JR-curves of wide plates and CT25 specimens

International Nuclear Information System (INIS)

Aurich, D.; Wobst, K.; Krafka, H.

1987-01-01

In connection with the problem of the applicability of the characteristic specimen date - i.e. the initiation and stable crack propagation under maximal loads, together with the elastic-plastic material behaviour - to that of actual components, spot-check type beside tests were conducted using wide-plate central crack, central notch (CCT, CNT) and double external crack (DECT) samples. The material in question was an StE 460 steel. A comparison between the determined values shows that the assessed pressure vessel behaviour differs extensively to the values derived from the CCT and CNT specimens. The corresponding results obtained from the CT25 and DECT specimens vary only slightly in the region of interest and correspond to real vessel values. (orig./DG) [de

Resource-based interdependencies in value networks for mobile Internet services

NARCIS (Netherlands)

Montalvo, U.W. de; Kar, E. van de; Maitland, C.

2004-01-01

The advent of new electronic platforms, such as fixed and mobile Internet, is forcing firms from a range of industries to come together in so-called 'value networks' for the provision of innovative services. Firms from different industries have widely varying resources. Our analysis is aimed at

Using the Pareto principle in genome-wide breeding value estimation.

Science.gov (United States)

Yu, Xijiang; Meuwissen, Theo H E

2011-11-01

Genome-wide breeding value (GWEBV) estimation methods can be classified based on the prior distribution assumptions of marker effects. Genome-wide BLUP methods assume a normal prior distribution for all markers with a constant variance, and are computationally fast. In Bayesian methods, more flexible prior distributions of SNP effects are applied that allow for very large SNP effects although most are small or even zero, but these prior distributions are often also computationally demanding as they rely on Monte Carlo Markov chain sampling. In this study, we adopted the Pareto principle to weight available marker loci, i.e., we consider that x% of the loci explain (100 - x)% of the total genetic variance. Assuming this principle, it is also possible to define the variances of the prior distribution of the 'big' and 'small' SNP. The relatively few large SNP explain a large proportion of the genetic variance and the majority of the SNP show small effects and explain a minor proportion of the genetic variance. We name this method MixP, where the prior distribution is a mixture of two normal distributions, i.e. one with a big variance and one with a small variance. Simulation results, using a real Norwegian Red cattle pedigree, show that MixP is at least as accurate as the other methods in all studied cases. This method also reduces the hyper-parameters of the prior distribution from 2 (proportion and variance of SNP with big effects) to 1 (proportion of SNP with big effects), assuming the overall genetic variance is known. The mixture of normal distribution prior made it possible to solve the equations iteratively, which greatly reduced computation loads by two orders of magnitude. In the era of marker density reaching million(s) and whole-genome sequence data, MixP provides a computationally feasible Bayesian method of analysis.

Sniffing out significant "Pee values": genome wide association study of asparagus anosmia.

Science.gov (United States)

Markt, Sarah C; Nuttall, Elizabeth; Turman, Constance; Sinnott, Jennifer; Rimm, Eric B; Ecsedy, Ethan; Unger, Robert H; Fall, Katja; Finn, Stephen; Jensen, Majken K; Rider, Jennifer R; Kraft, Peter; Mucci, Lorelei A

2016-12-13

 To determine the inherited factors associated with the ability to smell asparagus metabolites in urine.  Genome wide association study.  Nurses' Health Study and Health Professionals Follow-up Study cohorts.  6909 men and women of European-American descent with available genetic data from genome wide association studies.  Participants were characterized as asparagus smellers if they strongly agreed with the prompt "after eating asparagus, you notice a strong characteristic odor in your urine," and anosmic if otherwise. We calculated per-allele estimates of asparagus anosmia for about nine million single nucleotide polymorphisms using logistic regression. P values asparagus anosmia, all in a region on chromosome 1 (1q44: 248139851-248595299) containing multiple genes in the olfactory receptor 2 (OR2) family. Conditional analyses revealed three independent markers associated with asparagus anosmia: rs13373863, rs71538191, and rs6689553.  A large proportion of people have asparagus anosmia. Genetic variation near multiple olfactory receptor genes is associated with the ability of an individual to smell the metabolites of asparagus in urine. Future replication studies are necessary before considering targeted therapies to help anosmic people discover what they are missing. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Value and limitation of digital subtraction angiography for assessment of myocardial perfusion with varying coronary stenosis

International Nuclear Information System (INIS)

Ohtani, Nozomu

1988-01-01

We examined the value of digital subtraction angiography (DSA) for the assessment of regional myocardial perfusion by comparing with regional myocardial function in 10 anesthetized dogs. With varying degrees of reduction in left circumflex coronary artery (LCX) blood flow (CBF:categories of stenosis (S1-S5)), myocardial perfusion was assessed by injecting the contrast medium(1ml by power injector) selectively into LCX, and the regional myocardium with contrast was imaged with DSA. We recorded aortic pressure (AOP) and systolic wall thickening (%WTh: sonomicrometry) in the left ventricular posterior wall simultaneously with cine pulse. On the time-density curve obtained from the myocardial regin of interest, we calculated a time interval from the contrast injection to peak concentration (TPC) and exponential washout rate (T). Under varying LCX stenosis, there were no significant change of heart rate and mean AOP and a significant linear correlations were found between %WTh and both 1/TPC(r=0.51)and 1/T(r=0.55). At S1(CBF:100-90% of control), neither %WTh nor 1/TPC differed from control, but 1/T was significantly decreased (80% of contral p<0.01). At S3(CRF:79-60%) to S5(CBF:39-0%), all%WTh, 1/TPC and 1/T were significantly decreased from control (all p<0.01), however, at S5(CBF:39-0%) the value of 1/TPC(71% of control) and 1/T(33%) were not different from that at S4, whereas %WTh was markedly reduced and took place to systolic thinning.. Therefore, in critical coronary stenosis, 1/T was more sensitive than 1/TPC or wall dynamics for assessing myocardial perfusion, however, these indices from DSA had a considerable limitation for evaluating the severity of myocardial ischemia when CBF was markedly reduced. (author)

Ethics education for health professionals: a values based approach.

Science.gov (United States)

Godbold, Rosemary; Lees, Amanda

2013-11-01

It is now widely accepted that ethics is an essential part of educating health professionals. Despite a clear mandate to educators, there are differing approaches, in particular, how and where ethics is positioned in training programmes, underpinning philosophies and optimal modes of assessment. This paper explores varying practices and argues for a values based approach to ethics education. It then explores the possibility of using a web-based technology, the Values Exchange, to facilitate a values based approach. It uses the findings of a small scale study to signal the potential of the Values Exchange for engaging, meaningful and applied ethics education. Copyright © 2013 Elsevier Ltd. All rights reserved.

A Reconfigurable Series Resonant DC-DC Converter for Wide-Input and Wide-Output Voltages

DEFF Research Database (Denmark)

Shen, Yanfeng; Wang, Huai; Qin, Zian

2017-01-01

This paper proposes a dual-bridge based LC series resonant dc-dc converter. The input inverter unit incorporates two bridge structures, i.e., a full-bridge inverter and a half-bridge inverter. For the output rectifier, it can be a full-bridge rectifier or an asymmetric half-bridge rectifier....... Different from the conventional resonant converter, a fixed-frequency PWM control is employed which makes the optimization of magnetic components easier. The primary-side switches can achieve ZVS and the secondary-side diodes turn off with ZCS. In addition, the root-mean-square (RMS) values...... of the transformer currents do not significantly vary with respect to the voltage variation. Therefore, this converter can maintain high efficiency over a wide voltage range. The topology and operating principle are firstly described. Then the dc voltage gain and the RMS current characteristics are detailed. Finally...

Genome-wide transcriptome analysis of soybean primary root under varying water-deficit conditions.

Science.gov (United States)

Song, Li; Prince, Silvas; Valliyodan, Babu; Joshi, Trupti; Maldonado dos Santos, Joao V; Wang, Jiaojiao; Lin, Li; Wan, Jinrong; Wang, Yongqin; Xu, Dong; Nguyen, Henry T

2016-01-15

Soybean is a major crop that provides an important source of protein and oil to humans and animals, but its production can be dramatically decreased by the occurrence of drought stress. Soybeans can survive drought stress if there is a robust and deep root system at the early vegetative growth stage. However, little is known about the genome-wide molecular mechanisms contributing to soybean root system architecture. This study was performed to gain knowledge on transcriptome changes and related molecular mechanisms contributing to soybean root development under water limited conditions. The soybean Williams 82 genotype was subjected to very mild stress (VMS), mild stress (MS) and severe stress (SS) conditions, as well as recovery from the severe stress after re-watering (SR). In total, 6,609 genes in the roots showed differential expression patterns in response to different water-deficit stress levels. Genes involved in hormone (Auxin/Ethylene), carbohydrate, and cell wall-related metabolism (XTH/lipid/flavonoids/lignin) pathways were differentially regulated in the soybean root system. Several transcription factors (TFs) regulating root growth and responses under varying water-deficit conditions were identified and the expression patterns of six TFs were found to be common across the stress levels. Further analysis on the whole plant level led to the finding of tissue-specific or water-deficit levels specific regulation of transcription factors. Analysis of the over-represented motif of different gene groups revealed several new cis-elements associated with different levels of water deficit. The expression patterns of 18 genes were confirmed byquantitative reverse transcription polymerase chain reaction method and demonstrated the accuracy and effectiveness of RNA-Seq. The primary root specific transcriptome in soybean can enable a better understanding of the root response to water deficit conditions. The genes detected in root tissues that were associated with

Surface and canopy fuels vary widely in 24-yr old postfire lodgepole pine forests

Science.gov (United States)

Nelson, K. N.; Turner, M.; Romme, W. H.; Tinker, D. B.

2013-12-01

Extreme fire seasons have become common in western North America, and the extent of young postfire forests has grown as fire frequency and annual area burned have increased. These young forests will set the stage for future fires, but an assessment of fuel loads in young forests is lacking. The rate of fuel re-accumulation and fuels variability in postfire forest landscapes is needed to anticipate future fire occurrence and behavior in the American West. We studied fuel characteristics in young lodgepole pine forests that regenerated after the 1988 fires in Yellowstone National Park to address two questions: (1) How do surface fuel characteristics change with time-since-fire? (2) How do canopy and surface fuels vary across the Yellowstone landscape 24 years postfire? During summer 2012, we re-measured surface fuels in 11 plots that were established in 1996 (8 yrs post fire), and we measured surface and canopy fuels in 82 stands (each 0.25 ha) distributed across the Yellowstone post-1988 fire landscape. In the remeasured plots, surface fuel loads generally increased over the last 16 years. One-hr fuels did not change between sample dates, but all other fuel classes (i.e., 10-hr, 100-hr, and 1000-hr) increased by a factor of two or three. Within the sample timeframe, variability of fuel loads within stands decreased significantly. The coefficients of variation decreased for all fuel classes by 23% to 67%. Data from the 82 plots revealed that canopy and surface fuels in 24-year-old stands varied tremendously across the Yellowstone landscape. Live tree densities spanned 0 to 344,067 trees ha-1, producing a mean available canopy fuel load of 7.7 Mg ha-1 and a wide range from 0 to 47 Mg ha-1. Total surface fuel loads averaged 130 Mg ha-1 and ranged from 49 to 229 Mg ha-1, of which 90% was in the 1000-hr fuel class. The mass of fine surface fuels (i.e., litter/duff, 1-hr, 10-hr, and herbaceous fuels) and canopy fuels (i.e., foliage and 1-hr branches) were strongly and

Power System Event Ranking Using a New Linear Parameter-Varying Modeling with a Wide Area Measurement System-Based Approach

Directory of Open Access Journals (Sweden)

Mohammad Bagher Abolhasani Jabali

2017-07-01

Full Text Available Detecting critical power system events for Dynamic Security Assessment (DSA is required for reliability improvement. The approach proposed in this paper investigates the effects of events on dynamic behavior during nonlinear system response while common approaches use steady-state conditions after events. This paper presents some new and enhanced indices for event ranking based on time-domain simulation and polytopic linear parameter-varying (LPV modeling of a power system. In the proposed approach, a polytopic LPV representation is generated via linearization about some points of the nonlinear dynamic behavior of power system using wide-area measurement system (WAMS concepts and then event ranking is done based on the frequency response of the system models on the vertices. Therefore, the nonlinear behaviors of the system in the time of fault occurrence are considered for events ranking. The proposed algorithm is applied to a power system using nonlinear simulation. The comparison of the results especially in different fault conditions shows the advantages of the proposed approach and indices.

H1N1 influenza viruses varying widely in hemagglutinin stability transmit efficiently from swine to swine and to ferrets.

Directory of Open Access Journals (Sweden)

Marion Russier

2017-03-01

Full Text Available A pandemic-capable influenza virus requires a hemagglutinin (HA surface glycoprotein that is immunologically unseen by most people and is capable of supporting replication and transmission in humans. HA stabilization has been linked to 2009 pH1N1 pandemic potential in humans and H5N1 airborne transmissibility in the ferret model. Swine have served as an intermediate host for zoonotic influenza viruses, yet the evolutionary pressure exerted by this host on HA stability was unknown. For over 70 contemporary swine H1 and H3 isolates, we measured HA activation pH to range from pH 5.1 to 5.9 for H1 viruses and pH 5.3 to 5.8 for H3 viruses. Thus, contemporary swine isolates vary widely in HA stability, having values favored by both avian (pH >5.5 and human and ferret (pH ≤5.5 species. Using an early 2009 pandemic H1N1 (pH1N1 virus backbone, we generated three viruses differing by one HA residue that only altered HA stability: WT (pH 5.5, HA1-Y17H (pH 6.0, and HA2-R106K (pH 5.3. All three replicated in pigs and transmitted from pig-to-pig and pig-to-ferret. WT and R106 viruses maintained HA genotype and phenotype after transmission. Y17H (pH 6.0 acquired HA mutations that stabilized the HA protein to pH 5.8 after transmission to pigs and 5.5 after transmission to ferrets. Overall, we found swine support a broad range of HA activation pH for contact transmission and many recent swine H1N1 and H3N2 isolates have stabilized (human-like HA proteins. This constitutes a heightened pandemic risk and underscores the importance of ongoing surveillance and control efforts for swine viruses.

Visualizing time-varying harmonics using filter banks

NARCIS (Netherlands)

Duque, C.A.; Da Silveira, P.M.; Ribeiro, P.F.

2011-01-01

Although it is well known that Fourier analysis is in reality only accurately applicable to steady state waveforms, it is a widely used tool to study and monitor time-varying signals, such as are commonplace in electrical power systems. The disadvantages of Fourier analysis, such as frequency

Ultra wide band antennas

CERN Document Server

Begaud, Xavier

2013-01-01

Ultra Wide Band Technology (UWB) has reached a level of maturity that allows us to offer wireless links with either high or low data rates. These wireless links are frequently associated with a location capability for which ultimate accuracy varies with the inverse of the frequency bandwidth. Using time or frequency domain waveforms, they are currently the subject of international standards facilitating their commercial implementation. Drawing up a complete state of the art, Ultra Wide Band Antennas is aimed at students, engineers and researchers and presents a summary of internationally recog

Analysis of local ionospheric time varying characteristics with singular value decomposition

DEFF Research Database (Denmark)

Jakobsen, Jakob Anders; Knudsen, Per; Jensen, Anna B. O.

2010-01-01

In this paper, a time series from 1999 to 2007 of absolute total electron content (TEC) values has been computed and analyzed using singular value decomposition (SVD). The data set has been computed using a Kalman Filter and is based on dual frequency GPS data from three reference stations in Den...

Comparison of Linear Microinstability Calculations of Varying Input Realism

International Nuclear Information System (INIS)

Rewoldt, G.

2003-01-01

The effect of varying ''input realism'' or varying completeness of the input data for linear microinstability calculations, in particular on the critical value of the ion temperature gradient for the ion temperature gradient mode, is investigated using gyrokinetic and gyrofluid approaches. The calculations show that varying input realism can have a substantial quantitative effect on the results

Comparison of linear microinstability calculations of varying input realism

International Nuclear Information System (INIS)

Rewoldt, G.; Kinsey, J.E.

2004-01-01

The effect of varying 'input realism' or varying completeness of the input data for linear microinstability calculations, in particular on the critical value of the ion temperature gradient for the ion temperature gradient mode, is investigated using gyrokinetic and gyrofluid approaches. The calculations show that varying input realism can have a substantial quantitative effect on the results

The value of electrocardiography for differential diagnosis in wide QRS complex tachycardia.

Science.gov (United States)

Sousa, Pedro A; Pereira, Salomé; Candeias, Rui; de Jesus, Ilídio

2014-03-01

Correct diagnosis in wide QRS complex tachycardia remains a challenge. Differential diagnosis between ventricular and supraventricular tachycardia has important therapeutic and prognostic implications, and although data from clinical history and physical examination may suggest a particular origin, it is the 12-lead surface electrocardiogram that usually enables this differentiation. Since 1978, various electrocardiographic criteria have been proposed for the differential diagnosis of wide complex tachycardias, particularly the presence of atrioventricular dissociation, and the axis, duration and morphology of QRS complexes. Despite the wide variety of criteria, diagnosis is still often difficult, and errors can have serious consequences. To reduce such errors, several differential diagnosis algorithms have been proposed since 1991. However, in a small percentage of wide QRS tachycardias the diagnosis remains uncertain and in these the wisest decision is to treat them as ventricular tachycardias. The authors' objective was to review the main electrocardiographic criteria and differential diagnosis algorithms of wide QRS tachycardia. Copyright © 2012 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Adenoma detection rate varies greatly during colonoscopy training

NARCIS (Netherlands)

van Doorn, Sascha C.; Klanderman, Robert B.; Hazewinkel, Yark; Fockens, Paul; Dekker, Evelien

2015-01-01

The adenoma detection rate (ADR) is considered the most important quality indicator for colonoscopy and varies widely among colonoscopists. It is unknown whether the ADR of gastroenterology consultants can already be predicted during their colonoscopy training. To evaluate the ADR of fellows in

The asymmetry of U.S. monetary policy: Evidence from a threshold Taylor rule with time-varying threshold values

Science.gov (United States)

Zhu, Yanli; Chen, Haiqiang

2017-05-01

In this paper, we revisit the issue whether U.S. monetary policy is asymmetric by estimating a forward-looking threshold Taylor rule with quarterly data from 1955 to 2015. In order to capture the potential heterogeneity for regime shift mechanism under different economic conditions, we modify the threshold model by assuming the threshold value as a latent variable following an autoregressive (AR) dynamic process. We use the unemployment rate as the threshold variable and separate the sample into two periods: expansion periods and recession periods. Our findings support that the U.S. monetary policy operations are asymmetric in these two regimes. More precisely, the monetary authority tends to implement an active Taylor rule with a weaker response to the inflation gap (the deviation of inflation from its target) and a stronger response to the output gap (the deviation of output from its potential level) in recession periods. The threshold value, interpreted as the targeted unemployment rate of monetary authorities, exhibits significant time-varying properties, confirming the conjecture that policy makers may adjust their reference point for the unemployment rate accordingly to reflect their attitude on the health of general economy.

Bounds and asymptotics for orthogonal polynomials for varying weights

CERN Document Server

Levin, Eli

2018-01-01

This book establishes bounds and asymptotics under almost minimal conditions on the varying weights, and applies them to universality limits and entropy integrals.  Orthogonal polynomials associated with varying weights play a key role in analyzing random matrices and other topics.  This book will be of use to a wide community of mathematicians, physicists, and statisticians dealing with techniques of potential theory, orthogonal polynomials, approximation theory, as well as random matrices. .

High throughput screening and profiling of high-value carotenoids from a wide diversity of bacteria in surface seawater.

Science.gov (United States)

Asker, Dalal

2018-09-30

Carotenoids are valuable natural colorants that exhibit numerous health promoting properties, and thus are widely used in food, feeds, pharmaceutical and nutraceuticals industries. In this study, we isolated and identified novel microbial sources that produced high-value carotenoids using high throughput screening (HTS). A total of 701 pigmented microbial strains library including marine bacteria and red yeast was constructed. Carotenoids profiling using HPLC-DAD-MS methods showed 88 marine bacterial strains with potential for the production of high-value carotenoids including astaxanthin (28 strains), zeaxanthin (21 strains), lutein (1 strains) and canthaxanthin (2 strains). A comprehensive 16S rRNA gene based phylogenetic analysis revealed that these strains can be classified into 30 species belonging to five bacterial classes (Flavobacteriia, α-Proteobacteria, γ-Proteobacteria, Actinobacteria and Bacilli). Importantly, we discovered novel producers of zeaxanthin and lutein, and a high diversity in both carotenoids and producing microbial strains, which are promising and highly selective biotechnological sources for high-value carotenoids. Copyright © 2018 Elsevier Ltd. All rights reserved.

Performance of a solar chimney by varying design parameters

CSIR Research Space (South Africa)

Kumirai, T

2015-08-01

Full Text Available the design of solar chimneys to ensure optimal performance. The purpose of this chapter is to discuss the performance of an example solar chimney by varying the design parameters and examining their effects on the interior ventilation performance... chimney by varying design parameters Tichaona Kumirai, Researcher, Built Environment CSIR Jan-Hendrik Grobler, DPSS CSIR Dr D.C.U. Conradie, Senior researcher, Built Environment CSIR 1 Introduction Trombe walls and solar chimneys are not widely...

Tracking time-varying coefficient-functions

DEFF Research Database (Denmark)

Nielsen, Henrik Aalborg; Nielsen, Torben Skov; Joensen, Alfred K.

2000-01-01

is a combination of recursive least squares with exponential forgetting and local polynomial regression. It is argued, that it is appropriate to let the forgetting factor vary with the value of the external signal which is the argument of the coefficient functions. Some of the key properties of the modified method...... are studied by simulation...

Response-only modal identification using random decrement algorithm with time-varying threshold level

International Nuclear Information System (INIS)

Lin, Chang Sheng; Tseng, Tse Chuan

2014-01-01

Modal Identification from response data only is studied for structural systems under nonstationary ambient vibration. The topic of this paper is the estimation of modal parameters from nonstationary ambient vibration data by applying the random decrement algorithm with time-varying threshold level. In the conventional random decrement algorithm, the threshold level for evaluating random dec signatures is defined as the standard deviation value of response data of the reference channel. The distortion of random dec signatures may be, however, induced by the error involved in noise from the original response data in practice. To improve the accuracy of identification, a modification of the sampling procedure in random decrement algorithm is proposed for modal-parameter identification from the nonstationary ambient response data. The time-varying threshold level is presented for the acquisition of available sample time history to perform averaging analysis, and defined as the temporal root-mean-square function of structural response, which can appropriately describe a wide variety of nonstationary behaviors in reality, such as the time-varying amplitude (variance) of a nonstationary process in a seismic record. Numerical simulations confirm the validity and robustness of the proposed modal-identification method from nonstationary ambient response data under noisy conditions.

The deforestation debate; estimates vary widely over the extent of forest loss

International Nuclear Information System (INIS)

Monastersky, R.

1993-01-01

While tropical forests are vanishing at a disturbing rate, the wide-spread disagreement over deforestation estimates makes it difficult for government officials and scientists to assess the problem. In turn this hampers efforts to gauge the threat of related issues such as habitat destruction and global warming. Creating more confusion is the realization that partly deforested, but not stripped, lands have not been completely taken into account. In addition lands in tropical regions but outside the tropical rain forest are poorly represented. This article uses Brazil as an example of the conflicting estimates. The efforts of the United Nations Food and Agriculture Organization (FAO) to improve its estimates are described. An on-going NASA project to help is also described

Estimating varying coefficients for partial differential equation models.

Science.gov (United States)

Zhang, Xinyu; Cao, Jiguo; Carroll, Raymond J

2017-09-01

Partial differential equations (PDEs) are used to model complex dynamical systems in multiple dimensions, and their parameters often have important scientific interpretations. In some applications, PDE parameters are not constant but can change depending on the values of covariates, a feature that we call varying coefficients. We propose a parameter cascading method to estimate varying coefficients in PDE models from noisy data. Our estimates of the varying coefficients are shown to be consistent and asymptotically normally distributed. The performance of our method is evaluated by a simulation study and by an empirical study estimating three varying coefficients in a PDE model arising from LIDAR data. © 2017, The International Biometric Society.

Precision of bone densitometry measurements: When is change true change and does it vary across bone density values?

International Nuclear Information System (INIS)

Wong, J.C.H.; Griffiths, M.R.

2003-01-01

The precision error of the bone densitometer is used to interpret significant change in bone mineral density (BMD) in serial studies. The precision error can be expressed as standard deviation (SD) or coefficient of variation (CV). The aims of this study are to determine the precision error over a range of BMD values and to demonstrate the application of the precision error in clinical practice. A bone phantom was used consisting of a perspex block with eight compartments containing varying amounts of hydroxyapatite powder to simulate a range of bone densities. The block was scanned 21 times and manual regions placed over each compartment to measure the BMD in each compartment. There were no significant differences in the variances or SD for all eight compartments, that is, over the range of BMD normally encountered in clinical practice. However, the calculated CV show a progressive fall in values as the BMD rises. Therefore, the SD should be used to calculate significant BMD change. In a practise with quality control procedures in place to detect calibration drift and with appropriately trained personnel, a change of approximately 0.05 g/cm 2 is generally regarded as being a significant change at a 95% confidence level. Copyright (2003) Blackwell Science Pty Ltd

Wide-band segmented power distribution networks

NARCIS (Netherlands)

Tereshchenko, O.V.; Buesink, Frederik Johannes Karel; Leferink, Frank Bernardus Johannes

2013-01-01

This paper discusses a novel design of Power Distribution Network (PDN). By physical structuring of the power plane into repetitive symmetrical and asymmetrical segments of varying size, suppression of the propagation of unwanted noise throughout the PDN over a wide frequency range is achieved.

Design of 2D time-varying vector fields.

Science.gov (United States)

Chen, Guoning; Kwatra, Vivek; Wei, Li-Yi; Hansen, Charles D; Zhang, Eugene

2012-10-01

Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a framework for the design of time-varying vector fields, both for planar domains as well as manifold surfaces. Our system supports the creation and modification of various time-varying vector fields with desired spatial and temporal characteristics through several design metaphors, including streamlines, pathlines, singularity paths, and bifurcations. These design metaphors are integrated into an element-based design to generate the time-varying vector fields via a sequence of basis field summations or spatial constrained optimizations at the sampled times. The key-frame design and field deformation are also introduced to support other user design scenarios. Accordingly, a spatial-temporal constrained optimization and the time-varying transformation are employed to generate the desired fields for these two design scenarios, respectively. We apply the time-varying vector fields generated using our design system to a number of important computer graphics applications that require controllable dynamic effects, such as evolving surface appearance, dynamic scene design, steerable crowd movement, and painterly animation. Many of these are difficult or impossible to achieve via prior simulation-based methods. In these applications, the time-varying vector fields have been applied as either orientation fields or advection fields to control the instantaneous appearance or evolving trajectories of the dynamic effects.

Global value chains: Building blocks and network dynamics

Science.gov (United States)

Tsekeris, Theodore

2017-12-01

The paper employs measures and tools from complex network analysis to enhance the understanding and interpretation of structural characteristics pertaining to the Global Value Chains (GVCs) during the period 1995-2011. The analysis involves the country, sector and country-sector value chain networks to identify main drivers of structural change. The results indicate significant intertemporal changes, mirroring the increased globalization in terms of network size, strength and connectivity. They also demonstrate higher clustering and increased concentration of the most influential countries and country-sectors relative to all others in the GVC network, with the geographical dimension to prevail over the sectoral dimension in the formation of value chains. The regionalization and less hierarchical organization drive country-sector production sharing, while the sectoral value chain network has become more integrated and more competitive over time. The findings suggest that the impact of country-sector policies and/or shocks may vary with the own-group and network-wide influence of each country, take place in multiple geographical scales, as GVCs have a block structure, and involve time dynamics.

Global Stability of Polytopic Linear Time-Varying Dynamic Systems under Time-Varying Point Delays and Impulsive Controls

Directory of Open Access Journals (Sweden)

M. de la Sen

2010-01-01

Full Text Available This paper investigates the stability properties of a class of dynamic linear systems possessing several linear time-invariant parameterizations (or configurations which conform a linear time-varying polytopic dynamic system with a finite number of time-varying time-differentiable point delays. The parameterizations may be timevarying and with bounded discontinuities and they can be subject to mixed regular plus impulsive controls within a sequence of time instants of zero measure. The polytopic parameterization for the dynamics associated with each delay is specific, so that (q+1 polytopic parameterizations are considered for a system with q delays being also subject to delay-free dynamics. The considered general dynamic system includes, as particular cases, a wide class of switched linear systems whose individual parameterizations are timeinvariant which are governed by a switching rule. However, the dynamic system under consideration is viewed as much more general since it is time-varying with timevarying delays and the bounded discontinuous changes of active parameterizations are generated by impulsive controls in the dynamics and, at the same time, there is not a prescribed set of candidate potential parameterizations.

Stagewise pseudo-value regression for time-varying effects on the cumulative incidence

DEFF Research Database (Denmark)

Zöller, Daniela; Schmidtmann, Irene; Weinmann, Arndt

2016-01-01

In a competing risks setting, the cumulative incidence of an event of interest describes the absolute risk for this event as a function of time. For regression analysis, one can either choose to model all competing events by separate cause-specific hazard models or directly model the association...... for time-varying effects. This is implemented by coupling variable selection between the grid times, but determining estimates separately. The effect estimates are regularized to also allow for model fitting with a low to moderate number of observations. This technique is illustrated in an application...

Design of 2D Time-Varying Vector Fields

KAUST Repository

Chen, Guoning

2012-10-01

Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a framework for the design of time-varying vector fields, both for planar domains as well as manifold surfaces. Our system supports the creation and modification of various time-varying vector fields with desired spatial and temporal characteristics through several design metaphors, including streamlines, pathlines, singularity paths, and bifurcations. These design metaphors are integrated into an element-based design to generate the time-varying vector fields via a sequence of basis field summations or spatial constrained optimizations at the sampled times. The key-frame design and field deformation are also introduced to support other user design scenarios. Accordingly, a spatial-temporal constrained optimization and the time-varying transformation are employed to generate the desired fields for these two design scenarios, respectively. We apply the time-varying vector fields generated using our design system to a number of important computer graphics applications that require controllable dynamic effects, such as evolving surface appearance, dynamic scene design, steerable crowd movement, and painterly animation. Many of these are difficult or impossible to achieve via prior simulation-based methods. In these applications, the time-varying vector fields have been applied as either orientation fields or advection fields to control the instantaneous appearance or evolving trajectories of the dynamic effects. © 1995-2012 IEEE.

Design of 2D Time-Varying Vector Fields

KAUST Repository

Chen, Guoning; Kwatra, Vivek; Wei, Li-Yi; Hansen, Charles D.; Zhang, Eugene

2012-01-01

Design of time-varying vector fields, i.e., vector fields that can change over time, has a wide variety of important applications in computer graphics. Existing vector field design techniques do not address time-varying vector fields. In this paper, we present a framework for the design of time-varying vector fields, both for planar domains as well as manifold surfaces. Our system supports the creation and modification of various time-varying vector fields with desired spatial and temporal characteristics through several design metaphors, including streamlines, pathlines, singularity paths, and bifurcations. These design metaphors are integrated into an element-based design to generate the time-varying vector fields via a sequence of basis field summations or spatial constrained optimizations at the sampled times. The key-frame design and field deformation are also introduced to support other user design scenarios. Accordingly, a spatial-temporal constrained optimization and the time-varying transformation are employed to generate the desired fields for these two design scenarios, respectively. We apply the time-varying vector fields generated using our design system to a number of important computer graphics applications that require controllable dynamic effects, such as evolving surface appearance, dynamic scene design, steerable crowd movement, and painterly animation. Many of these are difficult or impossible to achieve via prior simulation-based methods. In these applications, the time-varying vector fields have been applied as either orientation fields or advection fields to control the instantaneous appearance or evolving trajectories of the dynamic effects. © 1995-2012 IEEE.

Values exchange: using online technology to raise awareness of values and ethics in radiography education.

Science.gov (United States)

Mc Inerney, John; Lees, Amanda

2018-03-01

Ethics and values are increasingly significant aspects of patient-centred healthcare. While it is widely agreed that ethics and values are essential for healthcare delivery, there is also an acknowledgement that these are areas that are challenging to teach. The purpose of this study is to report a small-scale evaluative research project of a web-based technology with the educational potential to facilitate learning in relation to ethics, values, self-reflection and peer-based learning. Five diagnostic radiography students took part in a semi-structured focus group with the aim of exploring their experiences of using Values Exchange, an online ethical decision-making framework, to examine practice-based ethical issues. Transcripts were interrogated for key themes. From the thematic analysis three major themes emerged, understanding and appreciating others, addressing the theory-practice gap and delivering a safe and effective learning environment. Perceived limitations of the platform included students' fear of misinterpreted responses and possibility of poor group dynamics. There are varied approaches to how ethics and values are taught and assessed within health-related environments. Values Exchange is one such teaching tool and has been investigated and described positively by radiography students in this study. Online teaching tools can have a positive effect in helping students identify their own values but require skilled implementation to reap positive rewards. © 2018 The Authors. Journal of Medical Radiation Sciences published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Medical Imaging and Radiation Therapy and New Zealand Institute of Medical Radiation Technology.

Behavior of varying-alpha cosmologies

International Nuclear Information System (INIS)

Barrow, John D.; Sandvik, Haavard Bunes; Magueijo, Joao

2002-01-01

We determine the behavior of a time-varying fine structure 'constant' α(t) during the early and late phases of universes dominated by the kinetic energy of changing α(t), radiation, dust, curvature, and lambda, respectively. We show that after leaving an initial vacuum-dominated phase during which α increases, α remains constant in universes such as our own during the radiation era, and then increases slowly, proportional to a logarithm of cosmic time, during the dust era. If the universe becomes dominated by a negative curvature or a positive cosmological constant then α tends rapidly to a constant value. The effect of an early period of de Sitter or power-law inflation is to drive α to a constant value. Various cosmological consequences of these results are discussed with reference to recent observational studies of the value of α from quasar absorption spectra and to the existence of life in expanding universes

The Value of Information for Populations in Varying Environments

Science.gov (United States)

Rivoire, Olivier; Leibler, Stanislas

2011-04-01

The notion of information pervades informal descriptions of biological systems, but formal treatments face the problem of defining a quantitative measure of information rooted in a concept of fitness, which is itself an elusive notion. Here, we present a model of population dynamics where this problem is amenable to a mathematical analysis. In the limit where any information about future environmental variations is common to the members of the population, our model is equivalent to known models of financial investment. In this case, the population can be interpreted as a portfolio of financial assets and previous analyses have shown that a key quantity of Shannon's communication theory, the mutual information, sets a fundamental limit on the value of information. We show that this bound can be violated when accounting for features that are irrelevant in finance but inherent to biological systems, such as the stochasticity present at the individual level. This leads us to generalize the measures of uncertainty and information usually encountered in information theory.

Spatially varying dispersion to model breakthrough curves.

Science.gov (United States)

Li, Guangquan

2011-01-01

Often the water flowing in a karst conduit is a combination of contaminated water entering at a sinkhole and cleaner water released from the limestone matrix. Transport processes in the conduit are controlled by advection, mixing (dilution and dispersion), and retention-release. In this article, a karst transport model considering advection, spatially varying dispersion, and dilution (from matrix seepage) is developed. Two approximate Green's functions are obtained using transformation of variables, respectively, for the initial-value problem and for the boundary-value problem. A numerical example illustrates that mixing associated with strong spatially varying conduit dispersion can cause strong skewness and long tailing in spring breakthrough curves. Comparison of the predicted breakthrough curve against that measured from a dye-tracing experiment between Ames Sink and Indian Spring, Northwest Florida, shows that the conduit dispersivity can be as large as 400 m. Such a large number is believed to imply strong solute interaction between the conduit and the matrix and/or multiple flow paths in a conduit network. It is concluded that Taylor dispersion is not dominant in transport in a karst conduit, and the complicated retention-release process between mobile- and immobile waters may be described by strong spatially varying conduit dispersion. Copyright © 2010 The Author(s). Journal compilation © 2010 National Ground Water Association.

A wide range and highly sensitive optical fiber pH sensor using polyacrylamide hydrogel

Science.gov (United States)

Pathak, Akhilesh Kumar; Singh, Vinod Kumar

2017-12-01

In the present study we report the fabrication and characterization of no-core fiber sensor (NCFS) using smart hydrogel coating for pH measurement. The no-core fiber (NCF) is stubbed between two single-mode fibers with SMA connector before immobilizing of smart hydrogel. The wavelength interrogation technique is used to calculate the sensitivity of the proposed sensor. The result shows a high sensitivity of 1.94 nm/pH for a wide range of pH values varied from 3 to 10 with a good linear response. In addition to high sensitivity, the fabricated sensor provides a fast response time with a good stability, repeatability and reproducibility.

Conceptual Modeling of Time-Varying Information

DEFF Research Database (Denmark)

Gregersen, Heidi; Jensen, Christian S.

2004-01-01

A wide range of database applications manage information that varies over time. Many of the underlying database schemas of these were designed using the Entity-Relationship (ER) model. In the research community as well as in industry, it is common knowledge that the temporal aspects of the mini......-world are important, but difficult to capture using the ER model. Several enhancements to the ER model have been proposed in an attempt to support the modeling of temporal aspects of information. Common to the existing temporally extended ER models, few or no specific requirements to the models were given...

