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1

Recession curve analysis for groundwater levels: case study in Latvia  

NASA Astrophysics Data System (ADS)

Recession curve analysis is powerful and effective analysis technique in many research areas related with hydrogeology where observations have to be made, such as water filtration and absorption of moisture, irrigation and drainage, planning of hydroelectric power production and chemical leaching (elution of chemical substances) as well as in other areas. The analysis of the surface runoff hydrograph`s recession curves, which is performed to conceive the after-effects of interaction of precipitation and surface runoff, has approved in practice. The same method for analysis of hydrograph`s recession curves can be applied for the observations of the groundwater levels. There are manually prepared hydrograph for analysis of recession curves for observation wells (MG2, BG2 and AG1) in agricultural monitoring sites in Latvia. Within this study from the available monitoring data of groundwater levels were extracted data of declining periods, splitted by month. The drop-down curves were manually (by changing the date) moved together, until to find the best match, thereby obtaining monthly drop-down curves, representing each month separately. Monthly curves were combined and manually joined, for obtaining characterizing drop-down curves of the year for each well. Within the process of decreased recession curve analysis, from the initial curve was cut out upward areas, leaving only the drops of the curve, consequently, the curve is transformed more closely to the groundwater flow, trying to take out the impact of rain or drought periods from the curve. Respectively, the drop-down curve is part of the data, collected with hydrograph, where data with the discharge dominates, without considering impact of precipitation. Using the recession curve analysis theory, ready tool "A Visual Basic Spreadsheet Macro for Recession Curve Analysis" was used for selection of data and logarithmic functions matching (K. Posavec et.al., GROUND WATER 44, no. 5: 764-767, 2006), as well as functions were developed by manual processing of data. For displaying data the mathematical model of data equalization was used, finding the corresponding or closest logarithmic function of the recession for the graph. Obtained recession curves were similar but not identical. With full knowledge of the fluctuations of ground water level, it is possible to indirectly (without taking soil samples) determine the filtration coefficient: more rapid decline in the recession curve correspond for the better filtration conditions. This research could be very useful in construction planning, road constructions, agriculture etc. Acknowledgments The authors gratefully acknowledge the funding from ESF Project "Establishment of interdisciplinary scientist group and modeling system for groundwater research" (Agreement No. 2009/0212/1DP/1.1.1.2.0/09/APIA/VIAA/060EF7)

Gailuma, A.; VÄ«tola, I.; Abramenko, K.; Lauva, D.; Vircavs, V.; Veinbergs, A.; Dimanta, Z.

2012-04-01

2

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

NASA Astrophysics Data System (ADS)

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.

Ye, Sheng; Li, Hong-Yi; Huang, Maoyi; Ali, Melkamu; Leng, Guoyong; Leung, L. Ruby; Wang, Shao-wen; Sivapalan, Murugesu

2014-11-01

3

Stream recession curves and storage variability in small watersheds  

NASA Astrophysics Data System (ADS)

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, there have been few systematic assessments of how streamflow recession varies across flow rates and how it relates 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 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-1) to 10 days at low flow rates (~0.01 mm h-1), leveling off at low flow rates. There is significant variability in the recession timescale at a given flow rate between basins, which correlates 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 inferred storage shows similar time evolution to regional-scale water storage variability estimated from GRACE satellite gravity data and from land surface modeling forced by observed meteorology, but is up to a factor of 10 smaller. Study of this discrepancy in the inferred storage amplitude may provide clues to the range of validity of the recession curve approach to relating runoff and storage.

Krakauer, N. Y.; Temimi, M.

2011-07-01

4

Estimation of recession curve of karst spring hydrograph: example of the spring Gradole  

NASA Astrophysics Data System (ADS)

The spring Gradole represents a typical karst spring of the rising type, which is situated in central part of Istria (Croatia). The drainage area is composed mostly of carbonate rocks (limestone) and partly of flysch components (marls and sandstones). The average altitude of the catchment area is approximately 330 m a.s.l. Strong tectonic deformations have made carbonate deposits very permeable, enabling the infiltration of water. The average rainfall is between 1046 and 1120 mm. The catchment area of the spring is estimated to approximately 114 km2. Several studies have shown that the recession curves of karst spring hydrographs characterize the storage properties of karst aquifers. The change in slope can be explained with the drainage of different types of media typical for karst, such as conduits, fractures, pores and fissures. The main factors that affect the recession curve are aquifer lithology and geometry of conduits. Consequently, the recession curve analyzes can provide information about the aquifer and the main features of karst rock massif. Usually, the recession curves can be fitted well by the function that consists of two or more exponential terms with exponential coefficients ?1,?2,…, where the lower coefficient ?1 represents the slow flow through porous medium or base flow. The recession curve that represents base flow is usually named as the master recession curve and its exponential coefficient ?1 is named as the master recession coefficient. In this study, classical methods for estimation of recession curve are applied to the hydrograph of the spring Gradole. The results are compared with those obtained by applying Composite Transfer Functions (CTF). Differently from classical parametric and nonparametric transfer functions that represent the quick flow and base flow component of spring response by a single function, CTF represents the spring response by two functions adapted for the quick flow and the slow flow component. The quick flow component is represented by a nonparametric transfer function, whereas the slow flow component is represented by a parametric transfer function which is an Instantaneous Unit Hydrograph (IUH) formulated and defined mathematically from a conceptual model. By using CTF for Rainfall-Runoff (RR) modeling, the simulations of long recession periods as well as the simulations of complete hydrograph become more successful. If IUH defined from the conceptual model of linear reservoir is applied, the parametric transfer function representing slow flow component has exponential form. It means that the recession coefficient of IUH represents the master recession coefficient of the spring hydrograph, i.e. the recession coefficient of IUH can be determined by using classical methods for the estimation of master recession coefficient, and vice versa, the problem of determination of master recession coefficient can be transformed to the problem of determination of the recession coefficient of IUH. The recession coefficient of IUH is determined simultaneously with the values of nonparametric transfer function in the optimization procedure for estimation of parameters of RR model based on CTF. The recession coefficients of IUH are obtained separately in the optimization procedures for each hydrological year during the period 1987-2002. The results show that the recession curve of the spring Gradole has not a unique form. Depending on hydrological year, the obtained nonparametric transfer functions representing quick flow component can be fitted by one or two exponential terms. The values of master recession coefficient vary between 100 and 260 days. The average value for the entire period of 15 years is 140 days. These results are similar to the results obtained by applying classical methods for estimation of master recession curve. It confirms practically that the recession coefficient of IUH can be estimated from the spring hydrograph, which can be useful for RR modeling based on CTF because the number of unknown parameters is reduced.

Deni?-Juki?, V.; Kuštera, K.; Juki?, D.

2009-04-01

5

Stream recession curves and storage variability in small watersheds  

NASA Astrophysics Data System (ADS)

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.

Krakauer, N. Y.; Temimi, M.

2011-02-01

6

Recession, S-curves and Digital Equipment Corporation  

E-print Network

it conformed to this model in the first thirty years but missed out on the disruptive technology of PCs. Their growth can be linked to disruptive technology, the `S-curve' and also to the world's financial `wave to disappear completely. This paper looks at DEC both in relation to the S-curve of technology and how

Paris-Sud XI, Université de

7

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

NASA Technical Reports Server (NTRS)

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.

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

2002-01-01

8

Geomorphic Signatures on Brutsaert Base Flow Recession Analysis: case study of 27 Swiss Catchments  

NASA Astrophysics Data System (ADS)

Recession flow analysis are crucial in many areas of water resource management and useful to forecast base flow in gauged rivers. Moving from a classical recession curve analysis method, a large set of recession curves has been analyzed from Swiss streamflow data of 27 watersheds. For these catchments, digital elevation models have been precisely analyzed and a method aimed at the geomorphic origins of recession curves has been applied to the Swiss dataset. The method links river network morphology, epitomized by time-varying distribution of contributing channel sites, with the classic parametrization of recession events. This is done by assimilating two scaling exponents, ? and bG, with |dQ/dt|?Q? where Q is at-a-station gauged flow rate and N(l)?G(l)bG where l is the downstream distance from the channel heads receding in time at constant speed c, N(l) is the number of draining channel reaches located at distance l from their heads, and G(l) is the total drainage network length at a distance greater or equal to l. We find that the method provides good results in catchments where drainage density can be regarded as spatially constant. We propose several corrections to the method accounting for arbitrary local drainage densities affecting the local drainage inflow per unit channel length. In particular, we relax the assumption of uniform constant speed c. Such corrections properly vanish when the local drainage density become spatially constant. Overall, definite geomorphic signatures are recognizable for recession curves. In general, we suggest that this conceptual model might be useful to estimate the low flow regime of natural ungauged basins by predicting its features solely from information remotely acquired and objectively manipulated through DEM data.

Mutzner, R.; Bertuzzo, E.; Tarolli, P.; Weijs, S. V.; Nicotina, L.; Ceola, S.; Tomasic, N.; Rodriguez-Iturbe, I.; Parlange, M. B.; Rinaldo, A.

2013-12-01

9

A computer program for predicting recharge with a master recession curve  

USGS Publications Warehouse

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.

Heppner, Christopher S.; Nimmo, John R.

2005-01-01

10

Using Hydrograph Recession Analysis for Linking Hydrology to Chemistry: A Flow Regime Approach  

NASA Astrophysics Data System (ADS)

Hydrograph recession analysis is of great utility for the interpretation of water quality data, particularly when examining the hydrological processes responsible for runoff generation and impacts of changing land use on water quality. The theoretical basis for hydrograph recession analysis is well known, however the technique has traditionally been under-utilized for studies in which water quality is linked to runoff. Here, a 3-step approach is outlined for such investigations. First, long-term flow recessions are compiled in order to construct a Master Recession Curve (MRC) at a particular point of discharge (e.g., a stream reach, spring, or weir), taking any major seasonal effects into account. Second, the MRC is subsequently divided into flow regimes (from peak flow to baseflow) based upon changes in the recession coefficients that arise from the hydrograph recession analysis. Finally, observed chemical data that fall within the identified flow regimes are statistically described and reduced through principle components analysis (PCA) or other means, allowing for more focused interpretation of water quality variability and prediction according to flow conditions. Characterization of the flow regimes is the crucial link between discharge and water quality for it grants the hydrologist the ability to look for patterns and trends within a reduced set of flow-dependent water quality variables. In conjunction with an end-member mixing model that utilizes solute and isotope tracer data, hydrograph separation and end-member mixing analysis (EMMA) can be performed individually on the identified flow regimes. This approach can provide quantitative information about contributions to discharge derived from chemically distinct water sources in accordance with the flow regimes of the system. Examples from a forested headwater watershed and spring flow from a karst region are presented.

Doctor, D. H.

2003-12-01

11

Recession analysis of the Hupselse Beek catchment, The Netherlands  

NASA Astrophysics Data System (ADS)

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

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

2009-04-01

12

Hydromorphologic Recession Analysis: Accounting for Human Influences in Watershed Behaviors  

NASA Astrophysics Data System (ADS)

Integrated management of ground and surface waters has generally relied on baseflow characterization to understand the temporal variability in the contribution of watershed storage to streamflow. Recent research, however, indicates that small disturbances attributed to humans can impact our ability to characterize baseflow behaviors. In this study, we present an approach to account for human impacts on the estimation of baseflow recession parameters in California's Central Valley. The framework assesses how baseflow characterization is impacted by the combination of groundwater abstractions and surface water management strategies used to meet both residential and agricultural water demands. The results highlight the importance of accounting for human influences to characterize watershed properties by evaluating traditional (i.e. natural) and human-corrected recession parameters. Such results can influence studies ranging from water resources management to stream restoration projects that rely on accurate accounting of baseflow, especially during low flows.

Thomas, B. F.; Famiglietti, J. S.

2013-12-01

13

Autosomal recessive  

MedlinePLUS

Genetics - autosomal recessive; Inheritance - autosomal recessive ... an autosomal disorder. Genes come in pairs. Recessive inheritance means ... OF INHERITING A TRAIT If you are born to parents who both ...

14

Conformational analysis of nucleic acids revisited: Curves+  

Microsoft Academic Search

We describe Curves+, a new nucleic acid confor- mational analysis program which is applicable to a wide range of nucleic acid structures, including those with up to four strands and with either canon- ical or modified bases and backbones. The program is algorithmically simpler and computationally much faster than the earlier Curves approach, although it still provides both helical and

R. Lavery; M. Moakher; J. H. Maddocks; D. Petkeviciute; K. Zakrzewska

2009-01-01

15

Wavelet Analysis of Galactic Rotation Curves  

E-print Network

The spatial wavelet spectra of 73 published spiral galaxies's rotation curves are computed and their associated scaleograms are presented. Scaleograms are used to detect and isolate local features observed in spiral galaxies's rotation curves. Although wiggles and bumps are usually interpreted as signs of recent and on-going merging, the analysis of the scaleograms reveals regular patterns consistent with the presence of large-scale modes throughout the disk.

M. Kuassivi

2011-04-28

16

MEASURING INTERPHASE RECESSION BY FIBER PUSH-IN TESTING  

SciTech Connect

A novel technique for measuring interphase recession in ceramic matrix composites (CMCs) due to oxidation is described. The technique involves fiber push-in testing and analysis of the load-displacement curves. Fiber push-in tests are conducted on carbon-coated Hi-Nicalon SiC fibers in a CVI SiC matrix, where the carbon interphase had recessed due to oxidation. Estimates of interphase recession distances from analysis of fiber push-in tests are in reasonable agreement with measurements made by optical microscopy. Besides measuring the recession distance, the fiber push-in test can be used to investigate environmental effects on fiber bridging.

Lewinsohn, Charles A.; Henager, Charles H.; Jones, Russell H.; Eldridge, Jeffrey I.

2001-04-01

17

Conformational analysis of nucleic acids revisited: Curves+.  

PubMed

We describe Curves+, a new nucleic acid conformational analysis program which is applicable to a wide range of nucleic acid structures, including those with up to four strands and with either canonical or modified bases and backbones. The program is algorithmically simpler and computationally much faster than the earlier Curves approach, although it still provides both helical and backbone parameters, including a curvilinear axis and parameters relating the position of the bases to this axis. It additionally provides a full analysis of groove widths and depths. Curves+ can also be used to analyse molecular dynamics trajectories. With the help of the accompanying program Canal, it is possible to produce a variety of graphical output including parameter variations along a given structure and time series or histograms of parameter variations during dynamics. PMID:19625494

Lavery, R; Moakher, M; Maddocks, J H; Petkeviciute, D; Zakrzewska, K

2009-09-01

18

Conformational analysis of nucleic acids revisited: Curves+  

PubMed Central

We describe Curves+, a new nucleic acid conformational analysis program which is applicable to a wide range of nucleic acid structures, including those with up to four strands and with either canonical or modified bases and backbones. The program is algorithmically simpler and computationally much faster than the earlier Curves approach, although it still provides both helical and backbone parameters, including a curvilinear axis and parameters relating the position of the bases to this axis. It additionally provides a full analysis of groove widths and depths. Curves+ can also be used to analyse molecular dynamics trajectories. With the help of the accompanying program Canal, it is possible to produce a variety of graphical output including parameter variations along a given structure and time series or histograms of parameter variations during dynamics. PMID:19625494

Lavery, R.; Moakher, M.; Maddocks, J. H.; Petkeviciute, D.; Zakrzewska, K.

2009-01-01

19

Analysis of geometries with closed timelike curves  

NASA Astrophysics Data System (ADS)

This work deals with the analysis of cylindrically symmetric and stationary space-times mathcal{C}_{t} with closed timelike curves. The equation of motion describing the evolution of a massive scalar field in a mathcal{C}_{t} space-time is obtained. A class of space-times with closed timelike curves describing cosmic strings and cylinders is studied in detail. In such space-times, both massive particles as well as photons can reach the non-causal region. Geodesics and closed timelike curves are calculated and investigated. We have observed that massive particles and photons describe, essentially, two kinds of trajectories: confined orbits and scattering states. The analysis of the light cones show us clearly the intersection between future and past inside the non-causal region. Exact solutions for the equation of motion of massive scalar field propagating in cosmic strings and cylinder space-times are presented. Quasinormal modes for the scalar field have been calculated in static and rotating cosmic cylinders. We found unstable modes in the rotating cases. Rotating as well as static cosmic strings, i.e., without regular interior solutions, do not display quasinormal modes for the scalar field. We conclude presenting a conjecture relating closed timelike curves and space-time instability.

Pavan, A. B.

2010-05-01

20

Incorporating Experience Curves in Appliance Standards Analysis  

SciTech Connect

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.

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

21

Similarity Analysis between near surface soil moisture and streamflow during recession events in an alpine catchment  

NASA Astrophysics Data System (ADS)

Spatial and temporal variability of near surface soil moisture is important for understanding streamflow generation in high altitude mountain catchments since antecedent soil moisture plays an important role in the timing of runoff. For relatively small to medium sized catchments, the spatial variability of near surface soil moisture is hard to capture with remote sensing techniques and distributed point measurements are needed. Linking local measurements of soil moisture with integrating catchment scale streamflow measurements remains a great challenge in hydrological modeling. Since 2008, an alpine watershed of 20.4 km2 has been intensively monitored in the Swiss Alps, with a deployment of a network of wireless meteorological stations, measuring soil moisture along with other meteorological forcings. The discharge is monitored at three different sites. We present some preliminary results from a statistical analysis linking the spatial variation of the soil moisture, measured at 20 and 40 cm, with the variation of the streamflow in the particular case of recession events. A classic parameterization of recession events relating the variation of the discharge dQ-dt to the discharge Q by |dQ-dt|? Q? is used and transposed to soil moisture data. The parameterized soil moisture variation is then partitioned into runoff and evapotranspiration leading to better knowledge of local processes at the hillslope scale.

Mutzner, Raphael; Weijs, Steven V.; Rinaldo, Andrea; Parlange, Marc B.

2013-04-01

22

Sampling Planar Curves Using Curvature-Based Shape Analysis  

E-print Network

represented as NURBs (non-uniform rational B-spline, e.g. [4, 8]). The problem of curve shape analysis has to separate different levels of details. Multiresolution de- composition of B-spline curves is studied in [9Sampling Planar Curves Using Curvature-Based Shape Analysis Tatiana Surazhsky Vitaly Surazhsky

Surazhsky, Vitaly

23

Analysis of exoplanetary transit light curves  

E-print Network

This Thesis considers the scenario in which an extra-solar planet (exoplanet) passes in front of its star relative to our observing perspective. In this event, the light curve measured for the host star features a systematic ...

Carter, Joshua Adam

2009-01-01

24

Whole Exome Analysis Identifies Frequent CNGA1 Mutations in Japanese Population with Autosomal Recessive Retinitis Pigmentosa  

PubMed Central

Objective The purpose of this study was to investigate frequent disease-causing gene mutations in autosomal recessive retinitis pigmentosa (arRP) in the Japanese population. Methods In total, 99 Japanese patients with non-syndromic and unrelated arRP or sporadic RP (spRP) were recruited in this study and ophthalmic examinations were conducted for the diagnosis of RP. Among these patients, whole exome sequencing analysis of 30 RP patients and direct sequencing screening of all CNGA1 exons of the other 69 RP patients were performed. Results Whole exome sequencing of 30 arRP/spRP patients identified disease-causing gene mutations of CNGA1 (four patients), EYS (three patients) and SAG (one patient) in eight patients and potential disease-causing gene variants of USH2A (two patients), EYS (one patient), TULP1 (one patient) and C2orf71 (one patient) in five patients. Screening of an additional 69 arRP/spRP patients for the CNGA1 gene mutation revealed one patient with a homozygous mutation. Conclusions This is the first identification of CNGA1 mutations in arRP Japanese patients. The frequency of CNGA1 gene mutation was 5.1% (5/99 patients). CNGA1 mutations are one of the most frequent arRP-causing mutations in Japanese patients. PMID:25268133

Katagiri, Satoshi; Akahori, Masakazu; Sergeev, Yuri; Yoshitake, Kazutoshi; Ikeo, Kazuho; Furuno, Masaaki; Hayashi, Takaaki; Kondo, Mineo; Ueno, Shinji; Tsunoda, Kazushige; Shinoda, Kei; Kuniyoshi, Kazuki; Tsurusaki, Yohinori; Matsumoto, Naomichi; Tsuneoka, Hiroshi; Iwata, Takeshi

2014-01-01

25

Curve analysis of the aging orbital aperture.  

PubMed

It was hypothesized that skeletal aging results in curve distortion of the orbital aperture. Data were compiled from a cross-sectional study of the Robert J. Terry human skull collection at the Smithsonian Institution, Washington, D.C. Statistical analyses suggest that postadult differential growth results in progressive distortion of the orbital aperture. These changes may have both cosmetic and functional consequences. PMID:11818864

Pessa, Joel E; Chen, Yuan

2002-02-01

26

Concession Curve Analysis for Inspire Negotiations  

Microsoft Academic Search

In the course of a negotiation it is often the case that the participants exchange packages of offers, which have, at least\\u000a in the mind of the negotiators, a certain utility for them. We want to test whether the behaviour of the negotiators is reflected\\u000a in the topology of the concession curve that plots each offer's utility value in the

Vivi Nastase

2006-01-01

27

Delamination Analysis Of Composite Curved Bars  

NASA Technical Reports Server (NTRS)

Classical anisotropic elasticity theory used to construct "multilayer" composite semicircular curved bar subjected to end forces and end moments. Radial location and intensity of open-mode delamination stress calculated and compared with results obtained from anisotropic continuum theory and from finite element method. Multilayer theory gave more accurate predictions of location and intensity of open-mode delamination stress. Currently being applied to predict open-mode delamination stress concentrations in horse-shoe-shaped composite test coupons.

Ko, William L.; Jackson, Raymond H.

1990-01-01

28

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

SciTech Connect

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.

Beier, D.R.; Dushkin, H.; Tobin, D. [Harvard Medical School, Boston, MA (United States)] [and others

1994-09-01

29

Growth curve analysis of Rambouillet ewes  

E-print Network

). Specific age~eight models for analyzing growth curves exist (Gompertz [Winsor, 1932]; Brody, 1945; von Bertslanffy, 1957; Richards, 1959; logistic [Nelder, 1961]). Their specific attributes and limitations have been thoroughly reviewed (Seebeck, 1968... be expressed as: I d I t2 tl A dt A t2 tl The change in size over time ~ which is absolute growth rate (AGR) dv dt can be estimated by, yt AGR =~ dt t2 ? tl When y refers to the body weight and t to the age in days, AGR is often called average daily...

Mathenge, James Mwai

2012-06-07

30

Curving Analysis of Modified Designs of Passenger Railway Vehicle Trucks  

Microsoft Academic Search

In this paper, modified truck designs were studied with an objective to achieving better compatibility between high speed stability and curving behaviour compared to the conventional truck. The analysis has shown that USD truck can be designed to achieve better over all performance compared to other truck designs. The results of steady state curving program were validated using the commercial

Rao V. Dukkipati; Srinivasan Narayanaswamy; Mohammad O. M. Osman

2002-01-01

31

Applied Budyko curve analysis for county level water resources management  

NASA Astrophysics Data System (ADS)

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.

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

2010-12-01

32

Principal-component analysis of RR Lyrae light curves  

NASA Astrophysics Data System (ADS)

In this paper, we analyse the structure of RRab starlight curves using principal-component analysis. We find this to be a very efficient way of describing many aspects of RRab light-curve structure: in many cases, a principal-component fit with nine parameters can describe a RRab light curve including bumps, whereas a 17-parameter Fourier fit is needed. Consequently, we show statistically why the amplitude is also a good summary of the structure of these RR Lyrae light curves. We also use our analysis to derive an empirical relation relating absolute magnitude to light-curve structure. In comparing this formula with those derived from exactly the same data set but using Fourier parameters, we find that the principal-component analysis approach has distinct advantages. These advantages are, firstly, that the errors on the coefficients multiplying the fitted parameters in such formulae are much smaller, and secondly, that the correlation between the principal components is significantly smaller than the correlation between Fourier amplitudes. These two factors lead to reduced formal errors, in some cases estimated to be a factor of 2, on the eventual fitted value of the absolute magnitude. This technique will prove very useful in the analysis of data from existing and new large-scale survey projects concerning variable stars.

Kanbur, S. M.; Mariani, H.

2004-12-01

33

School Recess and Group Classroom Behavior  

Microsoft Academic Search

OBJECTIVES. This study examines the amount of recess that children 8 to 9 years of age receive in the United States and compares the group classroom behavior of children receiving daily recess with that of children not receiving daily recess. METHODS. This is a secondary analysis of a public-use data set, the Early Childhood Longitudinal Study, Kindergarten Class of 1998

Romina M. Barros; Ellen J. Silver; Ruth E. K. Stein

2009-01-01

34

Analysis of meteorology adjusted sulfate trend and the implication of recent recession impact  

NASA Astrophysics Data System (ADS)

Observed sulfate aerosols are mainly produced from the oxidation of sulfur dioxide (SO2) in the atmosphere. Most of the SO2 emissions, however, result from fossil fuel burning. For this reason, most of the aerosol produced from the oxidation of SO2 is considered to be from anthropogenic origins. Significant drops in the observed sulfate concentrations in 2008-2009 nationwide draw an interest to examine what may be the major driving forces behind this unusual event. In this study, 2002-2009 sulfate and meteorology data from 30 major cities nationwide were analyzed to examine the possible impact of the economic recession on observed sulfate concentration decreases. The results indicate that, on the average, a significant amount of the sulfate concentration drops observed in these urban areas during 2008 and 2009 cannot be explained by regulatory emission control effort alone. This is reflected in the meteorology adjusted sulfate trend. The remaining sulfate concentration decline is likely to come from additional SO2 reductions resulting from reduced economic activities, industrial productions and utility demands which was commonly realized almost everywhere in the country. Thus, it is determined that the economic recession must have a significant impact on the observed decreases of sulfate concentration in 2008 and 2009.

Chu, S.

2011-12-01

35

An analysis of trends in baseflow recession and low-flows in rain-dominated coastal streams of the pacific coast  

NASA Astrophysics Data System (ADS)

The work presented here centers on the identification and calculation of indices representative of annual low-flow conditions and baseflow recession form, and the evaluation of trends in these indices with time for rain-dominated streams of the Pacific coastal mountain ranges. Two different baseflow recession analysis techniques are employed, which when combined are capable of modeling the varied dry-season flow conditions that exist over the broad range of catchments included in the study area. Results indicate that over the past 40-80 years widespread trends of increasing rates of baseflow recession and decreasing annual low-flow conditions exist throughout the region. Of streamgages analyzed, 44% were identified as having a statistically significant trend in either low-flow conditions or recession form with time. While spring flow conditions show little change over the study period, trends of decreasing late-summer flow conditions and increasing rates of recession are particularly common. Northern California and Oregon are especially impacted locations, with upwards of 60% of study gages exhibiting decreasing trends in late summer flow conditions. Detailed conceptual explanations for the connections between trends in recession form and indices of low-flow are also presented.

Sawaske, Spencer R.; Freyberg, David L.

2014-11-01

36

Using Bzier Curve to Improve the Accuracy in Integrated Circuit Design Analysis  

E-print Network

provide smoother curves than piecewise linear functions. Among polynomial nonlinear curves, B-splines to the knots using CAD tools is sometime necessary to obtain an ideal spline curve. B-spline curves have bUsing Bézier Curve to Improve the Accuracy in Integrated Circuit Design Analysis Eric Y. Chen

Tomkins, Andrew

37

Regional estimation of catchment-scale soil properties by means of streamflow recession analysis for use in distributed hydrological models  

NASA Astrophysics Data System (ADS)

The estimation of catchment-scale soil properties, such as water storage capacity and hydraulic conductivity, is of primary interest for the implementation of distributed hydrological models at the regional scale. This estimation is generally done on the basis of information provided by soil databases. However, such databases are often established for agronomic uses and generally do not document deep weathered rock horizons (i.e. pedologic horizons of type C and deeper), which can play a major role in water transfer and storages. Here we define the Drainable Storage Capacity Index (DSCI), an indicator that relies on the comparison of cumulated streamflow and precipitation to assess catchment-scale storage capacities. The DSCI is found to be reliable to detect underestimation of soil storage capacities in soil databases. We also use the streamflow recession analysis methodology defined by Brutsaert and Nieber (Water Resources Research 13(3), 1977) to estimate water storage capacities and lateral saturated hydraulic conductivities of the non-documented deep horizons. The analysis is applied to a sample of twenty-three catchments (0.2 km² - 291 km²) located in the Cévennes-Vivarais region (south of France). In a regionalisation purpose, the obtained results are compared to the dominant catchments geology. This highlights a clear hierarchy between the different geologies present in the area. Hard crystalline rocks are found to be associated to the thickest and less conductive deep soil horizons. Schist rocks present intermediate values of thickness and of saturated hydraulic conductivity, whereas sedimentary rocks and alluvium are found to be the less thick and the most conductive. Consequently, deep soil layers with thicknesses and hydraulic conductivities differing with the geology were added to a distributed hydrological model implemented over the Cévennes-Vivarais region. Preliminary simulations show a major improvement in terms of simulated discharge when compared to simulations done without deep soil layers. KEY WORDS: hydraulic soil properties, streamflow recession, deep soil horizons, soil databases, Boussinesq equation, storage capacity, regionalisation

Vannier, Olivier; Braud, Isabelle; Anquetin, Sandrine

2013-04-01

38

Stress analysis in curved composites due to thermal loading  

NASA Astrophysics Data System (ADS)

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.

Polk, Jared Cornelius

39

Clinical characterization, genetic mapping and whole-genome sequence analysis of a novel autosomal recessive intellectual disability syndrome.  

PubMed

We identified six patients presenting with a strikingly similar clinical phenotype of profound syndromic intellectual disability of unknown etiology. All patients lived in the same village. Extensive genealogical work revealed that the healthy parents of the patients were all distantly related to a common ancestor from the 17th century, suggesting autosomal recessive inheritance. In addition to intellectual disability, the clinical features included hypotonia, strabismus, difficulty to fix the eyes to an object, planovalgus in the feet, mild contractures in elbow joints, interphalangeal joint hypermobility and coarse facial features that develop gradually during childhood. The clinical phenotype did not fit any known syndrome. Genome-wide SNP genotyping of the patients and genetic mapping revealed the longest shared homozygosity at 3p22.1-3p21.1 encompassing 11.5 Mb, with no other credible candidate loci emerging. Single point parametric linkage analysis showed logarithm of the odds score of 11 for the homozygous region, thus identifying a novel intellectual disability predisposition locus. Whole-genome sequencing of one affected individual pinpointed three genes with potentially protein damaging homozygous sequence changes within the predisposition locus: transketolase (TKT), prolyl 4-hydroxylase transmembrane (P4HTM), and ubiquitin specific peptidase 4 (USP4). The changes were found in heterozygous form with 0.3-0.7% allele frequencies in 402 whole-genome sequenced controls from the north-east of Finland. No homozygotes were found in this nor additional control data sets. Our study facilitates clinical and molecular diagnosis of patients with this novel autosomal recessive intellectual disability syndrome. However, further studies are needed to unambiguously identify the underlying genetic defect. PMID:25078763

Kaasinen, Eevi; Rahikkala, Elisa; Koivunen, Peppi; Miettinen, Sirpa; Wamelink, Mirjam M C; Aavikko, Mervi; Palin, Kimmo; Myllyharju, Johanna; Moilanen, Jukka S; Pajunen, Leila; Karhu, Auli; Aaltonen, Lauri A

2014-10-01

40

An Analysis of the Shapes of Interstellar Extinction Curves. V. The IR-Through-UV Curve Morphology  

E-print Network

We study the IR-through-UV interstellar extinction curves towards 328 Galactic B and late-O stars. We use a new technique which employs stellar atmosphere models in lieu of unreddened "standard" stars. This technique is capable of virtually eliminating spectral mismatch errors in the curves. It also allows a quantitative assessment of the errors and enables a rigorous testing of the significance of relationships between various curve parameters, regardless of whether their uncertainties are correlated. Analysis of the curves gives the following results: (1) In accord with our previous findings, the central position of the 2175 A extinction bump is mildly variable, its width is highly variable, and the two variations are unrelated. (2) Strong correlations are found among some extinction properties within the UV region, and within the IR region. (3) With the exception of a few curves with extreme (i.e., large) values of R(V), the UV and IR portions of Galactic extinction curves are not correlated with each other. (4) The large sightline-to-sightline variation seen in our sample implies that any average Galactic extinction curve will always reflect the biases of its parent sample. (5) The use of an average curve to deredden a spectral energy distribution (SED) will result in significant errors, and a realistic error budget for the dereddened SED must include the observed variance of Galactic curves. While the observed large sightline-to-sightline variations, and the lack of correlation among the various features of the curves, make it difficult to meaningfully characterize average extinction properties, they demonstrate that extinction curves respond sensitively to local conditions. Thus, each curve contains potentially unique information about the grains along its sightline.

E. L. Fitzpatrick; D. Massa

2007-05-01

41

Dissection of the hormetic curve: analysis of components and mechanisms.  

PubMed

The relationship between the dose of an effector and the biological response frequently is not described by a linear function and, moreover, in some cases the dose-response relationship may change from positive/adverse to adverse/positive with increasing dose. This complicated relationship is called "hormesis". This paper provides a short analysis of the concept along with a description of used approaches to characterize hormetic relationships. The whole hormetic curve can be divided into three zones: I - a lag-zone where no changes are observed with increasing dose; II - a zone where beneficial/adverse effects are observed, and III - a zone where the effects are opposite to those seen in zone II. Some approaches are proposed to analyze the molecular components involved in the development of the hormetic character of dose-response relationships with the use of specific genetic lines or inhibitors of regulatory pathways. The discussion is then extended to suggest a new parameter (half-width of the hormetic curve at zone II) for quantitative characterization of the hormetic curve. The problems limiting progress in the development of the hormesis concept such as low reproducibility and predictability may be solved, at least partly, by deciphering the molecular mechanisms underlying the hormetic dose-effect relationship. PMID:25249836

Lushchak, Volodymyr I

2014-07-01

42

A new approach to the analysis of Mira light curves  

NASA Technical Reports Server (NTRS)

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.

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

1990-01-01

43

Straight thinking about groundwater recession  

NASA Astrophysics Data System (ADS)

in catchment and hillslope hydrology a more nuanced approach is now taken to streamflow recession analysis, in the context of major aquifers it is commonly still assumed that the groundwater head recession rate will take exponential form, an idea originally proposed in the 19th Century. However it is shown here that, in early times, the groundwater head recession in a major aquifer should take an almost straight line form with a rate approximately equal to the long-term recharge rate divided by the aquifer storage coefficient. The length of this phase can be estimated from an analytical expression derived in the paper which depends on the aquifer diffusivity, length scale, and the position of the monitoring point. A transitional phase then leads to an exponential phase after some critical time which is independent of the position of the monitoring point. Major aquifers in a state of periodic quasi-steady state are expected to have rates of groundwater flux recession which deviate little from the average rate of groundwater recharge. Where quasi-exponential groundwater declines are observed in nature, their form may be diagnostic of particular types of aquifer properties and/or boundary effects, such as proximity to drainage boundaries, variations in transmissivity with hydraulic head, storage changes due to pumping, nonequilibrium flow at a range of spatial and temporal scales, and variations in specific yield with depth. Recession analysis has applicability to a range of groundwater problems and is powerful way of gaining insight into the hydrologic functioning of an aquifer.

Cuthbert, M. O.

2014-03-01

44

Evaluating Random Forests for Survival Analysis using Prediction Error Curves  

PubMed Central

Prediction error curves are increasingly used to assess and compare predictions in survival analysis. This article surveys the R package pec which provides a set of functions for efficient computation of prediction error curves. The software implements inverse probability of censoring weights to deal with right censored data and several variants of cross-validation to deal with the apparent error problem. In principle, all kinds of prediction models can be assessed, and the package readily supports most traditional regression modeling strategies, like Cox regression or additive hazard regression, as well as state of the art machine learning methods such as random forests, a nonparametric method which provides promising alternatives to traditional strategies in low and high-dimensional settings. We show how the functionality of pec can be extended to yet unsupported prediction models. As an example, we implement support for random forest prediction models based on the R-packages randomSurvivalForest and party. Using data of the Copenhagen Stroke Study we use pec to compare random forests to a Cox regression model derived from stepwise variable selection. Reproducible results on the user level are given for publicly available data from the German breast cancer study group.

Mogensen, Ulla B; Ishwaran, Hemant; Gerds, Thomas A

2014-01-01

45

Suspension characteristics analysis running on curve for maglev train  

Microsoft Academic Search

The suspension characteristics of maglev train are studied in this paper when it is running on different curves. The suspension gap variation when maglev train is running on three different curves are presented. And the limitation to the vertical semi-diameter of the curve at the point where the grade of the longitudinal section of the track changes is also calculated.

Xiaolong Li; Zhizhou Zhang; Zhiqiang Long

2008-01-01

46

An Analysis of the Shapes of Interstellar Extinction Curves. V. The IR-Through-UV Curve Morphology  

E-print Network

We study the IR-through-UV interstellar extinction curves towards 328 Galactic B and late-O stars. We use a new technique which employs stellar atmosphere models in lieu of unreddened "standard" stars. This technique is capable of virtually eliminating spectral mismatch errors in the curves. It also allows a quantitative assessment of the errors and enables a rigorous testing of the significance of relationships between various curve parameters, regardless of whether their uncertainties are correlated. Analysis of the curves gives the following results: (1) In accord with our previous findings, the central position of the 2175 A extinction bump is mildly variable, its width is highly variable, and the two variations are unrelated. (2) Strong correlations are found among some extinction properties within the UV region, and within the IR region. (3) With the exception of a few curves with extreme (i.e., large) values of R(V), the UV and IR portions of Galactic extinction curves are not correlated with each othe...

Fitzpatrick, E L

2007-01-01

47

GRB Swift X-ray light curves analysis (Margutti+, 2013)  

NASA Astrophysics Data System (ADS)

We present a comprehensive statistical analysis of Swift X-ray light curves of gamma-ray bursts (GRBs) collecting data from more than 650 GRBs discovered by Swift and other facilities. The unprecedented sample size allows us to constrain the rest-frame X-ray properties of GRBs from a statistical perspective, with particular reference to intrinsic time-scales and the energetics of the different light-curve phases in a common rest-frame 0.3-30keV energy band. Temporal variability episodes are also studied and their properties constrained. Two fundamental questions drive this effort: (i) Does the X-ray emission retain any kind of 'memory' of the prompt ?-ray phase? (ii) Where is the dividing line between long and short GRB X-ray properties? We show that short GRBs decay faster, are less luminous and less energetic than long GRBs in the X-rays, but are interestingly characterized by similar intrinsic absorption. We furthermore reveal the existence of a number of statistically significant relations that link the X-ray to prompt ?-ray parameters in long GRBs; short GRBs are outliers of the majority of these two-parameter relations. However and more importantly, we report on the existence of a universal three-parameter scaling that links the X-ray and the ?-ray energy to the prompt spectral peak energy of both long and short GRBs: EX,iso{prop.to}E1.00+/-0.06?,iso/E0.60+/-0.10pk. (3 data files).

