the analytical models and the numerical solution procedure is confirmed by comparing the result obtained using the 6-DOF model for the critical velocity of a railway vehicle traveling on a tangent track with the solution presented in the literature. In general, the results obtained in this study show that the critical hunting speed derived using the 6-DOF or 14-DOF model is generally higher than that evaluated using the 20-DOF model. In addition, the critical hunting speed evaluated via the heuristic nonlinear creep model is lower than that derived using a linear creep model.

  5. Secondary flow structure in a model curved artery: 3D morphology and circulation budget analysis

    NASA Astrophysics Data System (ADS)

    Bulusu, Kartik V.; Plesniak, Michael W.

    2015-11-01

    In this study, we examined the rate of change of circulation within control regions encompassing the large-scale vortical structures associated with secondary flows, i.e. deformed Dean-, Lyne- and Wall-type (D-L-W) vortices at planar cross-sections in a 180° curved artery model (curvature ratio, 1/7). Magnetic resonance velocimetry (MRV) and particle image velocimetry (PIV) experiments were performed independently, under the same physiological inflow conditions (Womersley number, 4.2) and using Newtonian blood-analog fluids. The MRV-technique performed at Stanford University produced phase-averaged, three-dimensional velocity fields. Secondary flow field comparisons of MRV-data to PIV-data at various cross-sectional planes and inflow phases were made. A wavelet-decomposition-based approach was implemented to characterize various secondary flow morphologies. We hypothesize that the persistence and decay of arterial secondary flow vortices is intrinsically related to the influence of the out-of-plane flow, tilting, in-plane convection and diffusion-related factors within the control regions. Evaluation of these factors will elucidate secondary flow structures in arterial hemodynamics. Supported by the National Science Foundation under Grant Number CBET-0828903, and GW Center for Biomimetics and Bioinspired Engineering (COBRE). The MRV data were acquired at Stanford University in collaboration with Christopher Elkins and John Eaton.

  6. Stability and dynamic analysis of a slender column with curved longitudinal stiffeners

    NASA Technical Reports Server (NTRS)

    Lake, Mark S.

    1989-01-01

    The results of a stability design study are presented for a slender column with curved longitudinal stiffeners for large space structure applications. Linear stability analyses are performed using a link-plate representation of the stiffeners to determine stiffener local buckling stresses. Results from a set of parametric analyses are used to determine an approximate explicit expression for stiffener local buckling in terms of its geometric parameters. This expression along with other equations governing column stability and mass are assembled into a determinate system describing minimum mass stiffened column design. An iterative solution is determined to solve this system and a computer program incorporating this routine is presented. Example design problems are presented which verify the solution accuracy and illustrate the implementation of the solution routine. Also, observations are made which lead to a greatly simplified first iteration design equation relating the percent increase in column mass to the percent increase in column buckling load. From this, generalizations are drawn as to the mass savings offered by the stiffened column concept. Finally, the percent increase in fundamental column vibration frequency due to the addition of deployable stiffeners is studied.

  7. A novel three-dimensional smile analysis based on dynamic evaluation of facial curve contour.

    PubMed

    Lin, Yi; Lin, Han; Lin, Qiuping; Zhang, Jinxin; Zhu, Ping; Lu, Yao; Zhao, Zhi; Lv, Jiahong; Lee, Mln Kyeong; Xu, Yue

    2016-01-01

    The influence of three-dimensional facial contour and dynamic evaluation decoding on factors of smile esthetics is essential for facial beauty improvement. However, the kinematic features of the facial smile contour and the contribution from the soft tissue and underlying skeleton are uncharted. Here, the cheekbone-maxilla contour and nasolabial fold were combined into a "smile contour" delineating the overall facial topography emerges prominently in smiling. We screened out the stable and unstable points on the smile contour using facial motion capture and curve fitting, before analyzing the correlation between soft tissue coordinates and hard tissue counterparts of the screened points. Our finding suggests that the mouth corner region was the most mobile area characterizing smile expression, while the other areas remained relatively stable. Therefore, the perioral area should be evaluated dynamically while the static assessment outcome of other parts of the smile contour contribute partially to their dynamic esthetics. Moreover, different from the end piece, morphologies of the zygomatic area and the superior part of the nasolabial crease were determined largely by the skeleton in rest, implying the latter can be altered by orthopedic or orthodontic correction and the former better improved by cosmetic procedures to improve the beauty of smile. PMID:26911450

  8. Analysis of the Validity of Environmental Kuznets Curve for the Baltic States

    NASA Astrophysics Data System (ADS)

    Lapinskienė, Giedrė; Tvaronavičienė, Manuela; Vaitkus, Pranas

    2013-12-01

    The paper analyses a traditional Environmental Kuznets Curve (EKC) relationship between greenhouse gases (GHG) and gross domestic product (GDP), extending the research to include some additional factors, such as environmental tax, research and development expenditure, implicit tax rate on energy, primary production of coal and lignite, energy intensity of the economy taken from the Eurostat database. The EKC indicates that, at the early stages of economic growth, pollution increases with the growing use of resources, but when a certain level of income per capita is reached, the trend reverses so that, at a higher development stage, further economic growth leads to the improvement of the environment. In the first part of the research, the validity of the reduced EKC for the Baltic region for the period 1995-2008 is determined. In the second part, the impact of selected factors is statistically tested. In both cases, the standard cubic equation is used because it is believed that this model is the most accurate for the development stage of this region. The research results may be useful for climate change policy design.

  9. Vertically stratified two-phase flow in a curved channel: Insights from a domain perturbation analysis

    SciTech Connect

    Garg, P.; Picardo, J. R.; Pushpavanam, S.

    2014-07-15

    In this work, we investigate the fully developed flow field of two vertically stratified fluids (one phase flowing above the other) in a curved channel of rectangular cross section. The domain perturbation technique is applied to obtain an analytical solution in the asymptotic limit of low Reynolds numbers and small curvature ratios (the ratio of the width of the channel to its radius of curvature). The accuracy of this solution is verified by comparison with numerical simulations of the nonlinear equations. The flow is characterized by helical vortices within each fluid, which are driven by centrifugal forces. The number of vortices and their direction of circulation varies with the parameters of the system (the volume fraction, viscosity ratio, and Reynolds numbers). We identify nine distinct flow patterns and organize the parameter space into corresponding flow regimes. We show that the fully developed interface between the fluids is not horizontal, in general, but is deformed by normal stresses associated with the circulatory flow. The results are especially significant for flows in microchannels, where the Reynolds numbers are small. The mathematical results in this paper include an analytical solution to two coupled biharmonic partial differential equations; these equations arise in two-phase, two-dimensional Stokes flows.

  10. A novel three-dimensional smile analysis based on dynamic evaluation of facial curve contour

    PubMed Central

    Lin, Yi; Lin, Han; Lin, Qiuping; Zhang, Jinxin; Zhu, Ping; Lu, Yao; Zhao, Zhi; Lv, Jiahong; Lee, Mln Kyeong; Xu, Yue

    2016-01-01

    The influence of three-dimensional facial contour and dynamic evaluation decoding on factors of smile esthetics is essential for facial beauty improvement. However, the kinematic features of the facial smile contour and the contribution from the soft tissue and underlying skeleton are uncharted. Here, the cheekbone-maxilla contour and nasolabial fold were combined into a “smile contour” delineating the overall facial topography emerges prominently in smiling. We screened out the stable and unstable points on the smile contour using facial motion capture and curve fitting, before analyzing the correlation between soft tissue coordinates and hard tissue counterparts of the screened points. Our finding suggests that the mouth corner region was the most mobile area characterizing smile expression, while the other areas remained relatively stable. Therefore, the perioral area should be evaluated dynamically while the static assessment outcome of other parts of the smile contour contribute partially to their dynamic esthetics. Moreover, different from the end piece, morphologies of the zygomatic area and the superior part of the nasolabial crease were determined largely by the skeleton in rest, implying the latter can be altered by orthopedic or orthodontic correction and the former better improved by cosmetic procedures to improve the beauty of smile. PMID:26911450

  11. Evaluation of alternative model selection criteria in the analysis of unimodal response curves using CART

    USGS Publications Warehouse

    Ribic, C.A.; Miller, T.W.

    1998-01-01

    We investigated CART performance with a unimodal response curve for one continuous response and four continuous explanatory variables, where two variables were important (ie directly related to the response) and the other two were not. We explored performance under three relationship strengths and two explanatory variable conditions: equal importance and one variable four times as important as the other. We compared CART variable selection performance using three tree-selection rules ('minimum risk', 'minimum risk complexity', 'one standard error') to stepwise polynomial ordinary least squares (OLS) under four sample size conditions. The one-standard-error and minimum-risk-complexity methods performed about as well as stepwise OLS with large sample sizes when the relationship was strong. With weaker relationships, equally important explanatory variables and larger sample sizes, the one-standard-error and minimum-risk-complexity rules performed better than stepwise OLS. With weaker relationships and explanatory variables of unequal importance, tree-structured methods did not perform as well as stepwise OLS. Comparing performance within tree-structured methods, with a strong relationship and equally important explanatory variables, the one-standard-error-rule was more likely to choose the correct model than were the other tree-selection rules 1) with weaker relationships and equally important explanatory variables; and 2) under all relationship strengths when explanatory variables were of unequal importance and sample sizes were lower.

  12. Vibration analysis and structural identification of a curved multi-span viaduct

    NASA Astrophysics Data System (ADS)

    Benedettini, Francesco; Dilena, Michele; Morassi, Antonino

    2015-03-01

    This work continues a line of research aimed at the development of a dynamically based monitoring program of bridges in the area of Friuli Venezia Giulia, Italy. The main infrastructure of the survey program is the curved 15-span post-tensioned concrete viaduct considered in this paper. The viaduct consists of three continuous girders separated by expansion joints and supported on piers by means of elastomeric seismic isolators. Output-only vibration tests under traffic loads were carried out to extract the dynamic parameters of the first vibration modes of the structure. The experimental characteristics were compared with those predicted by a preliminary finite-element model. The properties of vibration modes with prevailing amplitudes along the radial and circumferential direction of the viaduct were described with poor precision. This disagreement required the calibration of the finite-element model through a tuning procedure based on modal data. In particular, the experience has shown that the dynamic behavior of the viaduct is strongly influenced by the mechanical properties of the bearing devices supporting the deck superstructures. The calibrated finite-element model can be used as a baseline model for future monitoring and condition assessment programs on this typology of infrastructures.

  13. A TRANSIT TIMING ANALYSIS OF NINE RISE LIGHT CURVES OF THE EXOPLANET SYSTEM TrES-3

    SciTech Connect

    Gibson, N. P.; Pollacco, D.; Simpson, E. K.; Barros, S.; Joshi, Y. C.; Todd, I.; Keenan, F. P.; Skillen, I.; Benn, C.; Christian, D.; Hrudkova, M.; Steele, I. A.

    2009-08-01

    We present nine newly observed transits of TrES-3, taken as part of a transit timing program using the RISE instrument on the Liverpool Telescope. A Markov-Chain Monte Carlo analysis was used to determine the planet-star radius ratio and inclination of the system, which were found to be R{sub p} /R {sub *} = 0.1664{sup +0.0011} {sub -0.0018} and i = 81.73{sup +0.13} {sub -0.04}, respectively, consistent with previous results. The central transit times and uncertainties were also calculated, using a residual-permutation algorithm as an independent check on the errors. A re-analysis of eight previously published TrES-3 light curves was conducted to determine the transit times and uncertainties using consistent techniques. Whilst the transit times were not found to be in agreement with a linear ephemeris, giving {chi}{sup 2} = 35.07 for 15 degrees of freedom, we interpret this to be the result of systematics in the light curves rather than a real transit timing variation. This is because the light curves that show the largest deviation from a constant period either have relatively little out-of-transit coverage or have clear systematics. A new ephemeris was calculated using the transit times and was found to be T{sub c} (0) = 2454632.62610 {+-} 0.00006 HJD and P = 1.3061864 {+-} 0.0000005 days. The transit times were then used to place upper mass limits as a function of the period ratio of a potential perturbing planet, showing that our data are sufficiently sensitive to have probed sub-Earth mass planets in both interior and exterior 2:1 resonances, assuming that the additional planet is in an initially circular orbit.

  14. Characterization of data error in time-domain induced polarization tomography based on the analysis of decay curves

    NASA Astrophysics Data System (ADS)

    Gallistl, Jakob; Flores-Orozco, Adrián; Bücker, Matthias; Williams, Kenneth H.

    2015-04-01

    Time-domain induced polarization (TDIP) measurements are based on the recording of remnant voltages after current switch off and thus typically suffer from low signal-to-noise ratios. The analysis of the discrepancy between normal and reciprocal measurements has demonstrated to be a suitable method to quantify the data error in TDIP data sets, permitting to compute images with enhanced resolution. However, due to time constraints, it is not always possible to collect reciprocal measurements. Hence, we propose an alternative methodology to quantify data error in TDIP, which is based on fitting model curves to the measured IP decay. Based on the goodness of the fit, we can identify outliers and derive error parameters for the inversion of the tomographic TDIP data. In order to assess the practicability of our approach, we present a comparison of imaging results obtained based on the fitting of decay curves with those obtained based on the analysis of repeated measurements and normal-reciprocal measurements. Inversion results presented here were computed for extensive field data sets collected at the Rifle (CO) and Shiprock (NM) test sites. These data sets include TDIP data collected with different devices and using different IP windows.

  15. Evaluation of pollutant loads from stormwater BMPs to receiving water using load frequency curves with uncertainty analysis.

    PubMed

    Park, Daeryong; Roesner, Larry A

    2012-12-15

    This study examined pollutant loads released to receiving water from a typical urban watershed in the Los Angeles (LA) Basin of California by applying a best management practice (BMP) performance model that includes uncertainty. This BMP performance model uses the k-C model and incorporates uncertainty analysis and the first-order second-moment (FOSM) method to assess the effectiveness of BMPs for removing stormwater pollutants. Uncertainties were considered for the influent event mean concentration (EMC) and the aerial removal rate constant of the k-C model. The storage treatment overflow and runoff model (STORM) was used to simulate the flow volume from watershed, the bypass flow volume and the flow volume that passes through the BMP. Detention basins and total suspended solids (TSS) were chosen as representatives of stormwater BMP and pollutant, respectively. This paper applies load frequency curves (LFCs), which replace the exceedance percentage with an exceedance frequency as an alternative to load duration curves (LDCs), to evaluate the effectiveness of BMPs. An evaluation method based on uncertainty analysis is suggested because it applies a water quality standard exceedance based on frequency and magnitude. As a result, the incorporation of uncertainty in the estimates of pollutant loads can assist stormwater managers in determining the degree of total daily maximum load (TMDL) compliance that could be expected from a given BMP in a watershed. PMID:22578429

  16. Development of Curved-Plate Elements for the Exact Buckling Analysis of Composite Plate Assemblies Including Transverse Shear Effects

    NASA Technical Reports Server (NTRS)

    McGowan, David M.; Anderson, Melvin S.

    1998-01-01

    The analytical formulation of curved-plate non-linear equilibrium equations that include transverse-shear-deformation effects is presented. A unified set of non-linear strains that contains terms from both physical and tensorial strain measures is used. Using several simplifying assumptions, linearized, stability equations are derived that describe the response of the plate just after bifurcation buckling occurs. These equations are then modified to allow the plate reference surface to be located a distance z(c), from the centroid surface which is convenient for modeling stiffened-plate assemblies. The implementation of the new theory into the VICONOPT buckling and vibration analysis and optimum design program code is described. Either classical plate theory (CPT) or first-order shear-deformation plate theory (SDPT) may be selected in VICONOPT. Comparisons of numerical results for several example problems with different loading states are made. Results from the new curved-plate analysis compare well with closed-form solution results and with results from known example problems in the literature. Finally, a design-optimization study of two different cylindrical shells subject to uniform axial compression is presented.

  17. Statistical signal analysis of the Phanerozoic ð13C curve: implications for Earth system evolution

    NASA Astrophysics Data System (ADS)

    Bachan, A.; Kump, L. R.; Payne, J.; Saltzman, M.; Thomas, E.

    2014-12-01

    In recent years, vast amounts of carbon isotopic data have been collected allowing the construction of the Phanerozoic δ13C curve in unprecedented detail. Our dataset comprises 8143 points spanning the last 541 m.y., with a mean spacing of 66 k.y. The average δ13C of Phanerozoic carbonate is 1 ‰ ± 2 ‰, in accordance with the canonical values measured in the past. However, the record also shows numerous, highly resolved, large (± 6 ‰) excursions whose magnitude declines through time, especially going into the late Mesozoic and Cenozoic. When the magnitude - distribution of the excursions is tabulated we find that it follows a power law: plotting the min-max differences vs. number of bins in which a particular value occurs reveals that the data fall on a semilogarithmic line with a slope of -0.23 and R2 = 0.99. The result is insensitive to outliers: smoothing the data with lowess, spline, Savitzky-Golay, and Butterworth filters yields similar results. The continuity from small variation to large perturbations, both positive and negative, suggests that, despite the numerous proposed causes for individual carbon isotopic evens, there is likely an underlying mechanism which governs the magnitude of δ13C response to perturbations. We suggest that a mechanism acting to amplify carbon cycle perturbations is the key to explaining the power-law distribution, and identify the anoxia-productivity feedback as the most likely candidate. Establishment of sulfidic conditions is accompanied by increased release of phosphate to the water column, which allows for further productivity, and thus acts as a destabilizing, positive, feedback. This feedback would act to increase carbon cycle swings irrespective of their proximal trigger. The decline in frequency of anoxic-sulfidic bottom waters in the world's oceans, and potential disappearance in the Late Mesozoic-Cenozoic, may account for a reduction in the Earth system's gain and increase in its resilience.

  18. The first multi-color light curve analysis of FI Lyn and new V and Rc light curve analysis for GN Boo, two W-subtype W Ursae Majoris systems

    NASA Astrophysics Data System (ADS)

    Barani, C.; Martignoni, M.; Acerbi, F.

    2015-08-01

    Here we present the first analysis of the B, V and Ic CCD light curves of the W UMa type eclipsing binary star FI Lyn obtained in the year 2009 (8 nights) and in the year 2010 (2 nights), and new CCD V and Rc light curves of the known contact eclipsing binary GN Boo obtained in 4 nights in May 2012. Our data permits us the determination of ten and six new times of minimum light respectively for FI Lyn and GN Boo and refine both the orbital periods of the systems to P = 0.3732612 days and P = 0.3016022 days. The periods of both the systems are variable. FI Lyn shows an increasing period at the rate of dP / dt 1.05 × 10-6 days yr-1 while GN Boo shows cyclic oscillations. The observed light curves are analyzed simultaneously with the Wilson-Devinney program analysis; the geometrical and photometric elements are derived. Our solutions show that FI Lyn and GN Boo belong to the W-subtype W Ursae Majoris contact binary class, consisting of a hotter, less massive primary star eclipsed at primary minimum with a primary spectral type of G1 and G8 and a companion of spectral type G3 and G4 respectively. We found, for FI Lyn a mass ratio of q = 2.58 , the degree of contact of f = 38.9 % , an orbital inclination of i = 71 ° .5 and a small temperature difference between the components of about Δ T = 150 K indicating a good thermal contact, while for GN Boo we found a mass ratio of q = 3.33 , the degree of contact of f = 24.3 % , an orbital inclination of i = 83 ° .6 and a difference between the components temperature of about Δ T = 620 K. The elements obtained from the W-D analysis are used to compute the physical parameters of the systems in order to study their evolutionary status.

  19. Recent trends in application of multivariate curve resolution approaches for improving gas chromatography-mass spectrometry analysis of essential oils.

    PubMed

    Jalali-Heravi, Mehdi; Parastar, Hadi

    2011-08-15

    Essential oils (EOs) are valuable natural products that are popular nowadays in the world due to their effects on the health conditions of human beings and their role in preventing and curing diseases. In addition, EOs have a broad range of applications in foods, perfumes, cosmetics and human nutrition. Among different techniques for analysis of EOs, gas chromatography-mass spectrometry (GC-MS) is the most important one in recent years. However, there are some fundamental problems in GC-MS analysis including baseline drift, spectral background, noise, low S/N (signal to noise) ratio, changes in the peak shapes and co-elution. Multivariate curve resolution (MCR) approaches cope with ongoing challenges and are able to handle these problems. This review focuses on the application of MCR techniques for improving GC-MS analysis of EOs published between January 2000 and December 2010. In the first part, the importance of EOs in human life and their relevance in analytical chemistry is discussed. In the second part, an insight into some basics needed to understand prospects and limitations of the MCR techniques are given. In the third part, the significance of the combination of the MCR approaches with GC-MS analysis of EOs is highlighted. Furthermore, the commonly used algorithms for preprocessing, chemical rank determination, local rank analysis and multivariate resolution in the field of EOs analysis are reviewed. PMID:21726708

  20. Bradford Curves.

    ERIC Educational Resources Information Center

    Rousseau, Ronald

    1994-01-01

    Discussion of informetric distributions shows that generalized Leimkuhler functions give proper fits to a large variety of Bradford curves, including those exhibiting a Groos droop or a rising tail. The Kolmogorov-Smirnov test is used to test goodness of fit, and least-square fits are compared with Egghe's method. (Contains 53 references.) (LRW)

  1. Football curves

    NASA Astrophysics Data System (ADS)

    Dupeux, Guillaume; Cohen, Caroline; Le Goff, Anne; Quéré, David; Clanet, Christophe

    2011-07-01

    Straight lines, zigzag, parabolas (possibly truncated), circles and spirals are the main curves which can be observed in football (in the European sense, soccer elsewhere). They are, respectively, associated to heavy kick, knuckleball, lob and banana kicks. We discuss their physical origin and determine their respective domain of existence.

  2. Multiscale Analysis of Soil Porosity from Hg Injection Curves in Soils from Minas Gerais, Brazil

    NASA Astrophysics Data System (ADS)

    Vidal Vázquez, E.; Miranda, J. G. V.; Paz-Ferreiro, J.

    2012-04-01

    The soil pore space is a continuum extremely variable in size, including structures smaller than nanometres and as large as macropores or cracks with millimetres or even centimetres size. Pore size distributions (PSDs) affects important soil functions, such as transmission and storage of water, and root growth. Direct and indirect measurements of PSDs are currently used to characterize soil structure. Mercury injection porosimetry is useful for assessing equivalent pore size diameters in the range from about 0,5 nm to 100 μm. Here, the multifractal formalism was employed to describe Hg injection curves measured in duplicate samples collected on 54 horizons from 19 profiles in Minas Gerais state, Brazil. Ten of the studied profiles were classified as Ferralsols (Latosols, Oxisols). Besides these, other wide different soil groups were sampled, including Nitisol, Acrisol, Alisol, Luvisol, Planosol, Cambisol, Andosol and Leptosol. Clay content varied from 4 to 86% and pore volume in the range from 100 to 0.005 μm was between 5.52 a 53.76 cm3100g-1. All the horizons taken on Ferralsols and Nitisols as well as in Bt argic horizons from Acrisol Alisol, Luvisol and Planosol clearly showed a bimodal pore size distribution. Pore volume in the range from 100 to 0.005 μm and microporosity (0,2-0.005 μm) showed a significant relationship with clay content an Al2O3. All the Hg injection data sets studied soil showed remarkably good scaling trends and could be fitted reasonably well with multifractal models. The capacity dimensions, D0, was not significantly different from the Euclidean dimension. The entropy dimension, D1, varied from 0.590 to 0.946 , whereas the Hölder exponent of order zero, α0was between 1.027 and 1.451, and these two parameters showed a lineal negatives relationship, as expected. The highest D1 values, ranging from 0.913 to 0.980, were obtained for the Leptosol, whereas the lowest D1 values, ranging from 0.641 to 0.766 corresponded to the Nitisol. This results reflect that most of the measure concentrated in a small size domain for the horizons sampled from the Nitisol, whereas for the Leptosol the measure was more evenly distributed. In general, multifractal indices have been found to be useful for assessing differences in pore size distributions of the studied soil types.

  3. Genetics Home Reference: autosomal recessive hypotrichosis

    MedlinePlus

    ... erythema), itchiness (pruritus), or missing patches of skin (erosions) on the scalp. In areas of poor hair ... recessive hypotrichosis with monilethrix hairs and congenital scalp erosions. J Invest Dermatol. 2006 Jun;126(6):1286- ...

  4. Genetics Home Reference: autosomal recessive congenital methemoglobinemia

    MedlinePlus

    ... In type II, growth is often slowed. Abnormal facial muscle movements can interfere with swallowing, which can lead ... recessive congenital methemoglobinemia type I typically reduce enzyme activity or stability. As a result, the enzyme cannot ...