Time-varying extreme value dependence with application to leading European stock markets

KAUST Repository

Castro-Camilo, Daniela; de Carvalho, Miguel; Wadsworth, Jennifer

2018-01-01

Extremal dependence between international stock markets is of particular interest in today’s global financial landscape. However, previous studies have shown this dependence is not necessarily stationary over time. We concern ourselves with modeling extreme value dependence when that dependence is changing over time, or other suitable covariate. Working within a framework of asymptotic dependence, we introduce a regression model for the angular density of a bivariate extreme value distribution that allows us to assess how extremal dependence evolves over a covariate. We apply the proposed model to assess the dynamics governing extremal dependence of some leading European stock markets over the last three decades, and find evidence of an increase in extremal dependence over recent years.

Time-varying extreme value dependence with application to leading European stock markets

KAUST Repository

Castro-Camilo, Daniela

2018-03-09

Extremal dependence between international stock markets is of particular interest in today’s global financial landscape. However, previous studies have shown this dependence is not necessarily stationary over time. We concern ourselves with modeling extreme value dependence when that dependence is changing over time, or other suitable covariate. Working within a framework of asymptotic dependence, we introduce a regression model for the angular density of a bivariate extreme value distribution that allows us to assess how extremal dependence evolves over a covariate. We apply the proposed model to assess the dynamics governing extremal dependence of some leading European stock markets over the last three decades, and find evidence of an increase in extremal dependence over recent years.

Tangential boundary values of Laplace transforms. Applications to Muntz-Szasz type approximation

Science.gov (United States)

Sedletskii, A. M.

2003-02-01

We consider the Laplace transforms (LT) of functions in L^q(\\mathbb R_+), 1, with a slowly varying weight. We prove that if the weight satisfies certain conditions, then each LT of this class has tangential boundary values almost everywhere on the imaginary axis, and the structure of the corresponding neighbourhoods depends on the weight only. This result is applied to distinguish a wide class of weighted L^p spaces on the half-line such that the Szasz condition is not necessary for the completeness of the system \\exp(-\\lambda_n t) in these spaces.

An Adaptive Noise Cancellation System Based on Linear and Widely Linear Complex Valued Least Mean Square Algorithms for Removing Electrooculography Artifacts from Electroencephalography Signals

Directory of Open Access Journals (Sweden)

Engin Cemal MENGÜÇ

2018-03-01

Full Text Available In this study, an adaptive noise cancellation (ANC system based on linear and widely linear (WL complex valued least mean square (LMS algorithms is designed for removing electrooculography (EOG artifacts from electroencephalography (EEG signals. The real valued EOG and EEG signals (Fp1 and Fp2 given in dataset are primarily expressed as a complex valued signal in the complex domain. Then, using the proposed ANC system, the EOG artifacts are eliminated in the complex domain from the EEG signals. Expression of these signals in the complex domain allows us to remove EOG artifacts from two EEG channels simultaneously. Moreover, in this study, it has been shown that the complex valued EEG signal exhibits noncircular behavior, and in the case, the WL-CLMS algorithm enhances the performance of the ANC system compared to real-valued LMS and CLMS algorithms. Simulation results support the proposed approach.

Information Superiority and Game Theory: The Value of Varying Levels of Information

National Research Council Canada - National Science Library

McIntosh, Gary

2002-01-01

.... This thesis examines how various levels of information and information superiority affect strategy choices and decision-making in determining the payoff value for opposing forces in a classic zero-sum two-sided contest...

Mediation analysis with time varying exposures and mediators.

Science.gov (United States)

VanderWeele, Tyler J; Tchetgen Tchetgen, Eric J

2017-06-01

In this paper we consider causal mediation analysis when exposures and mediators vary over time. We give non-parametric identification results, discuss parametric implementation, and also provide a weighting approach to direct and indirect effects based on combining the results of two marginal structural models. We also discuss how our results give rise to a causal interpretation of the effect estimates produced from longitudinal structural equation models. When there are time-varying confounders affected by prior exposure and mediator, natural direct and indirect effects are not identified. However, we define a randomized interventional analogue of natural direct and indirect effects that are identified in this setting. The formula that identifies these effects we refer to as the "mediational g-formula." When there is no mediation, the mediational g-formula reduces to Robins' regular g-formula for longitudinal data. When there are no time-varying confounders affected by prior exposure and mediator values, then the mediational g-formula reduces to a longitudinal version of Pearl's mediation formula. However, the mediational g-formula itself can accommodate both mediation and time-varying confounders and constitutes a general approach to mediation analysis with time-varying exposures and mediators.

Robust Stabilization of Nonlinear Systems with Uncertain Varying Control Coefficient

Directory of Open Access Journals (Sweden)

Zaiyue Yang

2014-01-01

Full Text Available This paper investigates the stabilization problem for a class of nonlinear systems, whose control coefficient is uncertain and varies continuously in value and sign. The study emphasizes the development of a robust control that consists of a modified Nussbaum function to tackle the uncertain varying control coefficient. By such a method, the finite-time escape phenomenon has been prevented when the control coefficient is crossing zero and varying its sign. The proposed control guarantees the asymptotic stabilization of the system and boundedness of all closed-loop signals. The control performance is illustrated by a numerical simulation.

Chemical composition, nutritive value, and toxicological evaluation of Bauhinia cheilantha seeds: a legume from semiarid regions widely used in folk medicine.

Science.gov (United States)

Teixeira, Daniel Câmara; Farias, Davi Felipe; Carvalho, Ana Fontenele Urano; Arantes, Mariana Reis; Oliveira, José Tadeu Abreu; Sousa, Daniele Oliveira Bezerra; Pereira, Mirella Leite; Oliveira, Hermogenes David; Andrade-Neto, Manoel; Vasconcelos, Ilka Maria

2013-01-01

Among the Bauhinia species, B. cheilantha stands out for its seed protein content. However, there is no record of its nutritional value, being used in a nonsustainable way in the folk medicine and for large-scale extraction of timber. The aim of this study was to investigate the food potential of B. cheilantha seeds with emphasis on its protein quality to provide support for flora conservation and use as raw material or as prototype for the development of bioproducts with high added socioeconomic value. B. cheilantha seeds show high protein content (35.9%), reasonable essential amino acids profile, low levels of antinutritional compounds, and nutritional parameters comparable to those of legumes widely used such as soybean and cowpea. The heat treatment of the seeds as well as the protein extraction process (to obtain the protein concentrate) increased the acceptance of diets by about 100% when compared to that of raw Bc diet. These wild legume seeds can be promising alternative source of food to overcome the malnutrition problem faced by low income people adding socioeconomic value to the species.

Comparison of different Kalman filter approaches in deriving time varying connectivity from EEG data.

Science.gov (United States)

Ghumare, Eshwar; Schrooten, Maarten; Vandenberghe, Rik; Dupont, Patrick

2015-08-01

Kalman filter approaches are widely applied to derive time varying effective connectivity from electroencephalographic (EEG) data. For multi-trial data, a classical Kalman filter (CKF) designed for the estimation of single trial data, can be implemented by trial-averaging the data or by averaging single trial estimates. A general linear Kalman filter (GLKF) provides an extension for multi-trial data. In this work, we studied the performance of the different Kalman filtering approaches for different values of signal-to-noise ratio (SNR), number of trials and number of EEG channels. We used a simulated model from which we calculated scalp recordings. From these recordings, we estimated cortical sources. Multivariate autoregressive model parameters and partial directed coherence was calculated for these estimated sources and compared with the ground-truth. The results showed an overall superior performance of GLKF except for low levels of SNR and number of trials.

Tangential boundary values of Laplace transforms. Applications to Muntz-Szasz type approximation

Energy Technology Data Exchange (ETDEWEB)

Sedletskii, A M [M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

2003-02-28

We consider the Laplace transforms (LT) of functions in L{sup q}(R{sub +}), 1varying weight. We prove that if the weight satisfies certain conditions, then each LT of this class has tangential boundary values almost everywhere on the imaginary axis, and the structure of the corresponding neighbourhoods depends on the weight only. This result is applied to distinguish a wide class of weighted L{sup p} spaces on the half-line such that the Szasz condition is not necessary for the completeness of the system exp(-{lambda}{sub n}t) in these spaces.

The effect of wide swathing on wilting times and nutritive value of alfalfa haylage.

Science.gov (United States)

Kung, L; Stough, E C; McDonell, E E; Schmidt, R J; Hofherr, M W; Reich, L J; Klingerman, C M

2010-04-01

On 3 consecutive cuttings, alfalfa from a single field was mowed with a John Deere 946 mower-conditioner (4-m cut width; Moline, IL) to leave narrow swaths (NS) ranging from 1.2 to 1.52 m wide (30-37% of cutter bar width) and wide swaths (WS) ranging from 2.44 to 2.74 m wide (62-67% of cutter bar width). Samples were collected from windrows and dry matter (DM) was monitored during wilting until a target of 43 to 45% DM was obtained. Forage from random windrows (n=4-6) was harvested by hand, chopped through a forage harvester before being packed in replicated vacuum-sealed bags, and allowed to ensile for 65 d. There was no swath width x cutting interaction for any parameter tested. Over all cuttings, the resulting silage DM was not different between the NS silage (43.8%) and the WS silage (44.9%). However, wide swathing greatly reduced the time of wilting before making silage. The hours of wilting time needed to reach the targeted DM for the NS silage compared with the WS silage at cuttings 1, 2, and 3 were 50 versus 29, 54 versus 28, and 25 versus 6, respectively. At the time of ensiling, the WS silage had more water-soluble carbohydrates (5.1%) than did the NS silage (3.7%). The WS silage had a lower pH (4.58) than did the NS silage (4.66), but swath width did not affect fermentation end products (lactic acid, acetic acid, and ethanol). The NS silage had more NH(3)-N (0.26%) than did the WS silage (0.21%). Wide swathing did not affect the concentration of ash or the digestibility of NDF, but it lowered the N content (NS=3.45%; WS=3.23%) and increased the ADF content (NS=39.7%; WS=40.9%) of the resulting silage. Wide swathing can markedly reduce the time that alfalfa must wilt before it can be chopped for silage, but under good conditions, as in this study, the resulting silage quality was generally not improved. Copyright (c) 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Establishment of detailed reference values for luteinizing hormone, follicle stimulating hormone, estradiol, and progesterone during different phases of the menstrual cycle on the Abbott ARCHITECT® analyzer

OpenAIRE

Stricker, Reto; Eberhart, Raphael; Chevailler, Marie-Christine; Quinn, Frank A.; Bischof, Paul; Stricker, René

2017-01-01

During a normal menstrual cycle, serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, and progesterone can vary widely between cycles for the same woman, as well as between different woman. Reliable reference values based on the local population are important for correct interpretation of laboratory results. The purpose of our study was to determine detailed reference values for these hormones throughout the menstrual cycle using the Abbott ARCHITECT system...

Extreme value distributions

CERN Document Server

Ahsanullah, Mohammad

2016-01-01

The aim of the book is to give a through account of the basic theory of extreme value distributions. The book cover a wide range of materials available to date. The central ideas and results of extreme value distributions are presented. The book rwill be useful o applied statisticians as well statisticians interrested to work in the area of extreme value distributions.vmonograph presents the central ideas and results of extreme value distributions.The monograph gives self-contained of theory and applications of extreme value distributions.

Genome-wide association study of pathological gambling.

Science.gov (United States)

Lang, M; Leménager, T; Streit, F; Fauth-Bühler, M; Frank, J; Juraeva, D; Witt, S H; Degenhardt, F; Hofmann, A; Heilmann-Heimbach, S; Kiefer, F; Brors, B; Grabe, H-J; John, U; Bischof, A; Bischof, G; Völker, U; Homuth, G; Beutel, M; Lind, P A; Medland, S E; Slutske, W S; Martin, N G; Völzke, H; Nöthen, M M; Meyer, C; Rumpf, H-J; Wurst, F M; Rietschel, M; Mann, K F

2016-08-01

Pathological gambling is a behavioural addiction with negative economic, social, and psychological consequences. Identification of contributing genes and pathways may improve understanding of aetiology and facilitate therapy and prevention. Here, we report the first genome-wide association study of pathological gambling. Our aims were to identify pathways involved in pathological gambling, and examine whether there is a genetic overlap between pathological gambling and alcohol dependence. Four hundred and forty-five individuals with a diagnosis of pathological gambling according to the Diagnostic and Statistical Manual of Mental Disorders were recruited in Germany, and 986 controls were drawn from a German general population sample. A genome-wide association study of pathological gambling comprising single marker, gene-based, and pathway analyses, was performed. Polygenic risk scores were generated using data from a German genome-wide association study of alcohol dependence. No genome-wide significant association with pathological gambling was found for single markers or genes. Pathways for Huntington's disease (P-value=6.63×10(-3)); 5'-adenosine monophosphate-activated protein kinase signalling (P-value=9.57×10(-3)); and apoptosis (P-value=1.75×10(-2)) were significant. Polygenic risk score analysis of the alcohol dependence dataset yielded a one-sided nominal significant P-value in subjects with pathological gambling, irrespective of comorbid alcohol dependence status. The present results accord with previous quantitative formal genetic studies which showed genetic overlap between non-substance- and substance-related addictions. Furthermore, pathway analysis suggests shared pathology between Huntington's disease and pathological gambling. This finding is consistent with previous imaging studies. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Conductivity studies of lithium zinc silicate glasses with varying ...

Indian Academy of Sciences (India)

WINTEC

Values of activation energy derived from σd.c., ωh and τ are almost equal within the ... materials can be changed by varying the proportion of the .... The solid line is a guide to the eye. ... does not show a maximum as d.c. conductivity drops to a.

Development of Industry-Wide IS Integration Model in the Agri-Industry

DEFF Research Database (Denmark)

Hedman, Jonas; Henningsson, Stefan

2013-01-01

his paper presents a model explaining industrywide information systems (IS) integration in the agri-industry.Using a theoretical frame of value confi guration analysis and IS integration extent we study 15 organizations. We find that product sensitivity, continuous production, value chain captains...... sensitivity and continuous production process led to higher levels of integration......., and value creation logic explain the industry-wide IS integration. Incompatible value creation logic among stakeholders and the lack of presence of “value chain captains” – powerful actors dominating the entire industry - has and negative impact on industry-wide integration. On the other hand, product...

Estimating Time-Varying PCB Exposures Using Person-Specific Predictions to Supplement Measured Values: A Comparison of Observed and Predicted Values in Two Cohorts of Norwegian Women

Science.gov (United States)

Nøst, Therese Haugdahl; Breivik, Knut; Wania, Frank; Rylander, Charlotta; Odland, Jon Øyvind; Sandanger, Torkjel Manning

2015-01-01

, Rylander C, Odland JØ, Sandanger TM. 2016. Estimating time-varying PCB exposures using person-specific predictions to supplement measured values: a comparison of observed and predicted values in two cohorts of Norwegian women. Environ Health Perspect 124:299–305; http://dx.doi.org/10.1289/ehp.1409191 PMID:26186800

Estimating System-wide Impacts of Smart Grid Demonstrations

Energy Technology Data Exchange (ETDEWEB)

Schneider, Kevin P.; Lightner, Eric M.; Fuller, Jason C.

2015-03-01

Quantifying the impact of a new technology on a single specific distribution feeder is relatively easy, but it does not provide insight into the complexities and variations of a system-wide deployment. It is the inability to extrapolate system-wide impacts that hinders the deployment of many promising new technologies. This paper presents a method of extrapolating technology impacts, either simulated or from a field demonstration, from a limited number of distribution feeders to a system-wide impact. The size of the system can vary from the service territory of a single utility, to a region, or to an entire country. The paper will include an example analysis using the United States Department of Energy (DOE) funded Smart Grid Investment Grant (SGIG) projects, extrapolating their benefits to a national level.

Slowly varying dilaton cosmologies and their field theory duals

International Nuclear Information System (INIS)

Awad, Adel; Das, Sumit R.; Ghosh, Archisman; Oh, Jae-Hyuk; Trivedi, Sandip P.

2009-01-01

We consider a deformation of the AdS 5 xS 5 solution of IIB supergravity obtained by taking the boundary value of the dilaton to be time dependent. The time dependence is taken to be slowly varying on the anti-de Sitter (AdS) scale thereby introducing a small parameter ε. The boundary dilaton has a profile which asymptotes to a constant in the far past and future and attains a minimum value at intermediate times. We construct the supergravity (sugra) solution to first nontrivial order in ε, and find that it is smooth, horizon-free, and asymptotically AdS 5 xS 5 in the far future. When the intermediate values of the dilaton becomes small enough the curvature becomes of order the string scale and the sugra approximation breaks down. The resulting dynamics is analyzed in the dual SU(N) gauge theory on S 3 with a time dependent coupling constant which varies slowly. When Nε 5 xS 5 again. When Nε>>1, we formulate a classical adiabatic perturbation theory based on coherent states which arises in the large N limit. For large values of the 't Hooft coupling this reproduces the supergravity results. For small 't Hooft coupling the coherent state calculations become involved and we cannot reach a definite conclusion. We argue that the final state should have a dual description which is mostly smooth AdS 5 space with the possible presence of a small black hole.

FGWAS: Functional genome wide association analysis.

Science.gov (United States)

Huang, Chao; Thompson, Paul; Wang, Yalin; Yu, Yang; Zhang, Jingwen; Kong, Dehan; Colen, Rivka R; Knickmeyer, Rebecca C; Zhu, Hongtu

2017-10-01

Functional phenotypes (e.g., subcortical surface representation), which commonly arise in imaging genetic studies, have been used to detect putative genes for complexly inherited neuropsychiatric and neurodegenerative disorders. However, existing statistical methods largely ignore the functional features (e.g., functional smoothness and correlation). The aim of this paper is to develop a functional genome-wide association analysis (FGWAS) framework to efficiently carry out whole-genome analyses of functional phenotypes. FGWAS consists of three components: a multivariate varying coefficient model, a global sure independence screening procedure, and a test procedure. Compared with the standard multivariate regression model, the multivariate varying coefficient model explicitly models the functional features of functional phenotypes through the integration of smooth coefficient functions and functional principal component analysis. Statistically, compared with existing methods for genome-wide association studies (GWAS), FGWAS can substantially boost the detection power for discovering important genetic variants influencing brain structure and function. Simulation studies show that FGWAS outperforms existing GWAS methods for searching sparse signals in an extremely large search space, while controlling for the family-wise error rate. We have successfully applied FGWAS to large-scale analysis of data from the Alzheimer's Disease Neuroimaging Initiative for 708 subjects, 30,000 vertices on the left and right hippocampal surfaces, and 501,584 SNPs. Copyright © 2017 Elsevier Inc. All rights reserved.

Vesicle biomechanics in a time-varying magnetic field.

Science.gov (United States)

Ye, Hui; Curcuru, Austen

2015-01-01

Cells exhibit distortion when exposed to a strong electric field, suggesting that the field imposes control over cellular biomechanics. Closed pure lipid bilayer membranes (vesicles) have been widely used for the experimental and theoretical studies of cellular biomechanics under this electrodeformation. An alternative method used to generate an electric field is by electromagnetic induction with a time-varying magnetic field. References reporting the magnetic control of cellular mechanics have recently emerged. However, theoretical analysis of the cellular mechanics under a time-varying magnetic field is inadequate. We developed an analytical theory to investigate the biomechanics of a modeled vesicle under a time-varying magnetic field. Following previous publications and to simplify the calculation, this model treated the inner and suspending media as lossy dielectrics, the membrane thickness set at zero, and the electric resistance of the membrane assumed to be negligible. This work provided the first analytical solutions for the surface charges, electric field, radial pressure, overall translational forces, and rotational torques introduced on a vesicle by the time-varying magnetic field. Frequency responses of these measures were analyzed, particularly the frequency used clinically by transcranial magnetic stimulation (TMS). The induced surface charges interacted with the electric field to produce a biomechanical impact upon the vesicle. The distribution of the induced surface charges depended on the orientation of the coil and field frequency. The densities of these charges were trivial at low frequency ranges, but significant at high frequency ranges. The direction of the radial force on the vesicle was dependent on the conductivity ratio between the vesicle and the medium. At relatively low frequencies (biomechanics under a time-varying magnetic field. Biological effects of clinical TMS are not likely to occur via alteration of the biomechanics of brain

Wide-angle imaging LIDAR (WAIL): a ground-based instrument for monitoring the thickness and density of optically thick clouds

International Nuclear Information System (INIS)

Love, Steven P.; Davis, A.B.; Rohde, C.A.; Ho, Cheng

2001-01-01

Traditional lidar provides little information on dense clouds beyond the range to their base (ceilometry), due to their extreme opacity. At most optical wavelengths, however, laser photons are not absorbed but merely scattered out of the beam, and thus eventually escape the cloud via multiple scattering, producing distinctive extended space- and time-dependent patterns which are, in essence, the cloud's radiative Green functions. These Green functions, essentially 'movies' of the time evolution of the spatial distribution of escaping light, are the primary data products of a new type of lidar: Wide Angle Imaging Lidar (WAIL). WAIL data can be used to infer both optical depth and physical thickness of clouds, and hence the cloud liquid water content. The instrumental challenge is to accommodate a radiance field varying over many orders of magnitude and changing over widely varying time-scales. Our implementation uses a high-speed microchannel plate/crossed delay line imaging detector system with a 60-degree full-angle field of view, and a 532 nm doubled Nd:YAG laser. Nighttime field experiments testing various solutions to this problem show excellent agreement with diffusion theory, and retrievals yield plausible values for the optical and geometrical parameters of the observed cloud decks.

Value-driven ERM: making ERM an engine for simultaneous value creation and value protection.

Science.gov (United States)

Celona, John; Driver, Jeffrey; Hall, Edward

2011-01-01

Enterprise risk management (ERM) began as an effort to integrate the historically disparate silos of risk management in organizations. More recently, as recognition has grown of the need to cover the upside risks in value creation (financial and otherwise), organizations and practitioners have been searching for the means to do this. Existing tools such as heat maps and risk registers are not adequate for this task. Instead, a conceptually new value-driven framework is needed to realize the promise of enterprise-wide coverage of all risks, for both value protection and value creation. The methodology of decision analysis provides the means of capturing systemic, correlated, and value-creation risks on the same basis as value protection risks and has been integrated into the value-driven approach to ERM described in this article. Stanford Hospital and Clinics Risk Consulting and Strategic Decisions Group have been working to apply this value-driven ERM at Stanford University Medical Center. © 2011 American Society for Healthcare Risk Management of the American Hospital Association.

Value dynamics and infrastructure reform

DEFF Research Database (Denmark)

Beck Jørgensen, Torben

2009-01-01

varying decision making contexts bear on the role of values and the handling of values. A number of theoretical explanations of value change are presented, from teleological explanations to pendulum dynamics and life cycle theories. The paper concludes with suggestions on how to deal with normative......This paper identifies the aspects of value dynamics in each of the previous papers: how the choice of institutional arrangements give primacy to some values and others not; the law and the market as separate dynamic forces; the different time horizons involved when studying value changes; and how...

Value Orientations of Future Teachers-Researchers

Science.gov (United States)

Botalova, Olga B.; Osipova, Seraphima V.; Asenova, Nazymgul S.; Kenenbaeva, Marzhan A.; Kuderina, Aizhan Y.; Zholtaeva, Gulnar; Boribekova, Farzana; Zhanatbekova, Nazym; Vedilina, Elena A.; Azanbekova, Gulnaz

2016-01-01

Values are keystones of society; they can vary depending on the professional activity. Teacher's values play an important role, since they directly affect the formation of knowledge of students. The paper presents the characteristics of one of the structural components of future teachers' active scientific position--pedagogic values such as…

Nonlinear Dynamics Modeling and Analysis of Torsional Spring-Loaded Antibacklash Gear with Time-Varying Meshing Stiffness and Friction

Directory of Open Access Journals (Sweden)

Zheng Yang

2013-01-01

Full Text Available Torsional spring-loaded antibacklash gear which can improve the transmission precision is widely used in many precision transmission fields. It is very important to investigate the dynamic characteristics of antibacklash gear. In the paper, applied force analysis is completed in detail. Then, defining the starting point of double-gear meshing as initial position, according to the meshing characteristic of antibacklash gear, single- or double-tooth meshing states of two gear pairs and the transformation relationship at any moment are determined. Based on this, a nonlinear model of antibacklash gear with time-varying friction and meshing stiffness is proposed. The influences of friction and variations of torsional spring stiffness, damping ratio and preload on dynamic transmission error (DTE are analyzed by numerical calculation and simulation, and the results show that antibacklash gear can increase the composite meshing stiffness; when the torsional spring stiffness is large enough, the oscillating components of the DTE (ODTE and the RMS of the DTE (RDTE trend to be a constant value; the variations of ODTE and RDTE are not significant, unless preload exceeds a certain value.

Enterprise-Wide Process & Performance Excellence:

DEFF Research Database (Denmark)

Edgeman, Rick; Kristensen, Kai; Eskildsen, Jacob Kjær

2013-01-01

Program value proposition, content, organization, and strategy are elaborated herein. This elaboration is the result of careful study of business and social trends, along with careful listening to collaborating enterprises. It is in this latter sense that the Enterprise-Wide Process & Performance...... Excellence certificate program is a product of a co-creation process....

Administrative database code accuracy did not vary notably with changes in disease prevalence.

Science.gov (United States)

van Walraven, Carl; English, Shane; Austin, Peter C

2016-11-01

Previous mathematical analyses of diagnostic tests based on the categorization of a continuous measure have found that test sensitivity and specificity varies significantly by disease prevalence. This study determined if the accuracy of diagnostic codes varied by disease prevalence. We used data from two previous studies in which the true status of renal disease and primary subarachnoid hemorrhage, respectively, had been determined. In multiple stratified random samples from the two previous studies having varying disease prevalence, we measured the accuracy of diagnostic codes for each disease using sensitivity, specificity, and positive and negative predictive value. Diagnostic code sensitivity and specificity did not change notably within clinically sensible disease prevalence. In contrast, positive and negative predictive values changed significantly with disease prevalence. Disease prevalence had no important influence on the sensitivity and specificity of diagnostic codes in administrative databases. Copyright © 2016 Elsevier Inc. All rights reserved.

Facilitating value co-creation in networks

DEFF Research Database (Denmark)

Rasmussen, Mette Apollo

participants in varied ways come to grasp the meaning of networking. The dissertation draws on insights from the Service-Dominant (S-D) Logic to explain how networks can be seen as spheres for value co-creation. Co-creation as a theoretical construct has evolved from varied streams of service marketing...... of networking. The concept of “imaginative value” (Beckert, 2011) is used to explain the oscillating behaviors observed in the two networks. Imaginative value can be defined as symbolic value that actors ascribe to an object, in this case the network. I argue that the group practices in the networks led......The dissertation investigates through two ethnographic case studies how value co-creation takes place in inter-organizational networks that have been facilitated by a municipality. The contribution of the study to business network research is the emphasis on development phases of networks...

Varying Constants, Gravitation and Cosmology

Directory of Open Access Journals (Sweden)

Jean-Philippe Uzan

2011-03-01

Full Text Available Fundamental constants are a cornerstone of our physical laws. Any constant varying in space and/or time would reflect the existence of an almost massless field that couples to matter. This will induce a violation of the universality of free fall. Thus, it is of utmost importance for our understanding of gravity and of the domain of validity of general relativity to test for their constancy. We detail the relations between the constants, the tests of the local position invariance and of the universality of free fall. We then review the main experimental and observational constraints that have been obtained from atomic clocks, the Oklo phenomenon, solar system observations, meteorite dating, quasar absorption spectra, stellar physics, pulsar timing, the cosmic microwave background and big bang nucleosynthesis. At each step we describe the basics of each system, its dependence with respect to the constants, the known systematic effects and the most recent constraints that have been obtained. We then describe the main theoretical frameworks in which the low-energy constants may actually be varying and we focus on the unification mechanisms and the relations between the variation of different constants. To finish, we discuss the more speculative possibility of understanding their numerical values and the apparent fine-tuning that they confront us with.

Debating Life on Mars: The Knowledge Integration Environment (KIE) in Varied School Settings.

Science.gov (United States)

Shear, Linda

Technology-enabled learning environments are beginning to come of age. Tools and frameworks are now available that have been shown to improve learning and are being deployed more widely in varied school settings. Teachers are now faced with the formidable challenge of integrating these promising new environments with the everyday context in which…

Time-varying market integration and expected returns in emerging mrkets

NARCIS (Netherlands)

de Jong, F.C.J.M.; de Roon, F.

2001-01-01

We use a simple model in which the expected returns in emerging markets depend on their systematicrisk as measured by their beta relative to the world portfolio as well as on the level ofintegration in that market. The level of integration is a time-varying variable that depends on themarket value

Reference values of spirometry for Finnish adults.

Science.gov (United States)

Kainu, A; Timonen, K L; Toikka, J; Qaiser, B; Pitkäniemi, J; Kotaniemi, J T; Lindqvist, A; Vanninen, E; Länsimies, E; Sovijärvi, A R A

2016-09-01

Diagnostic assessment of lung function necessitates up-to-date reference values. The aim of this study was to estimate reference values for spirometry for the Finnish population between 18 and 80 years and to compare them with the existing Finnish, European and the recently published global GLI2012 reference values. Spirometry was performed for 1380 adults in the population-based FinEsS studies and for 662 healthy non-smoking volunteer adults. Detailed predefined questionnaire screening of diseases and symptoms, and quality control of spirometry yielded a sample of 1000 native Finns (387 men) healthy non-smokers aged 18-83 years. Sex-specific reference values, which are estimated using the GAMLSS method and adjusted for age and height, are provided. The predicted values for lung volumes are larger than those obtained by GLI2012 prediction for the Caucasian subgroup for forced vital capacity (FVC) by an average 6·2% and 5·1% and forced expiratory volume in 1 s (FEV1) by an average 4·2% and 3·0% in men and women, respectively. GLI2012 slightly overestimated the ratio FEV1/FVC with an age-dependent trend. Most reference equations from other European countries, with the exception of the Swiss SAPALDIA study, showed an underestimation of FVC and FEV1 to varying degrees, and a slight overestimation of FEV1/FVC. This study offers up-to-date reference values of spirometry for native Finns with a wide age range. The GLI2012 predictions seem not to be suitable for clinical use for native Finns due to underestimation of lung volumes. © 2015 The Authors. Clinical Physiology and Functional Imaging published by John Wiley & Sons Ltd on behalf of Scandinavian Society of Clinical Physiology and Nuclear Medicine.

[Texture modified diet; digestibility, nutritional value, and contributions to menu of hospitals and nursing homes].

Science.gov (United States)

Irles Rocamora, Jose Antonio; García-Luna, Pedro Pablo

2014-01-21

Texture modified diet is a significant loss of the organoleptic qualities of the feed, so often associated with suboptimal intake and can increase the risk of malnutrition in people with chewing or swallowing difficulties. It is known that these diets based on traditional ground, have varying nutritional adequacy. The emergence of numerous commercial products lyophilized or ready to eat, with a wide variety of nutritional value, according to the range and recipe is concerned, represent an important step in the normalization of nutritional value and food security in people with dysphagia. This review discussed the possible advantages or disadvantages compared to traditional ground, and the possibilities of inclusion in the menu of hospitals and nursing homes. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Time-Varying Market Integration and Expected Returns in Emerging Markets

OpenAIRE

de Jong, Frank; de Roon, Frans

2001-01-01

We use a simple model in which the expected returns in emerging markets depend on their systematic risk as measured by their beta relative to the world portfolio as well as on the level of integration in that market. The level of integration is a time-varying variable that depends on the market value of the assets that can be held by domestic investors only versus the market value of the assets that can be traded freely. Our empirical analysis for 30 emerging markets shows that there are stro...

Time Varying Market Integration and Expected Rteurns in Emerging Markets

OpenAIRE

Jong, F.C.J.M. de; Roon, F.A. de

2001-01-01

We use a simple model in which the expected returns in emerging markets depend on their systematic risk as measured by their beta relative to the world portfolio as well as on the level of integration in that market.The level of integration is a time-varying variable that depends on the market value of the assets that can be held by domestic investors only versus the market value of the assets that can be traded freely.Our empirical analysis for 30 emerging markets shows that there are strong...

Supervised Learning with Complex-valued Neural Networks

CERN Document Server

Suresh, Sundaram; Savitha, Ramasamy

2013-01-01

Recent advancements in the field of telecommunications, medical imaging and signal processing deal with signals that are inherently time varying, nonlinear and complex-valued. The time varying, nonlinear characteristics of these signals can be effectively analyzed using artificial neural networks.  Furthermore, to efficiently preserve the physical characteristics of these complex-valued signals, it is important to develop complex-valued neural networks and derive their learning algorithms to represent these signals at every step of the learning process. This monograph comprises a collection of new supervised learning algorithms along with novel architectures for complex-valued neural networks. The concepts of meta-cognition equipped with a self-regulated learning have been known to be the best human learning strategy. In this monograph, the principles of meta-cognition have been introduced for complex-valued neural networks in both the batch and sequential learning modes. For applications where the computati...

Water Vapor, Temperature and Wind Profiles within Maize Canopy under in-Field Rainwater Harvesting with Wide and Narrow Runoff Strips

Directory of Open Access Journals (Sweden)

Weldemichael A. Tesfuhuney

2013-11-01

Full Text Available Micrometeorological measurements were used to evaluate heat and water vapor to describe the transpiration (Ev and soil evaporation (Es processes for wide and narrow runoff strips under in-field rainwater harvesting (IRWH system. The resulting sigmoid-shaped water vapor (ea in wide and narrow runoff strips varied in lower and upper parts of the maize canopy. In wide runoff strips, lapse conditions of ea extended from lowest measurement level (LP to the upper middle section (MU and inversion was apparent at the top of the canopy. The virtual potential temperature (θv profile showed no difference in middle section, but the lower and upper portion (UP had lower  in narrow, compared to wide, strips, and LP-UP changes of 0.6 K and 1.2 K were observed, respectively. The Ev and Es within the canopy increased the ea concentration as determined by the wind order of magnitude. The ea concentration reached peak at about 1.6 kPa at a range of wind speed value of 1.4–1.8 m∙s−1 and 2.0–2.4 m∙s−1 for wide and narrow treatments, respectively. The sparse maize canopy of the wide strips could supply more drying power of the air in response to atmospheric evaporative demand compared to narrow strips. This is due to the variation in air flow in wide and narrow runoff strips that change gradients in ea for evapotranspiration processes.

Value for money: Defining and measuring 'value' in MoD's acquisition policy of obtaining best value for money

OpenAIRE

Weiss, A.

2006-01-01

Obtaining value for money is a keystone of UK Ministry of Defence (MoD) acquisition strategy embedded in its Smart Acquisition policy. This thesis examines how best to measure the relative value of competing tender submissions for major projects. There is a comprehensive discussion of a wide range of relevant definitions and over three dozen documents are scrutinised including just some sixteen published by the Government. Commercially available models, algorithms and software are examined as...

Varying ultrasound power level to distinguish surgical instruments and tissue.

Science.gov (United States)

Ren, Hongliang; Anuraj, Banani; Dupont, Pierre E

2018-03-01

We investigate a new framework of surgical instrument detection based on power-varying ultrasound images with simple and efficient pixel-wise intensity processing. Without using complicated feature extraction methods, we identified the instrument with an estimated optimal power level and by comparing pixel values of varying transducer power level images. The proposed framework exploits the physics of ultrasound imaging system by varying the transducer power level to effectively distinguish metallic surgical instruments from tissue. This power-varying image-guidance is motivated from our observations that ultrasound imaging at different power levels exhibit different contrast enhancement capabilities between tissue and instruments in ultrasound-guided robotic beating-heart surgery. Using lower transducer power levels (ranging from 40 to 75% of the rated lowest ultrasound power levels of the two tested ultrasound scanners) can effectively suppress the strong imaging artifacts from metallic instruments and thus, can be utilized together with the images from normal transducer power levels to enhance the separability between instrument and tissue, improving intraoperative instrument tracking accuracy from the acquired noisy ultrasound volumetric images. We performed experiments in phantoms and ex vivo hearts in water tank environments. The proposed multi-level power-varying ultrasound imaging approach can identify robotic instruments of high acoustic impedance from low-signal-to-noise-ratio ultrasound images by power adjustments.

Interannual changes in δ15N values in Fucus vesiculosus L

International Nuclear Information System (INIS)

Carballeira, Carlos; Rey-Asensio, Ana; Carballeira, Alejo

2014-01-01

Highlights: • Isotopic values change along the thallus of F. vesiculosus. • δ 15 N values along the thallus are different between control and polluted sites. • δ 15 N values are temporally unstable at polluted sites. - Abstract: The natural abundance of 15 N (δ 15 N) has been widely used to detect anthropogenically derived N loads in environmental impact studies. The present study involved retrospective analysis of subsamples of Fucus vesiculosus L. collected during a period of three years (2008–2010) from two sites: a control site, within a coastal reference area, and an area affected by the effluents of a marine land-based fish farm. The isotopic signal in different subsamples of the macroalgae thalli (tissue that has grown during the same period) varied depending on the age of the tissue. Moreover, the isotopic signal decreased significantly with the age of the frond to within a certain range. The δ 15 N of F. vesiculosus is temporally unstable; therefore, measurement of the δ 15 N of macroalgal tissues does not allow reliable retrospective biomonitoring of environmental pollution. Further knowledge about the growth and other biological aspects of this species is required

How important is an apology to you? Forecasting errors in evaluating the value of apologies.