Margutti, R.; Zaninoni, E.; Bernardini, M. G.; Chincarini, G.; Pasotti, F.; Guidorzi, C.; Angelini, L.; Burrows, D. N.; Capalbi, M.; Evans, P. A.; Gehrels, N.; Kennea, J.; Mangano, V.; Moretti, A.; Nousek, J.; Osborne, J. P.; Page, K. L.; Perri, M.; Racusin, J.; Romano, P.; Sbarufatti, B.; Stafford, S.; Stamatikos, M.

2013-11-01

48

Scoliosis associated with syringomyelia: analysis of MRI and curve progression  

PubMed Central

Little is known about the natural history of scoliosis found in patients with syringomyelia, including the factors affecting scoliosis curve progression and the effect of syrinx drainage treatment. Twenty patients having scoliosis with syringomyelia diagnosed by MRI were followed up for 6.6 (range 2.0–12.6) years on an average. Various factors potentially influencing curve pattern or progression in these patients were then retrospectively reviewed. The convex side of major curve of scoliosis tended to be on the same side as the syrinx and as the unilateral neurologic abnormality. No correlation was found between the location and the size of the syrinx and the location and size of the major curve of the scoliosis, or between the severity of neurologic deficit and the size of the major curve of the scoliosis. In patients under the age of ten at the time of diagnosis of scoliosis and with a flexible curve, decompression of the syrinx improved or stabilized scoliosis. In most patients over the age of ten, surgical treatment of the scoliosis was necessary because of the large initial size of the curve or progression of the curve even after syrinx drainage. Other factors including gender, location of the syrinx, type of the curve, and severity of neurologic deficits did not correlate with the progression of the curve. The results of this retrospective study suggest that early diagnosis and decompression of a syrinx in scoliosis patients especially under the age of ten is crucial and may decrease the curve size and limit scoliosis curve progression. PMID:17701226

Yeom, Jin Sup; Lee, Choon-Ki; Park, Kun-Woo; Lee, Jae Hyup; Lee, Dong-Ho; Wang, Kyu-Chang

2007-01-01

49

Hybrid analytical technique for the nonlinear analysis of curved beams  

NASA Technical Reports Server (NTRS)

The application of a two-step hybrid technique to the geometrically nonlinear analysis of curved beams is used to demonstrate the potential of hybrid analytical techniques in nonlinear structural mechanics. The hybrid technique is based on successive use of the perturbation method and a classical direct variational procedure. The functions associated with the various-order terms in the perturbation expansion of the fundamental unknowns, and their sensitivity derivatives with respect to material and geometric parameters of the beam, are first obtained by using the perturbation method. These functions are selected as coordinate functions (or modes) and the classical direct variational technique is then used to compute their amplitudes. The potential of the proposed hybrid technique for nonlinear analysis of structures is discussed. The effectiveness of the hybrid technique is demonstrated by means of numerical examples. The symbolic computation system Mathematica is used in the present study. The tasks performed on Mathematica include: (1) generation of algebraic expressions for the perturbation functions of the different response quantities and their sensitivity derivatives: and (2) determination of the radius of convergence of the perturbation series.

Noor, A. K.; Andersen, C. M.

1992-01-01

50

Genetic analysis and molecular mapping of a novel recessive gene xa34(t) for resistance against Xanthomonas oryzae pv. oryzae.  

PubMed

A new bacterial blight recessive resistance gene xa34(t) was identified from the descendant of somatic hybridization between an aus rice cultivar (cv.) BG1222 and susceptible cv. IR24 against Chinese race V (isolate 5226). The isolate was used to test the resistance or susceptibility of F(1) progenies and reciprocal crosses of the parents. The results showed that F(1) progenies appeared susceptibility there were 128R (resistant):378S (susceptible) and 119R:375S plants in F(2) populations derived from two crosses of BG1222/IR24 and IR24/BG1222, respectively, which both calculates into a 1R:3S ratio. 320 pairs of stochastically selected SSR primers were used for genes' initial mapping. The screened results showed that two SSR markers, RM493 and RM446, found on rice chromosome 1 linked to xa34(t). Linkage analysis showed that these two markers were on both sides of xa34(t) with the genetic distances 4.29 and 3.05 cM, respectively. The other 50 SSR markers in this region were used for genes' fine mapping. The further results indicated that xa34(t) was mapped to a 1.42 cM genetic region between RM10927 and RM10591. In order to further narrow down the genomic region of xa34(t), 43 of insertion/deletion (Indel) markers (BGID1-43) were designed according to the sequences comparison between japonica and indica rice. Parents' polymorphic detection and linkage assay showed that the Indel marker BGID25 came closer to the target gene with a 0.4 cM genetic distance. A contig map corresponding to the locus was constructed based on the reference sequences aligned by the xa34(t) linked markers. Consequently, the locus of xa34(t) was defined to a 204 kb interval flanked by markers RM10929 and BGID25. PMID:21274511

Chen, Shen; Liu, Xinqiong; Zeng, Liexian; Ouyang, Dongmei; Yang, Jianyuan; Zhu, Xiaoyuan

2011-05-01

51

Estimating basin-wide hydraulic parameters of a semi-arid mountainous watershed by recession-flow analysis  

E-print Network

hydraulic parameters, hydraulic conductivity or transmissivity is the most problematic to obtain, in part. Usually, hydraulic conductivity is unsatis- factorily estimated based on laboratory measurements, whichEstimating basin-wide hydraulic parameters of a semi-arid mountainous watershed by recession

Walter, M.Todd

52

Analysis of missense variants in the PKHD1 -gene in patients with autosomal recessive polycystic kidney disease (ARPKD)  

Microsoft Academic Search

Autosomal recessive polycystic kidney disease (ARPKD) is a severe form of polycystic kidney disease characterized by enlarged kidneys and congenital hepatic fibrosis. Given the poor prognosis for the majority of children with the severe perinatal ARPKD phenotype, there is a regular request for prenatal testing. ARPKD is caused by mutations in the polycystic kidney and hepatic disease 1 (PKHD1) gene,

Monique Losekoot; Cathleen Haarloo; Claudia Ruivenkamp; Stefan J. White; Martijn H. Breuning; Dorien J. M. Peters

2005-01-01

53

Light curves of type II supernovae. 2: The analysis  

Microsoft Academic Search

All photometric observations of Type II Supernovae published to date, and collected in Paper 1, have been reanalyzed along with data from SN spectroscopy. The light curves are very different both as saturation and slopes of the different portions. For sake of simplicity, the average decline rates have been used to describe the gross characteristics of the light curves. It

F. Patat; R. Barbon; E. Cappellaro; M. Turatto

1994-01-01

54

Multidimensional Analysis of Learning Curves in Laparoscopic Sigmoid Resection  

Microsoft Academic Search

PURPOSE: The number of operations to reach a plateau phase in colorectal laparoscopic surgery is still under debate. There are few publications reporting on multidimensional assessment of the learning curve, including operation time and complication and conversion rates. The purpose of this study was to define a multidimensional learning curve for sigmoid resection performed by two surgeons with experience in

Selim Dinçler; Michael T. Koller; Johann Steurer; Lucas M. Bachmann; Daniel Christen; Peter Buchmann

2003-01-01

55

On the base flow recession at the Panola Mountain Research Watershed, Georgia, United States  

NASA Astrophysics Data System (ADS)

There are two types of nonlinearity for recession slope curves: (1) the data cloud of observed ln(-dQ/dt) versus ln(Q) along a straight line where the slope is not equal to 1, and (2) the data cloud of observed ln(-dQ/dt) versus ln(Q) is concave or convex. From the 0.1 ha hillslope, the 10 ha headwater subwatershed, and the 41 ha watershed at the Panola Mountain Research Watershed (PMRW), the observed ln(-dQ/dt) versus ln(Q) changes from convex to concave. This has been explained by the spatial heterogeneity of recession properties and nonlinearity of hillslope hydraulics. Hillslope bedrock leakage and return flow to the perennial riparian zone aquifer are important factors affecting the ln(-dQ/dt) versus ln(Q) relations, and an assessment of this mechanism for explaining the observed base flow recessions at the PMRW is the sole focus of this research. As a result, the lower envelope and the upper envelope should be used to estimate the recession parameters for the 0.1 ha hillslope and the 41 ha watershed, respectively, and the recession at the 10 ha watershed is a mixture of them. Based on the recession analysis, the leakage to the bedrock on the hillslope and return flow to the perennial stream riparian groundwater can be estimated, and the estimation can be verified by other studies.

Wang, Dingbao

2011-03-01

56

On the Design and Analysis of Modified Koch Curve Fractal Antenna  

NASA Astrophysics Data System (ADS)

A comparative study of the conventional and modified Koch curve antennas has been analyzed. The geometries of the antennas are obtained by an iterative function system algorithm for fractal curve generation. It has been observed that by keeping height and width of curve constant the modified Koch curve antenna provide more resonant frequencies with better return loss in comparison with conventional Koch curve antenna. The presented analysis quantifies the advantages provided by the modified Koch curve antenna and is validated by simulations and experimental results.

Rani, S.; Singh, A. P.

2013-12-01

57

Recessive Forms of OI  

MedlinePLUS

... and odds of recurrence • Expands information available to genetic counselors regarding severely affected infants • Allows siblings of a person diagnosed with recessive OI to obtain testing to determine their carrier status • Allows for prenatal diagnosis in an affected family Testing for Recessive ...

58

Uniformly valid asymptotic flow analysis in curved channels  

NASA Astrophysics Data System (ADS)

The laminar incompressible flow in a two-dimensional curved channel having at its upstream and downstream extremities two tangent straight channels is considered. A global interactive boundary layer (GIBL) model is developed using the approach of the successive complementary expansions method (SCEM) which is based on generalized asymptotic expansions leading to a uniformly valid approximation. The GIBL model is valid when the non dimensional number ? =?Re1/3 is O(1) and gives predictions in agreement with numerical Navier-Stokes solutions for Reynolds numbers Re ranging from 1 to 104 and for constant curvatures ? =H/Rc ranging from 0.1 to 1, where H is the channel width and Rc the curvature radius. The asymptotic analysis shows that ?, which is the ratio between the curvature and the thickness of the boundary layer of any perturbation to the Poiseuille flow, is a key parameter upon which depends the accuracy of the GIBL model. The upstream influence length is found asymptotically and numerically to be O(Re1/7).

Zagzoule, M.; Cathalifaud, P.; Cousteix, J.; Mauss, J.

2012-01-01

59

Three-Dimensional Postbuckling Analysis of Curved Beams  

NASA Technical Reports Server (NTRS)

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.

Pai, P. Frank; Lee, Seung-Yoon

2002-01-01

60

Analysis of curved target-type thrust reversers  

Microsoft Academic Search

The jet deflection properties of inviscid, incompressible curved surfaces are investigated through the use of numerical methods. Leve-Civita's method is applied to plane jets impinging symmetrically on two-dimensional curved surfaces whose shapes are specified in terms of a given jet-deflection angle and the angle of departure at the lip of the two-dimensional bucket. This method enables one to round off

Turgut Sarpkaya; G. Hiriart

1975-01-01

61

Autosomal recessive juvenile parkinsonism  

Microsoft Academic Search

Autosomal recessive juvenile parkinsonism (AR-JP) is a hereditary neurodegenerative disorder characterized by levodopa-responsive parkinsonism with onset before age 40 years and a slowly progressive course. Families with this condition have been described predominantly in Japanese population, occasionally under different names including an autosomal recessive early-onset parkinsonism with diurnal fluctuation (AR-EPDF) or a familial form of juvenile parkinsonism. Recently, the causative

Masaaki Saito; Mieko Maruyama; Ken Ikeuchi; Hiroshi Kondo; Atsushi Ishikawa; Tatsuhiko Yuasa; Shoji Tsuji

2000-01-01

62

Spectral curve fitting for automatic hyperspectral data analysis  

Microsoft Academic Search

Automatic discovery and curve fitting of absorption bands in hyperspectral data can enable the analyst to identify materials present in a scene by comparison with library spectra. This procedure is common in laboratory spectra, but is challenging for sparse hyperspectral data. A procedure for robust discovery of overlapping bands in hyperspectral data is described in this paper. The method is

Adrian Jon Brown

2006-01-01

63

Transit Light Curves with Finite Integration Time: Fisher Information Analysis  

E-print Network

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 (TESS) 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 tran...

Price, Ellen M

2014-01-01

64

Transit Light Curves with Finite Integration Time: Fisher Information Analysis  

NASA Astrophysics Data System (ADS)

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.

Price, Ellen M.; Rogers, Leslie A.

2014-10-01

65

Thermal sensitivity analysis of curved bi-material microcantilevers  

NASA Astrophysics Data System (ADS)

Thermal sensitivity of bi-material microcantilevers plays a crucial role in temperature sensors and thermal actuators. Thermal loading experiments on bi-material microcantilevers show the dependence of thermal sensitivity on microcantilever curvature and width which is not addressed by currently used analytical models. In this work, a new thermal sensitivity model for curved bi-material microcantilevers is presented which correlates such dependence to the increase of microcantilever flexural rigidity caused by transverse curvature. The new model is validated against the results of thermal loading experiments carried out on gold-polysilicon and SU-8/silicon nitride bi-material microcantilevers with different widths and initial curvatures.

Najafi Sohi, Ali; Nieva, Patricia M.

2014-11-01

66

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

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

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

2012-01-01

67

Latent growth curve modeling as an integrative approach to the analysis of change  

Microsoft Academic Search

Latent Growth Curve Models (LGCM) are discussed as a general data-analytic approach to the analysis of change. Conventional, but popular, methods of analyzing change over time, such as the paired t-test, repeated measures ANOVA, or MANOVA, have a tradition, which is quite different from the more recently developed latent growth curve models. While the former originated from the idea of

MANUEL C. VOELKLE

2007-01-01

68

New method for calculating a mathematical expression for streamflow recession  

USGS Publications Warehouse

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.

Rutledge, Albert, T.

1991-01-01

69

Spectral Curve Fitting for Automatic Hyperspectral Data Analysis  

E-print Network

Automatic discovery and curve fitting of absorption bands in hyperspectral data can enable the analyst to identify materials present in a scene by comparison with library spectra. This procedure is common in laboratory spectra, but is challenging for sparse hyperspectral data. A procedure for robust discovery of overlapping bands in hyperspectral data is described in this paper. The method is capable of automatically discovering and fitting symmetric absorption bands, can separate overlapping absorption bands in a stable manner, and has relatively low sensitivity to noise. A comparison with techniques already available in the literature is presented using simulated spectra. An application is demonstrated utilizing the shortwave infrared (2.0-2.5 micron or 5000-4000 cm-1) region. A small hyperspectral scene is processed to demonstrate the ability of the method to detect small shifts in absorption wavelength caused by varying white mica chemistry in a natural setting.

Brown, Adrian J

2014-01-01

70

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

PubMed Central

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

Zhang, Ren; Zhang, Chun-Ting

2014-01-01

71

Determination of the optimum working range from a calibration curve for colorimetric analysis with an "autoanalyzer".  

PubMed

A study has been made of the types and distribution of errors in determining the optimum working range from a calibration curve for automated analysis. Three error equations are derived for the fitting of a linear, quadratic or cubic curve, involving a thorough statistical analysis of the data. The errors from a set of silica and alumina standards, requiring a quadratic and cubic fit respectively, compare favourably with replicate analyses of standard rocks done on a previous occasion. PMID:18961254

Whitehead, D

1973-02-01

72

Estimation of isodose curves in radiation therapy and related response analysis  

E-print Network

ESTIMATION OF ISODOSE CURVES IN RADIATION THERAPY AND RELATED RESPONSE ANALYSIS A Thesis By JAMES CAMPBELL GOODLETT Submitted to the Graduate College oi' the Texas A@M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE May 1967 Major Subject: Statistic s ESTIMATION OF ISODOSE CURVES IN RADIATION THERAPY AND RELATED RESPONSE ANALYSIS A Thesis By JAMES CAMPBELL GOODLETT Approved as and content by: ( airm n of Committee) Ot~+ (Head...

Goodlett, James Campbell

2012-06-07

73

Analysis of well test data influenced by multiple reservoir boundaries using pressure derivative type curves  

E-print Network

ANALYSIS OF WELL TEST DATA INFLUENCED BY MULTIPLE RESERVOIR BOUNDARIES USING PRESSURE DERIVATIVE TYPE CURVES A Thesis CHARLES BRETT. BUZARDE Submitted to the Office of Graduate Studies of Texas AIIiM University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 1991 Major Subject: Petroleum Engineering ANALYSIS OF WELL TEST DATA INFLUENCED BY MULTIPLE RESERVOIR BOUNDARIES USING PRESSURE DERIVATIVE TYPE CURVES A Thesis by CHARLES BRETT BUZARDE Approved...

Buzarde, Charles Brett

2012-06-07

74

Identification of feline polycystic kidney disease mutation using fret probes and melting curve analysis  

Microsoft Academic Search

We developed and validated a real-time polymerase chain reaction (PCR) assay using fluorescent hybridization probes and melting curve analysis to identify the PKD1 exon 29 (C?A) mutation, which is implicated in polycystic kidney disease of cats. DNA was isolated from peripheral blood of 20 Persian cats. The employ of the new real-time PCR and melting curve analysis in these samples

A. Criado-Fornelio; A. Buling; J. C. Barba-Carretero

2009-01-01

75

Parent involvement and science achievement: A latent growth curve analysis  

NASA Astrophysics Data System (ADS)

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.

Johnson, Ursula Yvette

76

Quantitation of DNA methylation by melt curve analysis  

PubMed Central

Background Methylation of DNA is a common mechanism for silencing genes, and aberrant methylation is increasingly being implicated in many diseases such as cancer. There is a need for robust, inexpensive methods to quantitate methylation across a region containing a number of CpGs. We describe and validate a rapid, in-tube method to quantitate DNA methylation using the melt data obtained following amplification of bisulfite modified DNA in a real-time thermocycler. Methods We first describe a mathematical method to normalise the raw fluorescence data generated by heating the amplified bisulfite modified DNA. From this normalised data the temperatures at which melting begins and finishes can be calculated, which reflect the less and more methylated template molecules present respectively. Also the T50, the temperature at which half the amplicons are melted, which represents the summative methylation of all the CpGs in the template mixture, can be calculated. These parameters describe the methylation characteristics of the region amplified in the original sample. Results For validation we used synthesized oligonucleotides and DNA from fresh cells and formalin fixed paraffin embedded tissue, each with known methylation. Using our quantitation we could distinguish between unmethylated, partially methylated and fully methylated oligonucleotides mixed in varying ratios. There was a linear relationship between T50 and the dilution of methylated into unmethylated DNA. We could quantitate the change in methylation over time in cell lines treated with the demethylating drug 5-aza-2'-deoxycytidine, and the differences in methylation associated with complete, clonal or no loss of MGMT expression in formalin fixed paraffin embedded tissues. Conclusion We have validated a rapid, simple in-tube method to quantify methylation which is robust and reproducible, utilizes easily designed primers and does not need proprietary algorithms or software. The technique does not depend on any operator manipulation or interpretation of the melt curves, and is suitable for use in any laboratory with a real-time thermocycler. The parameters derived provide an objective description and quantitation of the methylation in a specimen, and can be used to for statistical comparisons of methylation between specimens. PMID:19393074

2009-01-01

77

Are we thinking straight about groundwater recession?  

NASA Astrophysics Data System (ADS)

By exploring what governs the form of groundwater head recession in idealised and real aquifers, it will be shown that the analysis of groundwater recessions is a powerful but underused way of gaining insight into the hydrologic functioning of an aquifer from local to regional scales. It is commonly assumed that groundwater head recession in aquifers will take exponential form. However, here it is demonstrated that ideal regional aquifers should, given enough time between recharge events, actually develop through three distinct phases of recession: (1) in early times the groundwater recession should take an almost straight line form with a rate approximately equal to the long term recharge rate divided by the specific yield. The length of this phase can be estimated from a new analytical expression, which depends on the aquifer diffusivity, length scale and the position of the monitoring point, (2) a transitional phase then leads to, (3) an exponential phase after some critical time which is described by an existing analytical expression which is independent of the position of the monitoring point. Further analysis reveals that major aquifers in a state of periodic quasi-steady state are expected to have rates of net groundwater drainage which deviate little from the average rate of groundwater recharge. To back up these theoretical considerations, a range of real groundwater hydrographs will be presented which demonstrate the characteristic behaviour and interactions of groundwater flow systems interacting at local to regional scales. Where groundwater declines are observed in nature to have a quasi-exponential form, this may be diagnostic of particular types of aquifer properties and/or boundary effects such as: storage changes due to pumping, proximity to drainage boundaries, variations in transmissivity with hydraulic head, and variations in specific yield with depth. Furthermore, 'non-equilibrium' flow at a range of spatial and temporal scales helps explain the recession behaviour of nested flow systems where local scale and regional scale recessions become superposed.

Cuthbert, M. O.

2013-12-01

78

Analysis, design and construction of curved composite girder bridges: State-of-the-art  

Microsoft Academic Search

The horizontally curved composite girder bridges have excellent properties, such as quick construction, good seismic performance,\\u000a saving construction formwork and convenience in spatial arrangement.etc, which have greatly promoted the application of such\\u000a bridges. The objective of this paper is to provide and summarize important references related to the analysis, design and\\u000a construction of curved composite girder bridges. Subjects discussed in

Weiwei Lin; Teruhiko Yoda

2010-01-01

79

Rapid genotyping of beak and feather disease virus using high-resolution DNA melt curve analysis.  

PubMed

Beak and feather disease virus (BFDV) is a significant pathogen both for wild and captive psittacine birds globally. Genotypic differentiation of BFDV isolates is crucial to establish effective control strategies for the conservation of endangered species and epidemiological investigations of disease outbreaks. The technique developed in this study is a simple, rapid and inexpensive genotyping method for BFDV using PCR and subsequent high-resolution melt (HRM) curve analysis. This was achieved using PCR amplification of the conserved Rep gene in the presence of a fluorescent DNA intercalating dye (SYTO9). HRM curve analysis of the resultant amplicon could readily differentiate between reference strain (92-SR14) and 18 other BFDV isolates used in this study. Analysis of the nucleotide sequences of the amplicon from each isolate revealed that each melt curve profile was related to a unique DNA sequence. The potential of the PCR-HRM curve analysis to differentiate inter-host genetic variation among critically endangered orange-bellied parrots, lorikeets and cockatoos was also evaluated. Phylogenetic tree topology based on partial Rep gene sequences used in this study showed that BFDV Rep gene sequence patterns were correlated with the results of HRM curve analysis. The results presented in this study indicate that this technique could be used in both clinical research and differentiation of BFDV isolates in a fraction of time without further nucleotide sequencing and provides a novel approach for the genetic screening of BFDV in clinical virology laboratories. PMID:25102431

Sarker, Subir; Ghorashi, Seyed A; Forwood, Jade K; Raidal, Shane R

2014-11-01

80

Application of the normalization data analysis technique for single specimen R-curve determination  

SciTech Connect

The authors conclude that the normalization technique for single specimen R-curve and J{sub IC} determination can be very effective. Much like EPD, this technique requires some user interpretation/judgement during data analysis and may be difficult to standardize or fully automate even with strict analysis rules.

Porr, W.C.; Mills, W.J.

1999-03-01

81

Diagnostic analysis based on ROC curves: theory and applications in medicine  

Microsoft Academic Search

Receiver operating characteristic (ROC) analysis is a powerful tool to measure and specify the problems with diagnostic performance in medicine. Describes this analysis and the importance of the index area under ROC curve, using some examples to demonstrate its application. The study was conducted on two sets of new-borns with very low birth weight, coming from neonatal intensive care units

Ana Cristina Braga; Pedro Oliveira

2003-01-01

82

A new methodology for free wake analysis using curved vortex elements  

NASA Technical Reports Server (NTRS)

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.

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

1987-01-01

83

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

NASA Astrophysics Data System (ADS)

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.

Debski, Bart?omiej; Zo?a, Stanis?aw

2014-09-01

84

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

NASA Astrophysics Data System (ADS)

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.

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

2011-08-01

85

Fractal analysis of light curves for the microquasar GX 339-4  

NASA Astrophysics Data System (ADS)

Results of a fractal analysis of the X-ray light curves from accreting black holes in low-mass binary systems are presented for the object GX 339-4 as an example. The fractal dimension of the light curves is shown to be strongly dependent on the presence of quasi-periodic oscillations (QPOs) in the observations. A correlation between the fractal dimension of the light curves and the frequency of the QPO peak has been revealed. A method supplementary to a Fourier analysis that allows the pattern of accretion disk emission as a function of time scales to be investigated is proposed. The results of this analysis can be explained if the accretion disk is separated by the QPO region into two zones with different emission parameters.

Prosvetov, A. V.; Grebenev, S. A.

2014-11-01

86

Who Suffers during Recessions? NBER Working Paper No. 17951  

ERIC Educational Resources Information Center

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…

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

2012-01-01

87

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

ERIC Educational Resources Information Center

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…

Beecher, Constance C.

2011-01-01

88

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

ERIC Educational Resources Information Center

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…

Hwu, Fenfang; Pan, Wei; Sun, Shuyan

2014-01-01

89

Frechet means of curves for signal averaging and application to ECG data analysis  

E-print Network

Fr´echet means of curves for signal averaging and application to ECG data analysis J´er´emie Bigot a reference template. We apply this approach to the estimation of a mean heart cycle from ECG records; Deformable models; ECG data. AMS classifications: Primary 62G08; secondary 62P10. Acknowledgements

Paris-Sud XI, Université de

90

Global Analysis of KOI-977: Spectroscopy, Asteroseismology, and Phase-curve Analysis  

E-print Network

We present a global analysis of KOI-977, one of the planet host candidates detected by {\\it Kepler}. 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 in the red clump, but its estimated radius ($\\gtrsim 20R_\\odot=0.093$ AU) is much larger than KOI-977.01's orbital distance ($\\sim 0.027$ AU) estimated from its period ($P_\\mathrm{orb}\\sim 1.35$ 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 ...

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

2014-01-01

91

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

PubMed Central

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).

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

92

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

PubMed

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

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

93

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

PubMed Central

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

2013-01-01

94

Thermal deformation analysis of curved actuator LIPCA with a piezoelectric ceramic layer and fiber composite layers  

Microsoft Academic Search

This paper reports thermal deformation analysis of LIPCA-C2 (Lightweight Piezo-composite Curved Actuator) that is lighter than other conventional piezo-composite type actuator. The LIPCA is composed of a piezoelectric ceramic layer which is sandwiched with composite layers having different CTE (coefficient of thermal expansion) and modulus. Due to the asymmetrical lay-up structure of LIPCA, an accurate analysis of thermally induced curvature

K. J. Yoon; K. H. Park; H. C. Park; D. Perreux

2003-01-01

95

Autosomal recessive polycystic kidney disease  

Microsoft Academic Search

Autosomal recessive polycystic kidney disease is a rare inherited disorder which usually becomes clinically manifest in early childhood, whereas autosomal dominant polycystic kidney disease usually is a disorder of adult onset. With increasing knowledge and improving diagnostic techniques, it becomes evident that the spectrum of both entities is much more variable than generally known. The presentation of autosomal recessive polycystic

K. Zerres

1992-01-01

96

Identification of feline polycystic kidney disease mutation using fret probes and melting curve analysis.  

PubMed

We developed and validated a real-time polymerase chain reaction (PCR) assay using fluorescent hybridization probes and melting curve analysis to identify the PKD1 exon 29 (C-->A) mutation, which is implicated in polycystic kidney disease of cats. DNA was isolated from peripheral blood of 20 Persian cats. The employ of the new real-time PCR and melting curve analysis in these samples indicated that 13 cats (65%) were wild type homozygotes and seven cats (35%) were heterozygotes. Both PCR-RFLP and sequencing procedures were in full agreement with real-time PCR test results. Sequence analysis showed that the mutant gene had the expected base change compared to the wild type gene. The new procedure is not only very reliable but also faster than the techniques currently applied for diagnosis of the mutation. PMID:18556032

Criado-Fornelio, A; Buling, A; Barba-Carretero, J C

2009-02-01

97

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

SciTech Connect

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)

Gensler, A.; Knoll, A.; Kuehnel, K. [AREVA, AREVA NP GmbH, Freyeslebenstr. 1, D-91058 Erlangen (Germany)

2007-07-01

98

Global heat transfer analysis in Czochralski silicon furnace with radiation on curved specular surfaces  

Microsoft Academic Search

Numerical analysis of global heat transfer with coupled thermal radiation and heat conduction is investigated in Czochralski\\u000a silicon crystal growth furnace with curved diffuse and specular surfaces. The finite element method and the radiation element\\u000a method are adopted to solve the global heat transfer and the radiative heat exchange, respectively. The emphasis focuses on\\u000a the discussion of the influence of

Z. Guo; S.-H. Hahn; S. Maruyama; T. Tsukada

1999-01-01

99

Application of neural networks to pulse-shape analysis of Bragg curves  

NASA Astrophysics Data System (ADS)

A novel approach is presented to extract relevant parameters associated with the energy loss of ejectiles from nuclear reactions obtained by digitizing the signals of a Bragg curve spectrometer. New and more powerful computational paradigms allow a more thorough pulse-shape analysis. This is fulfilled using a back-propagation artificial neural network as a pattern identifier. The known problem of over-training is discussed.

Vega, J. J.; Reynoso, R.

2006-01-01

100

Characterization of the mutation causative for autosomal recessive hereditary nephropathy in the english cocker spaniel and analysis of gene expression in multiple models of hereditary nephropathy  

E-print Network

syndrome (AS), a group of heterogeneous, hereditary renal diseases, is one example of such a human disease. The disease is transmitted in three fashions: X-linked, autosomal recessive, and autosomal dominant. AS is caused by mutations in COL4?3, COL4?4...

Davidson, Ashley Greene

2009-05-15

101

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

NASA Astrophysics Data System (ADS)

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.

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

2001-07-01

102

Updated UBV Light-Curve and Period Analysis of Eclipsing Binary HS Herculis  

NASA Astrophysics Data System (ADS)

UBV light-curves of the eclipsing binary HS Herculis, obtained in 2002 2003 observational seasons, were analysed with Wilson-Devinney computer code. New absolute dimensions of the system were calculated using the results of the light-curve analysis. Period variation of the system was also investigated. Several new times of minima have been secured for this problematic system. An apsidal motion with a period of 80.7 years was confirmed and a third body in a pretty eccentric orbit (e 3 = 0.90 ± 0.08) with a period of 85.4 years was found. The corresponding internal structure constants of the binary system, log k 2, and the mass of the third body were derived.

Bozkurt, Zeynep; De?irmenci, Ömer Lütfi

2006-08-01

103

Updated UBV Light-Curve and Period Analysis of Eclipsing Binary HS Herculis  

NASA Astrophysics Data System (ADS)

UBV light-curves of the eclipsing binary HS Herculis, which obtained in 2002--2003 observational seasons, were analysed with Wilson-Devinney computer code. New absolute dimensions of the system were calculated using the results of the light-curve analysis. Period variation of the system also investigated. Several new times of minima have been secured for this problematic system. An apsidal motion with the period of 80.7 years was confirmed and a third body in an pretty eccentric orbit (e 3 = 0.90 ± 0.08) with a period of 85.4 years was found. The corresponding internal structure constants of the binary system, log k 2, and mass of third body were derived.

Bozkurt, Zeynep; De?irmenci, Ömer Lütfi

2006-08-01

104

Analysis of pendulum-structure influencing on guidance systm for high-speed Maglev train running on curve  

Microsoft Academic Search

For Analysis of curve-running performances and influencing factors of maglev guidance system. This paper is based on double bogies system and investigates influences of pendulum-structure when system running on the curve. Firstly, system structure and simplification conditions are described. Secondly, dynamics model of carriage and kinematics model of bogies have been set up. Thirdly, formulas of movement and pulling forces

Chunxia Zhao; Longhua She; Wensen Chang

2011-01-01

105

Analysis of rotation curves in the framework of the gravitational suppression model.  

PubMed

We present an analysis of suitable rotation curves (RCs) of eight galaxies, aimed at checking the consistency and universality of the gravitational suppression (GraS) hypothesis, a phenomenological model for a new interaction between dark matter and baryons. Motivated by the puzzle of the core versus cusp distribution of dark matter in the center of halos, this hypothesis claims to reconcile the predictions from N-body Lambda cold dark matter simulations with kinematic observations. The GraS model improves the kinematic fitting residuals, but the mass parameters are unphysical and put the theory in difficulty. PMID:17501334

Martins, Christiane Frigerio; Salucci, Paolo

2007-04-13

106

Light curve analysis of rapidly variable astronomical objects in the MANIA experiment  

NASA Astrophysics Data System (ADS)

We present methods and algorithms of plotting, modeling and statistical analysis of light curves in the experiment MANIA, and illustrate their using in processing the results of observations of Nova Persei (GRO J0422+32) made with the 6 m telescope in 1992. The algorithms are realized in the language C (Linux) using the graphic package Libsx. Variability of Nova Per was analysed. It was found that the most characteristic duration of flashes is about 0.5s and that there exists inverse correlation between the amplitude and the duration of flashes.

Beskin, G. M.; Pavlova, V. V.; Plokhotnichenko, V. L.

107

The first light-curve analysis of eclipsing binaries observed by the INTEGRAL/OMC  

E-print Network

Three Algol-type binaries in Cygnus constellation were selected for an analysis from a huge database of observations made by the INTEGRAL/OMC camera. These data were processed and analyzed, resulting in a first light-curve study of these neglected eclipsing binaries. The temperatures of the primary components range from 9500 K to 10500 K and the inclinations are circa 73deg (for PV Cyg and V1011 Cyg), while almost 90deg for V822 Cyg. All of them seem to be main-sequence stars, well within their critical Roche lobes. Nevertheless, further detailed analyses are still needed.

P. Zasche

2008-04-24

108

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

ERIC Educational Resources Information Center

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…

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

2008-01-01

109

Computer Program for Predicting Recharge with a Master Recession Curve.  

National Technical Information Service (NTIS)

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 usi...

C. S. Heppner, J. R. Nimmo

2005-01-01

110

[Autosomal recessive forms of Charcot-Marie-Tooth disease].  

PubMed

In some countries with a high prevalence of consanguineous mariage, autosomal recessive inheritance probably accounts for the vast majority of all forms of CMT. Like dominant forms, autosomal recessive forms are generally subdivided into demyelinating forms (autosomal recessive CMT1: AR-CMT1 or CMT4) and axonal forms (AR-CMT2). Genetic analysis of large families with recessive transmission has identified several novel CMT-related genes (GDAP1, MTMR2, MTMR13, KIAA1985, NDGR1, periaxin and lamin). Given the clinical, electrophysiological and histological heterogeneity of this disease, numerous culprit genes probably remain to be discovered, leading to an even more complex classification. Clinical and histological features often point to the involvement of a particular gene. Nerve biopsy and molecular studies can contribute to the diagnosis, but this approach is highly time-consuming and can only be performed in specialized laboratories. PMID:16119880

Vallat, Jean-Michel; Grid, Djamel; Magdelaine, Corinne; Sturtz, Franck; Levy, Nicolas; Tazir, Mériem

2005-01-01

111

Antigen-antibody biorecognition events as discriminated by noise analysis of force spectroscopy curves.  

PubMed

Atomic force spectroscopy is able to extract kinetic and thermodynamic parameters of biomolecular complexes provided that the registered unbinding force curves could be reliably attributed to the rupture of the specific complex interactions. To this aim, a commonly used strategy is based on the analysis of the stretching features of polymeric linkers which are suitably introduced in the biomolecule-substrate immobilization procedure. Alternatively, we present a method to select force curves corresponding to specific biorecognition events, which relies on a careful analysis of the force fluctuations of the biomolecule-functionalized cantilever tip during its approach to the partner molecules immobilized on a substrate. In the low frequency region, a characteristic 1/f (?) noise with ? equal to one (flickering noise) is found to replace white noise in the cantilever fluctuation power spectrum when, and only when, a specific biorecognition process between the partners occurs. The method, which has been validated on a well-characterized antigen-antibody complex, represents a fast, yet reliable alternative to the use of linkers which may involve additional surface chemistry and reproducibility concerns. PMID:25073811

Bizzarri, Anna Rita; Cannistraro, Salvatore

2014-08-22

112

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

NASA Technical Reports Server (NTRS)

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.

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

2013-01-01

113

Gingival recession: prevalence and risk indicators among young greek adults  

PubMed Central

Objectives: The aim of the current research was to assess the prevalence of gingival recession and to investigate possible associations among this condition, periodontal and epidemiological variables in a sample of young Greek adults in a general dental practice. Material and Methods: A total of 1,430 young adults was examined clinically and interviewed regarding several periodontal and epidemiological variables. Collected data included demographic variables, oral hygiene habits and smoking status. Clinical examination included the recording of dental plaque, supragingival calculus presence, gingival status and buccal gingival recession. Multivariate logistic regression analysis model was performed to access the possible association between gingival recession and several periodontal and epidemiological variables as potential risk factors. Results: The overall prevalence of gingival recession was 63.9%. The statistical analysis indicated that higher educational level [OR= 2.12, 95% CI= 0.53-8.51], cigarette smoking [OR= 1.97, 95% CI= 1.48-7.91], frequent tooth brushing [OR= 0.98, 95% CI= 0.56-1.96], presence of oral piercing [OR= 0.92, 95% CI= 0.38-1.58], presence of gingival inflammation [OR= 4.54, 95% CI= 1.68-7.16], presence of dental plaque [OR= 1.67, 95% CI= 0.68-2.83] and presence of supragingival calculus [OR=1.34, 95% CI= 0.59-1.88], were the most important associated factors of gingival recession. Conclusions: The observations of the current research supported the results from previous authors that several periodontal factors, educational level and smoking were significantly associated with the presence of gingival recession, while presence of oral piercing was a new factor that was found to be associated with gingival recession. Key words:Gingival recession, prevalence, risk factors, young adults. PMID:25136424

2014-01-01

114

Spectral analysis of stellar light curves by means of neural networks  

NASA Astrophysics Data System (ADS)

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.

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

1999-06-01

115

Z curve theory-based analysis of the dynamic nature of nucleosome positioning in Saccharomyces cerevisiae.  