  5. Systematic review of suicide in economic recession

    PubMed Central

    Oyesanya, Mayowa; Lopez-Morinigo, Javier; Dutta, Rina

    2015-01-01

    AIM: To provide a systematic update of the evidence concerning the relationship between economic recession and suicide. METHODS: A keyword search of Ovid Medline, Embase, Embase Classic, PsycINFO and PsycARTICLES was performed to identify studies that had investigated the association between economic recession and suicide. RESULTS: Thirty-eight studies met predetermined selection criteria and 31 of them found a positive association between economic recession and increased suicide rates. Two studies reported a negative association, two articles failed to find such an association, and three studies were inconclusive. CONCLUSION: Economic recession periods appear to increase overall suicide rates, although further research is warranted in this area, particularly in low income countries. PMID:26110126

  6. Have Employment Patterns in Recessions Changed?.

    ERIC Educational Resources Information Center

    Bowers, Norman

    1981-01-01

    A survey of postwar recessions shows that the increasing proportion of service sector jobs has moderated overall employment declines and that women in nontraditional jobs, Blacks, and youths bear a disproportionate share of job losses. (LRA)

  7. Autosomal recessive Klippel-Feil syndrome

    PubMed Central

    Silva, Elias Oliveira Da

    1982-01-01

    An inbred kindred with 12 cases of Klippel-Feil syndrome (seven females and five males) is reported. Inheritance is undoubtedly autosomal recessive. The main characteristic of the syndrome is fusion of cervical vertebrae. Images PMID:7077623

  8. High resolution melting curve analysis as a new tool for rapid identification of canine parvovirus type 2 strains.

    PubMed

    Bingga, Gali; Liu, Zhicheng; Zhang, Jianfeng; Zhu, Yujun; Lin, Lifeng; Ding, Shuangyang; Guo, Pengju

    2014-01-01

    A high resolution melting (HRM) curve method was developed to identify canine parvovirus type 2 (CPV-2) strains by nested PCR. Two sets of primers, CPV-426F/426R and CPV-87R/87F, were designed that amplified a 52 bp and 53 bp product from the viral VP2 capsid gene. The region amplified by CPV-426F/426R included the A4062G and T4064A mutations in CPV-2a, CPV-2b and CPV-2c. The region amplified by CPV-87F/87R included the A3045T mutation in the vaccine strains of CPV-2 and CPV-2a, CPV-2b and CPV-2c. Faecal samples were obtained from 30 dogs that were CPV antigen-positive. The DNA was isolated from the faecal samples and PCR-amplified using the two sets of primers, and genotyped by HRM curve analysis. The PCR-HRM assay was able to distinguish single nucleotide polymorphisms between CPV-2a, CPV-2b and CPV-2c using CPV-426F/426R. CPV-2a was distinguished from CPV-2b and CPV-2c by differences in the melting temperature. CPV-2b and CPV-2c could be distinguished based on the shape of the melting curve after generating heteroduplexes using a CPV-2b reference sample. The vaccine strains of CPV-2 were identified using CPV-87F/87R. Conventional methods for genotyping CPV strains are labor intensive, expensive or time consuming; the present PCR-based HRM assay might be an attractive alternative. PMID:25159576

  9. Load control - strain control isochronous stress - strain curves for high temperature nonlinear analysis

    NASA Astrophysics Data System (ADS)

    Bechtel, G. S.; Cook, T. S.

    1995-04-01

    Aircraft gas turbine components are subjected to severe operating conditions. High temperatures, large thermal strains, and mechanical loads combine to cause the material to undergo significant nonlinear behavior. In order to assure safe, durable components, it is necessary that analysis methods be available to predict the nonlinear deformation. General purpose finite element codes are available to perform elastic and viscoplastic analyses, but the analyses are expensive. Both large plastic and creep strain analyses can require significant computer resources, but typically a plastic solution is more economical to run than a time-stepping creep or viscoplastic model solution. For those applications where the deformation is principally time dependent, it is advantageous to include time-dependent creep effects in a 'constant time' or 'isochronous' analysis. Although this approach has been used in the past to estimate rupture life, this paper will present several significant new techniques for doing an isochronous analysis to analyze time-dependent deformation.

  10. Recessive Lethal Amber Suppressors in Yeast

    PubMed Central

    Brandriss, Marjorie C.; Soll, Larry; Botstein, David

    1975-01-01

    Recessive lethal amber suppressor mutations have been isolated in a diploid strain of Saccharomyces cerevisiae. Diploids carrying these suppressors upon sporulation yield asci with only two live spores, both lacking the suppressor. At least two classes of recessive lethal suppressors exist. Aneuploid strains carrying one wild type and one suppressor locus have been isolated and used in mapping studies; one suppressor maps on chromosome III, the other does not. PMID:1093932

  11. A Computer Program for Calculation of Calibration Curves for Quantitative X-Ray Diffraction Analysis.

    ERIC Educational Resources Information Center

    Blanchard, Frank N.

    1980-01-01

    Describes a FORTRAN IV program written to supplement a laboratory exercise dealing with quantitative x-ray diffraction analysis of mixtures of polycrystalline phases in an introductory course in x-ray diffraction. Gives an example of the use of the program and compares calculated and observed calibration data. (Author/GS)

  12. Simulating coal preparation distribution curves

    SciTech Connect

    Reid, K.J.; Lu Maixi; Zhang Shenggui

    1985-01-01

    Using a microcomputer a set of computer programs has been systematically developed to simulate distribution curves, calculate the performance characteristics of coal cleaning devices, display the distribution curve shapes on graphic screen or plotter and perform a reliability analysis of the simulated partition curves. Distribution curves for 81 sets of coal cleaning data covering six coal washing methods were studied using six different mathematical models. The importance of selecting a distribution curve model based on the shape characteristics of the curve as well as the normal statistical tests is illustrated. 8 references.

  13. On the Link Between Streamflow Transit Time and Hydrograph Recession

    NASA Astrophysics Data System (ADS)

    James, A. L.; McDonnell, J. J.; McGuire, K. J.

    2007-12-01

    In catchment hydrology, new interest has recently focused on estimation of transit time of water as a diagnostic characteristic of a watershed. Regarded as a fundamental control on water chemistry and a key descriptor of storage, estimates of transit time also offer an additional form of data with which to test watershed models. However, as identified in a recent literature review, many challenges in the estimation of a mean transit time (MTT) as well as its statistical distribution remain. While recent papers have addressed the assumptions implicit in the mathematical lumped parameter flow models for tracers like δ18O, few studies have tried to estimate MTT using other more easily available methods. As a result, measurement of MTT remains difficult with today's technologies. In this paper, we further test a method of baseflow hydrograph recession analysis to estimate MTT for the well characterized H.J. Andrews watersheds, a Long Term Ecological Research (LTER) station located in Oregon's Cascade Mountains, USA. The six H.J. Andrews watersheds range in size from 0.102 to 62.4 km2. We compared the simplified baseflow recession-based method and its assumptions against the stable isotope δ18O tracer-based convolution model previously applied to these catchments. The baseflow recession method estimates MTT values ranging from 1.6 to 2.4 years, within the evaluated uncertainty of the convolution models for five of the six watersheds. The analysis presented in this briefing provides encouraging evidence that the less costly baseflow hydrograph recession analysis may be potentially as useful in predicting this fundamental diagnostic of hydrologic behavior for some catchments.

  14. Solute transport analysis of bromide, uranin and LiCl using breakthrough curves from aquifer sediment

    NASA Astrophysics Data System (ADS)

    Vereecken, H.; Jaekel, U.; Esser, O.; Nitzsche, O.

    1999-07-01

    The transport behavior of lithium, uranin, bromide and chloride was studied in column experiments using sediment from an unconfined aquifer at the Krauthausen test site. Sorption isotherms of uranin, bromide and chloride were determined in batch experiments. In addition, a sorption/desorption isotherm of uranin was determined. Inverse parameter estimation and asymptotic analysis of solute transport processes were used to interpret measured BTCs. The log transformed BTCs of bromide and chloride showed a linear decrease of the tailing part with time. Depending on the shape of the tail in the BTCs, a CDE with retardation or a mobile/immobile model was adjusted successfully. Measured uranin BTCs were described using either the CDE with hysteretic Freundlich sorption or the CDE with linear kinetic sorption. In addition, one of the measured uranin BTCs provided evidence for the presence of nonlinear nonequilibrium sorption. The discrimination and identification of the different types of sorption processes was based to a large extent on asymptotic analysis. However, in a few experiments asymptotic analysis did not provide information on the sorption process because the tailing concentrations fell below the detection limit before convergence to one of the asymptotic solutions could be observed. For none of these cases, the models analyzed in this work were able to describe the complete BTCs (including the tail). For two BTCs showing sorption hysteresis, the observed concentrations could be predicted using data from independent measurements almost without parameter fitting. Only a slight modification of the distribution coefficient was needed in one case. Lithium transport could be described either by Freundlich sorption or linear kinetic sorption. Field BTCs of uranin showed a qualitatively similar behavior as the BTCs observed in column experiments. Evaluation of the slope of log-log transformed field BTCs suggested that uranin sorption may be described by a nonlinear nonequilibrium sorption or hysteretic Freundlich sorption model.

  15. Mathematical Analysis for Peristaltic Flow of Two Phase Nanofluid in a Curved Channel

    NASA Astrophysics Data System (ADS)

    Nadeem, S.; Iqra, Shahzadi

    2015-11-01

    This paper describes the theoretical analysis for peristaltic motion of water base nanofluid containing distinct types of the nanoparticles like Cu, TiO2, and Al2O3. Equations of nano fluid are modelled and simplified by constructing the suppositions of low Reynolds number as well as long wave length. The reduced equations are solved exactly. Solutions are represented through graphs. Outcomes for the velocity, temperature, pressure rise and stream lines are analyzed graphically. The work presented here is based on the fictitious values, however some other values can be tested experimentally.

  16. BAYESIAN WAVELET-BASED CURVE CLASSIFICATION VIA DISCRIMINANT ANALYSIS WITH MARKOV RANDOM TREE PRIORS

    PubMed Central

    Stingo, Francesco C.; Vannucci, Marina; Downey, Gerard

    2014-01-01

    Discriminant analysis is an effective tool for the classification of experimental units into groups. When the number of variables is much larger than the number of observations it is necessary to include a dimension reduction procedure into the inferential process. Here we present a typical example from chemometrics that deals with the classification of different types of food into species via near infrared spectroscopy. We take a nonparametric approach by modeling the functional predictors via wavelet transforms and then apply discriminant analysis in the wavelet domain. We consider a Bayesian conjugate normal discriminant model, either linear or quadratic, that avoids independence assumptions among the wavelet coefficients. We introduce latent binary indicators for the selection of the discriminatory wavelet coefficients and propose prior formulations that use Markov random tree (MRT) priors to map scale-location connections among wavelets coefficients. We conduct posterior inference via MCMC methods, we show performances on our case study on food authenticity and compare results to several other procedures.. PMID:24761126

  17. Molecular component distribution imaging of living cells by multivariate curve resolution analysis of space-resolved Raman spectra.

    PubMed

    Ando, Masahiro; Hamaguchi, Hiro-o

    2014-01-01

    Label-free Raman microspectroscopy combined with a multivariate curve resolution (MCR) analysis can be a powerful tool for studying a wide range of biomedical molecular systems. The MCR with the alternating least squares (MCR-ALS) technique, which retrieves the pure component spectra from complicatedly overlapped spectra, has been successfully applied to in vivo and molecular-level analysis of living cells. The principles of the MCR-ALS analysis are reviewed with a model system of titanium oxide crystal polymorphs, followed by two examples of in vivo Raman imaging studies of living yeast cells, fission yeast, and budding yeast. Due to the non-negative matrix factorization algorithm used in the MCR-ALS analysis, the spectral information derived from this technique is just ready for physical and/or chemical interpretations. The corresponding concentration profiles provide the molecular component distribution images (MCDIs) that are vitally important for elucidating life at the molecular level, as stated by Schroedinger in his famous book, "What is life?" Without any a priori knowledge about spectral profiles, time- and space-resolved Raman measurements of a dividing fission yeast cell with the MCR-ALS elucidate the dynamic changes of major cellular components (lipids, proteins, and polysaccharides) during the cell cycle. The MCR-ALS technique also resolves broadly overlapped OH stretch Raman bands of water, clearly indicating the existence of organelle-specific water structures in a living budding yeast cell. PMID:24108582

  18. Vibrational spectroscopic image analysis of biological material using multivariate curve resolution-alternating least squares (MCR-ALS).

    PubMed

    Felten, Judith; Hall, Hardy; Jaumot, Joaquim; Tauler, Romà; de Juan, Anna; Gorzsás, András

    2015-02-01

    Raman and Fourier transform IR (FTIR) microspectroscopic images of biological material (tissue sections) contain detailed information about their chemical composition. The challenge lies in identifying changes in chemical composition, as well as locating and assigning these changes to different conditions (pathology, anatomy, environmental or genetic factors). Multivariate data analysis techniques are ideal for decrypting such information from the data. This protocol provides a user-friendly pipeline and graphical user interface (GUI) for data pre-processing and unmixing of pixel spectra into their contributing pure components by multivariate curve resolution-alternating least squares (MCR-ALS) analysis. The analysis considers the full spectral profile in order to identify the chemical compounds and to visualize their distribution across the sample to categorize chemically distinct areas. Results are rapidly achieved (usually <30-60 min per image), and they are easy to interpret and evaluate both in terms of chemistry and biology, making the method generally more powerful than principal component analysis (PCA) or heat maps of single-band intensities. In addition, chemical and biological evaluation of the results by means of reference matching and segmentation maps (based on k-means clustering) is possible. PMID:25569330

  19. Molecular component distribution imaging of living cells by multivariate curve resolution analysis of space-resolved Raman spectra

    NASA Astrophysics Data System (ADS)

    Ando, Masahiro; Hamaguchi, Hiro-o.

    2014-01-01

    Label-free Raman microspectroscopy combined with a multivariate curve resolution (MCR) analysis can be a powerful tool for studying a wide range of biomedical molecular systems. The MCR with the alternating least squares (MCR-ALS) technique, which retrieves the pure component spectra from complicatedly overlapped spectra, has been successfully applied to in vivo and molecular-level analysis of living cells. The principles of the MCR-ALS analysis are reviewed with a model system of titanium oxide crystal polymorphs, followed by two examples of in vivo Raman imaging studies of living yeast cells, fission yeast, and budding yeast. Due to the non-negative matrix factorization algorithm used in the MCR-ALS analysis, the spectral information derived from this technique is just ready for physical and/or chemical interpretations. The corresponding concentration profiles provide the molecular component distribution images (MCDIs) that are vitally important for elucidating life at the molecular level, as stated by Schroedinger in his famous book, "What is life?" Without any a priori knowledge about spectral profiles, time- and space-resolved Raman measurements of a dividing fission yeast cell with the MCR-ALS elucidate the dynamic changes of major cellular components (lipids, proteins, and polysaccharides) during the cell cycle. The MCR-ALS technique also resolves broadly overlapped OH stretch Raman bands of water, clearly indicating the existence of organelle-specific water structures in a living budding yeast cell.

  20. Automatic and objective oral cancer diagnosis by Raman spectroscopic detection of keratin with multivariate curve resolution analysis

    PubMed Central

    Chen, Po-Hsiung; Shimada, Rintaro; Yabumoto, Sohshi; Okajima, Hajime; Ando, Masahiro; Chang, Chiou-Tzu; Lee, Li-Tzu; Wong, Yong-Kie; Chiou, Arthur; Hamaguchi, Hiro-o

    2016-01-01

    We have developed an automatic and objective method for detecting human oral squamous cell carcinoma (OSCC) tissues with Raman microspectroscopy. We measure 196 independent Raman spectra from 196 different points of one oral tissue sample and globally analyze these spectra using a Multivariate Curve Resolution (MCR) analysis. Discrimination of OSCC tissues is automatically and objectively made by spectral matching comparison of the MCR decomposed Raman spectra and the standard Raman spectrum of keratin, a well-established molecular marker of OSCC. We use a total of 24 tissue samples, 10 OSCC and 10 normal tissues from the same 10 patients, 3 OSCC and 1 normal tissues from different patients. Following the newly developed protocol presented here, we have been able to detect OSCC tissues with 77 to 92% sensitivity (depending on how to define positivity) and 100% specificity. The present approach lends itself to a reliable clinical diagnosis of OSCC substantiated by the “molecular fingerprint” of keratin. PMID:26806007

  1. Analysis of the photoelectric light curve and the orbital period variations of the binary system UU Andromedae

    NASA Astrophysics Data System (ADS)

    Manzoori, D.; Abbasvand, S.; Najafinezhad, F.

    2015-08-01

    In this work, the analysis of the photoelectric light curve (LC) in the broad-band filter (400-700 nm) for the UU And system was carried out using the PHOEBE program (vers. 0.31a). The absolute dimensions of the system are determined and its evolution is discussed. Moreover, the period changes of the system are studied using updated O-C data, which shows a cyclic change with a period of P_mod=18 yr. This was attributed to a magnetic activity cycle operating in this system. In addition to the cyclic change, a long-term secular variation due to mass transfer from the secondary to the primary component with a rate of 6.17 × 10-9 M⊙ yr-1 was also detected.

  2. Statistical methods for pavement performance curve building, historical analysis, data sampling and storage. Final report, May 1997--July 1998

    SciTech Connect

    Zimmerman, K.A.; Bahulkar, A.M.

    1998-08-01

    The use of a pavement management system provides a state highway agency with the tools necessary to conduct a multi-year analysis of the maintenance and rehabilitation needs within the state based on both current needs and expected future conditions. In order to adequately predict future conditions, pavement performance models must be developed to reflect the deterioration trends of the agency`s pavements. At the time the SDDOT pavement management system was implemented in 1994, the Department developed a new condition rating system to evaluate the existing conditions of the state maintained pavements. At the same time, expert-based pavement performance models were developed to approximate the deterioration patterns of the highways based on pavement families (groupings of pavements with similar characteristics). A recommendation from that study (SD93-14) was to update the curves based on historical performance once sufficient data had been collected.

  3. A Latent Growth Curve Analysis of Early and Increasing Peer Victimization as Predictors of Mental Health Across Elementary School

    PubMed Central

    Rudolph, Karen D.; Troop-Gordon, Wendy; Hessel, Elenda T.; Schmidt, Jennifer D.

    2011-01-01

    Peer victimization has been implicated as a traumatic stressor that compromises children’s long-term mental health, yet a dearth of prospective research specifically demonstrates lasting effects of early victimization. This research examined whether early (2nd grade) victimization and increasing (2nd – 5th grade) victimization independently predicted depressive symptoms and aggressive behavior (overt and relational) in 5th grade. Participants included 433 children (238 girls, 195 boys). Children reported on peer victimization and depressive symptoms; teachers reported on peer victimization and aggressive behavior. Latent growth curve analysis revealed that both early and increasing victimization made unique contributions to subsequent depressive symptoms and aggressive behavior. Relational aggression was particularly likely to follow victimization in girls. PMID:21229448

  4. Lineage-specific detection of influenza B virus using real-time polymerase chain reaction with melting curve analysis.

    PubMed

    Tewawong, Nipaporn; Chansaenroj, Jira; Klinfueng, Sirapa; Vichiwattana, Preeyaporn; Korkong, Sumeth; Thongmee, Thanunrat; Theamboonlers, Apiradee; Payungporn, Sunchai; Vongpunsawad, Sompong; Poovorawan, Yong

    2016-06-01

    Influenza B viruses comprise two lineages, Victoria (B/Vic) and Yamagata (B/Yam), which co-circulate globally. The surveillance data on influenza B virus lineages in many countries often underestimate the true prevalence due to the lack of a rapid, accurate, and cost-effective method for virus detection. We have developed a real-time PCR with melting curve analysis for lineage-specific differential detection of influenza B virus. By amplifying a region of the hemagglutinin gene using real-time PCR with SYBR Green I dye, B/Vic and B/Yam could be differentiated based on their melting temperature peaks. This method was efficient (B/Vic = 93.2 %; B/Yam 97.7 %), sensitive (B/Vic, 94.6 %; B/Yam, 96.3 %), and specific (B/Vic, 97.7 %; B/Yam, 97.1 %). The lower detection limit was 10(2) copies per microliter. The assay was evaluated using 756 respiratory specimens that were positive for influenza B virus, obtained between 2010 and 2015. The incidence of influenza B virus was approximately 18.9 % of all influenza cases, and the percentage was highest among children aged 6-17 years (7.57 %). The overall percentage of mismatched influenza B vaccine was 21.1 %. Our findings suggest that real-time PCR with melting curve analysis can provide a rapid, simple, and sensitive lineage-specific influenza B virus screening method to facilitate influenza surveillance. PMID:26923928

  5. Assessing catchment hydrological functioning using discharge recession analysis based on the Kirchner's method. A case study in the Ardèche catchment (France)

    NASA Astrophysics Data System (ADS)

    Adamovic, Marko; Braud, Isabelle; Branger, Flora; Krier, Robert

    2013-04-01

    Catchments show a high degree of heterogeneity and variability, both in space and time. In order to deal with spatial heterogeneity and process variability in more efficient and more "natural and realistic" manner, model simplifications are needed. Governing equations such as the Darcy or Richards' equation, which are inherent in many hydrological models, are suitable for local scales. However, their application at much larger scales (e.g. catchment scale) remains problematic. The linear reservoir is a well-known and common approach in many catchment-based hydrological models. However, reality shows that those linear equations might not be representative enough for describing hydrological catchment behavior. Kirchner (2009), proposed a simple approach representing catchment behavior as a non-linear reservoir model, assuming that discharge at the outlet is only a function of catchment storage. He also proposed a method to determine non-linear reservoir parameters for this simple bucket model. The objective of this study is to investigate whether this approach is applicable to the Ardèche catchment (2355 km2), located in the southern part of France. The catchment is influenced by a Mediterranean climate with seasonal heavy rainfall events during autumn. The northern and north-western part of the catchment is characterized by steep slopes and igneous and metamorphic rock formations. A further objective is to relate the estimated parameters of the first-order dynamical system to catchment characteristics, in order to be able to develop a distributed model, adapted to the catchment response variability. The challenge for the Kirchner's method is the high geological and pedological heterogeneity of the Ardèche basin. We apply the Kirchner's method to 6 sub-catchments of the Ardèche ranging from 3.9 to 200 km2 using hourly rainfall and discharge data, in order to identify the discharge sensitivity function. We use the obtained corresponding parameters in a simple bucket model similar to the one proposed by Kirchner (2009). To have more representative potential evapotranspiration data used in the model, we introduce crop coefficient seasonality to better represent the data. Performance measurements with the Nash-Sutcliffe coefficient show performances above 80 %. These results clearly indicate that timing and magnitude of simulated discharge is correctly reproduced by the model. Additionally we assess the impact of the seasonality on the model parameterization yielding similar results in the discharge analysis. Our work shows that Kirchner's method can be applied successfully in the Ardèche catchment. Eventually, we observe that geology may be highlighted as a predictor that dominates the overall hydrological response in the basin. Kirchner, J. W. (2009), Catchments as simple dynamical systems: Catchment characterization, rainfall-runoff modeling, and doing hydrology backward, Water Resour. Res., 45, W02429, doi:10.1029/2008WR006912

  6. Development of Curved-Plate Elements for the Exact Buckling Analysis of Composite Plate Assemblies Including Transverse-Shear Effects

    NASA Technical Reports Server (NTRS)

    McGowan, David M.

    1999-01-01

    The analytical formulation of curved-plate non-linear equilibrium equations including transverse-shear-deformation effects is presented. A unified set of non-linear strains that contains terms from both physical and tensorial strain measures is used. Linearized, perturbed equilibrium equations (stability equations) that describe the response of the plate just after buckling occurs are derived. These equations are then modified to allow the plate reference surface to be located a distance z(sub c) from the centroidal surface. The implementation of the new theory into the VICONOPT exact buckling and vibration analysis and optimum design computer program is described. The terms of the plate stiffness matrix using both classical plate theory (CPT) and first-order shear-deformation plate theory (SDPT) are presented. The effects of in-plane transverse and in-plane shear loads are included in the in-plane stability equations. Numerical results for several example problems with different loading states are presented. Comparisons of analyses using both physical and tensorial strain measures as well as CPT and SDPT are made. The computational effort required by the new analysis is compared to that of the analysis currently in the VICONOPT program. The effects of including terms related to in-plane transverse and in-plane shear loadings in the in-plane stability equations are also examined. Finally, results of a design-optimization study of two different cylindrical shells subject to uniform axial compression are presented.