Science.gov (United States)

De Cremer, David; Pillutla, Madan M; Folmer, Chris Reinders

2011-01-01

Apologies are commonly used to deal with transgressions in relationships. Results to date, however, indicate that the positive effects of apologies vary widely, and the match between people's judgments of apologies and the true value of apologies has not been studied. Building on the affective and behavioral forecasting literature, we predicted that people would overestimate how much they value apologies in reality. Across three experimental studies, our results showed that after having been betrayed by another party (or after imagining this to be the case), people (a) rated the value of an apology much more highly when they imagined receiving an apology than when they actually received an apology and (b) displayed greater trusting behavior when they imagined receiving an apology than when they actually received an apology. These results suggest that people are prone to forecasting errors regarding the effectiveness of an apology and that they tend to overvalue the impact of receiving one.

Dietary adaptation of FADS genes in Europe varied across time and geography.

Science.gov (United States)

Ye, Kaixiong; Gao, Feng; Wang, David; Bar-Yosef, Ofer; Keinan, Alon

2017-05-26

Fatty acid desaturase (FADS) genes encode rate-limiting enzymes for the biosynthesis of omega-6 and omega-3 long-chain polyunsaturated fatty acids (LCPUFAs). This biosynthesis is essential for individuals subsisting on LCPUFA-poor diets (for example, plant-based). Positive selection on FADS genes has been reported in multiple populations, but its cause and pattern in Europeans remain unknown. Here we demonstrate, using ancient and modern DNA, that positive selection acted on the same FADS variants both before and after the advent of farming in Europe, but on opposite (that is, alternative) alleles. Recent selection in farmers also varied geographically, with the strongest signal in southern Europe. These varying selection patterns concur with anthropological evidence of varying diets, and with the association of farming-adaptive alleles with higher FADS1 expression and thus enhanced LCPUFA biosynthesis. Genome-wide association studies reveal that farming-adaptive alleles not only increase LCPUFAs, but also affect other lipid levels and protect against several inflammatory diseases.

Time Varying Market Integration and Expected Rteurns in Emerging Markets

NARCIS (Netherlands)

de Jong, F.C.J.M.; de Roon, F.A.

2001-01-01

We use a simple model in which the expected returns in emerging markets depend on their systematic risk as measured by their beta relative to the world portfolio as well as on the level of integration in that market.The level of integration is a time-varying variable that depends on the market value

The Advancement Value Chain: An Exploratory Model

Science.gov (United States)

Leonard, Edward F., III

2005-01-01

Since the introduction of the value chain concept in 1985, several varying, yet virtually similar, value chains have been developed for the business enterprise. Shifting to higher education, can a value chain be found that links together the various activities of advancement so that an institution's leaders can actually look at the philanthropic…

Process model for ammonia volatilization from anaerobic swine lagoons incorporating varying wind speeds and biogas bubbling

Science.gov (United States)

Ammonia volatilization from treatment lagoons varies widely with the total ammonia concentration, pH, temperature, suspended solids, atmospheric ammonia concentration above the water surface, and wind speed. Ammonia emissions were estimated with a process-based mechanistic model integrating ammonia ...

Mapping ecosystem services' values : Current practice and future prospects

NARCIS (Netherlands)

Schägner, Jan Philipp; Brander, Luke; Maes, Joachim; Hartje, Volkmar

Mapping of ecosystem services' (ESS) values means valuing ESS in monetary terms across a relatively large geographical area and assessing how values vary across space. Thereby, mapping of ESS values reveals additional information as compared to traditional site-specific ESS valuation, which is

Shape and Spatially-Varying Reflectance Estimation from Virtual Exemplars.

Science.gov (United States)

Hui, Zhuo; Sankaranarayanan, Aswin C

2017-10-01

This paper addresses the problem of estimating the shape of objects that exhibit spatially-varying reflectance. We assume that multiple images of the object are obtained under a fixed view-point and varying illumination, i.e., the setting of photometric stereo. At the core of our techniques is the assumption that the BRDF at each pixel lies in the non-negative span of a known BRDF dictionary. This assumption enables a per-pixel surface normal and BRDF estimation framework that is computationally tractable and requires no initialization in spite of the underlying problem being non-convex. Our estimation framework first solves for the surface normal at each pixel using a variant of example-based photometric stereo. We design an efficient multi-scale search strategy for estimating the surface normal and subsequently, refine this estimate using a gradient descent procedure. Given the surface normal estimate, we solve for the spatially-varying BRDF by constraining the BRDF at each pixel to be in the span of the BRDF dictionary; here, we use additional priors to further regularize the solution. A hallmark of our approach is that it does not require iterative optimization techniques nor the need for careful initialization, both of which are endemic to most state-of-the-art techniques. We showcase the performance of our technique on a wide range of simulated and real scenes where we outperform competing methods.

Variability in the measurement of hospital-wide mortality rates.

Science.gov (United States)

Shahian, David M; Wolf, Robert E; Iezzoni, Lisa I; Kirle, Leslie; Normand, Sharon-Lise T

2010-12-23

Several countries use hospital-wide mortality rates to evaluate the quality of hospital care, although the usefulness of this metric has been questioned. Massachusetts policymakers recently requested an assessment of methods to calculate this aggregate mortality metric for use as a measure of hospital quality. The Massachusetts Division of Health Care Finance and Policy provided four vendors with identical information on 2,528,624 discharges from Massachusetts acute care hospitals from October 1, 2004, through September 30, 2007. Vendors applied their risk-adjustment algorithms and provided predicted probabilities of in-hospital death for each discharge and for hospital-level observed and expected mortality rates. We compared the numbers and characteristics of discharges and hospitals included by each of the four methods. We also compared hospitals' standardized mortality ratios and classification of hospitals with mortality rates that were higher or lower than expected, according to each method. The proportions of discharges that were included by each method ranged from 28% to 95%, and the severity of patients' diagnoses varied widely. Because of their discharge-selection criteria, two methods calculated in-hospital mortality rates (4.0% and 5.9%) that were twice the state average (2.1%). Pairwise associations (Pearson correlation coefficients) of discharge-level predicted mortality probabilities ranged from 0.46 to 0.70. Hospital-performance categorizations varied substantially and were sometimes completely discordant. In 2006, a total of 12 of 28 hospitals that had higher-than-expected hospital-wide mortality when classified by one method had lower-than-expected mortality when classified by one or more of the other methods. Four common methods for calculating hospital-wide mortality produced substantially different results. This may have resulted from a lack of standardized national eligibility and exclusion criteria, different statistical methods, or

Performance of Traffic Noise Barriers with Varying Cross-Section

Directory of Open Access Journals (Sweden)

Sanja Grubeša

2011-05-01

Full Text Available The efficiency of noise barriers largely depends on their geometry. In this paper, the performance of noise barriers was simulated using the numerical Boundary Element Method (BEM. Traffic noise was particularly considered with its standardized noise spectrum adapted to human hearing. The cross-section of the barriers was varied with the goal of finding the optimum shape in comparison to classical rectangular barriers. The barrier performance was calculated at different receiver points for a fixed barrier height and source position. The magnitude of the insertion loss parameter was used to evaluate the performance change, both in one-third octave bands and as the broadband mean insertion loss value. The proposed barriers of varying cross-section were also compared with a typical T-shape barrier of the same height.

Osmotic potential calculations of inorganic and organic aqueous solutions over wide solute concentration levels and temperatures

Energy Technology Data Exchange (ETDEWEB)

Cochrane, T. T., E-mail: agteca@hotmail.com [AGTECA S.A., 230 Oceanbeach Road, Mount Maunganui, Tauranga 3116 (New Zealand); Cochrane, T. A., E-mail: tom.cochrane@canterbury.ac.nz [Department of Civil and Natural Resources Engineering, University of Canterbury, Private Bag 4800, Christchurch 8140 (New Zealand)

2016-01-15

Purpose: To demonstrate that the authors’ new “aqueous solution vs pure water” equation to calculate osmotic potential may be used to calculate the osmotic potentials of inorganic and organic aqueous solutions over wide ranges of solute concentrations and temperatures. Currently, the osmotic potentials of solutions used for medical purposes are calculated from equations based on the thermodynamics of the gas laws which are only accurate at low temperature and solute concentration levels. Some solutions used in medicine may need their osmotic potentials calculated more accurately to take into account solute concentrations and temperatures. Methods: The authors experimented with their new equation for calculating the osmotic potentials of inorganic and organic aqueous solutions up to and beyond body temperatures by adjusting three of its factors; (a) the volume property of pure water, (b) the number of “free” water molecules per unit volume of solution, “N{sub f},” and (c) the “t” factor expressing the cooperative structural relaxation time of pure water at given temperatures. Adequate information on the volume property of pure water at different temperatures is available in the literature. However, as little information on the relative densities of inorganic and organic solutions, respectively, at varying temperatures needed to calculate N{sub f} was available, provisional equations were formulated to approximate values. Those values together with tentative t values for different temperatures chosen from values calculated by different workers were substituted into the authors’ equation to demonstrate how osmotic potentials could be estimated over temperatures up to and beyond bodily temperatures. Results: The provisional equations formulated to calculate N{sub f}, the number of free water molecules per unit volume of inorganic and organic solute solutions, respectively, over wide concentration ranges compared well with the calculations of N{sub f

Osmotic potential calculations of inorganic and organic aqueous solutions over wide solute concentration levels and temperatures

International Nuclear Information System (INIS)

Cochrane, T. T.; Cochrane, T. A.

2016-01-01

Purpose: To demonstrate that the authors’ new “aqueous solution vs pure water” equation to calculate osmotic potential may be used to calculate the osmotic potentials of inorganic and organic aqueous solutions over wide ranges of solute concentrations and temperatures. Currently, the osmotic potentials of solutions used for medical purposes are calculated from equations based on the thermodynamics of the gas laws which are only accurate at low temperature and solute concentration levels. Some solutions used in medicine may need their osmotic potentials calculated more accurately to take into account solute concentrations and temperatures. Methods: The authors experimented with their new equation for calculating the osmotic potentials of inorganic and organic aqueous solutions up to and beyond body temperatures by adjusting three of its factors; (a) the volume property of pure water, (b) the number of “free” water molecules per unit volume of solution, “N f ,” and (c) the “t” factor expressing the cooperative structural relaxation time of pure water at given temperatures. Adequate information on the volume property of pure water at different temperatures is available in the literature. However, as little information on the relative densities of inorganic and organic solutions, respectively, at varying temperatures needed to calculate N f was available, provisional equations were formulated to approximate values. Those values together with tentative t values for different temperatures chosen from values calculated by different workers were substituted into the authors’ equation to demonstrate how osmotic potentials could be estimated over temperatures up to and beyond bodily temperatures. Results: The provisional equations formulated to calculate N f , the number of free water molecules per unit volume of inorganic and organic solute solutions, respectively, over wide concentration ranges compared well with the calculations of N f using recorded

How can facility managers add value?

DEFF Research Database (Denmark)

Jensen, Per Anker; van der Voordt, Theo

2015-01-01

Recent years have seen a growing interest in the concept of added value of facilities management (FM) and corporate real estate management (CREM), and how to attain and measure it. There is a wide variety of definitions in use, and recognition of different types of added value, such as user value...

Child-Langmuir flow with periodically varying anode voltage

International Nuclear Information System (INIS)

Rokhlenko, A.

2015-01-01

Using the Lagrangian technique, we study settled Child-Langmuir flows in a one dimensional planar diodes whose anode voltages periodically vary around given positive values. Our goal is to find analytically if the average currents in these systems can exceed the famous Child-Langmuir limit found for the stationary current a long time ago. The main result of our study is that in a periodic quasi-stationary regime the average current can be larger than the Child-Langmuir maximum even by 50% compared with its adiabatic average value. The cathode current in this case has the form of rectangular pulses which are formed by a very special triangular voltage modulation. This regime, i.e., periodicity, shape of pulses, and their amplitude, needs to be carefully chosen for the best performance

The Pisa pre-main sequence tracks and isochrones. A database covering a wide range of Z, Y, mass, and age values

Science.gov (United States)

Tognelli, E.; Prada Moroni, P. G.; Degl'Innocenti, S.

2011-09-01

Context. In recent years new observations of pre-main sequence stars (pre-MS) with Z ≤ Z⊙ have been made available. To take full advantage of the continuously growing amount of data of pre-MS stars in different environments, we need to develop updated pre-MS models for a wide range of metallicity to assign reliable ages and masses to the observed stars. Aims: We present updated evolutionary pre-MS models and isochrones for a fine grid of mass, age, metallicity, and helium values. Methods: We use a standard and well-tested stellar evolutionary code (i.e. FRANEC), that adopts outer boundary conditions from detailed and realistic atmosphere models. In this code, we incorporate additional improvements to the physical inputs related to the equation of state and the low temperature radiative opacities essential to computing low-mass stellar models. Results: We make available via internet a large database of pre-MS tracks and isochrones for a wide range of chemical compositions (Z = 0.0002-0.03), masses (M = 0.2-7.0 M⊙), and ages (1-100 Myr) for a solar-calibrated mixing length parameter α (i.e. 1.68). For each chemical composition, additional models were computed with two different mixing length values, namely α = 1.2 and 1.9. Moreover, for Z ≥ 0.008, we also provided models with two different initial deuterium abundances. The characteristics of the models have been discussed in detail and compared with other work in the literature. The main uncertainties affecting theoretical predictions have been critically discussed. Comparisons with selected data indicate that there is close agreement between theory and observation. Tracks and isochrones are available on the web at the http://astro.df.unipi.it/stellar-models/Tracks and isochrones are also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/533/A109

Comparative Analysis of Signal Intensity and Apparent Diffusion Coefficient at Varying b-values in the Brain : Diffusion Weighted-Echo Planar Image (T2 and FLAIR) Sequence

International Nuclear Information System (INIS)

Oh, Jong Kap; Im, Jung Yeol

2009-01-01

Diffusion-weighted imaging (DWI) has been demonstrated to be a practical method for the diagnosis of various brain diseases such as acute infarction, brain tumor, and white matter disease. In this study, we used two techniques to examine the average signal intensity (SI) and apparent diffusion coefficient (ADC) of the brains of patients who ranged in age from 10 to 60 years. Our results indicated that the average SI was the highest in amygdala (as derived from DWI), whereas that in the cerebrospinal fluid was the lowest. The average ADC was the highest in the cerebrospinal fluid, whereas the lowest measurement was derived from the pons. The average SI and ADC were higher in T 2 -DW-EPI than in FLAIR-DW-EPI. The higher the b-value, the smaller the average difference in both imaging techniques; the lower the b-value, the greater the average difference. Also, comparative analysis of the brains of patients who had experienced cerebral infarction showed no distinct lesion in the general MR image over time. However, there was a high SI in apparent weighted images. Analysis of other brain diseases (e.g., bleeding, acute, subacute, chronic infarction) indicated SI variance in accordance with characteristics of the two techniques. The higher the SI, the lower the ADC. Taken together, the value of SI and ADC in accordance with frequently occurring areas and various brain disease varies based on the b-value and imaging technique. Because they provide additional useful information in the diagnosis and treatment of patients with various brain diseases through signal recognition, the proper imaging technique and b-value are important for the detection and interpretation of subacute stroke and other brain diseases.

Models of quality-adjusted life years when health varies over time

DEFF Research Database (Denmark)

Hansen, Kristian Schultz; Østerdal, Lars Peter Raahave

2006-01-01

Qualityadjusted life year (QALY) models are widely used for economic evaluation in the health care sector. In the first part of the paper, we establish an overview of QALY models where health varies over time and provide a theoretical analysis of model identification and parameter estimation from...... time tradeoff (TTO) and standard gamble (SG) scores. We investigate deterministic and probabilistic models and consider five different families of discounting functions in all. The second part of the paper discusses four issues recurrently debated in the literature. This discussion includes questioning...... of these two can be used to disentangle risk aversion from discounting. We find that caution must be taken when drawing conclusions from models with chronic health states to situations where health varies over time. One notable difference is that in the former case, risk aversion may be indistinguishable from...

Response of selected binomial coefficients to varying degrees of matrix sparseness and to matrices with known data interrelationships

Science.gov (United States)

Archer, A.W.; Maples, C.G.

1989-01-01

Numerous departures from ideal relationships are revealed by Monte Carlo simulations of widely accepted binomial coefficients. For example, simulations incorporating varying levels of matrix sparseness (presence of zeros indicating lack of data) and computation of expected values reveal that not only are all common coefficients influenced by zero data, but also that some coefficients do not discriminate between sparse or dense matrices (few zero data). Such coefficients computationally merge mutually shared and mutually absent information and do not exploit all the information incorporated within the standard 2 ?? 2 contingency table; therefore, the commonly used formulae for such coefficients are more complicated than the actual range of values produced. Other coefficients do differentiate between mutual presences and absences; however, a number of these coefficients do not demonstrate a linear relationship to matrix sparseness. Finally, simulations using nonrandom matrices with known degrees of row-by-row similarities signify that several coefficients either do not display a reasonable range of values or are nonlinear with respect to known relationships within the data. Analyses with nonrandom matrices yield clues as to the utility of certain coefficients for specific applications. For example, coefficients such as Jaccard, Dice, and Baroni-Urbani and Buser are useful if correction of sparseness is desired, whereas the Russell-Rao coefficient is useful when sparseness correction is not desired. ?? 1989 International Association for Mathematical Geology.

The value of space

DEFF Research Database (Denmark)

Panduro, Toke Emil

The thesis consists of four papers which address the potential and challenges of the hedonic house price method. The aim of the thesis has been to estimate consistent and efficient parameter estimates of spatial varying regressors in the hedonic house price model. In particular, the articles are ...... and provide reliable estimates of the value of different types of green space....... are concerned with the value of different types of green space and how these values can be applied in urban planning policies related to climate adaption. The results presented in this thesis, ensure a “level playing field” in the assessment of the cost and benefits of different climate adaptation strategies...

Tolerable Time-Varying Overflow on Grass-Covered Slopes

Directory of Open Access Journals (Sweden)

Steven A. Hughes

2015-03-01

Full Text Available Engineers require estimates of tolerable overtopping limits for grass-covered levees, dikes, and embankments that might experience steady overflow. Realistic tolerance estimates can be used for both resilient design and risk assessment. A simple framework is developed for estimating tolerable overtopping on grass-covered slopes caused by slowly-varying (in time overtopping discharge (e.g., events like storm surges or river flood waves. The framework adapts the well-known Hewlett curves of tolerable limiting velocity as a function of overflow duration. It has been hypothesized that the form of the Hewlett curves suggests that the grass erosion process is governed by the flow work on the slope above a critical threshold velocity (referred to as excess work, and the tolerable erosional limit is reached when the cumulative excess work exceeds a given value determined from the time-dependent Hewlett curves. The cumulative excess work is expressed in terms of overflow discharge above a critical discharge that slowly varies in time, similar to a discharge hydrograph. The methodology is easily applied using forecast storm surge hydrographs at specific locations where wave action is minimal. For preliminary planning purposes, when storm surge hydrographs are unavailable, hypothetical equations for the water level and overflow discharge hydrographs are proposed in terms of the values at maximum overflow and the total duration of overflow. An example application is given to illustrate use of the methodology.

Average Costs versus Net Present Value

NARCIS (Netherlands)

E.A. van der Laan (Erwin); R.H. Teunter (Ruud)

2000-01-01

textabstractWhile the net present value (NPV) approach is widely accepted as the right framework for studying production and inventory control systems, average cost (AC) models are more widely used. For the well known EOQ model it can be verified that (under certain conditions) the AC approach gives

What Is the Value of Value-Based Purchasing?

Science.gov (United States)

Tanenbaum, Sandra J

2016-10-01

Value-based purchasing (VBP) is a widely favored strategy for improving the US health care system. The meaning of value that predominates in VBP schemes is (1) conformance to selected process and/or outcome metrics, and sometimes (2) such conformance at the lowest possible cost. In other words, VBP schemes choose some number of "quality indicators" and financially incent providers to meet them (and not others). Process measures are usually based on clinical science that cannot determine the effects of a process on individual patients or patients with comorbidities, and do not necessarily measure effects that patients value; additionally, there is no provision for different patients valuing different things. Proximate outcome measures may or may not predict distal ones, and the more distal the outcome, the less reliably it can be attributed to health care. Outcome measures may be quite rudimentary, such as mortality rates, or highly contestable: survival or function after prostate surgery? When cost is an element of value-based purchasing, it is the cost to the value-based payer and not to other payers or patients' families. The greatest value of value-based purchasing may not be to patients or even payers, but to policy makers seeking a morally justifiable alternative to politically contested regulatory policies. Copyright © 2016 by Duke University Press.

Smoothly varying in-plane stiffness heterogeneity evaluated under uniaxial tensile stress

Science.gov (United States)

J.M. Considine; F. Pierron; K.T. Turner; P. Lava; X. Tang

2017-01-01

Identification of spatially varying stiffness is a challenging, but important, research topic in the mechanics of materials and can provide the necessary information for material suitability, damage, and process control, especially for high‐value applications. One homogeneous and 3 heterogeneous virtual field method (VFM) formulations were used to create a methodology...

Adaptive Value Normalization in the Prefrontal Cortex Is Reduced by Memory Load

Science.gov (United States)

Burke, C. J.; Seifritz, E.; Tobler, P. N.

2017-01-01

Abstract Adaptation facilitates neural representation of a wide range of diverse inputs, including reward values. Adaptive value coding typically relies on contextual information either obtained from the environment or retrieved from and maintained in memory. However, it is unknown whether having to retrieve and maintain context information modulates the brain’s capacity for value adaptation. To address this issue, we measured hemodynamic responses of the prefrontal cortex (PFC) in two studies on risky decision-making. In each trial, healthy human subjects chose between a risky and a safe alternative; half of the participants had to remember the risky alternatives, whereas for the other half they were presented visually. The value of safe alternatives varied across trials. PFC responses adapted to contextual risk information, with steeper coding of safe alternative value in lower-risk contexts. Importantly, this adaptation depended on working memory load, such that response functions relating PFC activity to safe values were steeper with presented versus remembered risk. An independent second study replicated the findings of the first study and showed that similar slope reductions also arose when memory maintenance demands were increased with a secondary working memory task. Formal model comparison showed that a divisive normalization model fitted effects of both risk context and working memory demands on PFC activity better than alternative models of value adaptation, and revealed that reduced suppression of background activity was the critical parameter impairing normalization with increased memory maintenance demand. Our findings suggest that mnemonic processes can constrain normalization of neural value representations. PMID:28462394

The propagation of varied timescale perturbations in landscapes

Science.gov (United States)

Bingham, N.; Johnson, K. N.; Bookhagen, B.; Chadwick, O.

2016-12-01

The classic assumption of steady-state landscapes greatly simplifies models of earth-surface processes. Theoretically, steady-state denotes time independence, but in real landscapes steady-state requires a timescale over which to assume (or document) no change. In the past, poor spatiotemporal resolution of eroding landscapes necessitated that shorter timescale perturbations be ignored in favor of regional formulations of rock uplift = erosion, 105, 6 years. Now, novel techniques and technologies provide an opportunity to define local landscape response to various timescales of perturbations; thus, allowing us to consider multiple steady-states on adjacent watersheds or even along a single watershed. This study seeks to identify the physical propagation of varied timescale perturbations in landscapes in order to provide an updated geomorphic context for interpreting critical zone processes. At our study site - Santa Cruz Island (SCI), CA - perturbations include sea level and climate fluctuations over 105 years coupled with pulses of overgrazing and extreme storm events during the last 200 years. Comprehensive knickpoint location maps and dated marine and fill terraces tighten the spatiotemporal constraints on erosion for SCI. In addition, the island hosts a wide range of lithologies, allowing us to compare lithologic effects on landscape response to perturbations. Our study uses lidar point clouds and high resolution (0.25 and 1 m) digital elevation model analysis to segment landscapes by the degree of their response to perturbations. Landscape response is measured by increases in topographic roughness. We ascertain roughness by analyzing the changes in different terrain attributes on multiple spatial scales: catchment, sub-catchments and individual hillslopes. Terrain attributes utilized include slope, curvature, local relief, flowpath length and contributing catchment area. Statistical analysis of these properties indicates narrower ranges in values for regions

Revisiting enduring values

Directory of Open Access Journals (Sweden)

Michael Gorman

2015-05-01

Full Text Available The paper discusses the nature of values in general and the nature and utility of the values of librarianship.  Delineates the changes that have occurred and are occurring in the wider world and the nature of change; also the importance of values in providing a framework for dealing with present and future change.  Stresses the centrality of the human record to societal progress, the place of the human record in cultural heritage, and the central purpose of libraries in facilitating interaction with the human record and furthering the transmission of cultural heritage.  Urges a turning away from the alien value systems of information technology, consumerism, materialism, and corporate management, and a consequent set of alliances between libraries and a wide range of cultural institutions and associations.

Comparative Analysis of Signal Intensity and Apparent Diffusion Coefficient at Varying b-values in the Brain : Diffusion Weighted-Echo Planar Image (T{sub 2} and FLAIR) Sequence

Energy Technology Data Exchange (ETDEWEB)

Oh, Jong Kap [Dept. of Radiology, Cheomdan Medical Center, Gwangju (Korea, Republic of); Im, Jung Yeol [Dept. of Digital Management Information Graduate School of Nambu Univesity, Gwangju (Korea, Republic of)

2009-09-15

Diffusion-weighted imaging (DWI) has been demonstrated to be a practical method for the diagnosis of various brain diseases such as acute infarction, brain tumor, and white matter disease. In this study, we used two techniques to examine the average signal intensity (SI) and apparent diffusion coefficient (ADC) of the brains of patients who ranged in age from 10 to 60 years. Our results indicated that the average SI was the highest in amygdala (as derived from DWI), whereas that in the cerebrospinal fluid was the lowest. The average ADC was the highest in the cerebrospinal fluid, whereas the lowest measurement was derived from the pons. The average SI and ADC were higher in T{sub 2}-DW-EPI than in FLAIR-DW-EPI. The higher the b-value, the smaller the average difference in both imaging techniques; the lower the b-value, the greater the average difference. Also, comparative analysis of the brains of patients who had experienced cerebral infarction showed no distinct lesion in the general MR image over time. However, there was a high SI in apparent weighted images. Analysis of other brain diseases (e.g., bleeding, acute, subacute, chronic infarction) indicated SI variance in accordance with characteristics of the two techniques. The higher the SI, the lower the ADC. Taken together, the value of SI and ADC in accordance with frequently occurring areas and various brain disease varies based on the b-value and imaging technique. Because they provide additional useful information in the diagnosis and treatment of patients with various brain diseases through signal recognition, the proper imaging technique and b-value are important for the detection and interpretation of subacute stroke and other brain diseases.

Nonlinear control of linear parameter varying systems with applications to hypersonic vehicles

Science.gov (United States)

Wilcox, Zachary Donald

The focus of this dissertation is to design a controller for linear parameter varying (LPV) systems, apply it specifically to air-breathing hypersonic vehicles, and examine the interplay between control performance and the structural dynamics design. Specifically a Lyapunov-based continuous robust controller is developed that yields exponential tracking of a reference model, despite the presence of bounded, nonvanishing disturbances. The hypersonic vehicle has time varying parameters, specifically temperature profiles, and its dynamics can be reduced to an LPV system with additive disturbances. Since the HSV can be modeled as an LPV system the proposed control design is directly applicable. The control performance is directly examined through simulations. A wide variety of applications exist that can be effectively modeled as LPV systems. In particular, flight systems have historically been modeled as LPV systems and associated control tools have been applied such as gain-scheduling, linear matrix inequalities (LMIs), linear fractional transformations (LFT), and mu-types. However, as the type of flight environments and trajectories become more demanding, the traditional LPV controllers may no longer be sufficient. In particular, hypersonic flight vehicles (HSVs) present an inherently difficult problem because of the nonlinear aerothermoelastic coupling effects in the dynamics. HSV flight conditions produce temperature variations that can alter both the structural dynamics and flight dynamics. Starting with the full nonlinear dynamics, the aerothermoelastic effects are modeled by a temperature dependent, parameter varying state-space representation with added disturbances. The model includes an uncertain parameter varying state matrix, an uncertain parameter varying non-square (column deficient) input matrix, and an additive bounded disturbance. In this dissertation, a robust dynamic controller is formulated for a uncertain and disturbed LPV system. The developed

The value of electricity distribution networks

International Nuclear Information System (INIS)

De Paoli, L.

2000-01-01

This article presents the results of a study aimed at evaluating parts of the distribution network of ENEL, in charge of distributing and supplying electricity to its captive market, that could be sold as a separate entity. To determine the asset value of these hypothetical companies, the discounted cash flow method has been used applied to the 147 ENEL's distributing zones. The econometric analysis shows that the relevant variables are the quantity sold to non residential and non big industrial consumers and the length of medium voltage lines. According to the available data and to the methodology chosen, the per client value of the distribution zones of ENEL varies substantially. The maximum value is bout three times the mean value and the minimum value is largely negative. The article maintains that changes in regulation could greatly modify the asset value of distribution networks. The main regulatory risks are linked to the degree of market opening, the introduction of compensation mechanisms between different distributors and the allowed maximum revenue fixed by energy Authority for a given period of time. This point is developed in the appendix where it is shown that the price cap method is decided on the basis of a rate of return which is valid at the moment of the cap fixing but that could be no longer valid if the rate of inflation varies [it

ΔT and tidal acceleration values from three european medieval eclipses

Science.gov (United States)

Martinez, M. J.; Marco, F. J.

2011-10-01

There are many possible reasons for the fact that the rate of rotation of the Earth is slowly decreasing in time, being the most important the tidal friction. Since Universal Time (UT) is a time scale based on the rotation of the Earth and ΔT defined as the difference between the uniform time-scale (Dynamical Time), and the Universal Time, clearly that ΔT will vary with time. The problem is that this variation is not uniform, existing irregular fluctuations. In addition, it is not possible to predict exact values for ΔT, being the only possibility its deduction a posteriori from observations. ΔT is strongly related with occultations and eclipses, because it is used for the calculation of exact times of the event, and for determining the position of the central line or the zone of visibility. In this sense, a value ΔT =3600s is roughly equivalent to a shift of 15. in longitude. Past values of ΔT can be deduced from historical astronomical observations such as ancient eclipses which have been widely studied by F.R. Stephenson [3] and [4] who has even obtained an approximation fitted with cubic splines for ΔT from -500 to +1950. This approximation is nowadays widely used in astronomical calculations. The derived relative error from ΔT obtained from ancient eclipsed is quite large, mainly because of the large width of the totality zone and the inaccuracy in the definition of the observational place. A possibility to partially solve these former problems is the analysis of total eclipse records from multiple sites, which could provide a narrow parameter range. In addition, The conjunct analysis of these astronomical phenomena is useful for determining a range of ΔT in function of the tidal acceleration of the Moon. Further discussion about these eclipses in under review.

Pinning, de-pinning and re-pinning of a slowly varying rivulet

KAUST Repository

Paterson, C.; Wilson, S.K.; Duffy, B.R.

2013-01-01

The solutions for the unidirectional flow of a thin rivulet with prescribed volume flux down an inclined planar substrate are used to describe the locally unidirectional flow of a rivulet with constant width (i.e. pinned contact lines) but slowly varying contact angle as well as the possible pinning and subsequent de-pinning of a rivulet with constant contact angle and the possible de-pinning and subsequent re-pinning of a rivulet with constant width as they flow in the azimuthal direction from the top to the bottom of a large horizontal cylinder. Despite being the same locally, the global behaviour of a rivulet with constant width can be very different from that of a rivulet with constant contact angle. In particular, while a rivulet with constant non-zero contact angle can always run from the top to the bottom of the cylinder, the behaviour of a rivulet with constant width depends on the value of the width. Specifically, while a narrow rivulet can run all the way from the top to the bottom of the cylinder, a wide rivulet can run from the top of the cylinder only to a critical azimuthal angle. The scenario in which the hitherto pinned contact lines of the rivulet de-pin at the critical azimuthal angle and the rivulet runs from the critical azimuthal angle to the bottom of the cylinder with zero contact angle but slowly varying width is discussed. The pinning and de-pinning of a rivulet with constant contact angle, and the corresponding situation involving the de-pinning and re-pinning of a rivulet with constant width at a non-zero contact angle which generalises the de-pinning at zero contact angle discussed earlier, are described. In the latter situation, the mass of fluid on the cylinder is found to be a monotonically increasing function of the constant width. © 2013 Elsevier Masson SAS. All rights reserved.

Pinning, de-pinning and re-pinning of a slowly varying rivulet

KAUST Repository

Paterson, C.

2013-09-01

The solutions for the unidirectional flow of a thin rivulet with prescribed volume flux down an inclined planar substrate are used to describe the locally unidirectional flow of a rivulet with constant width (i.e. pinned contact lines) but slowly varying contact angle as well as the possible pinning and subsequent de-pinning of a rivulet with constant contact angle and the possible de-pinning and subsequent re-pinning of a rivulet with constant width as they flow in the azimuthal direction from the top to the bottom of a large horizontal cylinder. Despite being the same locally, the global behaviour of a rivulet with constant width can be very different from that of a rivulet with constant contact angle. In particular, while a rivulet with constant non-zero contact angle can always run from the top to the bottom of the cylinder, the behaviour of a rivulet with constant width depends on the value of the width. Specifically, while a narrow rivulet can run all the way from the top to the bottom of the cylinder, a wide rivulet can run from the top of the cylinder only to a critical azimuthal angle. The scenario in which the hitherto pinned contact lines of the rivulet de-pin at the critical azimuthal angle and the rivulet runs from the critical azimuthal angle to the bottom of the cylinder with zero contact angle but slowly varying width is discussed. The pinning and de-pinning of a rivulet with constant contact angle, and the corresponding situation involving the de-pinning and re-pinning of a rivulet with constant width at a non-zero contact angle which generalises the de-pinning at zero contact angle discussed earlier, are described. In the latter situation, the mass of fluid on the cylinder is found to be a monotonically increasing function of the constant width. © 2013 Elsevier Masson SAS. All rights reserved.

Time-Varying Periodicity in Intraday Volatility

DEFF Research Database (Denmark)

Andersen, Torben Gustav; Thyrsgaard, Martin; Todorov, Viktor

We develop a nonparametric test for deciding whether return volatility exhibits time-varying intraday periodicity using a long time-series of high-frequency data. Our null hypothesis, commonly adopted in work on volatility modeling, is that volatility follows a stationary process combined...... with a constant time-of-day periodic component. We first construct time-of-day volatility estimates and studentize the high-frequency returns with these periodic components. If the intraday volatility periodicity is invariant over time, then the distribution of the studentized returns should be identical across...... with estimating volatility moments through their sample counterparts. Critical values are computed via easy-to-implement simulation. In an empirical application to S&P 500 index returns, we find strong evidence for variation in the intraday volatility pattern driven in part by the current level of volatility...

Computing Conditional VaR using Time-varying CopulasComputing Conditional VaR using Time-varying Copulas

Directory of Open Access Journals (Sweden)

Beatriz Vaz de Melo Mendes

2005-12-01

Full Text Available It is now widespread the use of Value-at-Risk (VaR as a canonical measure at risk. Most accurate VaR measures make use of some volatility model such as GARCH-type models. However, the pattern of volatility dynamic of a portfolio follows from the (univariate behavior of the risk assets, as well as from the type and strength of the associations among them. Moreover, the dependence structure among the components may change conditionally t past observations. Some papers have attempted to model this characteristic by assuming a multivariate GARCH model, or by considering the conditional correlation coefficient, or by incorporating some possibility for switches in regimes. In this paper we address this problem using time-varying copulas. Our modeling strategy allows for the margins to follow some FIGARCH type model while the copula dependence structure changes over time.

Estimation of the value-at-risk parameter: Econometric analysis and the extreme value theory approach

Directory of Open Access Journals (Sweden)

Mladenović Zorica

2006-01-01

Full Text Available In this paper different aspects of value-at-risk estimation are considered. Daily returns of CISCO, INTEL and NASDAQ stock indices are analyzed for period: September 1996 - September 2006. Methods that incorporate time varying variability and heavy tails of the empirical distributions of returns are implemented. The main finding of the paper is that standard econometric methods underestimate the value-at-risk parameter if heavy tails of the empirical distribution are not explicitly taken into account. .

Tariff based value of wind energy

Energy Technology Data Exchange (ETDEWEB)

Raekkoelaeinen, J; Vilkko, M; Antila, H; Lautala, P [Tampere Univ. of Technology (Finland)

1996-12-31

In this article an approach for determining a value of wind energy is presented. Calculation is based on wholesale tariffs, i.e. the value of wind energy is defined in comparison with other purchase. This approach can be utilised as an aid in the investment planning in defining the benefits of new wind generation capacity. Linear programming optimization method is used. A case study is presented for different wind scenarios. The value of wind energy can vary remarkably depending on timing of power output. (author)

Tariff based value of wind energy

Energy Technology Data Exchange (ETDEWEB)

Raekkoelaeinen, J.; Vilkko, M.; Antila, H.; Lautala, P. [Tampere Univ. of Technology (Finland)

1995-12-31

In this article an approach for determining a value of wind energy is presented. Calculation is based on wholesale tariffs, i.e. the value of wind energy is defined in comparison with other purchase. This approach can be utilised as an aid in the investment planning in defining the benefits of new wind generation capacity. Linear programming optimization method is used. A case study is presented for different wind scenarios. The value of wind energy can vary remarkably depending on timing of power output. (author)

Jetfighter: An Experiential Value Chain Exercise

Science.gov (United States)

Sheehan, Norman T.; Gamble, Edward N.