PubMed

Nucleosome is the elementary structural unit of eukaryotic chromatin. Instability of nucleosome positioning plays critical roles in chromatin remodeling in differentiation and disease. In this study, we investigated nucleosome dynamics in the Saccharomyces cerevisiae genome using a geometric model based on Z curve theory. We identified 52,941 stable nucleosomes and 7607 dynamic nucleosomes, compiling them into a genome-wide nucleosome dynamic positioning map and constructing a user-friendly visualization platform (http://bioinfo.hrbmu.edu.cn/nucleosome). Our approach achieved a sensitivity of 90.31% and a specificity of 87.76% for S. cerevisiae. Analysis revealed transcription factor binding sites (TFBSs) were enriched in linkers. And among the sparse nucleosomes around TFBSs, dynamic nucleosomes were slightly preferred. Gene Ontology (GO) enrichment analysis indicated that stable and dynamic nucleosomes were enriched on genes involved in different biological processes and functions. This study provides an approach for comprehending chromatin remodeling and transcriptional regulation of genes. PMID:23958656

Wu, Xueting; Liu, Hui; Liu, Hongbo; Su, Jianzhong; Lv, Jie; Cui, Ying; Wang, Fang; Zhang, Yan

2013-11-01

116

Efficient broken line fitting procedure for analysis of force spectroscopy curves in chemical force microscopy  

NASA Astrophysics Data System (ADS)

The procedure for the analysis of force-distance curves in chemical force microscopy is presented. This procedure is based upon the Broken Line Fitting algorithm with an adaptation of knots positions. The strength of this method relies on the fact that it has O(N) complexity, which means that it is as efficient as standard peak detection techniques utilized by commercially available software. It is shown by means of computer simulations that the algorithm is able to detect snap-out points of a height comparable to a noise level, which is a significant improvement in comparison to previously reported techniques. The proposed method is also resistant to base line distortions. Using this procedure for an analysis of CH3-CH3 interactions enabled measurements of interactions between only two molecules, which has been confirmed experimentally. The obtained results strongly support validity of the Johnson-Kendall-Roberts model at the sub-nanometer scale.

Jó?wiak, G.; Masalska, A.; Gotszalk, T.; Schroeder, G.

2013-08-01

117

The BVRI Light Curves And Period Analysis Of The Beta Lyrae System XX Leonis  

E-print Network

The contact eclipsing binary system XX Leonis (P = 0.97 days, sp A8) has been analysed using the PHOEBE programme, based on the Wilson Devinney code. The BVRI light curves were obtained during spring 2006 using the 20-cm telescope and ST-7 CCD detector. The effective temperature of the primary component determined from the photometric analysis is T=(7889+/-61)K, the inclination of the orbit is i=(89.98+/-2.45)deg and the photometric mass ratio q=(0.41+/-0.01). Also the third body hypothesis was suggested, based on the period analysis using 57 minimum times and resulting the period of the third body p3= (52.96+/-0.01)yr, amplitude A=(0.057+/-0.029)d and eccentricity e=(0.79+/-0.08) which gives the minimum mass m3,min=(3.6+/-0.8)M_sun.

P. Zasche; M. Wolf; P. Svoboda

2007-11-19

118

Algebra, Home Mortgages, and Recessions  

ERIC Educational Resources Information Center

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…

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

2009-01-01

119

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

NASA Astrophysics Data System (ADS)

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.

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

2014-11-01

120

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

NASA Astrophysics Data System (ADS)

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.

Maess, Matthias; Wagner, Nils; Gaul, Lothar

2006-09-01

121

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

NASA Technical Reports Server (NTRS)

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.

Jegley, Dawn C.

1993-01-01

122

Analysis of complex motion patterns using region-based curve analysis  

Microsoft Academic Search

We consider the analysis of complex motion patterns. We propose a new analysis method consisting of two steps. The first step is based on mathematical morphology. It considers the 2D-region in which the pattern resides and yields a symbolic description, allowing for qualitative comparison and interpretation of patterns. This symbolic description can then be used in a second step for

Marcel Worring; Anneke de Win

1996-01-01

123

Original article Autosomal recessive myotonia congenita  

E-print Network

Original article Autosomal recessive myotonia congenita in sheep GA Moore KR Dyer2 RM Dyer DP, which is consistent with the hypothesis of an autosomal recessive gene responsible for the condition is due to an autosomal recessive gene (Ptacek et al, 1993). Myotonic animals are consistently heavily

Paris-Sud XI, Université de

124

Differentiation of infectious bursal disease virus strains using real-time RT-PCR and high resolution melt curve analysis.  

PubMed

Differentiation of infectious bursal disease virus (IBDV) strains is crucial for effective vaccination programs and epidemiological investigations. In this study, a combination of real-time RT-PCR and high resolution melt (HRM) curve analysis was developed for simultaneous detection and differentiation of IBDV strains/isolates. The hypervariable region of VP2 gene was amplified from several IBDV strains and subjected to HRM curve analysis. The method could readily differentiate between classical vaccines/isolates and variants. Analysis of the nucleotide sequence of the amplicons from each strain revealed that each melt curve profile was related to a unique DNA sequence. The real-time RT-PCR HRM curve analysis was also able to differentiate IBDV strains/isolates directly in bursal tissues from field submissions and from vaccinated commercial flocks. The differences between melting peaks generated from IBDV strains were significantly different (P<0.0001) demonstrating the high discriminatory power of this technique. The results presented in this study indicated that real-time RT-PCR followed by HRM curve analysis provides a rapid and robust technique for genotyping IBDV isolates/strains and can contribute to effective control of IBDV outbreaks. PMID:21111004

Ghorashi, Seyed A; O'Rourke, Denise; Ignjatovic, Jagoda; Noormohammadi, Amir H

2011-01-01

125

Clinical and molecular analysis in families with autosomal recessive osteogenesis imperfecta identifies mutations in five genes and suggests genotype-phenotype correlations.  

PubMed

Autosomal recessive osteogenesis imperfecta (AR-OI) is an inherited condition which in recent years has been shown with increasing genetic and clinical heterogeneity. In this article, we performed clinical assessment and sought mutations in patients from 10 unrelated families with AR-OI, one of whom was presented with the additional features of Bruck syndrome (BS). Pathogenic changes were identified in five different genes: three families had mutations in FKBP10, three in SERPINF1, two in LEPRE1, one in CRTAP, and one in PPIB. With the exception of a FKBP10 mutation in the BS case, all changes are novel. Of note, insertion of an AluYb8 repetitive element was detected in exon 6 of SERPINF1. Since the studied patients had variable manifestations and some distinctive features, genotype/phenotype correlations are suggested. PMID:23613367

Caparrós-Martin, José A; Valencia, María; Pulido, Veronica; Martínez-Glez, Victor; Rueda-Arenas, Inmaculada; Amr, Khalda; Farra, Chantal; Lapunzina, Pablo; Ruiz-Perez, Victor L; Temtamy, Samia; Aglan, Mona

2013-06-01

126

Induction Motor Fault Diagnosis Using a Hilbert-Park Lissajou's Curve Analysis and Neural Network-Based Decision  

E-print Network

Induction Motor Fault Diagnosis Using a Hilbert-Park Lissajou's Curve Analysis and Neural Network is simple. This analysis offers an easy interpretation to conclude on the induction motor condition and its with an aim of classifying automatically the various states of the induction motor. This approach was applied

Paris-Sud XI, Université de

127

The evolutionary ecology of dominance-recessivity.  

PubMed

An "adaptive dynamics" modelling approach to the evolution of dominance-recessivity is presented. In this approach, fitness derives from an explicit ecological scenario, and both evolutionary attractivity and invasibility of resident populations are examined. The ecology consists of a within-individual part representing a locus with regulated activity and a between-individual part that is a two-patch soft selection model. Evolutionary freedom is allowed at a single locus. The evolutionary analysis considers directed random walks on trait space, generated by repeated invasions of mutants. The phenotype of an individual is determined by allelic parameters. Mutations can have two effects: they either affect the affinity of the promoter sequence for transcription factors, or they affect the gene product. The dominance interaction between alleles derives from their promoter affinities. Additive genetics is evolutionarily unstable when selection and evolution maintain two alleles in the population. In such a situation, dominance interactions can become stationary and close to additive genetics or they continue to evolve at a very slow pace towards dominance-recessivity. The probability that a specific dominance interaction will evolve depends on the relative mutation rate of promoter compared to gene product and the distribution of mutational effect sizes. Either allele in the dimorphism can become dominant, and dominance-recessivity is always most likely to evolve. Evolution then approaches a population state where every phenotype has maximum viability in one of the two patches. When the within-individual part is replaced by a housekeeping locus that codes for a metabolic enzyme, evolution favours a population of two alleles under the same conditions as for a regulated locus. In the case of a housekeeping gene, however, the evolutionary dynamical system approaches a population state where the heterozygote and only one homozygote phenotype are equivalent to the optimum phenotypes in the two patches. PMID:10373352

Van Dooren, T J

1999-06-21

128

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

SciTech Connect

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.

Ignace, R. [Department of Physics and Astronomy, East Tennessee State University, Johnson City, TN 37663 (United States); Gayley, K. G. [Department of Physics and Astronomy, University of Iowa, Iowa City, IA 52245 (United States); Hamann, W.-R.; Oskinova, L. M. [Institute for Physics and Astronomy, University Potsdam, D-14476 Potsdam (Germany); Huenemoerder, D. P. [Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, 70 Vassar Street, Cambridge, MA 02139 (United States); Pollock, A. M. T. [European Space Agency XMM-Newton Science Operations Centre, European Space Astronomy Centre, Apartado 78, Villanueva de la Cañada, E-28691 Madrid (Spain); McFall, M., E-mail: ignace@etsu.edu [Department of Physics, 191 W. Woodruff Avenue, Ohio State University, Columbus, OH 43210 (United States)

2013-09-20

129

Assessment and evaluation of a curved beam element for use in large deformation three dimensional finite element analysis  

E-print Network

ASSESSMENT AND EVALUATION OF A CURVED BEAM ELEMENT FOR USE IN LARGE DEFORMATION THREE DIMENSIONAL FINITE ELEMENT ANALYSIS A Thesis by DAVID YIU-CHUNG CHAN Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirement for the degree of liSTER OF SCIENCE August 1980 Major Subject: Aerospace Engineering ASSESSMENT AND EVALUATION OF A CURVED BEAM ELEMENT FOR USE IN LARGE DEFORMATION THREE DIMENSIONAL FINITE ELEMENT ANALYSIS A Thesis by DAVID YIU-CHUNG CHAN...

Chan, David Yiu-Chung

2012-06-07

130

In-plane vibrational analysis of rotating curved beam with elastically restrained root  

Microsoft Academic Search

This study analyzes the in-plane free vibration of a rotating curved beam with an elastically restrained root. Neglecting the effects of shear deformation and the Coriolis force, governing differential equations are derived for the coupled bending–extensional vibration of the curved beam using Hamilton's principle and a consistent linearization approach. Explicit relations are constructed to describe the correlation between the axial

Sen-Yung Lee; Jer-Jia Sheu; Shueei-Muh Lin

2008-01-01

131

Product Differentiation by Analysis of DNA Melting Curves during the Polymerase Chain Reaction  

Microsoft Academic Search

A microvolume fluorometer integrated with a thermal cycler was used to acquire DNA melting curves during polymerase chain reaction by fluorescence monitoring of the double-stranded DNA specific dye SYBR Green I. Plotting fluorescence as a function of temperature as the thermal cycler heats through the dissociation temperature of the product gives a DNA melting curve. The shape and position of

Kirk M. Ririe; Randy P. Rasmussen; Carl T. Wittwer

1997-01-01

132

Non-linear steady-state curving analysis of some unconventional rail trucks  

Microsoft Academic Search

Modified railway passenger truck designs are considered to improve the compatibility between dynamic stability and the ability of the vehicle to steer around curves. A comparative study on the non-linear steady-state curving behavior of some unconventional truck designs reveals that a modified truck design in which the primary suspension in the leading axle is different from the trailing axle –

Rao V Dukkipati; S Narayana Swamy

2001-01-01

133

Management of the Spring Snowmelt Recession in Regulated Systems  

NASA Astrophysics Data System (ADS)

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.

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

2013-12-01

134

On the analysis of non-photochemical chlorophyll fluorescence quenching curves: I. Theoretical considerations.  

PubMed

Non-photochemical quenching (NPQ) protects photosynthetic organisms against photodamage by high light. One of the key measuring parameters for characterizing NPQ is the high-light induced decrease in chlorophyll fluorescence. The originally measured data are maximal fluorescence (Fm') signals as a function of actinic illumination time (Fm'(t)). Usually these original data are converted into the so-called Stern-Volmer quenching function, NPQSV(t), which is then analyzed and interpreted in terms of various NPQ mechanisms and kinetics. However, the interpretation of this analysis essentially depends on the assumption that NPQ follows indeed a Stern-Volmer relationship. Here, we question this commonly assumed relationship, which surprisingly has never been proven. We demonstrate by simulation of quenching data that particularly the conversion of time-dependent quenching curves like Fm'(t) into NPQSV(t) is (mathematically) not "innocent" in terms of its effects. It distorts the kinetic quenching information contained in the originally measured function Fm'(t), leading to a severe (often sigmoidal) distortion of the time-dependence of quenching and has negative impact on the ability to uncover the underlying quenching mechanisms and their contribution to the quenching kinetics. We conclude that the commonly applied analysis of time-dependent NPQ in NPQSV(t) space should be reconsidered. First, there exists no sound theoretical basis for this common practice. Second, there occurs no loss of information whatsoever when analyzing and interpreting the originally measured Fm'(t) data directly. Consequently, the analysis of Fm'(t) data has a much higher potential to provide correct mechanistic answers when trying to correlate quenching data with other biochemical information related to quenching. PMID:23458431

Holzwarth, Alfred R; Lenk, Dagmar; Jahns, Peter

2013-06-01

135

Analysis of the configuration of maximum expiratory flow-volume curves.  

PubMed

The ratios of the instantaneous tangent slopes to corresponding chord slopes are sensitive to curvatures of flow-volume curves; and these dimensionless slope ratios, SR, plotted against fractional volumes remaining to be expired, VCf, are sensitive to the shape of flow-volume curves but insenitive to flow or volume magnitudes. SR-VCf curves predicted for lungs which empty homogeneously differ substantially from those predicted for lungs which empty nonhomogeneously, the latter showing systematic increases in SR with VCf which may extend beyond the homogeneous range. SR-VCf curves for some 80 healthy subjects show systematic changes with age (range 6-64 yr), but all are consistent with advanced obstructive lung disease (chronic bronchitis, emphysema, asthma) are consistent with nonhomogeneous emptying, but it does not seem likely that SR-VCf curves will prove useful for detecting early stages of disease. PMID:632154

Mead, J

1978-02-01

136

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

137

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

PubMed Central

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

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

2013-01-01

138

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

NASA Technical Reports Server (NTRS)

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.

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

1998-01-01

139

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

SciTech Connect

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.

Kowalski, Adam F.; Hawley, Suzanne L.; Hilton, Eric J.; Becker, Andrew C.; Sesar, Branimir [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195 (United States); West, Andrew A.; Bochanski, John J. [MIT Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Avenue, Building 37, Cambridge, MA 02139 (United States)], E-mail: kowalski@astro.washington.edu

2009-08-15

140

Analysis of stellar variability based on polynomial fittings of its light curve  

NASA Astrophysics Data System (ADS)

A method for analysis of stellar light curves (LCs), and in principle, time series, is presented here. It is based on polynomial fitting of the LC with increasing polynomial degree M. Two basic parameters from each polynomial fit of are regarded: residual mean square deviation (SD) of the data in respect to the polynomial fit, SM, and the half of the absolute average deviation of the polynomial (PD) in respect to the average of the data, PM. In each cases the maximal regarded polynomial degree L corresponds to the minimal SD, SL. (In practice the polynomial with degree L + 1 produces larger standard deviation because the number of data is not large and the calculation errors accumulate.) We found well pronounced anti-correlations between SM and PM when M changes from 1 to L. The respective slope PD/SD turns out to be a useful quantify parameter of the LC, characterizing the presence of significant coarse details and giving possibilities for classification of LCs.

Georgiev, Ts. B.

2013-09-01

141

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

NASA Astrophysics Data System (ADS)

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.

Yang, Zhichun; Zhou, Jian; Gu, Yingsong

2014-10-01

142

6.RP Games at Recess  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: The students in Mr. Hillâs class played games at recess. $\\hskip30pt$6 boys played soccer $\\hskip30pt$4 girls played soccer $\\hskip30pt$2 boys jumped r...

143

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

NASA Astrophysics Data System (ADS)

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 ?? = 0.0385 ± 0.0069 deg cycle-1, and it corresponds to an apsidal motion period of U = 100.2 ± 18.0 years.

Bulut, ?.; Bulut, A.; Çiçek, C.

2014-10-01

144

Analysis of the Diagnostic Value of Plasma Endothelin for Diabetic Retinopathy Using the Receiver Operating Characteristic Curve  

Microsoft Academic Search

Aim: To investigate the diagnostic efficacy and clinical application value of plasma endothelin-1 for diabetic retinopathy using receiver operating characteristic (ROC) curve analysis. Methods: This was a prospective investigational study. Funduscopy and fundus fluorescein angiography were used as gold standards for the diagnosis of diabetic retinopathy. Plasma endothelin-1 was measured in 96 diabetic patients with retinopathy (the case group) and

Hong Zhu; Cai-Hong Shi

2007-01-01

145

The Obsessive Compulsive Scale of the Child Behavior Checklist Predicts Obsessive-Compulsive Disorder: A Receiver Operating Characteristic Curve Analysis  

ERIC Educational Resources Information Center

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

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

146

Type curve analysis for naturally fractured reservoirs (infinite-acting reservoir case): a new approach  

E-print Network

). A further improvement is presented in this work. This improvement was achieved by the introduction of a new dimensionless parameter, ?=[]C[], where the use of ? as a family parameter for the dimensionless pressure function type curves provides a...

Angel Restrepo, Juan Alejandro

2012-06-07

147

Glow curve analysis applied to the discrimination of X ray versus proton irradiation.  

PubMed

Three types of thermoluminescence dosemeters (TLDs): LiF:Mg,Ti (TLD-100), CaF2:Tm (TLD-300), and alpha-Al2O3:C (TLD-500), were investigated for their glow curve response to separate X ray and proton irradiations. The glow curve structure for each individual TLD's exposure to the X ray and proton irradiations was analysed and compared. Distinguishable differences between the glow curve structure characteristic of each type of radiation were observed. The proton TLD-100 glow curve has revealed a complex high-temperature peak structure that was used for the proton/X ray discrimination algorithm. Proton irradiation of TLD-300 resulted in an apparent switch in the relative heights of peaks 3 and 5 as compared to X ray. In TLD-500, proton irradiation produced a more subtle difference in the glow curve with an increase in the ratio between high- and low-temperature peaks. Results demonstrate promising differences in glow curve structure present allowing for discrimination between X ray and proton radiation field exposures. PMID:12382714

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

2002-01-01

148

An Analysis of the Shapes of Ultraviolet Extinction Curves. IV. Extinction without Standards  

E-print Network

We present a new method for deriving UV-through-IR extinction curves, based on the use of stellar atmosphere models to provide estimates of the intrinsic (i.e., unreddened) stellar spectral energy distributions (SEDs), rather than unreddened (or lightly reddened) standard stars. We show that this ``extinction-without-standards'' technique greatly increases the accuracy of the derived extinction curves and allows realistic estimations of the uncertainties. An additional benefit of the technique is that it simultaneously determines the fundamental properties of the reddened stars themselves, making the procedure valuable for both stellar and interstellar studies. We demonstrate how the extinction-without-standards curves make it possible to: 1) study the uniformity of extinction in localized spatial regions with unprecedented precision; 2) determine the relationships between different aspects of curve morphology; 3) produce high quality extinction curves from low color excess sightlines; and 4) derive reliable extinction curves for mid-late B stars, thereby increasing spatial coverage and allowing the study of extinction in open clusters and associations dominated by such stars. The application of this technique to the available database of UV-through-IR SEDs, and to future observations, will provide valuable constraints on the nature of interstellar grains and on the processes which modify them, and will enhance our ability to remove the multi-wavelength effects of extinction from astronomical energy distributions.

Edward L. Fitzpatrick; Derck Massa

2005-06-17

149

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

NASA Astrophysics Data System (ADS)

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.

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

2005-04-01

150

An analysis of calibration curve models for solid-state heat-flow calorimeters  

SciTech Connect

Various calibration curve models for solid-state calorimeters are compared to determine which model best fits the calibration data. The calibration data are discussed. The criteria used to select the best model are explained. A conclusion regarding the best model for the calibration curve is presented. These results can also be used to evaluate the random and systematic error of a calorimetric measurement. A linear/quadratic model has been used for decades to fit the calibration curves for wheatstone bridge calorimeters. Excellent results have been obtained using this calibration curve model. The Multical software package uses this model for the calibration curve. The choice of this model is supported by 40 years [1] of calorimeter data. There is good empirical support for the linear/quadratic model. Calorimeter response is strongly linear. Calorimeter sensitivity is slightly lower at higher powers; the negative coefficient of the x{sup 2} term accounts for this. The solid-state calorimeter is operated using the Multical [2] software package. An investigation was undertaken to determine if the linear/quadratic model is the best model for the new sensor technology used in the solid-state calorimeter.

Hypes, P. A. (Philip A.); Bracken, D. S. (David S.); McCabe, G. (George)

2001-01-01

151

Seasonal recession of Mars' south polar cap in 1986  

NASA Technical Reports Server (NTRS)

Photographs of Mars obtained during the 1986 opposition of the planet have been used to derive the regression curve for the south polar cap between Ls = 190 deg and Ls = 255 deg. The 1986 regression appears to have been unexceptional until after Ls = 230 deg, when it becomes retarded relative to the normal established by the 1971 and 1977 regressions. A study of the data as a function of the filter used suggests that circumpolar clouds were present in early spring, unlike the case in the 1977 recession.

James, Philip B.; Martin, Leonard J.; Henson, Jean R.; Birch, Peter V.

1990-01-01

152

The mathematical analysis for peristaltic flow of nano fluid in a curved channel with compliant walls  

NASA Astrophysics Data System (ADS)

In the present paper, we have investigated the peristaltic flow of nano fluid in a curved channel with compliant walls. The governing equations of nano fluid model for curved channel are derived including the effects of curvature. The highly nonlinear partial differential equations are simplified using the long wave length and low Reynolds number assumptions. The reduced nonlinear partial differential equation is solved analytically with the help of homotopy perturbation method. The physical features of pertinent parameters have been discussed by plotting the graphs of pressure rise, velocity, temperature, nano particle volume fraction and stream functions.

Nadeem, S.; Maraj, E. N.

2014-01-01

153

Curved Mirrors  

NSDL National Science Digital Library

This inquiry activity will be used before discussing curved mirrors in class. Students will discover how curved mirrors act and how the size and the orientation of the image are related to the distance from the mirror. Ray diagrams for curved mirrors are

Horton, Michael

2009-05-30

154

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

NASA Astrophysics Data System (ADS)

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.

Kato, Taichi; Maehara, Hiroyuki

2013-08-01

155

Curve fitting method for modeling and analysis of photovoltaic cells characteristics  

Microsoft Academic Search

This paper deals with the mathematical model to assess the performances of photovoltaic (PV) cells. The PV system characteristics are modeled and analyzed by using the curve fitting method referred to the different connections of PV cells and different solar irradiance. The results are compared with those resulting from measured data in a real case. Specific LabVIEW™ and Matlab™ software

H. Andrei; T. Ivanovici; G. Predusca; E. Diaconu; P. C. Andrei

2012-01-01

156

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

ERIC Educational Resources Information Center

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…

Johnson, Ursula Y.; Hull, Darrell M.

2014-01-01

157

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

PubMed

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

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

2006-01-01

158

Recurrence plot analysis of nonstationary data: The understanding of curved patterns  

Microsoft Academic Search

Recurrence plots of the calls of the Nomascus concolor (Western black crested gibbon) and Hylobates lar (White-handed gibbon) show characteristic circular, curved, and hyperbolic patterns superimposed to the main temporal scale of the signal. It is shown that these patterns are related to particular nonstationarities in the signal. Some of them can be reproduced by artificial signals like frequency modulated

A. Facchini; H. Kantz; E. Tiezzi

2005-01-01

159

Numerical Investigation of the Fluid Flow in Continuous Casting Tundish Using Analysis of RTD Curves  

Microsoft Academic Search

A detailed mathematical procedure of the optimization of the fluid flow in a tundish water model with and without flow control devices (weir and dam) was carried out using the commercial CFD code FLUENT 6. 0. The (k-?) two-equation model was used to model turbulence. The residence time distribution (RTD) curves were used to analyze the behavior of the flow

Bensouici Moumtez; Ahmed Bellaouar; Kamel Talbi

2009-01-01

160

Analysis of coupling between a curved FSS and an enclosed planar dipole array  

Microsoft Academic Search

Interaction between an antenna and an enclosing FSS is investigated using the Pocklington equation approach from an earlier study of arbitrarily curved free-standing arrays of dipoles. Part of such a collection of elements can be regarded as a receiving antenna, and the rest can be distributed around it to form a dichroic enclosure. It is then possible to analyse this

E. A. Parker; B. Philips; R. J. Langley

1995-01-01

161

A Study of Decline Curve Analysis in the Elm Coulee Field  

E-print Network

and SEPD methods such that once boundary-dominated flow begins the decline is described by an Arps curve with a b-value of 0.3. What I found from hindcasting was that early production history, up to six months, is generally detrimental to accurate...

Harris, Seth C

2013-08-22

162

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

NASA Astrophysics Data System (ADS)

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.

Simonovi?, N. S.; Solov'ev, E. A.

2013-05-01

163

Learning curve analysis of robot-assisted radical hysterectomy for cervical cancer: initial experience at a single institution  

PubMed Central

Objective The aim of this study was to evaluate the learning curve and perioperative outcomes of robot-assisted laparoscopic procedure for cervical cancer. Methods A series of 65 cases of robot-assisted laparoscopic radical hysterectomies with bilateral pelvic lymph node dissection for early stage cervical cancer were included. Demographic data and various perioperative parameters including docking time, console time, and total operative time were reviewed from the prospectively collected database. Console time was set as a surrogate marker for surgical competency, in addition to surgical outcomes. The learning curve was evaluated using cumulative summation method. Results The mean operative time was 190 minutes (range, 117 to 350 minutes). Two unique phases of the learning curve were derived using cumulative summation analysis; phase 1 (the initial learning curve of 28 cases), and phase 2 (the improvement phase of subsequent cases in which more challenging cases were managed). Docking and console times were significantly decreased after the first 28 cases compared with the latter cases (5 minutes vs. 4 minutes for docking time, 160 minutes vs. 134 minutes for console time; p<0.001 and p<0.001, respectively). There was a significant reduction in blood loss during operation (225 mL vs. 100 mL, p<0.001) and early postoperative complication rates (28% vs. 8.1%, p=0.003) in phase 2. No conversion to laparotomy occurred. Conclusion Improvement of surgical performance in robot-assisted surgery for cervical cancer can be achieved after 28 cases. The two phases identified by cumulative summation analysis showed significant reduction in operative time, blood loss, and complication rates in the latter phase of learning curve. PMID:24167665

Yim, Ga Won; Kim, Sang Wun; Nam, Eun Ji; Kim, Sunghoon

2013-01-01

164

Parametric Curves parametric curves (Splines)  

E-print Network

curves (Splines) · polygonal meshes #12;2 Roller coaster · Next programming assignment involves creating a 3D roller coaster animation · We must model the 3D curve describing the roller coaster, but how

Treuille, Adrien

165

Fourier Analysis of Gamma-Ray Burst Light Curves: Searching for Direct Signature of Cosmological Time Dilation  

E-print Network

We study the power density spectrum (PDS) of light curves of the observed gamma-ray bursts (GRBs) to search for a direct signature for cosmological time dilation in the PDS statistics with the GRBs whose redshifts $z$'s are known. The anticorrelation of a timescale measure and a brightness measure is indirect evidence of its effect. On the other hand, we directly demonstrate that a time dilation effect can be seen in GRB light curves. We find that timescales tend to be shorter in bursts with small redshift, as expected from cosmological time-dilation effects, and we also find that there may be non-cosmological effects constituting to this correlation. We discuss its implication on interpretations of the PDS analysis results. We put forward another caution to this kind of analysis when we statistically exercise with GRBs whose $z$ is unknown.

Heon-Young Chang

2001-06-13

166

High-Resolution Melting Curve Analysis, a Rapid and Affordable Method for Mutation Analysis in Childhood Acute Myeloid Leukemia  

PubMed Central

Background: Molecular genetic alterations with prognostic significance have been described in childhood acute myeloid leukemia (AML). The aim of this study was to establish cost-effective techniques to detect mutations of FMS-like tyrosine kinase 3 (FLT3), nucleophosmin 1 (NPM1), and a partial tandem duplication within the mixed-lineage leukemia (MLL-PTD) genes in childhood AML. Procedure: Ninety-nine children with newly diagnosed AML were included in this study. We developed a fluorescent dye SYTO-82 based high-resolution melting (HRM) curve analysis to detect FLT3 internal tandem duplication (FLT3-ITD), FLT3 tyrosine kinase domain (FLT3-TKD), and NPM1 mutations. MLL-PTD was screened by real-time quantitative PCR. Results: The HRM methodology correlated well with gold standard Sanger sequencing with less cost. Among the 99 patients studied, the FLT3-ITD mutation was associated with significantly worse event-free survival (EFS). Patients with the NPM1 mutation had significantly better EFS and overall survival. However, HRM was not sensitive enough for minimal residual disease monitoring. Conclusion: High-resolution melting was a rapid and efficient method for screening of FLT3 and NPM1 gene mutations. It was both affordable and accurate, especially in resource underprivileged regions. Our results indicated that HRM could be a useful clinical tool for rapid and cost-effective screening of the FLT3 and NPM1 mutations in AML patients. PMID:25250304

Liu, Yin; Tang, Jingyan; Wakamatsu, Peter; Xue, Huiliang; Chen, Jing; Gaynon, Paul S.; Shen, Shuhong; Sun, Weili

2014-01-01

167

Analysis of a New Variational Model to Restore Point-Like and Curve-Like Singularities in Imaging  

SciTech Connect

The paper is concerned with the analysis of a new variational model to restore point-like and curve-like singularities in biological images. To this aim we investigate the variational properties of a suitable energy which governs these pathologies. Finally in order to realize numerical experiments we minimize, in the discrete setting, a regularized version of this functional by fast descent gradient scheme.

Aubert, Gilles, E-mail: gaubert@unice.fr [Universite de Nice Sophia Antipolis, Laboratoire J.A. Dieudonne (France)] [Universite de Nice Sophia Antipolis, Laboratoire J.A. Dieudonne (France); Blanc-Feraud, Laure, E-mail: Laure.Blanc-Feraud@inria.fr; Graziani, Daniele, E-mail: Daniele.Graziani@inria.fr [Inria, Morpheme CNRS/INRIA/UNSA Sophia Antipolis (France)] [Inria, Morpheme CNRS/INRIA/UNSA Sophia Antipolis (France)

2013-02-15

168

The data mining: An analysis of 20 eclipsing binary light-curves observed by the INTEGRAL/OMC  

E-print Network

Twenty eclipsing binaries were selected for an analysis from a huge database of observations made by the INTEGRAL/OMC camera. The photometric data were processed and analyzed, resulting in a first light-curve study of these neglected eclipsing binaries. Most of the selected systems are the detached ones. The system ET Vel was discovered to be an eccentric one. Due to missing spectroscopic study of these stars, further detailed analyses are still needed.

P. Zasche

2008-11-11

169

Estimation of kinetic parameters by progress curve analysis for the synthesis of ( R)-mandelonitrile by Prunus amygdalus hydroxynitrile lyase  

Microsoft Academic Search

Consistent sets of kinetic parameters were estimated for the synthesis of (R)-mandelonitrile, catalyzed by Prunus amygdalus hydroxynitrile lyase, at 5 and 25°C and pH 5.5 by progress curve analysis. The rate constants and equilibrium constants of the nonenzymatic reaction were determined separately to reduce the number of parameters to be estimated simultaneously. At a lower temperature the equilibrium is much

W. F Willeman; U Hanefeld; A. J. J Straathof; J. J Heijnen

2000-01-01

170

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

NASA Technical Reports Server (NTRS)

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.

Ko, William L.

1999-01-01

171

Investment Cost Analysis for Key Industries of New Energy Based on Boston Experience Curve  

Microsoft Academic Search

\\u000a Based on the Boston Experience Curve model, the article analyzes China’s new energy key industry – wind power industry investment\\u000a and find that wind power industry has greater development potentiality in China, and the learning rate of China’s wind power\\u000a is less than the developed countries learning scope, the cost and price of wind power will turn down with the

Yuanying Chi; Benkun Chi; Xiangyang Li; Dongxiao Niu

172

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

SciTech Connect

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.

Quintana, Elisa V.; Rowe, Jason F.; Caldwell, Douglas A.; Christiansen, Jessie L.; Jenkins, Jon M.; Morris, Robert L.; Smith, Jeffrey C.; Thompson, Susan E. [SETI Institute, 189 Bernardo Ave, Suite 100, Mountain View, CA 94043 (United States); Barclay, Thomas [Bay Area Environmental Research Institute/NASA Ames Research Center, Moffett Field, CA 94035 (United States); Howell, Steve B.; Borucki, William J.; Sanderfer, Dwight T.; Still, Martin [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Ciardi, David R. [NASA Exoplanet Science Institute/Caltech, 770 South Wilson Ave., MC 100-2, Pasadena, CA 91125 (United States); Demory, Brice-Olivier [Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Klaus, Todd C. [Orbital Sciences Corporation/NASA Ames Research Center, Moffett Field, CA 94035 (United States); Fulton, Benjamin J.; Shporer, Avi, E-mail: elisa.quintana@nasa.gov [Las Cumbres Observatory Global Telescope Network, 6740 Cortona Drive, Suite 102, Santa Barbara, CA 93117 (United States)

2013-04-20

173

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

NASA Technical Reports Server (NTRS)

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.

Bookout, P. S.

1995-01-01

174

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

SciTech Connect

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.

Fitzpatrick, E. L. [Department of Astronomy and Astrophysics, Villanova University, 800 Lancaster Avenue, Villanova, PA 19085 (United States); Massa, D. [SGT, Inc., Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States)], E-mail: edward.fitzpatrick@villanova.edu, E-mail: massa@derckmassa.net

2009-07-10

175

Control of the Photosynthetic Apparatus of Acetabularia mediterranea by Blue Light : Analysis by Light-Saturation Curves.  

PubMed

During growth, Acetabularia mediterranea requires the action of blue light to maintain high rates of photosynthesis. In the present study, blue light-dependent alterations of the photosynthetic apparatus, which can be detected by analysis of light-saturation curves and by measurements of partial reactions of the photosynthetic electron transport chain, are described. Light-saturation curves of photosynthesis in vivo were measured with a new closed oxygen electrode system after culture of Acetabularia in continuous red or blue light. These curves were compared to those of 2,6-dichlorophenol-indophenol reduction by isolated chloroplast membranes. The analysis lead to the following statements: (a) only one reaction limits electron transport rates in vitro (dichlorophenol-indophenol reduction) at all light intensities irrespective of the light quality during growth, and (b) the limiting step is light driven and located in the reaction center of photosystem II. Presumably, this same reaction determines the flow of electrons under low light intensities in vivo in cells from white, blue, and red light. In addition to photosynthesis, the rates of dark respiration changed due to the action of blue light. Concomitantly, the light compensation point of apparent photosynthesis was shifted during monochromatic irradiations. PMID:16665593

Wennicke, H; Schmid, R

1987-08-01

176

Highly curved bowl-shaped fragments of fullerenes: synthesis, structural analysis, and physical properties.  

PubMed

Highly curved buckybowls 3, 4, and 5 were synthesized from planar precursors, fluoranthenes 8, benzo[k]fluoranthenes 10 and naphtho[1,2-k]-cyclopenta[cd]fluoranthenes 12, respectively, using straightforward palladium-catalyzed cyclization reactions. These fluoranthene-based starting materials were easily prepared from 1,8-bis(arylethynyl)naphthalenes 6. Both buckybowls 3 and 4 are fragments of C60 , whereas 5 is a unique subunit of C70 . The curved structures were identified by X-ray crystallography, and they are deep bowls. The maximum ?-orbital axis vector (POAV) pyramidalization angle in both 3 and 4 is 12.8°. Such a high curvature is very rarely obtained. Buckybowls 5 are less curved than the others because they have a lower density of five-membered rings, analogous to the tube portion of C70 . Cyclopentaannulation increases the bowl depths of 3 and 4, but not the maximum POAV pyramidalization angle. Among the eight buckybowls studied herein, five form polar crystals. The bowl-to-bowl inversion dynamics of these buckybowls can be classified into two types; one has a planar transition structure, whereas the other has an S-shaped transition structure. A larger longitudinal length of these buckybowls corresponds to a stronger preference for the latter. The photophysical properties of these buckybowls were examined and compared with those of C60 and C70 . Buckybowls 5 have absorption bands at wavelengths greater than 450?nm, which are similar to those of C70 . The chiral resolution of the mono-substituted buckybowl 4?ac was also studied by using HPLC with a chiral column. PMID:24311153

Chen, Min-Kuan; Hsin, Hsin-Ju; Wu, Tsun-Cheng; Kang, Bo-Yan; Lee, Yen-Wei; Kuo, Ming-Yu; Wu, Yao-Ting

2014-01-01

177

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

SciTech Connect

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.

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

2005-08-12

178

Determination of pull-off forces of textured silicon surfaces by AFM force curve analysis  

NASA Astrophysics Data System (ADS)

This paper presents a novel methodology to measure the pull-off force of rigid bodies by recording force curves with an atomic force microscope (AFM). With the presented method, structured or modified surfaces can be inspected under close to target device conditions. Furthermore, large sample arrays can be inspected using the AFM as a sensing element. The inspected structures in this study are rigid silicon discs with a diameter of 200 µm, supported by soft silicon oxide springs. The discs are pushed down by the AFM tip on a bottom substrate. When retracting the AFM tip and the disc, a discontinuity in the force curve of the AFM occurs due to the pull-off. The surface interaction of silicon oxide surfaces provided with hemispherical tips and flat silicon surfaces is determined. Therefore, various surface configurations are inspected, with varying tip radii and varying number of tips. The lowest adhesion force measured for a single device is 240 nN. In terms of total work of adhesion per area this value equals 9 × 10-7 mJ m-2. The measured adhesion is compared to calculated data based on a Van der Waals surface interaction model. The method features a relative error of 0.26 which is comparable to the corresponding value of cantilever beam detachment (CBD) measurements from the literature. The resolution of the presented method is only limited by the force resolution of the AFM which in this work is 20 nN.

Bachmann, Daniel; Hierold, Christofer

2007-07-01

179

Predicting U.S. Recessions: Financial Variables As Leading Indicators  

Microsoft Academic Search

This paper examines the out-of-sample performance of various financial variables as predictors of U.S. recessions. Series such as interest rates and spreads, stock prices, and monetary aggregates are evaluated individually and in comparison with other financial and nonfinancial indicators. The analysis focuses on out-of-sample performance from one to eight quarters ahead. Results show that stock prices are useful with one-

Arturo Estrella; Frederic S. Mishkin

1998-01-01

180

Fr\\'echet means of curves for signal averaging and application to ECG data analysis  

E-print Network

Signal averaging is the process that consists in computing a mean shape from a set of noisy signals. In the presence of geometric variability in time in the data, the usual Euclidean mean of the raw data yields a mean pattern that does not reflect the typical shape of the observed signals. In this setting, it is necessary to use alignment techniques for a precise synchronization of the signals, and then to average the aligned data to obtain a consistent mean shape. In this paper, we study the numerical performances of Fr\\'echet means of curves which are extensions of the usual Euclidean mean to spaces endowed with non-Euclidean metrics. This yields a new algorithm for signal averaging without a reference template. We apply this approach to the estimation of a mean heart cycle from ECG records.