  7. Management and prevention of gingival recession.

    PubMed

    Merijohn, George K

    2016-06-01

    Gingival recession is highly prevalent worldwide. It increases the risk for root caries and can interfere with patient comfort, function and esthetics. Progressive gingival recession also increases the risk of tooth loss secondary to clinical attachment loss. Although mitigating the causes of gingival recession decreases its incidence and severity, implementing practical management and prevention strategies in the clinical setting can be challenging. Identification of susceptible patients and evaluating them for the presence of modifiable risk exposures are essential first steps in developing action plans for appropriate interventions. This article reviews these steps and introduces chairside tools that can help in the selection of interventions designed to reduce the risk of future gingival recession and may also facilitate patient communication. Practical decision-making criteria are proposed for when and how to monitor gingival recession, for deciding when a patient is a candidate for surgical evaluation or referral to a periodontist, and, if surgery is the treatment of choice, what should be considered as key surgical outcome objectives. PMID:27045439

  8. Aeroacoustical Study of the Tgv Pantograph Recess

    NASA Astrophysics Data System (ADS)

    NOGER, C.; PATRAT, J. C.; PEUBE, J.; PEUBE, J. L.

    2000-03-01

    The general focus of this aerodynamic noise research, induced by turbulent incompressible flow, is to improve our knowledge of acoustic production mechanisms in the TGV pantograph recess in order to be able to reduce the radiated noise. This work is performed under contract with SNCF as a part of the German-French Cooperation DEUFRAKO K2, and is supported by French Ministries for Transport and Research. Previous studies on TGV noise source locations (DEUFRAKO K) have identified the pantograph recess as one of the important aerodynamic noise sources, for speeds higher than 300 km/h, due to flow separation. The pantograph recess is a very complex rectangular cavity, located both on the power car and the first coach roofs of the TGV, and has not been studied before due to the complex shapes. Its aeroacoustic features are investigated experimentally in a low-subsonic wind tunnel, on a realistic 1/7th scale mock-up both with and without pantographs. Flow velocities, estimated with hot-wire anemometry, and parietal visualizations show the flow to reattach on the recess bottom wall and to separate again at the downstream face. Wall pressure fluctuations and acoustic measurements using 14 and 12 in microphones respectively are also measured to qualify the flow: no aerodynamic or acoustic oscillations are observed. The study indicates that the pantograph recess has a different behaviour compared to the usual cavity grazing flows.

  9. Cone-beam computed tomography analysis of curved root canals after mechanical preparation with three nickel-titanium rotary instruments

    PubMed Central

    Elsherief, Samia M.; Zayet, Mohamed K.; Hamouda, Ibrahim M.

    2013-01-01

    Cone beam computed tomography is a 3-dimensional high resolution imaging method. The purpose of this study was to compare the effects of 3 different NiTi rotary instruments used to prepare curved root canals on the final shape of the curved canals and total amount of root canal transportation by using cone-beam computed tomography. A total of 81 mesial root canals from 42 extracted human mandibular molars, with a curvature ranging from 15 to 45 degrees, were selected. Canals were randomly divided into 3 groups of 27 each. After preparation with Protaper, Revo-S and Hero Shaper, the amount of transportation and centering ability that occurred were assessed by using cone beam computed tomography. Utilizing pre- and post-instrumentation radiographs, straightening of the canal curvatures was determined with a computer image analysis program. Canals were metrically assessed for changes (surface area, changes in curvature and transportation) during canal preparation by using software SimPlant; instrument failures were also recorded. Mean total widths and outer and inner width measurements were determined on each central canal path and differences were statistically analyzed. The results showed that all instruments maintained the original canal curvature well with no significant differences between the different files (P = 0.226). During preparation there was failure of only one file (the protaper group). In conclusion, under the conditions of this study, all instruments maintained the original canal curvature well and were safe to use. Areas of uninstrumented root canal wall were left in all regions using the various systems. PMID:23885273

  10. MOST light-curve analysis of the γ Doradus pulsator HR 8799, showing resonances and amplitude variations

    NASA Astrophysics Data System (ADS)

    Sódor, Á.; Chené, A.-N.; De Cat, P.; Bognár, Zs.; Wright, D. J.; Marois, C.; Walker, G. A. H.; Matthews, J. M.; Kallinger, T.; Rowe, J. F.; Kuschnig, R.; Guenther, D. B.; Moffat, A. F. J.; Rucinski, S. M.; Sasselov, D.; Weiss, W. W.

    2014-08-01

    Context. The central star of the HR 8799 system is a γ Doradus-type pulsator. The system harbours four planetary-mass companions detected by direct imaging, and is a good solar system analogue. The masses of the companions are not accurately known because the estimation depends greatly on the age of the system, which is also not known with sufficient accuracy. Asteroseismic studies of the star might help to better constrain the age of HR 8799. We organized an extensive photometric and multi-site spectroscopic observing campaign to study the pulsations of the central star. Aims: The aim of the present study is to investigate the pulsation properties of HR 8799 in detail via the ultra-precise 47 d nearly continuous photometry obtained with the Microvariability and Oscillations in STars (MOST) space telescope, and to find as many independent pulsation modes as possible, which is the prerequisite for an asteroseismic age determination. Methods: We carried out Fourier analysis of the wide-band photometric time series. Results: We find that resonance and sudden amplitude changes characterize the pulsation of HR 8799. The dominant frequency is always at f1 = 1.978 d-1.Many multiples of one-ninth of the dominant frequency appear in the Fourier spectrum of the MOST data: n/9 f1, where n = {1,2,3,4,5,6,7,8,9,10,13,14,17,18}. Our analysis also reveals that many of these peaks show strong amplitude decrease and phase variations even on the 47 d time scale. The dependencies between the pulsation frequencies of HR 8799 make the planned subsequent asteroseismic analysis rather difficult. We point out some resemblance between the light curve of HR 8799 and the modulated pulsation light curves of Blazhko RR Lyrae stars. Based on data from the MOST satellite, a Canadian Space Agency mission, jointly operated by Dynacon Inc., the University of Toronto Institute for Aerospace Studies and the University of British Columbia, with the assistance of the University of Vienna.

  11. Siblings with recessive oculopharyngeal muscular dystrophy.

    PubMed

    Hebbar, Srisha; Webberley, Michael J; Lunt, Peter; Robinson, David O

    2007-03-01

    Oculopharyngeal muscular dystrophy (OPMD) is a late onset myopathy usually presenting in the 5th or 6th decade of life with progressive ptosis, dysphagia and proximal muscle weakness. It is usually dominantly inherited; however, a rare recessive form has also been described although documentation of such cases in the literature is very sparse. Here we report two siblings with recessive OPMD, in one of whom the clinical picture is complicated by ankylosing spondilitis and pneumonia. They exhibit later onset and milder symptoms than is typical for patients with dominantly inherited OPMD. This and the possibility that OPMD may be masked by symptoms of other diseases of the elderly may account for the paucity of cases of recessive OPMD reported in the literature. PMID:17296297

  12. NEW BEST1 MUTATIONS IN AUTOSOMAL RECESSIVE BESTROPHINOPATHY

    PubMed Central

    FUNG, ADRIAN T.; YZER, SUZANNE; GOLDBERG, NAOMI; WANG, HAO; NISSEN, MICHAEL; GIOVANNINI, ALFONSO; MERRIAM, JOANNA E.; BUKANOVA, ELENA N.; CAI, CAROLYN; YANNUZZI, LAWRENCE A.; TSANG, STEPHEN H.; ALLIKMETS, RANDO

    2015-01-01

    Purpose To report the ocular phenotype in patients with autosomal recessive bestrophinopathy and carriers, and to describe novel BEST1 mutations. Methods Patients with clinically suspected and subsequently genetically proven autosomal recessive bestrophinopathy underwent full ophthalmic examination and investigation with fundus autofluorescence imaging, spectral domain optical coherence tomography, electroretinography, and electrooculography. Mutation analysis of the BEST1 gene was performed through direct Sanger sequencing. Results Five affected patients from four families were identified. Mean age was 16 years (range, 6–42 years). All affected patients presented with reduced visual acuity and bilateral, hyperautofluorescent subretinal yellowish deposits within the posterior pole. Spectral domain optical coherence tomography demonstrated submacular fluid and subretinal vitelliform material in all patients. A cystoid maculopathy was seen in all but one patient. In 1 patient, the location of the vitelliform material was seen to change over a follow-up period of 3 years despite relatively stable vision. Visual acuity and fundus changes were unresponsive to topical and systemic carbonic anhydrase inhibitors and systemic steroids. Carriers had normal ocular examinations including normal fundus autofluorescence. Three novel mutations were detected. Conclusion Three novel BEST1 mutations are described, suggesting that many deleterious variants in BEST1 resulting in haploinsufficiency are still unknown. Mutations causing autosomal recessive bestrophinopathy are mostly located outside of the exons that usually harbor vitelliform macular dystrophy–associated dominant mutations. PMID:25545482

  13. Cyclic Fatigue Testing of Three Different Rotary Nickel Titanium Endodontic Instruments in Simulated Curved Canals - An in Vitro Sem Analysis

    PubMed Central

    Reddy Y., Pallavi; S., Kavita; Subbarao, C.V.

    2014-01-01

    Introduction: Instrument separation is a serious concern in endodontics. Stainless steel instruments usually deform before they separate whereas Nickel Titanium instruments do not show any sign of deformation. Aim: of the present study was to compare the cyclic rotations needed to fracture three different rotary nickel titanium endodontic instruments namely Profile, K3 Endo, RaCe in simulated curved canals having 2 different radii of curvature i.e., 5mm &10mm with a constant angle of curvature of 45°. The fractured surfaces were analysed using Scanning Electron Microscopy (SEM). Materials and Methods: Sixty rotary nickel titanium instruments were used for analysis in this study. The instruments were divided into three groups based on the different cross sections. Three groups were further divided into two sub groups based on radius of curvatures. Ten files were tested in each sub-group. Results: Group A (Profile) showed increased number of cycles to failure i.e., low incidence of fracture at both the radii of curvatures when compared to the other two groups. SEM analysis showed that in Group A the fractured surface of the files tested were characterized by the presence of smooth area on their edges associated with nucleation and slow fatigue crack propagation when compared to Group B and C. Therefore Group A (Profile) demonstrated least cyclic fatigue when compared to the other two groups. PMID:24701537

  14. A historical perspective of the effect of the great recession on hospitals.

    PubMed

    Shortt, Janet

    2014-08-01

    At 18 months, the Great Recession of December 2007 to June 2009 is the longest recession since World War II. The recession led to soaring unemployment, resulting in loss of employment-based health insurance for millions of people. In addition to seeing increases in uninsured patients, hospitals experienced losses in their investment portfolios, which in turn increased bad debt, charity care, and uncompensated care nationwide. Hospital executives began to devise cost-cutting strategies to balance the rising debt, such as standardizing medical equipment, cutting staff positions, and delaying construction projects and capital expenditures as well as implementing value analysis strategies. The recession is officially over, and, although economic recovery has been slow and unemployment continues to be an issue, hospitals' net revenue started improving as of 2009 and hospital construction started increasing in 2010. Still, caution is warranted in the postrecession climate, because it is unknown what effects will be seen when the Baby Boomer generation begins using Medicare. PMID:25080418

  15. Glacier recession in Iceland and Austria

    NASA Technical Reports Server (NTRS)

    Hall, Dorothy K.; Williams, Richard S., Jr.; Bayr, Klaus J.

    1992-01-01

    It has been possible to measure glacier recession on the basis of Landsat data, in conjunction with comparisons of the magnitude of recession of a glacier margin with in situ measurements at fixed points along the same margin. Attention is presently given to the cases of Vatnajokull ice cap, in Iceland, and the Pasterze Glacier, in Austria, on the basis of satellite data from 1973-1987 and 1984-1990, respectively. Indications of a trend toward negative mass balance are noted. Nevertheless, while most of the world's small glaciers have been receding, some are advancing either due to local climate or the tidewater glacier cycle.

  16. Autosomal recessive osteopetrosis in Arab children.

    PubMed

    Abdel-Al, Y K; Shabani, I S; Lubani, M M; al-Ghawabi, M A; Ibrahim, M D; al-Mohtaseb, S; Duodin, K I

    1994-01-01

    Nineteen Arab children including six boys and 13 girls in ten sibships were diagnosed as having osteopetrosis over a 5-year period in various hospitals in Kuwait. Eighteen patients had an isolated autosomal recessive form and one had autosomal recessive osteopetrosis associated with renal tubular acidosis. The mean age of diagnosis was 24 months. Parental consanguinity was high amongst them (68%). Anaemia, hepatosplenomegaly, failure to thrive, recurrent infections and neurological manifestations were common. Associated congenital abnormalities were found in 26%. Deafness, hydrocephalus and dental caries were relatively less common. A high mortality (37%) owing to infection was noted. The medical management and recommendations for patient care are discussed briefly. PMID:7516136

  17. Glacier recession in Iceland and Austria

    SciTech Connect

    Hall, D.K.; Williams, R.S. Jr.; Bayr, K.J. USGS, Reston, VA Keene State College, NH )

    1992-03-01

    It has been possible to measure glacier recession on the basis of Landsat data, in conjunction with comparisons of the magnitude of recession of a glacier margin with in situ measurements at fixed points along the same margin. Attention is presently given to the cases of Vatnajokull ice cap, in Iceland, and the Pasterze Glacier, in Austria, on the basis of satellite data from 1973-1987 and 1984-1990, respectively. Indications of a trend toward negative mass balance are noted. Nevertheless, while most of the world's small glaciers have been receding, some are advancing either due to local climate or the tidewater glacier cycle. 21 refs.

  18. Nevada, the Great Recession, and Education

    ERIC Educational Resources Information Center

    Verstegen, Deborah A.

    2013-01-01

    The impact of the Great Recession and its aftermath has been devastating in Nevada, especially for public education. This article discusses the budget shortfalls and the impact of the economic crisis in Nevada using case study methodology. It provides a review of documents, including Governor Gibbon's proposals for the public K-12 education system…

  19. The Global Picture. Recession to Recovery

    ERIC Educational Resources Information Center

    Universities UK, 2010

    2010-01-01

    The objectives of this study were to: (1) document government and HE (higher education) sector responses to the recession within a select number of key countries which compete with the UK; and (2) compare these responses and analyse them by theme to draw out any common patterns. The focus of the work was to find, where possible, an evidence base…

  20. Reclaiming Recess: Learning the Language of Persuasion

    ERIC Educational Resources Information Center

    Gebhard, Meg; Harman, Ruth; Seger, Wendy

    2007-01-01

    Using a case study approach, the authors describe how a teacher used the tools of systemic functional linguistics (SFL) to teach her fifth grade English Language Learners how to use academic language to challenge school policies regarding recess. In reflecting on these data, we discuss the potential of SFL to support teachers in responding to…

  1. Testing Faces Ups and Downs Amid Recession

    ERIC Educational Resources Information Center

    Sawchuk, Stephen

    2009-01-01

    As the recession crimps education budgets, states are beginning to pare the number of standardized tests they give, particularly those that no longer factor into state or federal accountability decisions. At the district level, though, it's a different story. Despite pressure not to cut staffing and programs, many districts are preserving local…

  2. Weathering the Recession in College Health

    ERIC Educational Resources Information Center

    Christmas, William A.

    2010-01-01

    The current global recession has increased personal stress levels throughout our society. With dwindling resources, institutions of higher learning are especially prone to budgetary cutbacks during such periods. Based on 22 years of experience as a health service director, the author offers some personal insights in the hope that they will help…

  3. Gender Differences during Recess in Elementary Schools.

    ERIC Educational Resources Information Center

    Twarek, Linda S.; George, Halley S.

    A study examined the differences in what boys and girls choose, or are free to choose, to do on the playground during recess. Given the apparent problem that boys dominate the playground area, leaving girls on the perimeter, it was hypothesized that girls engage in passive, non-competitive, small group activities, whereas boys engage in…

  4. Weathering the Recession in College Health

    ERIC Educational Resources Information Center

    Christmas, William A.

    2010-01-01

    The current global recession has increased personal stress levels throughout our society. With dwindling resources, institutions of higher learning are especially prone to budgetary cutbacks during such periods. Based on 22 years of experience as a health service director, the author offers some personal insights in the hope that they will help

  5. Measuring Fluctuating Pressures With Recessed Gauges

    NASA Technical Reports Server (NTRS)

    Parrott, Tony L.; Jones, Michael G.

    1993-01-01

    Report discusses use of pressure gauges mounted in recesses in interior wall of model scramjet engine. Consists of brief memorandum plus excerpts from NASA Technical Paper 3189, "Unsteady Pressure Loads In A Generic High-Speed Engine Model." Focuses mainly on factors affecting accuracy of gauge readings.

  6. Classification of left ventricular hypertrophies (LVH) based on discriminant analysis of time activity curve of equilibrium gated studies

    SciTech Connect

    Sychra, J.; Pavel, D.; Briandet, P.; Virupannavar, S.; Kondos, G.; Rich, S.; Shanes, J.; Olea, E.; Pietras, R.

    1985-05-01

    The authors have previously shown that LVH can be separated from normals by using parameters which characterize the early filling period, but the number of cases approaching the borderline zone is still significant and no separation between etiologies of LVH was possible. The use of discriminant analysis (DA) of multiple parameters (PAR) characterizing the whole time activity curve (TAC) is tested. 13 normals (N), 53 LVH patients (P) with EF > 55%, subdivided in 3 subgroups (SG): 14 IHSS; 13 hypertension or aortic stenosis; 26 LVH of unknown etiology. The Wilk's lambda and Rao's V test indicate significantly better separation power for DA than for the best pair or single diastolic PAR previously used. The ''leave-one-out'' test (designed to evaluate the capability to correctly classify new cases) showed that for DA with 5 FTS only (S) decreased slightly. When the same procedure was applied to the best pair of old PAR, (S) and (Sp) decreased significantly. This indicates the advantage of DA. The 3-class DA was able to separate the 3 SG within LVH in 86, 100 and 77% of cases respectively. In conclusion DA of multiple TAC PAR enables not only excellent separation of LVH cases but also a very good separation of etiologic subgroups.

  7. Validation of Kepler's Multiple Planet Candidates. III. Light Curve Analysis and Announcement of Hundreds of New Multi-planet Systems

    NASA Astrophysics Data System (ADS)

    Rowe, Jason F.; Bryson, Stephen T.; Marcy, Geoffrey W.; Lissauer, Jack J.; Jontof-Hutter, Daniel; Mullally, Fergal; Gilliland, Ronald L.; Issacson, Howard; Ford, Eric; Howell, Steve B.; Borucki, William J.; Haas, Michael; Huber, Daniel; Steffen, Jason H.; Thompson, Susan E.; Quintana, Elisa; Barclay, Thomas; Still, Martin; Fortney, Jonathan; Gautier, T. N., III; Hunter, Roger; Caldwell, Douglas A.; Ciardi, David R.; Devore, Edna; Cochran, William; Jenkins, Jon; Agol, Eric; Carter, Joshua A.; Geary, John

    2014-03-01

    The Kepler mission has discovered more than 2500 exoplanet candidates in the first two years of spacecraft data, with approximately 40% of those in candidate multi-planet systems. The high rate of multiplicity combined with the low rate of identified false positives indicates that the multiplanet systems contain very few false positive signals due to other systems not gravitationally bound to the target star. False positives in the multi-planet systems are identified and removed, leaving behind a residual population of candidate multi-planet transiting systems expected to have a false positive rate less than 1%. We present a sample of 340 planetary systems that contain 851 planets that are validated to substantially better than the 99% confidence level; the vast majority of these have not been previously verified as planets. We expect ~two unidentified false positives making our sample of planet very reliable. We present fundamental planetary properties of our sample based on a comprehensive analysis of Kepler light curves, ground-based spectroscopy, and high-resolution imaging. Since we do not require spectroscopy or high-resolution imaging for validation, some of our derived parameters for a planetary system may be systematically incorrect due to dilution from light due to additional stars in the photometric aperture. Nonetheless, our result nearly doubles the number verified exoplanets.

  8. Global Fit Analysis of Glucose Binding Curves Reveals a Minimal Model for Kinetic Cooperativity in Human Glucokinase

    PubMed Central

    Larion, Mioara; Miller, Brian G.

    2011-01-01

    Human pancreatic glucokinase is a monomeric enzyme that displays kinetic cooperativity, a feature that facilitates enzyme-mediated regulation of blood glucose levels in the body. Two theoretical models have been proposed to describe the non-Michaelis-Menten behavior of human glucokinase. The mnemonic mechanism postulates the existence of one thermodynamically favored enzyme conformation in the absence of glucose, whereas the ligand-induced slow transition model (LIST) requires a pre-existing equilibrium between two enzyme species that interconvert with a rate constant slower than turnover. To investigate whether either of these mechanisms is sufficient to describe glucokinase cooperativity, a transient state kinetic analysis of glucose binding to the enzyme was undertaken. A complex, time-dependent change in enzyme intrinsic fluorescence was observed upon exposure to glucose, which is best described by an analytical solution comprised of the sum of four exponential terms. Transient state glucose binding experiments conducted in the presence of increasing glycerol concentrations demonstrate that three of the observed rate constants decrease with increasing viscosity. Global fit analyses of experimental glucose binding curves do not support the glucose binding component of the mnemonic mechanism, the simplified LIST mechanism or a mechanism that includes three unliganded enzyme species. Instead, our experimental data are consistent with a LIST kinetic model that includes two additional glucose-bound binary complexes. The kinetic model presented herein suggests that glucokinase samples multiple conformations in the absence of ligand and that this conformational heterogeneity persists even after the enzyme associates with glucose. PMID:20828143

  9. Validation of Kepler's multiple planet candidates. III. Light curve analysis and announcement of hundreds of new multi-planet systems

    SciTech Connect

    Rowe, Jason F.; Bryson, Stephen T.; Lissauer, Jack J.; Jontof-Hutter, Daniel; Mullally, Fergal; Howell, Steve B.; Borucki, William J.; Haas, Michael; Huber, Daniel; Thompson, Susan E.; Quintana, Elisa; Barclay, Thomas; Still, Martin; Marcy, Geoffrey W.; Issacson, Howard; Gilliland, Ronald L.; Ford, Eric; Steffen, Jason H.; Gautier, T. N. III; and others

    2014-03-20

    The Kepler mission has discovered more than 2500 exoplanet candidates in the first two years of spacecraft data, with approximately 40% of those in candidate multi-planet systems. The high rate of multiplicity combined with the low rate of identified false positives indicates that the multiplanet systems contain very few false positive signals due to other systems not gravitationally bound to the target star. False positives in the multi-planet systems are identified and removed, leaving behind a residual population of candidate multi-planet transiting systems expected to have a false positive rate less than 1%. We present a sample of 340 planetary systems that contain 851 planets that are validated to substantially better than the 99% confidence level; the vast majority of these have not been previously verified as planets. We expect ∼two unidentified false positives making our sample of planet very reliable. We present fundamental planetary properties of our sample based on a comprehensive analysis of Kepler light curves, ground-based spectroscopy, and high-resolution imaging. Since we do not require spectroscopy or high-resolution imaging for validation, some of our derived parameters for a planetary system may be systematically incorrect due to dilution from light due to additional stars in the photometric aperture. Nonetheless, our result nearly doubles the number verified exoplanets.

  10. Pulse wave analysis in a 180-degree curved artery model: Implications under physiological and non-physiological inflows

    NASA Astrophysics Data System (ADS)

    Bulusu, Kartik V.; Plesniak, Michael W.

    2013-11-01

    Systolic and diastolic blood pressures, pulse pressures, and left ventricular hypertrophy contribute to cardiovascular risks. Increase of arterial stiffness due to aging and hypertension is an important factor in cardiovascular, chronic kidney and end-stage-renal-diseases. Pulse wave analysis (PWA) based on arterial pressure wave characteristics, is well established in clinical practice for evaluation of arterial distensibility and hypertension. The objective of our exploratory study in a rigid 180-degree curved artery model was to evaluate arterial pressure waveforms. Bend upstream conditions were measured using a two-component, two-dimensional, particle image velocimeter (2C-2D PIV). An ultrasonic transit-time flow meter and a catheter with a MEMS-based solid state pressure sensor, capable of measuring up to 20 harmonics of the observed pressure waveform, monitored flow conditions downstream of the bend. Our novel continuous wavelet transform algorithm (PIVlet 1.2), in addition to detecting coherent secondary flow structures is used to evaluate arterial pulse wave characteristics subjected to physiological and non-physiological inflows. Results of this study will elucidate the utility of wavelet transforms in arterial function evaluation and pulse wave speed. Supported by NSF Grant No. CBET- 0828903 and GW Center for Biomimetics and Bioinspired Engineering.