2010-01-01

Value chain analysis is widely taught in business schools and applied by practitioners to improve business performance. Despite its ubiquity, many students struggle to understand and apply value chain concepts in practice. JetFighter uses a complex manufacturing process (making intricate paper planes) to provide students an opportunity to enhance…

Microsatellites in varied arenas of research

Directory of Open Access Journals (Sweden)

K S Remya

2010-01-01

Full Text Available Microsatellites known as simple-sequence repeats (SSRs or short-tandem repeats (STRs, represent specific sequences of DNA consisting of tandemly repeated units of one to six nucleotides. The repetitive nature of microsatellites makes them particularly prone to grow or shrink in length and these changes can have both good and bad consequences for the organisms that possess them. They are responsible for various neurological diseases and hence the same cause is now utilized for the early detection of various diseases, such as, Schizophrenia and Bipolar Disorder, Congenital generalized Hypertrichosis, Asthma, and Bronchial Hyperresponsiveness. These agents are widely used for forensic identification and relatedness testing, and are predominant genetic markers in this area of application. The application of microsatellites is an extending web and covers the varied scenarios of science, such as, conservation biology, plant genetics, and population studies. At present, researches are progressing round the globe to extend the use of these genetic repeaters to unmask the hidden genetic secrets behind the creation of the world.

Mapping Ecosystem Services’ Values: Current Practice and Future Prospects

OpenAIRE

Jan Philipp Schägner; Luke Brander; Joachim Maes; Volkmar Hartje

2012-01-01

Mapping of ecosystem services' (ESS) values means valuing ESS in monetary terms across a relatively large geographical area and assessing how values vary across space. Thereby, mapping of ESS values reveals additional information as compared to traditional site-specific ESS valuation, which is beneficial for designing land use policies for maintaining ESS supply. Since the well-known article by Costanza et al. (1997), who mapped global ESS values, the number of publications mapping ESS values...

Diagnostic value of different tumor markers, our experience

International Nuclear Information System (INIS)

Pervez, T.; Anwar, S.

2000-01-01

Variety of tumor markers with varying sensitivity and specificity are used for diagnosis of different malignancies. This study was done to determine the diagnostic value of different tumor markers in our patients with various malignancies. Out of 235 patients studied, 162 were suffering from malignant and 73 from benign diseases. Among these 84 were positive for tumor markers. Out of these positive tumor markers, 75 were suffering from malignancy. Tumor marker analyzed were ca-15-3, ca-125, BETA-HCG, CEA, PSA and alpha-FP depending upon the type of the disease these cases presented. Analysis of the results revealed that different tumor markers had sensitivity varying from 76.9-95.8% and specificity varying form 75-90.9%. CA-125 was observed to be the most specific and sensitive tumor marker for ovarian tumors followed by alpha-FP for hepatocellular tumors and CEA for gastrointestinal tumors. Similarly, PSA for prostate cancers, beta-HCG for choriocarcinoma and CA-15-3 for breast cancer. It is concluded that all the tumor markers have a variable diagnostic value, which cannot be relied upon independently, without other tests added to increase diagnostic value. (author)

Wide area stability analysis and control of interconnected power systems with HVDC and FACTS devices

Energy Technology Data Exchange (ETDEWEB)

Li, Yong

2012-11-01

In order to damp low-frequency oscillations and improve the overall stability of large-scale interconnected power systems, this book investigates the wide-area stability analysis and control methods from different perspectives. The flexible and fast control capability of high-voltage (FACTS) is investigated in detail to implement a wide-area measurement based damping control. A sequential and global mixed optimization method is proposed to simultaneously optimize local and wide area damping controllers. A wide-area robust coordination method is presented to coordinate multiple wide-area damping controllers (WADC). A delay-dependent robust design method is also proposed to handle time-varying delays commonly existing in wide-area signal communication. A closed-loop hardware experiment is used to validate the damping performance. The research activities of this book include power system stability analysis and control, wide-area damping control as well as HVDC and FACTS technologies.

Robust stability analysis of large power systems using the structured singular value theory

Energy Technology Data Exchange (ETDEWEB)

Castellanos, R.; Sarmiento, H. [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Messina, A.R. [Cinvestav, Graduate Program in Electrical Engineering, Guadalajara, Jalisco (Mexico)

2005-07-01

This paper examines the application of structured singular value (SSV) theory to analyse robust stability of complex power systems with respect to a set of structured uncertainties. Based on SSV theory and the frequency sweep method, techniques for robust analysis of large-scale power systems are developed. The main interest is focused on determining robust stability for varying operating conditions and uncertainties in the structure of the power system. The applicability of the proposed techniques is verified through simulation studies on a large-scale power system. In particular, results for the system are considered for a wide range of uncertainties of operating conditions. Specifically, the developed technique is used to estimate the effect of variations in the parameters of a major system inter-tie on the nominal stability of a critical inter-area mode. (Author)

Hybrid value foraging: How the value of targets shapes human foraging behavior.

Science.gov (United States)

Wolfe, Jeremy M; Cain, Matthew S; Alaoui-Soce, Abla

2018-04-01

In hybrid foraging, observers search visual displays for multiple instances of multiple target types. In previous hybrid foraging experiments, although there were multiple types of target, all instances of all targets had the same value. Under such conditions, behavior was well described by the marginal value theorem (MVT). Foragers left the current "patch" for the next patch when the instantaneous rate of collection dropped below their average rate of collection. An observer's specific target selections were shaped by previous target selections. Observers were biased toward picking another instance of the same target. In the present work, observers forage for instances of four target types whose value and prevalence can vary. If value is kept constant and prevalence manipulated, participants consistently show a preference for the most common targets. Patch-leaving behavior follows MVT. When value is manipulated, observers favor more valuable targets, though individual foraging strategies become more diverse, with some observers favoring the most valuable target types very strongly, sometimes moving to the next patch without collecting any of the less valuable targets.

A Critique of Values: Clarification in Drug Education.

Science.gov (United States)

Chng, Chwee Lye

1980-01-01

Values clarification is widely used in drug education programs. Criticisms are offered on the role of content in valuing, the position of ethical relativism, the danger of indoctrination, and the social pressure to conform. (Author)

Big bang nucleosynthesis with a varying fine structure constant and nonstandard expansion rate

International Nuclear Information System (INIS)

Ichikawa, Kazuhide; Kawasaki, Masahiro

2004-01-01

We calculate the primordial abundances of light elements produced during big bang nucleosynthesis when the fine structure constant and/or the cosmic expansion rate take nonstandard values. We compare them with the recent values of observed D, 4 He, and 7 Li abundances, which show a slight inconsistency among themselves in the standard big bang nucleosynthesis scenario. This inconsistency is not solved by considering either a varying fine structure constant or a nonstandard expansion rate separately but solutions are found by their simultaneous existence

Taking Stock of Project Value Creation

DEFF Research Database (Denmark)

Laursen, Markus; Svejvig, Per

2014-01-01

This paper presents the outcome of a literature review through classifying and analyzing 59 publications in project value creation literature. The analysis led to five distinct categories: Benefit Realization Management (BRM) and techniques, broad value perspective, value time frame, engineering...... requirements and product development. These five categories cover a wide selection of value creation literature in project contexts. The project types reported in empirical studies are mainly IS/IT and construction and a variety of other types such as R&D and strategy implementation. The literature dates back...

Hepatopancreaticobiliary Values after Thoracoabdominal Aneurysm Repair

Science.gov (United States)

Wu, Darrell; Coselli, Joseph S.; Johnson, Michael L.; LeMaire, Scott A.

2014-01-01

Background: After thoracoabdominal aortic aneurysm (TAAA) repair, blood tests assessing hepatopancreaticobiliary (HPB) organs commonly have abnormal results. The clinical significance of such abnormalities is difficult to determine because the expected postoperative levels have not been characterized. Therefore, we sought to establish expected trends in HPB laboratory values after TAAA repair. Methods: This 5-year study comprised 155 patients undergoing elective Crawford extent II TAAA repair. In accordance with a prospective study protocol, all repairs involved left-sided heart bypass, selective visceral perfusion, and cold renal perfusion. Blood levels of aspartate transaminase (AST), alanine transaminase (ALT), γ-glutamyl transpeptidase (GGT), lactate dehydrogenase (LDH), total bilirubin, amylase, and lipase were measured before TAAA repair and for 7 days afterward. Ratios between postoperative and baseline levels were compared for each time point with 95% confidence intervals. Results: Temporal patterns for the laboratory values varied greatly. Amylase, lipase, and AST underwent significant early increases before decreasing to preoperative levels. LDH increased immediately and remained significantly elevated, whereas ALT increased more gradually. GGT remained near baseline through postoperative day 4, and then increased to more than twice baseline. Total bilirubin never differed significantly from baseline. After adjusted analysis, the ischemic time predicted the maximum AST, lipase, GGT, and LDH values. Conclusions: Although most HPB laboratory values increase significantly after elective TAAA repair, the temporal trends for different values vary substantially. The ischemic time predicts the maximum AST, lipase, GGT, and LDH levels. These trends should be considered when laboratory values are assessed after TAAA repair. PMID:26798731

How to derive biological information from the value of the normalization constant in allometric equations.

Science.gov (United States)

Kaitaniemi, Pekka

2008-04-09

Allometric equations are widely used in many branches of biological science. The potential information content of the normalization constant b in allometric equations of the form Y = bX(a) has, however, remained largely neglected. To demonstrate the potential for utilizing this information, I generated a large number of artificial datasets that resembled those that are frequently encountered in biological studies, i.e., relatively small samples including measurement error or uncontrolled variation. The value of X was allowed to vary randomly within the limits describing different data ranges, and a was set to a fixed theoretical value. The constant b was set to a range of values describing the effect of a continuous environmental variable. In addition, a normally distributed random error was added to the values of both X and Y. Two different approaches were then used to model the data. The traditional approach estimated both a and b using a regression model, whereas an alternative approach set the exponent a at its theoretical value and only estimated the value of b. Both approaches produced virtually the same model fit with less than 0.3% difference in the coefficient of determination. Only the alternative approach was able to precisely reproduce the effect of the environmental variable, which was largely lost among noise variation when using the traditional approach. The results show how the value of b can be used as a source of valuable biological information if an appropriate regression model is selected.

Expectancy-Value Theory in Persistence of Learning Effects in Schizophrenia: Role of Task Value and Perceived Competency

OpenAIRE

Choi, Jimmy; Fiszdon, Joanna M.; Medalia, Alice

2010-01-01

Expectancy-value theory, a widely accepted model of motivation, posits that expectations of success on a learning task and the individual value placed on the task are central determinants of motivation to learn. This is supported by research in healthy controls suggesting that beliefs of self-and-content mastery can be so influential they can predict the degree of improvement on challenging cognitive tasks even more so than general cognitive ability. We examined components of expectancy-value...

Decreased value-sensitivity in schizophrenia.

Science.gov (United States)

Martinelli, Cristina; Rigoli, Francesco; Dolan, Ray J; Shergill, Sukhwinder S

2018-01-01

Pathophysiology in schizophrenia has been linked to aberrant incentive salience, namely the dysfunctional processing of value linked to abnormal dopaminergic activity. In line with this, recent studies showed impaired learning of value in schizophrenia. However, how value is used to guide behaviour independently from learning, as in risky choice, has rarely been examined in this disorder. We studied value-guided choice under risk in patients with schizophrenia and in controls using a task requiring a choice between a certain monetary reward, varying trial-by-trial, and a gamble offering an equal probability of getting double this certain amount or nothing. We observed that patients compared to controls exhibited reduced sensitivity to values, implying that their choices failed to flexibly adapt to the specific values on offer. Moreover, the degree of this value sensitivity inversely correlated with aberrant salience experience, suggesting that the inability to tune choice to value may be a key element of aberrant salience in the illness. Our results help clarify the cognitive mechanisms underlying improper attribution of value in schizophrenia and may thus inform cognitive interventions aimed at reinstating value sensitivity in patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of exercise on the formation of life-wide and value orientations of university students.

OpenAIRE

Marchenko O.U.

2011-01-01

In this paper we consider the common interests of the students responsible for their hobbies in their spare time and the formation of values of individual physical education students as a basis for self-motivation. In the experiment participated 70 students. Classes are held during the school year in the amount of 4 hours per week. Determined the level of impact studies on the structure and hierarchy of values of students.

Assessment of Motor Control during Three-Dimensional Movements Tracking with Position-Varying Gravity Compensation

Directory of Open Access Journals (Sweden)

Yao Huang

2017-05-01

Full Text Available Active movements are important in the rehabilitation training for patients with neurological motor disorders, while weight of upper limb impedes movements due to muscles weakness. The objective of this study is to develop a position-varying gravity compensation strategy for a cable-based rehabilitation robot. The control strategy can estimate real-time gravity torque according to position feedback. Then, the performance of this control strategy was compared with the other two kinds of gravity compensation strategies (i.e., without compensation and with fixed compensation during movements tracking. Seven healthy subjects were invited to conduct tracking tasks along four different directions (i.e., upward, forward, leftward, and rightward. The performance of movements with different compensation strategies was compared in terms of root mean square error (RMSE between target and actual moving trajectories, normalized jerk score (NJS, mean velocity ratio (MVR of main motion direction, and the activation of six muscles. The results showed that there were significant effects in control strategies in all four directions with the RMSE and NJS values in the following order: without compensation > fixed compensation > position-varying compensation and MVR values in the following order: without compensation < fixed compensation < position-varying compensation (p < 0.05. Comparing with movements without compensation in all four directions, the activation of muscles during movements with position-varying compensation showed significant reductions, except the activations of triceps and in forward and leftward movements, the activations of upper trapezius and middle parts of deltoid in upward movements and the activations of posterior parts of deltoid in all four directions (p < 0.05. Therefore, with position-varying gravity compensation, the upper limb cable-based rehabilitation robotic system might assist subjects to perform movements with higher quality and

Wide-angle full-vector beam propagation method based on an alternating direction implicit preconditioner

Science.gov (United States)

Chui, Siu Lit; Lu, Ya Yan

2004-03-01

Wide-angle full-vector beam propagation methods (BPMs) for three-dimensional wave-guiding structures can be derived on the basis of rational approximants of a square root operator or its exponential (i.e., the one-way propagator). While the less accurate BPM based on the slowly varying envelope approximation can be efficiently solved by the alternating direction implicit (ADI) method, the wide-angle variants involve linear systems that are more difficult to handle. We present an efficient solver for these linear systems that is based on a Krylov subspace method with an ADI preconditioner. The resulting wide-angle full-vector BPM is used to simulate the propagation of wave fields in a Y branch and a taper.

Community and patient values for preventing herpes zoster.

Science.gov (United States)

Lieu, Tracy A; Ortega-Sanchez, Ismael; Ray, G Thomas; Rusinak, Donna; Yih, W Katherine; Choo, Peter W; Shui, Irene; Kleinman, Ken; Harpaz, Rafael; Prosser, Lisa A

2008-01-01

The US Advisory Committee on Immunization Practices has recently recommended a new vaccine against herpes zoster (shingles) for routine use in adults aged > or =60 years. However, estimates of the cost effectiveness of this vaccine vary widely, in part because of gaps in the data on the value of preventing herpes zoster. Our aims were to (i) generate comprehensive information on the value of preventing a range of outcomes of herpes zoster; (ii) compare these values among community members and patients with shingles and post-herpetic neuralgia (PHN); and (iii) identify clinical and demographic characteristics that explain the variation in these values. Community members drawn from a nationally representative survey research panel (n = 527) completed an Internet-based survey using time trade-off and willingness-to-pay questions to value a series of scenarios that described cases of herpes zoster with varying pain intensities (on a scale of 0 to 10, where 0 represents no pain and 10 represents the worst imaginable pain) and duration (30 days to 1 year). Patients with shingles (n = 382) or PHN (n = 137) [defined as having symptoms for > or =90 days] from two large healthcare systems completed telephone interviews with similar questions to the Internet-based survey and also answered questions about their current experience with herpes zoster. We constructed generalized linear mixed models to evaluate the associations between demographic and clinical characteristics, the length and intensity of the health states and time trade-off and willingness-to-pay values. In time trade-off questions, community members offered a mean of 89 (95% CI 24, 182) discounted days to avoid the least severe scenario (pain level of 3 for 1 month) and a mean of 162 (95% CI 88, 259) discounted days to avoid the most severe scenario (pain level of 8 for 12 months). Compared with patients with shingles, community members traded more days to avoid low-severity scenarios but similar numbers of days

Representation of Solar Capacity Value in the ReEDS Capacity Expansion Model

Energy Technology Data Exchange (ETDEWEB)

Sigrin, B. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sullivan, P. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ibanez, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Margolis, R. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2014-03-01

An important issue for electricity system operators is the estimation of renewables' capacity contributions to reliably meeting system demand, or their capacity value. While the capacity value of thermal generation can be estimated easily, assessment of wind and solar requires a more nuanced approach due to the resource variability. Reliability-based methods, particularly assessment of the Effective Load-Carrying Capacity, are considered to be the most robust and widely-accepted techniques for addressing this resource variability. This report compares estimates of solar PV capacity value by the Regional Energy Deployment System (ReEDS) capacity expansion model against two sources. The first comparison is against values published by utilities or other entities for known electrical systems at existing solar penetration levels. The second comparison is against a time-series ELCC simulation tool for high renewable penetration scenarios in the Western Interconnection. Results from the ReEDS model are found to compare well with both comparisons, despite being resolved at a super-hourly temporal resolution. Two results are relevant for other capacity-based models that use a super-hourly resolution to model solar capacity value. First, solar capacity value should not be parameterized as a static value, but must decay with increasing penetration. This is because -- for an afternoon-peaking system -- as solar penetration increases, the system's peak net load shifts to later in the day -- when solar output is lower. Second, long-term planning models should determine system adequacy requirements in each time period in order to approximate LOLP calculations. Within the ReEDS model we resolve these issues by using a capacity value estimate that varies by time-slice. Within each time period the net load and shadow price on ReEDS's planning reserve constraint signals the relative importance of additional firm capacity.

Time-varying Concurrent Risk of Extreme Droughts and Heatwaves in California

Science.gov (United States)

Sarhadi, A.; Diffenbaugh, N. S.; Ausin, M. C.

2016-12-01

Anthropogenic global warming has changed the nature and the risk of extreme climate phenomena such as droughts and heatwaves. The concurrent of these nature-changing climatic extremes may result in intensifying undesirable consequences in terms of human health and destructive effects in water resources. The present study assesses the risk of concurrent extreme droughts and heatwaves under dynamic nonstationary conditions arising from climate change in California. For doing so, a generalized fully Bayesian time-varying multivariate risk framework is proposed evolving through time under dynamic human-induced environment. In this methodology, an extreme, Bayesian, dynamic copula (Gumbel) is developed to model the time-varying dependence structure between the two different climate extremes. The time-varying extreme marginals are previously modeled using a Generalized Extreme Value (GEV) distribution. Bayesian Markov Chain Monte Carlo (MCMC) inference is integrated to estimate parameters of the nonstationary marginals and copula using a Gibbs sampling method. Modelled marginals and copula are then used to develop a fully Bayesian, time-varying joint return period concept for the estimation of concurrent risk. Here we argue that climate change has increased the chance of concurrent droughts and heatwaves over decades in California. It is also demonstrated that a time-varying multivariate perspective should be incorporated to assess realistic concurrent risk of the extremes for water resources planning and management in a changing climate in this area. The proposed generalized methodology can be applied for other stochastic nature-changing compound climate extremes that are under the influence of climate change.

Effects of exercise on the formation of life-wide and value orientations of university students.

Directory of Open Access Journals (Sweden)

Marchenko O.U.

2011-03-01

Full Text Available In this paper we consider the common interests of the students responsible for their hobbies in their spare time and the formation of values of individual physical education students as a basis for self-motivation. In the experiment participated 70 students. Classes are held during the school year in the amount of 4 hours per week. Determined the level of impact studies on the structure and hierarchy of values of students.

Health significance and statistical uncertainty. The value of P-value.

Science.gov (United States)

Consonni, Dario; Bertazzi, Pier Alberto

2017-10-27

The P-value is widely used as a summary statistics of scientific results. Unfortunately, there is a widespread tendency to dichotomize its value in "P0.05" ("statistically not significant"), with the former implying a "positive" result and the latter a "negative" one. To show the unsuitability of such an approach when evaluating the effects of environmental and occupational risk factors. We provide examples of distorted use of P-value and of the negative consequences for science and public health of such a black-and-white vision. The rigid interpretation of P-value as a dichotomy favors the confusion between health relevance and statistical significance, discourages thoughtful thinking, and distorts attention from what really matters, the health significance. A much better way to express and communicate scientific results involves reporting effect estimates (e.g., risks, risks ratios or risk differences) and their confidence intervals (CI), which summarize and convey both health significance and statistical uncertainty. Unfortunately, many researchers do not usually consider the whole interval of CI but only examine if it includes the null-value, therefore degrading this procedure to the same P-value dichotomy (statistical significance or not). In reporting statistical results of scientific research present effects estimates with their confidence intervals and do not qualify the P-value as "significant" or "not significant".

Widely Linear Blind Adaptive Equalization for Transmitter IQ-Imbalance/Skew Compensation in Multicarrier Systems

DEFF Research Database (Denmark)

Porto da Silva, Edson; Zibar, Darko

2016-01-01

Simple analytical widely linear complex-valued models for IQ-imbalance and IQ-skew effects in multicarrier transmitters are presented. To compensate for such effects, a 4×4 MIMO widely linear adaptive equalizer is proposed and experimentally validated....

Predicting molybdenum toxicity to higher plants: Estimation of toxicity threshold values

Energy Technology Data Exchange (ETDEWEB)

McGrath, S.P., E-mail: steve.mcgrath@bbsrc.ac.u [Soil Science Department, Centre for Soils and Ecosystems Function, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Mico, C.; Zhao, F.J.; Stroud, J.L. [Soil Science Department, Centre for Soils and Ecosystems Function, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ (United Kingdom); Zhang, H.; Fozard, S. [Division of Environmental Science, Lancaster University, Lancaster LA1 4YQ (United Kingdom)

2010-10-15

Four plant species (oilseed rape, Brassica napus L.; red clover, Trifolium pratense L.; ryegrass, Lolium perenne L.; and tomato, Lycopersicon esculentum L.) were tested on ten soils varying widely in soil properties to assess molybdenum (Mo) toxicity. A larger range (66-fold-609-fold) of added Mo concentrations resulting in 50% inhibition of yield (ED{sub 50}) was found among soils than among plant species (2-fold-38-fold), which illustrated that the soils differed widely in the expression of Mo toxicity. Toxicity thresholds based on soil solution Mo narrowed the variation among soils compared to thresholds based on added Mo concentrations. We conclude that plant bioavailability of Mo in soil depends on Mo solubility, but this alone did not decrease the variability in observed toxicity enough to be used in risk assessment and that other soil properties influencing Mo toxicity to plants need to be considered. - Mo toxicity thresholds varied widely in different soils and therefore soil properties need to be taken into account in order to assess the risk of Mo exposure.

Robust topology optimization accounting for spatially varying manufacturing errors

DEFF Research Database (Denmark)

Schevenels, M.; Lazarov, Boyan Stefanov; Sigmund, Ole

2011-01-01

This paper presents a robust approach for the design of macro-, micro-, or nano-structures by means of topology optimization, accounting for spatially varying manufacturing errors. The focus is on structures produced by milling or etching; in this case over- or under-etching may cause parts...... optimization problem is formulated in a probabilistic way: the objective function is defined as a weighted sum of the mean value and the standard deviation of the structural performance. The optimization problem is solved by means of a Monte Carlo method: in each iteration of the optimization scheme, a Monte...

Valuing Individuals' Preferences and Health Choices of Physical Exercise.

Science.gov (United States)

Aboagye, Emmanuel

2017-06-01

The efficacy of physical exercise for the prevention and treatment of non-specific low back pain (LBP) is well documented, but little is known about how individuals value specific components of physical exercise, such as the type and design or the intensity and frequency of exercise. Other factors that influence individual differences in health choices and adherence are associated with individuals' attitudes toward and likelihood of performing recommended exercise regimens. Current evidence shows that efficacy is similar among exercise interventions, but their features vary widely. Thus it may be difficult for clinicians to discriminate between available options in clinical practice. Considering the many challenges in determining the form of exercise best suited to the individual patient, this commentary discusses some of the practical methods that could be used to elicit individual preference for recommended health care interventions. Such methods have the advantage of providing more information for health care decision making, particularly with regard to exercise interventions for LBP. This commentary also advocates for the use of patient preference in health care decisions.

Domestic estimated breeding values and genomic enhanced breeding values of bulls in comparison with their foreign genomic enhanced breeding values.

Science.gov (United States)

Přibyl, J; Bauer, J; Čermák, V; Pešek, P; Přibylová, J; Šplíchal, J; Vostrá-Vydrová, H; Vostrý, L; Zavadilová, L

2015-10-01

Estimated breeding values (EBVs) and genomic enhanced breeding values (GEBVs) for milk production of young genotyped Holstein bulls were predicted using a conventional BLUP - Animal Model, a method fitting regression coefficients for loci (RRBLUP), a method utilizing the realized genomic relationship matrix (GBLUP), by a single-step procedure (ssGBLUP) and by a one-step blending procedure. Information sources for prediction were the nation-wide database of domestic Czech production records in the first lactation combined with deregressed proofs (DRP) from Interbull files (August 2013) and domestic test-day (TD) records for the first three lactations. Data from 2627 genotyped bulls were used, of which 2189 were already proven under domestic conditions. Analyses were run that used Interbull values for genotyped bulls only or that used Interbull values for all available sires. Resultant predictions were compared with GEBV of 96 young foreign bulls evaluated abroad and whose proofs were from Interbull method GMACE (August 2013) on the Czech scale. Correlations of predictions with GMACE values of foreign bulls ranged from 0.33 to 0.75. Combining domestic data with Interbull EBVs improved prediction of both EBV and GEBV. Predictions by Animal Model (traditional EBV) using only domestic first lactation records and GMACE values were correlated by only 0.33. Combining the nation-wide domestic database with all available DRP for genotyped and un-genotyped sires from Interbull resulted in an EBV correlation of 0.60, compared with 0.47 when only Interbull data were used. In all cases, GEBVs had higher correlations than traditional EBVs, and the highest correlations were for predictions from the ssGBLUP procedure using combined data (0.75), or with all available DRP from Interbull records only (one-step blending approach, 0.69). The ssGBLUP predictions using the first three domestic lactation records in the TD model were correlated with GMACE predictions by 0.69, 0.64 and 0

Gray bootstrap method for estimating frequency-varying random vibration signals with small samples

Directory of Open Access Journals (Sweden)

Wang Yanqing

2014-04-01

Full Text Available During environment testing, the estimation of random vibration signals (RVS is an important technique for the airborne platform safety and reliability. However, the available methods including extreme value envelope method (EVEM, statistical tolerances method (STM and improved statistical tolerance method (ISTM require large samples and typical probability distribution. Moreover, the frequency-varying characteristic of RVS is usually not taken into account. Gray bootstrap method (GBM is proposed to solve the problem of estimating frequency-varying RVS with small samples. Firstly, the estimated indexes are obtained including the estimated interval, the estimated uncertainty, the estimated value, the estimated error and estimated reliability. In addition, GBM is applied to estimating the single flight testing of certain aircraft. At last, in order to evaluate the estimated performance, GBM is compared with bootstrap method (BM and gray method (GM in testing analysis. The result shows that GBM has superiority for estimating dynamic signals with small samples and estimated reliability is proved to be 100% at the given confidence level.

ARCHITECTURAL CONCEPTS FOR VALUE CHAINS

OpenAIRE

A.C. Janse van Rensburg

2012-01-01

ENGLISH ABSTRACT:The Porter Value Chain has been widely adopted by the business community as a mechanism to understand and comprehend complexity in business environments, with the ultimate goal of structuring the business to maximize its competitive advantage. Implementing the Value Chain is not easy: a number of organizations can testify to their failure to derive any benefits at all from this concept. To overcome this problem, an approach is presented to assist the organization in ...

Holographic cinematography of time-varying reflecting and time-varying phase objects using a Nd:YAG laser

Science.gov (United States)

Decker, A. J.

1982-01-01

The use of a Nd:YAG laser to record holographic motion pictures of time-varying reflecting objects and time-varying phase objects is discussed. Sample frames from both types of holographic motion pictures are presented. The holographic system discussed is intended for three-dimensional flow visualization of the time-varying flows that occur in jet-engine components.

Toward an integrated understanding of perceived biodiversity values and environmental conditions in a national park

Science.gov (United States)

van Riper, Carena J.; Kyle, Gerard T.; Sherrouse, Ben C.; Bagstad, Kenneth J.; Sutton, Stephen G.

2016-01-01

In spatial planning and management of protected areas, increased priority is being given to research that integrates social and ecological data. However, public viewpoints of the benefits provided by ecosystems are not easily quantified and often implicitly folded into natural resource management decisions. Drawing on a spatially explicit participatory mapping exercise and a Social Values for Ecosystem Services (SolVES) analysis tool, the present study empirically examined and integrated social values for ecosystem services and environmental conditions within Channel Islands National Park, California. Specifically, a social value indicator of perceived biodiversity was examined using on-site survey data collected from a sample of people who visited the park. This information was modeled alongside eight environmental conditions including faunal species richness for six taxa, vegetation density, categories of marine and terrestrial land cover, and distance to features relevant for decision-makers. Results showed that biodiversity value points assigned to places by the pooled sample of respondents were widely and unevenly mapped, which reflected the belief that biodiversity was embodied to varying degrees by multiple locations in the park. Models generated for two survey subgroups defined by their self-reported knowledge of the Channels Islands revealed distinct spatial patterns of these perceived values. Specifically, respondents with high knowledge valued large spaces that were publicly inaccessible and unlikely to contain on-ground biodiversity, whereas respondents with low knowledge valued places that were experienced first-hand. Accessibility and infrastructure were also important considerations for anticipating how and where people valued the protected land and seascapes of Channel Islands National Park.

Cultural values: can they explain self-reported health?

NARCIS (Netherlands)

Roudijk, B.; Donders, R.; Stalmeier, P.F.

2017-01-01

PURPOSE: Self-reported health (SRH) is a measure widely used in health research and population studies. Differences in SRH have been observed between countries and cultural values have been hypothesized to partly explain such differences. Cultural values can be operationalized by two cultural

The value of travel time variance

OpenAIRE

Fosgerau, Mogens; Engelson, Leonid

2010-01-01

This paper considers the value of travel time variability under scheduling preferences that are de�fined in terms of linearly time-varying utility rates associated with being at the origin and at the destination. The main result is a simple expression for the value of travel time variability that does not depend on the shape of the travel time distribution. The related measure of travel time variability is the variance of travel time. These conclusions apply equally to travellers who can free...

Genome-wide single-generation signatures of local selection in the panmictic European eel

DEFF Research Database (Denmark)

Pujolar, J. M.; Jacobsen, M. W.; Als, Thomas Damm

2014-01-01

Next-generation sequencing and the collection of genome-wide data allow identifying adaptive variation and footprints of directional selection. Using a large SNP data set from 259 RAD-sequenced European eel individuals (glass eels) from eight locations between 34 and 64oN, we examined the patterns...... of genome-wide genetic diversity across locations. We tested for local selection by searching for increased population differentiation using FST-based outlier tests and by testing for significant associations between allele frequencies and environmental variables. The overall low genetic differentiation...... with single-generation signatures of spatially varying selection acting on glass eels. After screening 50 354 SNPs, a total of 754 potentially locally selected SNPs were identified. Candidate genes for local selection constituted a wide array of functions, including calcium signalling, neuroactive ligand...

CFD comparison with centrifugal compressor measurements on a wide operating range

Directory of Open Access Journals (Sweden)

Arnou D.

2013-04-01

Full Text Available Centrifugal compressors are widely used in industrial applications thanks to their high efficiency. They are able to provide a wide operating range before reaching the flow barrier or surge limits. Performances and range are described by compressor maps obtained experimentally. After a description of performance test rig, this article compares measured centrifugal compressor performances with computational fluid dynamics results. These computations are performed at steady conditions with R134a refrigerant as fluid. Navier-Stokes equations, coupled with k-ε turbulence model, are solved by the commercial software ANSYS-CFX by means of volume finite method. Input conditions are varied in order to calculate several speed lines. Theoretical isentropic efficiency and theoretical surge line are finally compared to experimental data.

Emotions in freely varying and mono-pitched vowels, acoustic and EGG analyses.

Science.gov (United States)

Waaramaa, Teija; Palo, Pertti; Kankare, Elina

2015-12-01

Vocal emotions are expressed either by speech or singing. The difference is that in singing the pitch is predetermined while in speech it may vary freely. It was of interest to study whether there were voice quality differences between freely varying and mono-pitched vowels expressed by professional actors. Given their profession, actors have to be able to express emotions both by speech and singing. Electroglottogram and acoustic analyses of emotional utterances embedded in expressions of freely varying vowels [a:], [i:], [u:] (96 samples) and mono-pitched protracted vowels (96 samples) were studied. Contact quotient (CQEGG) was calculated using 35%, 55%, and 80% threshold levels. Three different threshold levels were used in order to evaluate their effects on emotions. Genders were studied separately. The results suggested significant gender differences for CQEGG 80% threshold level. SPL, CQEGG, and F4 were used to convey emotions, but to a lesser degree, when F0 was predetermined. Moreover, females showed fewer significant variations than males. Both genders used more hypofunctional phonation type in mono-pitched utterances than in the expressions with freely varying pitch. The present material warrants further study of the interplay between CQEGG threshold levels and formant frequencies, and listening tests to investigate the perceptual value of the mono-pitched vowels in the communication of emotions.

On the hypothesis-free testing of metabolite ratios in genome-wide and metabolome-wide association studies

Directory of Open Access Journals (Sweden)

Petersen Ann-Kristin

2012-06-01

Full Text Available Abstract Background Genome-wide association studies (GWAS with metabolic traits and metabolome-wide association studies (MWAS with traits of biomedical relevance are powerful tools to identify the contribution of genetic, environmental and lifestyle factors to the etiology of complex diseases. Hypothesis-free testing of ratios between all possible metabolite pairs in GWAS and MWAS has proven to be an innovative approach in the discovery of new biologically meaningful associations. The p-gain statistic was introduced as an ad-hoc measure to determine whether a ratio between two metabolite concentrations carries more information than the two corresponding metabolite concentrations alone. So far, only a rule of thumb was applied to determine the significance of the p-gain. Results Here we explore the statistical properties of the p-gain through simulation of its density and by sampling of experimental data. We derive critical values of the p-gain for different levels of correlation between metabolite pairs and show that B/(2*α is a conservative critical value for the p-gain, where α is the level of significance and B the number of tested metabolite pairs. Conclusions We show that the p-gain is a well defined measure that can be used to identify statistically significant metabolite ratios in association studies and provide a conservative significance cut-off for the p-gain for use in future association studies with metabolic traits.

Effect of storage conditions on the calorific value of municipal solid waste.

Science.gov (United States)

Nzioka, Antony Mutua; Hwang, Hyeon-Uk; Kim, Myung-Gyun; Yan, Cao Zheng; Lee, Chang-Soo; Kim, Young-Ju

2017-08-01

Storage conditions are considered to be an important factor as far as waste material characteristics are concerned. This experimental investigation was conducted using municipal solid waste (MSW) with a high moisture content and varying composition of organic waste. The objective of this study was to understand the effect of storage conditions and temperature on the moisture content and calorific value of the waste. Samples were subjected to two different storage conditions and investigated at specified temperatures. The composition of sample materials investigated was varied for each storage condition and temperature respectively. Gross calorific value was determined experimentally while net calorific value was calculated using empirical formulas proposed by other researchers. Results showed minimal changes in moisture content as well as in gross and net calorific values when the samples were subjected to sealed storage conditions. Moisture content reduced due to the ventilation process and the rate of moisture removal increased with a rise in storage temperature. As expected, rate of moisture removal had a positive effect on gross and net calorific values. Net calorific values also increased at varying rates with a simultaneous decrease in moisture content. Experimental investigation showed the effectiveness of ventilation in improving the combustion characteristics of the waste.

Comprehensive evaluation of genome-wide 5-hydroxymethylcytosine profiling approaches in human DNA.

Science.gov (United States)

Skvortsova, Ksenia; Zotenko, Elena; Luu, Phuc-Loi; Gould, Cathryn M; Nair, Shalima S; Clark, Susan J; Stirzaker, Clare

2017-01-01

The discovery that 5-methylcytosine (5mC) can be oxidized to 5-hydroxymethylcytosine (5hmC) by the ten-eleven translocation (TET) proteins has prompted wide interest in the potential role of 5hmC in reshaping the mammalian DNA methylation landscape. The gold-standard bisulphite conversion technologies to study DNA methylation do not distinguish between 5mC and 5hmC. However, new approaches to mapping 5hmC genome-wide have advanced rapidly, although it is unclear how the different methods compare in accurately calling 5hmC. In this study, we provide a comparative analysis on brain DNA using three 5hmC genome-wide approaches, namely whole-genome bisulphite/oxidative bisulphite sequencing (WG Bis/OxBis-seq), Infinium HumanMethylation450 BeadChip arrays coupled with oxidative bisulphite (HM450K Bis/OxBis) and antibody-based immunoprecipitation and sequencing of hydroxymethylated DNA (hMeDIP-seq). We also perform loci-specific TET-assisted bisulphite sequencing (TAB-seq) for validation of candidate regions. We show that whole-genome single-base resolution approaches are advantaged in providing precise 5hmC values but require high sequencing depth to accurately measure 5hmC, as this modification is commonly in low abundance in mammalian cells. HM450K arrays coupled with oxidative bisulphite provide a cost-effective representation of 5hmC distribution, at CpG sites with 5hmC levels >~10%. However, 5hmC analysis is restricted to the genomic location of the probes, which is an important consideration as 5hmC modification is commonly enriched at enhancer elements. Finally, we show that the widely used hMeDIP-seq method provides an efficient genome-wide profile of 5hmC and shows high correlation with WG Bis/OxBis-seq 5hmC distribution in brain DNA. However, in cell line DNA with low levels of 5hmC, hMeDIP-seq-enriched regions are not detected by WG Bis/OxBis or HM450K, either suggesting misinterpretation of 5hmC calls by hMeDIP or lack of sensitivity of the latter methods. We

Value Frameworks in Oncology: Comparative Analysis and Implications to the Pharmaceutical Industry.