Bigot, Jérémie

2011-01-01

181

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

USGS Publications Warehouse

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

Kipp, Jr, K. L.

1985-01-01

182

p-Version curved shell element for geometrically nonlinear analysis of laminated composite plates and shells  

SciTech Connect

This paper presents a p-version geometrically nonlinear formulation for laminated composites based on the total Lagrangian approach for a nine node three dimensional curved shell element. The element displacement approximation can be of arbitrary and different polynomial orders in the plane of the element and in the transverse direction. The element approximation functions are derived from the Lagrange family of interpolation functions and ensure C{degree} continuity. The lamina properties are incorporated by numerically integrating the element stiffness matrix for each lamina. Complete three dimensional stresses and strains are considered. Incremental equations of equilibrium are derived and solved using the standard Newton-Raphson method. Numerical examples are presented to show the accuracy, efficiency and advantages of the present formulation.

Sorem, R.M.; Surana, K.S. [Univ. of Kansas, Lawrence, KS (United States). Dept. of Mechanical Engineering

1997-07-01

183

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

NASA Technical Reports Server (NTRS)

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.

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

1981-01-01

184

Acoustic emission analysis of full-scale honeycomb sandwich composite curved fuselage panels  

NASA Astrophysics Data System (ADS)

Acoustic emission (AE) was monitored in notched full-scale honeycomb sandwich composite curved fuselage panels during loading. The purpose of the study was to evaluate the AE technique as a tool for detecting notch tip damage initiation and evaluating damage severity in such structures. This evaluation was a part of a more general study on the damage tolerance of six honeycomb sandwich composite curved panels, each containing a different damage scenario. The overall program objective was to investigate the effects of holes and notches on residual strength. The investigation was conducted using the Full-Scale Aircraft Structural Test Evaluation and Research (FASTER) facility located at the Federal Aviation Administration William J. Hughes Technical Center, Atlantic City International Airport, NJ. This paper reports on the AE results recorded during the loading to failure of two selected panels. The results show that damage initiation at the tips of the notches, and its progression along the panel, could be detected and located. These AE results were correlated with the deformation and strain fields measured through strain photogrammetry, throughout loading, at the vicinity of these notches. This correlation aided in interpreting the AE results. While the fretting among the newly created fracture surfaces generated a large number of low-intensity AE signals, the high-intensity signals generated at high load levels provided a good measure for anticipating incipient fracture. Further, the AE results located internal disbonding caused during panel fabrication. The large number of low-intensity AE signals generated from the disbonded regions was associated with the fretting among the disbonded surfaces.

Leone, Frank A., Jr.; Ozevin, Didem; Godinez, Valery; Mosinyi, Bao; Bakuckas, John G., Jr.; Awerbuch, Jonathan; Lau, Alan; Tan, Tein-Min

2008-03-01

185

Estimation of kinetic parameters by progress curve analysis for the synthesis of (R)-mandelonitrile by Prunus amygdalus hydroxynitrile lyase.  

PubMed

Consistent sets of kinetic parameters were estimated for the synthesis of (R)-mandelonitrile, catalyzed by Prunus amygdalus hydroxynitrile lyase, at 5 and 25 degrees C and pH 5.5 by progress curve analysis. The rate constants and equilibrium constants of the nonenzymatic reaction were determined separately to reduce the number of parameters to be estimated simultaneously. At a lower temperature the equilibrium is much more favorable and the formation of rac-mandelonitrile by the nonenzymatic reaction is suppressed. The estimated kinetic parameters were used to identify that the rate determining step in the catalytic cycle is the release of (R)-mandelonitrile from the ternary complex. PMID:10938422

Willeman; Hanefeld; Straathof; Heijnen

2000-09-01

186

A TRANSIT TIMING ANALYSIS OF NINE RISE LIGHT CURVES OF THE EXOPLANET SYSTEM TrES-3  

SciTech Connect

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.

Gibson, N. P.; Pollacco, D.; Simpson, E. K.; Barros, S.; Joshi, Y. C.; Todd, I.; Keenan, F. P. [Astrophysics Research Centre, School of Mathematics and Physics, Queen's University, University Road, Belfast, BT7 1NN (United Kingdom); Skillen, I.; Benn, C. [Isaac Newton Group of Telescopes, Apartado de Correos 321, E-38700 Santa Cruz de la Palma, Tenerife (Spain); Christian, D. [Physics and Astronomy Department, California State University Northridge, Northridge, California 91330-8268 (United States); Hrudkova, M. [Astronomical Institute, Charles University Prague, V Holesovickach 2, CZ-180 00 Praha (Czech Republic); Steele, I. A. [Astrophysics Research Institute, Liverpool John Moores University, CH61 4UA (United Kingdom)], E-mail: ngibson07@qub.ac.uk

2009-08-01

187

Quantitative summaries of treatment effect estimates obtained with network meta-analysis of survival curves to inform decision-making  

PubMed Central

Background Increasingly, network meta-analysis (NMA) of published survival data are based on parametric survival curves as opposed to reported hazard ratios to avoid relying on the proportional hazards assumption. If a Bayesian framework is used for the NMA, rank probabilities associated with the alternative treatments can be obtained, which directly support decision-making. In the context of survival analysis multiple treatment effect measures are available to inform the rank probabilities. Methods A fractional polynomial NMA of overall survival in advanced melanoma was performed as an illustrative example. Rank probabilities were calculated and presented for the following effect measures: 1) median survival; 2) expected survival; 3) mean survival at the follow-up time point of the trial with the shortest follow-up; 4) hazard or hazard ratio over time; 5) cumulative hazard or survival proportions over time; and 6) mean survival at subsequent time points. The advantages and disadvantages of the alternative measures were discussed. Results Since hazard and survival estimates may vary over time for the compared interventions, calculations of rank probabilities for an NMA of survival curves may depend on the effect measure. With methods 1–3 rank probabilities do not vary over time, which are easier to understand and communicate than rank probabilities that vary over time as obtained with methods 4–6. However, rank probabilities based on methods 4–6 provide useful information regarding the relative treatment effects over time. Conclusions Different approaches to summarize results of a NMA of survival curves with rank probabilities have pros and cons. Rank probabilities of treatment effects over time provide a more transparent and informative approach to help guide decision-making than single rank probabilities based on collapsed measures, such as median survival or expected survival. Rank probabilities based on survival proportions are the most intuitive and straightforward to communicate, but alternatives based on the hazard function or mean survival over time may also be useful. PMID:24289277

2013-01-01

188

Rapid detection of Dirofilaria immitis in mosquito vectors and dogs using a real-time fluorescence resonance energy transfer PCR and melting curve analysis  

Microsoft Academic Search

A real-time fluorescence resonance energy transfer (FRET) PCR supplemented with melting curve analysis for the rapid molecular detection of Dirofilaria immitis in mosquito vectors and dog blood samples was developed. This real-time FRET PCR was based on the fluorescence melting curve analysis of a hybrid between an amplicon generated from the D. immitis ribosomal RNA gene sequence and specific fluorophore-labeled

Tongjit Thanchomnang; Pewpan M. Intapan; Viraphong Lulitanond; Somboon Sangmaneedet; Sudchit Chungpivat; Piyanan Taweethavonsawat; Wej Choochote; Wanchai Maleewong

2010-01-01

189

Bayesian Analysis of Multivariate Latent Curve Models With Nonlinear Longitudinal Latent Effects  

PubMed Central

In longitudinal studies, investigators often measure multiple variables at multiple time points and are interested in investigating individual differences in patterns of change on those variables. Furthermore, in behavioral, social, psychological, and medical research, investigators often deal with latent variables that cannot be observed directly and should be measured by 2 or more manifest variables. Longitudinal latent variables occur when the corresponding manifest variables are measured at multiple time points. Our primary interests are in studying the dynamic change of longitudinal latent variables and exploring the possible interactive effect among the latent variables. Much of the existing research in longitudinal studies focuses on studying change in a single observed variable at different time points. In this article, we propose a novel latent curve model (LCM) for studying the dynamic change of multivariate manifest and latent variables and their linear and interaction relationships. The proposed LCM has the following useful features: First, it can handle multivariate variables for exploring the dynamic change of their relationships, whereas conventional LCMs usually consider change in a univariate variable. Second, it accommodates both first- and second-order latent variables and their interactions to explore how changes in latent attributes interact to produce a joint effect on the growth of an outcome variable. Third, it accommodates both continuous and ordered categorical data, and missing data. PMID:20016757

Song, Xin-Yuan; Lee, Sik-Yum; Hser, Yih-Ing

2009-01-01

190

A semi-micromechanic interlaminar strain analysis on curved-beam specimens  

NASA Technical Reports Server (NTRS)

Experimental analyses were performed for determination of interlaminar strains in circumferentially unidirectional curved beam specimens. Semi-circular and semi-elliptic carbon-epoxy specimens were subjected to opening mode tensile loadings. Whole field measurements were recorded at load levels from about 5 to more than 90 pct of failure loads. Contour maps of displacement fields were obtained by using moire interferometry, using reference gratings of 2400 lines/mm or 60,690 lines/in. Whole field contour maps of circumferential and interlaminar strains were obtained by using moire interferometry in a semi-micromechanic scale. Various anomalous effects were observed in the displacement fields. The zig-zag fringe patterns indicated that the fiber orientation in each layer was not truly circumferential. This deviation from the unidirectionality caused free-edge effects, such as interlaminar shear strains even at the axis of symmetry and the altered normal strains in the thickness direction. In the resin rich zones between layers, the tensile interlaminar strain was excessively large due to the large compliance. As the result of the combined effect of these anomalous behaviors, the values of the interlaminar tensile strains were larger than those predicted analytically. The modulus E sub 3 was actually smaller than the assumed value E sub 2 by 20 pct.

Joh, Duksung

1990-01-01

191

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

NASA Technical Reports Server (NTRS)

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.

Lake, Mark S.

1989-01-01

192

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

NASA Astrophysics Data System (ADS)

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.

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

2014-07-01

193

Development of Curved-Plate Elements for the Exact Buckling Analysis of Composite Plate Assemblies Including Transverse Shear Effects  

NASA Technical Reports Server (NTRS)

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.

McGowan, David M.; Anderson, Melvin S.

1998-01-01

194

Kinetic studies on the enzyme (S)-hydroxynitrile lyase from hevea brasiliensis using initial rate methods and progress curve analysis  

PubMed

(S)-Hydroxynitrile lyase (EC 4.1.2.39) from Hevea brasiliensis(rubber tree) catalyzes the reversible cleavage of cyanohydrins to aldehydes or ketones and prussic acid (HCN). Enzyme kinetics in both directions was studied on a model system with mandelonitrile, benzaldehyde, and HCN using two different methods-initial rate measurements and progress curve analysis. To discriminate between possible mechanisms with the initial rate method, product inhibition was studied. Benzaldehyde acts as a linear competitive inhibitor against mandelonitrile whereas HCN shows S-linear I-parabolic mixed-type inhibition. These results indicate an Ordered Uni Bi mechanism with the formation of a dead-end complex of enzyme, (S)-mandelonitrile and HCN. Prussic acid is the first product released from the enzyme followed by benzaldehyde. For progress curve analysis, a kinetic model of an Ordered Uni Bi mechanism including a dead-end complex, enzyme inactivation, and the chemical parallel reaction was set up, which described the experimental values very well. From the reaction rates obtained the kinetic constants were calculated and compared with the ones obtained from the initial rate method. Good agreement could be achieved between the two methods supporting the suggested mechanism. Copyright 1999 John Wiley & Sons, Inc. PMID:10099509

Bauer; Griengl; Steiner

1999-01-01

195

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)

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

Adamovic, Marko; Braud, Isabelle; Branger, Flora; Krier, Robert

2013-04-01

196

The impact of the great recession on community-based mental health organizations: an analysis of top managers' perceptions of the economic downturn's effects and adaptive strategies used to manage the consequences in Ohio.  

PubMed

The Great Recession of 2007-2009 adversely affected the financial stability of the community-based mental health infrastructure in Ohio. This paper presents survey results of the type of adaptive strategies used by Ohio community-based mental health organizations to manage the consequences of the economic downturn. Results were aggregated into geographical classifications of rural, mid-sized urban, and urban. Across all groups, respondents perceived, to varying degrees, that the Great Recession posed a threat to their organization's survival. Urban organizations were more likely to implement adaptive strategies to expand operations while rural and midsized urban organizations implemented strategies to enhance internal efficiencies. PMID:23408296

Sweeney, Helen Anne; Knudsen, Kraig

2014-04-01

197

Surface recession characteristics of a cryogenic insulation subjected to arc-tunnel heating  

NASA Technical Reports Server (NTRS)

Specimens of a cryogenic insulation, proposed for use on the space shuttle external tank, were tested in an arc tunnel over a range of heating rates, pressures, and enthalpies corresponding to the shuttle ascent environment. A regression analysis was used to correlate the test data. Correlation equations involving surface recession rate as a function of heating rate, pressure, and enthalpy were developed. These equations can be used to make total surface recession predictions for shuttle ascent flight environments.

Pittman, C. M.; Brown, R. D.

1975-01-01

198

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

Microsoft Academic Search

The hot compression behavior of a 17-4 PH stainless steel (AISI 630) has been investigated at temperatures of 950 °C to 1150 °C\\u000a 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\\u000a data analysis in the hot compression test was given. The work hardening rate analysis

Hamed Mirzadeh; Abbas Najafizadeh; Mohammad Moazeny

2009-01-01

199

Autosomal recessive forms of Charcot-Marie-Tooth disease.  

PubMed

In some countries with a high prevalence of consanguineous marriages, autosomal recessive inheritance is likely to account for the great majority of all forms of Charcot-Marie-Tooth (CMT) disease. As with the dominant forms, it is usual to differentiate the demyelinating forms (autosomal recessive -CMT1 or AR-CMT4) from the axonal forms (AR-CMT2). Genetic analysis of large families with recessive transmission has proved to be an efficient mean of discovering novel CMT genotypes (eg, the genes GDAP1, MTMR2, MTMR13, KIAA1985, NDGR1, periaxin, and lamin). Because of the clinical, electrophysiologic, and histologic heterogeneity of these patients, it is likely that there are numerous genes that remain to be discovered, which will probably make classification even more complex. Clinical, and especially histologic, phenotypes often lead to a suspicion that a specific gene is implicated. There is, therefore, an indication for nerve biopsy to orient diagnostic research in molecular biology, which is presently very time consuming and can only be performed in highly specialized laboratories. PMID:15324608

Vallat, J M; Grid, D; Magdelaine, C; Sturtz, F; Tazir, M

2004-09-01

200

Observations, light curves analysis and pulsation behavior of the Algol-type eclipsing binary system XX Cep  

NASA Astrophysics Data System (ADS)

We present the long term photometric variations of the classical Algol type binary XX Cep with a ? Scuti type pulsating component. Modeling of the system shows that the secondary component fills its Roche lobe. The derived physical and geometrical parameters of the system are M1=1.92M?, M2=0.36M?, R1=2.08R?, R2=2.39R?, L1=19.8L?, L2=2.1L?, a=9.8R? and the distance of the system as 312(18) pc. We obtained five new times of minima. Analysis of the mid-eclipse times indicate a period decrease of dP/dt=-1.9(2)×10-8 days/yr that can be interpreted in terms of a mass transfer rate (dM/dt=-1.2(3)×10-9M?/yr) from the secondary to primary component. The O-C diagram formed from all available timings, and thus the orbital period of the system, can be partly represented as a beat effect between two cyclical variations with different periods (P1 = 48(1) yr, P2 = 81(4) yr). We used PHOEBE program for light curves analysis and after modeling, the eclipse and proximity effects were removed from the light curves to analyze intrinsic variations caused by components of the system. Frequency analysis was done by Period04 and the residuals represent the pulsation of a more massive component of the system XX Cep with a period of 0.031 days, confirming the results of Lee et al. (2007).

Hosseinzadeh, B.; Pazhouhesh, R.; Yakut, K.

2014-02-01

201

A Statistical Comparison of the Blossom Blight Forecasts of MARYBLYT and Cougarblight with Receiver Operating Characteristic Curve Analysis.  

PubMed

ABSTRACT 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 analysis and 243 data sets. The rain threshold of Cougarblight was analyzed as a separate model termed Cougarblight and rain. Data were used as a whole and then grouped into geographic regions and cultivar susceptibilities. Frequency distributions of cases and controls, orchards or regions (depending on the data set), with and without observed disease, respectively, in all data sets overlapped. MARYBLYT, Cougarblight, and Cougarblight and rain all predicted blossom blight infection better than chance (P = 0.05). It was found that the blossom blight forecasters performed equivalently in the geographic regions of the east and west coasts of North America and moderately susceptible cultivars based on the 95% confidence intervals and pairwise contrasts of the area under the ROC curve. Significant differences (P < 0.05) between the forecasts of Cougarblight and MARYBLYT were found with pairwise contrasts in the England and very susceptible cultivar data sets. Youden's index was used to determine the optimal cutpoint of both forecasters. The greatest sensitivity and specificity for MARYBLYT coincided with the use of the highest risk threshold for predictions of infection; with Cougarblight, there was no clear single risk threshold across all data sets. PMID:18944181

Dewdney, M M; Biggs, A R; Turechek, W W

2007-09-01

202

Time-dependent nonlinear analysis of curved nonprismatic prestressed concrete box girder bridges  

Microsoft Academic Search

The accurate design and analysis of prestressed concrete (PC) bridges during their service life are very important issues. They affect public safety and economy. The behavior of prestressed bridges is complicated, i.e., it includes inelastic response, concrete cracking, steel yielding, creep, shrinkage, temperature, and tendon relaxation phenomena. This study considers the material nonlinearities (concrete, reinforcing mild steel, and prestressing tendon),

In-Ho Jang

1997-01-01

203

On the Application of Laplace Pairs to the Analysis of Relaxation Curves  

Microsoft Academic Search

The technique of using known Laplace pairs to find the distribution function of the relaxation coefficient or relaxation time in stress-strain analysis is described. A number of suitable transforms are given, and it is shown that one, involving the use of the square root of the time, leads to a particularly simple analytical method of attack on this problem.

H. H. Macey

1948-01-01

204

A Computer Program for Calculation of Calibration Curves for Quantitative X-Ray Diffraction Analysis.  

ERIC Educational Resources Information Center

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)

Blanchard, Frank N.

1980-01-01

205

How many loci on the X-chromosome of Drosophila melanogaster can mutate to recessive lethals  

SciTech Connect

The sensitivity of the sex-linked recessive lethal test is due to the fact that a very large number of loci are included in the mutation study. From extensive studies on the spontaneous sex-linked recessive lethal frequency and spontaneous specific locus mutation rates, it is possible to derive an estimate of the number of loci included in the recessive lethal test. The average number derived from three estimates on male and female germ cells in 563 loci. A second independent approach derives from published data which analyzed short regions of the genome and the proportion of loci within these regions which mutate to lethality. This analysis suggests that 830 loci are potentially lethal mutables. We describe the reasons for concluding that 600 to 800 loci of the approximately 1000 loci on the X-chromosome are involved in the X-linked recessive lethal test.

Abrahamson, S. (Univ. of Wisconsin, Madison); Wuergler, F.E.; DeJongh, C.; Meyer, H.U.

1980-01-01

206

The economic recession and its effect on utilization of elective total joint arthroplasty.  

PubMed

The United States economy entered a recession in December 2007. This study aims to determine whether the utilization of elective orthopedic surgeries has been impacted by this recession. From January 2007 to December 2009 at a single private practice in New Jersey, 4820 total joint replacement procedures were scheduled, of which 649 of those were cancelled. The rate of cancellation for financial reasons was compared to multiple economic measures by linear regression analysis. The results show that the rate of financially motivated cancellations increased over time concurring with multiple financial markers reflecting the economic recession. The results suggest that the recession has created a financial barrier for a significant number of Americans, leading to decreased utilization of care. While there was a statistically significant increase in cancellations for financial reasons, the overall rate of cancellations in the total joint population is still low, representing only about 1% of all cases. PMID:24340319

Klein, Gregg R; Parcells, Bertrand W; Levine, Harlan B; Dabaghian, Laurie; Hartzband, Mark A

2013-11-01

207

Leptin receptor (LEPR) SNP polymorphisms in HELLP syndrome patients determined by quantitative real-time PCR and melting curve analysis  

PubMed Central

Background Several studies have shown overexpression of leptin in microarray experiments in pre-eclampsia (PE) and in hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome. We decided to study four leptin receptor (LEPR) SNP polymorphisms in HELLP syndrome patients by using quantitative real-time PCR and melting curve analysis. Methods DNA was isolated from blood samples from 83 normotensive pregnant women and 75 HELLP syndrome patients. Four SNPs, LEPR c.326A>G (K109), LEPR c.668A>G (Q223R), LEPR c.1968G>C (K656N) and LEPR c.3024A>G (S1008) were determined by quantitative real-time PCR and melting curve analysis. Investigators were blinded to clinical outcomes. Results LEPR c.326A>G, LEPR c.668A>G, LEPR c.1968G>C and LEPR c.3024A>G allele, genotype and haplotype polymorphisms were not different in HELLP syndrome patients and normotensive healthy pregnants. There were strong linkage disequilibrium (LD) between loci c.326A>G and c.6687A>G (D' = 0.974), and c.668A>G and c.1968G>C (D' = 0.934), and c.326A>G and c.1968G>C (D' = 0.885), and c.1968G>C and c.3024A>G (D' = 1.0). However, linkages of c.3024A>G with c.668A>G (D' = 0.111) and c.326A>G (D' = 0.398) were weak. The Hardy-Weinberg equilibrium was observed for all polymorphisms. However the LEPR c.326A>G AG genotype was twice more frequent and the (AG AG GG AG) haplotype was three times more frequent in HELLP syndrome patients. The introduced quantitative real-time PCR combined with melting curve analysis is a fast and reliable method for the determination of LEPR SNPs. Conclusion Although certain LEPR haplotypes are more frequent in HELLP syndrome, we conclude that there is no compelling evidence that the four studied LEPR SNP polymorphisms associated with the development of HELLP syndrome. PMID:20149225

2010-01-01

208

Glacier recession in Iceland and Austria  

NASA Technical Reports Server (NTRS)

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.

Hall, Dorothy K.; Williams, Richard S., Jr.; Bayr, Klaus J.

1992-01-01

209

Bradford Curves.  

ERIC Educational Resources Information Center

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)

Rousseau, Ronald

1994-01-01

210

Curved Knives  

Microsoft Academic Search

IT may interest your correspondent, Dr. Otis T. Mason, to know that the curved ``drawing-knife'' described by him has representatives in Western (British) India. The Kolis (fishing races) of the Bombay coast wore lately, and some still wear, knives made by local blacksmiths, of which the blade, 2 to 3 inches long, was shaped and edged like that of an

W. F. Sinclair

1897-01-01

211

New light curves and analysis of the short-period Algol XZ Canis Minoris  

NASA Astrophysics Data System (ADS)

We present new observations of the short-period Algol XZ Canis Minoris made between 25 Dec. 1992 and 1 Mar. 1993. Two new epochs of minimum light were determined and an improved ephemeris is given. Analysis of the observations with the latest version of the Wilson-Devinney program shows that the system is semidetached. Our solution does not indicate the presence of third light, whereas some previously published solutions required large amounts of third light.

Terrell, Dirk; Gunn, J. B.; Kaiser, Daniel H.

1994-02-01

212

InTube DNA Methylation Profiling by Fluorescence Melting Curve Analysis  

Microsoft Academic Search

Background: Most PCR assays for detection of 5-meth- ylcytosine in genomic DNA entail a two-step procedure, comprising initial PCR amplification and subsequent product analysis in separate operations that usually require manual transfer. These methods generally pro- vide information about methylation of only a few CpG dinucleotides within the target sequence. Methods: An in-tube methylation assay is described that integrates amplification

Jesper Worm; Anni Aggerholm; Per Guldberg

2001-01-01

213

A Latent Growth Curve Analysis of Early and Increasing Peer Victimization as Predictors of Mental Health Across Elementary School  

PubMed Central

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

Rudolph, Karen D.; Troop-Gordon, Wendy; Hessel, Elenda T.; Schmidt, Jennifer D.

2011-01-01

214

First-order-reversal-curve analysis of exchange-coupled SmCo/NdFeB nanocomposite alloys  

NASA Astrophysics Data System (ADS)

Exchange-coupled SmCo5/Nd2Fe14B nanocomposite magnets have been fabricated by ball milling of the micrometer sized SmCo5 and Nd2Fe14B powders. The influence of Nd2Fe14B content on the microstructure and magnetic properties of these hybrid alloys was investigated. The alloys that show strong intergrain exchange-coupling behavior with (BH)max=2.95 MGOe was obtained when the two hard phases are well coupled. A first-order-reversal-curve (FORC) analysis was performed for both SmCo5 single-phase magnet and SmCo5/Nd2Fe14B hybrid magnet; the FORC diagrams results show two major peaks for the hybrid magnets. In both cases, the magnetization reversal behaviors for these alloys were discussed in detail and are consistent with the results of ?M plots.

Pan, Mingxiang; Zhang, Pengyue; Ge, Hongliang; Yu, Nengjun; Wu, Qiong

2014-06-01

215

Statistical methods for pavement performance curve building, historical analysis, data sampling and storage. Final report, May 1997--July 1998  

SciTech Connect

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.

Zimmerman, K.A.; Bahulkar, A.M.

1998-08-01

216

Analysis of stellar occultation data - Effects of photon noise and initial conditions. [planetary atmosphere temperature, pressure and density profiles from occultation light curve  

NASA Technical Reports Server (NTRS)

An occultation light curve can be analyzed to provide information about a planetary atmosphere. Temperature, pressure, and number density profiles for the atmosphere of Mars are derived from a series of boundary layer equations, which invert equal increments of altitude (as opposed to time) in order to predict the noise quality of the occultation. Numerical results are given for a noisy isothermal light curve, with special attention to error analysis.

French, R. G.; Elliot, J. L.; Gierasch, P. J.

1978-01-01

217

Discriminant Analysis of Xenon-133 Washout Curves, An Index of Lower Extremity Vascular Impairment  

PubMed Central

To evaluate the degree of vascular impairment in muscles of the lower extremity, xenon-133 washout was studied in a group of legs with impaired circulation and in another group with normal circulation during both resting and stressed conditions. Blood flow was computed as a discrete time function based on a single compartment model with time-varying flow. Linear discriminant analysis was performed, using the flows at the discrete times as discriminators. The resulting discriminant coefficients allow any leg so studied to be represented as a point on the discriminant score axis, which thus becomes the axis of severity of impairment.

Wilson, P. David; Fallon, F. Graham; Buddemeyer, Edward U.

1977-01-01

218

BAYESIAN WAVELET-BASED CURVE CLASSIFICATION VIA DISCRIMINANT ANALYSIS WITH MARKOV RANDOM TREE PRIORS  

PubMed Central

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

Stingo, Francesco C.; Vannucci, Marina; Downey, Gerard

2014-01-01

219

Blast response of curved carbon/epoxy composite panels: Experimental study and finite-element analysis  

NASA Astrophysics Data System (ADS)

Experimental and numerical studies were conducted to understand the effect of plate curvature on blast response of carbon/epoxy composite panels. A shock-tube system was utilized to impart controlled shock loading to quasi-isotropic composite panels with differing range of radii of curvatures. A 3D Digital Image Correlation (DIC) technique coupled with high-speed photography was used to obtain out-of-plane deflection and velocity, as well as in-plane strain on the back face of the panels. Macroscopic post-mortem analysis was performed to compare yielding and deformation in these panels. A dynamic computational simulation that integrates fluid-structure interaction was conducted to evaluate the panel response in general purpose finite-element software ABAQUS/Explicit. The obtained numerical results were compared to the experimental data and showed a good correlation.

Phadnis, V. A.; Kumar, P.; Shukla, A.; Roy, A.; Silberschmidt, V. V.

2013-07-01

220

Recession of Martian north polar cap - 1977-1978 Viking observations  

NASA Technical Reports Server (NTRS)

The regression curve for the 1977-1978 sublimation of the north polar cap of Mars is extracted from Viking orbiter imaging data. The recession observed during the spring season is quite consistent with previous observations and is in excellent agreement with telescopic data obtained concurrently. A receding late winter boundary is identified, but owing to hood obscuration this boundary cannot be definitely attributed to a surface cap.

James, P. B.

1979-01-01

221

The Recession of the Niagara Gorge  

Microsoft Academic Search

BEFORE the survey of 1842, the only data for estimating the rate of recession of the Niagara Gorge were the observations of the people of the neighbourhood. Mr. Bakewell, in 1829, ``was informed by Mr. Forsyth, the proprietor of the Pavilion Hotel on the Canada side, that during his residence of forty years the Falls had receded forty yards'' (American

Edward G. Bourne

1891-01-01

222

Brachydactylia with symphalangism, probably autosomal recessive  

Microsoft Academic Search

Association, in one patient, of the following malformations: brachydactylia of all segments but terminal phalanges; proximal symphalangism of many fingers and toes; abnormalities of carpal and tarsal bones; partial duplication of both big toes; mild hypertelorism. Genetic transmission seems to be recessive autosomal.

Roland Walbaum; Claude Hazard; Roger Cordier

1976-01-01

223

Drilldown on Poverty and the Recession  

E-print Network

Drilldown on Poverty and the Recession Working Paper Prepared by Lois M. Quinn Employment analyzes recently released 1-year estimates of poverty and economic conditions data from the U.S. Census bases to help residents and public officials address concerns related to poverty, employment

Saldin, Dilano

224

Weathering the Recession in College Health  

ERIC Educational Resources Information Center

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…

Christmas, William A.

2010-01-01

225

Job Creation Policies and the Great Recession  

E-print Network

The adverse labor market effects of the Great Recession have intensified interest in policy efforts to spur job creation. The two most direct job creation policies are subsidies that go to workers and hiring credits that go to employers. Evidence indicates that worker subsidies are generally more effective at creating jobs. However, the unique circumstances of recovery from the Great Recession, especially the weak demand for labor, make hiring credits more effective in the short term. The slow recovery of employment in the aftermath of the Great Recession has sharpened debate over policies to spur job creation. Policies for directly creating jobs include hiring credits, which are subsidies for employers to hire workers, and worker subsidies, which subsidize individuals to enter the labor market. Hiring credits effectively subsidize wages when employers hire. They increase demand for labor by lowering the cost of labor to employers. Worker subsidies raise worker earnings, thereby encouraging people to work. Although economic theory predicts that both policies should lead to higher employment, evidence suggests that worker subsidies are more effective. However, drawing on Neumark (2011), this Economic Letter argues that unique circumstances of the recovery from the Great Recession—including weak labor

David Neumark

2012-01-01

226

Nevada, the Great Recession, and Education  

ERIC Educational Resources Information Center

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…

Verstegen, Deborah A.

2013-01-01

227

The effect of recessions on gambling expenditures.  

PubMed

This article examines the influence of the business cycle on expenditures of three major types of legalized gambling activities: Casino gambling, lottery, and pari-mutuel wagering. Empirical results are obtained using monthly aggregated US per capita consumption time series for the period 1959.01-2010.08. Among the three gambling activities only lottery consumption appears to be recession-proof. This series is characterized by a vast and solid growth that exceeds the growth in income and the growth in other gambling sectors. Casino gambling expenditures show a positive growth during expansions and no growth during recessions. Hence, the loss in income during recessions affects casino gambling. However, income shocks which are not directly related to the business cycle do not influence casino gambling expenditures. Pari-mutuel wagering displays an overall negative trend and its average growth rate is smaller than the growth in income, especially during recessions. The findings of this article provide important implications for the gambling industry and for local governments. PMID:22143980

Horváth, Csilla; Paap, Richard

2012-12-01

228

Floridian Coastline Recession February 18, 2008  

E-print Network

to Florida over the next 50 years, predictions suggest sea level increase anywhere between 0 cm and 20 cm [3Floridian Coastline Recession February 18, 2008 Abstract Rising sea levels are of significant concern as global temperatures con- tinue to mount. Predicted increases in sea level place coastal regions

Morrow, James A.

229

The Recession and Education: Seize New Opportunities!  

ERIC Educational Resources Information Center

The teaching profession has long been thought of as recession proof. Indeed, that may have been one of the reasons why teachers took far lower starting salaries right out of college. Perhaps the greatest common feature of teachers, besides their desire to serve society in a humanitarian way, may be the lack of risk-taking the occupation previously…

Haskvitz, Alan

2011-01-01

230

The Great Recession and the Great Depression  

Microsoft Academic Search

This paper discusses parallels between our current recession and the Great Depression for the intelligent general public. It stresses the role of economic models and ideas in public policy and argues that gold-standard mentality still holds sway today. The parallels are greatest in the generation of the crises, and they also illuminate the policy choices being made today. We have

Peter Temin

2010-01-01

231

What Colleges Can Learn from Recessions Past  

ERIC Educational Resources Information Center

The present financial and credit crisis is unprecedented in recent history, resembling in many ways the onset of the Depression of the 1930s more than subsequent recessions. Presumably, one has learned something about managing such events and will not permit the current economic mess to deteriorate to Depression levels. In this article, the author…

Breneman, David W.

2008-01-01

232

Development of Curved-Plate Elements for the Exact Buckling Analysis of Composite Plate Assemblies Including Transverse-Shear Effects  

NASA Technical Reports Server (NTRS)

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.

McGowan, David M.

1999-01-01

233

A recessive genetic model and runs of homozygosity in major depressive disorder  

PubMed Central

Genome-wide association studies (GWASs) of major depressive disorder (MDD) have yet to identify variants that surpass the threshold for genome-wide significance. A recent study reported that runs of homozygosity (ROH) are associated with schizophrenia, reflecting a novel genetic risk factor resulting from increased parental relatedness and recessive genetic effects. Here we undertake an analysis of ROH for MDD using the 9,238 MDD cases and 9,521 controls reported in a recent mega-analysis of 9 GWAS. Since evidence for association with ROH could reflect a recessive mode of action at loci, we also conducted a genome-wide association analyses under a recessive model. The genome-wide association analysis using a recessive model found no significant associations. Our analysis of ROH suggested that there was significant heterogeneity of effect across studies in effect (p=0.001), and it was associated with genotyping platform and country of origin. The results of the ROH analysis show that differences across studies can lead to conflicting systematic genome-wide differences between cases and controls that are unaccounted for by traditional covariates. They highlight the sensitivity of the ROH method to spurious associations, and the need to carefully control for potential confounds in such analyses. We found no strong evidence for a recessive model underlying MDD. PMID:24482242

Power, Robert A.; Keller, Matthew C.; Ripke, Stephan; Abdellaoui, Abdel; Wray, Naomi R.; Sullivan, Patrick F; Breen, Gerome

2014-01-01

234

Cone-beam computed tomography analysis of curved root canals after mechanical preparation with three nickel-titanium rotary instruments  

PubMed Central

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

Elsherief, Samia M.; Zayet, Mohamed K.; Hamouda, Ibrahim M.

2013-01-01

235

Genetics Home Reference: Autosomal recessive cerebellar ataxia type 1  

MedlinePLUS

... disorder catalog Conditions > Autosomal recessive cerebellar ataxia type 1 (often shortened to ARCA1 ) On this page: Description ... What is ARCA1? Autosomal recessive cerebellar ataxia type 1 (ARCA1) is a condition characterized by progressive problems ...

236

CASE REPORT Open Access Autosomal recessive cerebellar ataxia caused  

E-print Network

CASE REPORT Open Access Autosomal recessive cerebellar ataxia caused by mutations in the PEX2 gene Objective: To expand the spectrum of genetic causes of autosomal recessive cerebellar ataxia (ARCA). Case is warranted in children and adults with ARCA. Background Main causes of autosomal recessive cerebellar ataxia

Paris-Sud XI, Université de

237

Understanding High Recession Rates of Carbon Ablators Seen in Shear Tests in an Arc Jet  

NASA Technical Reports Server (NTRS)

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.

Driver, David M.; Olson, Michael W.; Barnhardt, Michael D.; MacLean, Matthew

2010-01-01

238

Analysis of experimental binding curves of EtBr with single- and double-stranded DNA at small fillings  

NASA Astrophysics Data System (ADS)

In this paper, a method that allows to analyze the binding curves of ligand (EtBr) with single-stranded (ss) and double-stranded (ds) DNA, when there are at least two modes of ligand binding to DNA at small fillings has been proposed. The obtained experimental binding curves for EtBr-ssDNA and EtBr-dsDNA have two clearly expressed linear regions. These curves were analyzed by two modes: Experimental points on linear regions were described by two different lines and all experimental points were described by single curve. It was revealed that the description by single curve permits obtaining more precise data of binding parameters (i.e. binding constant and number of base pairs that bind one ligand molecule). Moreover, the proposed method permits determining the value of proportion of binding sites of each binding mode.

Vardevanyan, Poghos O.; Arakelyan, Valeri B.; Parsadanyan, Marine A.; Antonyan, Ara P.; Hovhannisyan, Gohar G.; Shahinyan, Mariam A.

2014-08-01

239

Autosomal recessive cutis laxa syndrome revisited  

PubMed Central

The clinical spectrum of the autosomal recessive cutis laxa syndromes is highly heterogeneous with respect to organ involvement and severity. One of the major diagnostic criteria is to detect abnormal elastin fibers. In several other clinically similar autosomal recessive syndromes, however, the classic histological anomalies are absent, and the definite diagnosis remains uncertain. In cutis laxa patients mutations have been demonstrated in elastin or fibulin genes, but in the majority of patients the underlying genetic etiology remains unknown. Recently, we found mutations in the ATP6V0A2 gene in families with autosomal recessive cutis laxa. This genetic defect is associated with abnormal glycosylation leading to a distinct combined disorder of the biosynthesis of N- and O-linked glycans. Interestingly, similar mutations have been found in patients with wrinkly skin syndrome, without the presence of severe skin symptoms of elastin deficiency. These findings suggest that the cutis laxa and wrinkly skin syndromes are phenotypic variants of the same disorder. Interestingly many phenotypically similar patients carry no mutations in the ATP6V0A2 gene. The variable presence of protein glycosylation abnormalities in the diverse clinical forms of the wrinkled skin-cutis laxa syndrome spectrum necessitates revisiting the diagnostic criteria to be able to offer adequate prognosis assessment and counseling. This paper aims at describing the spectrum of clinical features of the various forms of autosomal recessive cutis laxa syndromes. Based on the recently unraveled novel genetic entity we also review the genetic aspects in cutis laxa syndromes including genotype–phenotype correlations and suggest a practical diagnostic approach. PMID:19401719

Morava, Eva; Guillard, Mailys; Lefeber, Dirk J; Wevers, Ron A

2009-01-01

240

Recovering From Recession - With Far Less Pain  

NSDL National Science Digital Library

Thirty-seventh monthly installment of our "What A Year!" website project, introducing life science breakthroughs to middle and high school students and their teachers. Gum recession is both aesthetically unpleasant and medically risky. At risk are the patient's teeth and oral health. But the traditional treatment has been painful and not completely satisfactory. Now there is a new treatment that works better and reduces pain and discomfort.