  11. Analytical derivation of the flood frequency curve through partial duration series analysis and a probabilistic representation of the runoff coefficient

    NASA Astrophysics Data System (ADS)

    Franchini, Marco; Galeati, Giorgio; Lolli, Marco

    2005-03-01

    The authors propose a procedure for estimating the discharge with an assigned return period based on a probabilistic formulation of the rational formula referred to a generic flood event. In this manner it is possible to represent the natural variability in the runoff coefficient and at the same time to relate rainfall depths to the corresponding flood events. The link between the probability distributions of the annual maximum rainfalls and floods and the frequency of the corresponding events in partial duration series is established through relations deriving from the assumption of Poissonian occurrences of the relative events over the year. The proposed procedure makes it possible to display the effect of the first and second moments of the random variable 'runoff coefficient' on the shape of the flood frequency curve. In particular, it may be shown analytically that the second moment of the probability distribution of the runoff coefficient controls the third moment of the distribution of annual maximum peak discharges and hence its curvature. The procedure is applied to several basins of the Romagna-Marche region (Italy), for which the results of a regional analysis conducted using the index method were already available, both in relation to annual maximum rainfall depths and peak discharges. A comparison of the results obtained by the two different procedures provides a basis for advancing some considerations regarding the potential of the proposed procedure and highlights aspects, which warrant further investigation.

  12. Self-modeling curve resolution (SMCR) analysis of near-infrared (NIR) imaging data of pharmaceutical tablets.

    PubMed

    Awa, Kimie; Okumura, Takehiro; Shinzawa, Hideyuki; Otsuka, Makoto; Ozaki, Yukihiro

    2008-06-30

    The idea of quality by design (QbD) has been proposed in pharmaceutical field. QbD is a systematic approach to control the product performance based on the scientific understanding of the product quality and its manufacturing process. In the present study, near-infrared (NIR) imaging is utilized as a tool to achieve this concept. A practical use of a chemometrics technique called self-modeling curve resolution (SMCR) is demonstrated with NIR imaging analysis of pharmaceutical tablets containing two ingredients, a soluble active ingredient, pentoxifylline (PTX), and an insoluble excipient, palmitic acid. Concentration profiles obtained by SMCR reveal that the homogenous distribution of chemical ingredients strongly depends on the grinding time and that its process plays a central role in quantitative control, say sustained-release of PTX. In addition, pure component spectra by SMCR indicate a sequential change of specific NIR peak intensities following the increase of the grinding time. The spectra change shows a molecular structure change related to its crystallinity during grinding process. Accordingly, this study clearly demonstrates that NIR imaging combined with SMCR can be a powerful tool to reveal chemical or physical mechanism induced by the manufacturing process of pharmaceutical products and that it may be a solid solution for QbD of pharmaceutical products. PMID:18539178

  13. Determination of sulphate in water and biodiesel samples by a sequential injection analysis--multivariate curve resolution method.

    PubMed

    del Río, Vanessa; Larrechi, M Soledad; Callao, M Pilar

    2010-08-31

    A spectrophotometric sequential injection analysis (SIA-DAD) method linked to multivariate curve resolution-alternating least squares (MCR-ALS) has been developed for sulphate determination. This method involves the reaction, inside the tubes of the SIA system, of sulphate with barium-dimethylsulphonazo (III) complex, Ba-DMSA (III), displacing Ba(2+) from the complex and forming DMSA (III). When the reaction products reach the detector a data matrix is obtained, which allows a second-order calibration to be developed. The experimental conditions (concentration and sample and reagent volumes) to obtain the highest sensitivity have been chosen applying a 2(4-1) fractional factorial design. The proposed sequential flow procedure permits up to 15 mg SO(4)(2-) L(-1) to be determined with a limit of detection of 1.42 mg L(-1) and it is able to monitor sulphate in samples at a frequency of 15 samples per hour. The method was applied to determine sulphate in natural and residual waters and in biodiesel. The reliability of the method was established for water samples by parallel determination using a standard turbidimetric method for sulphate in natural and residual water samples with results within statistical variation. For biodiesel samples, the method was validated comparing the concentration of some spiked samples with the expected concentration using a test-t. PMID:20800738

  14. Observations and analysis of the light curve of the WUMa system AE Phoenicis during 1975-1977

    NASA Astrophysics Data System (ADS)

    Walter, K.; Duerbeck, H. W.

    1988-01-01

    Photometric observations of the WUMa system AEPhe obtained at La Silla in the years 1975-1977 are presented. The UBV light curves display marked variations with time. The two periods, 55d and 95d, found by Walter (1982) from observations in 1978, and interpreted as the precessional periods of the components, could be confirmed and refined to 55d.9 and 99d.6 It is shown that the variations of the light curve are caused by bright as well as by dark areas. Large light curve distortions were found in 1976.

  15. On the transition of base flow recession from early stage to late stage

    NASA Astrophysics Data System (ADS)

    Ghosh, Debapi K.; Wang, Dingbao; Zhu, Tingju

    2016-02-01

    This paper is focused on the transition of base flow recession from early stage to late stage. The volume flow rate that takes place when such a transition occurs is identified for each of the twenty-three recession events observed at the Panola Mountain Research Watershed (PMRW) in Georgia, USA, using a newly developed cumulative regression analysis method. Meanwhile, the flow at the watershed outlet, which was recorded when the discharge at the perennial stream head diminishes to zero, is identified for each recession event. As evidenced by a correlation coefficient of 0.90, these two characteristic flows are found to be highly correlated, suggesting a fundamental linkage between the transition of base flow recession from early stage to late stage and the drying up of ephemeral streams. During the early stage, the contraction of ephemeral streams largely controls the recession behavior, whereas in the late stage when perennial streams dominate the flowing streams, the contraction of flowing streams is minimal and groundwater hydraulics governs the recession behavior.

  16. [Analysis of recessive sex-linked lethal mutations in genotypically different strains of Drosophila melanogaster MS and w, exposed in the 5-kilometer zone of the accident at the Chernobyl nuclear reactor].

    PubMed

    Aslanian, M M; Kim, A I; Magomedova, M A; Fatkulbaianova, N L

    1994-09-01

    The frequency of induced and spontaneous recessive sex-linked lethal mutations (RSLLM) in Drosophila melanogaster strains w and ms was estimated after their chronic irradiation in the five-kilometer zone of the Chernobyl' meltdown. The mutagenic effect of relatively low radiation doses was analyzed. In an experiment conducted in 1990, a significant increase in the RSLLM frequency was recorded, while, in 1991, no significant difference between the experiment and control was found. PMID:8001804

  17. Two Aspects of the Simplex Model: Goodness of Fit to Linear Growth Curve Structures and the Analysis of Mean Trends.

    ERIC Educational Resources Information Center

    Mandys, Frantisek; Dolan, Conor V.; Molenaar, Peter C. M.

    1994-01-01

    Studied the conditions under which the quasi-Markov simplex model fits a linear growth curve covariance structure and determined when the model is rejected. Presents a quasi-Markov simplex model with structured means and gives an example. (SLD)

  18. A Latent Growth Curve Analysis of the Structure of Aggression, Drug Use, and Delinquent Behaviors and their Interrelations over Time in Urban and Rural Adolescents

    ERIC Educational Resources Information Center

    Farrell, Albert D.; Sullivan, Terri N.; Esposito, Layla E.; Meyer, Aleta L.; Valois, Robert F.

    2005-01-01

    Latent growth curve analysis was used to examine the structure and interrelations among aggression, drug use, and delinquent behavior during early adolescence. Five waves of data were collected from 667 students at three urban middle schools serving a predominantly African American population, and from a more ethnically diverse sample of 950

  19. Genetics Home Reference: autosomal recessive cerebellar ataxia type 1

    MedlinePlus

    ... autosomal recessive 8 Johns Hopkins Medicine Department of Neurology and Neurosurgery: What is Ataxia? MedlinePlus Encyclopedia: Dysarthria-- ... autosomal recessive 8 Johns Hopkins Medicine Department of Neurology and Neurosurgery: What is Ataxia? Kennedy Krieger Institute: ...

  20. Measuring the elastic properties of living cells through the analysis of current-displacement curves in scanning ion conductance microscopy.

    PubMed

    Pellegrino, Mario; Pellegrini, Monica; Orsini, Paolo; Tognoni, Elisabetta; Ascoli, Cesare; Baschieri, Paolo; Dinelli, Franco

    2012-09-01

    Knowledge of mechanical properties of living cells is essential to understand their physiological and pathological conditions. To measure local cellular elasticity, scanning probe techniques have been increasingly employed. In particular, non-contact scanning ion conductance microscopy (SICM) has been used for this purpose; thanks to the application of a hydrostatic pressure via the SICM pipette. However, the measurement of sample deformations induced by weak pressures at a short distance has not yet been carried out. A direct quantification of the applied pressure has not been also achieved up to now. These two issues are highly relevant, especially when one addresses the investigation of thin cell regions. In this paper, we present an approach to solve these problems based on the use of a setup integrating SICM, atomic force microscopy, and optical microscopy. In particular, we describe how we can directly image the pipette aperture in situ. Additionally, we can measure the force induced by a constant hydrostatic pressure applied via the pipette over the entire probe-sample distance range from a remote point to contact. Then, we demonstrate that the sample deformation induced by an external pressure applied to the pipette can be indirectly and reliably evaluated from the analysis of the current-displacement curves. This method allows us to measure the linear relationship between indentation and applied pressure on uniformly deformable elastomers of known Young's modulus. Finally, we apply the method to murine fibroblasts and we show that it is sensitive to local and temporally induced variations of the cell surface elasticity. PMID:22744227

  1. High-throughput avian molecular sexing by SYBR green-based real-time PCR combined with melting curve analysis

    PubMed Central

    Chang, Hsueh-Wei; Cheng, Chun-An; Gu, De-Leung; Chang, Chia-Che; Su, San-Hua; Wen, Cheng-Hao; Chou, Yii-Cheng; Chou, Ta-Ching; Yao, Cheng-Te; Tsai, Chi-Li; Cheng, Chien-Chung

    2008-01-01

    Background Combination of CHD (chromo-helicase-DNA binding protein)-specific polymerase chain reaction (PCR) with electrophoresis (PCR/electrophoresis) is the most common avian molecular sexing technique but it is lab-intensive and gel-required. Gender determination often fails when the difference in length between the PCR products of CHD-Z and CHD-W genes is too short to be resolved. Results Here, we are the first to introduce a PCR-melting curve analysis (PCR/MCA) to identify the gender of birds by genomic DNA, which is gel-free, quick, and inexpensive. Spilornis cheela hoya (S. c. hoya) and Pycnonotus sinensis (P. sinensis) were used to illustrate this novel molecular sexing technique. The difference in the length of CHD genes in S. c. hoya and P. sinensis is 13-, and 52-bp, respectively. Using Griffiths' P2/P8 primers, molecular sexing failed both in PCR/electrophoresis of S. c. hoya and in PCR/MCA of S. c. hoya and P. sinensis. In contrast, we redesigned sex-specific primers to yield 185- and 112-bp PCR products for the CHD-Z and CHD-W genes of S. c. hoya, respectively, using PCR/MCA. Using this specific primer set, at least 13 samples of S. c. hoya were examined simultaneously and the Tm peaks of CHD-Z and CHD-W PCR products were distinguished. Conclusion In this study, we introduced a high-throughput avian molecular sexing technique and successfully applied it to two species. This new method holds a great potential for use in high throughput sexing of other avian species, as well. PMID:18269737

  2. Understanding High Recession Rates of Carbon Ablators Seen in Shear Tests in an Arc Jet

    NASA Technical Reports Server (NTRS)

    Driver, David M.; Olson, Michael W.; Barnhardt, Michael D.; MacLean, Matthew

    2010-01-01

    High rates of recession in arc jet shear tests of Phenolic Impregnated Carbon Ablator (PICA) inspired a series of tests and analysis on FiberForm (a carbon preform used in the fabrication of PICA). Arc jet tests were performed on FiberForm in both air and pure nitrogen for stagnation and shear configurations. The nitrogen tests showed little or no recession, while the air tests of FiberForm showed recession rates similar to that of PICA (when adjusted for the difference in density). While mechanical erosion can not be ruled out, this is the first step in doing so. Analysis using a carbon oxidation boundary condition within DPLR was used to predict the recession rate of FiberForm. The analysis indicates that much of the anomalous recession behavior seen in shear tests may simply be an artifact of the non-flight like test configuration (copper upstream of the test article) a result of dissimilar enthalpy and oxygen concentration profiles on the copper. Shape change effects were also investigated and shown to be relatively small.

  3. Rapid detection of isoniazid resistance in Mycobacterium tuberculosis isolates by use of real-time-PCR-based melting curve analysis.

    PubMed

    Hu, Siyu; Li, Guoli; Li, Hui; Liu, Xiaoli; Niu, Jianjun; Quan, Shengmao; Wang, Feng; Wen, Huixin; Xu, Ye; Li, Qingge

    2014-05-01

    The MeltPro TB/INH assay, recently approved by the Chinese Food and Drug Administration, is a closed-tube, dual-color, melting curve analysis-based, real-time PCR test specially designed to detect 30 isoniazid (INH) resistance mutations in katG position 315 (katG 315), the inhA promoter (positions -17 to -8), inhA position 94, and the ahpC promoter (positions -44 to -30 and -15 to 3) of Mycobacterium tuberculosis. Here we evaluated both the analytical performance and clinical performance of this assay. Analytical studies with corresponding panels demonstrated that the accuracy for detection of different mutation types (10 wild-type samples and 12 mutant type samples), the limit of detection (2×10(3) to 2×10(4) bacilli/ml), reproducibility (standard deviation [SD], <0.4°C), and the lowest heteroresistance level (40%) all met the parameters preset by the kit. The assay could be run on five types of real-time PCR machines, with the shortest running time (105 min) obtained with the LightCycler 480 II. Clinical studies enrolled 1,096 clinical isolates collected from three geographically different tuberculosis centers, including 437 INH-resistant isolates and 659 INH-susceptible isolates characterized by traditional drug susceptibility testing on Löwenstein-Jensen solid medium. The clinical sensitivity and specificity of the MeltPro TB/INH assay were 90.8% and 96.4%, respectively. DNA sequencing analysis showed that, except for the 5 mutants outside the detection range of the MeltPro assay, a concordance rate between the two methods of 99.1% (457/461) was obtained. Among the 26 mutation types detected, katG S315T (AGC→ACC), inhA -15C→T, katG S315N (AGC→AAC), and ahpC promoter -10C→T accounted for more than 90%. Overall, the MeltPro TB/INH assay represents a reliable and rapid tool for the detection of INH resistance in clinical isolates. PMID:24599986

  4. Cutting Symmetrical Recesses In Soft Ceramic Tiles

    NASA Technical Reports Server (NTRS)

    Nesotas, Tony C.; Tyler, Brent

    1989-01-01

    Simple tool cuts hemispherical recesses in soft ceramic tiles. Designed to expose wires of thermocouples embedded in tiles without damaging leads. Creates neat, precise holes around wires. End mill includes axial hole to accommodate thermocouple wires embedded in material to be cut. Wires pass into hole without being bent or broken. Dimensions in inches. Used in place of such tools as dental picks, tweezers, spatulas, and putty knives.

  5. Recessive mutations in CAKUT and VACTERL association.

    PubMed

    Westland, Rik; Sanna-Cherchi, Simone

    2014-06-01

    Understanding the complex genetic makeup underlying congenital anomalies of the kidney and urinary tract (CAKUT) is of primary importance to improve diagnosis, stratify risk for later-onset complications, and develop therapeutic strategies. Saisawat et al. used homozygosity mapping coupled with next-generation sequencing to identify recessive mutations in TRAP1 in families with isolated CAKUT and with VACTERL association. This study points to a novel player in kidney development, possibly affecting apoptosis and endoplasmic reticulum stress signaling. PMID:24875543

  6. Recession. When good times turn bad.

    PubMed

    Cowper, Andy

    2008-12-01

    The 1973-74 recession meant the government was forced to cut public spending and a hospital building programme was curtailed. In the 1990s there was "desperation" in the health service at being under-resourced. Managers today are advised to prepare now for lower resources, although improved financial management should mean the NHS is better able to cope than in previous years. PMID:19156941

  7. Photogrammetric recession measurements of an ablating surface

    NASA Technical Reports Server (NTRS)

    Schairer, Edward T. (Inventor); Heineck, James T. (Inventor)

    2012-01-01

    An instrument and method for measuring the time history of recession of an ablating surface of a test article during testing in a high enthalpy thermal test facility, such as an arcjet. The method advances prior art by providing time-history data over the full ablating surface without targets and without any modifications to the test article. The method is non-intrusive, simple to implement, requires no external light source, and does not interfere with normal operations of the arcjet facility.

  8. Semiconductor devices having a recessed electrode structure

    DOEpatents

    Palacios, Tomas Apostol; Lu, Bin; Matioli, Elison de Nazareth

    2015-05-26

    An electrode structure is described in which conductive regions are recessed into a semiconductor region. Trenches may be formed in a semiconductor region, such that conductive regions can be formed in the trenches. The electrode structure may be used in semiconductor devices such as field effect transistors or diodes. Nitride-based power semiconductor devices are described including such an electrode structure, which can reduce leakage current and otherwise improve performance.

  9. Polycrystalline diamond cutting element with mating recess

    SciTech Connect

    Keith, C.W.

    1990-03-27

    This patent describes a polycrystalline diamond cutting element with mating recess for use on a cutting tool. It comprises: a mounting body having a leading face and a trailing face and a relatively thin layer of super hard material carried on the leading face of the mounting body and defining a cutting face for the cutting element. Also described is a bit for use in drilling earthen formations.

  10. Synthetic light-curve analysis of the very short period binaries TY Bootis, AD Cancri, and V523 Cassiopeiae

    SciTech Connect

    Samec, R.G.; Van Hamme, W.; Bookmyer, B.B. Clemson Univ., SC South Carolina Univ., Conway Florida International Univ., Miami )

    1989-12-01

    New photometric observations of TY Boo, AD Cnc, and V523 Cas are subjected to synthetic light-curve analyses using the Wilson-Devinney code. Solutions for each of the systems, and the several competing theories of contact binary structure are discussed in light of the results. Both AD Cnc and V523 Cas are modeled with subluminous regions, and the resulting starspot parameters are reported. A simultaneous solution of the B, V light curves and the radial-velocity curves of V523 Cas is presented. Spectroscopic and photometric mass ratios were found to be discordant for both TY Boo and V523 Cas. However, recent spectroscopic work by Groissman seems to remove the discordancy for TY Boo. Absolute parameters are derived for V523 Cas. 43 refs.

  11. The eclipsing binary star V380 Gem: First V and Rc light curve analysis and estimation of its absolute elements

    NASA Astrophysics Data System (ADS)

    Barani, C.; Martignoni, M.; Acerbi, F.

    2013-10-01

    We obtained complete V and Rc light curves of the eclipsing binary V380 Gem in 2012. With our data we were able to determine six new times of minimum light and refine the orbital period of the system to 0.3366088 days. The 2003 version of the Wilson-Devinney code was used to analyze the light curves in the V and Rc bands simultaneously. It is shown that V380 Gem may be classified as an W-type W Ursae Majoris system with a high mass ratio q = 1.45, a degree of contact f = 10.6% the same temperature for both the components (?T = 10 K) and an orbital inclination of i = 81.5. Our observations show symmetric light curves in all passbands with brightness in both maxima at the same level. The absolute dimensions of V380 Gem are estimated and its dynamical evolution is inferred.

  12. X-ray photoemission analysis of clean and carbon monoxide-chemisorbed platinum(111) stepped surfaces using a curved crystal.

    PubMed

    Walter, Andrew L; Schiller, Frederik; Corso, Martina; Merte, Lindsay R; Bertram, Florian; Lobo-Checa, Jorge; Shipilin, Mikhail; Gustafson, Johan; Lundgren, Edvin; Brión-Ríos, Anto N X; Cabrera-Sanfelix, Pepa; Sánchez-Portal, Daniel; Ortega, J Enrique

    2015-01-01

    Surface chemistry and catalysis studies could significantly gain from the systematic variation of surface active sites, tested under the very same conditions. Curved crystals are excellent platforms to perform such systematics, which may in turn allow to better resolve fundamental properties and reveal new phenomena. This is demonstrated here for the carbon monoxide/platinum system. We curve a platinum crystal around the high-symmetry (111) direction and carry out photoemission scans on top. This renders the spatial core-level imaging of carbon monoxide adsorbed on a 'tunable' vicinal surface, allowing a straightforward visualization of the rich chemisorption phenomenology at steps and terraces. Through such photoemission images we probe a characteristic elastic strain variation at stepped surfaces, and unveil subtle stress-release effects on clean and covered vicinal surfaces. These results offer the prospect of applying the curved surface approach to rationally investigate the chemical activity of surfaces under real pressure conditions. PMID:26561388

  13. X-ray photoemission analysis of clean and carbon monoxide-chemisorbed platinum(111) stepped surfaces using a curved crystal

    PubMed Central

    Walter, Andrew L.; Schiller, Frederik; Corso, Martina; Merte, Lindsay R.; Bertram, Florian; Lobo-Checa, Jorge; Shipilin, Mikhail; Gustafson, Johan; Lundgren, Edvin; Brión-Ríos, Anto´n X.; Cabrera-Sanfelix, Pepa; Sánchez-Portal, Daniel; Ortega, J. Enrique

    2015-01-01

    Surface chemistry and catalysis studies could significantly gain from the systematic variation of surface active sites, tested under the very same conditions. Curved crystals are excellent platforms to perform such systematics, which may in turn allow to better resolve fundamental properties and reveal new phenomena. This is demonstrated here for the carbon monoxide/platinum system. We curve a platinum crystal around the high-symmetry (111) direction and carry out photoemission scans on top. This renders the spatial core-level imaging of carbon monoxide adsorbed on a ‘tunable' vicinal surface, allowing a straightforward visualization of the rich chemisorption phenomenology at steps and terraces. Through such photoemission images we probe a characteristic elastic strain variation at stepped surfaces, and unveil subtle stress-release effects on clean and covered vicinal surfaces. These results offer the prospect of applying the curved surface approach to rationally investigate the chemical activity of surfaces under real pressure conditions. PMID:26561388

  14. Multilayer theory for delamination analysis of a composite curved bar subjected to end forces and end moments

    NASA Technical Reports Server (NTRS)

    Ko, William L.; Jackson, Raymond H.

    1989-01-01

    A composite test specimen in the shape of a semicircular curved bar subjected to bending offers an excellent stress field for studying the open-mode delamination behavior of laminated composite materials. This is because the open-mode delamination nucleates at the midspan of the curved bar. The classical anisotropic elasticity theory was used to construct a multilayer theory for the calculations of the stress and deformation fields induced in the multilayered composite semicircular curved bar subjected to end forces and end moments. The radial location and intensity of the open-mode delamination stress were calculated and were compared with the results obtained from the anisotropic continuum theory and from the finite element method. The multilayer theory gave more accurate predictions of the location and the intensity of the open-mode delamination stress than those calculated from the anisotropic continuum theory.