Science.gov (United States)

Slomiany, Mark; Madhavan, Priya; Kuehn, Michael; Richardson, Sasha

2017-07-01

As the cost of oncology care continues to rise, composite value models that variably capture the diverse concerns of patients, physicians, payers, policymakers, and the pharmaceutical industry have begun to take shape. To review the capabilities and limitations of 5 of the most notable value frameworks in oncology that have emerged in recent years and to compare their relative value and application among the intended stakeholders. We compared the methodology of the American Society of Clinical Oncology (ASCO) Value Framework (version 2.0), the National Comprehensive Cancer Network Evidence Blocks, Memorial Sloan Kettering Cancer Center DrugAbacus, the Institute for Clinical and Economic Review Value Assessment Framework, and the European Society for Medical Oncology Magnitude of Clinical Benefit Scale, using a side-by-side comparative approach in terms of the input, scoring methodology, and output of each framework. In addition, we gleaned stakeholder insights about these frameworks and their potential real-world applications through dialogues with physicians and payers, as well as through secondary research and an aggregate analysis of previously published survey results. The analysis identified several framework-specific themes in their respective focus on clinical trial elements, breadth of evidence, evidence weighting, scoring methodology, and value to stakeholders. Our dialogues with physicians and our aggregate analysis of previous surveys revealed a varying level of awareness of, and use of, each of the value frameworks in clinical practice. For example, although the ASCO Value Framework appears nascent in clinical practice, physicians believe that the frameworks will be more useful in practice in the future as they become more established and as their outputs are more widely accepted. Along with patients and payers, who bear the burden of treatment costs, physicians and policymakers have waded into the discussion of defining value in oncology care, as well

Tendon material properties vary and are interdependent among turkey hindlimb muscles.

Science.gov (United States)

Matson, Andrew; Konow, Nicolai; Miller, Samuel; Konow, Pernille P; Roberts, Thomas J

2012-10-15

The material properties of a tendon affect its ability to store and return elastic energy, resist damage, provide mechanical feedback and amplify or attenuate muscle power. While the structural properties of a tendon are known to respond to a variety of stimuli, the extent to which material properties vary among individual muscles remains unclear. We studied the tendons of six different muscles in the hindlimb of Eastern wild turkeys to determine whether there was variation in elastic modulus, ultimate tensile strength and resilience. A hydraulic testing machine was used to measure tendon force during quasi-static lengthening, and a stress-strain curve was constructed. There was substantial variation in tendon material properties among different muscles. Average elastic modulus differed significantly between some tendons, and values for the six different tendons varied nearly twofold, from 829±140 to 1479±106 MPa. Tendons were stretched to failure, and the stress at failure, or ultimate tensile stress, was taken as a lower-limit estimate of tendon strength. Breaking tests for four of the tendons revealed significant variation in ultimate tensile stress, ranging from 66.83±14.34 to 112.37±9.39 MPa. Resilience, or the fraction of energy returned in cyclic length changes was generally high, and one of the four tendons tested was significantly different in resilience from the other tendons (range: 90.65±0.83 to 94.02±0.71%). An analysis of correlation between material properties revealed a positive relationship between ultimate tensile strength and elastic modulus (r(2)=0.79). Specifically, stiffer tendons were stronger, and we suggest that this correlation results from a constrained value of breaking strain, which did not vary significantly among tendons. This finding suggests an interdependence of material properties that may have a structural basis and may explain some adaptive responses observed in studies of tendon plasticity.

Effects of varying laser trimming geometries on thin film\\ud resistors

OpenAIRE

Alafogianni, Maria; Birkett, Martin; Penlington, Roger

2017-01-01

Purpose - This paper studies the effects of varying laser trim patterns on several performance parameters of thin film resistors such as the temperature coefficient of resistance (TCR) and target resistance value.\\ud \\ud Design/methodology/approach - The benefits and limitations of basic trim patterns are taken into consideration and the plunge cut, double plunge cut and the curved L-cut were selected to be modelled and tested experimentally. A computer simulation of the laser trim patterns h...

Compression distance can discriminate animals by genetic profile, build relationship matrices and estimate breeding values.

Science.gov (United States)

Hudson, Nicholas J; Porto-Neto, Laercio; Kijas, James W; Reverter, Antonio

2015-10-13

Genetic relatedness is currently estimated by a combination of traditional pedigree-based approaches (i.e. numerator relationship matrices, NRM) and, given the recent availability of molecular information, using marker genotypes (via genomic relationship matrices, GRM). To date, GRM are computed by genome-wide pair-wise SNP (single nucleotide polymorphism) correlations. We describe a new estimate of genetic relatedness using the concept of normalised compression distance (NCD) that is borrowed from Information Theory. Analogous to GRM, the resultant compression relationship matrix (CRM) exploits numerical patterns in genome-wide allele order and proportion, which are known to vary systematically with relatedness. We explored properties of the CRM in two industry cattle datasets by analysing the genetic basis of yearling weight, a phenotype of moderate heritability. In both Brahman (Bos indicus) and Tropical Composite (Bos taurus by Bos indicus) populations, the clustering inferred by NCD was comparable to that based on SNP correlations using standard principal component analysis approaches. One of the versions of the CRM modestly increased the amount of explained genetic variance, slightly reduced the 'missing heritability' and tended to improve the prediction accuracy of breeding values in both populations when compared to both NRM and GRM. Finally, a sliding window-based application of the compression approach on these populations identified genomic regions influenced by introgression of taurine haplotypes. For these two bovine populations, CRM reduced the missing heritability and increased the amount of explained genetic variation for a moderately heritable complex trait. Given that NCD can sensitively discriminate closely related individuals, we foresee CRM having possible value for estimating breeding values in highly inbred populations.

System-wide versus component-specific trust using multiple aids.

Science.gov (United States)

Keller, David; Rice, Stephen

2010-01-01

Previous research in operator trust toward automated aids has focused primarily on single aids. The current study focuses on how operator trust is affected by the presence of multiple aids. Two competing theories of multiple-trust are presented. A component-specific trust theory predicts that operators will differentially place their trust in automated aids that vary in reliability. A system-wide trust theory predicts that operators will treat multiple imperfect aids as one "system" and merge their trust across aids despite differences in the aids' reliability. A simulated flight task was used to test these theories, whereby operators performed a pursuit tracking task while concurrently monitoring multiple system gauges that were augmented with perfect or imperfect automated aids. The data revealed that a system-wide trust theory best predicted the data; operators merged their trust across both aids, behaving toward a perfectly reliable aid in the same manner as they did towards unreliable aids.

How to assess the value of medicines?

Science.gov (United States)

Simoens, Steven

2010-01-01

This study aims to discuss approaches to assessing the value of medicines. Economic evaluation assesses value by means of the incremental cost-effectiveness ratio (ICER). Health is maximized by selecting medicines with increasing ICERs until the budget is exhausted. The budget size determines the value of the threshold ICER and vice versa. Alternatively, the threshold value can be inferred from pricing/reimbursement decisions, although such values vary between countries. Threshold values derived from the value-of-life literature depend on the technique used. The World Health Organization has proposed a threshold value tied to the national GDP. As decision makers may wish to consider multiple criteria, variable threshold values and weighted ICERs have been suggested. Other approaches (i.e., replacement approach, program budgeting and marginal analysis) have focused on improving resource allocation, rather than maximizing health subject to a budget constraint. Alternatively, the generalized optimization framework and multi-criteria decision analysis make it possible to consider other criteria in addition to value.

How to assess the value of medicines?

Directory of Open Access Journals (Sweden)

Steven Simoens

2010-09-01

Full Text Available This study aims to discuss approaches to assessing the value of medicines. Economic evaluation assesses value by means of the incremental cost-effectiveness ratio (ICER. Health is maximised by selecting medicines with increasing ICERs until the budget is exhausted. The budget size determines the value of the threshold ICER and vice versa. Alternatively, the threshold value can be inferred from pricing/reimbursement decisions, although such values vary between countries. Threshold values derived from the value-of-life literature depend on the technique used. The WHO has proposed a threshold value tied to the national GDP. As decision makers may wish to consider multiple criteria, variable threshold values and weighted ICERs have been suggested. Other approaches (i.e. replacement approach, program budgeting and marginal analysis have focused on improving resource allocation, rather than maximising health subject to a budget constraint. Alternatively, the generalised optimisation framework and multi-criteria decision analysis make it possible to consider other criteria in addition to value.

Attention! Can choices for low value food over high value food be trained?

Science.gov (United States)

Zoltak, Michael J; Veling, Harm; Chen, Zhang; Holland, Rob W

2018-05-01

People choose high value food items over low value food items, because food choices are guided by the comparison of values placed upon choice alternatives. This value comparison process is also influenced by the amount of attention people allocate to different items. Recent research shows that choices for food items can be increased by training attention toward these items, with a paradigm named cued-approach training (CAT). However, previous work till now has only examined the influence of CAT on choices between two equally valued items. It has remained unclear whether CAT can increase choices for low value items when people choose between a low and high value food item. To address this question in the current study participants were cued to make rapid responses in CAT to certain low and high value items. Next, they made binary choices between low and high value items, where we systematically varied whether the low and high value items were cued or uncued. In two experiments, we found that participants overall preferred high over low value food items for real consumption. More important, their choices for low value items increased when only the low value item had been cued in CAT compared to when both low and high value items had not been cued. Exploratory analyses revealed that this effect was more pronounced for participants with a relatively small value difference between low and high value items. The present research thus suggests that CAT may be used to boost the choice and consumption of low value items via enhanced attention toward these items, as long as the value difference is not too large. Implications for facilitating choices for healthy food are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

UNUSUALLY WIDE BINARIES: ARE THEY WIDE OR UNUSUAL?

International Nuclear Information System (INIS)

Kraus, Adam L.; Hillenbrand, Lynne A.

2009-01-01

We describe an astrometric and spectroscopic campaign to confirm the youth and association of a complete sample of candidate wide companions in Taurus and Upper Sco. Our survey found 15 new binary systems (three in Taurus and 12 in Upper Sco) with separations of 3''-30'' (500-5000 AU) among all of the known members with masses of 2.5-0.012 M sun . The total sample of 49 wide systems in these two regions conforms to only some expectations from field multiplicity surveys. Higher mass stars have a higher frequency of wide binary companions, and there is a marked paucity of wide binary systems near the substellar regime. However, the separation distribution appears to be log-flat, rather than declining as in the field, and the mass ratio distribution is more biased toward similar-mass companions than the initial mass function or the field G-dwarf distribution. The maximum separation also shows no evidence of a limit at ∼ sun . We attribute this result to the post-natal dynamical sculpting that occurs for most field systems; our binary systems will escape to the field intact, but most field stars are formed in denser clusters and undergo significant dynamical evolution. In summary, only wide binary systems with total masses ∼ sun appear to be 'unusually wide'.

Values that matter, barriers that interfere: the struggle of Canadian nurses to enact their values.

Science.gov (United States)

Beagan, Brenda; Ells, Carolyn

2009-03-01

Qualitative interviews were conducted with 20 nurses in a Canadian city to explore the moral experience of nurses in their working lives. The participants were asked what they valued in their profession and how well their work lives enabled them act on their values. Almost uniformly, they expressed commitment to the values of helping others, caring, making a difference, patient-centredness, advocacy, professional integrity, holistic care, and sharing knowledge for patient empowerment. They identified several challenges and frustrations experienced in attempting to enact these values. System-level challenges included professional hierarchies, organizational structures, issues in the health-care system, and power dynamics. Removing these barriers cannot be left to nurses alone. It requires complex, wide-ranging strategies: system change, power restructuring, and the creation of ethical climates and cultures that support values that are essential to good patient care.

A varying-α brane world cosmology

International Nuclear Information System (INIS)

Youm, Donam

2001-08-01

We study the brane world cosmology in the RS2 model where the electric charge varies with time in the manner described by the varying fine-structure constant theory of Bekenstein. We map such varying electric charge cosmology to the dual variable-speed-of-light cosmology by changing system of units. We comment on cosmological implications for such cosmological models. (author)

Moveout analysis of wide-azimuth data in the presence of lateral velocity variation

KAUST Repository

Takanashi, Mamoru

2012-05-01

Moveout analysis of wide-azimuth reflection data seldom takes into account lateral velocity variations on the scale of spreadlength. However, velocity lenses (such as channels and reefs) in the overburden can cause significant, laterally varying errors in the moveout parameters and distortions in data interpretation. Here, we present an analytic expression for the normal-moveout (NMO) ellipse in stratified media with lateral velocity variation. The contribution of lateral heterogeneity (LH) is controlled by the second derivatives of the interval vertical traveltime with respect to the horizontal coordinates, along with the depth and thickness of the LH layer. This equation provides a quick estimate of the influence of velocity lenses and can be used to substantially mitigate the lens-induced distortions in the effective and interval NMO ellipses. To account for velocity lenses in nonhyperbolic moveout inversion of wide-azimuth data, we propose a prestack correction algorithm that involves computation of the lens-induced traveltime distortion for each recorded trace. The overburden is assumed to be composed of horizontal layers (one of which contains the lens), but the target interval can be laterally heterogeneous with dipping or curved interfaces. Synthetic tests for horizontally layered models confirm that our algorithm accurately removes lens-related azimuthally varying traveltime shifts and errors in the moveout parameters. The developed methods should increase the robustness of seismic processing of wide-azimuth surveys, especially those acquired for fracture-characterization purposes. © 2012 Society of Exploration Geophysicists.

Moveout analysis of wide-azimuth data in the presence of lateral velocity variation

KAUST Repository

Takanashi, Mamoru; Tsvankin, Ilya

2012-01-01

Moveout analysis of wide-azimuth reflection data seldom takes into account lateral velocity variations on the scale of spreadlength. However, velocity lenses (such as channels and reefs) in the overburden can cause significant, laterally varying errors in the moveout parameters and distortions in data interpretation. Here, we present an analytic expression for the normal-moveout (NMO) ellipse in stratified media with lateral velocity variation. The contribution of lateral heterogeneity (LH) is controlled by the second derivatives of the interval vertical traveltime with respect to the horizontal coordinates, along with the depth and thickness of the LH layer. This equation provides a quick estimate of the influence of velocity lenses and can be used to substantially mitigate the lens-induced distortions in the effective and interval NMO ellipses. To account for velocity lenses in nonhyperbolic moveout inversion of wide-azimuth data, we propose a prestack correction algorithm that involves computation of the lens-induced traveltime distortion for each recorded trace. The overburden is assumed to be composed of horizontal layers (one of which contains the lens), but the target interval can be laterally heterogeneous with dipping or curved interfaces. Synthetic tests for horizontally layered models confirm that our algorithm accurately removes lens-related azimuthally varying traveltime shifts and errors in the moveout parameters. The developed methods should increase the robustness of seismic processing of wide-azimuth surveys, especially those acquired for fracture-characterization purposes. © 2012 Society of Exploration Geophysicists.

Toward the integration of European natural gas markets:A time-varying approach

International Nuclear Information System (INIS)

Renou-Maissant, Patricia

2012-01-01

Over the past fifteen years, European gas markets have radically changed. In order to build a single European gas market, a new regulatory framework has been established through three European Gas Directives. The purpose of this article is to investigate the impact of the reforms in the natural gas industry on consumer prices, with a specific focus on gas prices for industrial use. The strength of the relationship between the industrial gas prices of six western European countries is studied by testing the Law of One Price for the period 1991–2009. Estimations were carried out using both cointegration analysis and time-varying parameter models. Results highlight an emerging and on-going process of convergence between the industrial gas prices in western Europe since 2001 for the six EU member states. The strength and the level of convergence differ widely between countries. Strong integration of gas markets in continental Europe, except for the Belgian market, has been established. It appears that the convergence process between continental countries and the UK is not completed. Thus, the integration of European gas markets remains an open issue and the question of how far integration will proceed will still be widely discussed in the coming years. - Highlights: ► We investigate the integration of European natural gas markets. ► We use both cointegration analysis and time-varying parameter models. ► We show the failure of cointegration techniques to take account of evolving processes. ► An emerging and on-going process of convergence between the industrial gas prices is at work. ► Strong integration of gas markets in continental Europe has been established.

The transition to value-based care.

Science.gov (United States)

Ray, Jordan C; Kusumoto, Fred

2016-10-01

Delivery of medical care is evolving rapidly worldwide. Over the past several years in the USA, there has been a rapid shift in reimbursement from a simple fee-for-service model to more complex models that attempt to link payment to quality and value. Change in any large system can be difficult, but with medicine, the transition to a value-based system has been particularly hard to implement because both quality and cost are difficult to quantify. Professional societies and other medical groups are developing different programs in an attempt to define high value care. However, applying a national standard of value for any treatment is challenging, since value varies from person to person, and the individual benefit must remain the central tenet for delivering best patient-centered medical care. Regardless of the specific operational features of the rapidly changing healthcare environment, physicians must first and foremost always remain patient advocates.

On innovation patterns and value-tensions in public services

DEFF Research Database (Denmark)

Fuglsang, Lars; Rønning, Rolf

2015-01-01

to the possibility of intertwined innovation patterns. Focusing public sector services, this paper agues that intertwined innovation patterns emerge within public services as a response to value-tensions. Values can be defined as measures for beneficial behaviour that guide innovation. Value-tensions in public...... services include tensions between the political, economic, communal, aesthetic and intellectual values. The contribution of the paper to service innovation research is the emphasis on the concept of intertwined innovation patterns, such as the intertwinement of science driven and task driven innovation....... Further, the paper contributes by pinpointing how varied values guide innovation in public services....

Model Study of Wave Overtopping of Marine Structure for a Wide Range of Geometric Parameters

DEFF Research Database (Denmark)

Kofoed, Jens Peter

2000-01-01

The objective of the study described in this paper is to enable estimation of wave overtopping rates for slopes/ramps given by a wide range of geometric parameters when subjected to varying wave conditions. To achieve this a great number of model tests are carried out in a wave tank using irregul...... 2-D waves. On the basis of the first part of these tests an exponential overtopping expression for a linear slope, including the effect of limited draught and varying slope angle, is presented. The plans for further tests with other slope geometries are described....

Cultural values and population health : A quantitative analysis of variations in cultural values, health behaviours and health outcomes among 42 European countries

NARCIS (Netherlands)

J.P. Mackenbach (Johan)

2014-01-01

textabstractVariations in 'culture' are often invoked to explain cross-national variations in health, but formal analyses of this relation are scarce. We studied the relation between three sets of cultural values and a wide range of health behaviours and health outcomes in Europe. Cultural values

Computational issues of solving the 1D steady gradually varied flow equation

Directory of Open Access Journals (Sweden)

Artichowicz Wojciech

2014-09-01

Full Text Available In this paper a problem of multiple solutions of steady gradually varied flow equation in the form of the ordinary differential energy equation is discussed from the viewpoint of its numerical solution. Using the Lipschitz theorem dealing with the uniqueness of solution of an initial value problem for the ordinary differential equation it was shown that the steady gradually varied flow equation can have more than one solution. This fact implies that the nonlinear algebraic equation approximating the ordinary differential energy equation, which additionally coincides with the wellknown standard step method usually applied for computing of the flow profile, can have variable number of roots. Consequently, more than one alternative solution corresponding to the same initial condition can be provided. Using this property it is possible to compute the water flow profile passing through the critical stage.

Wide-band CMOS low-noise amplifier exploiting thermal noise canceling

NARCIS (Netherlands)

Bruccoleri, F.; Klumperink, Eric A.M.; Nauta, Bram

Known elementary wide-band amplifiers suffer from a fundamental tradeoff between noise figure (NF) and source impedance matching, which limits the NF to values typically above 3 dB. Global negative feedback can be used to break this tradeoff, however, at the price of potential instability. In

The economic value of coffee (Coffea arabica) genetic resources

NARCIS (Netherlands)

Hein, L.G.; Gatzweiler, F.

2006-01-01

Whereas the economic value of genetic diversity is widely recognized there are, to date, relatively few experiences with the actual valuation of genetic resources. This paper presents an analysis of the economic value of Coffea arabica genetic resources contained in Ethiopian highland forests. The

Generating Value from Open Government Data

DEFF Research Database (Denmark)

Jetzek, Thorhildur; Avital, Michel; Bjørn-Andersen, Niels

2013-01-01

A driving force for change in society is the trend towards Open Government Data (OGD). While the value generated by OGD has been widely discussed by public bodies and other stakeholders, little attention has been paid to this phenomenon in the academic literature. Hence, we developed a conceptual...... model portraying how data as a resource can be transformed to value. We show the causal relationships between four contextual, enabling factors, four types of value generation mechanisms and value. We use empirical data from 61 countries to test these relationships, using the PLS method. The results...... mostly support the hypothesized relationships. Our conclusion is that if openness is complemented with resource governance, capabilities in society and technical connectivity, use of OGD will stimulate the generation of economic and social value through four different archetypical mechanisms: Efficiency...

Value Creation and Enhancement: Back to the Future

OpenAIRE

Aswath Damodaran

1999-01-01

In recent years, firms have turned to their attention increasingly to ways in which they can increase their value. A number of competing measures, each with claims to being the "best" approach to value creation, have been developed and marketed by investment banking firms and consulting firms. In this paper, we begin with a generic discounted cash flow model, and consider the ways in which value can be created or destroyed in a firm. We then look at two of the most widely used value enhanceme...

A consumption value-gap analysis for sustainable consumption.

Science.gov (United States)

Biswas, Aindrila

2017-03-01

Recent studies on consumption behavior have depicted environmental apprehension resulting from across wide consumer segments. However, this has not been widely reflected upon the growth in the market shares for green or environment-friendly products mostly because gaps exist between consumers' expectations and perceptions for those products. Previous studies have highlighted the impact of perceived value on potential demand, consumer satisfaction and behavioral intentions. The necessity to understand the effects of gaps in expected and perceived values on consumers' behavioral intention and potential demand for green products cannot be undermined as it shapes the consumers' inclination to repeated purchase and consumption and thus foster potential market demand. Pertaining to this reason, the study aims to adopt a consumption value-gap model based on the theory of consumption values to assess their impact on sustainable consumption behavior and market demand of green products. Consumption value refers to the level of fulfillment of consumer needs by assessment of net utility derived after effective comparison between the benefits (financial or emotional) and the gives (money, time, or energy). The larger the gaps the higher will be the adversarial impact on behavioral intentions. A structural equation modeling was applied to assess data collected through questionnaire survey. The results indicate that functional value-gap and environmental value-gap has the most adversarial impact on sustainable consumption behavior and market demand for green products.

Gender implications of forest product value chains in the Congo basin

NARCIS (Netherlands)

Ingram, V.; Schure, J.M.; Tieguhong, J.C.; Ndoye, O.; Awono, A.; Iponga, D.M.

2014-01-01

Activities and roles in value chains of forest products in the Congo Basin are highly gendered, varying with the product's characteristics, the segment of the chain and customary regulations and norms. High-value products are primarily male-harvested when customary rules govern tenure and access,

Lichen Persistence and Recovery in Response to Varied Volcanic Disturbances

Science.gov (United States)

Nelson, P.; Wheeler, T. B.

2015-12-01

Volcanic eruptions produce many ecological disturbances that structure vegetation. While lichens are sensitive to disturbances, little is known about their responses to volcanic disturbances, except for colonization of lava. We examined lichen community responses through time to different disturbances produced by the May 1, 2008 eruption of Volcan Chaiten in south-central Chile. Pre-eruption vegetation near the volcano was old-growth Valdivian temperate rainforest dominated by closed-canopy Nothofagus sp... In 2012, we installed thirteen 1-acre plots across volcanic disturbance zones on which a time-constrained search was done for all macrolichen species, each of which was assigned an approximate log10 categorical abundance. We also installed a 0.2 m2 quadrat on two representative trees per plot for repeat photography of lichen cover. We remeasured at least one plot per disturbance zone in 2014 and re-photographed tree quadrats in 2013 and 2014. We then analyzed species composition and abundance differences among disturbance zones. In 2012, the blast (pyroclastic density flow), scorch (standing scorched forest at the edge of the blast) and deep tephra (>10 cm) zones had the lowest lichen species richness (5-13 species), followed by reference (unimpacted) and shallow (lichen species since 2012 while the light tephra and reference were essentially unchanged. Gravel rain, gravel rain + pumice and flooded forest plots all had about the same number of species in 2014 as 2012. Lichen colonization and growth in tree quadrats varied widely, from very little colonization in the blast to prolific colonization in the gravel rain + pumice zone. Lichen's varied responses to different volcanic disturbances were attributable to varying degrees of mortality and subsequent availability of substrate, quantity of light and removal of competitors. While sensitive to disturbance, lichens are apparently resilient to and can quickly recolonize after a variety of large, violent volcanic

The value of travel time variance

DEFF Research Database (Denmark)

Fosgerau, Mogens; Engelson, Leonid

2011-01-01

This paper considers the value of travel time variability under scheduling preferences that are defined in terms of linearly time varying utility rates associated with being at the origin and at the destination. The main result is a simple expression for the value of travel time variability...... that does not depend on the shape of the travel time distribution. The related measure of travel time variability is the variance of travel time. These conclusions apply equally to travellers who can freely choose departure time and to travellers who use a scheduled service with fixed headway. Depending...... on parameters, travellers may be risk averse or risk seeking and the value of travel time may increase or decrease in the mean travel time....

Hot Ductility Behavior of Boron Containing Microalloyed Steels with Varying Manganese Contents

Science.gov (United States)

Brune, Tobias; Senk, Dieter; Walpot, Raphael; Steenken, Bernhard

2015-02-01

The hot ductility is measured for six different steel grades with different microalloying elements and with varying manganese contents using the hot tensile test machine with melting/solidification unit at the Department of Ferrous Metallurgy RWTH Aachen University. To identify the influence of manganese on hot ductility, tests are performed with varying the manganese content from 0.7 to 18.2 wt pct, a high manganese steel. Additionally, the effect of different cooling and strain rates is analyzed by changing the particular rate for selected samples in the minima. To investigate and detect the cause of cracking during testing, the fracture surfaces in the ductility minima are considered with scanning electron microscope-energy dispersive X-ray spectroscopy. Thermodynamic modeling is conducted on basis of the commercial software ThermoCalc©. A sharp decrease of the hot ductility is recognizable at 1398 K (1125 °C), at only 0.7 wt pct manganese because of the low manganese to sulfur ratio. The grades with a Mn content up to 1.9 wt pct show a good ductility with minimal ductility loss. In comparison, the steel grade with 18.2 wt pct has a poor hot ductility. Because of the formation of complex precipitates, where several alloying elements are involved, the influence of boron on hot ductility is not fully clarified. By increasing the cooling rate, the reduction of area values are shifted to smaller values. For high test temperatures, these measured values are decreased for lower strain rates. Thereby, an early drop of the ductility is noticeable for the high temperatures around 1373 K (1100 °C).

OPATs: Omnibus P-value association tests.

Science.gov (United States)

Chen, Chia-Wei; Yang, Hsin-Chou

2017-07-10

Combining statistical significances (P-values) from a set of single-locus association tests in genome-wide association studies is a proof-of-principle method for identifying disease-associated genomic segments, functional genes and biological pathways. We review P-value combinations for genome-wide association studies and introduce an integrated analysis tool, Omnibus P-value Association Tests (OPATs), which provides popular analysis methods of P-value combinations. The software OPATs programmed in R and R graphical user interface features a user-friendly interface. In addition to analysis modules for data quality control and single-locus association tests, OPATs provides three types of set-based association test: window-, gene- and biopathway-based association tests. P-value combinations with or without threshold and rank truncation are provided. The significance of a set-based association test is evaluated by using resampling procedures. Performance of the set-based association tests in OPATs has been evaluated by simulation studies and real data analyses. These set-based association tests help boost the statistical power, alleviate the multiple-testing problem, reduce the impact of genetic heterogeneity, increase the replication efficiency of association tests and facilitate the interpretation of association signals by streamlining the testing procedures and integrating the genetic effects of multiple variants in genomic regions of biological relevance. In summary, P-value combinations facilitate the identification of marker sets associated with disease susceptibility and uncover missing heritability in association studies, thereby establishing a foundation for the genetic dissection of complex diseases and traits. OPATs provides an easy-to-use and statistically powerful analysis tool for P-value combinations. OPATs, examples, and user guide can be downloaded from http://www.stat.sinica.edu.tw/hsinchou/genetics/association/OPATs.htm. © The Author 2017

A varying coefficient model to measure the effectiveness of mass media anti-smoking campaigns in generating calls to a Quitline.

Science.gov (United States)

Bui, Quang M; Huggins, Richard M; Hwang, Wen-Han; White, Victoria; Erbas, Bircan

2010-01-01

Anti-smoking advertisements are an effective population-based smoking reduction strategy. The Quitline telephone service provides a first point of contact for adults considering quitting. Because of data complexity, the relationship between anti-smoking advertising placement, intensity, and time trends in total call volume is poorly understood. In this study we use a recently developed semi-varying coefficient model to elucidate this relationship. Semi-varying coefficient models comprise parametric and nonparametric components. The model is fitted to the daily number of calls to Quitline in Victoria, Australia to estimate a nonparametric long-term trend and parametric terms for day-of-the-week effects and to clarify the relationship with target audience rating points (TARPs) for the Quit and nicotine replacement advertising campaigns. The number of calls to Quitline increased with the TARP value of both the Quit and other smoking cessation advertisement; the TARP values associated with the Quit program were almost twice as effective. The varying coefficient term was statistically significant for peak periods with little or no advertising. Semi-varying coefficient models are useful for modeling public health data when there is little or no information on other factors related to the at-risk population. These models are well suited to modeling call volume to Quitline, because the varying coefficient allowed the underlying time trend to depend on fixed covariates that also vary with time, thereby explaining more of the variation in the call model.

Value pluralism and incommensurability in Ecological Economics

DEFF Research Database (Denmark)

Pirgmaier, Elke; Urhammer, Emil

2015-01-01

problems of our time lie in a democracy where multiple values can be communicated. In order to provide inspiration for thinking about such a democracy, this paper provides an overview of a wide range of philosophical positions on values and value pluralism and analyses how values and value pluralism...... territory. This is reflected in a value hegemony framing everything from biodiversity to carbon emissions in monetary terms. We consider this a democratic problem since the diversity of values is thus not fairly represented in our current mode of decision-making. We believe that the solutions to the grand...... are treated in a selection of articles in ecological economics. The paper concludes that the treatment of values and incommensurability in ecological economics can be characterised as ambiguous. There is a need for further research on the theoretical aspects of these issues....

The application of value analysis techniques for complex problems

International Nuclear Information System (INIS)

Chiquelin, W.R.; Cossel, S.C.; De Jong, V.J.; Halverson, T.W.

1986-01-01

This paper discusses the application of the Value Analysis technique to the transuranic package transporter (TRUPACT). A team representing five different companies or organizations with diverse technical backgrounds was formed to analyze and recommend improvements. The results were a 38% systems-wide savings, if incorporated, and a shipping container which is volumetrically and payload efficient as well as user friendly. The Value Analysis technique is a proven tool widely used in many diverse areas both in the government and the private sector. Value Analysis uses functional diagramming of a piece of equipment or process to discretely identify every facet of the item being analyzed. A standard set of questions is then asked: What is it?, What does it do?, What does it cost?, What else will do the task?, and What would that cost? Using logic and a disciplined approach, the result of the Value Analysis performs the necessary functions at a high quality and the lowest overall cost

Zhang neural network for online solution of time-varying convex quadratic program subject to time-varying linear-equality constraints

International Nuclear Information System (INIS)

Zhang Yunong; Li Zhan

2009-01-01

In this Letter, by following Zhang et al.'s method, a recurrent neural network (termed as Zhang neural network, ZNN) is developed and analyzed for solving online the time-varying convex quadratic-programming problem subject to time-varying linear-equality constraints. Different from conventional gradient-based neural networks (GNN), such a ZNN model makes full use of the time-derivative information of time-varying coefficient. The resultant ZNN model is theoretically proved to have global exponential convergence to the time-varying theoretical optimal solution of the investigated time-varying convex quadratic program. Computer-simulation results further substantiate the effectiveness, efficiency and novelty of such ZNN model and method.

Influence of Different Cut-Off Values on the Diagnosis of Mild Cognitive Impairment in Parkinson's Disease

Directory of Open Access Journals (Sweden)

Inga Liepelt-Scarfone

2011-01-01

Full Text Available Comparable to Alzheimer's disease, mild cognitive impairment in Parkinson's disease (PD-MCI is associated with an increased risk for dementia. However different definitions of PD-MCI may have varying predictive accuracy for dementia. In a cohort of 101 nondemented Parkinson patients who underwent neuropsychological testing, the frequency of PD-MCI subjects and PD-MCI subtypes (i.e., amnestic/nonamnestic was determined by use of varying healthy population-based cut-off values. We also investigated the association between defined PD-MCI groups and ADL scales. Varying cut-off values for the definition of PD-MCI were found to affect frequency of PD-MCI subjects (9.9%–92.1% and, maybe more important, lead to a “shift” of proportion of detected PD-MCI subtypes especially within the amnestic single-domain subtype. Models using a strict cut-off value were significantly associated with lower ADL scores. Thus, the use of defined cut-off values for the definition of PD-MCI is highly relevant for comparison purposes. Strict cut-off values may have a higher predictive value for dementia.

Calibrations between chlorophyll meter values and chlorophyll contents vary as the result of differences in leaf structure

Science.gov (United States)

In order to relate leaf chlorophyll meter values with total leaf chlorophyll contents (µg cm-2), calibration equations are established with measured data on leaves. Many studies have documented differences in calibration equations using different species and using different growing conditions for th...

Development and Integration of Professional Core Values Among Practicing Clinicians.

Science.gov (United States)

McGinnis, Patricia Quinn; Guenther, Lee Ann; Wainwright, Susan F

2016-09-01

The physical therapy profession has adopted professional core values, which define expected values for its members, and developed a self-assessment tool with sample behaviors for each of the 7 core values. However, evidence related to the integration of these core values into practice is limited. The aims of this study were: (1) to gain insight into physical therapists' development of professional core values and (2) to gain insight into participants' integration of professional core values into clinical practice. A qualitative design permitted in-depth exploration of the development and integration of the American Physical Therapy Association's professional core values into physical therapist practice. Twenty practicing physical therapists were purposefully selected to explore the role of varied professional, postprofessional, and continuing education experiences related to exposure to professional values. The Core Values Self-Assessment and résumé sort served as prompts for reflection via semistructured interviews. Three themes were identified: (1) personal values were the foundation for developing professional values, which were further shaped by academic and clinical experiences, (2) core values were integrated into practice independent of practice setting and varied career paths, and (3) participants described the following professional core values as well integrated into their practice: integrity, compassion/caring, and accountability. Social responsibility was an area consistently identified as not being integrated into their practice. The Core Values Self-Assessment tool is a consensus-based document developed through a Delphi process. Future studies to establish reliability and construct validity of the tool may be warranted. Gaining an in-depth understanding of how practicing clinicians incorporate professional core values into clinical practice may shed light on the relationship between core values mastery and its impact on patient care. Findings may

Stability of Nonlinear Systems with Unknown Time-varying Feedback Delay

Science.gov (United States)

Chunodkar, Apurva A.; Akella, Maruthi R.

2013-12-01

This paper considers the problem of stabilizing a class of nonlinear systems with unknown bounded delayed feedback wherein the time-varying delay is 1) piecewise constant 2) continuous with a bounded rate. We also consider application of these results to the stabilization of rigid-body attitude dynamics. In the first case, the time-delay in feedback is modeled specifically as a switch among an arbitrarily large set of unknown constant values with a known strict upper bound. The feedback is a linear function of the delayed states. In the case of linear systems with switched delay feedback, a new sufficiency condition for average dwell time result is presented using a complete type Lyapunov-Krasovskii (L-K) functional approach. Further, the corresponding switched system with nonlinear perturbations is proven to be exponentially stable inside a well characterized region of attraction for an appropriately chosen average dwell time. In the second case, the concept of the complete type L-K functional is extended to a class of nonlinear time-delay systems with unknown time-varying time-delay. This extension ensures stability robustness to time-delay in the control design for all values of time-delay less than the known upper bound. Model-transformation is used in order to partition the nonlinear system into a nominal linear part that is exponentially stable with a bounded perturbation. We obtain sufficient conditions which ensure exponential stability inside a region of attraction estimate. A constructive method to evaluate the sufficient conditions is presented together with comparison with the corresponding constant and piecewise constant delay. Numerical simulations are performed to illustrate the theoretical results of this paper.

Effects of Long Cycles in Cash Flows on Present Value

OpenAIRE

Bell, Peter N

2015-01-01

This paper explores how present value varies over time when the underlying cash flow has a deterministic period. I assume that cash flows are known with certainty and follow a cycle with a long or short period. When the cash flow has a short period, the present value is relatively stable over time because the present value calculation smooths out several cycles. However, when the cash flow has a long period the present value itself develops a long and large cycle. These results are driven...

Value added medicines: what value repurposed medicines might bring to society?