2010-05-04

241

Photogrammetric recession measurements of an ablating surface  

NASA Technical Reports Server (NTRS)

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.

Schairer, Edward T. (Inventor); Heineck, James T. (Inventor)

2012-01-01

242

Embrasure morphology and central papilla recession  

PubMed Central

Background: The aim of this study was to ascertain the effects of vertical and horizontal distances between the maxillary central incisors on the presence of interproximal dental papilla and to assess the association between the embrasure morphology and central papilla recession. Materials and Methods: The central papilla was visually assessed in 50 subjects using the standardized periapical radiographs of maxillary central incisors. The following vertical distances were measured; distance from the contact point to papilla tip, CP to proximal cementoenamel (pCEJ) junction, bone crest to CP (BC-CP) and BC-PT. The horizontal distance measured was interdental width (IDW) at pCEJ level. The measurements were recorded using a digital electronic caliper. Results: Significant association between the embrasure morphology and central papilla recession was observed for all study groups. All the interdental variables were significantly related to the presence of interdental papillae, with BC-CP distance being the strongest determinant of central papilla presence. The percentage of interdental papilla presence was 100% when the BC-CP distance was ?6 mm and IDW ranged between 0.5 and 1.5 mm. Central papilla recession was observed most frequently with wide-long and narrow-long embrasure morphology. Conclusion: In relation to maxillary central incisors, all the interdental variables have significant influences on the presence of interdental papillae, with distance from BC to CP being the strongest determinant of central papilla presence. PMID:24872628

Saxena, Divya; Kapoor, Anoop; Malhotra, Ranjan; Grover, Vishakha

2014-01-01

243

Latent Growth Curve Analysis of Fear during a Speech Task before and after Treatment for Social Phobia  

PubMed Central

Models of social phobia highlight the importance of anticipatory anxiety in the experience of fear during a social situation. Anticipatory anxiety has been shown to be highly correlated with performance anxiety for a variety of social situations. A few studies show that average ratings of anxiety during the anticipation and performance phases of a social situation decline following treatment. Evidence also suggests that the point of confrontation with the feared stimulus is the peak level of fear. No study to date has evaluated the pattern of anxious responding across the anticipation, confrontation, and performance phases before and after treatment, which is the focus of the current study. Socially phobic individuals (N=51) completed a behavioral avoidance task before and after two types of manualized cognitive behavioral therapy, and gave ratings of fear during the anticipation and performance phases. Results from latent growth curve analysis were the same for the two treatments and suggest that before treatment, anxiety sharply increased during the anticipation phase, was highly elevated at the confrontation, and, to a gradually increased during the performance phase. After treatment, anxiety increased during the anticipation phase, although at a much slower rate than at pretreatment, peaking at confrontation, and declined at the performance phase. The findings suggest that anticipatory experiences are critical to the experience of fear for public speaking and should be incorporated into exposures. PMID:21907972

Price, Matthew; Anderson, Page L.

2011-01-01

244

Analysis of the terrestrial ion foreshock: 2D Full-Particle simulation of a curved supercritical shock  

NASA Astrophysics Data System (ADS)

Two distinct ion populations backstreaming into the solar wind have been clearly evidenced by various space missions within the quasi-perpendicular region of the ion foreshock located upstream of the Earth's Bow shock (i.e. for 45° ? Theta_Bn ? 90°, where Theta_Bn is the angle between the shock normal and the upstream magnetostatic field): (i) field-aligned ion beams (« FAB ») characterized by a gyrotropic distribution, and (ii) gyro-phase bunched ions («GPB »), characterized by a NON gyrotropic distribution. The origin of these backstreaming ions has not been clearly identified and is presently analyzed with the help of 2D PIC simulation of a curved shock, where full curvature effects, time of flight effects and both electrons and ions dynamics are fully described within a self consistent approach. Present simulations evidence that these two populations can be effectively created directly by the shock front without invoking microinstabilities. The analysis of both individual and statistical ion trajectories evidences that: (i) two new parameters, namely the interaction time DT_inter and distance of penetration L_depth into the shock wave, play a key role and allow to discriminate these two populations. "GPB" population is characterized by a very short interaction time (DT_inter = 1 to 2 Tci) in comparison to the "FAB" population (DT_inter = 2 Tci to 10 Tci) which moves back and forth between the upstream edge of the shock front and the overshoot, where tci is the upstream ion gyroperiod. (ii) the importance of the injection angle (i.e. the angle between the normal of the shock front and the gyration velocity when ions reach the shock) to understand how the reflection process takes place. (iii) "FAB" population drifts along the curved shock front scanning a large Theta_Bn range from 90°. (iv) "GPB" population is embedded within the "FAB" population near the shock front which explains the difficulty to identify such a population in the experimental data. The use of two additional parameters DT_inter and L_depth is necessary to separate clearly both populations.

Lembege, B.; Savoini, P.; Stienlet, J.

2013-05-01

245

Atlas of fatigue curves  

Microsoft Academic Search

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

1986-01-01

246

Principal curve time warping  

Microsoft Academic Search

Time warping finds use in many fields of time series analysis, and it has been effectively implemented in many different application areas. Rather than focusing on a particular application area we approach the general problem definition, and employ principal curves, a powerful machine learning tool, to improve the noise robustness of existing time warping methods. The increasing noise level is

Umut Ozertem; Deniz Erdogmus

2009-01-01

247

A homogeneous analysis of transit light curves of CoRoT-Sz. Csizmadia (1), Th. Pasternacki (1), P. Bord (2) and the CEST Team  

E-print Network

A homogeneous analysis of transit light curves of CoRoT- exoplanets Sz. Csizmadia (1), Th Paris-Sud 11 & CNRS (UMR 8617), Bât. 121, 91405 Orsay, France Abstract CoRoT discovered more than 17. Introduction CoRoT (Convection, Rotation and planetary Transit) is a 27 cm diameter space-telescope [1

Bordé, Pascal J.

248

Effects of Tip Clearance and Casing Recess on Heat Transfer and Stage Efficiency in Axial Turbines  

NASA Technical Reports Server (NTRS)

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.

Ameri, A. A.; Steinthorsson, E.; Rigby, David L.

1998-01-01

249

Langevin Equation on Fractal Curves  

E-print Network

We analyse a random motion of a particle on a fractal curve, using Langevin approach. This involves defining a new velocity in terms of mass of the fractal curve, as defined in recent work. The geometry of the fractal curve, hence plays an important role in this analysis. A Langevin equation with a particular noise model is thus proposed and solved using techniques of the newly developed $F^\\alpha$-Calculus .

Seema Satin; A. D. Gangal

2014-04-28

250

High-throughput avian molecular sexing by SYBR green-based real-time PCR combined with melting curve analysis  

PubMed Central

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

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

251

Development of Web-based Load Duration Curve system for analysis of total maximum daily load and water quality characteristics in a waterbody.  

PubMed

In many states of the US, the total maximum daily load program has been widely developed for watershed water quality restoration and management. However, the total maximum daily load is often represented as an average daily pollutant load based on average long-term flow conditions, and as such, it does not adequately describe the problems they aim to address. Without an adequate characterization of water quality problems, appropriate solutions cannot be identified and implemented. The total maximum daily load approach should consider adequate water quality characterizations based on overall flow conditions rather than on a single flow event such as average daily flow. The Load Duration Curve, which provides opportunities for enhanced pollutant source and best management practice targeting both in the total maximum daily load development and in water quality restoration efforts, has been used for the determination of appropriate total maximum daily load targets. However, at least 30 min to an hour is needed for unskilled people based on our experiences to generate the Load Duration Curve using a desktop-based spreadsheet computer program. Therefore, in this study, the Web-based Load Duration Curve system (https://engineering.purdue.edu/?ldc/) was developed and applied to a study watershed for an analysis of the total maximum daily load and water quality characteristics in the watershed. This system provides diverse options for Flow Duration Curve and Load Duration Curve analysis of a watershed of interest in a brief time. The Web-based Load Duration Curve system is useful for characterizing the problem according to flow regimes, and for providing a visual representation that enables an easy understanding of the problem and the total maximum daily load targets. In addition, this system will be able to help researchers identify appropriate best management practices within watersheds. PMID:22325582

Kim, Jonggun; Engel, Bernard A; Park, Youn Shik; Theller, Larry; Chaubey, Indrajeet; Kong, Dong Soo; Lim, Kyoung Jae

2012-04-30

252

Analysis of the low part of stress-strain curves in rat skin. Influence of age and desmotropic drugs.  

PubMed

Stress-strain behaviour of skin strips in rats at different ages or after treatment with prednisolone or D-penicillamine has been analyzed. Special attention has been paid to the lower part of the stress-strain curves. A "hump" at an extension degree of 30% of original length was noted. When rats of different ages were compared this phenomenon was observed predominantly at an age of 2 months. Futhermore, this hump was remarkable in rats treated with prednisolone. When the stress-strain curves of rats at different ages or after treatment were averaged and normalized, the most pronounced deviations were found at an age of 2 months or after prednisolone treatment. The maximum of deviation from Hooke's law occurred at a relative extension degree of 70%. Thus, the maturation process and the influence of corticosteroid affected mostly the second part of the stress-strain curve. In order to evaluate further the stress-strain curves 3 consecutive tangents of the stress-strain curves indicating modules of elasticity were evaluated. The first and second modules of elasticity showed a minimum at an age of 2 months, whereas the ultimate elasticity modules increased with maturation up to a maximum at 12 months followed by a decrease similar to that observed in tensile strength at an age of 24 months. PMID:869577

Vogel, H G; Hilgner, W

1977-04-27

253

Mandibulofacial dysostosis, microcephaly and thorax deformities in two brothers: a new recessive syndrome?  

PubMed

We report two brothers who presented with mandibulofacial dysostosis, growth retardation, microcephaly, thoracic deformities and conductive hearing loss along with asplenia in one case and aplasia of the gallbladder in the other. The pattern of malformations differs significantly from established syndromes with mandibulofacial dysostosis such as Nager syndrome or Genée-Wiedemann syndrome and also from cerebro-costo-mandibular syndrome. As chromosome analysis revealed normal male karyotypes, we consider this to be a distinct heritable syndrome that may be either autosomal recessive or X-chromosomal recessive. PMID:11310989

Delb, W; Lipfert, S; Henn, W

2001-04-01

254

Multilayer theory for delamination analysis of a composite curved bar subjected to end forces and end moments  

NASA Technical Reports Server (NTRS)

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.

Ko, William L.; Jackson, Raymond H.

1989-01-01

255

The eclipsing binary star V380 Gem: First V and Rc light curve analysis and estimation of its absolute elements  

NASA Astrophysics Data System (ADS)

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.

Barani, C.; Martignoni, M.; Acerbi, F.

2013-10-01

256

Late infantile autosomal recessive myotonia, mental retardation, and skeletal abnormalities: a new autosomal recessive syndrome.  

PubMed Central

Four sibs of non-consanguineous parents who had myotonia from late infancy are described. Mild to moderate mental retardation, severe bone abnormalities of the vertebral column (mainly in the thoracolumbar region), and short stature were also observed. Autosomal recessive inheritance is demonstrated. These cases are compared with reported cases of the Schwartz-Jampel syndrome. Images PMID:6716408

Richieri-Costa, A; Garcia da Silva, S M; Frota-Pessoa, O

1984-01-01

257

Recess and the Importance of Play. A Position Statement on Young Children and Recess.  

ERIC Educational Resources Information Center

In this position statement, the National Association of Early Childhood Specialists in State Departments of Education asserts that recess is an essential component of education and that preschool and elementary school children must have the opportunity to participate in regular periods of active, free play with peers. The statement summarizes…

National Association of Early Childhood Specialists in State Departments of Education.

258

Curves and Their Properties.  

ERIC Educational Resources Information Center

This volume, a reprinting of a classic first published in 1952, presents detailed discussions of 26 curves or families of curves, and 17 analytic systems of curves. For each curve the author provides a historical note, a sketch or sketches, a description of the curve, a discussion of pertinent facts, and a bibliography. Depending upon the curve,…

Yates, Robert C.

259

Is the Elimination of Recess in School a Violation of a Child's Basic Human Rights?  

ERIC Educational Resources Information Center

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…

Dubroc, Alicia M.

2007-01-01

260

Study of acoustic transducer protrusion and recess effects on ultrasonic flowmeter measurement by numerical simulation  

Microsoft Academic Search

In order to improve the measurement performance of dry calibration on ultrasonic flowmeter, the Computational Fluid Dynamic (CFD) modeling approach of the effect on transducer protrusion and recess are mainly discussed in the paper while its effects on ultrasonic flowmeter accuracy are also presented. Through comparing simulation results to experimental data, the CFD modeling is firstly determined. Then, detail analysis

Dandan Zheng; Pengyong Zhang; Tianshi Xu

2011-01-01

261

The Process of Integration of Newcomers at School: Students and Gender Networking during School Recess  

ERIC Educational Resources Information Center

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,…

Rodriguez-Navarro, Henar; García-Monge, Alfonso; Rubio-Campos, Maria del Carmen

2014-01-01

262

Autosomal recessive nonsyndromic deafness genes: a review  

PubMed Central

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

Duman, Duygu; Tekin, Mustafa

2013-01-01

263

Hubble's law and Superluminity Recession Velocities  

E-print Network

The extension of the so-called "empty" (with gravity and antigravity that compensate each other in full or do not exist at all) universe and cosmological redshift in it are considered in this paper. Its flat space-time can be submitted not only as manifold with Friedman-Robertson-Walker metrics (FRW) of the general theory of relativity (GR) but also as space-time with usual Minkowski metrics (M-metrics) of the special theory of relativity (SR); the transfer of metrics can be done by suitable transformation of reference frame. Both below-mentioned statements are equally fair for such the universe. First: the distant galaxies can have superluminity recession velocities in FRW-space of GR; we have no right to use here the formula of relativistic Doppler effect. Secondly: the SR theory is fair in the M-space and, accordingly, recession velocities of the same galaxies here can aspire to the speed of light only. In this article it is shown that, despite opposite pictures in FRW-and M- spaces, in the careful account of all details both approaches yield results agreed among them. Thus, actually there are no contradictions between the interpretations of cosmological redshift, based on SR and GR.

Leonid S. Sitnikov

2006-02-05

264

Autosomal recessive inherited phosphofructokinase deficiency in English springer spaniel dogs.  

PubMed

Three families of English springer spaniel dogs with phosphofructokinase (PFK) deficiency causing haemolysis were studied. Four male dogs and one female dog with chronic haemolysis and haemolytic crises were found to have markedly reduced PFK activity in erythrocytes (8-20% of control English springer spaniels). PFK-deficient erythrocytes exhibited an extreme alkaline and sucrose lysis. The oxygen dissociation curve of erythrocyte suspensions was shifted to the left with a 50% saturation of haemoglobin at a partial oxygen pressure of 16-17 mmHg (normal 26-31 mmHg). Muscle wasting and mildly increased serum creatine phosphokinase activity were also noted. Six clinically normal first degree relatives of affected dogs had erythrocyte PFK activities that were 38-51% of controls. In these family members, there was an erythrocytosis and mild reticulocytosis probably due to a mildly enhanced haemoglobin-oxygen affinity but no increase in serum creatine phosphokinase. These studies confirm the familial nature of muscle-type PFK deficiency in English springer spaniels and support the conclusion that this animal model of the human glycogen storage disease type VII is inherited as an autosomal recessive trait. PMID:2940948

Giger, U; Reilly, M P; Asakura, T; Baldwin, C J; Harvey, J W

1986-01-01

265

ECS 178 Course Notes B EZIER CURVES ARE B-SPLINE CURVES  

E-print Network

ECS 178 Course Notes B ´EZIER CURVES ARE B-SPLINE CURVES Kenneth I. Joy Institute for Data Analysis, this is obvious. Since B-Spline curves are piecewise B´ezier curves, it follows directly that a single B´ezier curve must be a B-Spline. You are right! But it is also informative to "find" a B´ezier curve

California at Davis, University of

266

Statistical methods for pavement performance curve building, historical analysis, data sampling and storage: Appendix D. Final report  

SciTech Connect

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.

NONE

1998-08-01

267

Differential School Effects among Low, Middle, and High Social Class Composition Schools: A Multiple Group, Multilevel Latent Growth Curve Analysis  

ERIC Educational Resources Information Center

This study uses large-scale survey data and a multiple group, multilevel latent growth curve model to examine differential school effects between low, middle, and high social class composition public schools. The results show that the effects of school inputs and school practices on learning differ across the 3 subpopulations. Moreover, student…

Palardy, Gregory J.

2008-01-01

268

A Unified Latent Curve, Latent State-Trait Analysis of the Developmental Trajectories and Correlates of Positive Orientation  

Microsoft Academic Search

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 State-Trait Model (Tisak & Tisak, 2000), results corroborated (a)

Guido Alessandri; Gian Vittorio Caprara; John Tisak

2012-01-01

269

A Unified Latent Curve, Latent State-Trait Analysis of the Developmental Trajectories and Correlates of Positive Orientation  

ERIC Educational Resources Information Center

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…

Alessandri, Guido; Caprara, Gian Vittorio; Tisak, John

2012-01-01

270

A rare case of respiratory disorders associated with two autosomal recessive diseases and male infertility  

PubMed Central

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

Costa, Sergio López; Scigliano, Sergio; Menga, Guillermo; Demiceu, Sergio; Palaoro, Luis Alberto

2013-01-01

271

Quotient curves of the GK curve  

E-print Network

For every $q=l^3$ with $l$ a prime power greater than 2, the GK curve $X$ is an $F_{q^2}$-maximal curve that is not $F_{q^2}$-covered by any $F_{q^2}$-maximal Deligne-Lusztig curve. Interestingly, $X$ has a very large $F_{q^2}$-automorphism group with respect to its genus. In this paper we compute the genera of a large variety of curves that are Galois-covered by the GK curve, thus providing several new values in the spectrum of genera of $F_{q^2}$-maximal curves.

Giulietti, Stefania Fanali; Massimo

2009-01-01

272

Towards the Development of a Semiautomatic Pipeline for Investigating the Viscosity Parameter of Disks of Be Stars by the Analysis of Light Curves  

NASA Astrophysics Data System (ADS)

In ``Viscous Decretion Disk'' (VDD) model for circumstellar disks Be stars, material is dynamically ejected near the equator of the star and diffuses outwards by means of viscous forces. Following the ? -disk approach for the VDD, we show that dynamical disk models coupled with the radiative transfer code HDUST can be used for constraining fundamental disk parameters, such as the ? viscosity parameter, the base density, the orientation angle i of the disk and the mass injection rate, only through the analysis of two-color light curves of Be stars that cover a few years and show ``bump-like'' magnitude excesses. The form of the bump depends on the dynamical state of the disk during the whole process of construction and dissipation. We show that the state of the disk can be extracted from two-color light curves by fitting theoretical curves, derived from a grid of dynamical models that we computed, to the observed light curves. The ? viscosity parameter works as a time scaling parameter, and is also obtained in the process of fitting, for each Be star.

Rímulo, L. R.; Carciofi, A. C.; Haubois, X.; Rivinius, T.

2014-10-01

273

Estimation of volume flow in curved tubes based on analytical and computational analysis of axial velocity profiles  

NASA Astrophysics Data System (ADS)

To monitor biomechanical parameters related to cardiovascular disease, it is necessary to perform correct volume flow estimations of blood flow in arteries based on local blood velocity measurements. In clinical practice, estimates of flow are currently made using a straight-tube assumption, which may lead to inaccuracies since most arteries are curved. Therefore, this study will focus on the effect of curvature on the axial velocity profile for flow in a curved tube in order to find a new volume flow estimation method. The study is restricted to steady flow, enabling the use of analytical methods. First, analytical approximation methods for steady flow in curved tubes at low Dean numbers (Dn) and low curvature ratios (?) are investigated. From the results a novel volume flow estimation method, the cos ?-method, is derived. Simulations for curved tube flow in the physiological range (1?Dn?1000 and 0.01???0.16) are performed with a computational fluid dynamics (CFD) model. The asymmetric axial velocity profiles of the analytical approximation methods are compared with the velocity profiles of the CFD model. Next, the cos ?-method is validated and compared with the currently used Poiseuille method by using the CFD results as input. Comparison of the axial velocity profiles of the CFD model with the approximations derived by Topakoglu [J. Math. Mech. 16, 1321 (1967)] and Siggers and Waters [Phys. Fluids 17, 077102 (2005)] shows that the derived velocity profiles agree very well for Dn?50 and are fair for 50100), no analytical approximation method exists. In the position of the maximum axial velocity, a shift toward the inside of the curve is observed for low Dean numbers, while for high Dean numbers, the position of the maximum velocity is located at the outer curve. When the position of the maximum velocity of the axial velocity profile is given as a function of the Reynolds number, a "zero-shift point" is found at Re=21.3. At this point the shift in the maximum axial velocity to the outside of the curve, caused by the difference in axial pressure gradient, balances the shift to the inside of the curve, caused by the centrifugal forces (radial pressure gradient). Comparison of the volume flow estimation of the cos ?-method with the Poiseuille method shows that for Dn?100 the Poiseuille method is sufficient, but for Dn?100 the cos ?-method estimates the volume flow nearly three times better. For ? =0.01 the maximum deviation from the exact flow is 4% for the cos ?-method, while this is 12.7% for the Poiseuille method in the plane of symmetry. The axial velocity profile measured at a certain angle from the symmetry plane results in a maximum estimation error of 6.2% for Dn=1000 and ? =0.16. The results indicate that the estimation of the volume flow through a curved tube from a given asymmetrical axial velocity profile is more precise with the cos ?-method than the Poiseuille method, which is currently used in clinical practice.

Verkaik, A. C.; Beulen, B. W. A. M. M.; Bogaerds, A. C. B.; Rutten, M. C. M.; van de Vosse, F. N.

2009-02-01

274

Impact of recession on Swiss pension program.  

PubMed

Legislation drafted in Switzerland in 1975--77 aims at countering the effects of inflation and recession by bringing increased revenues into the system, reducing expenditures, devising a mechanism to adjust pensions automatically, and improving income maintenance for the unemployed. The proposed legislation to place the social security system on a sound financial basis now needs voter approval in a referendum. Swiss voters meanwhile rejected (in mid-1977) a government-proposed value-added tax designed to finance increasing government contributions during 1978-82. Still to be resolved, therefore, is the problem of how the government will finance higher contributions and still achieve its staged goal of a balanced budget. PMID:644419

McArdle, F B

1978-04-01

275

Analysis of the Effect of Light and Temperature on the Fluence Response Curves for Germination of Rumex obtusifolius  

PubMed Central

Both red light (10 minutes) and 35°C treatment (60 minutes) stimulate the germination of seeds of Rumex obtusifolius otherwise maintained in darkness at 25°C. Fluence response curves were determined for the effect of red light to stimulate germination of seeds with and without 35°C treatment. The endogenous far-red absorbing form (Pfr) level in the seeds was determined using short saturating fluences of wavelengths of light which maintain different proportions of phytochrome as Pfr at equilibrium. In the seed batches investigated, the endogenous Pfr level was found to be 4% or less of the total phytochrome. High dark germination after 35°C treatment does not result from an increase in sensitivity of the whole population to Pfr. Calculated fluence response curves for germination which best fit the experimental data suggest that seeds germinate in darkness after 35°C treatment because of a nonphytochrome-related process (overriding factor). PMID:16664125

Takaki, Massanori; Heeringa, Gerda H.; Cone, John W.; Kendrick, Richard E.

1985-01-01

276

Analysis of the Effect of Light and Temperature on the Fluence Response Curves for Germination of Rumex obtusifolius.  

PubMed

Both red light (10 minutes) and 35 degrees C treatment (60 minutes) stimulate the germination of seeds of Rumex obtusifolius otherwise maintained in darkness at 25 degrees C. Fluence response curves were determined for the effect of red light to stimulate germination of seeds with and without 35 degrees C treatment. The endogenous far-red absorbing form (Pfr) level in the seeds was determined using short saturating fluences of wavelengths of light which maintain different proportions of phytochrome as Pfr at equilibrium. In the seed batches investigated, the endogenous Pfr level was found to be 4% or less of the total phytochrome. High dark germination after 35 degrees C treatment does not result from an increase in sensitivity of the whole population to Pfr. Calculated fluence response curves for germination which best fit the experimental data suggest that seeds germinate in darkness after 35 degrees C treatment because of a nonphytochrome-related process (overriding factor). PMID:16664125

Takaki, M; Heeringa, G H; Cone, J W; Kendrick, R E

1985-03-01

277

Testing Equality of Several Functions: Analysis of Single-Unit Firing Rate Curves Across Multiple Experimental Conditions  

Microsoft Academic Search

Abstract We consider the problem of comparing noisy functions, here trial-averaged neuronal firing-rate curves, across multiple experimental conditions. Of interest are comparisons both within neurons and also among populations of individually-recorded neurons. We propose likelihood ratio tests to perform comparisons either pointwise or globally over the entire experimental time. A simulation study of power demonstrates the strength of these tests

Sam Behseta; E. Kass; D avid E. Moorman; Carl R. Olson

278

Television Viewing and Adolescents’ Judgment of Sexual Request Scripts: A Latent Growth Curve Analysis in Early and Middle Adolescence  

Microsoft Academic Search

A longitudinal study was conducted to explore the relationship between television viewing and beliefs about expressing sexual\\u000a desire in dating situations. In three consecutive years, a panel of early adolescents (N?=?883) and a panel of middle adolescents (N?=?651) rated the effectiveness of a sexual approach and a romantic approach. Latent growth curve analyses indicate that between\\u000a the ages of 12

Steven Eggermont

2006-01-01

279

[The decline in population growth, income distribution, and economic recession].  

PubMed

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

Banguero, H

1983-05-01

280

Standard Mastery Curves and Skew Curves.  

ERIC Educational Resources Information Center

The objective of the study is to convince educational researchers of the necessity for "standard mastery curves" for the graphical representation of scores on summative tests for a group of students. Attention is drawn to the study of theoretical and empirical skew curves in education and biology. Use of standard mastery curves and study of skew…

Warries, Egbert

281

Interactive aesthetic curve segments  

Microsoft Academic Search

To meet highly aesthetic requirements in in- dustrial design and styling, we propose a new category of aesthetic curve segments. To achieve these aesthetic requirements, we use curves whose logarithmic curvature histograms(LCH) are represented by straight lines. We call such curves aesthetic curves. We identify the overall shapes of aesthetic curves depending on the slope of LCH ?, by imposing

Norimasa Yoshida; Takafumi Saito

2006-01-01

282

Parents' Victory in Reclaiming Recess for Their Children  

ERIC Educational Resources Information Center

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…

Zygmunt-Fillwalk, Eva; Bilello, Teresa Evanko

2005-01-01

283

Reducing Aerodynamic Resistance Holes with Annular Ribs and Recesses.  

National Technical Information Service (NTIS)

The article describes means of reducing the aerodynamic resistance of holes with annular ribs and recesses. One way is to make the edge of the opening turned toward the stream rounded. The principle of action of annular fins and recesses are explained and...

K. I. Khanzhonkov

1966-01-01

284

Drinking In the Age of the Great Recession  

Microsoft Academic Search

The United States has experienced the most severe economic crisis since the Great Depression. This paper presents an instrument (Life Change Consequences of the Great Recession; LCCGR) depicting work and personal life-related stressors reflecting the enduring effects of the Great Recession. A national sample of 663 respondents completed a mail survey including this instrument and measures of drinking outcomes. Multiple

Judith A. Richman; Kathleen M. Rospenda; Timothy P. Johnson; Young Ilk Cho; Ganga Vijayasira; Lea Cloninger; Jennifer M. Wolff

2012-01-01

285

Relating Streamflow Recession to Soil and Watershed Properties  

Microsoft Academic Search

By exploring the empirical relationship between streamflow recession data from USGS streamgauges and soils data from the Soil Survey Geographic (SSURGO) Database, we test the general hypothesis that a relationship exists between soil properties derived from soil data integrated across a watershed and streamflow recession parameters. This empirical study provides a background for developing a priori parameters with SSURGO soil

C. Bandaragoda; D. Tarboton; R. Woods; J. Boettinger

2007-01-01

286

Autosomal recessive forms of hereditary motor and sensory neuropathy  

Microsoft Academic Search

Six families are described with hereditary motor and sensory neuropathy (HMSN) of probable autosomal recessive inheritance. Four of these were classified as HMSN type I and two as type II. The consanguinity rate in this series was high, suggesting that these recessive genes are rare. In comparison with the dominantly inherited forms of these disorders, the mean age of onset

A E Harding; P K Thomas

1980-01-01

287

The Impact of the Recession on College Students  

ERIC Educational Resources Information Center

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…

Berg-Cross, Linda; Green, Rodney

2010-01-01

288

Withholding Recess from Elementary School Students: Policies Matter  

ERIC Educational Resources Information Center

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…

Turner, Lindsey; Chriqui, Jamie F.; Chaloupka, Frank J.

2013-01-01

289

Mechanisms of Disease: autosomal dominant and recessive polycystic kidney diseases  

Microsoft Academic Search

Autosomal dominant polycystic kidney disease and autosomal recessive polycystic kidney disease are the best known of a large family of inherited diseases characterized by the development of renal cysts of tubular epithelial cell origin. Autosomal dominant and recessive polycystic kidney diseases have overlapping but distinct pathogeneses. Identification of the causative mutated genes and elucidation of the function of their encoded

Peter C Harris; Vicente E Torres

2006-01-01

290

Quantitative analysis of electrophoresis data: novel curve fitting methodology and its application to the determination of a protein-DNA binding constant.  

PubMed Central

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

Shadle, S E; Allen, D F; Guo, H; Pogozelski, W K; Bashkin, J S; Tullius, T D

1997-01-01

291

NMR for direct determination of K(m) and V(max) of enzyme reactions based on the Lambert W function-analysis of progress curves.  

PubMed

(1)H NMR spectroscopy was used to follow the cleavage of sucrose by invertase. The parameters of the enzyme's kinetics, K(m) and V(max), were directly determined from progress curves at only one concentration of the substrate. For comparison with the classical Michaelis-Menten analysis, the reaction progress was also monitored at various initial concentrations of 3.5 to 41.8mM. Using the Lambert W function the parameters K(m) and V(max) were fitted to obtain the experimental progress curve and resulted in K(m)=28mM and V(max)=13?M/s. The result is almost identical to an initial rate analysis that, however, costs much more time and experimental effort. The effect of product inhibition was also investigated. Furthermore, we analyzed a much more complex reaction, the conversion of farnesyl diphosphate into (+)-germacrene D by the enzyme germacrene D synthase, yielding K(m)=379?M and k(cat)=0.04s(-1). The reaction involves an amphiphilic substrate forming micelles and a water insoluble product; using proper controls, the conversion can well be analyzed by the progress curve approach using the Lambert W function. PMID:22079737

Exnowitz, Franziska; Meyer, Bernd; Hackl, Thomas

2012-03-01

292

New Observations of the Martian Northern Seasonal Cap Recession with MARCI  

NASA Astrophysics Data System (ADS)

Data from the 2008 north cap recession has been analyzed and compared to data from the 2000 recession. The recession rate was found to be very similar for the two years but the 2008 recession began earlier in the year compared to the 2000 recession.

Dixon, E. M.; Calvin, W. M.; James, P. B.; Cantor, B. A.

2012-03-01

293

Atlas of fatigue curves  

SciTech Connect

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.

Boyer, H.E.

1986-01-01

294

GNAT1 Associated with Autosomal Recessive Congenital Stationary Night Blindness  

PubMed Central

Purpose. Congenital stationary night blindness is a nonprogressive retinal disorder manifesting as impaired night vision and is generally associated with other ocular symptoms, such as nystagmus, myopia, and strabismus. This study was conducted to further investigate the genetic basis of CSNB in a consanguineous Pakistani family. Methods. A consanguineous family with multiple individuals manifesting cardinal symptoms of congenital stationary night blindness was ascertained. All family members underwent detailed ophthalmic examination, including fundus photographic examination and electroretinography. Blood samples were collected and genomic DNA was extracted. Exclusion and genome-wide linkage analyses were completed and two-point LOD scores were calculated. Bidirectional sequencing of GNAT1 was completed, and quantitative expression of Gnat1 transcript levels were investigated in ocular tissues at different postnatal intervals. Results. The results of ophthalmic examinations were suggestive of early-onset stationary night blindness with no extraocular anomalies. The genome-wide scan localized the critical interval to chromosome 3, region p22.1-p14.3, with maximum two-point LOD scores of 3.09 at ? = 0, flanked by markers D3S3522 and D3S1289. Subsequently, a missense mutation in GNAT1, p.D129G, was identified, which segregated within the family, consistent with an autosomal recessive mode of inheritance, and was not present in 192 ethnically matched control chromosomes. Expression analysis suggested that Gnat1 is expressed at approximately postnatal day (P)7 and is predominantly expressed in the retina. Conclusions. These data suggest that a homozygous missense mutation in GNAT1 is associated with autosomal recessive stationary night blindness. PMID:22190596

Naeem, Muhammad Asif; Chavali, Venkata R. M.; Ali, Shahbaz; Iqbal, Muhammad; Riazuddin, Saima; Khan, Shaheen N.; Husnain, Tayyab; Sieving, Paul A.; Ayyagari, Radha; Riazuddin, Sheikh; Hejtmancik, J. Fielding

2012-01-01

295

Adolescents' physical activity at recess and actions to promote a physically active school day in four Finnish schools.  

PubMed

The national Finnish Schools on the Move programme support schools with their individual plans to promote school-based physical activity (PA). We examined the changes in adolescents' recess and overall PA in four lower secondary schools and described the school actions to promote students' PA and the local contact persons' perceptions of the effects. Recess and overall PA were assessed four times by anonymous questionnaires from students in grades 7-9 (n = 789) in 2010-12, and local contact persons (n = 7) provided information on school actions with diaries, interviews and surveys. Student data were analysed with descriptive statistics and chi-square tests, and school actions data were analysed with quantitative content analysis. The proportion of students who participated in physical activities at recess at least sometimes increased from 30% to 49% in physically active play and from 33% to 42% in ball games, mostly due to improvements in males' participation. Females' participation in recess activities increased in two schools with gender-specific physical activities or facilities. Overall PA levels declined slightly. Organized recess activities, student recess activators and equipment provision and sports facilities development were considered to have affected students' PA positively. Solutions for getting females more physically active in the school setting are needed. PMID:24906635

Haapala, H L; Hirvensalo, M H; Laine, K; Laakso, L; Hakonen, H; Lintunen, T; Tammelin, T H

2014-10-01

296

Curves of constant width  

Microsoft Academic Search

Curves of constant width have the same breadth regardless of how they are rotated. Highly noncircular curves with this property may be constructed geometrically. Such curves make good rollers, manhole covers, and allow one to drill nearly square holes.

James A. Flaten

1999-01-01

297

Curves of constant width  

NASA Astrophysics Data System (ADS)

Curves of constant width have the same breadth regardless of how they are rotated. Highly noncircular curves with this property may be constructed geometrically. Such curves make good rollers, manhole covers, and allow one to drill nearly square holes.

Flaten, James A.

1999-10-01

298

Arbitrarily Curved and Twisted Space Beams. Ph.D. Thesis - Va. Polytech. Inst. and State Univ.; [Elastic Deformation, Stress Analysis  

NASA Technical Reports Server (NTRS)

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.

Hunter, W. F.

1974-01-01

299

A novel mutation in the transglutaminase-1 gene in an autosomal recessive congenital ichthyosis patient.  

PubMed

Structure-function implication on a novel homozygous Trp250/Gly mutation of transglutaminase-1 (TGM1) observed in a patient of autosomal recessive congenital ichthyosis is invoked from a bioinformatics analysis. Structural consequences of this mutation are hypothesized in comparison to homologous enzyme human factor XIIIA accepted as valid in similar structural analysis and are projected as guidelines for future studies at an experimental level on TGM1 thus mutated. PMID:25180191

Vaigundan, D; Kalmankar, Neha V; Krishnappa, J; Gowda, N Yellappa; Kutty, A V M; Krishnaswamy, Patnam R

2014-01-01

300

Detection of a Knockdown Resistance Mutation Associated with Permethrin Resistance in the Body Louse Pediculus humanus corporis by Use of Melting Curve Analysis Genotyping  

PubMed Central

Louse-borne diseases are prevalent in the homeless, and body louse eradication has thus far been unsuccessful in this population. We aim to develop a rapid and robust genotyping method usable in large field-based clinical studies to monitor permethrin resistance in the human body louse Pediculus humanus corporis. We assessed a melting curve analysis genotyping method based on real-time PCR using hybridization probes to detect the M815I-T917I-L920F knockdown resistance (kdr) mutation in the paraorthologous voltage-sensitive sodium channel (VSSC) ? subunit gene, which is associated with permethrin resistance. The 908-bp DNA fragment of the VSSC gene, encoding the ? subunit of the sodium channel and encompassing the three mutation sites, was PCR sequenced from 65 lice collected from a homeless population. We noted a high prevalence of the 3 indicated mutations in the body lice collected from homeless people (100% for the M815I and L920F mutations and 56.73% for the T917I mutation). These results were confirmed by melting curve analysis genotyping, which had a calculated sensitivity of 100% for the M815I and T917I mutations and of 98% for the L920F mutation. The specificity was 100% for M815I and L920F and 96% for T917I. Melting curve analysis genotyping is a fast, sensitive, and specific tool that is fully compatible with the analysis of a large number of samples in epidemiological surveys, allowing the simultaneous genotyping of 96 samples in just over an hour (75 min). Thus, it is perfectly suited for the epidemiological monitoring of permethrin resistance in human body lice in large-scale clinical studies. PMID:22573588

Drali, Rezak; Benkouiten, Samir; Badiaga, Sekene; Bitam, Idir

2012-01-01

301

Construction of an Earth Model: Analysis of Exoplanet Light Curves and Mapping the Next Earth with the New Worlds Observer  

NASA Astrophysics Data System (ADS)

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 ~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 ? 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.

Oakley, P. H. H.; Cash, W.

2009-08-01

302

CONSTRUCTION OF AN EARTH MODEL: ANALYSIS OF EXOPLANET LIGHT CURVES AND MAPPING THE NEXT EARTH WITH THE NEW WORLDS OBSERVER  

SciTech Connect

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.