  15. The Great Recession, unemployment and suicide

    PubMed Central

    Norström, Thor; Grönqvist, Hans

    2015-01-01

    Background How have suicide rates responded to the marked increase in unemployment spurred by the Great Recession? Our paper puts this issue into a wider perspective by assessing (1) whether the unemployment-suicide link is modified by the degree of unemployment protection, and (2) whether the effect on suicide of the present crisis differs from the effects of previous economic downturns. Methods We analysed the unemployment-suicide link using time-series data for 30 countries spanning the period 1960–2012. Separate fixed-effects models were estimated for each of five welfare state regimes with different levels of unemployment protection (Eastern, Southern, Anglo-Saxon, Bismarckian and Scandinavian). We included an interaction term to capture the possible excess effect of unemployment during the Great Recession. Results The largest unemployment increases occurred in the welfare state regimes with the least generous unemployment protection. The unemployment effect on male suicides was statistically significant in all welfare regimes, except the Scandinavian one. The effect on female suicides was significant only in the eastern European country group. There was a significant gradient in the effects, being stronger the less generous the unemployment protection. The interaction term capturing the possible excess effect of unemployment during the financial crisis was not significant. Conclusions Our findings suggest that the more generous the unemployment protection the weaker the detrimental impact on suicide of the increasing unemployment during the Great Recession. PMID:25339416

  16. Multi-institutional retrospective analysis of learning curves on dosimetry and operation time before and after introduction of intraoperatively built custom-linked seeds in prostate brachytherapy

    PubMed Central

    Ishiyama, Hiromichi; Satoh, Takefumi; Yorozu, Atsunori; Saito, Shiro; Kataoka, Masaaki; Hashine, Katsuyoshi; Nakamura, Ryuji; Tanji, Susumu; Masui, Koji; Okihara, Koji; Ohashi, Toshio; Momma, Tetsuo; Aoki, Manabu; Miki, Kenta; Kato, Masako; Morita, Masashi; Katayama, Norihisa; Nasu, Yasutomo; Kawanaka, Takashi; Fukumori, Tomoharu; Ito, Fumitaka; Shiroki, Ryoichi; Baba, Yuji; Inadome, Akito; Yoshioka, Yasuo; Takayama, Hitoshi; Hayakawa, Kazushige

    2016-01-01

    This multi-institutional retrospective analysis examined learning curves for dosimetric parameters and operation time after introduction of intraoperatively built custom-linked (IBCL) seeds. Data from consecutive patients treated with seed implantation before and after introduction of IBCL seeds (loose seed, n = 428; IBCL seed, n = 426) were collected from 13 centers. Dose–volume histogram parameters, operation times, and seed migration rates were compared before and after introduction of IBCL seeds. At the 1-month CT analysis, no significant differences were seen in dose to 90% of prostate volume between before and after IBCL seed introduction. No learning curve for dosimetry was seen. Prostate and rectal volume receiving at least 150% of prescription dose (V150 and RV150) were higher in the loose-seed group than in the IBCL-seed group. Operation time was extended by up to 10 min when IBCL seeds were used, although there was a short learning curve of about five patients. The percentage of patients with seed migration in the IBCL-seed group was one-tenth that in the loose-seed group. Our study revealed no dosimetric demerits, no learning curve for dosimetry, and a slightly extended operation time for IBCL seeds. A significant reduction in the rate of seed migration was identified in the IBCL-seed group. PMID:26494116

  17. Analysis of tipping-curve measurements performed at the DSS-13 beam-waveguide antenna at 32.0 and 8.45 GigaHertz

    NASA Technical Reports Server (NTRS)

    Morabito, D. D.; Skjerve, L.

    1995-01-01

    This article reports on the analysis of the Ka-band Antenna Performance Experiment tipping-curve data acquired at the DSS-13 research and development beam-waveguide (BWG) antenna. By measuring the operating system temperatures as the antenna is moved form zenith to low-elevation angles and fitting a model to the data, one can obtain information on how well the overall temperature model behaves at zenith and approximate the contribution due to the atmosphere. The atmospheric contribution estimated from the data can be expressed in the form of (1) atmospheric noise temperatures that can provide weather statistic information and be compared against those estimated from other methods and (2) the atmospheric loss factor used to refer efficiency measurements to zero atmosphere. This article reports on an analysis performed on a set of 68 8.4-GHz and 67 32-GHz tipping-curve data sets acquired between December 1993 and May 1995 and compares the results with those inferred from a surface model using input meteorological data and from water vapor radiometer (WVR) data. The general results are that, for a selected subset of tip curves, (1) the BWG tipping-curve atmospheric temperatures are in good agreement with those determined from WVR data (the average difference is 0.06 +/- 0.64 K at 32 GHz) and (2) the surface model average values are biased 3.6 K below those of the BWG and WVR at 32 GHz.

  18. Analytical approximations of discharge recessions for steeply sloping aquifers in alpine catchments

    NASA Astrophysics Data System (ADS)

    Pauritsch, Marcus; Birk, Steffen; Wagner, Thomas; Hergarten, Stefan; Winkler, Gerfried

    2015-11-01

    The validity and applicability of various methods to infer hydraulic properties of sloping aquifers in alpine settings using the power law relationship between the discharge recession and its first time derivative is explored. For this purpose, a synthetic spring catchment implemented in the numerical groundwater flow model MODFLOW as well as the example of a relict rock glacier in an alpine setting is examined. The various approaches are found to differ particularly in the late time domain, whereas most of them agree fairly well in the early time domain and at the transition point between the two time domains. As the early recession may be affected by uncertainties from inappropriate initial conditions, it is proposed to use the transition point for estimating aquifer thickness and transmissivity. Using only prolonged winter recessions in the analysis of the field data from the relict rock glacier yields estimates of aquifer thickness and hydraulic conductivity consistent with results from a geophysical survey and tracer tests, respectively. In the other seasons, the recession is frequently interrupted by minor recharge events, and using the lower envelope of the entire data is found to yield estimates that are too high in the given case. It is thus recommended to focus on the winter recession in the analysis of hydrograph data from alpine settings.

  19. Differences in the evolutionary history of disease genes affected by dominant or recessive mutations

    PubMed Central

    Furney, Simon J; Albà, M Mar; López-Bigas, Núria

    2006-01-01

    Background Global analyses of human disease genes by computational methods have yielded important advances in the understanding of human diseases. Generally these studies have treated the group of disease genes uniformly, thus ignoring the type of disease-causing mutations (dominant or recessive). In this report we present a comprehensive study of the evolutionary history of autosomal disease genes separated by mode of inheritance. Results We examine differences in protein and coding sequence conservation between dominant and recessive human disease genes. Our analysis shows that disease genes affected by dominant mutations are more conserved than those affected by recessive mutations. This could be a consequence of the fact that recessive mutations remain hidden from selection while heterozygous. Furthermore, we employ functional annotation analysis and investigations into disease severity to support this hypothesis. Conclusion This study elucidates important differences between dominantly- and recessively-acting disease genes in terms of protein and DNA sequence conservation, paralogy and essentiality. We propose that the division of disease genes by mode of inheritance will enhance both understanding of the disease process and prediction of candidate disease genes in the future. PMID:16817963

  20. A Unified Latent Curve, Latent State-Trait Analysis of the Developmental Trajectories and Correlates of Positive Orientation

    ERIC Educational Resources Information Center

    Alessandri, Guido; Caprara, Gian Vittorio; Tisak, John

    2012-01-01

    Literature documents that the judgments people hold about themselves, their life, and their future are important ingredients of their psychological functioning and well-being and are commonly related to each other. In this article, results from a longitudinal study (N = 298, 45% males) are presented. Using an integrative Latent Curve, Latent…

  1. Application of a tangent curve mathematical model for analysis of the mechanical behaviour of sunflower bulk seeds

    NASA Astrophysics Data System (ADS)

    Sigalingging, Riswanti; Herák, David; Kabutey, Abraham; Dajbych, Oldřich; Hrabě, Petr; Mizera, Čestmír

    2015-10-01

    This paper evaluate the use of a tangent curve mathematical model for representation of the mechanical behaviour of sunflower bulk seeds. Compression machine (Tempos Model 50, Czech Republic) and pressing vessel diameter 60 mm were used for the loading experiment. Varying forces between 50 and 130 kN and speeds ranging from 10, 50, and 100 mm min-1 were applied respectively on the bulk seeds with moisture content 12.37±0.38% w.b. The relationship between force and deformation curves of bulk seeds of pressing height 80 mm was described. The oil point strain was also determined from the different deformation values namely 30, 35, 40, and 45 mm at speed 10 mm min-1. Based on the results obtained, model coefficients were determined for fitting the experimental load and deformation curves. The validity of these coefficients were dependent on the bulk seeds of pressing height, vessel diameter, maximum force 110 kN, and speed 10 mm min-1, where optimal oil yield was observed. The oil point was detected at 45 mm deformation giving the strain value of 0.56 with the corresponding force 16.65±3.51 kN and energy 1.06±0.18 MJ m-3. At the force of 130 kN, a serration effect on the curves was indicated; hence, the compression process was ceased.

  2. First Precision Light Curve Analysis of the Neglected Extreme Mass Ratio Solar-type Binary HR Bootis

    NASA Astrophysics Data System (ADS)

    Samec, Ronald G.; Benkendorf, Barry; Dignan, James B.; Robb, Russell; Kring, James; Faulkner, Danny R.

    2015-04-01

    HR Bootis is a neglected binary that is found to be a solar-type (G2V) extreme mass ratio binary (EMRB). It was discovered by Hanley & Shapley in 1940. Surprisingly, little has been published in the intervening years. In 1999 it was characterized by a 0.31587 day orbital period. Since that time it has been observed by various observers who have determined ˜20 timings of minimum light over the past ˜15,000 orbits. Our observations in 2012 represent the first precision curves in the BVRcIc Johnson-Cousins wavelength bands. The light curves have rather low amplitudes, averaging some 0.5 magnitudes, yet they exhibit total eclipses, which is typical of the rare group of solar-type EMRBs. An improved linear ephemeris was computed along with a quadratic ephemeris showing a decaying orbit, which indicates magnetic breaking may be occurring. The light curve solution reveals that HR Boo is a contact system with a somewhat low 21% Roche-lobe fill-out but a mass ratio of q = 4.09 (0.2444), which defines it as an EMRB. Two spots, both hot, were allowed to iterate to fit the light curve asymmetries. Their radii are 32° and 16°. Both are high-latitude polar spots indicative of strong magnetic activity. The shallow contact yet nearly equal component temperatures makes it an unusual addition to this group.

  3. The Obsessive Compulsive Scale of the Child Behavior Checklist Predicts Obsessive-Compulsive Disorder: A Receiver Operating Characteristic Curve Analysis

    ERIC Educational Resources Information Center

    Hudziak, James J.; Althoff, Robert R.; Stanger, Catherine; van Beijsterveldt, C. E. M.; Nelson, Elliot C.; Hanna, Gregory L.; Boomsma, Dorret I.; Todd, Richard D.

    2006-01-01

    Background: The purpose of this study was to determine a score on the Obsessive Compulsive Scale (OCS) from the Child Behavior Checklist (CBCL) to screen for obsessive compulsive disorder (OCD) in children and to rigorously test the specificity and sensitivity of a single cutpoint. Methods: A receiver operating characteristic (ROC) curve analysis…

  4. Statistical methods for pavement performance curve building, historical analysis, data sampling and storage: Appendix D. Final report

    SciTech Connect

    1998-08-01

    The technical memorandum is intended to discuss the detailed procedure required for carrying out the statistical analyses of historical pavement condition data for building pavement performance curves. This chapter assumes the availability of the historical data in a spreadsheet format (Microsoft{trademark} Excel) that has been retrieved from the master (pavement management system) database.

  5. A Statistical Comparison of the Blossom Blight Forecasts of MARYBLYT and Cougarblight with Receiver Operating Characteristic Curve Analysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blossom blight forecasting is an important aspect of fire blight, caused by Erwinia amylovora, management for both apple and pear. A comparison of the forecast accuracy of two common fire blight forecasters, MARYBLYT and Cougarblight, was performed with receiver operating characteristic (ROC) curve ...

  6. Growth curve analysis of placental and fetal growth influenced by adjacent fetal sex status under crowded uterine conditions in pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intrauterine position and sex of adjacent fetuses in litter bearing species have been implicated in physiological and behavioral differences in males and females. Our objective was to establish growth curves for fetal and placental weight gain as influenced by sex status of flanking fetuses under cr...

  7. Large deformation analysis and synthesis of elastic closed-loop mechanism made of a certain spring wire described by free curves

    NASA Astrophysics Data System (ADS)

    Iwatsuki, Nobuyuki; Kosaki, Takashi

    2015-07-01

    Recently novel mechanisms with compact size and without many mechanical elements such as bearing are strongly required for medical devices such as surgical operation devices. This paper describes analysis and synthesis of elastic link mechanisms of a single spring beam which can be manufactured by NC coiling machines. These mechanisms are expected as disposable micro forceps. Smooth Curvature Model(SCM) with 3rd order Legendre polynomial curvature functions is applied to calculate large deformation of a curved cantilever beam by taking account of the balance between external and internal elastic forces and moments. SCM is then extended to analyze large deformation of a closed-loop curved elastic beam which is composed of multiple free curved beams. A closed-loop elastic link is divided into two free curved cantilever beams each of which is assumed as serially connected free curved cantilever beams described with SCM. The sets of coefficients of Legendre polynomials of SCM in all free curved cantilever beams are determined by taking account of the force and moment balance at connecting point where external input force is applied. The sets of coefficients of Legendre polynomials of a nonleaded closed-loop elastic link are optimized to design a link mechanism which can generate specified output motion due to input force applied at the assumed dividing point. For example, two planar micro grippers with a single pulling input force are analyzed and designed. The elastic deformation analyzed with proposed method agrees very well with that calculated with FEM. The designed micro gripper can generate the desired pinching motion. The proposed method can contribute to design compact and simple elastic mechanisms without high calculation costs.

  8. Effects of Tip Clearance and Casing Recess on Heat Transfer and Stage Efficiency in Axial Turbines

    NASA Technical Reports Server (NTRS)

    Ameri, A. A.; Steinthorsson, E.; Rigby, David L.

    1998-01-01

    Calculations were performed to assess the effect of the tip leakage flow on the rate of heat transfer to blade, blade tip and casing. The effect on exit angle and efficiency was also examined. Passage geometries with and without casing recess were considered. The geometry and the flow conditions of the GE-E 3 first stage turbine, which represents a modem gas turbine blade were used for the analysis. Clearance heights of 0%, 1%, 1.5% and 3% of the passage height were considered. For the two largest clearance heights considered, different recess depths were studied. There was an increase in the thermal load on all the heat transfer surfaces considered due to enlargement of the clearance gap. Introduction of recessed casing resulted in a drop in the rate of heat transfer on the pressure side but the picture on the suction side was found to be more complex for the smaller tip clearance height considered. For the larger tip clearance height the effect of casing recess was an orderly reduction in the suction side heat transfer as the casing recess height was increased. There was a marked reduction of heat load and peak values on the blade tip upon introduction of casing recess, however only a small reduction was observed on the casing itself. It was reconfirmed that there is a linear relationship between the efficiency and the tip gap height. It was also observed that the recess casing has a small effect on the efficiency but can have a moderating effect on the flow underturning at smaller tip clearances.

  9. Effects of tip clearance and casing recess on heat transfer and stage efficiency in axial turbines

    SciTech Connect

    Ameri, A.A.; Steinthorsson, E.; Rigby, D.L.

    1999-10-01

    Calculations were performed to assess the effect of the tip leakage flow on the rate of heat transfer to blade, blade tip, and casing. The effect on exit angle and efficiency was also examined. Passage geometries with and without casing recess were considered. The geometry and the flow conditions of the GE-E{sup 3} first-stage turbine, which represents a modern gas turbine blade, were used for the analysis. Clearance heights of 0, 1, 1.5, and 3 percent of the passage height were considered. For the two largest clearance heights considered, different recess depths were studied. There was an increase in the thermal load on all the heat transfer surfaces considered due to enlargement of the clearance gap. Introduction, of recessed casing resulted in a drop in the rate of heat transfer on the pressure side, but the picture on the suction side was found to be more complex for the smaller tip clearance height considered. For the larger tip clearance height, the effect of casing recess was an orderly reduction in the suction side heat transfer as the casing recess height was increased. There was a marked reduction of heat load and peak values on the blade tip upon introduction of casing recess; however, only a small reduction was observed on the casing itself. It was reconfirmed that there is a linear relationship between the efficiency and tip gap height. It was also observed that the recess casing has a small effect on the efficiency but can have a moderating effect on the flow underturning at smaller tip clearances.

  10. Restoration of the Spring Snowmelt Recession Below Dams for Native Species Protection in a Changing Climate

    NASA Astrophysics Data System (ADS)

    Yarnell, S.; Epke, G.; Rheinheimer, D. E.; Viers, J. H.

    2011-12-01

    Within Mediterranean-montane ecosystems, the spring snowmelt recession is a distinct feature of the natural annual hydrograph, providing an ecologically significant bridge between the physical disturbance of winter high flows and the biologically stressful conditions of summer low flows. In regulated systems, the snowmelt recession is often absent as the predictable flows are captured behind dams. While restoration of the spring recession is an identified ecological goal, methods for determining suitable ramping rates to transition from high to low flows are lacking, and the hydropower-related cost of such environmental flows under changing climate conditions is uncertain. Here we summarize a quantitative analysis of the spring recession for selected unregulated locations in the Sierra Nevada, California, USA, using an exponential-based function to describe the rate of change in discharge. Results indicate unimpaired recession rates in the Sierra Nevada are consistent across watersheds. We then apply a modeled recession based on these characteristics to an assessment of suitable instream habitat for a native river-breeding amphibian of concern and find that recession rates can be quantitatively modeled to provide ramping rate conditions suitable for native species. Finally, we evaluate the hydropower-related costs of imposing a springtime weekly ramping rate constraint in a regulated Sierran system under various climate warming scenarios. Results show that generation and revenue costs from a ramping rate constraint are low compared to costs associated with increased minimum instream flows throughout the summer, though with climate warming these hydropower costs become more pronounced. Results from these studies collectively provide resource managers with improved knowledge of river dynamics and help guide the prescription of flow regimes in managed river systems to better sustain aquatic and riparian ecosystems in changing hydroclimatic conditions.

  11. Predictive Factors Affecting Long-Term Outcome of Unilateral Lateral Rectus Recession

    PubMed Central

    Yang, Hee Kyung; Kim, Mi-Jin; Hwang, Jeong-Min

    2015-01-01

    Background There are few long-term outcome reports of unilateral lateral rectus (LR) recession for exotropia including a large number of subjects. Previous reports on unilateral LR recession commonly show extremely low rates of initial overcorrection and large exodrifts after surgery suggesting that the surgical dose may be increased. However, little is known of the long-term outcome of a large unilateral LR recession for exotropia. Objectives To determine long-term outcomes and predictive factors of recurrence after a large unilateral LR recession in patients with exotropia. Data Extraction Retrospective analysis was performed on 92 patients aged 3 to 17 years who underwent 10 mm unilateral LR recession for exotropia of ≤ 25 prism diopters (Δ) with prism and alternate cover testing and were followed up for more than 2 years after surgery. Final success rates within 10Δ of exophoria/tropia and 5Δ of esophoria/tropia at distance in the primary position, improvement in stereopsis and the predictive factors for recurrence were evaluated. Results At 24 months after surgery, 54% of patients had ocular alignment meeting the defined criteria of success, 45% had recurrence and 1% had overcorrection. After a mean follow-up of 39 months, 36% showed success, 63% showed recurrence and 1% resulted in overcorrection. The average time of recurrence was 23.4±14.7 months (range, 1–60 months) and the rate of recurrence per person-year was 23% after unilateral LR recession. Predictive factors of recurrence were a larger preoperative near angle of deviation (>16Δ) and larger initial postoperative exodeviation (>5Δ) at distance. Conclusions Long-term outcome of unilateral LR recession for exotropia showed low success rates with high recurrence, thus should be reserved for patients with a small preoperative near angle of exodeviation. PMID:26418819

  12. Mutations of the tyrosinase gene produce autosomal recessive ocular albinism

    SciTech Connect

    King, R.A.; Summers, C.G.; Oetting, W.S.

    1994-09-01

    Albinism has historically been divided into ocular (OA) and oculocutaneous (OCA) types based on the presence or absence of clinically apparent skin and hair involvement in an individual with the ocular features of albinism. The major genes for OCA include the tyrosinase gene in OCA1 and the P gene in OCA2. X-linked and autosomal recessive OA have been described and the responsible genes have not been identified. We now present six Caucasian individuals who have the phenotype of autosomal recessive OA but who have OCA1 as shown by the presence of mutations of the tyrosinase. They had white or very light hair and white skin at birth, and cutaneous pigment developed in the first decade of life. At ages ranging from 1.5-23 years, hair color was dark blond to light brown. The skin had generalized pigment and well developed tan was present on the exposed arm and face skin of four. Iris pigment was present and iris translucency varied. Molecular analysis of the tyrosinase gene, using PCR amplification and direct di-deoxy sequencing showed the following mutations: E398Z/E398Q, P406S/g346a, R402E/T373K, ?/D383N, and H211N/T373K. The homozygous individual was not from a known consanguineous mating. T373K is the most common tyrosinase gene mutation in our laboratory. Three of these mutations are associated with a total loss of tyrosinase activity (g346a splice-site, T373K, and D383N), while four are associated with residual enzyme activity (H211N, R402E, E398Q, and P406S). These studies show that mutations of the tyrosinase gene can produce the phenotype of autosomal recessive OA in an individual who has normal amounts of cutaneous pigment and the ability to tan after birth. This extends the phenotypic range of OCA1 to normal cutaneous pigment after early childhood, and suggest that mutations of the tyrosinase gene account for a significant number of individuals with autosomal recessive OA.

  13. Problems in using p-curve analysis and text-mining to detect rate of p-hacking and evidential value.

    PubMed

    Bishop, Dorothy V M; Thompson, Paul A

    2016-01-01

    Background. The p-curve is a plot of the distribution of p-values reported in a set of scientific studies. Comparisons between ranges of p-values have been used to evaluate fields of research in terms of the extent to which studies have genuine evidential value, and the extent to which they suffer from bias in the selection of variables and analyses for publication, p-hacking. Methods. p-hacking can take various forms. Here we used R code to simulate the use of ghost variables, where an experimenter gathers data on several dependent variables but reports only those with statistically significant effects. We also examined a text-mined dataset used by Head et al. (2015) and assessed its suitability for investigating p-hacking. Results. We show that when there is ghost p-hacking, the shape of the p-curve depends on whether dependent variables are intercorrelated. For uncorrelated variables, simulated p-hacked data do not give the "p-hacking bump" just below .05 that is regarded as evidence of p-hacking, though there is a negative skew when simulated variables are inter-correlated. The way p-curves vary according to features of underlying data poses problems when automated text mining is used to detect p-values in heterogeneous sets of published papers. Conclusions. The absence of a bump in the p-curve is not indicative of lack of p-hacking. Furthermore, while studies with evidential value will usually generate a right-skewed p-curve, we cannot treat a right-skewed p-curve as an indicator of the extent of evidential value, unless we have a model specific to the type of p-values entered into the analysis. We conclude that it is not feasible to use the p-curve to estimate the extent of p-hacking and evidential value unless there is considerable control over the type of data entered into the analysis. In particular, p-hacking with ghost variables is likely to be missed. PMID:26925335

  14. Problems in using p-curve analysis and text-mining to detect rate of p-hacking and evidential value

    PubMed Central

    Thompson, Paul A.

    2016-01-01

    Background. The p-curve is a plot of the distribution of p-values reported in a set of scientific studies. Comparisons between ranges of p-values have been used to evaluate fields of research in terms of the extent to which studies have genuine evidential value, and the extent to which they suffer from bias in the selection of variables and analyses for publication, p-hacking. Methods. p-hacking can take various forms. Here we used R code to simulate the use of ghost variables, where an experimenter gathers data on several dependent variables but reports only those with statistically significant effects. We also examined a text-mined dataset used by Head et al. (2015) and assessed its suitability for investigating p-hacking. Results. We show that when there is ghost p-hacking, the shape of the p-curve depends on whether dependent variables are intercorrelated. For uncorrelated variables, simulated p-hacked data do not give the “p-hacking bump” just below .05 that is regarded as evidence of p-hacking, though there is a negative skew when simulated variables are inter-correlated. The way p-curves vary according to features of underlying data poses problems when automated text mining is used to detect p-values in heterogeneous sets of published papers. Conclusions. The absence of a bump in the p-curve is not indicative of lack of p-hacking. Furthermore, while studies with evidential value will usually generate a right-skewed p-curve, we cannot treat a right-skewed p-curve as an indicator of the extent of evidential value, unless we have a model specific to the type of p-values entered into the analysis. We conclude that it is not feasible to use the p-curve to estimate the extent of p-hacking and evidential value unless there is considerable control over the type of data entered into the analysis. In particular, p-hacking with ghost variables is likely to be missed. PMID:26925335

  15. Detector response and intensity cross-contribution as contributing factors to the observed non-linear calibration curves in mass spectrometric analysis.