Science.gov (United States)

Toumi, Mondher; Rémuzat, Cécile

2017-01-01

Background & objectives : Despite the wide interest surrounding drug repurposing, no common terminology has been yet agreed for these products and their full potential value is not always recognised and rewarded, creating a disincentive for further development. The objectives of the present study were to assess from a wide perspective which value drug repurposing might bring to society, but also to identify key obstacles for adoption of these medicines and to discuss policy recommendations. Methods : A preliminary comprehensive search was conducted to assess how the concept of drug repurposing was described in the literature. Following completion of the literature review, a primary research was conducted to get perspective of various stakeholders across EU member states on drug repurposing ( healthcare professionals, regulatory authorities and Health Technology Assessment (HTA) bodies/payers, patients, and representatives of the pharmaceutical industry developing medicines in this field). Ad hoc literature review was performed to illustrate, when appropriate, statements of the various stakeholders. Results : Various nomenclatures have been used to describe the concept of drug repurposing in the literature, with more or less broad definitions either based on outcomes, processes, or being a mix of both. In this context, Medicines for Europe (http://www.medicinesforeurope.com/value-added-medicines/) established one single terminology for these medicines, known as value added medicines, defined as 'medicines based on known molecules that address healthcare needs and deliver relevant improvements for patients, healthcare professionals and/or payers'. Stakeholder interviews highlighted three main potential benefits for value added medicines: (1) to address a number of medicine-related healthcare inefficiencies related to irrational use of medicines, non-availability of appropriate treatment options, shortage of mature products, geographical inequity in medicine access

Spacetime-varying couplings and Lorentz violation

International Nuclear Information System (INIS)

Kostelecky, V. Alan; Lehnert, Ralf; Perry, Malcolm J.

2003-01-01

Spacetime-varying coupling constants can be associated with violations of local Lorentz invariance and CPT symmetry. An analytical supergravity cosmology with a time-varying fine-structure constant provides an explicit example. Estimates are made for some experimental constraints

L-Asparagine crystals with wide gap semiconductor features: optical absorption measurements and density functional theory computations.

Science.gov (United States)

Zanatta, G; Gottfried, C; Silva, A M; Caetano, E W S; Sales, F A M; Freire, V N

2014-03-28

Results of optical absorption measurements are presented together with calculated structural, electronic, and optical properties for the anhydrous monoclinic L-asparagine crystal. Density functional theory (DFT) within the generalized gradient approximation (GGA) including dispersion effects (TS, Grimme) was employed to perform the calculations. The optical absorption measurements revealed that the anhydrous monoclinic L-asparagine crystal is a wide band gap material with 4.95 eV main gap energy. DFT-GGA+TS simulations, on the other hand, produced structural parameters in very good agreement with X-ray data. The lattice parameter differences Δa, Δb, Δc between theory and experiment were as small as 0.020, 0.051, and 0.022 Å, respectively. The calculated band gap energy is smaller than the experimental data by about 15%, with a 4.23 eV indirect band gap corresponding to Z → Γ and Z → β transitions. Three other indirect band gaps of 4.30 eV, 4.32 eV, and 4.36 eV are assigned to α3 → Γ, α1 → Γ, and α2 → Γ transitions, respectively. Δ-sol computations, on the other hand, predict a main band gap of 5.00 eV, just 50 meV above the experimental value. Electronic wavefunctions mainly originating from O 2p-carboxyl, C 2p-side chain, and C 2p-carboxyl orbitals contribute most significantly to the highest valence and lowest conduction energy bands, respectively. By varying the lattice parameters from their converged equilibrium values, we show that the unit cell is less stiff along the b direction than for the a and c directions. Effective mass calculations suggest that hole transport behavior is more anisotropic than electron transport, but the mass values allow for some charge mobility except along a direction perpendicular to the molecular layers of L-asparagine which form the crystal, so anhydrous monoclinic L-asparagine crystals could behave as wide gap semiconductors. Finally, the calculations point to a high degree of optical

L-asparagine crystals with wide gap semiconductor features: Optical absorption measurements and density functional theory computations

Energy Technology Data Exchange (ETDEWEB)

Zanatta, G.; Gottfried, C. [Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul, 90035-003 Porto Alegre-RS (Brazil); Silva, A. M. [Universidade Estadual do Piauí, 64260-000 Piripiri-Pi (Brazil); Caetano, E. W. S., E-mail: ewcaetano@gmail.com [Instituto de Educação, Ciência e Tecnologia do Ceará, 60040-531 Fortaleza-CE (Brazil); Sales, F. A. M.; Freire, V. N. [Departamento de Física, Universidade Federal do Ceará, Caixa Postal 6030, 60455-760 Fortaleza-CE (Brazil)

2014-03-28

Results of optical absorption measurements are presented together with calculated structural, electronic, and optical properties for the anhydrous monoclinic L-asparagine crystal. Density functional theory (DFT) within the generalized gradient approximation (GGA) including dispersion effects (TS, Grimme) was employed to perform the calculations. The optical absorption measurements revealed that the anhydrous monoclinic L-asparagine crystal is a wide band gap material with 4.95 eV main gap energy. DFT-GGA+TS simulations, on the other hand, produced structural parameters in very good agreement with X-ray data. The lattice parameter differences Δa, Δb, Δc between theory and experiment were as small as 0.020, 0.051, and 0.022 Å, respectively. The calculated band gap energy is smaller than the experimental data by about 15%, with a 4.23 eV indirect band gap corresponding to Z → Γ and Z → β transitions. Three other indirect band gaps of 4.30 eV, 4.32 eV, and 4.36 eV are assigned to α3 → Γ, α1 → Γ, and α2 → Γ transitions, respectively. Δ-sol computations, on the other hand, predict a main band gap of 5.00 eV, just 50 meV above the experimental value. Electronic wavefunctions mainly originating from O 2p–carboxyl, C 2p–side chain, and C 2p–carboxyl orbitals contribute most significantly to the highest valence and lowest conduction energy bands, respectively. By varying the lattice parameters from their converged equilibrium values, we show that the unit cell is less stiff along the b direction than for the a and c directions. Effective mass calculations suggest that hole transport behavior is more anisotropic than electron transport, but the mass values allow for some charge mobility except along a direction perpendicular to the molecular layers of L-asparagine which form the crystal, so anhydrous monoclinic L-asparagine crystals could behave as wide gap semiconductors. Finally, the calculations point to a high degree of optical

Applying the Expectancy-Value Model to understand health values.

Science.gov (United States)

Zhang, Xu-Hao; Xie, Feng; Wee, Hwee-Lin; Thumboo, Julian; Li, Shu-Chuen

2008-03-01

Expectancy-Value Model (EVM) is the most structured model in psychology to predict attitudes by measuring attitudinal attributes (AAs) and relevant external variables. Because health value could be categorized as attitude, we aimed to apply EVM to explore its usefulness in explaining variances in health values and investigate underlying factors. Focus group discussion was carried out to identify the most common and significant AAs toward 5 different health states (coded as 11111, 11121, 21221, 32323, and 33333 in EuroQol Five-Dimension (EQ-5D) descriptive system). AAs were measured in a sum of multiplications of subjective probability (expectancy) and perceived value of attributes with 7-point Likert scales. Health values were measured using visual analog scales (VAS, range 0-1). External variables (age, sex, ethnicity, education, housing, marital status, and concurrent chronic diseases) were also incorporated into survey questionnaire distributed by convenience sampling among eligible respondents. Univariate analyses were used to identify external variables causing significant differences in VAS. Multiple linear regression model (MLR) and hierarchical regression model were used to investigate the explanatory power of AAs and possible significant external variable(s) separately or in combination, for each individual health state and a mixed scenario of five states, respectively. Four AAs were identified, namely, "worsening your quality of life in terms of health" (WQoL), "adding a burden to your family" (BTF), "making you less independent" (MLI) and "unable to work or study" (UWS). Data were analyzed based on 232 respondents (mean [SD] age: 27.7 [15.07] years, 49.1% female). Health values varied significantly across 5 health states, ranging from 0.12 (33333) to 0.97 (11111). With no significant external variables identified, EVM explained up to 62% of the variances in health values across 5 health states. The explanatory power of 4 AAs were found to be between 13

Quantitation in planar renal scintigraphy: which μ value should be used?

International Nuclear Information System (INIS)

Hindie, E.; Jeanguillaume, C.; Galle, P.; Prigent, A.

1999-01-01

The attenuation coefficient value μ used by different authors for quantitation in planar renal scintigraphy varies greatly, from the theoretical value of 0.153 cm -1 (appropriate for scatter-free data) down to 0.099 cm -1 (empirical value assumed to compensate for both scatter and attenuation). For a 6-cm-deep kidney, such variations introduce up to 30% differences in absolute measurement of kidney activity. Using technetium-99m phantom studies, we determined the μ values that would yield accurate kidney activity quantitation for different energy windows corresponding to different amounts of scatter, and when using different image analysis approaches similar to those used in renal quantitation. With the 20% energy window, it was found that the μ value was strongly dependent on the size of the region of interest (ROI) and on whether background subtraction was performed: the μ value thus varied from 0.119 cm -1 (loose ROI, no background subtraction) to 0.150 cm -1 (kidney ROI and background subtraction). When using data from an energy window that could be considered scatter-free, the μ value became almost independent of the image analysis scheme. It is concluded that: (1) when performing background subtraction, which implicitly reduces the effect of scatter, the μ value to be used for accurate quantitation is close to the theoretical μ value; (2) if the acquired data were initially corrected for scatter, the appropriate μ value would then be the theoretical μ value, whatever the image analysis scheme. (orig.)

CODATA recommended values of the fundamental constants

International Nuclear Information System (INIS)

Mohr, Peter J.; Taylor, Barry N.

2000-01-01

A review is given of the latest Committee on Data for Science and Technology (CODATA) adjustment of the values of the fundamental constants. The new set of constants, referred to as the 1998 values, replaces the values recommended for international use by CODATA in 1986. The values of the constants, and particularly the Rydberg constant, are of relevance to the calculation of precise atomic spectra. The standard uncertainty (estimated standard deviation) of the new recommended value of the Rydberg constant, which is based on precision frequency metrology and a detailed analysis of the theory, is approximately 1/160 times the uncertainty of the 1986 value. The new set of recommended values as well as a searchable bibliographic database that gives citations to the relevant literature is available on the World Wide Web at physics.nist.gov/constants and physics.nist.gov/constantsbib, respectively

Nonlinear radiation transport problems involving widely varying mean free paths

International Nuclear Information System (INIS)

Chapline, G. Jr.; Wood, L.

1976-01-01

In this report a method is given for modifying the Monte-Carlo approach so that one can accurately treat problems that involve both large and small mean free paths. This method purports to offer the advantages of the general Monte Carlo technique as far as relatively great accuracy of simulation of microscopic physical phenomena is concerned, and the advantage of a diffusion theory approach as far as decent time steps in thick problems are concerned; it does suffer from something of the statistical fluctuation problems of the Monte Carlo, although in analytically attenuated and modified form

The contribution of technology to added value

CERN Document Server

Fernandes, António S C

2013-01-01

There is a wide consensus that introduction of technology to the production process contributes to an overall economic value, however, confusion between technology, knowledge and capital often makes value calculations ambiguous and non-objective. The Contribution of Technology to Added Value addresses not only this issue of definition but also provides a production model to assess the value contribution of technology within the production process. A clarification  of fundamental semantics  provides a significant taxonomy for technology dependence, and allows understanding and modeling of how knowledge, technology and capital individually contribute to production and to value adding. A new technology dependence taxonomy is proposed and assessed following chapters explaining growth models, the KTC model and technology index values. Balancing theoretical knowledge with real-world data and applications The Contribution of Technology to Added Value clarifies the issue of value adding for a range of different vie...

Delivering Value In A Global Aerospace Manufacturer Through The Effective Use Of Numerical Process Simulation

Science.gov (United States)

Ward, M. J.; Walløe, S. J.

2004-06-01

Numerical models are used extensively in the aerospace sector to identify appropriate manufacturing parameters, and to minimize the risk associated with new product introduction and manufacturing change. This usage is equally prevalent in original equipment manufacturers (OEMs), and in their supply chains. The wide range of manufacturing processes and production environments involved, coupled with the varying degrees of technology maturity associated with numerical models of different processes leads to a situation of significant complexity from the OEM perspective. In addition, the intended use of simulation technology can vary considerably between applications, from simple geometric assessment of die shape at one extreme, to full process design or development at the other. Consequently there is an increasing trend towards multi-scale modelling, i.e. the use of several different model types, with differing attributes in terms of accuracy and speed to support a range of different new product introduction decisions. This makes the allocation of appropriate levels of activity to the research and implementation of new capabilities a difficult problem. This paper uses a number of industrial cases studies to illustrate a framework for making such allocation decisions such that value to the OEM is maximized, and investigates how such a framework is likely to shift over the next few years based on technological developments.

Wilderness values: Perspectives from non-economic social science

Science.gov (United States)

Daniel R. Williams; Alan E. Watson

2007-01-01

The concept of “values” is one of the most widely used to characterize the human dimensions of natural resources. Yet, clearly it means many different things in different disciplines and in everyday discourse. Background information regarding values from a non-economic social science perspective is provided, with an aim towards stretching the dominant economic paradigm...

Leadership values in academic medicine.

Science.gov (United States)

Souba, Wiley W; Day, David V

2006-01-01

To gain a deeper understanding of the guiding core values that deans of academic medical centers (AMCs) considered most essential for their leadership and the major leadership challenges that confront them. In 2003-04, semistructured interviews of 18 deans at U.S. colleges of medicine or AMCs were organized around four dimensions: background, leadership challenges, organizational effectiveness, and systems enablers/restrainers for leadership. A values Q-sort was used to determine how widely core values were shared among deans and how the complex challenges they faced did or did not align with these values. Fourteen of the 18 (78%) deans identified financial difficulties as their most pressing leadership challenge, followed by weak institutional alignment (61%), staffing problems (33%), and poor morale (28%). Open, candid communication was reported as the most effective means of addressing these complex problems. Enacting espoused shared values and having a positive attitude were identified as the most important enablers of systemic leadership, whereas micromanagement and difficult people were the major restraints. Q-sort results on 38 positive leadership values indicated that participants considered integrity most essential. Integrity was positively correlated with humanistic values and negatively correlated with results. Vision, another highly espoused value, correlated strongly with performance-oriented values but correlated negatively with humanistic values. A dynamic tension exists in AMCs between humanistic values and performance-based core values. The ability to manage that tension (i.e., when to prioritize one set of values over the other) is inherent in a dean's work.

Cold fission description with constant and varying mass asymmetries

International Nuclear Information System (INIS)

Duarte, S.B.; Rodriguez, O.; Tavares, O.A.P.; Goncalves, M.; Garcia, F.; Guzman, F.

1998-01-01

Different description for varying the mass asymmetry in the fragmentation process are used to calculate the cold fission barrier penetrability. The relevance of the appropriate choice for both the description of the pre-scission phase and inertia coefficient to unify alpha decay, cluster radioactivity, and spontaneous cold fission processes in the same theoretical framework is explicitly shown. We calculate the half-life of all possible partition modes of nuclei of A > 200 following the most recent Mass Table by Audi and Wapstra. It is shown that if one uses the description in which the mass asymmetry is maintained constant during the fragmentation process, the experimental half-life-values and mass yield of 234 U cold fission are satisfactorily reproduced. (author)

Magnetization Switching of a Co /Pt Multilayered Perpendicular Nanomagnet Assisted by a Microwave Field with Time-Varying Frequency

Science.gov (United States)

Suto, Hirofumi; Kanao, Taro; Nagasawa, Tazumi; Mizushima, Koichi; Sato, Rie

2018-05-01

Microwave-assisted magnetization switching (MAS) is attracting attention as a method for reversing nanomagnets with a high magnetic anisotropy by using a small-amplitude magnetic field. We experimentally study MAS of a perpendicularly magnetized nanomagnet by applying a microwave magnetic field with a time-varying frequency. Because the microwave field frequency can follow the nonlinear decrease of the resonance frequency, larger magnetization excitation than that in a constant-frequency microwave field is induced, which enhances the MAS effect. The switching field decreases almost linearly as the start value of the time-varying microwave field frequency increases, and it becomes smaller than the minimum switching field in a constant-frequency microwave field. To obtain this enhancement of the MAS effect, the end value of the time-varying microwave field frequency needs to be almost the same as or lower than the critical frequency for MAS in a constant-frequency microwave field. In addition, the frequency change typically needs to take 1 ns or longer to make the rate of change slow enough for the magnetization to follow the frequency change. This switching behavior is qualitatively explained by the theory based on the macrospin model.

Application and development of non contact angle-wide viewing system in vitreous retinal surgery

Directory of Open Access Journals (Sweden)

Rong-Hua He

2016-07-01

Full Text Available Wide-angle viewing system as an important auxiliary device can clearly observe the whole fundus field of vision in vitreous surgery, which enable vitreoretinal surgery more efficient, safer and more effective. So it has very high application value in ophthalmologic operation. In this paper, we studied the development and application of wide-angle viewing system in vitreoretinal surgery in recent years, from which we summed up the advantage of non-contact wide-angle viewing system in clinical field, and pointed out the shortcomings. The ultimate goal is to make the non-contact wide-angle viewing system better applied in vitreous surgery.

Numerical modeling of rapidly varying flows using HEC-RAS and WSPG models.

Science.gov (United States)

Rao, Prasada; Hromadka, Theodore V

2016-01-01

The performance of two popular hydraulic models (HEC-RAS and WSPG) for modeling hydraulic jump in an open channel is investigated. The numerical solutions are compared with a new experimental data set obtained for varying channel bottom slopes and flow rates. Both the models satisfactorily predict the flow depths and location of the jump. The end results indicate that the numerical models output is sensitive to the value of chosen roughness coefficient. For this application, WSPG model is easier to implement with few input variables.

Political risk in fair market value estimates

International Nuclear Information System (INIS)

Gruy, H.J.; Hartsock, J.H.

1996-01-01

Political risk arises from unstable governments, commercial establishments and infrastructure as well as labor unrest. All these factors vary from country to country and from time to time. Banks and insurance companies quantify these risks, but they are reluctant to divulge their opinions for fear of alienating possible customers that have been assigned a high risk. An investment in a fixed property such as an oil and gas lease, concession or other mineral interest is subject to political risk. No one will deny that money to be received several years in the future has a greater value today in a country with a stable government, stable tax regime, a sound economy and reliable labor force than in a Third World country where a revolution is brewing. Even in stable countries, the risk of tax law changes, exorbitant environmental production regulations and cleanup costs may vary. How do these factors affect fair market value and how are these calculations made? An important consideration discussed in this paper is the treatment of capital investments

Estimating time-varying RSA to examine psychophysiological linkage of marital dyads.

Science.gov (United States)

Gates, Kathleen M; Gatzke-Kopp, Lisa M; Sandsten, Maria; Blandon, Alysia Y

2015-08-01

One of the primary tenets of polyvagal theory dictates that parasympathetic influence on heart rate, often estimated by respiratory sinus arrhythmia (RSA), shifts rapidly in response to changing environmental demands. The current standard analytic approach of aggregating RSA estimates across time to arrive at one value fails to capture this dynamic property within individuals. By utilizing recent methodological developments that enable precise RSA estimates at smaller time intervals, we demonstrate the utility of computing time-varying RSA for assessing psychophysiological linkage (or synchrony) in husband-wife dyads using time-locked data collected in a naturalistic setting. © 2015 Society for Psychophysiological Research.

Value driven classroom management-the congruence between the preferred and the democratic values

Directory of Open Access Journals (Sweden)

Fatma Özmen

2013-11-01

Full Text Available The rapid changes in all areas of communities have raised the level of concerns about weakening of the societal values. And many academics and researchers have begun to become interested in the issues for placing especially the democratic values in education more than ever before, in order to constitute more livable social environments. The goal of this study is, on the basis of gender variable, to determine what values have driven the teachers in their classroom management practices, and to find out if these values are congruent with the democratic principles. The research group comprises 68 teachers working in Regional Public Boarding Schools. The teachers were asked to list the most and the least preferred values in classroom management from a predetermined value list. The analysis of the data revealed that the most desired 10 values used by teachers in classroom management practices were generally common between female and male gender groups and both groups’ preferences indicated similar results. ‘Honesty’ and ‘responsibility’ take at the top of the most preferred value list. However, the value of ‘equality’ which is indispensible for maintaining democracyin classroom, was preferred by less than half of the teachers. And the values such as peace, freedom, social recognition and the like were not given place in the most preferred value list. The least preferred ten values were generally the ones which were not directly related to democracy. These results indicate that some essential values related to democracy are not given much importance. It is recommended that teachers should be trained well about creating democratic classroom settings especially in pre-service education. And, school leaders should give utmost importance to constitute a democratic school environment; and school wide practices should be congruent with democratic principles so as to form it as a life style.

Path coefficient analysis of zinc dynamics in varying soil environment

International Nuclear Information System (INIS)

Rattan, R.K.; Phung, C.V.; Singhal, S.K.; Deb, D.L.; Singh, A.K.

1994-01-01

Influence of soil properties on labile zinc, as measured by diethylene-triamine pentaacetic acid (DTPA) and zinc-65, and self-diffusion coefficients of zinc was assessed on 22 surface soil samples varying widely in their characteristics following linear regression and path coefficient analysis techniques. DTPA extractable zinc could be predicted from organic carbon status and pH of the soil with a highly significant coefficient of determination (R 2 =0.84 ** ). Ninety seven per cent variation in isotopically exchangeable zinc was explained by pH, clay content and cation exchange capacity (CEC) of soil. The self-diffusion coefficients (DaZn and DpZn) and buffer power of zinc exhibited exponential relationship with soil properties, pH being the most dominant one. Soil properties like organic matter, clay content etc. exhibited indirect effects on zinc diffusion rates via pH only. (author). 13 refs., 6 tabs

Reference Values for Maximal Inspiratory Pressure: A Systematic Review

Directory of Open Access Journals (Sweden)

Isabela MB Sclauser Pessoa

2014-01-01

Full Text Available BACKGROUND: Maximal inspiratory pressure (MIP is the most commonly used measure to evaluate inspiratory muscle strength. Normative values for MIP vary significantly among studies, which may reflect differences in participant demographics and technique of MIP measurement.

Controversy in the allometric application of fixed- versus varying-exponent models: a statistical and mathematical perspective.

Science.gov (United States)

Tang, Huadong; Hussain, Azher; Leal, Mauricio; Fluhler, Eric; Mayersohn, Michael

2011-02-01

This commentary is a reply to a recent article by Mahmood commenting on the authors' article on the use of fixed-exponent allometry in predicting human clearance. The commentary discusses eight issues that are related to criticisms made in Mahmood's article and examines the controversies (fixed-exponent vs. varying-exponent allometry) from the perspective of statistics and mathematics. The key conclusion is that any allometric method, which is to establish a power function based on a limited number of animal species and to extrapolate the resulting power function to human values (varying-exponent allometry), is infused with fundamental statistical errors. Copyright © 2010 Wiley-Liss, Inc.

Exploring the Value Orientations of Inuit and White Students: An Empirical Inquiry.

Science.gov (United States)

Roberts, Lance W.; And Others

1989-01-01

Finds that, among 46 Inuit and 11 White 10-16-year-old students in the Northwest Territories (Canada), Inuit students had less modern values than their white peers, but Inuit scores varied considerably both within and among the 5 value orientations examined. Contains 34 references. (SV)

Intelligibility and Clarity of Reverberant Speech: Effects of Wide Dynamic Range Compression Release Time and Working Memory

Science.gov (United States)

Reinhart, Paul N.; Souza, Pamela E.

2016-01-01

Purpose: The purpose of this study was to examine the effects of varying wide dynamic range compression (WDRC) release time on intelligibility and clarity of reverberant speech. The study also considered the role of individual working memory. Method: Thirty older listeners with mild to moderately-severe sloping sensorineural hearing loss…

Free Vibration Behavior of a Gradient Elastic Beam with Varying Cross Section

Directory of Open Access Journals (Sweden)

Mustafa Özgür Yayli

2014-01-01

Full Text Available Based on strain gradient elasticity theory, a finite element procedure is proposed for computation of natural frequencies for the microbeams of constant width and linear varying depth. Weak form formulation of the equation of motion is obtained first as in common classical finite element procedure in terms of various kinds of boundary conditions. Gradient elastic shape functions are used for interpolating deflection inside a finite element. Stiffness and mass matrices are then calculated to solve the microbeam eigen value problem. A solution for natural frequencies is obtained using characteristic equation of microbeam in gradient elasticity. The results are given in a series of figures and compared with their classical counterparts. The effect of various slope values on the natural frequencies are examined in some numerical examples. Comparison with the classical elasticity theory is also performed to verify the present study.

Exogenous Variables and Value-Added Assessments: A Fatal Flaw

Science.gov (United States)

Berliner, David C.

2014-01-01

Background: There has been rapid growth in value-added assessment of teachers to meet the widely supported policy goal of identifying the most effective and the most ineffective teachers in a school system. The former group is to be rewarded while the latter group is to be helped or fired for their poor performance. But, value-added approaches to…

Early Years Education and the Value for Money Folklore

Science.gov (United States)

Campbell-Barr, Verity

2012-01-01

This article is intended as a contribution to the debate on the role of human capital in determining value for money in early years education. The article explores how the idea that early years education offers value for money has become folklore amongst policymakers and more widely. However, drawing on both interview data and existing literature…

Probabilistic fuzzy systems in value-at-risk estimation

NARCIS (Netherlands)

Almeida, R.J.; Kaymak, U.

2009-01-01

Value-at-risk (VaR) is a popular measure for quantifying the market risk that a financial institution faces into a single number. Owing to the complexity of financial markets, the risks associated with a portfolio varies over time. Consequently, advanced methods of VaR estimation use parametric

Online Estimation of Time-Varying Volatility Using a Continuous-Discrete LMS Algorithm

Directory of Open Access Journals (Sweden)

Jacques Oksman

2008-09-01

Full Text Available The following paper addresses a problem of inference in financial engineering, namely, online time-varying volatility estimation. The proposed method is based on an adaptive predictor for the stock price, built from an implicit integration formula. An estimate for the current volatility value which minimizes the mean square prediction error is calculated recursively using an LMS algorithm. The method is then validated on several synthetic examples as well as on real data. Throughout the illustration, the proposed method is compared with both UKF and offline volatility estimation.

Fracture Analysis of the FAA/NASA Wide Stiffened Panels

Science.gov (United States)

Seshadri, B. R.; Newman, J. C., Jr.; Dawicke, D. S.; Young, R. D.

1999-01-01

This paper presents the fracture analyses conducted on the FAA/NASA stiffened and unstiffened panels using the STAGS (STructural Analysis of General Shells) code with the critical crack-tip-opening angle (CTOA) fracture criterion. The STAGS code with the "plane-strain" core option was used in all analyses. Previous analyses of wide, flat panels have shown that the high-constraint conditions around a crack front, like plane strain, has to be modeled in order for the critical CTOA fracture criterion to predict wide panel failures from small laboratory tests. In the present study, the critical CTOA value was determined from a wide (unstiffened) panel with anti-buckling guides. The plane-strain core size was estimated from previous fracture analyses and was equal to about the sheet thickness. Rivet flexibility and stiffener failure was based on methods and criteria, like that currently used in industry. STAGS and the CTOA criterion were used to predict load-against-crack extension for the wide panels with a single crack and multiple-site damage cracking at many adjacent rivet holes. Analyses were able to predict stable crack growth and residual strength within a few percent (5%) of stiffened panel tests results but over predicted the buckling failure load on an unstiffened panel with a single crack by 10%.

Natural background radiation exposures world-wide

International Nuclear Information System (INIS)

Bennett, B.G.

1993-01-01

The average radiation dose to the world's population from natural radiation sources has been assessed by UNSCEAR to be 2.4 mSv per year. The components of this exposure, methods of evaluation and, in particular, the variations in the natural background levels are presented in this paper. Exposures to cosmic radiation range from 0.26 mSv per year at sea level to 20 times more at an altitude of 6000 m. Exposures to cosmogenic radionuclides ( 3 H, 14 C) are relatively insignificant and little variable. The terrestrial radionuclides 40 K, 238 U, and 232 Th and the decay products of the latter two constitute the remainder of the natural radiation exposure. Wide variations in exposure occur for these components, particularly for radon and its decay products, which can accumulate to relatively high levels indoors. Unusually high exposures to uranium and thorium series radionuclides characterize the high natural background areas which occur in several localized regions in the world. Extreme values in natural radiation exposures have been estimated to range up to 100 times the average values. (author). 15 refs, 3 tabs

About fertility: a constant value or changing values for the replacement threshold?

Directory of Open Access Journals (Sweden)

Luigi Di Comite

2007-10-01

Full Text Available When we deal about fertility future evolution, it is generally believed – above all among people who do not deal with this topic – that in order to achieve an intrinsic rate of population natural increase equal to zero, able to ensure the constancy of its total amount over a long period (“zero population growth”, it is sufficient to reach a TFR equal, more or less, to 2.10 that must be kept steady in time having, as counterpart, fundamentally growing population for higher values and fundamentally decreasing population for values below the above mentioned level of reference (R=2.10. However, even nowadays, where the death rate is very high, in order to achieve an intrinsic rate of population natural increase equal to zero, it is necessary to start from total fertility rates, which are fundamentally as higher than 2.10 as higher is, at different ages, the mortality for women under 50. Under this consideration, we have pointed out the problem of singling out the so called replacement threshold of the TFR, assuming that it is not correct to interpret it as a fixed value, more or less equal to 2.10. In these pages we have briefly drawn – rather than demonstrated – the reader attention to the fact that for a TFR equal to 2.50 we have, considering the changes in mortality rates, values of net fertility rate which deeply vary, going from a value of 0.770 (for a life expectancy at birth equal to 20.0 years to a value of 2.426 (for a life expectancy at birth equal to 80 years as in the analysed case, and reaching a value which is very near to 2.100 for a life expectancy at birth equal to 62.5 years.

Varied line-space gratings: past, present and future

International Nuclear Information System (INIS)

Hettrick, M.C.

1985-08-01

A classically ruled diffraction grating consists of grooves which are equidistant, straight and parallel. Conversely, the so-called ''holographic'' grating (formed by the interfering waves of coherent visible light), although severely constrained by the recording wavelength and recording geometry, has grooves which are typically neither equidistant, straight nor parallel. In contrast, a varied line-space (VLS) grating, in common nomenclature, is a design in which the groove positions are relatively unconstrained yet possess sufficient symmetry to permit mechanical ruling. Such seemingly exotic gratings are no longer only a theoretical curiosity, but have been ruled and used in a wide variety of applications. These include: (1) aberration-corrected normal incidence concave gratings for Seya-Namioka monochromators and optical de-multiplexers, (2) flat-field grazing incidence concave gratings for plasma diagnostics, (3) aberration-corrected grazing incidence plane gratings for space-borne spectrometers, (4) focusing grazing incidence plane grating for synchrotron radiation monochromators, and (5) wavefront generators for visible interferometry of optical surfaces (particularly aspheres). Future prospects of VLS gratings as dispersing elements, wavefront correctors and beamsplitters appear promising. The author discusses the history of VLS gratings, their present applications, and their potential in the future. 61 refs., 24 figs

Adiponectin Concentrations: A Genome-wide Association Study

Science.gov (United States)

Jee, Sun Ha; Sull, Jae Woong; Lee, Jong-Eun; Shin, Chol; Park, Jongkeun; Kimm, Heejin; Cho, Eun-Young; Shin, Eun-Soon; Yun, Ji Eun; Park, Ji Wan; Kim, Sang Yeun; Lee, Sun Ju; Jee, Eun Jung; Baik, Inkyung; Kao, Linda; Yoon, Sungjoo Kim; Jang, Yangsoo; Beaty, Terri H.

2010-01-01

Adiponectin is associated with obesity and insulin resistance. To date, there has been no genome-wide association study (GWAS) of adiponectin levels in Asians. Here we present a GWAS of a cohort of Korean volunteers. A total of 4,001 subjects were genotyped by using a genome-wide marker panel in a two-stage design (979 subjects initially and 3,022 in a second stage). Another 2,304 subjects were used for follow-up replication studies with selected markers. In the discovery phase, the top SNP associated with mean log adiponectin was rs3865188 in CDH13 on chromosome 16 (p = 1.69 × 10−15 in the initial sample, p = 6.58 × 10−39 in the second genome-wide sample, and p = 2.12 × 10−32 in the replication sample). The meta-analysis p value for rs3865188 in all 6,305 individuals was 2.82 × 10−83. The association of rs3865188 with high-molecular-weight adiponectin (p = 7.36 × 10−58) was even stronger in the third sample. A reporter assay that evaluated the effects of a CDH13 promoter SNP in complete linkage disequilibrium with rs3865188 revealed that the major allele increased expression 2.2-fold. This study clearly shows that genetic variants in CDH13 influence adiponectin levels in Korean adults. PMID:20887962

Ozone formation in pulsed SDBD in a wide pressure range

Science.gov (United States)

Starikovskiy, Andrey; Nudnova, Maryia; mipt Team

2011-10-01

Ozone concentration in surface anode-directed DBD for wide pressure range (150 - 1300 torr) was experimentally measured. Voltage and pressure effect were investigated. Reduced electric field was measured for anode-directed and cathode-directed SDBD. E/n values in cathode-directed SDBD is higher than in cathode-directed on 50 percent at atmospheric pressure. E/n value increase leads to decrease the rate of oxygen dissociation and Ozone formation at lower pressures. Radiating region thickness of sliding discharge was measured. Typical thickness of radiating zone is 0.4-1.0 mm within pressure range 220-740 torr. It was shown that high-voltage pulsed nanosecond discharge due to high E/n value produces less Ozone with compare to other discharges. Kinetic model was proposed to describe Ozone formation in the pulsed nanosecond SDBD.

Tribological behavior and self-healing functionality of TiNbCN-Ag coatings in wide temperature range

Science.gov (United States)

Bondarev, A. V.; Kiryukhantsev-Korneev, Ph. V.; Levashov, E. A.; Shtansky, D. V.

2017-02-01

Ag- and Nb-doped TiCN coatings with about 2 at.% of Nb and Ag contents varied between 4.0 and 15.1 at.% were designed as promising materials for tribological applications in a wide temperature range. We report on the structure, mechanical, and tribological properties of TiNbCN-Ag coatings fabricated by simultaneous co-sputtering of TiC0.5 + 10%Nb2C and Ag targets in comparison with those of Ag-free coating. The tribological characteristics were evaluated during constant-temperature tests both at room temperature and 300 °C, as well as during dynamic temperature ramp tests in the range of 25-700 °C. The coating structure and elemental composition were studied by means of X-ray diffraction, scanning and transmission electron microscopy, and glow discharge optical emission spectroscopy. The coating microstructures and elemental compositions inside wear tracks, as well as the wear products, were examined by scanning electron microscopy, energy-dispersive spectroscopy, and Raman spectroscopy. We demonstrate that simultaneous alloying with Nb and Ag permits to overcome the main drawbacks of TiCN coatings such as their relatively high values of friction coefficient at elevated temperatures and low oxidation resistance. It is shown that a relatively high amount of Ag (15 at.%) is required to provide enhanced tribological behavior in a wide temperature range of 25-700 °C. In addition, the prepared Ag-doped coatings demonstrated active oxidation protection and self-healing functionality due to the segregation of Ag metallic particles in damage areas such as cracks, pin-holes, or oxidation sites.

Modelling tourists arrival using time varying parameter

Science.gov (United States)

Suciptawati, P.; Sukarsa, K. G.; Kencana, Eka N.

2017-06-01

The importance of tourism and its related sectors to support economic development and poverty reduction in many countries increase researchers’ attentions to study and model tourists’ arrival. This work is aimed to demonstrate time varying parameter (TVP) technique to model the arrival of Korean’s tourists to Bali. The number of Korean tourists whom visiting Bali for period January 2010 to December 2015 were used to model the number of Korean’s tourists to Bali (KOR) as dependent variable. The predictors are the exchange rate of Won to IDR (WON), the inflation rate in Korea (INFKR), and the inflation rate in Indonesia (INFID). Observing tourists visit to Bali tend to fluctuate by their nationality, then the model was built by applying TVP and its parameters were approximated using Kalman Filter algorithm. The results showed all of predictor variables (WON, INFKR, INFID) significantly affect KOR. For in-sample and out-of-sample forecast with ARIMA’s forecasted values for the predictors, TVP model gave mean absolute percentage error (MAPE) as much as 11.24 percent and 12.86 percent, respectively.

Value Judgements and Trade-Offs in Management of Nuclear Accidents: Using an Ethical Matrix in Practical Decision-Making

International Nuclear Information System (INIS)

Oughton, Deborah; Bay, Ingrid; Forsberg, Ellen-Marie; Kaiser, Matthias

2003-01-01

Experience after the Chernobyl accident has shown that restoration strategies need to consider a wide range of different issues to ensure the long-term sustainability of large and varied contaminated areas. Thus, the criteria by which we evaluate countermeasures needs to be extended from simple cost benefit effectiveness and radiological protection standards to a more integrated, holistic approach, including social and ethical aspects. Within the EU STRATEGY project, the applicability of many countermeasures is being critically assessed using a wide range of criteria, such as practicability, environmental side-effects, public perceptions of risk, communication and dialogue, and ethical aspects such as informed consent and the fair distribution of costs and doses. Although such socio-ethical factors are now the subject of a substantial field of research, there has been little attempt to integrate them in a practical context for decision makers. Within this paper, we suggest practical means by which these can be taken into account in the decision making process, proposing use of an ethical matrix to ensure transparent and systematic consideration of values in selection of a restoration strategy. in selection of a restoration strategy

In-plane impulse response of a curved bar with varying cross-section

International Nuclear Information System (INIS)

Suzuki, Katsuyoshi; Kosawada, Tadashi; Takahashi, Shin; Miyashita, Yasushi.