Oakley, P. H. H.; Cash, W. [Center for Astrophysics and Space Astronomy, University of Colorado, Boulder, CO, 80309 (United States)], E-mail: Phil.Oakley@Colorado.edu

2009-08-01

303

Factors influencing the recession rate of Niagara Falls since the 19th century  

NASA Astrophysics Data System (ADS)

The rate of recession of Niagara Falls (Horseshoe and American Falls) in northeastern North America has been documented since the 19th century; it shows a decreasing trend from ca. 1 m y - 1 a century ago to ca. 0.1 m y - 1 at present. Reduction of the flow volume in the Niagara River due to diversion into bypassing hydroelectric schemes has often been taken to be the factor responsible, but other factors such as changes in the waterfall shape could play a role and call for a quantitative study. Here, we examine the effect of physical factors on the historically varying recession rates of Niagara Falls, using an empirical equation which has previously been proposed based on a non-dimensional multiparametric model which incorporates flow volume, waterfall shape and bedrock strength. The changes in recession rates of Niagara Falls in the last century are successfully modeled by this empirical equation; these changes are caused by variations in flow volume and lip length. This result supports the validity of the empirical equation for waterfalls in rivers carrying little transported sediment. Our analysis also suggests that the decrease in the recession rate of Horseshoe Falls is related to both artificial reduction in river discharge and natural increase in waterfall lip length, whereas that of American Falls is solely due to the reduction in flow volume.

Hayakawa, Yuichi S.; Matsukura, Yukinori

2009-09-01

304

Economic recession and mental health: an overview.  

PubMed

Effects of the current global economic downturn on population mental health will emerge in the years ahead. Judging from earlier experience of financial crises in various parts of the world, stresses associated with rising unemployment, poverty and social insecurity will lead to upward trends in many national suicide rates, as well as to less readily charted increase in the prevalence of psychiatric illness, alcohol-related disorders and illicit drug use. At the same time, mental health services are being cut back as part of government austerity programs. Budget cuts will thus affect psychiatric services adversely just when economic stressors are raising the levels of need and demand in affected populations. Proactive fiscal and social policies could, however, help to mitigate the health consequences of recession. Evidence- based preventive measures include active labor market and family support programs, regulation of alcohol prices and availability, community care for known high-risk groups, and debt relief projects. Economic mental health care could best be achieved, not by decimating services but by planning and deploying these to meet the needs of defined area populations. PMID:21968374

Cooper, Brian

2011-01-01

305

Urbanization and the global malaria recession  

PubMed Central

Background The past century has seen a significant contraction in the global extent of malaria transmission, resulting in over 50 countries being declared malaria free, and many regions of currently endemic countries eliminating the disease. Moreover, substantial reductions in transmission have been seen since 1900 in those areas that remain endemic today. Recent work showed that this malaria recession was unlikely to have been driven by climatic factors, and that control measures likely played a significant role. It has long been considered, however, that economic development, and particularly urbanization, has also been a causal factor. The urbanization process results in profound socio-economic and landscape changes that reduce malaria transmission, but the magnitude and extent of these effects on global endemicity reductions are poorly understood. Methods Global data at subnational spatial resolution on changes in malaria transmission intensity and urbanization trends over the past century were combined to examine the relationships seen over a range of spatial and temporal scales. Results/Conclusions A consistent pattern of increased urbanization coincident with decreasing malaria transmission and elimination over the past century was found. Whilst it remains challenging to untangle whether this increased urbanization resulted in decreased transmission, or that malaria reductions promoted development, the results point to a close relationship between the two, irrespective of national wealth. The continuing rapid urbanization in malaria-endemic regions suggests that such malaria declines are likely to continue, particularly catalyzed by increasing levels of direct malaria control. PMID:23594701

2013-01-01

306

Recessions, Job Loss, and Mortality Among Older US Adults.  

PubMed

Objectives. We analyzed how recessions and job loss jointly shape mortality risks among older US adults. Methods. We used data for 50 states from the Health and Retirement Study and selected individuals who were employed at ages 45 to 66 years during 1992 to 2011. We assessed whether job loss affects mortality risks, whether recessions moderate the effect of job loss on mortality, and whether individuals who do and do not experience job loss are differentially affected by recessions. Results. Compared with individuals not experiencing job loss, mortality risks among individuals losing their job in a recession were strongly elevated (hazard ratio?=?1.6; 95% confidence interval?=?1.1, 2.3). Job loss during normal times or booms is not associated with mortality. For employed workers, we found a reduction in mortality risks if local labor market conditions were depressed, but this result was not consistent across different model specifications. Conclusions. Recessions increase mortality risks among older US adults who experience job loss. Health professionals and policymakers should target resources to this group during recessions. Future research should clarify which health conditions are affected by job loss during recessions and whether access to health care following job loss moderates this relation. PMID:25211731

Noelke, Clemens; Beckfield, Jason

2014-11-01

307

Pre-curving analysis of an opening crack in a magnetoelectroelastic strip under in-plane impact loadings  

NASA Astrophysics Data System (ADS)

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.

Hu, Keqiang; Chen, Zengtao

2012-12-01

308

National Curve Bank  

NSDL National Science Digital Library

The National Curve Bank displays representations of two- and three-dimensional curves. Geometrical, algebraic, and historical aspects of curves are included. Educators and students have access to animations, interactions, java applets, Mathematica code, and more. Users may submit curves. Materials are reveiwed and selected by faculty at Cal State Los Angeles.

2009-03-01

309

Characterizations of Special Curves  

E-print Network

In this study, the new characterizations of special curves are investigated without using the curvatures of these special curves: general helices, slant helices, Bertrand curves, Mannheim curves. The curvatures are given by the help of the norms of the derivatives of Frenet vectors.

Yayli, Yusuf

2012-01-01

310

Economic recession and headache-related hospital admissions.  

PubMed

Incidence of headaches across different regions and its relationship to unemployment rates in the United States before and during an economic recession was evaluated. Years 2008 and 2009 were determined as recessionary period. Headache-related admissions, particularly the uncomplicated headaches, increased significantly during recession. Proportion of women with headaches has increased and the age group of 25-54 years was the most affected during the recession. The hospital charges have increased even though the average length and charge of stay decreased. These findings are consistent with our understanding of effects of stress and unemployment on psychological and physical health. PMID:23822548

Chinta, Ravi; Rao, M B; Narendran, Vivek; Malla, Ganesh; Joshi, Hem

2013-01-01

311

Autosomal Recessive Anhidrotic Ectodermal Dysplasia: A Rare Entity  

PubMed Central

We describe a case of anhidrotic ectodermal dysplasia (AED) with an autosomal recessive mode of inheritance, a very rare entity, in a 2-year-old female child of two asymptomatic, consanguineous parents. Their previous child also had a similar condition. Autosomal recessive AED (AR-AED) can have its full expression both in males and females and it is clinically indistinguishable from the x-linked recessive AED (XL-AED), which is the most common type of ectodermal dysplasia. Unlike the partially symptomatic carriers of XL-AED, the heterozygotes of AR-AED are phenotypically asymptomatic. PMID:25071285

Ghosh, Sangita; Ghosh, Epsita; Dayal, Surabhi

2014-01-01

312

Understanding curved detonation waves  

SciTech Connect

A wave curve is the set of final states to which an initial state may be connected by a traveling wave. In gas dynamics, for example, the wave curve consists of the shock Hugoniot curve for compressive waves and the rarefaction curve for expansive waves. In this paper, we discuss the wave curve for an undriven planar detonation and for general planar detonations. We then extend the wave curve concept to detonations in converging and diverging geometry. We also discuss the application of these wave curves to the numerical computation of detonation problems.

Bukiet, B.G. [New Jersey Inst. of Tech., Newark, NJ (United States). Dept. of Mathematics; Menikoff, R. [Los Alamos National Lab., NM (United States)

1992-10-01

313

Understanding curved detonation waves  

SciTech Connect

A wave curve is the set of final states to which an initial state may be connected by a traveling wave. In gas dynamics, for example, the wave curve consists of the shock Hugoniot curve for compressive waves and the rarefaction curve for expansive waves. In this paper, we discuss the wave curve for an undriven planar detonation and for general planar detonations. We then extend the wave curve concept to detonations in converging and diverging geometry. We also discuss the application of these wave curves to the numerical computation of detonation problems.

Bukiet, B.G. (New Jersey Inst. of Tech., Newark, NJ (United States). Dept. of Mathematics); Menikoff, R. (Los Alamos National Lab., NM (United States))

1992-01-01

314

Quantitative Fundus Autofluorescence in Recessive Stargardt Disease  

PubMed Central

Purpose. To quantify fundus autofluorescence (qAF) in patients with recessive Stargardt disease (STGD1). Methods. A total of 42 STGD1 patients (ages: 7–52 years) with at least one confirmed disease-associated ABCA4 mutation were studied. Fundus AF images (488-nm excitation) were acquired with a confocal scanning laser ophthalmoscope equipped with an internal fluorescent reference to account for variable laser power and detector sensitivity. The gray levels (GLs) of each image were calibrated to the reference, zero GL, magnification, and normative optical media density to yield qAF. Texture factor (TF) was calculated to characterize inhomogeneities in the AF image and patients were assigned to the phenotypes of Fishman I through III. Results. Quantified fundus autofluorescence in 36 of 42 patients and TF in 27 of 42 patients were above normal limits for age. Young patients exhibited the relatively highest qAF, with levels up to 8-fold higher than healthy eyes. Quantified fundus autofluorescence and TF were higher in Fishman II and III than Fishman I, who had higher qAF and TF than healthy eyes. Patients carrying the G1916E mutation had lower qAF and TF than most other patients, even in the presence of a second allele associated with severe disease. Conclusions. Quantified fundus autofluorescence is an indirect approach to measuring RPE lipofuscin in vivo. We report that ABCA4 mutations cause significantly elevated qAF, consistent with previous reports indicating that increased RPE lipofuscin is a hallmark of STGD1. Even when qualitative differences in fundus AF images are not evident, qAF can elucidate phenotypic variation. Quantified fundus autofluorescence will serve to establish genotype-phenotype correlations and as an outcome measure in clinical trials. PMID:24677105

Burke, Tomas R.; Duncker, Tobias; Woods, Russell L.; Greenberg, Jonathan P.; Zernant, Jana; Tsang, Stephen H.; Smith, R. Theodore; Allikmets, Rando; Sparrow, Janet R.; Delori, Francois C.

2014-01-01

315

Detection, measurement and prediction of shoreline recession in Accra, Ghana  

NASA Astrophysics Data System (ADS)

Coastal mapping, using various data capture and feature extraction techniques, has furthered understanding of trends in shoreline evolution by allowing calculation of accurate historic rates of change that subsequently enable the prediction of future shoreline positions through different modelling procedures. The results have helped influence coastal policy formulation and promoted the development of sustainable management practices in coastal regions throughout the developed world. However, sustainable coastal management is rarely practiced in developing countries, one of the fundamental reasons for this being a general lack of reliable and accurate historic data on shoreline position. Previous studies on the Ghanaian coastal region of Accra, where accurate and reliable geospatial data for analysis is scarce, have reported erosion rates of anything between two and eight metres per year. This high level of inconsistency in reported rates has hindered effective and sustainable coastal management. The research reported in this paper addresses this issue, using mapping data from 1904, 1974, 1996 and 2002 to estimate, by linear regression, shoreline recession in the Accra region. Predictions for the next 250 yr were then undertaken using a variety of techniques ranging from a process-based numerical model, SCAPE, to geometric approaches including historical trend analysis, the modified Bruun model and Sunamura's shore platform model. Uncertainties in the various input data were accounted for, including historic recession rates, rock strength, sediment content and, importantly, future sea-level rise under different climate change scenarios. The mean historic rate of erosion in the Accra region was found to be 1.13 m/yr(±0.17 m/yr), significantly less than previously reported, though still very high. Subsequent predictions were used to identify a series of significant economic, ecological and social features at risk, and to estimate when they will most likely be lost to erosion if left unprotected. The case study illustrates that, provided suitable predictive models are selected and the uncertainties involved in working with limited data sets are dealt with appropriately, it is possible to provide statistical information in support of sustainable coastal management for developing countries in the face of a changing climate.

Appeaning Addo, K.; Walkden, M.; Mills, J. P.

316

Noise reduction methods in the analysis of near infrared lunar occultation light curves for high angular resolution measurements  

NASA Astrophysics Data System (ADS)

A lunar occultation (LO) technique in the near-infrared (NIR) provides angular resolution down to milliarcseconds for an occulted source, even with ground-based 1 m class telescopes. LO observations are limited to brighter objects because they require a high signal-to-noise ratio (S/N ~40) for proper extraction of angular diameter values. Hence, methods to improve the S/N ratio by reducing noise using Fourier and wavelet transforms have been explored in this study. A sample of 54 NIR LO light curves observed with the IR camera at Mt Abu Observatory has been used. It is seen that both Fourier and wavelet methods have shown an improvement in S/N compared to the original data. However, the application of wavelet transforms causes a slight smoothing of the fringes and results in a higher value for angular diameter. Fourier transforms which reduce discrete noise frequencies do not distort the fringe. The Fourier transform method seems to be effective in improving the S/N, as well as improving the model fit, particularly in the fainter regime of our sample. These methods also provide a better model fit for brighter sources in some cases, though there may not be a significant improvement in S/N.

Baug, Tapas; Chandrasekhar, Thyagarajan

2013-11-01

317

Development of skin conductance orienting, habituation, and reorienting from ages 3 to 8 years: a longitudinal latent growth curve analysis.  

PubMed

Little is known about the development of the skin conductance orienting response (SCOR) in childhood. This longitudinal study examines the effects of age on initial SCOR, habituation, and reorienting. Skin conductance responses to nonsignal auditory stimuli were recorded from 200 male and female children at five different time points (ages 3, 4, 5, 6, and 8 years). Longitudinal latent growth curve analyses were used to determine the trajectory of each SCOR measure during this period. Results indicated that (a) initial SCOR is present at age 3, increases thereafter to peak at age 6, and then levels off, (b) habituation is absent at age 3, but becomes apparent at age 4 years and increases thereafter with increasing age, (c) SC reorienting is absent from ages 3 to 8, and (d) boys and girls do not exhibit different developmental trajectories. Results suggest that from age 3 to 8 years, the transition from the functionally immature to mature neural network underlying orienting and habituation is a continuous process and may be related to children's cognitive development during this period. PMID:17666032

Gao, Yu; Raine, Adrian; Dawson, Michael E; Venables, Peter H; Mednick, Sarnoff A

2007-11-01

318

Growth Curve Models for the Analysis of Phenotype Arrays for a Systems Biology Overview of Yersinia pestis  

SciTech Connect

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.

Fodor, I K; Holtz-Morris, A E; McCutchen-Maloney, S L

2005-09-08

319

An analysis on the mechanism responsible for genesis of deformation of expiratory-gas-concentration curves in chickens.  

PubMed

Phenomena associated with a deformation of short-time occurrence and noticed on concentration curves of tidal O2 and CO2 were examined in adult hens sitting quietly in a cage or suspended in prone position. During the episode of deformation, a decrease in arterial oxygen-gas tension was apparent. It was associated with a slight increase in arterial carbon-dioxide-gas tension and a slight acidic shift of arterial blood pH. The episode was associated with increases in intrapressure of the interclavicular and bilateral abdominal air sacs. The tracheal expiratory-gas flow changed in pattern. Hypoventilation due to reduction in tidal volume or respiratory rate could not be detected during the episode. The episode was suddenly terminated at the hen's body movement induced spontaneously or by pinching the comb, at coughlike activity or at no obvious change in behavior in a quietly resting position. Deformation similar to the spontaneous one could be induced by 3 ml-water flushing into the trachea or 0.1% methacholine aerosol inhalation. The mechanism responsible for the genesis of deformation was discussed. It was presumed to be based upon some mechanism, such as mucous accumulation in the lung, rather than upon the pulmonary smooth-muscle contraction. PMID:6804876

Itabisashi, T

1981-01-01

320

31. DETAILED INTERIOR VIEW OF AUXILIARY LOCK, SHOWING RECESSES FOR ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. DETAILED INTERIOR VIEW OF AUXILIARY LOCK, SHOWING RECESSES FOR MITER GATE OPERATING MACHINERY IN LEFT FOREGROUND. LOOKING NORTHEAST (UPSTREAM) - Upper Mississippi River Nine-Foot Channel Project, Lock & Dam No. 25, Cap au Gris, Lincoln County, MO

321

Gonadal mosaicism as a rare cause of autosomal recessive inheritance.  

PubMed

Autosomal recessive diseases are typically caused by the biparental inheritance of familial mutant alleles. Unusual mechanisms by which the recessiveness of a mutant allele is unmasked include uniparental isodisomy and the occurrence of a de novo chromosomal rearrangement that disrupts the other allele. Gonadal mosaicism is a condition in which a postfertilization mutation is confined to the gamete precursors and is not detected in somatic tissues. Gonadal mosaicism is known to give the impression of autosomal recessive inheritance when recurrence of an autosomal-dominant condition among offspring of phenotypically normal parents is observed. Here, we report an extremely rare event in which maternal gonadal mosaicism for a recessive mutation in COL4A4 caused the recurrence of Alport syndrome within a consanguineous family. Such rare occurrence should be taken into account when analyzing pedigrees both for clinical and research purposes. PMID:23551117

Anazi, S; Al-Sabban, E; Alkuraya, F S

2014-03-01

322

Ecology and Management of the Spring Snowmelt Recession  

NSDL National Science Digital Library

We present a conceptual model for the ecology of the spring snowmelt recession based on the natural flow regime that relates the quantifiable components of magnitude, timing, and rate of change to abiotic and biotic factors that govern riverine processes. We find that shifts in the magnitude of the recession largely affect abiotic channel conditions, whereas shifts in the timing of the snowmelt primarily affect biotic conditions. Shifts in the rate of change affect both abiotic and biotic conditions, creating the largest observed changes to the stream ecosystem. We discuss these components with regard to the success of riverine species in California's Mediterranean-montane environment. We then present two scenarios of change to the spring snowmelt recessionâÂÂeffects of flow regulation and climate warmingâÂÂand discuss their potential implications for riverine ecology. Our conceptual model can help guide watershed stakeholders toward a better understanding of the impacts of changing spring recession conditions on stream ecosystems.

Sarah Yarnell (University of California, Davis;Center for Watershed Studies)

2010-02-01

323

A Six-Node Curved Triangular Element and a Four-Node Quadrilateral Element for Analysis of Laminated Composite Aerospace Structures  

NASA Technical Reports Server (NTRS)

Mathematical development and some computed results are presented for Mindlin plate and shell elements, suitable for analysis of laminated composite and sandwich structures. These elements use the conventional 3 (plate) or 5 (shell) nodal degrees of freedom, have no communicable mechanisms, have no spurious shear energy (no shear locking), have no spurious membrane energy (no membrane locking) and do not require arbitrary reduction of out-of-plane shear moduli or under-integration. Artificial out-of-plane rotational stiffnesses are added at the element level to avoid convergence problems or singularity due to flat spots in shells. This report discusses a 6-node curved triangular element and a 4-node quadrilateral element. Findings show that in regular rectangular meshes, the Martin-Breiner 6-node triangular curved shell (MB6) is approximately equivalent to the conventional 8-node quadrilateral with integration. The 4-node quadrilateral (MB4) has very good accuracy for a 4-node element, and may be preferred in vibration analysis because of narrower bandwidth. The mathematical developments used in these elements, those discussed in the seven appendices, have been applied to elements with 3, 4, 6, and 10 nodes and can be applied to other nodal configurations.

Martin, C. Wayne; Breiner, David M.; Gupta, Kajal K. (Technical Monitor)

2004-01-01

324

Autosomal recessive polycystic kidney disease: long-term outcome of neonatal survivors  

Microsoft Academic Search

.  ?Autosomal recessive polycystic kidney disease causes renal and hepatic dysfunction in childhood. We describe the clinical\\u000a outcome of 52 children with this diagnosis born between 1950 and 1993. Currently 23 are alive, 24 dead and 5 have been lost\\u000a to follow-up; 1 has been dialysed and 7 transplanted. Life-table analysis of the patients surviving the 1st month of life\\u000a revealed

Sushmita Roy; Michael J. Dillon; Richard S. Trompeter; T. Martin Barratt

1997-01-01

325

Mutations of ESPN cause autosomal recessive deafness and vestibular dysfunction  

Microsoft Academic Search

We mapped a human deafness locus DFNB36 to chromosome 1p36.3 in two consanguineous families segregating recessively inherited deafness and vestibular areflexia. This phenotype co-segregates with either of two frameshift mutations, 1988delAGAG and 2469delGTCA, in ESPN, which encodes a calcium-insensitive actin-bundling protein called espin. A recessive mutation of ESPN is known to cause hearing loss and vestibular dysfunction in the jerker

S Naz; A J Griffith; S Riazuddin; L L Hampton; J F Battey; S N Khan; E R Wilcox; T B Friedman

2004-01-01

326

Children's Physical Activity during Recess and Outside of School  

ERIC Educational Resources Information Center

The purpose of this study was to examine children's physical activity during recess and outside of school. Third-, fourth-, and fifth-grade students (N = 270; 121 boys, age = 9.5 plus or minus 0.9 years; 150 girls, age = 9.6 plus or minus 0.9 years) wore sealed pedometers during a 15-minute recess period and outside of school for 4 consecutive…

Beighle, Aaron; Morgan, Charles F.; Le Masurier, Guy; Pangrazi, Robert P.

2006-01-01

327

Gonadal (ovarian) dysgenesis in 46,XX individuals: Frequency of the autosomal recessive form  

SciTech Connect

Gonadal (ovarian) dysgenesis with normal chromosomes (46,XX) clearly is a heterogeneous condition. In some forms, the defect is restricted to the gonads, whereas other affected females show neurosensory hearing loss (Perrault syndrome). In another form, brothers may have germ cell aplasia. Nongenetic causes exist as well. To elucidate the proportion of XX gonadal (ovarian) dysgenesis due to autosomal recessive genes, we analyzed published (N = 17) and unpublished (N = 8) families having at least two female offspring. Analysis was restricted to cases in whom ovarian failure was documented by the presence of streak ovaries (published cases) or elevated gonadotropins (unpublished cases). We reasoned that the closer to that segregation ratio expected for an autosomal recessive trait (0.25), the lower the frequency of nongenetic forms. Segregation analysis utilized standard correction for single ascertainment, with only females included in the preliminary analysis. The segregation ratio estimate was 0.16. Our results suggest that many 46,XX females with gonadal (ovarian) dysgenesis represent a disorder segregating as an autosomal recessive trait, placing sisters of these cases at a 25% risk for this disorder. 32 refs., 2 figs., 1 tab.

Meyers, C.M.; Boughman, J.A. [Univ. of Maryland, Baltimore, MD (United States)] [Univ. of Maryland, Baltimore, MD (United States); Rivas, M. [Univ. of Tennessee, Memphis, TN (United States)] [and others] [Univ. of Tennessee, Memphis, TN (United States); and others

1996-06-28

328

A New Type Curve Analysis for Shale Gas/Oil Reservoir Production Performance with Dual Porosity Linear System  

E-print Network

With increase of interest in exploiting shale gas/oil reservoirs with multiple stage fractured horizontal wells, complexity of production analysis and reservoir description have also increased. Different methods and models were used throughout...

Abdulal, Haider Jaffar

2012-02-14

329

Atmospheric Stability Impacts on Power Curves of Tall Wind Turbines - An Analysis of a West Coast North American Wind Farm  

SciTech Connect

Tall wind turbines, with hub heights at 80 m or above, can extract large amounts of energy from the atmosphere because they are likely to encounter higher wind speeds, but they face challenges given the complex nature of wind flow and turbulence at these heights in the boundary layer. Depending on whether the boundary layer is stable, neutral, or convective, the mean wind speed, direction, and turbulence properties may vary greatly across the tall turbine swept area (40 to 120 m AGL). This variability can cause tall turbines to produce difference amounts of power during time periods with identical hub height wind speeds. Using meteorological and power generation data from a West Coast North American wind farm over a one-year period, our study synthesizes standard wind park observations, such as wind speed from turbine nacelles and sparse meteorological tower observations, with high-resolution profiles of wind speed and turbulence from a remote sensing platform, to quantify the impact of atmospheric stability on power output. We first compare approaches to defining atmospheric stability. The standard, limited, wind farm operations enable the calculation only of a wind shear exponent ({alpha}) or turbulence intensity (I{sub U}) from cup anemometers, while the presence at this wind farm of a SODAR enables the direct observation of turbulent kinetic energy (TKE) throughout the turbine rotor disk. Additionally, a nearby research meteorological station provided observations of the Obukhov length, L, a direct measure of atmospheric stability. In general, the stability parameters {alpha}, I{sub U}, and TKE are in high agreement with the more physically-robust L, with TKE exhibiting the best agreement with L. Using these metrics, data periods are segregated by stability class to investigate power performance dependencies. Power output at this wind farm is highly correlated with atmospheric stability during the spring and summer months, while atmospheric stability exerts little impact on power output during the winter and autumn periods. During the spring and summer seasons, power output for a given wind speed was significantly higher during stable conditions and significantly lower during strongly convective conditions: power output differences approached 20% between stable and convective regimes. The dependency of stability on power output was apparent only when both turbulence and the shape of the wind speed profile were considered. Turbulence is one of the mechanisms by which atmospheric stability affects a turbine's power curve at this particular site, and measurements of turbulence can yield actionable insights into wind turbine behavior.

Wharton, S; Lundquist, J K

2010-02-22

330

Comparative Analysis of the Volatile Components of Agrimonia eupatoria from Leaves and Roots by Gas Chromatography-Mass Spectrometry and Multivariate Curve Resolution  

PubMed Central

Gas chromatography-mass spectrometry and multivariate curve resolution were applied to the differential analysis of the volatile components in Agrimonia eupatoria specimens from different plant parts. After extracted with water distillation method, the volatile components in Agrimonia eupatoria from leaves and roots were detected by GC-MS. Then the qualitative and quantitative analysis of the volatile components in the main root of Agrimonia eupatoria was completed with the help of subwindow factor analysis resolving two-dimensional original data into mass spectra and chromatograms. 68 of 87 separated constituents in the total ion chromatogram of the volatile components were identified and quantified, accounting for about 87.03% of the total content. Then, the common peaks in leaf were extracted with orthogonal projection resolution method. Among the components determined, there were 52 components coexisting in the studied samples although the relative content of each component showed difference to some extent. The results showed a fair consistency in their GC-MS fingerprint. It was the first time to apply orthogonal projection method to compare different plant parts of Agrimonia eupatoria, and it reduced the burden of qualitative analysis as well as the subjectivity. The obtained results proved the combined approach powerful for the analysis of complex Agrimonia eupatoria samples. The developed method can be used to further study and quality control of Agrimonia eupatoria. PMID:24286016

Feng, Xiao-Liang; He, Yun-biao; Liang, Yi-Zeng; Wang, Yu-Lin; Huang, Lan-Fang; Xie, Jian-Wei

2013-01-01

331

Recessive truncating titin gene, TTN, mutations presenting as centronuclear myopathy  

PubMed Central

Objective: To identify causative genes for centronuclear myopathies (CNM), a heterogeneous group of rare inherited muscle disorders that often present in infancy or early life with weakness and hypotonia, using next-generation sequencing of whole exomes and genomes. Methods: Whole-exome or -genome sequencing was performed in a cohort of 29 unrelated patients with clinicopathologic diagnoses of CNM or related myopathy depleted for cases with mutations of MTM1, DNM2, and BIN1. Immunofluorescence analyses on muscle biopsies, splicing assays, and gel electrophoresis of patient muscle proteins were performed to determine the molecular consequences of mutations of interest. Results: Autosomal recessive compound heterozygous truncating mutations of the titin gene, TTN, were identified in 5 individuals. Biochemical analyses demonstrated increased titin degradation and truncated titin proteins in patient muscles, establishing the impact of the mutations. Conclusions: Our study identifies truncating TTN mutations as a cause of congenital myopathy that is reported as CNM. Unlike the classic CNM genes that are all involved in excitation-contraction coupling at the triad, TTN encodes the giant sarcomeric protein titin, which forms a myofibrillar backbone for the components of the contractile machinery. This study expands the phenotypic spectrum associated with TTN mutations and indicates that TTN mutation analysis should be considered in cases of possible CNM without mutations in the classic CNM genes. PMID:23975875

Ceyhan-Birsoy, Ozge; Agrawal, Pankaj B.; Hidalgo, Carlos; Schmitz-Abe, Klaus; DeChene, Elizabeth T.; Swanson, Lindsay C.; Soemedi, Rachel; Vasli, Nasim; Iannaccone, Susan T.; Shieh, Perry B.; Shur, Natasha; Dennison, Jane M.; Lawlor, Michael W.; Laporte, Jocelyn; Markianos, Kyriacos; Fairbrother, William G.; Granzier, Henk

2013-01-01

332

Runs of homozygosity reveal highly penetrant recessive loci in schizophrenia  

PubMed Central

Evolutionarily significant selective sweeps may result in long stretches of homozygous polymorphisms in individuals from outbred populations. We developed whole-genome homozygosity association (WGHA) methodology to characterize this phenomenon in healthy individuals and to use this genomic feature to identify genetic risk loci for schizophrenia (SCZ). Applying WGHA to 178 SCZ cases and 144 healthy controls genotyped at 500,000 markers, we found that runs of homozygosity (ROHs), ranging in size from 200 kb to 15 mb, were common in unrelated Caucasians. Properties of common ROHs in healthy subjects, including chromosomal location and presence of nonancestral haplotypes, converged with prior reports identifying regions under selective pressure. This interpretation was further supported by analysis of multiethnic HapMap samples genotyped with the same markers. ROHs were significantly more common in SCZ cases, and a set of nine ROHs significantly differentiated cases from controls. Four of these 9 “risk ROHs” contained or neighbored genes associated with SCZ (NOS1AP, ATF2, NSF, and PIK3C3). Several of these risk ROHs were very rare in healthy subjects, suggesting that recessive effects of relatively high penetrance may explain a proportion of the genetic liability for SCZ. Other risk ROHs feature haplotypes that are also common in healthy individuals, possibly indicating a source of balancing selection. PMID:18077426

Lencz, Todd; Lambert, Christophe; DeRosse, Pamela; Burdick, Katherine E.; Morgan, T. Vance; Kane, John M.; Kucherlapati, Raju; Malhotra, Anil K.

2007-01-01

333

[Speed of information processing and fluid intelligence in advanced age. A secondary analysis of data of the Bonn Longitudinal Study of Aging based on "latent growth curve models"].  

PubMed

According to the "speed"-hypothesis of cognitive development, the slowing of information processing in old age is at the core of negative age differences in psychometric intelligence. The present study investigates the "speed"-hypothesis for fluid intelligence at the individual level using Latent Growth Curve Methodology. Data on 4 measurement points come from the Bonn Longitudinal Study of aging (N = 127, mean age 67.2, 53% women). Based on principal factor analysis, markers of mental speed were the WAIS Digit Symbol Test and a simple psychomotor task. As indicators of fluid intelligence the WAIS Object Assembly and Block Design were used. After separately fitting Latent Growth Curve Models for the trajectory of mental speed and fluid intelligence, a combined model showed no statistically significant improvement of fit for freeing the covariance between the two slope-factors. Interpreting this result, contrary to the "speed"-hypothesis the intraindividual change of fluid intelligence does not relate to the according change of mental speed. PMID:9610501

Zimprich, D

1998-04-01

334

Assessing the Impact of Family Process on Rural African American Adolescents' Competence and Behavior Using Latent Growth Curve Analysis  

ERIC Educational Resources Information Center

A study examines the long-term effects of a family process program on social and cognitive competence and aggressive and deviant behavior among rural African American adolescents. Results suggest that family processes influence the status and changes in adolescent competence and behavior, while analysis of covariant structures suggest that…

Toldson, Ivory A.

2006-01-01

335

Principal curves revisited  

Microsoft Academic Search

A principal curve (Hastie and Stuetzle, 1989) is a smooth curve passing through the ‘middle’ of a distribution or data cloud, and is a generalization of linear principal components. We give an alternative definition of a principal curve, based on a mixture model. Estimation is carried out through an EM algorithm. Some comparisons are made to the Hastie-Stuetzle definition.

Robert Tibshirani

1992-01-01

336

Mutation in MEOX1 gene causes a recessive Klippel-Feil syndrome subtype  

PubMed Central

Background Klippel-Feil syndrome (KFS) is characterized by the developmental failure of the cervical spine and has two dominantly inherited subtypes. Affected individuals who are the children of a consanguineous marriage are extremely rare in the medical literature, but the gene responsible for this recessive trait subtype of KFS has recently been reported. Results We identified a family with the KFS phenotype in which their parents have a consanguineous marriage. Radiological examinations revealed that they carry fusion defects and numerical abnormalities in the cervical spine, scoliosis, malformations of the cranial base, and Sprengel’s deformity. We applied whole genome linkage and whole-exome sequencing analysis to identify the chromosomal locus and gene mutated in this family. Whole genome linkage analysis revealed a significant linkage to chromosome 17q12-q33 with a LOD score of 4.2. Exome sequencing identified the G?>?A p.Q84X mutation in the MEOX1 gene, which is segregated based on pedigree status. Homozygous MEOX1 mutations have reportedly caused a similar phenotype in knockout mice. Conclusions Here, we report a truncating mutation in the MEOX1 gene in a KFS family with an autosomal recessive trait. Together with another recently reported study and the knockout mouse model, our results suggest that mutations in MEOX1 cause a recessive KFS phenotype in humans. PMID:24073994

2013-01-01

337

IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE, VOL. 21, NO. 1, JANUARY 1999 49 Automated B-Spline Curve Representation  

E-print Network

Automated B-Spline Curve Representation Incorporating MDL and Error-Minimizing Control Point Insertion, but despite the long existence of B-spline curve-fitting techniques, it is difficult to find a fully automated 2.1 Parameterization When handling image curves, the B-spline parameterization along the fitted

Cham, Tat Jen

338

High-Resolution DNA Melt Curve Analysis of the Clustered, Regularly Interspaced Short-Palindromic-Repeat Locus of Campylobacter jejuni  

Microsoft Academic Search

A novel method for genotyping the clustered, regularly interspaced short-palindromic-repeat (CRISPR) locus of Campylobacter jejuni is described. Following real-time PCR, CRISPR products were subjected to high-resolution melt (HRM) analysis, a new technology that allows precise melt profile determination of amplicons. This investigation shows that the CRISPR HRM assay provides a powerful addition to existing C. jejuni genotyping methods and emphasizes

Erin P. Price; Helen Smith; Flavia Huygens; Philip M. Giffard

2007-01-01

339

Barriers for recess physical activity: a gender specific qualitative focus group exploration  

PubMed Central

Background Many children, in particular girls, do not reach the recommended amount of daily physical activity. School recess provides an opportunity for both boys and girls to be physically active, but barriers to recess physical activity are not well understood. This study explores gender differences in children’s perceptions of barriers to recess physical activity. Based on the socio-ecological model four types of environmental barriers were distinguished: natural, social, physical and organizational environment. Methods Data were collected through 17 focus groups (at 17 different schools) with in total 111 children (53 boys) from fourth grade, with a mean age of 10.4 years. The focus groups included an open group discussion, go-along group interviews, and a gender segregated post-it note activity. A content analysis of the post-it notes was used to rank the children’s perceived barriers. This was verified by a thematic analysis of transcripts from the open discussions and go-along interviews. Results The most frequently identified barriers for both boys and girls were weather, conflicts, lack of space, lack of play facilities and a newly-found barrier, use of electronic devices. While boys and girls identified the same barriers, there were both inter- and intra-gender differences in the perception of these barriers. Weather was a barrier for all children, apart from the most active boys. Conflicts were perceived as a barrier particularly by those boys who played ballgames. Girls said they would like to have more secluded areas added to the school playground, even in large schoolyards where lack of space was not a barrier. This aligned with girls’ requests for more “hanging-out” facilities, whereas boys primarily wanted activity promoting facilities. Conclusion Based on the results from this study, we recommend promoting recess physical activity through a combination of actions, addressing barriers within the natural, social, physical and organizational environment. PMID:24958158

2014-01-01

340

Localization of a gene responsible for autosomal recessive demyelinating neuropathy with focally folded myelin sheaths to chromosome 11q23 by homozygosity mapping and haplotype sharing  

Microsoft Academic Search

Hereditary motor and sensory neuropathy (HMSN) with focally folded myelin sheaths, or Charcot-Marie-Tooth type 4B (CMT4B), is a distinct clinical entity belonging to the heterogeneous group of autosomal recessive demyelinating neuropathies. We first described a large pedigree with CMT4B, which showed a high consanguinity level and an autosomal recessive pattern of inheritance. Through conventional linkage analysis, we excluded linkage of

Alessandra Bolino; Valeria Brancolini; Francesco Bono; Amalia Bruni; Antonio Gambardella; Giovanni Romeo; Aldo Quattrone; Marcella Devoto

1996-01-01

341

Effects of Si3N4 passivation on the dc and RF characteristics of metamorphic high-electron-mobility transistors depending on the gate-recess structures  

NASA Astrophysics Data System (ADS)

Effects of the Si3N4 passivation on the dc and RF characteristics of a 0.1 µm metamorphic high-electron-mobility transistor (HEMT) are investigated for narrow and wide gate-recess structures. Maximum drain-source saturation current (Idss,max) and maximum extrinsic transconductance (gm,max) are reduced by ~14.8 and ~11.6%, respectively, in the wide gate-recess structure after the passivation; on the other hand, only ~5.7 and ~4.9% reductions are measured from Idss,max and gm,max, respectively, in the narrow gate-recess structure. We examine the passivation-induced degradation by using a modified charge control model assuming the charged surface states on the Si3N4 interface and a comparative study of the hydrodynamic device simulation with the experimental measurement. From the analysis, it is proposed that the difference of degradation in two different gate structures is due to an approximately three times higher charged surface state density of ~4.5 × 1011 cm-2 in the wide gate-recess structure than ~1.6 × 1011 cm-2 in the narrow gate-recess structure. The cut-off frequency (fT) of the wide gate-recess structure also exhibits a greater reduction of ~14.5%, while the fT of the narrow gate-recess structure is reduced by only ~6.6% after the passivation. This is mainly due to the passivation-induced surface states of a higher density in the wide gate-recess structure. A great increase of the gate-to-drain parasitic capacitance in the wide gate-recess structure makes a major contribution to ~13.5% degradation of the maximum frequency of oscillation.

Oh, J. H.; Han, M.; Baek, Y. H.; Moon, S. W.; Rhee, J. K.; Kim, S. D.

2009-02-01

342

The recession's effect on hospital registered nurse employment growth.  