    PubMed

    Sie, Meng-Jie; Chen, Bud-Gen; Chang, Chiung Dan; Lin, Chia-Han; Liu, Ray H

    2011-01-21

    It is a common knowledge that detector fatigue causes a calibration curve to deviate from the preferred linear relationship at the higher concentration end. With the adaptation of an isotopically labeled analog of the analyte as the internal standard (IS), cross-contribution (CC) of the intensities monitored for the ions designating the analyte and the IS can also result in a non-linear relationship at both ends. A novel approach developed to assess 'the extent and the effect of [CC]… in quantitative GC-MS analysis' can be extended (a) to examine whether a specific set of CC values is accurate; and (b) to differentiate whether the observed non-linear calibration curve is caused by detector fatigue or the CC phenomenon. Data derived from the exemplar secobarbital (SB)/SB-d(5) system (as di-butyl-derivatives) are used to illustrate this novel approach. Comparing the non-linear nature of calibration data that are empirically observed to that derived from theoretical calculation (with the incorporation of adjustment resulting from the ion CC phenomenon), supports the conclusions that (a) both CC and detector fatigue contribute significantly to the observed non-linear nature of the calibration curve based on ion-pair m/z 207/212; and (b) detector fatigue is the dominating contributor when the calibration curve is based on ion-pair m/z 263/268. PMID:21049098

  16. Observations and analysis of a curved jet in the coma of comet 67P/Churyumov-Gerasimenko

    NASA Astrophysics Data System (ADS)

    Lin, Z.-Y.; Lai, I.-L.; Su, C.-C.; Ip, W.-H.; Lee, J.-C.; Wu, J.-S.; Vincent, J.-B.; La Forgia, F.; Sierks, H.; Barbieri, C.; Lamy, P. L.; Rodrigo, R.; Koschny, D.; Rickman, H.; Keller, H. U.; Agarwal, J.; A'Hearn, M. F.; Barucci, M. A.; Bertaux, J.-L.; Bertini, I.; Bodewits, D.; Cremonese, G.; Da Deppo, V.; Davidsson, B.; Debei, S.; De Cecco, M.; Fornasier, S.; Fulle, M.; Groussin, O.; Gutiérrez, P. J.; Güttler, C.; Hviid, S. F.; Jorda, L.; Knollenberg, J.; Kovacs, G.; Kramm, J.-R.; Kührt, E.; Küppers, M.; Lara, L. M.; Lazzarin, M.; López-Moreno, J. J.; Lowry, S.; Marzari, F.; Michalik, H.; Mottola, S.; Naletto, G.; Oklay, N.; Pajola, M.; Rożek, A.; Thomas, N.; Tubiana, C.

    2016-04-01

    Aims: We analyze the physical properties and dynamical origin of a curved jet of comet 67P/Churyumov-Gerasimenko that was observed repeatedly in several nucleus rotations starting on May 30 and persisting until early August, 2015. Methods: We simulated the motion of dust grains ejected from the nucleus surface under the influence of the gravity and viscous drag effect of the expanding gas flow from the rotating nucleus. Results: The formation of the curved jet is a combination of the size of the dust particles (~0.1-1 mm) and the location of the source region near the nucleus equator. This enhances the spiral feature of the collimated dust stream after the dust is accelerated to a terminal speed on the order of m s-1.

  17. HACE1 deficiency causes an autosomal recessive neurodevelopmental syndrome

    PubMed Central

    Hollstein, Ronja; Parry, David A; Nalbach, Lisa; Logan, Clare V; Strom, Tim M; Hartill, Verity L; Carr, Ian M; Korenke, Georg C; Uppal, Sandeep; Ahmed, Mushtaq; Wieland, Thomas; Markham, Alexander F; Bennett, Christopher P; Gillessen-Kaesbach, Gabriele; Sheridan, Eamonn G; Kaiser, Frank J; Bonthron, David T

    2015-01-01

    Background The genetic aetiology of neurodevelopmental defects is extremely diverse, and the lack of distinctive phenotypic features means that genetic criteria are often required for accurate diagnostic classification. We aimed to identify the causative genetic lesions in two families in which eight affected individuals displayed variable learning disability, spasticity and abnormal gait. Methods Autosomal recessive inheritance was suggested by consanguinity in one family and by sibling recurrences with normal parents in the second. Autozygosity mapping and exome sequencing, respectively, were used to identify the causative gene. Results In both families, biallelic loss-of-function mutations in HACE1 were identified. HACE1 is an E3 ubiquitin ligase that regulates the activity of cellular GTPases, including Rac1 and members of the Rab family. In the consanguineous family, a homozygous mutation p.R219* predicted a truncated protein entirely lacking its catalytic domain. In the other family, compound heterozygosity for nonsense mutation p.R748* and a 20-nt insertion interrupting the catalytic homologous to the E6-AP carboxyl terminus (HECT) domain was present; western blot analysis of patient cells revealed an absence of detectable HACE1 protein. Conclusion HACE1 mutations underlie a new autosomal recessive neurodevelopmental disorder. Previous studies have implicated HACE1 as a tumour suppressor gene; however, since cancer predisposition was not observed either in homozygous or heterozygous mutation carriers, this concept may require re-evaluation. PMID:26424145

  18. Rapid detection of the Clostridium difficile ribotype 027 tcdC gene frame shift mutation at position 117 by real-time PCR and melt curve analysis.

    PubMed

    Wolff, D; Brüning, T; Gerritzen, A

    2009-08-01

    The emergence of the hypervirulent strain Clostridium difficile PCR ribotype 027 has increased the necessity for rapid C. difficile typing tests for clinical and epidemiological purposes. We developed a rapid real-time polymerase chain reaction (PCR) test for the detection of C. difficile. As the target, we chose the tcdC gene, which encodes for a negative regulator in toxin production. A deletion at position 117 of the tcdC gene, which is associated with severe tcdC truncation, is well conserved in all PCR ribotype 027 isolates. Probe sequences of the real-time PCR test were designed to result in distinct melt profiles for sequence variations at positions 117 to 120 of the tcdC gene. The tcdC gene deletion at position 117 was easily detected with real-time PCR and melt curve analysis in all C. difficile ribotype 027 isolates. In five non-027 strains and 46 hospitalised patient samples, melt curve analysis detected no deletion. PCR results were confirmed by DNA sequencing. The combination of real-time PCR and melt curve analysis is a rapid and accurate method for the detection of C. difficile DNA and simultaneous screening for the tcdC gene deletion at position 117, which is closely related to the C. difficile PCR ribotype 027 strain. PMID:19333630

  19. Detection of Ehrlichia canis in canine blood samples by real-time fluorescence resonance energy transfer (FRET) PCR and melting curve analysis.

    PubMed

    Kongklieng, Amornmas; Thanchomnang, Tongjit; Intapan, Pewpan M; Boonmars, Thidarut; Janwan, Penchom; Sanpool, Oranuch; Lulitanond, Viraphong; Taweethavonsawat, Piyanan; Chungpivat, Sudchit; Morakote, Nimit; Maleewong, Wanchai

    2014-09-01

    Ehrlichia canis is a small pleomorphic gram-negative, coccoid, obligatory intracellular bacterium and the cause of canine monocytic ehrlichiosis. A real-time fluorescence resonance energy transfer polymerase chain reaction (real-time FRET PCR) coupled with melting curve analysis was established for detection of E. canis infection in canine blood samples. The VirB9 gene was amplified using one pair of primers and the melting curve analysis was generated by heating the hybridizing probes and amplified products. Eight E. canis-infected dog blood samples were initially identified using the Giemsa staining/microscopic method followed by conventional PCR (cPCR)/Sanger sequencing for confirmation. The sensitivity and specificity of the real-time FRET PCR detection were 87.5% and 100%, respectively and the limit of detection was 6.6 x 10(3) copies of positive E. canis control plasmids. The real-time FRET PCR with melting curve analysis reported here is better than microscopic visualization or cPCR because the method is not affected by the false bias inherent in the microscopic method. Furthermore, many samples can be processed rapidly at the same time. This convenient tool is beneficial as an alternative assay for the epidemiologic study of canine ehrlichiosis as well as for eradication of these organisms in prevention and control programs in endemic areas. PMID:25417518

  20. A statistical model for the effect of casing treatment recesses on compressor rotor performance

    SciTech Connect

    Nezym, Vitaliy

    2007-08-15

    The tip clearance between a compressor's rotating blades and its casing has an unfavorable influence on performance. By applying an abradable coating (insert) to the casing over the rotating blades, this tip clearance can be reduced to practically zero. A rather frequent variant is for the rotor blade tips to carve an entire annular recess in this coating. Rectangular recesses of various configurations have been tested in several different researches. The results of these investigations are processed using the Group Method of Data Handling. A statistical model is developed that predicts the influence of rectangular recesses on a compressor stage's efficiency and stable operating (flow) range. The model takes into account the six principal geometric parameters of a rectangular recess, as well as the Lieblein rotor diffusion factor. Analysis of the derived model has also determined which of these parameters are the most influential. Rectangular entire annular recesses are one of the simplest and most progressive types of casing treatment, and this paper concludes with an overview of existing research that supports this claim. (author)

  1. Comparative study of two surgical techniques for root coverage of large recessions in heavy smokers.

    PubMed

    Reino, Danilo M; Maia, Luciana P; Novaes, Arthur B; Souza, Sérgio L S

    2015-01-01

    Reduced root coverage due to diminished periodontal vascularity can be expected in heavy smokers. The aim of this study was to evaluate the root coverage obtained for large gingival recessions in heavy smokers using two different surgical techniques. Twenty heavy smokers were selected. Each patient had large, bilateral Miller class I or II gingival recessions (Control Group (CG): 3.30 ± 1.29; Test Group (TG): 3.45 ± 0.80) on nonmolar teeth. Clinical measurements of probing pocket depth (PPD), clinical attachment level (CAL), recession height (RH), keratinized mucosa height (KMH), and keratinized mucosa thickness (KMT) were determined at baseline and after 12 months. One side received a coronally positioned flap (CPF), while the contralateral side received the extended flap technique (EFT), both procedures carried out in conjunction with a subepithelial connective tissue graft (SCTG). Saliva samples to measure cotinine levels were taken at baseline and after 12 months as an indicator of the level of exposure to nicotine. Intergroup and intragroup analysis showed no statistical differences for the evaluated clinical parameters. Patients maintained the same exposure to smoke during the evaluation period. Both techniques resulted in low root coverage (CPF: 48.60%; EFT: 54.28%), but both techniques were effective in decreasing the gingival recessions (P ≤ 0.01). The variables smoke exposure, root coverage, and the thickness and height of keratinized tissue were subjected to linear regression. Regardless of the surgical technique used, heavy smoking strongly limits root coverage, especially for large recessions. PMID:26171447

  2. Quantitative real-time RT-PCR using hybridization probes and imported standard curves for cytokine gene expression analysis.

    PubMed

    Kühne, Benedikte Sabina; Oschmann, Patrick

    2002-11-01

    Quantitative real-time or kinetic RT-PCR is increasingly used for the quantification of specific mRNA targets, especially in clinical applications. To quantify the mRNA of cytokines and their receptors, which play important roles in the pathogenesis of autoimmune diseases such as multiple sclerosis, we have developed quantitative two-step RT-PCR assays for IL-4, IL-4R, IFN-gamma, IFN-beta, and the housekeeping gene porphobilinogen deaminase (PBGD). The LightCycler system was used to quantify the copy numbers with the sequence-specific hybridization probe detection format. The quantification was carried out on the basis of standard curves generated with external homologous plasmids for each different parameter in relation to the gene expression of PBGD. Therefore, this procedure represents a relative quantification method with external standards, as the standard curves were used to obtain an absolute value for the copy numbers of the targets and the reference (PBGD). The new software version 3.5 of the LightCycler system allows the construction of a single parameter-dependent plasmid standard curve for the quantification of unknown samples from different runs. Here we demonstrate how to achieve precise and reproducible quantification, even when using measurements from different PCR runs. PMID:12449386

  3. Recessed light fixtures: Infiltration energy loss

    SciTech Connect

    Bennett, S.M.; Perez-Blanco, H. )

    1994-06-01

    This article reports that a recent study revealed that fluorescent bulbs can reduce convective energy losses by 15--65% as compared to incandescent bulbs. Recessed light fixtures are commonly installed in offices and homes. However, a problem arises in homes when the fixtures are set in the ceiling such that the top of the light fixture is exposed to the unconditioned air in the attic. Because some air flow is necessary around the light to avoid overheating, the manufacturers do not make all the fixtures leak tight, only those that are rated for lower wattage bulbs. The need for cooling the fixture may conflict with some building efficiency codes.

  4. CFLs in Recessed Downlights: Technical Challenges

    SciTech Connect

    Ledbetter, Marc R.; McCullough, Jeffrey J.; Dillon, Heather E.; Sandahl, Linda J.; Gordon, Kelly L.

    2005-05-09

    Recessed downlights are the most popular residential lighting fixture in the United States representing about 12 percent of installed residential lighting fixtures and 15 percent of total lighting energy use nationwide. We estimate 400 million recessed downlights are currently installed in American homes, almost all using incandescent light sources. In the year 2000, only 0.44 percent of recessed cans sold were hard-wired for using pin-based CFLs. Recessed downlights consume energy in three ways. First, their incandescent light sources use energy directly, drawing 65 to 150 watts. Second, they consume energy indirectly by adding heat from their light sources to air-conditioning loads. Third, since most are not airtight, they also consume energy indirectly by allowing conditioned air to escape into unconditioned areas above the downlights, such as attics. PNNL calculated potential energy savings and found that if a 65W incandescent non-airtight downlight is replaced with a 26W CFL ICAT downlight operated at 3 hrs per day savings will be 126 kWh/yr. Early reflector CFLs have had high return rates primarily because of failure due to thermal related stress. A PNNL laboratory test of ten commercially available R-CFLs selected from retail store shelves showed almost all operated above their manufacturer rated maximum operating temperatures when they were installed and tested in ICAT downlights in a simulated insulated ceiling apparatus. DOE asked PNNL to investigate the development and introduction of both pin-based and screw-based CFLs for use in ICAT fixtures. PNNL invited manufacturers to submit lamps to a procurement program. PNNL conducted short- and long-term thermal testing of the lamps to measure performance parameters affected by elevated temperatures. 8 out of 10 R-CFLs (secrew-based lamps) failed the long-tem testing. Five out of nine CFL-ICAT (pin-based CFL) fixtures passed the long-term test, surviving a full year of operation in a simulated insulated ceiling apparatus, while maintaining at least 80% of initial lumens at 40% of rated life. Of those five products, two were withdrawn from the market due to poor sales, probably because of the high prices on the products. Three remain on the market. PNNL plans to initiate another R-CFL technology procurement in the winter of 2004/2005 to bring more high-quality R-CFL models to market. PNNL developed a number of design ideas for improving the thermal performance of pin-based CFL ICAT downlights for use in future activities.

  5. Fuel compositions for lessening valve seat recession

    SciTech Connect

    Johnston, T.E.; Dorer, C.J. Jr.

    1987-04-21

    A fuel composition is described for internal combustion engines comprising a major amount of a liquid hydrocarbon fuel and a minor, property improving amount sufficient to reduce valve seat recession when the fuel is used in an internal combustion engine of (A) at least one hydrocarbon-soluble alkali or alkaline earth metal containing composition containing at least 8 aliphatic carbon atoms and (B) at least one hydrocarbon-soluble ashless dispersant wherein (A) is the alkali metal or alkaline earth metal salt of a sulfur acid, a carboxylic acid or a phenol.

  6. Atlas of fatigue curves

    SciTech Connect

    Boyer, H.E.

    1986-01-01

    This Atlas was developed to serve engineers who are looking for fatigue data on a particular metal or alloy. Having these curves compiled in a single book will also facilitate the computerization of the involved data. It is pointed out that plans are under way to make the data in this book available in ASCII files for analysis by computer programs. S-N curves which typify effects of major variables are considered along with low-carbon steels, medium-carbon steels, alloy steels, HSLA steels, high-strength alloy steels, heat-resisting steels, stainless steels, maraging steels, cast irons, and heat-resisting alloys. Attention is also given to aluminum alloys, copper alloys, magnesium alloys, molybdenum, tin alloys, titanium and titanium alloys, zirconium, steel castings, closed-die forgings, powder metallurgy parts, composites, effects of surface treatments, and test results for component parts.

  7. Evaluation of the Capacity of PCR and High-Resolution Melt Curve Analysis for Identification of Mixed Infection with Mycoplasma gallisepticum Strains

    PubMed Central

    Ghorashi, Seyed A.; Kanci, Anna; Noormohammadi, Amir H.

    2015-01-01

    Pathogenicity and presentation of Mycoplasma gallisepticum (MG) infection may differ from one strain to another and this may have implications on control measures. Infection of individual birds with more than one MG strain has been reported. A PCR followed by high resolution melt (HRM) curve analysis has been developed in our laboratory and routinely used for detection and differentiation of MG strains. However the potential of this test for identification of MG strains in a mixed specimen has not been evaluated. In the present study, the capability of PCR-HRM curve analysis technique, targeting vlhA and pvpA genes was assessed for identification of individual MG strains in a mixed population. Different DNA ratios of two MG strains from 1 to 10-4 ng were tested with some generated conventional and normalized curves distinct from those of individual strains alone. Using genotype confidence percentages (GCP) generated from HRM curve analysis, it was found that vlhA PCR-HRM was more consistent than pvpA PCR-HRM for the detection of MG ts-11 vaccine strain mixed with any of the MG strains 6/85, F, S6 or a field isolate. The potential of vlhA PCR-HRM to detect mixed MG strains in a specimen was found to be primarily dependent on quantity and proportion of the target DNAs in the mixture. This is the first study examining the capacity of PCR-HRM technique for identification of individual MG strains in a mixed strain population. PMID:25970590

  8. Autosomal recessive nonsyndromic deafness genes: a review

    PubMed Central

    Duman, Duygu; Tekin, Mustafa

    2013-01-01

    More than 50 percent of prelingual hearing loss is genetic in origin, and of these up to 93 percent are monogenic autosomal recessive traits. Some forms of genetic deafness can be recognized by their associated syndromic features, but in most cases, hearing loss is the only finding and is referred to as nonsyndromic deafness. To date, more than 700 different mutations have been identified in one of 42 genes in individuals with autosomal recessive nonsyndromic hearing loss (ARNSHL). Reported mutations in GJB2, encoding connexin 26, makes this gene the most common cause of hearing loss in many populations. Other relatively common deafness genes include SLC26A4, MYO15A, OTOF, TMC1, CDH23, and TMPRSS3. In this report we summarize genes and mutations reported in families with ARNSHL. Founder effects were demonstrated for some recurrent mutations but the most significant findings are the extreme locus and allelic heterogeneity and different spectrum of genes and mutations in each population. PMID:22652773

  9. Quantitative analysis of electrophoresis data: novel curve fitting methodology and its application to the determination of a protein-DNA binding constant.

    PubMed Central

    Shadle, S E; Allen, D F; Guo, H; Pogozelski, W K; Bashkin, J S; Tullius, T D

    1997-01-01

    A computer program, GelExplorer, which uses a new methodology for obtaining quantitative information about electrophoresis has been developed. It provides a straightforward, easy-to-use graphical interface, and includes a number of features which offer significant advantages over existing methods for quantitative gel analysis. The method uses curve fitting with a nonlinear least-squares optimization to deconvolute overlapping bands. Unlike most curve fitting approaches, the data is treated in two dimensions, fitting all the data across the entire width of the lane. This allows for accurate determination of the intensities of individual, overlapping bands, and in particular allows imperfectly shaped bands to be accurately modeled. Experiments described in this paper demonstrate empirically that the Lorentzian lineshape reproduces the contours of an individual gel band and provides a better model than the Gaussian function for curve fitting of electrophoresis bands. Results from several fitting applications are presented and a discussion of the sources and magnitudes of uncertainties in the results is included. Finally, the method is applied to the quantitative analysis of a hydroxyl radical footprint titration experiment to obtain the free energy of binding of the lambda repressor protein to the OR1 operator DNA sequence. PMID:9016637

  10. Permanent prostate brachytherapy: Dosimetric results and analysis of a learning curve with a dynamic dose-feedback technique

    SciTech Connect

    Acher, Peter . E-mail: peter.acher@gstt.nhs.uk; Popert, Rick; Nichol, Janette; Potters, Louis; Morris, Stephen; Beaney, Ronald

    2006-07-01

    Purpose: A permanent prostate brachytherapy (PPB) program utilizing intraoperative inverse-planned dynamic dose-feedback was initiated without prior firsthand experience of alternative techniques. The purpose of this study is to assess the dosimetric learning curve associated with this approach. Methods and Materials: A total of 77 patients underwent PPB implants as monotherapy for localized prostate cancer to a prescription dose of 145 Gy with loose 125I seeds between December 2003 and June 2004. Intraoperative and postoperative dosimetric values, total implanted radioactivity, and operating room (OR) times were compared by sequential case number for all cases. Results: The median intraoperative dosimetric values were: D90 (the minimum dose to 90% of the prostate) = 170 Gy (range, 135-203 Gy), V100 (the volume of the prostate that receives 100% of the prescription dose) = 96% (range, 86-100), V150 = 66% (range, 34-86). Median postoperative dosimetric values were as follows: D90 = 168 Gy (range, 132-197 Gy), V100 = 95% (range, 86-99), V150 = 74% (range, 51-84). Median implanted activity was 0.79 mCi per cubic centimeter of prostate (range, 0.541-1.13). There was no significant correlation by case number on any postoperative dosimetric parameter studied. Door-to-door OR time was reduced from median 138 to 97.5 min per case at the end of the series with a correlation coefficient of -0.76 for the initial 28 cases. Conclusion: Satisfactory dosimetric parameters can be achieved from the outset without a learning curve effect in an appropriately trained environment. The learning curve for dynamic dose-feedback PPB in a clinic naive to other techniques is apparent in terms of OR time.

  11. The Process of Integration of Newcomers at School: Students and Gender Networking during School Recess

    ERIC Educational Resources Information Center

    Rodriguez-Navarro, Henar; Garca-Monge, Alfonso; Rubio-Campos, Maria del Carmen

    2014-01-01

    This article examines the data obtained through a year-long ethnographic study of students from a Spanish primary school, and sheds light on their use of gender code networks during school recess. The results of this analysis confirm the conclusions on student interaction drawn by other studies (group segregation regarding age and gender and,

  12. Citizen Support for Northern Ohio Community College Funding Initiatives during an Economic Recession Recovery

    ERIC Educational Resources Information Center

    Flores, Patricia

    2013-01-01

    The current research, "Citizen Support for Northern Ohio Community College Funding Initiatives during an Economic Recession Recovery", asks the question: Do the citizens of Northern Ohio support community college funding during difficult economic times? Based on the theory of Stakeholder Analysis, the purpose of this concurrent,…

  13. The Process of Integration of Newcomers at School: Students and Gender Networking during School Recess

    ERIC Educational Resources Information Center

    Rodriguez-Navarro, Henar; García-Monge, Alfonso; Rubio-Campos, Maria del Carmen

    2014-01-01

    This article examines the data obtained through a year-long ethnographic study of students from a Spanish primary school, and sheds light on their use of gender code networks during school recess. The results of this analysis confirm the conclusions on student interaction drawn by other studies (group segregation regarding age and gender and,…

  14. Is the Elimination of Recess in School a Violation of a Child's Basic Human Rights?

    ERIC Educational Resources Information Center

    Dubroc, Alicia M.

    2007-01-01

    The elimination of recess in schools across the country is becoming a normal occurrence in many communities, large and small. In each study presented in this content analysis, we find that free time and unstructured play is indeed essential to a child's healthy cognitive development. Article 31 of the United Nations Convention on the Rights of…

  15. Arbitrarily Curved and Twisted Space Beams. Ph.D. Thesis - Va. Polytech. Inst. and State Univ.; [Elastic Deformation, Stress Analysis

    NASA Technical Reports Server (NTRS)

    Hunter, W. F.

    1974-01-01

    A derivation of the equations which govern the deformation of an arbitrarily curved and twisted space beam is presented. These equations differ from those of the classical theory in that (1) extensional effects are included; (2) the strain-displacement relations are derived; and (3) the expressions for the stress resultants are developed from the strain displacement relations. It is shown that the torsional stress resultant obtained by the classical approach is basically incorrect except when the cross-section is circular. The governing equations are given in the form of first-order differential equations. A numerical algorithm is given for obtaining the natural vibration characteristics and example problems are presented.

  16. Comparison of environmental TLD (thermoluminescent dosimeter) results obtained using glow curve deconvolution and region of interest analysis

    SciTech Connect

    Not Available

    1987-01-01

    We tested a Harshaw Model 4000 TLD Reader in the Sandia Environmental TLD Program. An extra set of LiF TLD-700 chips were prepared for each field location and calibration level. At the end of quarter one, half of the TLDs were read on the Model 4000 and the other half were read on our standard Harshaw Model 2000. This presentation compares the results of the two systems. The Model 4000 results are reported for two regions of interest and for background subtraction using Harshaw Glow Curve Deconvolution Software.