1984-01-01

The vibration problem of a curved bar, of which the center line is represented with a plane curve, is important for the aseismatic design of the piping system and structures in chemical and nuclear plants. The dynamic response problem of an in-plane curved bar has not been sufficiently examined. In this study, the in-plane impact response of an in-plane curved bar having varying cross section when impact load acts in the direction of the center of curvature was analyzed. First, the Lagrangian of a curved bar with varying cross section when general exciting distributed load acts in the direction of the center of curvature along the center line was determined by the classic theory, and from its stationary condition, the equations of motion and boundary conditions were derived. Next, the equations of motion were analyzed by eigen-function development method. In the example of numerical calculation, the variation of displacement and bending moment in course of time when stepwise concentrated impact load acts on a both ends fixed symmetric semi-elliptic arc bar was determined. Besides, the change of response due to the change of cross section and the change of the point of impact load application was clarified. Displacement and bending moment varied at a certain period with static value at the center. (Kako, I.)

Task 5. Grid interconnection of building integrated and other dispersed photovoltaic power systems. Grid-connected photovoltaic power systems: power value and capacity value of PV systems

Energy Technology Data Exchange (ETDEWEB)

Groppi, F.

2002-02-15

This report for the International Energy Agency (IEA) made by Task 5 of the Photovoltaic Power Systems (PVPS) programme takes a look at the power value and capacity value of photovoltaic power systems. The mission of the Photovoltaic Power Systems Programme is to enhance the international collaboration efforts which accelerate the development and deployment of photovoltaic solar energy. Task 5 deals with issues concerning grid-interconnection and dispersed PV power systems. This report summarises the results of a study aimed to assess the benefits that may be obtained when distributed PV production systems are present in a low-voltage grid. The basic aspects concerning the power-value and those related to the capacity-value are discussed. Data obtained from simulations are presented and discussed. A simple concept shows that great variation occurs if varying load patterns are taken into account. The power-value of PV generation in the grid varies instant by instant depending on the current level of power production and on the surrounding load conditions. Although the three case-studies considered do not cover all the possibilities of coupling between PV and loads, the results obtained show a good differentiation among users with PV production which leads to interesting conclusions.

Trade credit use and competition in the value chain : Evidence from Vietnam

NARCIS (Netherlands)

Hermes, Niels; Lensink, Robert; Lutz, Clemens; Thu, Uyen Nguyen Lam

2016-01-01

Trade credit is a major source of finance in value chains in developed and emerging economies. Despite its ubiquitous use, this is one of the first empirical studies that analyzes why the use of trade credit varies along the value chain. We argue that competition faced by firms at different stages

Factors influencing the robustness of P-value measurements in CT texture prognosis studies

Science.gov (United States)

McQuaid, Sarah; Scuffham, James; Alobaidli, Sheaka; Prakash, Vineet; Ezhil, Veni; Nisbet, Andrew; South, Christopher; Evans, Philip

2017-07-01

Several studies have recently reported on the value of CT texture analysis in predicting survival, although the topic remains controversial, with further validation needed in order to consolidate the evidence base. The aim of this study was to investigate the effect of varying the input parameters in the Kaplan-Meier analysis, to determine whether the resulting P-value can be considered to be a robust indicator of the parameter’s prognostic potential. A retrospective analysis of the CT-based normalised entropy of 51 patients with lung cancer was performed and overall survival data for these patients were collected. A normalised entropy cut-off was chosen to split the patient cohort into two groups and log-rank testing was performed to assess the survival difference of the two groups. This was repeated for varying normalised entropy cut-offs and varying follow-up periods. Our findings were also compared with previously published results to assess robustness of this parameter in a multi-centre patient cohort. The P-value was found to be highly sensitive to the choice of cut-off value, with small changes in cut-off producing substantial changes in P. The P-value was also sensitive to follow-up period, with particularly noisy results at short follow-up periods. Using matched conditions to previously published results, a P-value of 0.162 was obtained. Survival analysis results can be highly sensitive to the choice in texture cut-off value in dichotomising patients, which should be taken into account when performing such studies to avoid reporting false positive results. Short follow-up periods also produce unstable results and should therefore be avoided to ensure the results produced are reproducible. Previously published findings that indicated the prognostic value of normalised entropy were not replicated here, but further studies with larger patient numbers would be required to determine the cause of the different outcomes.

Separate populations of neurons in ventral striatum encode value and motivation.

Science.gov (United States)

Bissonette, Gregory B; Burton, Amanda C; Gentry, Ronny N; Goldstein, Brandon L; Hearn, Taylor N; Barnett, Brian R; Kashtelyan, Vadim; Roesch, Matthew R

2013-01-01

Neurons in the ventral striatum (VS) fire to cues that predict differently valued rewards. It is unclear whether this activity represents the value associated with the expected reward or the level of motivation induced by reward anticipation. To distinguish between the two, we trained rats on a task in which we varied value independently from motivation by manipulating the size of the reward expected on correct trials and the threat of punishment expected upon errors. We found that separate populations of neurons in VS encode expected value and motivation.

Errors in 'BED'-derived estimates of HIV incidence will vary by place, time and age.

Directory of Open Access Journals (Sweden)

Timothy B Hallett

2009-05-01

Full Text Available The BED Capture Enzyme Immunoassay, believed to distinguish recent HIV infections, is being used to estimate HIV incidence, although an important property of the test--how specificity changes with time since infection--has not been not measured.We construct hypothetical scenarios for the performance of BED test, consistent with current knowledge, and explore how this could influence errors in BED estimates of incidence using a mathematical model of six African countries. The model is also used to determine the conditions and the sample sizes required for the BED test to reliably detect trends in HIV incidence.If the chance of misclassification by BED increases with time since infection, the overall proportion of individuals misclassified could vary widely between countries, over time, and across age-groups, in a manner determined by the historic course of the epidemic and the age-pattern of incidence. Under some circumstances, changes in BED estimates over time can approximately track actual changes in incidence, but large sample sizes (50,000+ will be required for recorded changes to be statistically significant.The relationship between BED test specificity and time since infection has not been fully measured, but, if it decreases, errors in estimates of incidence could vary by place, time and age-group. This means that post-assay adjustment procedures using parameters from different populations or at different times may not be valid. Further research is urgently needed into the properties of the BED test, and the rate of misclassification in a wide range of populations.

Frequency of low-value care in Alberta, Canada: a retrospective cohort study.

Science.gov (United States)

McAlister, Finlay A; Lin, Meng; Bakal, Jeff; Dean, Stafford

2018-05-01

To determine how frequently 10 low-value services highlighted by Choosing Wisely are done and what factors influence their provision. This is a retrospective cohort study using routinely collected health data from five linked data sets from 2012 to 2015 in the Canadian province of Alberta to determine the frequency with which 10 low-value services were provided. Between 2012 and 2015, 162 143 people (4% of all 3 814 536 adult Albertans and 5% of the 3  423 135 who saw a physician at least once in that time frame) received at least one of the 10 low-value services, including 29.8% of Albertans older than 75 years (57 811 of 194 068). The proportion of adults receiving low-value services ranged from carotid artery imaging in 0.1% of asymptomatic adults without cerebrovascular disease, to prostate-specific antigen (PSA) testing in 55.5% of men 75 years or older without a history of prostate cancer. Although age, Charlson scores and frequency of primary care visits were associated with low-value service provision, the directions of the association differed across services; however, higher socioeconomic status, increased frequency of specialist contact and higher ratio of specialists to primary care physicians in the patient's region were associated with an increased risk of receiving all of the low-value services we examined. The low-value services which resulted in the greatest costs to the healthcare system were cervical cancer screening in women older than 65 without history of cervical dysplasia or genital cancer, PSA testing in men older than 75 without history of prostate cancer and preoperative stress testing/cardiac imaging before non-cardiac surgery. Even within a universal coverage healthcare system, the proportion of patients receiving low-value services varied widely (from <0.1% to 56%). Increased use was associated with higher socioeconomic status, increased frequency of specialist contact and higher ratio of specialists to primary care

Environmental Reporting for Global Higher Education Institutions using the World Wide Web.

Science.gov (United States)

Walton, J.; Alabaster, T.; Richardson, S.; Harrison, R.

1997-01-01

Proposes the value of voluntary environmental reporting by higher education institutions as an aid to implementing environmental policies. Suggests that the World Wide Web can provide a fast, up-to-date, flexible, participatory, multidimensional medium for information exchange and management. Contains 29 references. (PVD)

Pathogen exposure varies widely among sympatric populations of wild and domestic felids across the United States.

Science.gov (United States)

Carver, Scott; Bevins, Sarah N; Lappin, Michael R; Boydston, Erin E; Lyren, Lisa M; Alldredge, Mathew; Logan, Kenneth A; Sweanor, Linda L; Riley, Seth P D; Serieys, Laurel E K; Fisher, Robert N; Vickers, T Winston; Boyce, Walter; Mcbride, Roy; Cunningham, Mark C; Jennings, Megan; Lewis, Jesse; Lunn, Tamika; Crooks, Kevin R; Vandewoude, Sue

2016-03-01

Understanding how landscape, host, and pathogen traits contribute to disease exposure requires systematic evaluations of pathogens within and among host species and geographic regions. The relative importance of these attributes is critical for management of wildlife and mitigating domestic animal and human disease, particularly given rapid ecological changes, such as urbanization. We screened > 1000 samples from sympatric populations of puma (Puma concolor), bobcat (Lynx rufus), and domestic cat (Felis catus) across urban gradients in six sites, representing three regions, in North America for exposure to a representative suite of bacterial, protozoal, and viral pathogens (Bartonella sp., Toxoplasma gondii, feline herpesvirus-1, feline panleukopenea virus, feline calicivirus, and feline immunodeficiency virus). We evaluated prevalence within each species, and examined host trait and land cover determinants of exposure; providing an unprecedented analysis of factors relating to potential for infections in domesticated and wild felids. Prevalence differed among host species (highest for puma and lowest for domestic cat) and was greater for indirectly transmitted pathogens. Sex was inconsistently predictive of exposure to directly transmitted pathogens only, and age infrequently predictive of both direct and indirectly transmitted pathogens. Determinants of pathogen exposure were widely divergent between the wild felid species. For puma, suburban land use predicted increased exposure to Bartonella sp. in southern California, and FHV-1 exposure increased near urban edges in Florida. This may suggest interspecific transmission with domestic cats via flea vectors (California) and direct contact (Florida) around urban boundaries. Bobcats captured near urban areas had increased exposure to T. gondii in Florida, suggesting an urban source of prey Bobcats captured near urban areas in Colorado and Florida had higher FIV exposure, possibly suggesting increased intraspecific

Pathogen exposure varies widely among sympatric populations of wild and domestic felids across the United States

Science.gov (United States)

Carver, Scott; Bevins, Sarah N.; Lappin, Michael R.; Boydston, Erin E.; Lyren, Lisa M.; Alldredge, Mathew W.; Logan, Kenneth A.; Sweanor, Linda L.; Riley, Seth P.D.; Serieys, Laurel E.K.; Fisher, Robert N.; Vickers, T. Winston; Boyce, Walter M.; McBride, Roy; Cunnigham, Mark C.; Jennings, Megan; Lewis, Jesse S.; Lunn, Tamika; Crooks, Kevin R.; VandeWoude, Sue

2016-01-01

Understanding how landscape, host, and pathogen traits contribute to disease exposure requires systematic evaluations of pathogens within and among host species and geographic regions. The relative importance of these attributes is critical for management of wildlife and mitigating domestic animal and human disease, particularly given rapid ecological changes, such as urbanization. We screened >1,000 samples from sympatric populations of puma (Puma concolor), bobcat (Lynx rufus) and domestic cat (Felis catus) across urban gradients in six sites, representing three regions, in North America for exposure to a representative suite of bacterial, protozoal and viral pathogens (Bartonella sp., Toxoplasma gondii, feline herpesvirus-1, feline panleukopenea virus, feline calicivirus, feline immunodeficiency virus). We evaluated prevalence within each species, and examined host trait and land cover determinants of exposure-providing an unprecedented analysis of factors relating to potential for infections in domesticated and wild felids. Prevalence differed among host species (highest for puma and lowest for domestic cat) and was greater for indirectly transmitted pathogens. Sex was inconsistently predictive of exposure to directly transmitted pathogens only, and age infrequently predictive of both direct and indirectly transmitted pathogens. Determinants of pathogen exposure were widely divergent between the wild felid species. For puma, suburban landuse predicted increased exposure to Bartonella sp. in southern California, and FHV-1 exposure increased near urban edges in Florida. This may suggest inter-specific transmission with domestic cats via flea vectors (California) and direct contact (Florida) around urban boundaries. Bobcats captured near urban areas had increased exposure to T. gondii in Florida, suggesting an urban source of prey. Bobcats captured near urban areas in Colorado and Florida had higher FIV exposure, possibly suggesting increased intra

Brain metastasis from melanoma: the prognostic value of varying sites of extracranial disease.

Science.gov (United States)

Bates, James E; Youn, Paul; Usuki, Kenneth Y; Walter, Kevin A; Huggins, Christine F; Okunieff, Paul; Milano, Michael T

2015-11-01

Patients with brain metastasis from melanoma have poor outcomes. Radiation is used both for prognostic and symptomatic value. We aimed to further clarify the role of stereotactic radiosurgery (SRS) and whole brain radiotherapy (WBRT) as well as the prognostic implication of various sites of extracranial disease. The records of 73 consecutive patients treated at the University of Rochester Medical Center for brain-metastatic melanoma from January 2004 to October 2013 were reviewed. The median overall survival (OS) was 3.0 months. Patients treated with WBRT alone had decreased OS compared to those treated with SRS alone (HR = 0.38, p = 0.001) or WBRT and SRS (HR = 0.51, p = 0.039). The mean number of brain metastasis differed (p = 0.002) in patients in patients who received WBRT (4.0) compared to those who did not (2.0). Among patients with extracranial disease (n = 63), bone metastasis (HR = 1.86, p = 0.047, n = 15) was a negative prognostic factor; liver (HR = 1.59, p = 0.113, n = 17), lung (HR = 1.51, p = 0.23, n = 51) and adrenal metastasis (HR = 1.70, p = 0.15, n = 10) were not. In patients with concurrent brain and lung metastasis, those with disease limited to those two sites (OS = 8.7 mo, n = 13) had improved OS (HR = 0.44, p = 0.014) compared to those with additional disease (OS = 1.8 mo, n = 50). Based on this hypothesis-generating retrospective analysis, SRS may offer survival benefit compared to WBRT alone in patients with brain metastatic melanoma. Bone metastasis appears to confer a particularly poor prognosis. Those with disease confined to the lung and brain may represent a population with improved prognosis.

Wide-Range Probing of Dzyaloshinskii-Moriya Interaction

Science.gov (United States)

Kim, Duck-Ho; Yoo, Sang-Cheol; Kim, Dae-Yun; Min, Byoung-Chul; Choe, Sug-Bong

2017-03-01

The Dzyaloshinskii-Moriya interaction (DMI) in magnetic objects is of enormous interest, because it generates built-in chirality of magnetic domain walls (DWs) and topologically protected skyrmions, leading to efficient motion driven by spin-orbit torques. Because of its importance for both potential applications and fundamental research, many experimental efforts have been devoted to DMI investigation. However, current experimental probing techniques cover only limited ranges of the DMI strength and have specific sample requirements. Thus, there are no versatile methods to quantify DMI over a wide range of values. Here, we present such an experimental scheme, which is based on the angular dependence of asymmetric DW motion. This method can be used to determine values of DMI much larger than the maximum strength of the external magnetic field strength, which demonstrates that various DMI strengths can be quantified with a single measurement setup. This scheme may thus prove essential to DMI-related emerging fields in nanotechnology.

Signal intensity changes of normal brain at varying high b-value diffusion-weighted images using 3.0T MR scanner

International Nuclear Information System (INIS)

Lee, Jin Hee; Sohn, Chul Ho; Choi, Jin Soo

2003-01-01

Using diffusion-weighted MR imaging (DWI), to evaluate the signal intensity characteristics of normal adult brain as diffusion gradient strength (b value) increases from 1,000 to 3,000 s/mm 2 . Twenty-one healthy volunteers with neither neurologic symptoms nor pathologic findings at axial and sagittal T2-weighted MR imaging were involved in this study. All images were obtained with a 3.0T MR scanner. Six sets of spin-echo echo-planar images were acquired in the axial plane using progressively increasing strengths of diffusion-sensitizing gradients (corresponding to b values of 0, 1,000, 1,500, 2,000, 2,500, and 3,000 s/mm 2 ). All imaging parameters other than TE remained constant. Changes in normal white-gray matter signal intensity observed at variable b-value DWI were qualitatively analysed, and the signal-to-noise ratios (SNRs) in six anatomic regions (frontal and parietal white matter, genu and splenium corporis callosi, the posterior limb of the internal capsule, and the thalamus) quantitatively, and the ratios were averaged and compared with the average SNR of 1,000 s/mm DWI. As gradient strength increased from 1,000 to 3,000 s/mm 2 , both gray-and white-matter structures diminished in signal intensity, and images obtained at a b value of 3,000 s/mm 2 appeared very noisy. White matter became progressively hyperintense to gray matter as the diffusion sensitizing gradient increased, especially at the centrum semiovale, the posterior limb of the internal capsule, and the splenium corporis callosi, but the genu corporis callosi; showed exceptional intermediate low signal intensity. At quantitative assessment, the signal-to-noise ratio decreased as the diffusion sensitizing gradient increased. Relative to the images obtained at a b value of 1,000 s/mm 2 , average SNRs were 0.71 (b=1,500 s/mm 2 ), 0.52 (b=2,000 s/mm 2 ), 0.41 (b=2,500 s/mm 2 ), 0.33 (b=3,000 s/mm 2 ). As the diffusion sensitizing gradient increased, the signal-to-noise ratio of brain structures

Creatine and guanidinoacetate reference values in a French population

NARCIS (Netherlands)

Joncquel-Cheval Curt, M.; Cheillan, D.; Briand, G.; Salomons, G.S.; Mention-Mulliez, K.; Dobbelaere, D.; Cuisset, J.M.; Lion-Francois, L.; Portes, V.D.; Chabli, A.; Valayannopoulos, V.; Benoist, J.F.; Pinard, J.M.; Simard, G.; Douay, O.; Deiva, K.; Tardieu, M.; Afenjar, A.; Heron, D.; Rivier, F.; Chabrol, B.; Prieur, F.; Cartault, F.; Pitelet, G.; Goldenberg, A.; Bekri, S.; Gerard, M.; Delorme, R.; Porchet, N.; Vianey-Saban, C.; Vamecq, J.

2013-01-01

Creatine and guanidinoacetate are biomarkers of creatine metabolism. Their assays in body fluids may be used for detecting patients with primary creatine deficiency disorders (PCDD), a class of inherited diseases. Their laboratory values in blood and urine may vary with age, requiring that reference

Effects of Temporal Wind Patterns on the Value of Wind-Generated Electricity in California and the Northwest

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ryan H; Wiser, Ryan H; Fripp, Matthias

2008-05-01

Wind power production is variable, but also has diurnal and seasonal patterns. These patterns differ between sites, potentially making electric power from some wind sites more valuable for meeting customer loads or selling in wholesale power markets. This paper investigates whether the timing of wind significantly affects the value of electricity from sites in California and the Northwestern United States. We use both measured and modeled wind data and estimate the time-varying value of wind power with both financial and load-based metrics. We find that the potential difference in wholesale market value between better-correlated and poorly correlated wind sites is modest, on the order of 5-10 percent. A load-based metric, power production during the top 10 percent of peak load hours, varies more strongly between sites, suggesting that the capacity value of different wind projects could vary by as much as 50 percent based on the timing of wind alone.

Genome-wide association of lipid-lowering response to statins in combined study populations.

Directory of Open Access Journals (Sweden)

Mathew J Barber

2010-03-01

Full Text Available Statins effectively lower total and plasma LDL-cholesterol, but the magnitude of decrease varies among individuals. To identify single nucleotide polymorphisms (SNPs contributing to this variation, we performed a combined analysis of genome-wide association (GWA results from three trials of statin efficacy.Bayesian and standard frequentist association analyses were performed on untreated and statin-mediated changes in LDL-cholesterol, total cholesterol, HDL-cholesterol, and triglyceride on a total of 3932 subjects using data from three studies: Cholesterol and Pharmacogenetics (40 mg/day simvastatin, 6 weeks, Pravastatin/Inflammation CRP Evaluation (40 mg/day pravastatin, 24 weeks, and Treating to New Targets (10 mg/day atorvastatin, 8 weeks. Genotype imputation was used to maximize genomic coverage and to combine information across studies. Phenotypes were normalized within each study to account for systematic differences among studies, and fixed-effects combined analysis of the combined sample were performed to detect consistent effects across studies. Two SNP associations were assessed as having posterior probability greater than 50%, indicating that they were more likely than not to be genuinely associated with statin-mediated lipid response. SNP rs8014194, located within the CLMN gene on chromosome 14, was strongly associated with statin-mediated change in total cholesterol with an 84% probability by Bayesian analysis, and a p-value exceeding conventional levels of genome-wide significance by frequentist analysis (P = 1.8 x 10(-8. This SNP was less significantly associated with change in LDL-cholesterol (posterior probability = 0.16, P = 4.0 x 10(-6. Bayesian analysis also assigned a 51% probability that rs4420638, located in APOC1 and near APOE, was associated with change in LDL-cholesterol.Using combined GWA analysis from three clinical trials involving nearly 4,000 individuals treated with simvastatin, pravastatin, or atorvastatin, we

Microbial production of value-added nutraceuticals.

Science.gov (United States)

Wang, Jian; Guleria, Sanjay; Koffas, Mattheos Ag; Yan, Yajun

2016-02-01

Nutraceuticals are important natural bioactive compounds that confer health-promoting and medical benefits to humans. Globally growing demands for value-added nutraceuticals for prevention and treatment of human diseases have rendered nutraceuticals a multi-billion dollar market. However, supply limitations and extraction difficulties from natural sources such as plants, animals or fungi, restrict the large-scale use of nutraceuticals. Metabolic engineering via microbial production platforms has been advanced as an eco-friendly alternative approach for production of value-added nutraceuticals from simple carbon sources. Microbial platforms like the most widely used Escherichia coli and Saccharomyces cerevisiae have been engineered as versatile cell factories for production of diverse and complex value-added chemicals such as phytochemicals, prebiotics, polysaccaharides and poly amino acids. This review highlights the recent progresses in biological production of value-added nutraceuticals via metabolic engineering approaches. Copyright © 2015 Elsevier Ltd. All rights reserved.

Complex-valued neural networks advances and applications

CERN Document Server

Hirose, Akira

2013-01-01

Presents the latest advances in complex-valued neural networks by demonstrating the theory in a wide range of applications Complex-valued neural networks is a rapidly developing neural network framework that utilizes complex arithmetic, exhibiting specific characteristics in its learning, self-organizing, and processing dynamics. They are highly suitable for processing complex amplitude, composed of amplitude and phase, which is one of the core concepts in physical systems to deal with electromagnetic, light, sonic/ultrasonic waves as well as quantum waves, namely, electron and

Statistical analysis of the distribution of critical current and the correlation of n value to the critical current of bent Bi2223 composite tape

International Nuclear Information System (INIS)

Ochiai, S; Matsubayashi, H; Okuda, H; Osamura, K; Otto, A; Malozemoff, A

2009-01-01

Distributions of local and overall critical currents and correlation of n value to the critical current of bent Bi2223 composite tape were studied from the statistical viewpoint. The data of the local and overall transport critical currents and n values of the Bi2223 composite tape specimens were collected experimentally for a wide range of bending strain (0-1.1%) by using the specimens, designed so as to characterize the local and overall critical currents and n values. The measured local and overall critical currents were analyzed with various types of Weibull distribution function. Which of the Weibull distribution functions is suitable for the description of the distribution of local and overall critical currents at each bending strain, and also how much the Weibull parameter values characterizing the distribution vary with bending strain, were revealed. Then we attempted to reproduce the overall critical current distribution and correlation of the overall n value to the overall critical current from the distribution of local critical currents and the correlation of the local n value to the local critical current by a Monte Carlo simulation. The measured average values of critical current and n value at each bending strain and the correlation of n value to critical current were reproduced well by the present simulation, while the distribution of critical current values was reproduced fairly well but not fully. The reason for this is discussed.

The limit distribution of the maximum increment of a random walk with regularly varying jump size distribution

DEFF Research Database (Denmark)

Mikosch, Thomas Valentin; Rackauskas, Alfredas

2010-01-01

In this paper, we deal with the asymptotic distribution of the maximum increment of a random walk with a regularly varying jump size distribution. This problem is motivated by a long-standing problem on change point detection for epidemic alternatives. It turns out that the limit distribution...... of the maximum increment of the random walk is one of the classical extreme value distributions, the Fréchet distribution. We prove the results in the general framework of point processes and for jump sizes taking values in a separable Banach space...

Medication and volume delivery by gravity-driven micro-drip intravenous infusion: potential variations during "wide-open" flow.

Science.gov (United States)

Pierce, Eric T; Kumar, Vikram; Zheng, Hui; Peterfreund, Robert A

2013-03-01

Gravity-driven micro-drip infusion sets allow control of medication dose delivery by adjusting drops per minute. When the roller clamp is fully open, flow in the drip chamber can be a continuous fluid column rather than discrete, countable, drops. We hypothesized that during this "wide-open" state, drug delivery becomes dependent on factors extrinsic to the micro-drip set and is therefore difficult to predict. We conducted laboratory experiments to characterize volume delivery under various clinically relevant conditions of wide-open flow in an in vitro laboratory model. A micro-drip infusion set, plugged into a bag of normal saline, was connected to a high-flow stopcock at the distal end. Vertically oriented IV catheters (gauges 14-22) were connected to the stopcock. The fluid meniscus height in the bag was fixed (60-120 cm) above the outflow point. The roller clamp on the infusion set was in fully open position for all experiments resulting in a continuous column of fluid in the drip chamber. Fluid volume delivered in 1 minute was measured 4 times with each condition. To model resistive effects of carrier flow, volumetric infusion pumps were used to deliver various flow rates of normal saline through a carrier IV set into which a micro-drip infusion was "piggybacked." We also compared delivery by micro-drip infusion sets from 3 manufacturers. The volume of fluid delivered by gravity-driven infusion under wide-open conditions (continuous fluid column in drip chamber) varied 2.9-fold (95% confidence interval, 2.84-2.96) depending on catheter size and fluid column height. Total model resistance of the micro-drip with stopcock and catheter varied with flow rate. Volume delivered by the piggybacked micro-drip decreased up to 29.7% ± 0.8% (mean ± SE) as the carrier flow increased from 0 to 1998 mL/min. Delivery characteristics of the micro-drip infusion sets from 3 different manufacturers were similar. Laboratory simulation of clinical situations with gravity

Genome-wide significant locus for Research Diagnostic Criteria Schizoaffective Disorder Bipolar type.

Science.gov (United States)

Green, Elaine K; Di Florio, Arianna; Forty, Liz; Gordon-Smith, Katherine; Grozeva, Detelina; Fraser, Christine; Richards, Alexander L; Moran, Jennifer L; Purcell, Shaun; Sklar, Pamela; Kirov, George; Owen, Michael J; O'Donovan, Michael C; Craddock, Nick; Jones, Lisa; Jones, Ian R

2017-12-01

Studies have suggested that Research Diagnostic Criteria for Schizoaffective Disorder Bipolar type (RDC-SABP) might identify a more genetically homogenous subgroup of bipolar disorder. Aiming to identify loci associated with RDC-SABP, we have performed a replication study using independent RDC-SABP cases (n = 144) and controls (n = 6,559), focusing on the 10 loci that reached a p-value bipolar disorder sample. Combining the WTCCC and replication datasets by meta-analysis (combined RDC-SABP, n = 423, controls, n = 9,494), we observed genome-wide significant association at one SNP, rs2352974, located within the intron of the gene TRAIP on chromosome 3p21.31 (p-value, 4.37 × 10 -8 ). This locus did not reach genome-wide significance in bipolar disorder or schizophrenia large Psychiatric Genomic Consortium datasets, suggesting that it may represent a relatively specific genetic risk for the bipolar subtype of schizoaffective disorder. © 2017 Wiley Periodicals, Inc.

Invariant operator theory for the single-photon energy in time-varying media

International Nuclear Information System (INIS)

Jeong-Ryeol, Choi

2010-01-01

After the birth of quantum mechanics, the notion in physics that the frequency of light is the only factor that determines the energy of a single photon has played a fundamental role. However, under the assumption that the theory of Lewis–Riesenfeld invariants is applicable in quantum optics, it is shown in the present work that this widely accepted notion is valid only for light described by a time-independent Hamiltonian, i.e., for light in media satisfying the conditions, ε(i) = ε(0), μ(t) = μ(0), and σ(t) = 0 simultaneously. The use of the Lewis–Riesenfeld invariant operator method in quantum optics leads to a marvelous result: the energy of a single photon propagating through time-varying linear media exhibits nontrivial time dependence without a change of frequency. (general)

Online Support Vector Regression with Varying Parameters for Time-Dependent Data

International Nuclear Information System (INIS)

Omitaomu, Olufemi A.; Jeong, Myong K.; Badiru, Adedeji B.

2011-01-01

Support vector regression (SVR) is a machine learning technique that continues to receive interest in several domains including manufacturing, engineering, and medicine. In order to extend its application to problems in which datasets arrive constantly and in which batch processing of the datasets is infeasible or expensive, an accurate online support vector regression (AOSVR) technique was proposed. The AOSVR technique efficiently updates a trained SVR function whenever a sample is added to or removed from the training set without retraining the entire training data. However, the AOSVR technique assumes that the new samples and the training samples are of the same characteristics; hence, the same value of SVR parameters is used for training and prediction. This assumption is not applicable to data samples that are inherently noisy and non-stationary such as sensor data. As a result, we propose Accurate On-line Support Vector Regression with Varying Parameters (AOSVR-VP) that uses varying SVR parameters rather than fixed SVR parameters, and hence accounts for the variability that may exist in the samples. To accomplish this objective, we also propose a generalized weight function to automatically update the weights of SVR parameters in on-line monitoring applications. The proposed function allows for lower and upper bounds for SVR parameters. We tested our proposed approach and compared results with the conventional AOSVR approach using two benchmark time series data and sensor data from nuclear power plant. The results show that using varying SVR parameters is more applicable to time dependent data.

Time-varying risk aversion. An application to energy hedging

Energy Technology Data Exchange (ETDEWEB)

Cotter, John [Centre for Financial Markets, School of Business, University College Dublin, Blackrock, Co. Dublin (Ireland); Hanly, Jim [School of Accounting and Finance, Dublin Institute of Technology, Dublin 2 (Ireland)

2010-03-15

Risk aversion is a key element of utility maximizing hedge strategies; however, it has typically been assigned an arbitrary value in the literature. This paper instead applies a GARCH-in-Mean (GARCH-M) model to estimate a time-varying measure of risk aversion that is based on the observed risk preferences of energy hedging market participants. The resulting estimates are applied to derive explicit risk aversion based optimal hedge strategies for both short and long hedgers. Out-of-sample results are also presented based on a unique approach that allows us to forecast risk aversion, thereby estimating hedge strategies that address the potential future needs of energy hedgers. We find that the risk aversion based hedges differ significantly from simpler OLS hedges. When implemented in-sample, risk aversion hedges for short hedgers outperform the OLS hedge ratio in a utility based comparison. (author)

Time-varying risk aversion. An application to energy hedging

International Nuclear Information System (INIS)

Cotter, John; Hanly, Jim

2010-01-01

Risk aversion is a key element of utility maximizing hedge strategies; however, it has typically been assigned an arbitrary value in the literature. This paper instead applies a GARCH-in-Mean (GARCH-M) model to estimate a time-varying measure of risk aversion that is based on the observed risk preferences of energy hedging market participants. The resulting estimates are applied to derive explicit risk aversion based optimal hedge strategies for both short and long hedgers. Out-of-sample results are also presented based on a unique approach that allows us to forecast risk aversion, thereby estimating hedge strategies that address the potential future needs of energy hedgers. We find that the risk aversion based hedges differ significantly from simpler OLS hedges. When implemented in-sample, risk aversion hedges for short hedgers outperform the OLS hedge ratio in a utility based comparison. (author)

Adding Value to Customers and Developing Brands through Electronic Newsletters

Directory of Open Access Journals (Sweden)

Alexandra ZBUCHEA

2013-12-01

Full Text Available Online communication is highly efficient for contemporary business, in most market sectors. In this context, companies use several online instruments in order to achieve a wide array of objectives. Among these, online newsletters (e-newsletters are widely used, since they offer a lot of benefits for companies. Since they are flexible in terms of format and content, they are suitable to address a wide variety of publics. Therefore, e-newsletters could be not just informative (as they are widely seen, but also could add-value to customers and support branding processes and relationship development. The present paper investigated various benefits of e-newsletters in this context and highlights some rules to ensure an effective added-value e-newsletter. The research made on the e-newsletters of 5 of the leading publishing-houses in Romania shows that, at least in this market sector, this instrument is not used at its full potential. It is considered in most cases a way to stimulate sales, either directly by announcing sales, or indirectly by announcing new books releases. In some cases news on events and on the activity of the publishing-houses are presenting, leading to image development.

Stochastic analysis of epidemics on adaptive time varying networks

Science.gov (United States)

Kotnis, Bhushan; Kuri, Joy

2013-06-01

Many studies investigating the effect of human social connectivity structures (networks) and human behavioral adaptations on the spread of infectious diseases have assumed either a static connectivity structure or a network which adapts itself in response to the epidemic (adaptive networks). However, human social connections are inherently dynamic or time varying. Furthermore, the spread of many infectious diseases occur on a time scale comparable to the time scale of the evolving network structure. Here we aim to quantify the effect of human behavioral adaptations on the spread of asymptomatic infectious diseases on time varying networks. We perform a full stochastic analysis using a continuous time Markov chain approach for calculating the outbreak probability, mean epidemic duration, epidemic reemergence probability, etc. Additionally, we use mean-field theory for calculating epidemic thresholds. Theoretical predictions are verified using extensive simulations. Our studies have uncovered the existence of an “adaptive threshold,” i.e., when the ratio of susceptibility (or infectivity) rate to recovery rate is below the threshold value, adaptive behavior can prevent the epidemic. However, if it is above the threshold, no amount of behavioral adaptations can prevent the epidemic. Our analyses suggest that the interaction patterns of the infected population play a major role in sustaining the epidemic. Our results have implications on epidemic containment policies, as awareness campaigns and human behavioral responses can be effective only if the interaction levels of the infected populace are kept in check.

Uncertainty in Forest Net Present Value Estimations

Directory of Open Access Journals (Sweden)

Ilona Pietilä

2010-09-01

Full Text Available Uncertainty related to inventory data, growth models and timber price fluctuation was investigated in the assessment of forest property net present value (NPV. The degree of uncertainty associated with inventory data was obtained from previous area-based airborne laser scanning (ALS inventory studies. The study was performed, applying the Monte Carlo simulation, using stand-level growth and yield projection models and three alternative rates of interest (3, 4 and 5%. Timber price fluctuation was portrayed with geometric mean-reverting (GMR price models. The analysis was conducted for four alternative forest properties having varying compartment structures: (A a property having an even development class distribution, (B sapling stands, (C young thinning stands, and (D mature stands. Simulations resulted in predicted yield value (predicted NPV distributions at both stand and property levels. Our results showed that ALS inventory errors were the most prominent source of uncertainty, leading to a 5.1–7.5% relative deviation of property-level NPV when an interest rate of 3% was applied. Interestingly, ALS inventory led to significant biases at the property level, ranging from 8.9% to 14.1% (3% interest rate. ALS inventory-based bias was the most significant in mature stand properties. Errors related to the growth predictions led to a relative standard deviation in NPV, varying from 1.5% to 4.1%. Growth model-related uncertainty was most significant in sapling stand properties. Timber price fluctuation caused the relative standard deviations ranged from 3.4% to 6.4% (3% interest rate. The combined relative variation caused by inventory errors, growth model errors and timber price fluctuation varied, depending on the property type and applied rates of interest, from 6.4% to 12.6%. By applying the methodology described here, one may take into account the effects of various uncertainty factors in the prediction of forest yield value and to supply the

Boundary Value Problems Arising in Kalman Filtering

Directory of Open Access Journals (Sweden)

Sinem Ertürk

2009-01-01

Full Text Available The classic Kalman filtering equations for independent and correlated white noises are ordinary differential equations (deterministic or stochastic with the respective initial conditions. Changing the noise processes by taking them to be more realistic wide band noises or delayed white noises creates challenging partial differential equations with initial and boundary conditions. In this paper, we are aimed to give a survey of this connection between Kalman filtering and boundary value problems, bringing them into the attention of mathematicians as well as engineers dealing with Kalman filtering and boundary value problems.

Boundary Value Problems Arising in Kalman Filtering

Directory of Open Access Journals (Sweden)

Bashirov Agamirza

2008-01-01

Full Text Available The classic Kalman filtering equations for independent and correlated white noises are ordinary differential equations (deterministic or stochastic with the respective initial conditions. Changing the noise processes by taking them to be more realistic wide band noises or delayed white noises creates challenging partial differential equations with initial and boundary conditions. In this paper, we are aimed to give a survey of this connection between Kalman filtering and boundary value problems, bringing them into the attention of mathematicians as well as engineers dealing with Kalman filtering and boundary value problems.

Review of stellarator research world wide

International Nuclear Information System (INIS)

Shonet, J.L.