PubMed

Recessions are not uncommon in the United States, but the most recent recession is arguably the most severe economic downturn since the Great Depression of the 1930s. Although recessions result in increases in national unemployment in most sectors of the economy, they have resulted in increases in registered nurse (RN) employment as many non-working married RNs re-enter the workforce when their spouses lose their jobs. Over the past decade, hospital RN employment increased by more than 400,000 with virtually all of this growth associated with the two recessions that occurred during this period. The most recent recession led to an increase in hospital RN employment that was not only unprecedented in size, estimated at nearly 250,000, but was marked by the employment of large numbers of RNs over 50 years of age. While national unemployment rates remain high, hospitals should prepare for an eventual jobs recovery when many RNs are likely to leave the workforce. PMID:21919412

Buerhaus, Peter I; Auerbach, David I

2011-01-01

343

Pricing Options With Curved Boundaries  

Microsoft Academic Search

This paper provides a general valuation method for the European options whose payoff is restricted by curved boundaries contractually set on the underlying asset price process when it follows the geometric Brownian motion. Our result is based on the generalization of the Levy formula on the Brownian motion by T. W. Anderson in sequential analysis. We give the explicit probability

Naoto Kunitomo; Masayuki Ikeda

1992-01-01

344

Exploring the physical controls of regional patterns of flow duration curves - Part 4: A synthesis of empirical analysis, process modeling and catchment classification  

NASA Astrophysics Data System (ADS)

The paper reports on a four-pronged study of the physical controls on regional patterns of the Flow Duration Curve (FDC). This involved a comparative analysis of long-term continuous data from nearly 200 catchments around the US, encompassing a wide range of climates, geology and ecology. The analysis was done from three different perspectives - statistical analysis, process-based modeling, and data-based classification, followed by a synthesis, which is the focus of this paper. Streamflow data was separated into fast and slow flow responses, and associated signatures, and both total flow and its components were analyzed to generate patterns. Regional patterns emerged in all aspects of the study. The mixed gamma distribution described well the shape of the FDC; regression analysis indicated that certain climate and catchment properties were first order controls on the shape of the FDC. In order to understand the spatial patterns revealed by the statistical study, and guided by the hypothesis that the middle portion of the FDC is a function of the regime curve (RC, mean within year variation of flow), we set out to classify these catchments, both empirically and through process-based modeling, in terms of their regime behavior. The classification analysis showed that climate seasonality and aridity, either directly (empirical classes) or through phenology (vegetation processes), were the dominant controls on the RC. Quantitative synthesis of these results determined that these classes were indeed related to the FDC through its slope and related statistical parameters. Qualitative synthesis revealed much diversity in the shapes of the FDCs even within each climate-based homogeneous class, especially in the low-flow tails, suggesting that catchment properties may have become the dominant controls. Thus, while the middle portion of the FDC contains the average response of the catchment, and is mainly controlled by climate, the tails of the FDC, notably the low-flow tails, are mainly controlled by catchment properties such as geology and soils. The regime behavior explains only part of the FDC; to gain a deeper understanding of the physical controls on the FDC, these extremes must be analyzed as well. Thus, to completely separate the climate controls from the catchment controls, the roles of catchment properties such as soils, geology, topography etc., must be explored in detail.

Yaeger, M.; Coopersmith, E.; Ye, S.; Cheng, L.; Viglione, A.; Sivapalan, M.

2012-06-01

345

Exploring the physical controls of regional patterns of flow duration curves - Part 4: A synthesis of empirical analysis, process modeling and catchment classification  

NASA Astrophysics Data System (ADS)

The paper reports on a four-pronged study of the physical controls on regional patterns of the flow duration curve (FDC). This involved a comparative analysis of long-term continuous data from nearly 200 catchments around the US, encompassing a wide range of climates, geology, and ecology. The analysis was done from three different perspectives - statistical analysis, process-based modeling, and data-based classification - followed by a synthesis, which is the focus of this paper. Streamflow data were separated into fast and slow flow responses, and associated signatures, and both total flow and its components were analyzed to generate patterns. Regional patterns emerged in all aspects of the study. The mixed gamma distribution described well the shape of the FDC; regression analysis indicated that certain climate and catchment properties were first-order controls on the shape of the FDC. In order to understand the spatial patterns revealed by the statistical study, and guided by the hypothesis that the middle portion of the FDC is a function of the regime curve (RC, mean within-year variation of flow), we set out to classify these catchments, both empirically and through process-based modeling, in terms of their regime behavior. The classification analysis showed that climate seasonality and aridity, either directly (empirical classes) or through phenology (vegetation processes), were the dominant controls on the RC. Quantitative synthesis of these results determined that these classes were indeed related to the FDC through its slope and related statistical parameters. Qualitative synthesis revealed much diversity in the shapes of the FDCs even within each climate-based homogeneous class, especially in the low-flow tails, suggesting that catchment properties may have become the dominant controls. Thus, while the middle portion of the FDC contains the average response of the catchment, and is mainly controlled by climate, the tails of the FDC, notably the low-flow tails, are mainly controlled by catchment properties such as geology and soils. The regime behavior explains only part of the FDC; to gain a deeper understanding of the physical controls on the FDC, these extremes must be analyzed as well. Thus, to completely separate the climate controls from the catchment controls, the roles of catchment properties such as soils, geology, topography etc. must be explored in detail.

Yaeger, M.; Coopersmith, E.; Ye, S.; Cheng, L.; Viglione, A.; Sivapalan, M.

2012-11-01

346

Kilimanjaro Ice Cliffs: morphology, recession, micro-climate, and how they determine glacier area loss  

NASA Astrophysics Data System (ADS)

We present a comprehensive study of the ice cliffs on Kilimanjaro including a morphological description, results from four high-resolution photogrammetrical surveys, a physical analysis of their recession and the micro-climatological drivers behind it, and how the ice cliffs determine glacier area loss on Africa's highest mountain. Since more than one century the near-vertical ice cliffs at the margins of the plateau glaciers on Kilimanjaro (5895m a.s.l., Tanzania, East Africa) have fascinated climbers and explorers but only since about one decade it is known that they determine glacier area loss. They tend to be either facing north or south and continuously recede at a rate of nearly one meter per year. This recession is irreversible because there is no accumulation possible at the cliff faces and ice deformation is very minor. A process-based surface mass balance model, forced by automatic weather station and eddy-covariance data and validated against high resolution photogrammetric surveys, showed that the recession is rather robust against climatic changes. Consequently, as long as the cliffs exist, glacier area on the summit plateau of Kilimanjaro will decrease, and this shrinkage cannot be directly linked to climatic changes! The only way to conserve the Kilimanjaro glaciers is to permanently build up new ice bodies from heavy snowfalls but the frequency of those events has decreased since about 1880. However, in order to decipher climate signals from glacier shrinkage on Kilimanjaro it is key to understand the physical processes at the ice cliffs.

Winkler, M.; Kaser, G.; Moelg, T.; Cullen, N. J.; Pfeffer, T.; Hanke, K.; Wohlfahrt, G.

2011-12-01

347

Identification of CHIP as a Novel Causative Gene for Autosomal Recessive Cerebellar Ataxia  

PubMed Central

Autosomal recessive cerebellar ataxias are a group of neurodegenerative disorders that are characterized by complex clinical and genetic heterogeneity. Although more than 20 disease-causing genes have been identified, many patients are still currently without a molecular diagnosis. In a two-generation autosomal recessive cerebellar ataxia family, we mapped a linkage to a minimal candidate region on chromosome 16p13.3 flanked by single-nucleotide polymorphism markers rs11248850 and rs1218762. By combining the defined linkage region with the whole-exome sequencing results, we identified a homozygous mutation (c.493CT) in CHIP (NM_005861) in this family. Using Sanger sequencing, we also identified two compound heterozygous mutations (c.389AT/c.441GT; c.621C>G/c.707GC) in CHIP gene in two additional kindreds. These mutations co-segregated exactly with the disease in these families and were not observed in 500 control subjects with matched ancestry. CHIP colocalized with NR2A, a subunit of the N-methyl-D-aspartate receptor, in the cerebellum, pons, medulla oblongata, hippocampus and cerebral cortex. Wild-type, but not disease-associated mutant CHIPs promoted the degradation of NR2A, which may underlie the pathogenesis of ataxia. In conclusion, using a combination of whole-exome sequencing and linkage analysis, we identified CHIP, encoding a U-box containing ubiquitin E3 ligase, as a novel causative gene for autosomal recessive cerebellar ataxia. PMID:24312598

Shi, Yuting; Wang, Junling; Li, Jia-Da; Ren, Haigang; Guan, Wenjuan; He, Miao; Yan, Weiqian; Zhou, Ying; Hu, Zhengmao; Zhang, Jianguo; Xiao, Jingjing; Su, Zheng; Dai, Meizhi; Wang, Jun; Jiang, Hong; Guo, Jifeng; Zhou, Yafang; Zhang, Fufeng; Li, Nan; Du, Juan; Xu, Qian; Hu, Yacen; Pan, Qian; Shen, Lu; Wang, Guanghui; Xia, Kun; Zhang, Zhuohua; Tang, Beisha

2013-01-01

348

Strategies for mapping heterogeneous recessive traits by allele-sharing methods.  

PubMed Central

We investigate strategies for detecting linkage of recessive and partially recessive traits, using sibling pairs and inbred individuals. We assume that a genomewide search is being conducted and that locus heterogeneity of the trait is likely. For sibling pairs, we evaluate the efficiency of different statistics under the assumption that one does not know the true degree of recessiveness of the trait. We recommend a sibling-pair statistic that is a linear compromise between two previously suggested statistics. We also compare the power of sibling pairs to that of more distant relatives, such as cousins. For inbred individuals, we evaluate the power of offspring of different types of matings and compare them to sibling pairs. Over a broad range of trait etiologies, sibling pairs are more powerful than inbred individuals, but for traits caused by very rare alleles, particularly in the case of heterogeneity, inbred individuals can be much more powerful. The models we develop can also be used to examine specific situations other than those we look at. We present this analysis in the idealized context of a dense set of highly polymorphic markers. In general, incorporation of real-world complexities makes inbred individuals, particularly offspring of distant relatives, look slightly less useful than our results imply. PMID:9106544

Feingold, E; Siegmund, D O

1997-01-01

349

Distribution of MR-induced sex-linked recessive lethal mutations in Drosophila melanogaster.  

PubMed

In the 'doubling-dose' method currently used in genetic risk evaluation, two principle assumptions are made and these are: (1) there is proportionality between spontaneous and induced mutations and (2) the lesions that lead to spontaneous and induced mutations are essentially similar. The studies reported in this paper were directed at examining the validity of these two assumptions in Drosophila. An analysis was made of the distribution of sex-linked recessive lethals induced by MR, one of the well-studied mutator systems in Drosophila. Appropriate genetic complementation tests with 15 defined X-chromosome duplications showed that MR-induced lethals occurred at many sites along the X-chromosome (in contrast to the known locus specificity of MR-induced visible-mutations); some, but not all these sites at which recessive lethals arose in the MR-system are the same as those known to be hot-spots for X-ray-induced lethals. With in situ hybridization we were able to demonstrate that a majority of MR-induced lethals is associated with a particular mobile DNA sequence, the P-element, i.e. they arose as a result of transposition. The differences between the profiles of MR-induced and X-ray-induced recessive lethals, and the nature of MR-induced and X-ray-induced mutations, thus raise questions about the validity of the assumptions involved in the use of the 'doubling-dose' method. PMID:3923338

Eeken, J C; Sobels, F H; Hyland, V; Schalet, A P

1985-01-01

350

The Great Recession and the Risk for Child Maltreatment  

PubMed Central

This study draws on the Fragile Families and Child Wellbeing Study (N = 2,032), a birth cohort study of families with children from 20 U.S. cities. Interviews occurred between August 2007, and February 2010, when the children were approximately 9 years old. Macro-economic indicators of the Great Recession such as the Consumer Sentiment Index and unemployment and home foreclosure rates were matched to the data to estimate the links between different measures of the Great Recession and high frequency maternal spanking. We find that the large decline in consumer confidence during the Great Recession, as measured by the Consumer Sentiment Index, was associated with worse parenting behavior. In particular, lower levels of consumer confidence were associated with increased levels of high frequency spanking, a parenting behavior that is associated with greater likelihood of being contacted by child protective services. PMID:24045057

Brooks-Gunn, Jeanne; Schneider, William; Waldfogel, Jane

2013-01-01

351

Relating Streamflow Recession to Soil and Watershed Properties  

NASA Astrophysics Data System (ADS)

By exploring the empirical relationship between streamflow recession data from USGS streamgauges and soils data from the Soil Survey Geographic (SSURGO) Database, we test the general hypothesis that a relationship exists between soil properties derived from soil data integrated across a watershed and streamflow recession parameters. This empirical study provides a background for developing a priori parameters with SSURGO soil survey data for parameterizing watersheds for distributed hydrologic modeling and streamflow prediction. Using a random sample of 48 watersheds from across the continental United States, we found a significant correlation between streamflow recession parameters and soil sensitivity, which we define as a combination of hydraulic conductivity, porosity, and soil depth. Our work improves the understanding of streamflow generation processes by exploring how this correlation changes between different geographic regions and climate regimes.

Bandaragoda, C.; Tarboton, D.; Woods, R.; Boettinger, J.

2007-12-01

352

The Great Recession and the risk for child maltreatment.  

PubMed

This study draws on the Fragile Families and Child Wellbeing Study (N=2,032), a birth cohort study of families with children from 20 U.S. cities. Interviews occurred between August 2007, and February 2010, when the children were approximately 9 years old. Macro-economic indicators of the Great Recession such as the Consumer Sentiment Index and unemployment and home foreclosure rates were matched to the data to estimate the links between different measures of the Great Recession and high frequency maternal spanking. We find that the large decline in consumer confidence during the Great Recession, as measured by the Consumer Sentiment Index, was associated with worse parenting behavior. In particular, lower levels of consumer confidence were associated with increased levels of high frequency spanking, a parenting behavior that is associated with greater likelihood of being contacted by child protective services. PMID:24045057

Brooks-Gunn, Jeanne; Schneider, William; Waldfogel, Jane

2013-10-01

353

The Great Recession, somatic symptomatology and alcohol use and abuse.  

PubMed

While most research has examined the long-term effects of alcohol consumption on health, the current study examines how health status impacts on drinking behavior. Using data from a national study conducted between 2010 and 2011 to assess the impact of the recession on drinking behavior, this study examines how economic hardships linked to the recent economic recession affect physical health, and how physical health may in turn affect alcohol use. Structural equation models were used to test the predicted associations. The data demonstrate that many of the economic stressors linked to the recession are associated with increased somatic symptoms. Somatic symptoms are also associated with increased drinking for men, but not for women. These findings suggest that men may use alcohol to self medicate somatic symptomatology. The current findings are consistent with gender role-based explanations that account for gender disparities in the utilization of medical care. PMID:22632797

Vijayasiri, Ganga; Richman, Judith A; Rospenda, Kathleen M

2012-09-01

354

Autosomal Recessive Polycystic Kidney Disease: Antenatal Diagnosis and Histopathological Correlation  

PubMed Central

Autosomal recessive polycystic kidney disease (ARPKD) is one of the most common inheritable disease manifesting in infancy and childhood with a frequency of 1:6,000 to 1:55,000 births. The patient in her second trimester presented with a history of amenorrhea. Ultrasound examination revealed bilateral, enlarged, hyperechogenic kidneys, placentomegaly, and severe oligohydramnios. The pregnancy was terminated. An autopsy was performed on the fetus. Both the kidneys were found to be enlarged and the cut surface showed numerous cysts. The liver sections showed changes due to fibrosis. The final diagnosis of autosomal recessive polycystic kidney disease was made based on these findings. In this article, we correlate the ante-natal ultrasound and histopathological findings in autosomal recessive polycystic kidney disease. PMID:23814685

Rajanna, Dayananda Kumar; Reddy, Anjani; Srinivas, Naren Satya; Aneja, Ankur

2013-01-01

355

Computerised curve deconvolution of TL/OSL curves using a popular spreadsheet program.  

PubMed

This paper exploits the possibility of using commercial software for thermoluminescence and optically stimulated luminescence curve deconvolution analysis. The widely used software package Microsoft Excel, with the Solver utility has been used to perform deconvolution analysis to both experimental and reference glow curves resulted from the GLOw Curve ANalysis INtercomparison project. The simple interface of this programme combined with the powerful Solver utility, allows the analysis of complex stimulated luminescence curves into their components and the evaluation of the associated luminescence parameters. PMID:21765155

Afouxenidis, D; Polymeris, G S; Tsirliganis, N C; Kitis, G

2012-05-01

356

Economic recession and fertility in the developed world.  

PubMed

This article reviews research on the effects of economic recessions on fertility in the developed world. We study how economic downturns, as measured by various indicators, especially by declining GDP levels, falling consumer confidence, and rising unemployment, were found to affect fertility. We also discuss particular mechanisms through which the recession may have influenced fertility behavior, including the effects of economic uncertainty, falling income, changes in the housing market, and rising enrollment in higher education, and also factors that influence fertility indirectly such as declining marriage rates. Most studies find that fertility tends to be pro-cyclical and often rises and declines with the ups and downs of the business cycle. Usually, these aggregate effects are relatively small (typically, a few percentage points) and of short durations; in addition they often influence especially the timing of childbearing and in most cases do not leave an imprint on cohort fertility levels. Therefore, major long-term fertility shifts often continue seemingly uninterrupted during the recession—including the fertility declines before and during the Great Depression of the 1930s and before and during the oil shock crises of the 1970s. Changes in the opportunity costs of childbearing and fertility behavior during economic downturn vary by sex, age, social status, and number of children; childless young adults are usually most affected. Furthermore, various policies and institutions may modify or even reverse the relationship between recessions and fertility. The first evidence pertaining to the recent recession falls in line with these findings. In most countries, the recession has brought a decline in the number of births and fertility rates, often marking a sharp halt to the previous decade of rising fertility rates. PMID:22066128

Sobotka, Tomáš; Skirbekk, Vegard; Philipov, Dimiter

2011-01-01

357

Drinking In the Age of the Great Recession  

PubMed Central

The United States has experienced the most severe economic crisis since the Great Depression. This paper presents an instrument (Life Change Consequences of the Great Recession; LCCGR) depicting work and personal life-related stressors reflecting the enduring effects of the Great Recession. A national sample of 663 respondents completed a mail survey including this instrument and measures of drinking outcomes. Multiple regression analyses addressed the links between the LCCGR and drinking. Economy-related stressors manifested significant effects on both male and female consumptions patterns, but most LCCGR subscales were more clearly related to problematic drinking patterns in males compared to females. PMID:22540437

Richman, Judith A.; Rospenda, Kathleen M.; Johnson, Timothy P.; Cho, Young Ilk; Vijayasira, Ganga; Cloninger, Lea; Wolff, Jennifer M.

2012-01-01

358

Drinking in the age of the Great Recession.  

PubMed

The United States has been experiencing the most severe economic crisis since the Great Depression. This article presents the Life Change Consequences of the Great Recession (LCCGR), an instrument depicting work and personal life-related stressors reflecting the enduring effects of the Great Recession. A national sample of 663 respondents completed a mail survey including this instrument and measures of drinking outcomes. Multiple regression analyses addressed the links between the LCCGR and drinking. Economy-related stressors manifested significant effects on both male and female consumptions patterns, but most LCCGR subscales were more clearly related to problematic drinking patterns in men compared with women. PMID:22540437

Richman, Judith A; Rospenda, Kathleen M; Johnson, Timothy P; Cho, Young Ilk; Vijayasira, Ganga; Cloninger, Lea; Wolff, Jennifer M

2012-01-01

359

The prompt-afterglow connection in gamma-ray bursts: a comprehensive statistical analysis of Swift X-ray light curves  

NASA Astrophysics Data System (ADS)

We present a comprehensive statistical analysis of Swift X-ray light curves of gamma-ray bursts (GRBs) collecting data from more than 650 GRBs discovered by Swift and other facilities. The unprecedented sample size allows us to constrain the rest-frame X-ray properties of GRBs from a statistical perspective, with particular reference to intrinsic time-scales and the energetics of the different light-curve phases in a common rest-frame 0.3-30 keV energy band. Temporal variability episodes are also studied and their properties constrained. Two fundamental questions drive this effort: (i) Does the X-ray emission retain any kind of `memory' of the prompt ?-ray phase? (ii) Where is the dividing line between long and short GRB X-ray properties? We show that short GRBs decay faster, are less luminous and less energetic than long GRBs in the X-rays, but are interestingly characterized by similar intrinsic absorption. We furthermore reveal the existence of a number of statistically significant relations that link the X-ray to prompt ?-ray parameters in long GRBs; short GRBs are outliers of the majority of these two-parameter relations. However and more importantly, we report on the existence of a universal three-parameter scaling that links the X-ray and the ?-ray energy to the prompt spectral peak energy of both long and short GRBs: EX, iso?E1.00 ± 0.06?, iso/E0.60 ± 0.10pk.

Margutti, R.; Zaninoni, E.; Bernardini, M. G.; Chincarini, G.; Pasotti, F.; Guidorzi, C.; Angelini, L.; Burrows, D. N.; Capalbi, M.; Evans, P. A.; Gehrels, N.; Kennea, J.; Mangano, V.; Moretti, A.; Nousek, J.; Osborne, J. P.; Page, K. L.; Perri, M.; Racusin, J.; Romano, P.; Sbarufatti, B.; Stafford, S.; Stamatikos, M.

2013-01-01

360

A mathematical model based on the limit dilution method to obtain linear calibration curves which eliminate the matrix effect in quantitative analysis by X-ray fluorescence  

NASA Astrophysics Data System (ADS)

We propose a mathematical model from an analytical application viewpoint inspired in the limit dilution method. The theoretical development of the model and its results are given. The model shows that there is a linear relation between the inverse of fluorescence intensity and the inverse of the dilution factor; each analytic system (sample, diluent and analyte) is characterised by a general linear function which is easily obtained. The analytical applications arising from this linearity are of great importance in X-ray fluorescence analysis. The following immediate applications are proposed: direct procurement of the total correction factor Y/ H, rapid calculation of the fluorescence intensity of the analyte in a sample ( Iis) and direct calculation of the corrected fluorescence intensity ( IisF). The suggested model makes it possible to deduce a linear function between the fluorescence intensity of the analyte and the analyte concentration in successive dilutions of a standard; this straight line behaves as a calibration curve with direct application in X-ray fluorescence analysis. The proposed model may be applied to complex samples of geological origin, with elimination of the matrix effect. The results obtained in the determination of Ca, K, Fe and Ti in a standard soil show complete agreement with the certified reference values with a relative error about 0.5%, even using a standard shale with very different chemical composition as reference sample.

Bosch Reig, F.; Gimeno Adelantado, J. V.; Peris Martínez, V.; Bosch Mossi, F.

1995-07-01

361

The Curved Cube  

NSDL National Science Digital Library

Take a solid cube with rods attached at diagonally opposite vertices. Hold the rods horizontally and rapidly spin the cube. (See Figure 1.) You should see a curved outline formed by the spinning cube. The objective of this demos is to discover how the straight edges of the cube become curved. The demo is physically based, but can be simulated within various software packages.

Hill, David R.

2003-02-24

362

Anodic Polarization Curves Revisited  

ERIC Educational Resources Information Center

An experiment published in this "Journal" has been revisited and it is found that the curve pattern of the anodic polarization curve for iron repeats itself successively when the potential scan is repeated. It is surprising that this observation has not been reported previously in the literature because it immediately brings into…

Liu, Yue; Drew, Michael G. B.; Liu, Ying; Liu, Lin

2013-01-01

363

Following the Cuts: How Is the Recession Affecting Faculty Work?  

ERIC Educational Resources Information Center

The recession of 2008-2009 and the continuing decline in local, state, and federal funds available to support higher education have resulted in serious budget cuts and belt-tightening. Given that faculty constitute an institution's most costly resource, it was not surprising, though it is nonetheless disheartening, to learn of the University of…

Lounder, Andrew; Waugaman, Chelsea; Kenyon, Mark; Levine, Amy; Meekins, Matthew; O'Meara, KerryAnn

2011-01-01

364

3. EXTERIOR OF FRONT ENTRY SHOWING GABLE OVER RECESSED PORCH ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. EXTERIOR OF FRONT ENTRY SHOWING GABLE OVER RECESSED PORCH WITH RUSTIC STYLE DECORATIVE TREATMENT. WELDED STEEL PORCH RAILING ADDED IN 1972 IS VISIBLE AT PHOTO CENTER. VIEW TO SOUTHWEST. - Rush Creek Hydroelectric System, Worker Cottage, Rush Creek, June Lake, Mono County, CA

365

The Effects of Alaska's Economic Recession on Anchorage Households.  

ERIC Educational Resources Information Center

This publication is based on two surveys of the same Anchorage, Alaska households taken in June and November 1987 to study the effects of a strong recession of the previous two years. Different kinds of households were queried about household incomes, housing status, members' occupations, moving plans, and expectations about the financial future.…

Foster, Karen Pyle; And Others

1988-01-01

366

Winter Recess Dining Room Schedule 2012-2013 Lakeshore Area  

E-print Network

, Elizabeth Waters and Four Lakes Market will open at 7AM to allow you to have breakfast before your exams Lakes Market dining venues will open early at 7AM. Final 11.19.12 #12;Winter Recess Dining Room Schedule 2012-2013 Southeast Area * On Sunday, December 16, 2012, Gordon Avenue Market will open at 7AM to allow

Scharer, John E.

367

Spectrum of ABCR gene mutations in autosomal recessive macular dystrophies  

Microsoft Academic Search

Stargardt disease (STGD) and late-onset fundus flavimaculatus (FFM) are autosomal recessive conditions leading to macular degenerations in childhood and adulthood, respectively. Recently, mutations of the photoreceptor cell-specific ATP binding transporter gene (ABCR) have been reported in Stargardt disease. Here, we report on the screening of the whole coding sequence of the ABCR gene in 40 unrelated STGD and 15 FFM

Jean-Michel Rozet; Sylvie Gerber; Eric Souied; Isabelle Perrault; Sophie Châtelin; Imad Ghazi; Corinne Leowski; Jean-Louis Dufier; Arnold Munnich; Josseline Kaplan; J-M Rozet

1998-01-01

368

The Great Recession and College Access Donald E. Heller  

E-print Network

The Great Recession and College Access Donald E. Heller Schreyer Honors College External Advisory education - national Tuition prices are up, family incomes and assets are flat or down While maximum Pell,473) universities No increase in Pell Grants this year State funding for higher education has decreased 1% last

Heller, Don

369

Recession and Recovery Six Fundamental Errors of the Current Orthodoxy  

Microsoft Academic Search

As the recession has deepened and the financial debacle has passed from one flare-up to another during the past year and a half, commentary on the economy's troubles has swelled tremendously. Pundits have pontificated; journalists and editors have reported and opined; talk radio jocks have huffed and puffed; public officials have spewed out even more double-talk than usual; awkward academic

ROBERT HIGGS

2010-01-01

370

Clinical Features: Autosomal recessive primary microcephaly (MCPH) is characterized by  

E-print Network

12/10 Clinical Features: Autosomal recessive primary microcephaly (MCPH) is characterized by: · congenital microcephaly (3 SD below the mean at birth or at least 4 SD below the mean at later ages) · mental weight and appearance except for the microcephaly Brain imaging shows a mildly reduced number of gyri

Gilad, Yoav

371

Clinical Features: Autosomal recessive primary microcephaly (MCPH) is characterized by  

E-print Network

3/10 Clinical Features: Autosomal recessive primary microcephaly (MCPH) is characterized by: · congenital microcephaly (3 SD below the mean at birth or at least 4 SD below the mean at later ages) · mental weight and appearance except for the microcephaly Brain imaging shows a mildly reduced number of gyri

Das, Soma

372

Recession Takes Toll on U.S. Student Aid.  

ERIC Educational Resources Information Center

Insufficient funding for college work-study programs, increased student loan defaults, unanticipated deficits in the federal Pell Grant program, and the climate of recession are creating serious problems for student financial aid. Some fear enrollments will be affected and federal programs will be further reduced. (MSE)

DeLoughry, Thomas J.

1992-01-01

373

Evidence for genetic homogeneity in autosomal recessive generalised myotonia (Becker)  

Microsoft Academic Search

Generalised myotonia Becker (GM) is an autosomal recessively inherited muscle disorder. Affected subjects exhibit myotonic muscle stiffness in all skeletal muscles with marked hypertrophy in the legs. A transient muscle weakness is particularly pronounced in the arms and hands and is a typical symptom of the disorder. Recently, we showed complete linkage of the disorder GM to the gene (CLCN1)

M C Koch; K Ricker; M Otto; F Wolf; B Zoll; C Lorenz; K Steinmeyer; T J Jentsch

1993-01-01

374

Intrinsically Motivated, Free-Time Physical Activity: Considerations for Recess  

ERIC Educational Resources Information Center

The current childhood obesity rates raise concern about youths' health and the role that a sedentary lifestyle plays in this growing trend. Focusing on how children choose to spend their free time is one approach that may yield ideas for reducing childhood obesity. Recess is a regularly occurring "free time" period in elementary schools. It is,…

Stellino, Megan Babkes; Sinclair, Christina D.

2008-01-01

375

Hard Times. The Recession Imperils School Reforms and Teachers' Jobs.  

ERIC Educational Resources Information Center

The current recession in the United States imperils teachers' jobs and school reform. States are prioritizing increased spending in such areas as health care and transportation rather than educational improvement. The article discusses specific educational hard times in several states and counties. (SM)

Harp, Lonnie

1991-01-01

376

RRuurraall SSttuuddiieess PPrrooggrraamm Hunger in Oregon During the Great Recession  

E-print Network

RRuurraall SSttuuddiieess PPrrooggrraamm Hunger in Oregon During the Great Recession Mark Edwards as "hunger")a rate in Oregon was not much different from that for the whole US. The difference between Oregon. In the late 1990s and again in the mid 2000s (2006-2008), Oregon's hunger rate was significantly higher than

Tullos, Desiree

377

Rural Studies Program Hunger in Oregon Since the Great Recession  

E-print Network

Rural Studies Program Hunger in Oregon Since the Great Recession Snehalatha Gantla and Mark Edwards- low-food-security rate (also known as "hunger")a was not much different from that for the entire US-2000s (2006-2008), Oregon's hunger rate was significantly higher than that of the U

Escher, Christine

378

Recess in Elementary Schools: Implications for Children Who Have Disabilities.  

ERIC Educational Resources Information Center

This paper reviews historical aspects of play, issues about recess time, and implications for children who have disabilities. It also describes the need for research to acquire information from stakeholders. Play is pleasurable, enjoyable, intrinsic, and the active base for cognitive, social, motor, and language development in children.…

McClure, Cheryl; Kinnison, Lloyd R.

379

Recession Amnesia and the Prospects for New England's Institutions  

ERIC Educational Resources Information Center

Among the little truly predictable, the author suggests three truths. First is the inevitability of recessions. Second is the belief that, in prosperity, these good times will just keep on rolling. Third is the fall. Bubbles will burst, myths shatter, plans unravel and pain sadly borne unjustly by those who didn't have a hand in the decisions that…

Halfond, Jay A.

2010-01-01

380

Children Most Impacted by the Economic Recession Prepared by the  

E-print Network

will hold. -- President-elect Barack Obama, January 8, 2009 The United States was formally declared to be in an economic recession in late 2008, but the effects of child poverty were seen far earlier in Milwaukee Public levels of income by neighborhood for employed parents and analyzes levels of child poverty among schools

Saldin, Dilano

381

Applications to One Business School Skyrocketed Despite Recession  

ERIC Educational Resources Information Center

In the past two years, the global financial crisis has wreaked havoc on businesses in America and abroad. But the gloom and doom seems to have had the opposite effect on business schools. The reason is that a recession often signals the perfect time for proactive students to sharpen their skill sets, shift their career goals (whether toward a…

Tao, Sharon

2010-01-01

382

The Post-Recession Employment Situation: A Comparative Perspective  

ERIC Educational Resources Information Center

Slow economic growth since the end of the U.S. recession in June of 2009 has not yet translated into increases in employment large enough to meaningfully reduce the rate of unemployment. Because expansionary macroeconomic policy has been pursued on both the fiscal and monetary fronts, it appears at first glance that the hands of government at this…

Couch, Kenneth A.

2012-01-01

383

THE GREAT RECESSION:History, Ideology, Hubris and Nemesis  

Microsoft Academic Search

Many books on the 2008 financial crisis and the current recession focus on the financial sector. Unlike them, this book takes the real economy as the starting point and it situates the downturn within the societal context over the last several decades. Important elements of the story include global manufacturing overcapacity and declining profitability, failure of advanced industrial economies to

Michael Siam-Heng Heng

384

Exterior building details of Building A; east façade: recessed panel ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Exterior building details of Building A; east façade: recessed panel inscribed "1859", historic window opening with concrete sill above door, cement plaster dentil course and cornice, truncated wood beam ends, plaster finished brick wall, granite base; westerly view - San Quentin State Prison, Building 22, Point San Quentin, San Quentin, Marin County, CA

385

Cryptographic protocols on real hyperelliptic curves  

Microsoft Academic Search

We present public-key cryptographic protocols for key exchange, digital signatures, and encryption whose security is based on the presumed in- tractability of solving the principal ideal problem, or equivalently, the distance problem, in the real model of a hyperelliptic curve. Our protocols represent a significant improvement over existing protocols using real hyperelliptic curves. Theoretical analysis and numerical experiments indicate that

M. J. Jacobson; R. Scheidler; A. Stein

2007-01-01

386

Parallel Curves: Getting There and Getting Back  

ERIC Educational Resources Information Center

This note takes up the issue of parallel curves while illustrating the utility of "Mathematica" in computations. This work complements results presented earlier. The presented treatment, considering the more general case of parametric curves, provides an analysis of the appearance of cusp singularities, and emphasizes the utility of symbolic…

Agnew, A. F.; Mathews, J. H.

2006-01-01

387

Comparing large scale CCS deployment potential in the USA and China: a detailed analysis based on country-specific CO2 transport & storage cost curves  

SciTech Connect

The United States and China are the two largest emitters of greenhouse gases in the world and their projected continued growth and reliance on fossil fuels, especially coal, make them strong candidates for CCS. Previous work has revealed that both nations have over 1600 large electric utility and other industrial point CO2 sources as well as very large CO2 storage resources on the order of 2,000 billion metric tons (Gt) of onshore storage capacity. In each case, the vast majority of this capacity is found in deep saline formations. In both the USA and China, candidate storage reservoirs are likely to be accessible by most sources with over 80% of these large industrial CO2 sources having a CO2 storage option within just 80 km. This suggests a strong potential for CCS deployment as a meaningful option to efforts to reduce CO2 emissions from these large, vibrant economies. However, while the USA and China possess many similarities with regards to the potential value that CCS might provide, including the range of costs at which CCS may be available to most large CO2 sources in each nation, there are a number of more subtle differences that may help us to understand the ways in which CCS deployment may differ between these two countries in order for the USA and China to work together - and in step with the rest of the world - to most efficiently reduce greenhouse gas emissions. This paper details the first ever analysis of CCS deployment costs in these two countries based on methodologically comparable CO2 source and sink inventories, economic analysis, geospatial source-sink matching and cost curve modeling. This type of analysis provides a valuable insight into the degree to which early and sustained opportunities for climate change mitigation via commercial-scale CCS are available to the two countries, and could facilitate greater collaboration in areas where those opportunities overlap.

Dahowski, Robert T.; Davidson, Casie L.; Dooley, James J.

2011-04-18

388

JiTT - Fighting Recession: 2009  

NSDL National Science Digital Library

This is a JiTT exercise in which students apply introductory-level macroeconomic analysis to the question of how large the stimulus package put forward to Congress in early 2009 needed to be to close the recessionary gap facing the U.S. economy at that time. In particular, this exercise asks students to bring together the concepts of potential and actual GDP, recessionary gaps, fiscal policy, spending and taxing multipliers, and effects of changes in aggregate spending on employment and output.

Simkins, Scott

389

Multivariate curve resolution applied to in situ X-ray absorption spectroscopy data: an efficient tool for data processing and analysis.  

PubMed

Large datasets containing many spectra commonly associated with in situ or operando experiments call for new data treatment strategies as conventional scan by scan data analysis methods have become a time-consuming bottleneck. Several convenient automated data processing procedures like least square fitting of reference spectra exist but are based on assumptions. Here we present the application of multivariate curve resolution (MCR) as a blind-source separation method to efficiently process a large data set of an in situ X-ray absorption spectroscopy experiment where the sample undergoes a periodic concentration perturbation. MCR was applied to data from a reversible reduction-oxidation reaction of a rhenium promoted cobalt Fischer-Tropsch synthesis catalyst. The MCR algorithm was capable of extracting in a highly automated manner the component spectra with a different kinetic evolution together with their respective concentration profiles without the use of reference spectra. The modulative nature of our experiments allows for averaging of a number of identical periods and hence an increase in the signal to noise ratio (S/N) which is efficiently exploited by MCR. The practical and added value of the approach in extracting information from large and complex datasets, typical for in situ and operando studies, is highlighted. PMID:25086889

Voronov, Alexey; Urakawa, Atsushi; van Beek, Wouter; Tsakoumis, Nikolaos E; Emerich, Hermann; Rønning, Magnus

2014-08-20

390

First far-ultraviolet disk-integrated phase curve analysis of Mimas, Tethys and Dione from the Cassini-UVIS data sets  

NASA Astrophysics Data System (ADS)

We perform an analysis of the photometric properties of the icy saturnian satellites at 180 nm, based on the first far-UV disk-integrated phase curves of Mimas, Tethys and Dione. Their interactions with the environment (the E-ring and the magnetosphere) are investigated, leading to a better understanding of the effects of exogenic processes on the system of Saturn. We find that Tethys and Dione have a leading hemisphere brighter than their trailing hemisphere at far-UV wavelengths, while Mimas exhibits a quite uniform reflectance on its surface. No asymmetry is observed between the saturnian and anti-saturnian hemispheres of those satellites, indicating that exogenic processes are important primarily on the leading and trailing hemispheres. Tethys shows a narrower opposition effect, suggesting a more porous regolith on its surface than on Dione and Mimas. This could be the consequence of more significant bombardment by the E-ring grains at the orbit of Tethys. Dione’s photometric properties reveal a more absorbing surface, which could be explained by a lower amount of E-ring grain bombardment and/or by the deposit of a darkening agent mainly on its trailing side.

Royer, Emilie M.; Hendrix, Amanda R.