  17. Direct Analysis of JV-Curves Applied to an Outdoor-Degrading CdTe Module (Presentation)

    SciTech Connect

    Jordan, D; Kurtz, S.; Ulbrich, C.; Gerber, A.; Rau, U.

    2014-03-01

    We present the application of a phenomenological four parameter equation to fit and analyze regularly measured current density-voltage JV curves of a CdTe module during 2.5 years of outdoor operation. The parameters are physically meaningful, i.e. the short circuit current density Jsc, open circuit voltage Voc and differential resistances Rsc, and Roc. For the chosen module, the fill factor FF degradation overweighs the degradation of Jsc and Voc. Interestingly, with outdoor exposure, not only the conductance at short circuit, Gsc, increases but also the Gsc(Jsc)-dependence. This is well explained with an increase in voltage dependent charge carrier collection in CdTe.

  18. Flow Curve Determination at Large Plastic Strain Levels: Limitations of the Membrane Theory in the Analysis of the Hydraulic Bulge Test

    NASA Astrophysics Data System (ADS)

    Lemoine, X.; Iancu, A.; Ferron, G.

    2011-05-01

    Nowadays, an accurate determination of the true stress-strain curve is a key-element for all finite element (FE) forming predictions. Since the introduction of Advanced High Strength Steels (AHSS) for the automotive market, the standard uniaxial tension test suffers the drawback of relatively low uniform elongations. The extrapolation of the uniaxial stress-strain curve up to large strains is not without consequence in forming predictions—especially formability and springback. One of the means to solve this problem is to use experimental tests where large plastic strain levels can be reached. The hydraulic bulge test is one of these tests. The effective plastic strain levels reached in the bulge test are of about 0.7. From an experimental standpoint, the biaxial flow stress is estimated using measurement of fluid pressure, and calculation of thickness and curvature at the pole, via appropriate measurements and assumptions. The biaxial stress at the pole is determined using the membrane equilibrium equation. The analysis proposed in this paper consists of performing "virtual experiments" where the results obtained by means of FE calculations are used as input data for determining the biaxial stress-strain law in agreement with the experimental procedure. In this way, a critical discussion of the experimental procedure can be made, by comparing the "experimental" stress-strain curve (Membrane theory curve) with the "reference" one introduced in the simulations. In particular, the influences of the "(die diameter)/thickness" ratio and of the plastic anisotropy are studied, and limitations of the hydraulic bulge test analysis are discussed.

  19. Coverage of gingival recession using tunnel connective tissue graft technique

    PubMed Central

    Khuller, Nitin

    2009-01-01

    The recession of gingiva is increasingly becoming a more prominent condition in the oral health of many patients and should be treated at its earliest detection. The multi-factorial etiology, decision modality, and current trends followed in treatment of gingival recession are discussed in this presentation. The correction of class I and II gingival recessions are presented as a means of minimizing surgical trauma and achieving predictable aesthetic results. In this case report, I present an alternative technique in treating gingival recession- the tunnel connective tissue graft. PMID:20407659

  20. CONSTRUCTION OF AN EARTH MODEL: ANALYSIS OF EXOPLANET LIGHT CURVES AND MAPPING THE NEXT EARTH WITH THE NEW WORLDS OBSERVER

    SciTech Connect

    Oakley, P. H. H.; Cash, W.

    2009-08-01

    The orbital light curve of a terrestrial exoplanet will likely contain valuable information about the surface and atmospheric features of the planet, both in its overall shape and hourly variations. We have constructed an empirically based code capable of simulating observations of the Earth from any orientation, at any time of year with continuously updated cloud and snow coverage with a New Worlds Observatory. By simulating these observations over a full orbital revolution at a distance of 10 pc we determine that the detection of an obliquity or seasonal terrain change is possible at low inclinations. In agreement with other studies, a 4 m New Worlds Observer can accurately determine the rotation rate of the planet at a success rate from {approx}30% to 80% with only 5 days of observations depending on the signal to noise of the observations. We also attempt simple inversions of these diurnal light curves to sketch a map of the reflecting planet's surface features. This mapping technique is only successful with highly favorable systems and in particular requires that the cloud coverage must be lower than the Earth's average. Our test case of a 2 M {sub +} planet at 7 pc distance with low exo-zodiacal light and 25% cloud coverage produced crude, but successful results. Additionally, with these highly favorable systems NWO may be able to discern the presence of liquid surface water (or other smooth surfaces) though it requires a complex detection available only at crescent phases in high inclination systems.

  1. PARAMETER ESTIMATION AND CONFIDENCE REGIONS IN THE METHOD OF LIGHT-CURVE SIMULATIONS FOR THE ANALYSIS OF POWER DENSITY SPECTRA

    SciTech Connect

    Mueller, Martin; Madejski, Greg

    2009-07-20

    The method of light-curve simulations is a tool that has been applied to X-ray monitoring observations of active galactic nuclei for the characterization of the power density spectrum (PDS) of temporal variability and measurement of associated break frequencies (which appear to be an important diagnostic for the mass of the black hole in these systems as well as their accretion state). It relies on a model for the PDS that is fitted to the observed data. The determination of confidence regions on the fitted model parameters is of particular importance, and we show how the Neyman construction based on distributions of estimates may be implemented in the context of light-curve simulations. We believe that this procedure offers advantages over the method used in earlier reports on PDS model fits, not least with respect to the correspondence between the size of the confidence region and the precision with which the data constrain the values of the model parameters. We plan to apply the new procedure to existing RXTE and XMM-Newton observations of Seyfert I galaxies as well as RXTE observations of the Seyfert II galaxy NGC 4945.

  2. Analysis of MOST light curves of five young stars in Taurus-Auriga and Lupus 3 star-forming regions

    NASA Astrophysics Data System (ADS)

    Siwak, Michal; Rucinski, Slavek M.; Matthews, Jaymie M.; Kuschnig, Rainer; Guenther, David B.; Moffat, Anthony F. J.; Sasselov, Dimitar; Weiss, Werner W.

    2011-08-01

    Continuous photometric observations of five young stars obtained by the MOST satellite in 2009 and 2010 in the Taurus and Lupus star formation regions are presented. Using light-curve modelling under the assumption of internal invariability of spots, we obtained small values of the solar-type differential-rotation parameter (k = 0.0005-0.009) for three spotted weak-line T Tauri stars, V410 Tau, V987 Tau and Lupus 3-14; for another spotted weak-line T Tauri star (WTTS), Lupus 3-48, the data are consistent with a rigidly rotating surface (k = 0). Three flares of similar rise (4 min and 30 s) and decay (1 h and 45 min) times were detected in the light curve of Lupus 3-14. The brightness of the classical T Tauri star RY Tau continuously decreased over 3 weeks of its observations with a variable modulation not showing any obvious periodic signal. Based on data from the MOST satellite, a Canadian Space Agency mission, jointly operated by Dynacon Inc., the University of Toronto Institute of Aerospace Studies and the University of British Columbia, with the assistance of the University of Vienna.

  3. Parameter Estimation and Confidence Regions in the Method of Light Curve Simulations for the Analysis of Power Density Spectra

    SciTech Connect

    Mueller, M.; Madejski, G.

    2009-05-20

    The Method of Light Curve Simulations is a tool that has been applied to X-ray monitoring observations of Active Galactic Nuclei (AGN) for the characterization of the Power Density Spectrum (PDS) of temporal variability and measurement of associated break frequencies (which appear to be an important diagnostic for the mass of the black hole in these systems as well as their accretion state). It relies on a model for the PDS that is fit to the observed data. The determination of confidence regions on the fitted model parameters is of particular importance, and we show how the Neyman construction based on distributions of estimates may be implemented in the context of light curve simulations. We believe that this procedure offers advantages over the method used in earlier reports on PDS model fits, not least with respect to the correspondence between the size of the confidence region and the precision with which the data constrain the values of the model parameters. We plan to apply the new procedure to existing RXTE and XMM observations of Seyfert I galaxies as well as RXTE observations of the Seyfert II galaxy NGC 4945.

  4. An Exploratory Analysis of Personality, Attitudes, and Study Skills on the Learning Curve within a Team-based Learning Environment

    PubMed Central

    Henry, Teague; Campbell, Ashley

    2015-01-01

    Objective. To examine factors that determine the interindividual variability of learning within a team-based learning environment. Methods. Students in a pharmacokinetics course were given 4 interim, low-stakes cumulative assessments throughout the semester and a cumulative final examination. Students’ Myers-Briggs personality type was assessed, as well as their study skills, motivations, and attitudes towards team-learning. A latent curve model (LCM) was applied and various covariates were assessed to improve the regression model. Results. A quadratic LCM was applied for the first 4 assessments to predict final examination performance. None of the covariates examined significantly impacted the regression model fit except metacognitive self-regulation, which explained some of the variability in the rate of learning. There were some correlations between personality type and attitudes towards team learning, with introverts having a lower opinion of team-learning than extroverts. Conclusion. The LCM could readily describe the learning curve. Extroverted and introverted personality types had the same learning performance even though preference for team-learning was lower in introverts. Other personality traits, study skills, or practice did not significantly contribute to the learning variability in this course. PMID:25861101

  5. A rare case of respiratory disorders associated with two autosomal recessive diseases and male infertility.

    PubMed

    Mendeluk, Gabriela Ruth; Costa, Sergio López; Scigliano, Sergio; Menga, Guillermo; Demiceu, Sergio; Palaoro, Luis Alberto

    2013-01-01

    The study of nasal ciliary beat frequency (CBF) and ultrastructure may contribute to the understanding of pathognomonic cases of male infertility associated with defects in sperm motility. This study was designed to report a particular case of male infertility, characterized by the association of two respiratory autosomal recessive genetic diseases (alpha-1-antitrypsin deficiency [AAT-D] and primary ciliary dyskinesia [PCD]). A 39-year-old patient with complete sperm immotility, AAT-D, and bronchiectasis was studied in the Laboratory of Male Fertility, the Department of Urology, the Respiratory Center of a Pediatric Hospital, and in the Department of Clinical Medicine of a Rehabilitation Respiratory Hospital. Family history, physical examination, hormonal analysis, microbial assays, semen analysis, nasal ciliary function, and structure study by digital high-speed video photography and transmission electron microscopy are described. A noninvasive nasal biopsy to retrieve ciliated epithelium lining the inferior surface of the inferior nasal turbinates was performed and CBF was determined. Beat pattern was slightly curved and rigid, not wide, and metacronic in all the observed fields analyzed. CBF was 8.2 Hz in average (reference value, 10-15 Hz) Ultrastructural assay revealed absence of the inner dynein arms in 97% of the cilia observed. The final infertility accurate diagnosis was achieved by the study of nasal CBF and ultrastructure contributing to the patient health management and genetic counseling while deciding fatherhood. Beyond this particular case, the present report may open a new field of studies in male infertility, mainly in cases of asthenozoospermia. PMID:23772318

  6. A rare case of respiratory disorders associated with two autosomal recessive diseases and male infertility

    PubMed Central

    Costa, Sergio López; Scigliano, Sergio; Menga, Guillermo; Demiceu, Sergio; Palaoro, Luis Alberto

    2013-01-01

    The study of nasal ciliary beat frequency (CBF) and ultrastructure may contribute to the understanding of pathognomonic cases of male infertility associated with defects in sperm motility. This study was designed to report a particular case of male infertility, characterized by the association of two respiratory autosomal recessive genetic diseases (alpha-1-antitrypsin deficiency [AAT-D] and primary ciliary dyskinesia [PCD]). A 39-year-old patient with complete sperm immotility, AAT-D, and bronchiectasis was studied in the Laboratory of Male Fertility, the Department of Urology, the Respiratory Center of a Pediatric Hospital, and in the Department of Clinical Medicine of a Rehabilitation Respiratory Hospital. Family history, physical examination, hormonal analysis, microbial assays, semen analysis, nasal ciliary function, and structure study by digital high-speed video photography and transmission electron microscopy are described. A noninvasive nasal biopsy to retrieve ciliated epithelium lining the inferior surface of the inferior nasal turbinates was performed and CBF was determined. Beat pattern was slightly curved and rigid, not wide, and metacronic in all the observed fields analyzed. CBF was 8.2 Hz in average (reference value, 10–15 Hz) Ultrastructural assay revealed absence of the inner dynein arms in 97% of the cilia observed. The final infertility accurate diagnosis was achieved by the study of nasal CBF and ultrastructure contributing to the patient health management and genetic counseling while deciding fatherhood. Beyond this particular case, the present report may open a new field of studies in male infertility, mainly in cases of asthenozoospermia. PMID:23772318

  7. Anatomical curve identification

    PubMed Central

    Bowman, Adrian W.; Katina, Stanislav; Smith, Joanna; Brown, Denise

    2015-01-01

    Methods for capturing images in three dimensions are now widely available, with stereo-photogrammetry and laser scanning being two common approaches. In anatomical studies, a number of landmarks are usually identified manually from each of these images and these form the basis of subsequent statistical analysis. However, landmarks express only a very small proportion of the information available from the images. Anatomically defined curves have the advantage of providing a much richer expression of shape. This is explored in the context of identifying the boundary of breasts from an image of the female torso and the boundary of the lips from a facial image. The curves of interest are characterised by ridges or valleys. Key issues in estimation are the ability to navigate across the anatomical surface in three-dimensions, the ability to recognise the relevant boundary and the need to assess the evidence for the presence of the surface feature of interest. The first issue is addressed by the use of principal curves, as an extension of principal components, the second by suitable assessment of curvature and the third by change-point detection. P-spline smoothing is used as an integral part of the methods but adaptations are made to the specific anatomical features of interest. After estimation of the boundary curves, the intermediate surfaces of the anatomical feature of interest can be characterised by surface interpolation. This allows shape variation to be explored using standard methods such as principal components. These tools are applied to a collection of images of women where one breast has been reconstructed after mastectomy and where interest lies in shape differences between the reconstructed and unreconstructed breasts. They are also applied to a collection of lip images where possible differences in shape between males and females are of interest. PMID:26041943

  8. Evaluation of hemoglobin performance in the assessment of iron stores in feto-maternal pairs in a high-risk population: receiver operating characteristic curve analysis

    PubMed Central

    Jaime-Pérez, José Carlos; García-Arellano, Gisela; Méndez-Ramírez, Nereida; González-Llano, Óscar; Gómez-Almaguer, David

    2015-01-01

    Objective By applying receiver operating characteristic curve analysis, the objective of this study was to see whether hemoglobin levels reflect body iron stores in a group of pregnant women at term who, by using serum ferritin as the reference test, had a high pre-test probability of having iron deficiency anemia. Likewise, we evaluated the ability of hemoglobin and maternal serum ferritin levels to predict iron deficiency anemia in newborns. Methods Hemoglobin and serum ferritin were measured in 187 pregnant women at term belonging to a group with a high pre-test probability of iron deficiency anemia and their newborns. Women with Hb <11.0 g/dL and newborns with cord Hb <13.0 g/dL were classified as anemic. A serum ferritin <12.0 μg/L in women and a cord blood serum ferritin <35.0 μg/L were considered to reflect empty iron stores. Receiver operating characteristic curve analysis was applied to select the cut-off points that better reflected iron stores. Results The Hb cut-off point selected by receiver operating characteristic curve analysis in women was <11.5 g/dL (sensitivity: 60.82, specificity: 53.33%, Youden Index: 0.450). Most of the newborns had normal Hb which precluded this analysis. Maternal Hb <11.0 g/dL was the cut-off point that best reflected iron deficiency anemia in newborns (sensitivity: 55.88%, specificity: 57.24%, Youden Index: 0.217). The best cut-off point of maternal serum ferritin to reflect empty iron stores in newborns was <6.0 μg/L (sensitivity: 76.47%, specificity: 31.58%, Youden Index: 0.200). Conclusion Hemoglobin concentration performed poorly to detect iron deficiency anemia in women at term with high risk for iron deficiency and their newborns. PMID:26041420

  9. Palmoplantar hyperkeratosis in Irish terriers: evidence of autosomal recessive inheritance.

    PubMed

    Binder, H; Arnold, S; Schelling, C; Suter, M; Wild, P

    2000-02-01

    An abnormal development of the epidermis of the footpad was observed in Irish terriers. At the age of six months, the affected animals developed smooth parchment-like footpads. The pad epidermis then hardened and grew lateral cone-like protrusions of up to 5 mm in diameter. Fissures and cracks developed and these predisposed the animal to secondary infection. The repeated occurrence in subsequent generations led to the assumption of a hereditary form of hyperkeratosis. Evidence for an autosomal recessive mode of inheritance was derived from a retrospective analysis of the breeder's records. The clinical, histopathological and ultrastructural features of the disease are presented and the genetic transmission and its implications discussed. PMID:10701186

  10. Analysis of curved folds and fault/fold terminations in the southern Upper Magdalena Valley of Colombia

    NASA Astrophysics Data System (ADS)

    Jiménez, Giovanny; Rico, John; Bayona, German; Montes, Camilo; Rosero, Alexis; Sierra, Daniel

    2012-11-01

    We use surface and subsurface fold and fault geometries to document curved geometry of folds, along-strike termination of faults/folds and the change of dip of regional faults in four structural areas in the southern part of the Upper Magdalena Valley Basin. In La Cañada area, strike-slip deformation is dominant and cuts former compressional structures; faults and folds of this area end northward abruptly near Rio Paez. To the north of Paez River is the La Hocha area that includes the Tesalia Syncline and La Hocha Anticline, two curved folds that plunge at the same latitude. The southern domain of La Hocha Anticline is asymmetric and bounded by faults in both flanks, whereas the symmetry of the northern domain is related to subsurface fault bending. Paleomagnetic components uncovered in Jurassic rocks suggest a clockwise rotation of 15.2 ± 11.4 in the southern domain, and 31.7 ± 14.4 in the northern domain. The Iquira Area, North of La Hocha, the internal structure is controlled by east-verging faults that end abruptly to the north of this area. The northernmost area is the Upar area that includes fault systems with opposite vergence; west-verging faults at the east of this area decapitate east-verging faults and folds. Paleomagnetic data, geologic mapping and regional structural cross-sections suggest that: (1) pre-existing basement structure controls the curved geometry of La Hocha Anticline; (2) along-strike changes in structural style between adjacent areas and along-strike termination of faults and folds are related to the location of northwest-striking transverse structures in the subsurface; and (3) at least two deformation phases are documented: an Eocene-Oligocene phase associated with the growth of folds along detachment levels within Mesozoic rocks; and a late Miocene phase associated with transpressive faulting along the Chusma and San Jacinto faults. The latter event drove clockwise rotation of the La Hocha Anticline.

  11. Refined hierarchical kinematics quasi-3D Ritz models for free vibration analysis of doubly curved FGM shells and sandwich shells with FGM core

    NASA Astrophysics Data System (ADS)

    Fazzolari, Fiorenzo A.; Carrera, Erasmo

    2014-02-01

    In this paper, the Ritz minimum energy method, based on the use of the Principle of Virtual Displacements (PVD), is combined with refined Equivalent Single Layer (ESL) and Zig Zag (ZZ) shell models hierarchically generated by exploiting the use of Carrera's Unified Formulation (CUF), in order to engender the Hierarchical Trigonometric Ritz Formulation (HTRF). The HTRF is then employed to carry out the free vibration analysis of doubly curved shallow and deep functionally graded material (FGM) shells. The PVD is further used in conjunction with the Gauss theorem to derive the governing differential equations and related natural boundary conditions. Donnell-Mushtari's shallow shell-type equations are given as a particular case. Doubly curved FGM shells and doubly curved sandwich shells made up of isotropic face sheets and FGM core are investigated. The proposed shell models are widely assessed by comparison with the literature results. Two benchmarks are provided and the effects of significant parameters such as stacking sequence, boundary conditions, length-to-thickness ratio, radius-to-length ratio and volume fraction index on the circular frequency parameters and modal displacements are discussed.

  12. Mutations induced in Tradescantia by small doses of X-rays and neutrons - Analysis of dose-response curves.

    NASA Technical Reports Server (NTRS)

    Sparrow, A. H.; Underbrink, A. G.; Rossi, H. H.

    1972-01-01

    Dose-response curves for pink somatic mutations in Tradescantia stamen hairs were analyzed after neutron and X-ray irradiation with doses ranging from a fraction of a rad to the region of saturation. The dose-effect relation for neutrons indicates a linear dependence from 0.01 to 8 rads; between 0.25 and 5 rads, a linear dependence is indicated for X-rays also. As a consequence the relative biological effectiveness reaches a constant value (about 50) at low doses. The observations are in good agreement with the predictions of the theory of dual radiation action and support its interpretation of the effects of radiation on higher organisms. The doubling dose of X-rays was found to be nearly 1 rad.

  13. Do Trajectories of At-Home Dementia Caregiving Account for Burden After Nursing Home Placement? A Growth Curve Analysis

    PubMed Central

    Newcomer, Robert; Gaugler, Joseph E.

    2010-01-01

    Transitioning to the nursing home setting is a complex process for family caregivers of older adults with dementia. While nursing home placement (NHP) can alleviate certain caregiving responsibilities, new stressors can also emerge. In the present study, the researchers examined how care-related factors can change leading up to NHP and how these factors influence caregiver outcomes following NHP. A sample of 634 family dementia caregivers (N = 634) were surveyed at three six-month intervals prior to NHP and once during the 12 month period following institutionalization. Growth curve modeling revealed dynamic changes in certain factors leading up to NHP (e.g., caregivers’ perceived health), while other factors remained stable (e.g., caregiver burden). Several factors emerged as significant predictors of caregiver burden following NHP, including pre-placement burden and adult day service utilization. For geriatric social workers, these findings may be useful in assessing family caregivers, and in the development and utilization of appropriate interventions. PMID:20853212

  14. Numerical analysis for MHD peristaltic transport of Carreau-Yasuda fluid in a curved channel with Hall effects

    NASA Astrophysics Data System (ADS)

    Abbasi, F. M.; Hayat, T.; Alsaedi, A.

    2015-05-01

    Impact of applied magnetic field on the peristaltic transport of Carreau-Yasuda fluid in a curved conduit is analyzed in this article. Hall effects are also taken into consideration. Lubrication approach is utilized in problem formulation. Resulting nonlinear system is solved numerically. Results for axial velocity, pressure gradient, pressure rise per wavelength and stream function are obtained and studied graphically. Results revealed that for small values of curvature parameter the fluid velocity is not symmetric about the centerline. Also increase in the value of Hall parameter balances the magnetic influence of applied magnetic field by some extent. Further, the Carreau-Yasuda fluid possesses large size of trapped bolus when compared with the Newtonian fluid.

  15. Pre-curving analysis of an opening crack in a magnetoelectroelastic strip under in-plane impact loadings

    NASA Astrophysics Data System (ADS)

    Hu, Keqiang; Chen, Zengtao

    2012-12-01

    An opening crack in a magnetoelectroelastic strip under in-plane mechanical, electric, and magnetic impact loadings is considered for magneto-electrically impermeable and permeable crack surface boundary conditions. Laplace and Fourier transforms are applied to reduce the mixed boundary value problem of the crack to dual integral equations, which are expressed in terms of Fredholm integral equations of the second kind. The asymptotic fields near the crack tip are obtained in explicit form and the corresponding field intensity factors are defined. The crack curving phenomena are investigated by applying the criterion of maximum hoop stress intensity factors. Numerical results show that the hoop stress intensity factors are influenced by the electric and magnetic loadings and the geometric size ratios.

  16. Missense Mutations in CRYAB Are Liable for Recessive Congenital Cataracts

    PubMed Central

    Irum, Bushra; Khan, Arif O.; Wang, Qiwei; Kabir, Firoz; Khan, Asma A.; Husnain, Tayyab; Akram, Javed; Riazuddin, Sheikh

    2015-01-01

    Purpose This study was initiated to identify causal mutations responsible for autosomal recessive congenital cataracts in consanguineous familial cases. Methods Affected individuals underwent a detailed ophthalmological and clinical examination, and slit-lamp photographs were ascertained for affected individuals who have not yet been operated for the removal of the cataractous lens. Blood samples were obtained, and genomic DNA was extracted from white blood cells. A genome-wide scan was completed with short tandem repeat (STR) markers, and the logarithm of odds (LOD) scores were calculated. Protein coding exons of CRYAB were sequenced, bi-directionally. Evolutionary conservation was investigated by aligning CRYAB orthologues, and the expression of Cryab in embryonic and postnatal mice lens was investigated with TaqMan probe. Results The clinical and ophthalmological examinations suggested that all affected individuals had nuclear cataracts. Genome-wide linkage analysis suggested a potential region on chromosome 11q23 harboring CRYAB. DNA sequencing identified a missense variation: c.34C>T (p.R12C) in CRYAB that segregated with the disease phenotype in the family. Subsequent interrogation of our entire cohort of familial cases identified a second familial case localized to chromosome 11q23 harboring a c.31C>T (p.R11C) mutation. In silico analyses suggested that the mutations identified in familial cases, p.R11C and p.R12C will not be tolerated by the three-dimensional structure of CRYAB. Real-time PCR analysis identified the expression of Cryab in mouse lens as early as embryonic day 15 (E15) that increased significantly until postnatal day 6 (P6) with steady level of expression thereafter. Conclusion Here, we report two novel missense mutations, p.R11C and p.R12C, in CRYAB associated with autosomal recessive congenital nuclear cataracts. PMID:26402864

  17. Did the Great Recession influence retirement plans?

    PubMed

    Szinovacz, Maximiliane E; Davey, Adam; Martin, Lauren

    2015-04-01

    The recent recession constitutes one of the macro forces that may have influenced workers' retirement plans. We evaluate a multilevel model that addresses the influence of macro-, meso-, and micro-level factors on retirement plans, changes in these plans, and expected retirement age. Using data from Waves 8 and 9 of the Health and Retirement Study (N=2,618), we find that individuals with defined benefit plans are more prone to change toward plans to stop work before the stock market declined, whereas the opposite trend holds for those without pensions. Debts, ability to reduce work hours, and firm unionization also influenced retirement plans. Findings suggest retirement planning education may be particularly important for workers without defined pensions, especially in times of economic volatility. PMID:25651572

  18. Intimate Partner Violence in the Great Recession.

    PubMed

    Schneider, Daniel; Harknett, Kristen; McLanahan, Sara

    2016-04-01

    In the United States, the Great Recession was marked by severe negative shocks to labor market conditions. In this study, we combine longitudinal data from the Fragile Families and Child Wellbeing Study with U.S. Bureau of Labor Statistics data on local area unemployment rates to examine the relationship between adverse labor market conditions and mothers' experiences of abusive behavior between 2001 and 2010. Unemployment and economic hardship at the household level were positively related to abusive behavior. Further, rapid increases in the unemployment rate increased men's controlling behavior toward romantic partners even after we adjust for unemployment and economic distress at the household level. We interpret these findings as demonstrating that the uncertainty and anticipatory anxiety that go along with sudden macroeconomic downturns have negative effects on relationship quality, above and beyond the effects of job loss and material hardship. PMID:27003136

  19. [The decline in population growth, income distribution, and economic recession].

    PubMed

    Banguero, H

    1983-05-01

    This work uses Keynesian principles and an analysis of the Colombian population in the 1970s to argue that the Colombian policy of slowing population growth, which was adopted with the aim of improving the general welfare of the population, has had shortterm negative effects on effective demand and thus on the level of employment and welfare. These negative effects were caused by the inflexibility of income distribution, which prevented expansion of the internal market, complicated by the stagnant condition of the external sector and the budget deficit. The results of the Colombian case study demonstrate how the deceleration of population growth beginning in the 1960s had a significant impact on the levels of consumption and savings and on the patterns of consumption, leading to low levels of investment and little dynamism. Although the current Colombian economic recession is aggravated by contextual factors such as the world economic recession, the high cost of capital, the industrial recession, and declining food production among others, at the core of the crisis are longer term structural determinants such as the decline in the rate of population growth and the highly unequal distribution of income and wealth, which have contributed to a shrinking of the internal market for some types of goods. Given the unlikelihood of renewed rapid population growth, the Keynesian model suggests that the only alternative for increasing aggregate demand is state intervention through public spending and investment and reorientation of the financial system to achieve a dynamic redistribution of income. Based on these findings and on proposals of other analysts, a stragegy for revitalization is proposed which would imply a gradual income redistribution to allow increased consumption of mass produced goods by the low income groups. Direct consumption subsidies would be avoided because of their inflationary and import-expanding tendencies; rather, incentives and support would be provided to 3 productive sectors: traditional agriculture, small factories producing mass consumption goods, and construction of low income housing. The strategy would promote economic growth and expansion without further deterioration of income distribution, employment, and price stability. A simulation study demonstrated the advantages of such a strategy in relation to alternative strategies. PMID:12266019

  20. Bluff evolution and long-term recession rates, southwestern Lake Michigan

    NASA Astrophysics Data System (ADS)

    Rovey, C. W.; Borucki, M. K.

    1994-06-01

    Where eroding cohesive sediments are present, Lake Michigan bluffs range up to 40 m in height, exposing multiple glacial stratigraphic units. Following the model presented here, bluffs form as a wave-cut terrace erodes inland from a point near the original shoreline. The erosion plane is nearly horizontal, in contrast with the eastward dip of the glacial units inherited from underlying bedrock. Therefore, terraces eroding inland produce progressively higher bluffs and expose successively older units at the toe and beneath the lake. This process was repeated several times as lake levels sequentially dropped to their modern stage. The initial modern shoreline, and hence the width of the wave-cut terrace, was determined from four offshore seismic and bottom-sampling profiles. It was picked as an inflection point in the lake bed, occurring offshore of dipping reflectors intersecting the lake bottom. The calculated average recession rate over a 2500-year duration of the modern stage is 1.5 m/yr in contrast to average rates of approximately 0.6 m/yr measured over the last century. Thus rates decrease through time as the terrace widens and wave energy is dampened. By correlating bluff height to recession distance, a third rate of approximately 2.7 m/yr for the first 940 years of recession is calculated from relict Nipissing bluffs. The three rates define a steeply decaying exponential curve in early stages of bluff retreat, flattening into a nearly linear function after 1000 years.

  1. Bluff formation and long-term recession rates, southwestern Lake Michigan

    SciTech Connect

    Rovey, C.W. II )

    1992-01-01

    Where eroding cohesive sediments are present, Lake Michigan bluffs range up to 140 ft. in height and expose multiple stratigraphic units. According to the model presented here, bluffs form as a wave cut terrace erodes inland from a point near the original shoreline. The erosion plane is nearly horizontal, in contrast with the eastward dip of the glacial units inherited from underlying bedrock. Therefore, terraces eroding inland (west) produce progressively higher bluffs and expose successively older units at the toe and beneath the lake. This process repeated several times as lake levels sequentially dropped to their modern stage. The initial modern shoreline, and hence the width of the wave cut terrace, was determined from 4 offshore seismic profiles. It is picked as an inflection point in the slope of the lake bed, occurring offshore of dipping reflectors intersecting the lake bottom. The calculated average recession rate over the 2,500 year duration of the modern stage is 5 ft/yr in contrast to average rates of 2 ft/yr measured over the last century. Thus rates decrease through time as the terrace widens and wave energy is damped. By correlating bluff height to amount of recession of modern bluffs, a third rate of 12 ft/yr of the first 800 years of a recession is calculated for relict bluffs formed at the Nipissing II level. The 3 rates define a steeply decaying exponential curve in early stages of bluff retreat, flattening into a nearly linear function after 1,000 years.

  2. Climatic Drivers of Tropical Andean Glacier Recession, c1987 - c2006

    NASA Astrophysics Data System (ADS)

    Slayback, D. A.; Tucker, C. J.

    2011-12-01

    We report on the climatic trends associated with glacier recession in the tropical Andes from the mid-1980s to the mid-2000s. These glaciers comprise 99% of the world's tropical glaciers and occur in Bolivia, Peru, Ecuador, Colombia, and Venezuela. We previously reported on our comprehensive analysis of Landsat imagery of these glaciers, which indicated an overall recession of approximately 30% in glacierized area between c1987 and c2006, or a drop from ~2500 km2 to ~1800 km2 in total glacier area. In the current work, we have examined trends in temperature, cloud cover, and precipitation and compared these trends with those in glacier recession. For temperature and cloud cover, we use the MERRA reanalysis datasets (Modern Era Retrospective-Analysis for Research and Applications) produced by the NASA Goddard's GMAO (Global Modeling and Assimilation Office), which are based on satellite observations. For precipitation, we use the GPCP (Glocal Precipitation Climatology Project) datasets, which are based on both ground and satellite observations. We find that over the glacierized zones, the only significant trends are those in temperature, which show increases of up to 0.5 degree C per decade over some glacierized areas. Trends in cloud cover and precipitation are not generally significant. We discuss these trends in relation to glacier recession trends for each of the major glacierized areas of the tropical Andes.

  3. Children's Recess Physical Activity: Movement Patterns and Preferences

    ERIC Educational Resources Information Center

    Woods, Amelia Mays; Graber, Kim C.; Daum, David Newman

    2012-01-01

    The benefits of recess can be reaped by all students regardless of socioeconomic status, race, or gender and at relatively little cost. The purpose of this study was to examine physical activity (PA) variables related to the recess PA patterns of third and fourth grade children and the social preferences and individuals influencing their PA…

  4. The Impact of the Recession on College Students

    ERIC Educational Resources Information Center

    Berg-Cross, Linda; Green, Rodney

    2010-01-01

    This article had three goals: (a) to provide a brief economic review of the relationship between recessionary times, institutional reactions, and the life trajectory of recession-era college students; (b) to discuss the recession-related psychosocial stressors facing today's college students; and (c) to discuss how counseling centers can help…

  5. Recess Physical Activity Packs in Elementary Schools: A Qualitative Investigation

    ERIC Educational Resources Information Center

    Elliott, Steven; Combs, Sue; Boyce, Robert

    2011-01-01

    To supplement the present weekly allotment of 30 minutes of physical education, a school district in southeastern North Carolina identified recess time as part of the state mandated (HSP-S-000) 150 minutes of physical activity (PA) per week and have purchased fitness equipment (recess packs) for the children to use. Twelve participants were…

  6. Parents' Victory in Reclaiming Recess for Their Children

    ERIC Educational Resources Information Center

    Zygmunt-Fillwalk, Eva; Bilello, Teresa Evanko

    2005-01-01

    This article discusses the issue of schools limiting the opportunities for children's physical, cognitive, social-emotional, and creative development that recess affords. Red Rover, hopscotch, jump rope, chase, telling secrets, hanging out, making friends, losing friends--these familiar pursuits of childhood recess are vividly memorable. While…

  7. The Fourth R: Recess and Its Link to Learning.

    ERIC Educational Resources Information Center

    Waite-Stupiansky, Sandra; Findlay, Marcia

    2001-01-01

    Review of research on recess shows how its presence or absence affects children's brain development, health and physical development, attention, memory, social and emotional adjustment, language development, and classroom behavior. Despite demonstrated benefits, recess is endangered by pressures on schools to increase achievement. (Contains 52

  8. Physical Education and Recess Contributions to Sixth Graders' Physical Activity

    ERIC Educational Resources Information Center

    Gutierrez, Ashley A.; Williams, Skip M.; Coleman, Margaret M.; Garrahy, Deborah A.; Laurson, Kelly R.

    2016-01-01

    Background: The purpose of this study was twofold: (a) to examine the percentage of the daily threshold (12,000 steps) that physical education (PE) class and recess contribute to 6th grade students' overall daily physical activity (PA) and (b) to examine the relationships between gender, PA outside of school, BMI, and steps during both recess and…

  9. Physical Education and Recess Contributions to Sixth Graders' Physical Activity

    ERIC Educational Resources Information Center

    Gutierrez, Ashley A.; Williams, Skip M.; Coleman, Margaret M.; Garrahy, Deborah A.; Laurson, Kelly R.

    2016-01-01

    Background: The purpose of this study was twofold: (a) to examine the percentage of the daily threshold (12,000 steps) that physical education (PE) class and recess contribute to 6th grade students' overall daily physical activity (PA) and (b) to examine the relationships between gender, PA outside of school, BMI, and steps during both recess and

  10. The Fourth R: Recess and Its Link to Learning.

    ERIC Educational Resources Information Center

    Waite-Stupiansky, Sandra; Findlay, Marcia

    2001-01-01

    Review of research on recess shows how its presence or absence affects children's brain development, health and physical development, attention, memory, social and emotional adjustment, language development, and classroom behavior. Despite demonstrated benefits, recess is endangered by pressures on schools to increase achievement. (Contains 52…

  11. Withholding Recess from Elementary School Students: Policies Matter

    ERIC Educational Resources Information Center

    Turner, Lindsey; Chriqui, Jamie F.; Chaloupka, Frank J.

    2013-01-01

    Background: Recess is a key aspect of a healthy elementary school environment and helps to keep students physically active during the school day. Although national organizations recommend that students not be withheld from recess, this practice occurs in schools. This study examined whether district policies were associated with school practices…

  12. DETAIL VIEW OF LOCK WALL RECESS AT THE DOWNSTREAM END ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW OF LOCK WALL RECESS AT THE DOWNSTREAM END OF LOCK 70. THE RECESS,TYPICAL OF BOTH WALLS IN ALL OF THE LOCKS, PROVIDED SPACE FOR OPEN LOCK GATES TO ALLOW UNIMPEDED PASSAGE OF LOCK TRAFFIC. - New York State Barge Canal, Lockport Locks, Richmond Avenue, Lockport, Niagara County, NY

  13. Genetic diversity of Dientamoeba fragilis isolates of irritable bowel syndrome patients by high-resolution melting-curve (HRM) analysis.

    PubMed

    Hussein, Eman M; Al-Mohammed, Hamdan I; Hussein, Abdalla M

    2009-10-01

    Dientamoeba fragilis is a parasite that has been recognized as a causative agent of gastrointestinal symptoms. The search for genetic variation in D. fragilis based on the small-subunit (SSU) rRNA gene using restriction fragment length polymorphism was found not useful for molecular epidemiology. In this study, genetic variability of different clinical isolates of D. fragilis was explored by high-resolution melting curve (HRM) following polymerase chain reaction (PCR) in a one-step closed-tube method. Thirty fecal samples from irritable bowel syndrome (IBS) patients having D. fragilis trophozoites and negative for other organisms were involved in this study. According to the type of diarrhea, eight patients had acute, 14 patients had chronic intermittent, and eight patients had diarrhea alternating with constipation. HRM proved that four profiles (subtypes) were present as detecting by scanning mutation. One of these profiles (profile 1) was predominant (50%). Profile 2 was present on 20%. Profiles 3 and 4 were present on 16.7% and 13.4%, respectively. No mixed profiles were detected among the samples. The melting curves characterized by T(m)1=77.17+/-0.29 degrees C in profile 1, T(m)1=77.37+/-1.45 degrees C in profile 2, T(m)1=74.24+/-0.08 degrees C and T(m)2=79.64+/-0.09 degrees C in profile 3, and T(m)1=75.51 +/- 0.09 degrees C and T(m)=79.42 +/- 0.09 degrees C in profile 4. The relation between these profiles and types of diarrhea proved that the majority of patients having profile 1 (73.4%) and profile 4 (75%) had chronic intermittent diarrhea. All of the patients having profile 2 had acute diarrhea while all of the patients having profile 3 had diarrhea alternating with constipation. Although profile 1 was detected among all types of diarrhea, it was corresponding to 11/14 of patients with chronic intermittent diarrhea. All the differences were clinically and statistically significant. In conclusion, HRM following PCR was proved as a wide variation on D. fragilis genotypes that could be related to the characters of diarrhea among IBS patients. As the differences in HRM reflect different sequences of SSU RNA gene, thus, another study for identifying the sequences of these isolates (profiles) will be done and published later. PMID:19543748

  14. Analytical solutions for recession analyses of sloping aquifers in alpine catchments

    NASA Astrophysics Data System (ADS)

    Pauritsch, Marcus; Hergarten, Stefan; Winkler, Gerfried; Birk, Steffen

    2015-04-01

    Analytical solutions for the discharge recession of sloping aquifers are commonly used to simulate the runoff of shallow aquifers with slope angles of a few degrees and in particular hillslopes. However, in alpine catchments, potentially deeper aquifers represented by debris accumulations such as relict rock glaciers can be found in areas with much steeper slope angles. These aquifers might be important for flood reduction and drought prevention and the discharged water can be used for drinking water supply and small hydroelectric power plants. Here it is attempted to reproduce the recession behavior of such highly inclined aquifers by applying existing analytical solutions for sloping aquifers. More specifically, an analytical solution for the discharge recession of a sloping aquifer is compared to a numerical model (MODFLOW) for a variety of slope angles. In addition a sensitivity analysis is made to reveal the effects of the various approximations introduced in the analytical solution, such as homogeneity, parallel side boundaries and a straight profile. The results show that the deviation between the analytical solution and the numerical model depends on the hydraulic properties and is in general acceptable for all tested slope angles. However, the sensitivity analysis shows that the simplifying assumptions and especially the initial condition have great impact on the discharge recession. Therefore, only the long-term behavior of the analytical solution should be considered if the model is employed for aquifer characterization. In summary, the combined use of analytical solutions and simple numerical models helps to better understand the opportunities and limitations of the recession analysis of sloping aquifers.

  15. A master curve analysis of F82H using statistical and constraint loss size adjustments of small specimen data

    NASA Astrophysics Data System (ADS)

    Odette, G. R.; Yamamoto, T.; Kishimoto, H.; Sokolov, M.; Spätig, P.; Yang, W. J.; Rensman, J.-W.; Lucas, G. E.

    2004-08-01

    We assembled a fracture toughness database for the IEA heat of F82H based on a variety of specimen sizes with a nominal ASTM E1921 master curve (MC) reference temperature T0=-119±3 °C. However, the data are not well represented by a MC. T0 decreases systematically with a decreasing deformation limit Mlim starting at ≈200, which is much higher than the E1921 censoring limit of 30, indicating large constraint loss in small specimens. The small scale yielding T0 at high Mlim is ≈98±5 °C. While, the scatter was somewhat larger than predicted, after model-based adjustments for the effects of constraint loss, the data are in reasonably good agreement with a MC with T0=-98 °C. This supports to use of MC methods to characterize irradiation embrittlement, as long as both constraint loss and statistical size effects are properly accounted for. Finally, we note various issues, including sources of the possible excess scatter, which remain to be fully assessed.

  16. Robust Spatial Approximation of Laser Scanner Point Clouds by Means of Free-form Curve Approaches in Deformation Analysis

    NASA Astrophysics Data System (ADS)

    Bureick, Johannes; Alkhatib, Hamza; Neumann, Ingo

    2016-03-01

    In many geodetic engineering applications it is necessary to solve the problem of describing a measured data point cloud, measured, e. g. by laser scanner, by means of free-form curves or surfaces, e. g., with B-Splines as basis functions. The state of the art approaches to determine B-Splines yields results which are seriously manipulated by the occurrence of data gaps and outliers. Optimal and robust B-Spline fitting depend, however, on optimal selection of the knot vector. Hence we combine in our approach Monte-Carlo methods and the location and curvature of the measured data in order to determine the knot vector of the B-Spline in such a way that no oscillating effects at the edges of data gaps occur. We introduce an optimized approach based on computed weights by means of resampling techniques. In order to minimize the effect of outliers, we apply robust M-estimators for the estimation of control points. The above mentioned approach will be applied to a multi-sensor system based on kinematic terrestrial laserscanning in the field of rail track inspection.

  17. Growth Curve Models for the Analysis of Phenotype Arrays for a Systems Biology Overview of Yersinia pestis

    SciTech Connect

    Fodor, I K; Holtz-Morris, A E; McCutchen-Maloney, S L

    2005-09-08

    The Phenotype MicroArray technology of Biolog, Inc. (Hayward, CA) measures the respiration of cells as a function of time in thousands of microwells simultaneously, and thus provides a high-throughput means of studying cellular phenotypes. The microwells contain compounds involved in a number of biochemical pathways, as well as chemicals that test the sensitivity of cells against antibiotics and stress. While the PM experimental workflow is completely automated, statistical methods to analyze and interpret the data are lagging behind. To take full advantage of the technology, it is essential to develop efficient analytical methods to quantify the information in the complex datasets resulting from PM experiments. We propose the use of statistical growth-curve models to rigorously quantify observed differences in PM experiments, in the context of the growth and metabolism of Yersinia pestis cells grown under different physiological conditions. The information from PM experiments complement genomic and proteomic results and can be used to identify gene function and in drug development. Successful coupling of phenomics results with genomics and proteomics will lead to an unprecedented ability to characterize bacterial function at a systems biology level.

  18. Analysis of first order reversal curves in the thermal hysteresis of spin-crossover nanoparticles within the mechanoelastic model

    SciTech Connect

    Stoleriu, Laurentiu E-mail: cristian.enachescu@uaic.ro; Stancu, Alexandru; Enachescu, Cristian E-mail: cristian.enachescu@uaic.ro; Chakraborty, Pradip; Hauser, Andreas

    2015-05-07

    The recently obtained spin-crossover nanoparticles are possible candidates for applications in the recording media industry as materials for data storage, or as pressure and temperature sensors. For these applications, the intermolecular interactions and interactions between spin-crossover nanoparticles are extremely important, as they may be essential factors in triggering the transition between the two stable phases: the high-spin and low-spin ones. In order to find correlations between the distributions in size and interactions and the transition temperatures distribution, we apply the FORC (First Order Reversal Curves) method, using simulations based on a mechanoelastic model applied to 2D triangular lattices composed of molecules linked by springs and embedded in a surfactant. We consider two Gaussian distributions: one is the size of the nanoparticles and another is the elastic interactions between edge spin-crossover molecules and the surfactant molecules. In order to disentangle the kinetic and non-kinetic parts of the FORC distributions, we compare the results obtained for different temperature sweeping rates. We also show that the presence of few larger particles in a distribution centered around much smaller particles dramatically increases the hysteresis width.

  19. Design, analysis, and fabrication of a pressure box test fixture for tension damage tolerance testing of curved fuselage panels

    NASA Technical Reports Server (NTRS)

    Smith, P. J.; Bodine, J. B.; Preuss, C. H.; Koch, W. J.

    1993-01-01

    A pressure box test fixture was designed and fabricated to evaluate the effects of internal pressure, biaxial tension loads, curvature, and damage on the fracture response of composite fuselage structure. Previous work in composite fuselage tension damage tolerance, performed during NASA contract NAS1-17740, evaluated the above effects on unstiffened panels only. This work extends the tension damage tolerance testing to curved stiffened fuselage crown structure that contains longitudinal stringers and circumferential frame elements. The pressure box fixture was designed to apply internal pressure up to 20 psi, and axial tension loads up to 5000 lb/in, either separately or simultaneously. A NASTRAN finite element model of the pressure box fixture and composite stiffened panel was used to help design the test fixture, and was compared to a finite element model of a full composite stiffened fuselage shell. This was done to ensure that the test panel was loaded in a similar way to a panel in the full fuselage shell, and that the fixture and its attachment plates did not adversely affect the panel.

  20. Prediction of landslide velocity at given cumulated rainfall values based on analysis of continuous monitoring data using ROC curves: application to the Piagneto landslide (Northern Apennine, Italy)

    NASA Astrophysics Data System (ADS)

    Corsini, Alessandro; Mulas, Marco; Petitta, Marcello; Bonacini, Francesco; Ronchetti, Francesco; Caputo, Giuseppe; Truffelli, Giovanni

    2015-04-01

    A novel approach to predict landslide velocity at given cumulated rainfall values based on the analysis of continuous displacement and rainfall monitoring data by using ROC curves has been developed and tested in the Piagneto landslide (northern Apennines, Italy). It is an active rock slide for which a velocity dataset covering the period October 2009 to December 2014 is available thanks to a total station that has been monitoring tens of prisms at duty cycles of 2 hours. Over the same time frame, an hourly rainfall dataset is available from rain gauges located just a few km away from the landslide. The ROC curve (Receiver Operating Characteristic) is a well-known and widely used method to assess the efficiency of a binary classifier. In this case, it is used to assess the efficiency of different values of cumulated rainfall to determine a given value of velocity in the landslide. Operatively, the daily velocity distributions of selected monitoring prisms is plotted in order to assess upper values at given levels of occurrence probability, i.e. velocity values at the upper 1st,2nd, 3rd quartile and 2 sigma. These velocity values are then classified with respect to daily rainfall cumulated over different time windows (from 1 to 120 days), that are considered singularly or in combination one another. The area under the ROC curves, as well as the max distance from the random line, is used as indicator of performance in order to assess the cumulated rainfall (in terms of amount and duration) showing the higher performance in predicting a defined landslide velocity level. The values obtained with the retrospective analysis of monitoring data, can then be used for prediction of expected velocity levels. This has been verified by using the conventional approach of dividing the dataset in a training and a validation subsets. Results underline the added value of the analysis of long time-series of continuous landslide monitoring data by mean of operational research tools, such as in this case the ROC curves, for extracting information useful for improving the comprehension and the prediction of slope dynamics that, in specific cases, can be of great support to risk management.