2014-11-01

391

Laparoscopic right hemicolectomy with complete mesocolic excision provides acceptable perioperative outcomes but is lengthy -- analysis of learning curves for a novice minimally invasive surgeon  

PubMed Central

Background Associated with reduced trauma, laparoscopic colon surgery is an alternative to open surgery. Furthermore, complete mesocolic excision (CME) has been shown to provide superior nodal yield and offers the prospect of better oncological outcomes. Methods All oncologic laparoscopic right colon resections with CME performed by a single surgeon since the beginning of his surgical practice were retrospectively analyzed for operative duration and perioperative outcomes. Results The study included 81 patients. The average duration of surgery was 220.0 (range 206–233) minutes. The initial durations of about 250 minutes gradually decreased to less than 200 minutes in an inverse linear relationship (y = ?0.58x × 248). The major complication rate was 3.6% ± 4.2% and the average nodal yield was 31.3 ± 4.1. CumulativeSum analysis showed acceptable complication rates and oncological results from the beginning of surgeon’s laparoscopic career. Conclusion Developing laparoscopic skills can provide acceptable outcomes in advanced right hemicolectomy for a surgeon who primarily trained in open colorectal surgery. Operative duration is nearly triple that reported for conventional laparoscopic right hemicolectomy. The slow operative duration learning curve without a plateau reflects complex anatomy and the need for careful dissection around critical structures. Should one wish to adopt this strategy either based on some available evidence of superiority or with intention to participate in research, one has to change the view of right hemicolectomy being a rather simple case to being a complex, lengthy laparoscopic surgery. PMID:25265107

Melich, George; Jeong, Duck Hyoun; Hur, Hyuk; Baik, Seung Hyuk; Faria, Julio; Kim, Nam Kyu; Min, Byung Soh

2014-01-01

392

BEER analysis of Kepler and CoRoT light curves: II. Evidence for emission phase shift due to superrotation in four Kepler hot Jupiters  

E-print Network

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 radii of their parent stars. For all four systems, we find that the beaming-based planetary-mass estimate is larger than the mass estimated from the ellipsoidal amplitude, consistent with previous studies for three of these systems- KOI-13, TrES-2 and Kepler-76. We suggest the apparent discrepancy is due to superrotation, first observed for HD 189733b in the infrared. Superrotation of a tidally-locked hot-Jupiter involves an eastward displacement of the planet hot spot from the substellar point, probably due to winds in the planetary atmosphere, an effect that induces an angle shift of the planet reflection/emission phase modulation. In our analysis this angle shift "leaks" into the beaming modulation, artif...

Faigler, Simchon

2014-01-01

393

A new quantitative real-time reverse transcriptase PCR assay and melting curve analysis for detection and genotyping of Ljungan virus strains.  

PubMed

Ljungan virus (LV), a new member of the Picornaviridae, recently isolated from vole species in both Sweden and the USA, is suspected to be pathogenic for humans as an aetiological agent in myocarditis, diabetes, neurological disease and perinatal disease. This study describes for the first time an RT-PCR assay that can identify and quantify LV infection in various tissue sample types using primers and two different minor-groove-binder probes targeting the 5'-untranslated region of the LV genome. The assay, evaluated using control samples derived from various virus cultures and rodent tissues, allows precise quantification of viral load over six orders of magnitude (10(1) to 10(6) viral copies per assay) for all known strains of LV with high sensitivity and specificity. Furthermore, a melting curve analysis (MCA) was developed using two amplicon-specific hybridisation probes that allows rapid genotyping of different LV strains. These new methods provide useful tools to investigate the putative role of LV as a pathogen in both rodents and humans. PMID:17196265

Donoso Mantke, Oliver; Kallies, René; Niklasson, Bo; Nitsche, Andreas; Niedrig, Matthias

2007-04-01

394

Rapid and specific detection of Salmonella in water samples using real-time PCR and High Resolution Melt (HRM) curve analysis.  

PubMed

A real-time PCR assay combined with a pre-enrichment step for the specific and rapid detection of Salmonella in water samples is described. Following amplification of the invA gene target, High Resolution Melt (HRM) curve analysis was used to discriminate between products formed and to positively identify invA amplification. The real-time PCR assay was evaluated for specificity and sensitivity. The assay displayed 100% specificity for Salmonella and combined with a 16-18 h non-selective pre-enrichment step, the assay proved to be highly sensitive with a detection limit of 1.0 CFU/ml for surface water samples. The detection assay also demonstrated a high intra-run and inter-run repeatability with very little variation in invA amplicon melting temperature. When applied to water samples received routinely by the laboratory, the assay showed the presence of Salmonella in particularly surface water and treated effluent samples. Using the HRM based assay, the time required for Salmonella detection was drastically shortened to less than 24 h compared to several days when using standard culturing methods. This assay provides a useful tool for routine water quality monitoring as well as for quick screening during disease outbreaks. PMID:22170841

van Blerk, G N; Leibach, L; Mabunda, A; Chapman, A; Louw, D

2011-01-01

395

Coupled-Channel Analysis of the D ^1? - d ^3? Complex in NaK; Potential Energy Curves and Spin-Orbit Functions  

NASA Astrophysics Data System (ADS)

Two-colour polarization labeling experiments measuring the D ? X system of NaK have characterised more than 99 % of the potential well of the D 1? state of NaK, the last observed level being located 7 cm-1 below the Na(3p ^2P3/2) + K(4s) atomic asymptote. The vibrational progressions all exhibit irregular intervals, because of strong interactions with the nearby d ^3? state. A comprehensive analysis has now been made of all available data concerning the {D 1?} and {d 3?} states. The potential curves are represented by Morse/Lennard Jones analytical functions, with ab initio constraints on the long-range part of V(R). Morse functions are also used to represent the R-dependent diagonal and off-diagonal spin-orbit terms. Initial values for the spin-orbit coupling matrix elements were extracted from quasi-relativistic ab initio calculations. In total, 29 parameters were required to recalculate 95 % of the 1400 observed term energies to within experimental uncertainty, giving an unweighted standard deviation 0.03 cm-1. A Adohi-Krou et al. J. Mol. Spectrosc. 250 27 (2008) P. Kowalczyk J. Mol. Spectrosc. 136 1 (1989)

Drozdova, Anastasia; Ross, Amanda J.; Stolyarov, Andrey V.; Jastrz?bski, Wlodzimierz; Kowalczyk, Pawe?

2010-06-01

396

An autosomal recessive cerebellar ataxia syndrome with upward gaze palsy, neuropathy, and seizures.  

PubMed

The authors describe three siblings born to consanguineous parents with early onset ataxia, dysarthria, myoclonic, generalized tonic clonic seizures, upward gaze palsy, extensor plantar reflexes, sensory neuropathy, and normal cognition. Direct screening excluded mutations in FRDA, TDP1,and SACS genes and at 8344, 3243, and 8993 positions of mitochondrial DNA. Linkage analysis excluded AOA-1, EPM1, EPM2A, EPM2B, CAMOS, and recessive ataxias linked to chromosome 9q34-9qter. This clinical constellation may represent a distinct form of early onset cerebellar ataxia. PMID:15642921

Straussberg, R; Basel-Vanagaite, L; Kivity, S; Dabby, R; Cirak, S; Nurnberg, P; Voit, T; Mahajnah, M; Inbar, D; Saifi, G M; Lupski, J R; Delague, V; Megarbane, A; Richter, A; Leshinsky, E; Berkovic, S F

2005-01-11

397

The Nuclear Zone of a Leimkuhler Curve.  

ERIC Educational Resources Information Center

Proposes a new definition of the nuclear zone of a Bradford or Leimkuhler curve. The mathematical rationale is outlined, and examples of the application of this technique to citation analysis are given. (15 references) (CLB)

Rousseau, Ronald

1987-01-01

398

Recess Activity and General Health Status among Iranian Elementary Schools' Pupils  

PubMed Central

Background: Regular and daily physical activity during childhood and at school is one of the important part of requirements of normal growth, development and well-being. To achieve physical activity promotion among school child aged population recess as outside of class time efforts is scheduled and allows students to engage in physical and social activities. The purpose of the present study was to assess recess activities as well as status of physical activities among a sample of Iranian students at the primary schools. Methods: This cross-sectional study was performed in four randomly selected schools from a list of 26 elementary schools in March, 2012 in the city of Shahindej, located in North-west of Iran. Participants were 439 (10–12 years) elementary schools’. Physical activity level by self-reporting, mental health using the parent-completed Child Health Questionnaire, and happiness was assessed using a Persian translated version of the Subjective Happiness Scale. Hierarchical logistic regression analysis was applied in two steps using the enter method to analyze data in the SPSS version 17. Results: Backward logistic regression analysis showed that gender of the parent who answered the study questions, father’s education, educational grade of children, BMI, physical function, physical health, health status of the children and family function were significantly related to the children’s physical activity level. Conclusion: Promoting parents’ awareness and schools’ staff about importance of physical activities especially in recess times must be an important part of school and community mental health promotion programs. PMID:24688952

Shaghaghi, Abdolreza; Piri, Massumeh; Allahverdipour, Hamid; Asghari- Jafarabadi, Mohammad

2013-01-01

399

Fine mapping of the recessive genic male-sterile gene (Bnms1) in Brassica napus L.  

PubMed

A recessive genic male sterility (RGMS) system, S45 AB, has been developed from spontaneous mutation in Brassica napus canola variety Oro, and is being used for hybrid cultivar development in China. The male sterility of S45 was controlled by two duplicated recessive genes, named as Bnms1 and Bnms2. In this study, a NIL (near-isogenic line) population from the sib-mating of S45 AB was developed and used for the fine mapping of the Bnms1 gene, in which the recessive allele was homozygous at the second locus. AFLP technology combined with BSA (bulked segregant analysis) was used. From a survey of 2,560 primer combinations (+3/+3 selective bases), seven AFLP markers linked closely to the target gene were identified, of which four were successfully converted to sequence characterized amplified region (SCAR) markers. For further analysis, a population of 1,974 individuals was used to map the Bnms1 gene. On the fine map, Bnms1 gene was flanked by two SCAR markers, SC1 and SC7, with genetic distance of 0.1 cM and 0.3 cM, respectively. SC1 was subsequently mapped on linkage group N7 using doubled-haploid mapping populations derived from the crosses Tapidor x Ningyou7 and DH 821 x DHBao 604, available at IMSORB, UK, and our laboratory, respectively. Linkage of an SSR marker, Na12A02, with the Bnms1 gene further confirmed its location on linkage group N7. Na12A02, 2.6 cM away from Bnms1, was a co-dominant marker. These molecular markers developed from this research will facilitate the marker-assisted selection of male sterile lines and the fine map lays a solid foundation for map-based cloning of the Bnms1 gene. PMID:16804725

Yi, Bin; Chen, Yuning; Lei, Shaolin; Tu, Jinxing; Fu, Tingdong

2006-08-01

400

Are Driving and Overtaking on Right Curves More Dangerous than on Left Curves?  

PubMed Central

It is well known that crashes on horizontal curves are a cause for concern in all countries due to the frequency and severity of crashes at curves compared to road tangents. A recent study of crashes in western Sweden reported a higher rate of crashes in right curves than left curves. To further understand this result, this paper reports the results of novel analyses of the responses of vehicles and drivers during negotiating and overtaking maneuvers on curves for right hand traffic. The overall objectives of the study were to find road parameters for curves that affect vehicle dynamic responses, to analyze these responses during overtaking maneuvers on curves, and to link the results with driver behavior for different curve directions. The studied road features were speed, super-elevation, radius and friction including their interactions, while the analyzed vehicle dynamic factors were lateral acceleration and yaw angular velocity. A simulation program, PC-Crash, has been used to simulate road parameters and vehicle response interaction in curves. Overtaking maneuvers have been simulated for all road feature combinations in a total of 108 runs. Analysis of variances (ANOVA) was performed, using two sided randomized block design, to find differences in vehicle responses for the curve parameters. To study driver response, a field test using an instrumented vehicle and 32 participants was reviewed as it contained longitudinal speed and acceleration data for analysis. The simulation results showed that road features affect overtaking performance in right and left curves differently. Overtaking on right curves was sensitive to radius and the interaction of radius with road condition; while overtaking on left curves was more sensitive to super-elevation. Comparisons of lateral acceleration and yaw angular velocity during these maneuvers showed different vehicle response configurations depending on curve direction and maneuver path. The field test experiments also showed that drivers behave differently depending on the curve direction where both speed and acceleration were higher on right than left curves. The implication of this study is that curve direction should be taken into consideration to a greater extent when designing and redesigning curves. It appears that the driver and the vehicle are influenced by different infrastructure factors depending on the curve direction. In addition, the results suggest that the vehicle dynamics response alone cannot explain the higher crash risk in right curves. Further studies of the links between driver, vehicle, and highway characteristics are needed, such as naturalistic driving studies, to identify the key safety indicators for highway safety. PMID:21050608

Othman, Sarbaz; Thomson, Robert; Lanner, Gunnar

2010-01-01

401

Are driving and overtaking on right curves more dangerous than on left curves?  

PubMed

It is well known that crashes on horizontal curves are a cause for concern in all countries due to the frequency and severity of crashes at curves compared to road tangents. A recent study of crashes in western Sweden reported a higher rate of crashes in right curves than left curves. To further understand this result, this paper reports the results of novel analyses of the responses of vehicles and drivers during negotiating and overtaking maneuvers on curves for right hand traffic. The overall objectives of the study were to find road parameters for curves that affect vehicle dynamic responses, to analyze these responses during overtaking maneuvers on curves, and to link the results with driver behavior for different curve directions. The studied road features were speed, super-elevation, radius and friction including their interactions, while the analyzed vehicle dynamic factors were lateral acceleration and yaw angular velocity. A simulation program, PC-Crash, has been used to simulate road parameters and vehicle response interaction in curves. Overtaking maneuvers have been simulated for all road feature combinations in a total of 108 runs. Analysis of variances (ANOVA) was performed, using two sided randomized block design, to find differences in vehicle responses for the curve parameters. To study driver response, a field test using an instrumented vehicle and 32 participants was reviewed as it contained longitudinal speed and acceleration data for analysis. The simulation results showed that road features affect overtaking performance in right and left curves differently. Overtaking on right curves was sensitive to radius and the interaction of radius with road condition; while overtaking on left curves was more sensitive to super-elevation. Comparisons of lateral acceleration and yaw angular velocity during these maneuvers showed different vehicle response configurations depending on curve direction and maneuver path. The field test experiments also showed that drivers behave differently depending on the curve direction where both speed and acceleration were higher on right than left curves. The implication of this study is that curve direction should be taken into consideration to a greater extent when designing and redesigning curves. It appears that the driver and the vehicle are influenced by different infrastructure factors depending on the curve direction. In addition, the results suggest that the vehicle dynamics response alone cannot explain the higher crash risk in right curves. Further studies of the links between driver, vehicle, and highway characteristics are needed, such as naturalistic driving studies, to identify the key safety indicators for highway safety. PMID:21050608

Othman, Sarbaz; Thomson, Robert; Lannér, Gunnar

2010-01-01

402

Terrestrial Exoplanet Light Curves  

E-print Network

The phase or orbital light curves of extrasolar terrestrial planets in reflected or emitted light will contain information about their atmospheres and surfaces complementary to data obtained by other techniques such as spectrosopy. We show calculated light curves at optical and thermal infrared wavelengths for a variety of Earth-like and Earth-unlike planets. We also show that large satellites of Earth-sized planets are detectable, but may cause aliasing effects if the lightcurve is insufficiently sampled.

Eric Gaidos; Nicholas Moskovitz; Darren M. Williams

2005-11-23

403

Examination of the Relationship Between Plot Scale Soil Properties and Catchment Scale Streamflow Recession Properties  

Microsoft Academic Search

This work explores the empirical relationship between streamflow recession data from USGS stream gauges and high-resolution SSURGO soil data. The exploration of connections between streamflow recession and soil properties tests the general hypothesis that a relationship exists between plot scale soils data integrated across a catchment and catchment scale streamflow recession parameters. A dataset has been assembled using USGS HCDN

C. Bandaragoda; D. Tarboton

2006-01-01

404

A mutation in GJB3 is associated with recessive erythrokeratodermia variabilis (EKV) and leads to  

E-print Network

dominant, although there are reports of sporadic and recessive cases as well (2). Autosomal dominant EKVA mutation in GJB3 is associated with recessive erythrokeratodermia variabilis (EKV) and leads. We report here a homozygote mutation in the connexin 31 gene, found in a family that shows recessive

Avraham, Karen

405

Autosomal Recessive Retinitis Pigmentosa and E150K Mutation in the Opsin Gene*S  

E-print Network

Autosomal Recessive Retinitis Pigmentosa and E150K Mutation in the Opsin Gene*S Received with an autosomal dominant (adRP), autosomal recessive (arRP), or X-linked pattern of inheritance. Although to be associated with autosomal recessive retinitis pigmentosa (arRP). The first reported case of arRP associated

Palczewski, Krzysztof

406

Electrostatic Compensation Restores Trafficking of the Autosomal Recessive Retinitis Pigmentosa E150K Opsin  

E-print Network

Electrostatic Compensation Restores Trafficking of the Autosomal Recessive Retinitis Pigmentosa E manner. The E150K opsin mutant associated with rarely occurring autosomal recessive retinitis pigmentosa of the pathophysiology of autosomal recessive retinitis pigmentosa due to the E150K mutation. Rod photoreceptor cells

Palczewski, Krzysztof

407

Factors Controlling Rates of Bluff Recession at Two Sites on Lake Michigan  

Microsoft Academic Search

Empirical relationships between recession rate of bluffs and precipitation, storm frequency, lake level, deep water wave power, and wave impact height are derived for two Lake Michigan shoreline reaches in Wisconsin. Recession rates are determined from digital orthophotos constructed using historical aerial photographs at least once every decade from the 1940s to present. The recession measurements represent spatial averages of

Elizabeth A. Brown; Chin H. Wu; David M. Mickelson; Tuncer B. Edil

2005-01-01

408

Variables associated with children's physical activity levels during recess: the A-CLASS project  

Microsoft Academic Search

BACKGROUND: School recess provides a daily opportunity for children to engage in physically active behaviours. However, few studies have investigated what factors may influence children's physical activity levels in this context. Such information may be important in the development and implementation of recess interventions. The aim of this study was to investigate the association between a range of recess variables

Nicola D Ridgers; Stuart J Fairclough; Gareth Stratton

2010-01-01

409

Characterization of HgIâ single crystals and detectors by x-ray rocking curve analysis and x-ray reflection topography  

Microsoft Academic Search

An attempt has been made to establish a correlation between the results of x-ray rocking curves and x-ray reflection topographs for vapor grown HgIâ, single crystals. X-ray rocking curves were obtained by double crystal spectroscopy with Si as the first crystal and topographs were produced using the Berg-Barrett technique with an asymmetrically cut Si-disperser. The crystals were evaluated at different

R. Ostrom; L. Keller; N. J. Wagner; M. M. Schieber; C. Ortale; L. van den Berg; W. F. Schnepple

1987-01-01

410

The Great Recession, Public Transfers, and Material Hardship  

PubMed Central

Economic downturns lead to lost income and increased poverty. Although high unemployment almost certainly also increases material hardship, and government transfers likely decrease hardship, the first relationship has not yet been documented and the second is poorly understood. We use data from five waves of the Fragile Families and Child Well-being Study to study the relationships between unemployment, government transfers, and material hardship. The latest wave of data was collected during the Great Recession, the worst recession since the Great Depression, providing a unique opportunity to look at how high unemployment rates affect the well-being of low income families. We find that the unemployment rate is associated with increased overall material hardship, difficulty paying bills, having utilities disconnected, and with increased usage of TANF, SNAP, UI and Medicaid. If not for SNAP, food hardship might have increased by twice the amount actually observed. PMID:24379487

Pilkauskas, Natasha V.; Currie, Janet; Garfinkel, Irwin

2013-01-01

411

Mutations of ESPN cause autosomal recessive deafness and vestibular dysfunction.  

PubMed

We mapped a human deafness locus DFNB36 to chromosome 1p36.3 in two consanguineous families segregating recessively inherited deafness and vestibular areflexia. This phenotype co-segregates with either of two frameshift mutations, 1988delAGAG and 2469delGTCA, in ESPN, which encodes a calcium-insensitive actin-bundling protein called espin. A recessive mutation of ESPN is known to cause hearing loss and vestibular dysfunction in the jerker mouse. Our results establish espin as an essential protein for hearing and vestibular function in humans. The abnormal vestibular phenotype associated with ESPN mutations will be a useful clinical marker for refining the differential diagnosis of non-syndromic deafness. PMID:15286153

Naz, S; Griffith, A J; Riazuddin, S; Hampton, L L; Battey, J F; Khan, S N; Riazuddin, S; Wilcox, E R; Friedman, T B

2004-08-01

412

Job Loss and Infrastructure Job Creation During the Recession  

Microsoft Academic Search

[Excerpt] After the long economic expansion that characterized much of the current decade, the nation entered its eleventh postwar recession in December 2007. The unemployment rate rose from 5.0% in that month to 6.7% in November 2008, the latest data released to date by the U.S. Bureau of Labor Statistics (BLS). A majority of those unemployed in November—some 6 out

Linda Levine

2008-01-01

413

Genetic heterogeneity for autosomal recessive pyridoxine-dependent seizures  

Microsoft Academic Search

Pyridoxine-dependent seizure (PDS) is a rare autosomal recessive intractable seizure disorder only controlled by a daily supplementation\\u000a of pharmacological doses of pyridoxine (Vitamin B6). Although glutamate decarboxylase utilizes pyridoxal phosphate as a cofactor\\u000a during conversion of the excitatory amino acid, glutamate, to the inhibitory neurotransmitter, ?-amino butyric acid (GABA),\\u000a several studies have failed to demonstrate a linkage to either of

C. L. Bennett; H. M. Huynh; P. F. Chance; I. A. Glass; S. M. Gospe

2005-01-01

414

4H-SiC PIN Recessed Window Avalanche Photodiode  

Microsoft Academic Search

We report 4H-SiC p-i-n recessed window avalanche photodiodes with low dark current and high quantum efficiency. For a circular device of 250 mum diameter, the device demonstrated a responsivity of ~135.5 mW\\/A (external quantum efficiency = ~64%), a dark current ~90 pA (~0.183 mum\\/cm2) at a photocurrent gain of 1000, and an excess noise factor k of slightly less than

Han-Din Liu; Dion McIntosh; Xiaogang Bai; Huapu Pan; Mingguo Liu; Joe C. Campbell

2007-01-01

415

Massachusetts dental establishments in 2011: after the last recession.  

PubMed

Census Bureau reports for 2007 and 2011 (before and after the last recession) were used to develop data for "average" dental establishments in the counties of Massachusetts. Any changes should be considered while bearing in mind the American Dental Association (ADA) 2013 report indicating that spending for dental services has stagnated. In terms of these findings, the need for continued monitoring of dental establishment activities beyond the confines of one's own facility is emphasized. PMID:24428029

Waldman, H Barry; Perlman, Steven P

2013-01-01

416

Operating temperatures of recessed fluorescent fixtures with thermal insulation  

SciTech Connect

Tests were performed to determine steady state surface temperatures for recessed fluorescent fixtures operated with and without thermal insulation on the top side of the fixture and to identify potential problems associated with the installation of thermal insulation. In addition to measuring temperatures, means were sought by which the fixtures can be thermally insulated and operated without fire hazards or damage to the fixture. (MCW)

Yarbrough, D.W.; Toor, I.A.

1981-05-01

417

Endoscopic Repair of Lateral Sphenoid Recess Cerebrospinal Fluid Leaks  

Microsoft Academic Search

Endoscopic repair of anterior cranial base has been widely reported. However there is still no uniformity in the technique\\u000a of endoscopic repair of lateral sphenoid cerebrospinal fluid (CSF) leaks. To highlight the management of CSF leak or encephalocele\\u000a in the lateral sphenoid recess and relate our experiences. We retrospectively reviewed the medical records of all our patients\\u000a who underwent an

Milind V. Kirtane; Abhineet Lall; Kashmira Chavan; Dhruv Satwalekar

418

Bone Marrow Transplantation for Recessive Dystrophic Epidermolysis Bullosa  

PubMed Central

Background Recessive dystrophic epidermolysis bullosa is an incurable, often fatal mucocutaneous blistering disease caused by mutations in COL7A1, the gene encoding type VII collagen (C7). On the basis of preclinical data showing biochemical correction and prolonged survival in col7?/? mice, we hypothesized that allogeneic marrow contains stem cells capable of ameliorating the manifestations of recessive dystrophic epidermolysis bullosa in humans. Methods Between October 2007 and August 2009, we treated seven children who had recessive dystrophic epidermolysis bullosa with immunomyeloablative chemotherapy and allogeneic stem-cell transplantation. We assessed C7 expression by means of immunofluorescence staining and used transmission electron microscopy to visualize anchoring fibrils. We measured chimerism by means of competitive polymerase-chain-reaction assay, and documented blister formation and wound healing with the use of digital photography. Results One patient died of cardiomyopathy before transplantation. Of the remaining six patients, one had severe regimen-related cutaneous toxicity, with all having improved wound healing and a reduction in blister formation between 30 and 130 days after transplantation. We observed increased C7 deposition at the dermal–epidermal junction in five of the six recipients, albeit without normalization of anchoring fibrils. Five recipients were alive 130 to 799 days after transplantation; one died at 183 days as a consequence of graft rejection and infection. The six recipients had substantial proportions of donor cells in the skin, and none had detectable anti-C7 antibodies. Conclusions Increased C7 deposition and a sustained presence of donor cells were found in the skin of children with recessive dystrophic epidermolysis bullosa after allogeneic bone marrow transplantation. Further studies are needed to assess the long-term risks and benefits of such therapy in patients with this disorder. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT00478244.) PMID:20818854

Wagner, John E.; Ishida-Yamamoto, Akemi; McGrath, John A.; Hordinsky, Maria; Keene, Douglas R.; Riddle, Megan J.; Osborn, Mark J.; Lund, Troy; Dolan, Michelle; Blazar, Bruce R.; Tolar, Jakub

2010-01-01

419

Direct Detection of Macrolide Resistance in Mycoplasma genitalium Isolates from Clinical Specimens from France by Use of Real-Time PCR and Melting Curve Analysis  

PubMed Central

Mycoplasma genitalium is a sexually transmitted organism commonly treated with azithromycin. However, macrolide resistance has been reported and is associated with point mutations in the 23S rRNA gene. To evaluate the prevalence of macrolide resistance in M. genitalium isolates from clinical specimens from France, we first used a previously reported high-resolution melting assay. Because susceptible and resistant M. genitalium isolates were hardly discriminated in M. genitalium-positive clinical specimens, we developed a new molecular assay for the rapid detection of macrolide resistance. An assay using real-time PCR based on fluorescence resonance energy transfer (FRET) coupled with melting curve analysis was designed. The assay was first validated on characterized macrolide-resistant M. genitalium isolates and then applied to 202 urogenital M. genitalium-positive specimens collected from 178 patients from France in 2011 and 2012. Resistant genotypes were confirmed by 23S rRNA gene sequencing. Among the 202 M. genitalium-positive specimens, 155 were amplified, demonstrating a sensitivity of 76.7%. A substitution in the 23S rRNA gene was found in 14.2% of the patient samples. Nine and six patients had M. genitalium isolates with a substitution at positions 2059 and 2058, respectively. In four cases, a mixed population of wild-type and mutated M. genitalium isolates was observed. The prevalence of M. genitalium macrolide resistance has been stable in France since its detection in 2006. Our FRET PCR assay is able to discriminate between wild-type and resistant genotypes directly from clinical specimens. This assay will allow clinicians to shorten the time to the initiation of effective disease treatment. PMID:24574291

Touati, Arabella; Peuchant, Olivia; Jensen, Jorgen S.; Bebear, Cecile

2014-01-01

420

Rapid Detection of K-ras Mutations in Bile by Peptide Nucleic Acid-Mediated PCR Clamping and Melting Curve Analysis: Comparison with Restriction Fragment Length Polymorphism Analysis  

Microsoft Academic Search

Background: Current methods for detection of K-ras gene mutations are time-consuming. We aimed to de- velop a one-step PCR technique using fluorescent hy- bridization probes and competing peptide nucleic acid oligomers to detect K-ras mutations in bile and to compare the efficacy with restriction fragment length polymorphism (RFLP) analysis. Methods: Bile samples were obtained from 116 patients with biliary obstruction,

Chiung-Yu Chen; Shu-Chu Shiesh; Sheu-Jen Wu

421

Autosomal recessive disorders among Arabs: an overview from Kuwait.  

PubMed Central

Kuwait has a cosmopolitan population of 1.7 million, mostly Arabs. This population is a mosaic of large and small minorities representing most Arab communities. In general, Kuwait's population is characterized by a rapid rate of growth, large family size, high rates of consanguineous marriages within the Arab communities with low frequency of intermarriage between them, and the presence of genetic isolates and semi-isolates in some extended families and Bedouin tribes. Genetic services have been available in Kuwait for over a decade. During this time it has become clear that Arabs have a high frequency of genetic disorders, and in particular autosomal recessive traits. Their pattern is unique and some disorders are relatively common. Examples are Bardet-Biedl and Meckel syndromes, phenylketonuria, and familial Mediterranean fever. A relatively large number of new syndromes and variants have been delineated in Kuwait's population, many being the result of homozygosity for autosomal recessive genes that occurred because of inbreeding. Some of these syndromes have subsequently been found in other parts of the world, negating the concept of the private syndrome. This paper provides an overview of autosomal recessive disorders among the Arabs in Kuwait from a personal perspective and published studies, and highlights the need for genetic services in Arab countries with the goal of prevention and treatment of genetic disorders. PMID:8014972

Teebi, A S

1994-01-01

422

Mutations in CERS3 Cause Autosomal Recessive Congenital Ichthyosis in Humans  

PubMed Central

Autosomal recessive congenital ichthyosis (ARCI) is a rare genetic disorder of the skin characterized by abnormal desquamation over the whole body. In this study we report four patients from three consanguineous Tunisian families with skin, eye, heart, and skeletal anomalies, who harbor a homozygous contiguous gene deletion syndrome on chromosome 15q26.3. Genome-wide SNP-genotyping revealed a homozygous region in all affected individuals, including the same microdeletion that partially affects two coding genes (ADAMTS17, CERS3) and abolishes a sequence for a long non-coding RNA (FLJ42289). Whereas mutations in ADAMTS17 have recently been identified in autosomal recessive Weill-Marchesani-like syndrome in humans and dogs presenting with ophthalmologic, cardiac, and skeletal abnormalities, no disease associations have been described for CERS3 (ceramide synthase 3) and FLJ42289 so far. However, analysis of additional patients with non-syndromic ARCI revealed a splice site mutation in CERS3 indicating that a defect in ceramide synthesis is causative for the present skin phenotype of our patients. Functional analysis of patient skin and in vitro differentiated keratinocytes demonstrated that mutations in CERS3 lead to a disturbed sphingolipid profile with reduced levels of epidermis-specific very long-chain ceramides that interferes with epidermal differentiation. Taken together, these data present a novel pathway involved in ARCI development and, moreover, provide the first evidence that CERS3 plays an essential role in human sphingolipid metabolism for the maintenance of epidermal lipid homeostasis. PMID:23754960

Marrakchi, Slaheddine; Ribierre, Florence; Kamoun, Bourane; Abid, Leila; Leipoldt, Michael; Turki, Hamida; Schempp, Werner; Heilig, Roland; Lathrop, Mark; Fischer, Judith

2013-01-01

423

Mutations in CERS3 cause autosomal recessive congenital ichthyosis in humans.  

PubMed

Autosomal recessive congenital ichthyosis (ARCI) is a rare genetic disorder of the skin characterized by abnormal desquamation over the whole body. In this study we report four patients from three consanguineous Tunisian families with skin, eye, heart, and skeletal anomalies, who harbor a homozygous contiguous gene deletion syndrome on chromosome 15q26.3. Genome-wide SNP-genotyping revealed a homozygous region in all affected individuals, including the same microdeletion that partially affects two coding genes (ADAMTS17, CERS3) and abolishes a sequence for a long non-coding RNA (FLJ42289). Whereas mutations in ADAMTS17 have recently been identified in autosomal recessive Weill-Marchesani-like syndrome in humans and dogs presenting with ophthalmologic, cardiac, and skeletal abnormalities, no disease associations have been described for CERS3 (ceramide synthase 3) and FLJ42289 so far. However, analysis of additional patients with non-syndromic ARCI revealed a splice site mutation in CERS3 indicating that a defect in ceramide synthesis is causative for the present skin phenotype of our patients. Functional analysis of patient skin and in vitro differentiated keratinocytes demonstrated that mutations in CERS3 lead to a disturbed sphingolipid profile with reduced levels of epidermis-specific very long-chain ceramides that interferes with epidermal differentiation. Taken together, these data present a novel pathway involved in ARCI development and, moreover, provide the first evidence that CERS3 plays an essential role in human sphingolipid metabolism for the maintenance of epidermal lipid homeostasis. PMID:23754960

Radner, Franz P W; Marrakchi, Slaheddine; Kirchmeier, Peter; Kim, Gwang-Jin; Ribierre, Florence; Kamoun, Bourane; Abid, Leila; Leipoldt, Michael; Turki, Hamida; Schempp, Werner; Heilig, Roland; Lathrop, Mark; Fischer, Judith

2013-06-01

424

Exploring Area between Curves  

NSDL National Science Digital Library

Calculus texts have problems on finding the Areas between Curves in the chapters on applications of Integration. The NCB suggests finding some of these examples in a text and trying them in Harumi's graph. Experimenting on a computer with the approximation for finding the area using rectangles is fascinating. As the number of rectangles increases, the approximation improves. Therefore, mathematicians define the area A between the two curves as the limit of the sum of the areas of these approximating rectangles where n is the number of rectangles bounded between a and b.

Monroy, Harumi

2006-01-01

425

Mixtures of Receiver Operating Characteristic Curves  

PubMed Central

Rationale and Objectives ROC curves are ubiquitous in the analysis of imaging metrics as markers of both diagnosis and prognosis. While empirical estimation of ROC curves remains the most popular method, there are several reasons to consider smooth estimates based on a parametric model. Materials and Methods A mixture model is considered for modeling the distribution of the marker in the diseased population motivated by the biological observation that there is more heterogeneity in the diseased population than there is in the normal one. It is shown that this model results in an analytically tractable ROC curve which is itself a mixture of ROC curves. Results The use of CK-BB isoenzyme in diagnosis of severe head trauma is used as an example. ROC curves are fit using the direct binormal method, ROCKIT and the Box-Cox transformation as well as the proposed mixture model. The mixture model generates an ROC curve that is much closer to the empirical one than the other methods considered. Conclusions Mixtures of ROC curves can be helpful in fitting smooth ROC curves in datasets where the diseased population has higher variability than can be explained by a single distribution. PMID:23643788

Gonen, Mithat

2014-01-01

426

Analytical solutions for recession analyses of sloping aquifers - applicability on relict rock glaciers in alpine catchments  

NASA Astrophysics Data System (ADS)

Rock glaciers as aquifer systems in alpine catchments may strongly influence the hydrological characteristics of these catchments. Thus, they have a high impact on the ecosystem and potential natural hazards such as for example debris flow. Therefore, knowledge of the hydrodynamic processes, internal structure and properties of these aquifers is important for resource management and risk assessment. The investigation of such aquifers often turns out to be expensive and technically complicated because of their strongly limited accessibility. Analytical solutions of discharge recession provide a quick and easy way to estimate aquifer parameters. However, due to simplifying assumptions the validity of the interpretation is often questionable. In this study we compared results of an analytical solution of discharge recessions with results based on a numerical model. This was done in order to analyse the range of uncertainties and the applicability of the analytical method in alpine catchment areas. The research area is a 0.76 km² large catchment in the Seckauer Tauern Range, Austria. The dominant aquifer in this catchment is a rock glacier, namely the Schöneben Rock Glacier. This relict rock glacier (i.e. containing no permafrost at present) covers an area of 0.11 km² and is drained by one spring at the rock glacier front. The rock glacier consists predominantly of gneissic sediments (mainly coarse-grained, blocky at the surface) and extends from 1720 to 1905 m a.s.l.. Discharge of the rock glacier spring is automatically measured since 2002. Electric conductivity and water temperature is monitored since 2008. An automatic weather station was installed in 2011 in the central part of the catchment. Additionally data of geophysical surveys (refraction seismic and ground penetrating radar) have been used to analyse the base slope and inner structure of the rock glacier. The measured data are incorporated into a numerical model implemented in MODFLOW. The numerical model was then compared to the analytical solution based on the one dimensional Boussinesq equation for unconfined flow in sloping aquifers. Field observations as well as results from the numerical model suggest that the rock glacier has a complex internal structure with zones of low hydraulic conductivity and a high conductive layer on top. The analytical solution attempts to represent this heterogeneous aquifer by an equivalent homogeneous medium. However, as the relative contribution of the different aquifer components varies throughout the recession, the parameter estimates are not easily interpreted in terms of actual aquifer properties. Employing analytical solutions for recession analysis in this type of setting therefore requires a sound understanding of the internal structure and its influence on the flow and storage processes within the rock glacier.

Pauritsch, Marcus; Birk, Steffen; Hergarten, Stefan; Kellerer-Pirklbauer, Andreas; Winkler, Gerfried

2014-05-01

427

Curve Matching, Time Warping, and Light Fields: New Algorithms for Computing Similarity between Curves  

Microsoft Academic Search

The problem of curve matching appears in many application domains, like time series analysis, shape matching, speech recognition, and signature verification, among others. Curve matching has been studied extensively by computational geometers, and many measures of similarity have been examined, among them being the Fr´ echet distance (sometimes referred in folklore as the \\

Alon Efrat; Quanfu Fan; Suresh Venkatasubramanian

2007-01-01

428

Analyzing the health care cost curve: a case study.  

PubMed

This case study uses data from a self-insured employer plan to perform an analysis into the properties of the health care cost curve. The analysis shows that one statistical property of the health care cost curve is that costs rise continuously, not on an annual or monthly basis. Graphical analysis indicates that managed care techniques used to restrain costs can also smooth utilization, producing the continuously growing cost curve observed. The analysis further illustrates that there is no one "cost curve"-analysis must be segmented by population. Finally, the power of predictive models to fit the cost curve varies by population. To the extent that these results generalize to other health plans, this analysis should be used to inform the implementation of strategies to bend the cost curve. Population health management programs and health policy should be based on continuous analysis and adaption rather than implemented as one-off changes. PMID:23672232

Lieberthal, Robert D

2013-10-01

429

Graphing Polar Curves  

ERIC Educational Resources Information Center

Graphing polar curves typically involves a combination of three traditional techniques, all of which can be time-consuming and tedious. However, an alternative method--graphing the polar function on a rectangular plane--simplifies graphing, increases student understanding of the polar coordinate system, and reinforces graphing techniques learned…

Lawes, Jonathan F.

2013-01-01

430

Characteristic Curves of PEMFC  

NSDL National Science Digital Library

This in-class exercise will allow students hands-on experience working with a proton exchange membrane fuel cell, or PEMFC. The class will examine the characteristic curve of one of these fuel cells and measure the voltage and current output of the cell. Step by step instructions are provided for the experiment. This document may be downloaded in PDF file format.

2012-07-11

431

Econophysics Master curve for  

E-print Network

-curve collapse of the price-impact function suggests that fluctuations from the supply- and-demand equilibrium this separately for buying and selling. The transactions are classified as being initiated by a buyer or seller is the liq- uidity and sign( ) is +1 or 1 for buying and selling, respectively. For all four years

432

Extinction curves in AGN  

E-print Network

The presence of the dust in the circumnuclear region strongly affects our view of the nucleus itself. The effect is strong in type 2 objects but weaker effect is likely to be present in type 1 objects as well. In these objects a correction to the observed optical/UV spectrum must be done in order to recover the intrinsic spectrum of a nucleus. The approach based on the extinction curve is convenient for that purpose so significant effort has been recently done in order to determine the extinction curve for the circumnuclear material. It seems clear that the circumn