1987-01-01

The world-wide effort in stellarators has evolved considerably during the past few years. Stellarator facilities are located in the Australia, Federal Republic of Germany, Japan, the Soviet Union, Spain, the United Kingdom and the United States. Dimensions of stellarators range from less than 20 centimeters in major radius to more than 2 meters, and magnetic field values between 0.2 Tesla to more than 3.0 Tesla. Stellarators are made in a variety of magnetic configurations with wide ranges of toroidal aspect ratios and methods of generating the stellarator magnetic surfaces. In particular, continuous helical coils, twisted modular coils, or twisted vacuum chambers all provide different means to generate nested toroidal magnetic surfaces without the need for currents flowing in the plasma. The goal of present day experiments is to accumulate a physics data base. This is being done by increasing electron and ion temperatures with non-ohmic heating, by transport and scaling studies considering neoclassical scaling, global scaling, effects of electric fields, the bootstrap current and magnetic islands. Higher betas are being attempted by designing suitable magnetic configurations, pellet injection and/or minimizing transport losses. Plasma-wall interactions and particle control are being examined by divertor, pumped-limiter and carbonization experiments

Collateral missing value imputation: a new robust missing value estimation algorithm for microarray data.

Science.gov (United States)

Sehgal, Muhammad Shoaib B; Gondal, Iqbal; Dooley, Laurence S

2005-05-15

Microarray data are used in a range of application areas in biology, although often it contains considerable numbers of missing values. These missing values can significantly affect subsequent statistical analysis and machine learning algorithms so there is a strong motivation to estimate these values as accurately as possible before using these algorithms. While many imputation algorithms have been proposed, more robust techniques need to be developed so that further analysis of biological data can be accurately undertaken. In this paper, an innovative missing value imputation algorithm called collateral missing value estimation (CMVE) is presented which uses multiple covariance-based imputation matrices for the final prediction of missing values. The matrices are computed and optimized using least square regression and linear programming methods. The new CMVE algorithm has been compared with existing estimation techniques including Bayesian principal component analysis imputation (BPCA), least square impute (LSImpute) and K-nearest neighbour (KNN). All these methods were rigorously tested to estimate missing values in three separate non-time series (ovarian cancer based) and one time series (yeast sporulation) dataset. Each method was quantitatively analyzed using the normalized root mean square (NRMS) error measure, covering a wide range of randomly introduced missing value probabilities from 0.01 to 0.2. Experiments were also undertaken on the yeast dataset, which comprised 1.7% actual missing values, to test the hypothesis that CMVE performed better not only for randomly occurring but also for a real distribution of missing values. The results confirmed that CMVE consistently demonstrated superior and robust estimation capability of missing values compared with other methods for both series types of data, for the same order of computational complexity. A concise theoretical framework has also been formulated to validate the improved performance of the CMVE

Carbon Dioxide Compensation Values in Citronella and Lemongrass 1

Science.gov (United States)

Herath, H. M. Walter; Ormrod, Douglas P.

1977-01-01

Carbon dioxide compensation values of mature leaves from 10 selections of citronella (Cymbopogon nardus [L.] Rendle) grown at 32/27 or 27/21 C day/night temperatures and three strains of lemongrass (Cymbopogon citratus [D.C.] Stapf. and Cymbopogon flexuosus [D.C.] Stapf.) grown at 8- or 15-hour photoperiods were measured in a controlled environment at 25 C. All leaves had low compensation values but citronella varied from 1.3 to 9.7 μl/liter and lemongrass from 0.7 to 3.5 μl/liter. Lower growing temperature generally resulted in lower compensation values for citronella but there was no consistent photoperiod effect on lemongrass. PMID:16659935

Holistic oil field value management: using system dynamics for 'intermediate level' and 'value-based' modelling in the oil industry

International Nuclear Information System (INIS)

Corben, D.; Stevenson, R.; Wolstenholme, E.F.

1999-01-01

System dynamics has been seen primarily as a strategic tool, most effectively used at the highest level of strategy to identify robust policy interventions under a wide range of scenarios. However, an alternative, complementary and powerful role is emerging. This is at an 'intermediate level' in organisations to coordinate and integrate policies across the value chain. It is at this level where business value, as defined by the discounted value of future free cash flow, is both created and destroyed. This paper introduces the need for 'intermediate-level' and 'value-based' modelling and emphasises the natural role of system dynamics in supporting a methodology to fulfil the need. It describes the development of an approach and its application in the oil industry to coordinate the response of people and tools within operational, financial and commercial functions across the value chain to address a variety of problems and issues. (author)

A binomial random sum of present value models in investment analysis

OpenAIRE

Βουδούρη, Αγγελική; Ντζιαχρήστος, Ευάγγελος

1997-01-01

Stochastic present value models have been widely adopted in financial theory and practice and play a very important role in capital budgeting and profit planning. The purpose of this paper is to introduce a binomial random sum of stochastic present value models and offer an application in investment analysis.

Species Identification and Design Value Estimation of Wooden Members in Covered Bridges

Science.gov (United States)

Alex C. Wiedenhoeft; David E. Kretschmann

2014-01-01

Covered timber bridges are historic structures with unique aesthetic value. To preserve this value and maintain bridges in service, robust evaluation of their performance and safety is necessary. The strength of the timber found in covered bridges can vary considerably, not only because of age and condition, but also because of species and grade. For the practicing...

Entropy Evaluation Based on Value Validity

Directory of Open Access Journals (Sweden)

Tarald O. Kvålseth

2014-09-01

Full Text Available Besides its importance in statistical physics and information theory, the Boltzmann-Shannon entropy S has become one of the most widely used and misused summary measures of various attributes (characteristics in diverse fields of study. It has also been the subject of extensive and perhaps excessive generalizations. This paper introduces the concept and criteria for value validity as a means of determining if an entropy takes on values that reasonably reflect the attribute being measured and that permit different types of comparisons to be made for different probability distributions. While neither S nor its relative entropy equivalent S* meet the value-validity conditions, certain power functions of S and S* do to a considerable extent. No parametric generalization offers any advantage over S in this regard. A measure based on Euclidean distances between probability distributions is introduced as a potential entropy that does comply fully with the value-validity requirements and its statistical inference procedure is discussed.

INNOVATION AND THE VALUE OF FAILURE

OpenAIRE

William Townsend

2010-01-01

Innovation is a difficult phenomenon to evaluate. Innovation impacts the firm in a variety of ways. It is difficult to analyze the full impact of innovation because there is no single set of metrics that can capture its full significance. The metrics that have been traditionally used only capture a fraction of the true benefit derived by the firm. In addition, since the circumstances, values, structure and strategies vary greatly between industries and firms within industries, the efficacy of...

Employee-Organization Pro-environmental Values Fit and Pro-environmental Behavior: The Role of Supervisors' Personal Values.

Science.gov (United States)

Lu, Hui; Liu, Xia; Chen, Hong; Long, Ruyin

2017-12-18

This study examines the relationship among the employees-organization pro-environmental values fit (E-O PEVs fit), supervisors' PEVs and employees' pro-environmental behaviors (PEB). Informed by the PEB, organizational values and employee-organization fit literature, we propose and test hypotheses that under egoistic, altruistic and biosphere-value orientations, E-O PEVs fit versus non-fit have significant effects on employees' private-sphere PEB and public-sphere PEB, identifying supervisors' PEVs as a moderator. An empirical investigation indicates that the effect of E-O PEVs fit on employees' private-sphere PEB and public-sphere PEB varies as the value orientation differs. More specifically, under the context of altruistic and biosphere-value orientations, if the organizational PEVs do not match the employees' PEVs, especially when the former exceeds the latter, employees' PEB will rise as the organizational PEVs increase. As for egoistic value orientation, when organizational PEVs exceed employees' PEVs, not only will public-sphere PEB stop decreasing and tend to stabilize, but also private-sphere PEB will rise to a slight degree. Furthermore, compared with altruistic and biospheric values dimensions, supervisors who promote egoistic PEVs will have a more significant effect on the relationship between global E-O PEVs fit and employees' PEB. Finally, we suggest that the goals of an organization and its supervisors need to be combined within the actual situation of Chinese corporations to truly implement corporate green practices by balancing the profit goal and the environmental goal.

Time-varying Crash Risk

DEFF Research Database (Denmark)

Christoffersen, Peter; Feunoua, Bruno; Jeon, Yoontae

We estimate a continuous-time model with stochastic volatility and dynamic crash probability for the S&P 500 index and find that market illiquidity dominates other factors in explaining the stock market crash risk. While the crash probability is time-varying, its dynamic depends only weakly on re...

The value trade-off in higher education service: A qualitative intercultural approach to students’ perceptions

Directory of Open Access Journals (Sweden)

Danni Li

2016-08-01

Full Text Available Purpose: Higher Education Institutions have become a highly competitive market, where consumers (i.e. students are highly involved in their choices, and managers need to focus on competitive edges. This paper aims to understand the factors that influence student choice behaviour and fulfil student expectations of customer value in higher education institutions (HEIs. Design/methodology/approach: with qualitative information (focus groups collected from international students of several universities in Spain, Britain and China, the paper investigates the formation of customer value, as a trade-off between benefits and costs. This qualitative approach aims first at assessing this particular service through the concept of value through verifying both the positive and negative dimensions of HE, and second, to comment on the intercultural aspects of this dual approach to higher education consumption. Findings: the results show different levels of benefits: the functional value generally comes from infrastructures and good teachers that offer abundant practical experiences. The benefits from quality education also derived from teamwork with the colleagues who possess equal academic strength. Social benefits come from experiences outside the academic environment, working with people from different cultural backgrounds who have different perspectives. Emotional rewards come from University reputation and relationships with instructors. Costs of time and effort are differently seen across programs and vary widely upon nationalities and cultural backgrounds. Practical implications: since the competitive environments are fast becoming more and more complex added to the fact that it changes rapidly and dynamically, to concentrate on a few key elements are most important to the organizations survival. Different values of customers in different countries suggest that the strategy used by the corporation in a certain country, may not be apply to another

Time varying voltage combustion control and diagnostics sensor

Science.gov (United States)

Chorpening, Benjamin T [Morgantown, WV; Thornton, Jimmy D [Morgantown, WV; Huckaby, E David [Morgantown, WV; Fincham, William [Fairmont, WV

2011-04-19

A time-varying voltage is applied to an electrode, or a pair of electrodes, of a sensor installed in a fuel nozzle disposed adjacent the combustion zone of a continuous combustion system, such as of the gas turbine engine type. The time-varying voltage induces a time-varying current in the flame which is measured and used to determine flame capacitance using AC electrical circuit analysis. Flame capacitance is used to accurately determine the position of the flame from the sensor and the fuel/air ratio. The fuel and/or air flow rate (s) is/are then adjusted to provide reduced flame instability problems such as flashback, combustion dynamics and lean blowout, as well as reduced emissions. The time-varying voltage may be an alternating voltage and the time-varying current may be an alternating current.

"Just Give Me a Number!" Practical Values for the Social Discount Rate

Science.gov (United States)

Moore, Mark A.; Boardman, Anthony E.; Vining, Aidan R.; Weimer, David L.; Greenberg, David H.

2004-01-01

A major reason the quality of cost-benefit analysis (CBA) varies widely is inconsistent use of the social discount rate (SDR). This article offers guidance about the choice of the SDR. Namely, we recommend the following procedures: If the project is intragenerational (does not have effects beyond 50 years) and there is no crowding out of private…

Regional deposition of nasal sprays in adults: A wide ranging computational study.

Science.gov (United States)

Kiaee, Milad; Wachtel, Herbert; Noga, Michelle L; Martin, Andrew R; Finlay, Warren H

2018-05-01

The present work examines regional deposition within the nose for nasal sprays over a large and wide ranging parameter space by using numerical simulation. A set of 7 realistic adult nasal airway geometries was defined based on computed tomography images. Deposition in 6 regions of each nasal airway geometry (the vestibule, valve, anterior turbinate, posterior turbinate, olfactory, and nasopharynx) was determined for varying particle diameter, spray cone angle, spray release direction, particle injection speed, and particle injection location. Penetration of nasal spray particles through the airway geometries represented unintended lung exposure. Penetration was found to be relatively insensitive to injection velocity, but highly sensitive to particle size. Penetration remained at or above 30% for particles exceeding 10 μm in diameter for several airway geometries studied. Deposition in the turbinates, viewed as desirable for both local and systemic nasal drug delivery, was on average maximized for particles ranging from ~20 to 30 μm in diameter, and for low to zero injection velocity. Similar values of particle diameter and injection velocity were found to maximize deposition in the olfactory region, a potential target for nose-to-brain drug delivery. However, olfactory deposition was highly variable between airway geometries, with maximum olfactory deposition ranging over 2 orders of magnitude between geometries. This variability is an obstacle to overcome if consistent dosing between subjects is to be achieved for nose-to-brain drug delivery. Copyright © 2018 John Wiley & Sons, Ltd.

Detection of dynamically varying interaural time differences

DEFF Research Database (Denmark)

Kohlrausch, Armin; Le Goff, Nicolas; Breebaart, Jeroen

2010-01-01

of fringes surrounding the probe is equal to the addition of the effects of the individual fringes. In this contribution, we present behavioral data for the same experimental condition, called dynamically varying ITD detection, but for a wider range of probe and fringe durations. Probe durations varied...

Fault Detection for Non-Gaussian Stochastic Systems with Time-Varying Delay

Directory of Open Access Journals (Sweden)

Tao Li

2013-01-01

Full Text Available Fault detection (FD for non-Gaussian stochastic systems with time-varying delay is studied. The available information for the addressed problem is the input and the measured output probability density functions (PDFs of the system. In this framework, firstly, by constructing an augmented Lyapunov functional, which involves some slack variables and a tuning parameter, a delay-dependent condition for the existence of FD observer is derived in terms of linear matrix inequality (LMI and the fault can be detected through a threshold. Secondly, in order to improve the detection sensitivity performance, the optimal algorithm is applied to minimize the threshold value. Finally, paper-making process example is given to demonstrate the applicability of the proposed approach.

Central recirculation zone analysis in an unconfined tangential swirl burner with varying degrees of premixing

Energy Technology Data Exchange (ETDEWEB)

Valera-Medina, A. [CIATEQ, Parque Industrial Bernardo Quintana, Turbomachinery Department, Queretaro (Mexico); Syred, N.; Kay, P.; Griffiths, A. [Cardiff University, School of Engineering, Cardiff, Wales (United Kingdom)

2011-06-15

Swirl-stabilised combustion is one of the most widely used techniques for flame stabilisation, uses ranging from gas turbine combustors to pulverised coal-fired power stations. In gas turbines, lean premixed systems are of especial importance, giving the ability to produce low NOx systems coupled with wide stability limits. The common element is the swirl burner, which depends on the generation of an aerodynamically formed central recirculation zone (CRZ) and which serves to recycle heat and active chemical species to the root of the flame as well as providing low-velocity regions where the flame speed can match the local flow velocity. Enhanced mixing in and around the CRZ is another beneficial feature. The structure of the CRZ and hence that of the associated flames, stabilisation and mixing processes have shown to be extremely complex, three-dimensional and time dependent. The characteristics of the CRZ depend very strongly on the level of swirl (swirl number), burner configuration, type of flow expansion, Reynolds number (i.e. flowrate) and equivalence ratio. Although numerical methods have had some success when compared to experimental results, the models still have difficulties at medium to high swirl levels, with complex geometries and varied equivalence ratios. This study thus focuses on experimental results obtained to characterise the CRZ formed under varied combustion conditions with different geometries and some variation of swirl number in a generic swirl burner. CRZ behaviour has similarities to the equivalent isothermal state, but is strongly dependent on equivalence ratio, with interesting effects occurring with a high-velocity fuel injector. Partial premixing and combustion cause more substantive changes to the CRZ than pure diffusive combustion. (orig.)

Enhancing Established Counting Routines to Promote Place-Value Understanding: An Empirical Study in Early Elementary Classrooms

Science.gov (United States)

Fraivillig, Judith L.

2018-01-01

Understanding place value is a critical and foundational competency for elementary mathematics. Classroom teachers who endeavor to promote place-value development adopt a variety of established practices to varying degrees of effectiveness. In parallel, researchers have validated models of how young children acquire place-value understanding.…

Genome-wide Association Study of Personality Traits in the Long Life Family Study

Directory of Open Access Journals (Sweden)

Harold T Bae

2013-05-01

Full Text Available Personality traits have been shown to be associated with longevity and healthy aging. In order to discover novel genetic modifiers associated with personality traits as related with longevity, we performed a genome-wide association study (GWAS on personality factors assessed by NEO-FFI in individuals enrolled in the Long Life Family Study (LLFS, a study of 583 families (N up to 4595 with clustering for longevity in the United States and Denmark. Three SNPs, in almost perfect LD, associated with agreeableness reached genome-wide significance (p<10-8 and replicated in an additional sample of 1279 LLFS subjects, although one (rs9650241 failed to replicate and the other two were not available in two independent replication cohorts, the Baltimore Longitudinal Study of Aging and the New England Centenarian Study. Based on 10,000,000 permutations, the empirical p-value of 2X10-7 was observed for the genome-wide significant SNPs. Seventeen SNPs that reached marginal statistical significance in the two previous GWASs (p-value < 10-4 and 10-5, were also marginally significantly associated in this study (p-value < 0.05, although none of the associations passed the Bonferroni correction. In addition, we tested age-by-SNP interactions and found some significant associations. Since scores of personality traits in LLFS subjects change in the oldest ages, and genetic factors outweigh environmental factors to achieve extreme ages, these age-by-SNP interactions could be a proxy for complex gene-gene interactions affecting personality traits and longevity.

Corporate performance and the measures of value added

Directory of Open Access Journals (Sweden)

T. Petravičius

2008-09-01

Full Text Available In recent years, managers have turned their attention to the ways increasing the value of their companies. A number of competing measures have been developed and marketed by investment and consulting firms. This paper considers the ways in which value can be created or destroyed in a firm and looks at how to calculate the cost of capital used to measure the opportunity cost of investing funds in one particular business instead of others with equivalent risk. Next, we have a look at the four most widely used value enhancement measures including Economic Value Added, Cash Flow Return on Investment, Market Value Added, Cash Value Added and use an example to think of where these approaches yield similar results and where differences might occur. In conclusion, we summarize the new or unique points in these competing measures, establish the information they can give and explain how to use it when managing and creating shareholder value.

Tribological behavior and self-healing functionality of TiNbCN-Ag coatings in wide temperature range

Energy Technology Data Exchange (ETDEWEB)

Bondarev, A.V., E-mail: abondarev88@gmail.com; Kiryukhantsev-Korneev, Ph.V.; Levashov, E.A.; Shtansky, D.V., E-mail: shtansky@shs.misis.ru

2017-02-28

Highlights: • TiNbCN–Ag coatings for wide temperature range tribological applications. • Alloying with Nb and Ag improve tribological properties and oxidation resistance. • Ag-rich TiNbCN coatings show friction coefficient below 0.45 in range of 25–700 °C. • Ag-doped coatings show active oxidation protection and self-healing functionality. - Abstract: Ag- and Nb-doped TiCN coatings with about 2 at.% of Nb and Ag contents varied between 4.0 and 15.1 at.% were designed as promising materials for tribological applications in a wide temperature range. We report on the structure, mechanical, and tribological properties of TiNbCN-Ag coatings fabricated by simultaneous co-sputtering of TiC{sub 0.5} + 10%Nb{sub 2}C and Ag targets in comparison with those of Ag-free coating. The tribological characteristics were evaluated during constant-temperature tests both at room temperature and 300 °C, as well as during dynamic temperature ramp tests in the range of 25–700 °C. The coating structure and elemental composition were studied by means of X-ray diffraction, scanning and transmission electron microscopy, and glow discharge optical emission spectroscopy. The coating microstructures and elemental compositions inside wear tracks, as well as the wear products, were examined by scanning electron microscopy, energy-dispersive spectroscopy, and Raman spectroscopy. We demonstrate that simultaneous alloying with Nb and Ag permits to overcome the main drawbacks of TiCN coatings such as their relatively high values of friction coefficient at elevated temperatures and low oxidation resistance. It is shown that a relatively high amount of Ag (15 at.%) is required to provide enhanced tribological behavior in a wide temperature range of 25–700 °C. In addition, the prepared Ag-doped coatings demonstrated active oxidation protection and self-healing functionality due to the segregation of Ag metallic particles in damage areas such as cracks, pin-holes, or oxidation sites.

Limiting photocurrent analysis of a wide channel photoelectrochemical flow reactor

International Nuclear Information System (INIS)

Davis, Jonathan T; Esposito, Daniel V

2017-01-01

The development of efficient and scalable photoelectrochemical (PEC) reactors is of great importance for the eventual commercialization of solar fuels technology. In this study, we systematically explore the influence of convective mass transport and light intensity on the performance of a 3D-printed PEC flow cell reactor based on a wide channel, parallel plate geometry. Using this design, the limiting current density generated from the hydrogen evolution reaction at a p-Si metal–insulator–semiconductor (MIS) photocathode was investigated under varied reactant concentration, fluid velocity, and light intensity. Additionally, a simple model is introduced to predict the range of operating conditions (reactant concentration, light intensity, fluid velocity) for which the photocurrent generated in a parallel plate PEC flow cell is limited by light absorption or mass transport. This model can serve as a useful guide for the design and operation of wide-channel PEC flow reactors. The results of this study have important implications for PEC reactors operating in electrolytes with dilute reactant concentrations and/or under high light intensities where high fluid velocities are required in order to avoid operation in the mass transport-limited regime. (paper)

Ethnobotany, therapeutic value, phytochemistry and conservation status of Bowiea volubilis: A widely used bulbous plant in southern Africa.

Science.gov (United States)

Aremu, Adeyemi O; Moyo, Mack; Amoo, Stephen O; Van Staden, Johannes

2015-11-04

Bowiea volubilis Harv. ex Hook.f. (Family: Asparagaceae) is a bulbous medicinal plant widely used against numerous ailments including headache, muscular pains, infertility, cystitis and venereal diseases in southern Africa. To provide a critical and updated review of Bowiea volubilis with regards to its abundance, medicinal importance, conservation status and potential means to sustain its availability for future generations. A comprehensive literature search using online databases such as Web of Science, Google Scholar, Scopus and Springerlink as well as ethnobotanical literature was done in order to obtain, collate, synthesize and critically analyze available information on Bowiea volubilis. On the basis of its wide distribution in many Provinces in South Africa, Bowiea volubilis has a long history of applications among the different ethnic groups. These applications include its uses as purgatives and for the treatment or relief of microbial infections, skin disorders, pains and inflammation. Scientific validation of its diverse uses in traditional medicine has been demonstrated via antimicrobial, anti-inflammatory and toxicity assays. Available results indicate a general poor antimicrobial activity especially with the bulb extracts while the anti-inflammatory activity appears promising. Phytochemical screenings revealed that Bowiea volubilis contains cardiac glycosides and related compounds while reports of other classes of compounds are unavailable. In line with its usage in traditional medicine, the majority of available studies on the species have focused on the use of different solvent extracts from the bulbs. The destructive harvesting of bulbs has led to a continuous decimation of wild populations. Consequently, there are increasing conservational concerns on the sustainability of this species for continuous supply to meet escalating demands. Bowiea volubilis remains a widely used medicinal plant and available but limited scientific evidence indicates its

The Nation and the Family: The Impact of National Identification and Perceived Importance of Family Values on Homophobic Attitudes in Lithuania and Scotland.

Science.gov (United States)

Wakefield, Juliet R H; Kalinauskaite, Monika; Hopkins, Nick

The meanings attached to the nation can be consequential for group members' attitudes and beliefs. We examined how national identity definition can influence the extent of individuals' homophobia with 159 Lithuanian and 176 Scottish university students who completed a questionnaire which measured their national identification, homophobia, and the extent to which they felt traditional family values were central to their nation's identity. Consistent with nation-wide differences in the significance given to the family, Lithuanian participants perceived family values to be more important for their national identity and expressed higher levels of homophobia than did Scottish participants. Moreover, the relationship between level of national identification and homophobia was stronger in Lithuania than in Scotland. Analyses revealed that the perceived importance of family values helped explain the difference between homophobia levels in Lithuania and Scotland. In both sites we found an indirect effect of national identification on homophobia via the perceived importance of family values, but this effect was significantly stronger for Lithuanian participants. These findings illustrate the ways in which identification with the nation is relevant to attitudes concerning sexuality, and how this varies according to national context. Our work indicates that LGBT rights campaigns should be informed by the knowledge that homophobia may be perpetuated by national valorisation of the family.

A solution to the varying response of the linear power monitor induced by xenon poisoning

Energy Technology Data Exchange (ETDEWEB)

Godsey, T A; Randall, J D [Texas A and M University (United States)

1974-07-01

After conversion to FLIP fuel at Texas A and M, the fuel temperatures were examined very carefully. It was observed that the fuel temperature at 1 Mw varied over a wide range during the week. This variation was shown to be due to the variation in response of the linear CIC which was used to establish reactor power level. A modification of the linear power monitor was designed and installed. The response of this system was verified by using cobalt wires, fuel temperature, and a fission chamber located at 6 feet from the reactor core. The system has proven to be operationally satisfactory. (author)

Targeting 160 candidate genes for blood pressure regulation with a genome-wide genotyping array.

Directory of Open Access Journals (Sweden)

Siim Sõber

2009-06-01

Full Text Available The outcome of Genome-Wide Association Studies (GWAS has challenged the field of blood pressure (BP genetics as previous candidate genes have not been among the top loci in these scans. We used Affymetrix 500K genotyping data of KORA S3 cohort (n = 1,644; Southern-Germany to address (i SNP coverage in 160 BP candidate genes; (ii the evidence for associations with BP traits in genome-wide and replication data, and haplotype analysis. In total, 160 gene regions (genic region+/-10 kb covered 2,411 SNPs across 11.4 Mb. Marker densities in genes varied from 0 (n = 11 to 0.6 SNPs/kb. On average 52.5% of the HAPMAP SNPs per gene were captured. No evidence for association with BP was obtained for 1,449 tested SNPs. Considerable associations (P50% of HAPMAP SNPs were tagged. In general, genes with higher marker density (>0.2 SNPs/kb revealed a better chance to reach close to significance associations. Although, none of the detected P-values remained significant after Bonferroni correction (P<0.05/2319, P<2.15 x 10(-5, the strength of some detected associations was close to this level: rs10889553 (LEPR and systolic BP (SBP (P = 4.5 x 10(-5 as well as rs10954174 (LEP and diastolic BP (DBP (P = 5.20 x 10(-5. In total, 12 markers in 7 genes (ADRA2A, LEP, LEPR, PTGER3, SLC2A1, SLC4A2, SLC8A1 revealed considerable association (P<10(-3 either with SBP, DBP, and/or hypertension (HYP. None of these were confirmed in replication samples (KORA S4, HYPEST, BRIGHT. However, supportive evidence for the association of rs10889553 (LEPR and rs11195419 (ADRA2A with BP was obtained in meta-analysis across samples stratified either by body mass index, smoking or alcohol consumption. Haplotype analysis highlighted LEPR and PTGER3. In conclusion, the lack of associations in BP candidate genes may be attributed to inadequate marker coverage on the genome-wide arrays, small phenotypic effects of the loci and/or complex interaction with life-style and metabolic parameters.

Improving University Research Value

Directory of Open Access Journals (Sweden)

Kelley O’Reilly

2012-07-01

Full Text Available This article investigates the current data management practices of university researchers at an Intermountain West land-grant research university in the United States. Key findings suggest that researchers are primarily focused on the collection and housing of research data. However, additional research value exists within the other life cycle stages for research data—specifically in the stages of delivery and maintenance. These stages are where most new demands and requirements exist for data management plans and policies that are conditional for external grant funding; therefore, these findings expose a “gap” in current research practice. These findings should be of interest to academics and practitioners alike as findings highlight key management gaps in the life cycle of research data. This study also suggests a course of action for academic institutions to coalesce campus-wide assets to assist researchers in improving research value.

Time-Varying Distortions of Binaural Information by Bilateral Hearing Aids

Science.gov (United States)

Rodriguez, Francisco A.; Portnuff, Cory D. F.; Goupell, Matthew J.; Tollin, Daniel J.

2016-01-01

In patients with bilateral hearing loss, the use of two hearing aids (HAs) offers the potential to restore the benefits of binaural hearing, including sound source localization and segregation. However, existing evidence suggests that bilateral HA users’ access to binaural information, namely interaural time and level differences (ITDs and ILDs), can be compromised by device processing. Our objective was to characterize the nature and magnitude of binaural distortions caused by modern digital behind-the-ear HAs using a variety of stimuli and HA program settings. Of particular interest was a common frequency-lowering algorithm known as nonlinear frequency compression, which has not previously been assessed for its effects on binaural information. A binaural beamforming algorithm was also assessed. Wide dynamic range compression was enabled in all programs. HAs were placed on a binaural manikin, and stimuli were presented from an arc of loudspeakers inside an anechoic chamber. Stimuli were broadband noise bursts, 10-Hz sinusoidally amplitude-modulated noise bursts, or consonant–vowel–consonant speech tokens. Binaural information was analyzed in terms of ITDs, ILDs, and interaural coherence, both for whole stimuli and in a time-varying sense (i.e., within a running temporal window) across four different frequency bands (1, 2, 4, and 6 kHz). Key findings were: (a) Nonlinear frequency compression caused distortions of high-frequency envelope ITDs and significantly reduced interaural coherence. (b) For modulated stimuli, all programs caused time-varying distortion of ILDs. (c) HAs altered the relationship between ITDs and ILDs, introducing large ITD–ILD conflicts in some cases. Potential perceptual consequences of measured distortions are discussed. PMID:27698258

The economic value of an investment in physiotherapy education: a net present value analysis.

Science.gov (United States)

Rivers, George; Foo, Jonathan; Ilic, Dragan; Nicklen, Peter; Reeves, Scott; Walsh, Kieran; Maloney, Stephen

2015-07-01

What is the economic value for an individual to invest in physiotherapy undergraduate education in Australia? How is this affected by increased education costs or decreased wages? A cost-benefit analysis using a net present value (NPV) approach was conducted and reported in Australian dollars. In relation to physiotherapy education, the NPV represents future earnings as a physiotherapist minus the direct and indirect costs in obtaining the degree. Sensitivity analyses were conducted to consider varying levels of experience, public versus private sector, and domestic versus international student fees. Comparable calculations were made for educational investments in medicine and nursing/midwifery. Assuming an expected discount rate of 9.675%, investment in education by domestic students with approximately 34 years of average work experience yields a NPV estimated at $784,000 for public sector physiotherapists and $815,000 for private sector therapists. In relation to international students, the NPV results for an investment and career as a physiotherapist is estimated at $705,000 in the public sector and $736,000 in the private sector. With an approximate payback period of 4 years, coupled with strong and positive NPV values, physiotherapy education in Australia is a financially attractive prospect and a viable value proposition for those considering a career in this field. Copyright © 2015 Australian Physiotherapy Association. Published by Elsevier B.V. All rights reserved.

New varying speed of light theories

CERN Document Server

Magueijo, J

2003-01-01

We review recent work on the possibility of a varying speed of light (VSL). We start by discussing the physical meaning of a varying $c$, dispelling the myth that the constancy of $c$ is a matter of logical consistency. We then summarize the main VSL mechanisms proposed so far: hard breaking of Lorentz invariance; bimetric theories (where the speeds of gravity and light are not the same); locally Lorentz invariant VSL theories; theories exhibiting a color dependent speed of light; varying $c$ induced by extra dimensions (e.g. in the brane-world scenario); and field theories where VSL results from vacuum polarization or CPT violation. We show how VSL scenarios may solve the cosmological problems usually tackled by inflation, and also how they may produce a scale-invariant spectrum of Gaussian fluctuations, capable of explaining the WMAP data. We then review the connection between VSL and theories of quantum gravity, showing how ``doubly special'' relativity has emerged as a VSL effective model of quantum space...

The Economic Value of Changes in Water Quality

DEFF Research Database (Denmark)

Jensen, Anne Kejser

Water quality is from both a European and Danish perspective challenged by private use of the resource. The public good characteristics of the resource require that regulation should internalize the non-market values of water quality, in order to reach an optimal level from a welfare economic...... perspective. Valuation using stated preference techniques to value changes in ecosystem services has been widely used to estimate values of water quality. However, heterogeneity in values exists across different groups in the population. The objective of this PhD-thesis is to explore two different kinds...... of preference heterogeneity, when valuing changes in water quality. The PhD thesis consists of four papers all related to heterogeneity in the public preferences for water quality improvements. Papers referred to as 1, 2 and 3 are based on a discrete choice experiment (DCE) on water quality improvements...

Methods to estimate breeding values in honey bees

NARCIS (Netherlands)

Brascamp, E.W.; Bijma, P.

2014-01-01

Background Efficient methodologies based on animal models are widely used to estimate breeding values in farm animals. These methods are not applicable in honey bees because of their mode of reproduction. Observations are recorded on colonies, which consist of a single queen and thousands of workers

Thick melanoma: prognostic value of positive sentinel nodes

NARCIS (Netherlands)

Vermeeren, Lenka; van der Ent, Fred W. C.; Sastrowijoto, Prapto S. H.; Hulsewé, Karel W. E.

2009-01-01

BACKGROUND: Sentinel lymph node biopsy (SNB) is a widely accepted procedure used to accurately stage patients with melanoma. Its value in patients with thick melanoma (Breslow thickness >4 mm) is reason for discussion because of the generally poor prognosis of these patients. The purpose of this

Neural representation of expected value in the adolescent brain.

Science.gov (United States)

Barkley-Levenson, Emily; Galván, Adriana

2014-01-28

Previous work shows that the adolescent reward system is hyperactive, but this finding may be confounded by differences in how teens value money. To address this, we examined the neural ontogeny of objective value representation. Adolescent and adult participants performed a monetary gambling task in which they chose to accept or reject gambles of varying expected value. Increasing expected value had a stronger influence over gambling choices in adolescents relative to adults, an effect that was paralleled by greater activation in the ventral striatum in adolescents. This unique adolescent ventral striatum response remained even after matching groups on acceptance behavior. These behavioral and neural data suggest that the value of available options has a greater influence in adolescent versus adult choices, even when objective value and subjective choice are held constant. This research provides further evidence that hyperactivation of reward circuitry in adolescence may be a normative ontogenetic shift that is due to greater valuation in the adolescent brain.

Complexity Variability Assessment of Nonlinear Time-Varying Cardiovascular Control

Science.gov (United States)

Valenza, Gaetano; Citi, Luca; Garcia, Ronald G.; Taylor, Jessica Noggle; Toschi, Nicola; Barbieri, Riccardo

2017-02-01

The application of complex systems theory to physiology and medicine has provided meaningful information about the nonlinear aspects underlying the dynamics of a wide range of biological processes and their disease-related aberrations. However, no studies have investigated whether meaningful information can be extracted by quantifying second-order moments of time-varying cardiovascular complexity. To this extent, we introduce a novel mathematical framework termed complexity variability, in which the variance of instantaneous Lyapunov spectra estimated over time serves as a reference quantifier. We apply the proposed methodology to four exemplary studies involving disorders which stem from cardiology, neurology and psychiatry: Congestive Heart Failure (CHF), Major Depression Disorder (MDD), Parkinson’s Disease (PD), and Post-Traumatic Stress Disorder (PTSD) patients with insomnia under a yoga training regime. We show that complexity assessments derived from simple time-averaging are not able to discern pathology-related changes in autonomic control, and we demonstrate that between-group differences in measures of complexity variability are consistent across pathologies. Pathological states such as CHF, MDD, and PD are associated with an increased complexity variability when compared to healthy controls, whereas wellbeing derived from yoga in PTSD is associated with lower time-variance of complexity.

Initial locomotor sensitivity to cocaine varies widely among inbred mouse strains.

Science.gov (United States)

Wiltshire, T; Ervin, R B; Duan, H; Bogue, M A; Zamboni, W C; Cook, S; Chung, W; Zou, F; Tarantino, L M

2015-03-01

Initial sensitivity to psychostimulants can predict subsequent use and abuse in humans. Acute locomotor activation in response to psychostimulants is commonly used as an animal model of initial drug sensitivity and has been shown to have a substantial genetic component. Identifying the specific genetic differences that lead to phenotypic differences in initial drug sensitivity can advance our understanding of the processes that lead to addiction. Phenotyping inbred mouse strain panels are frequently used as a first step for studying the genetic architecture of complex traits. We assessed locomotor activation following a single, acute 20 mg/kg dose of cocaine (COC) in males from 45 inbred mouse strains and observed significant phenotypic variation across strains indicating a substantial genetic component. We also measured levels of COC, the active metabolite, norcocaine and the major inactive metabolite, benzoylecgonine, in plasma and brain in the same set of inbred strains. Pharmacokinetic (PK) and behavioral data were significantly correlated, but at a level that indicates that PK alone does not account for the behavioral differences observed across strains. Phenotypic data from this reference population of inbred strains can be utilized in studies aimed at examining the role of psychostimulant-induced locomotor activation on drug reward and reinforcement and to test theories about addiction processes. Moreover, these data serve as a starting point for identifying genes that alter sensitivity to the locomotor stimulatory effects of COC. © 2015 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Many Options in New Orleans Choice System: School Characteristics Vary Widely

Science.gov (United States)

Arce-­Trigatti, Paula; Harris, Douglas N.; Jabbar, Huriya; Lincove, Jane Arnold

2015-01-01

Previous studies have focused on the differences between charter schools and district schools, treating all charters within a community as essentially alike. In effect, these studies take a "top­-down" approach, assuming that the governance of the school (charter versus district) determines the nature of the school. This approach may be…

Wide-band CMOS low-noise amplifier exploiting thermal noise canceling

OpenAIRE

Bruccoleri, F.; Klumperink, Eric A.M.; Nauta, Bram

2004-01-01

Known elementary wide-band amplifiers suffer from a fundamental tradeoff between noise figure (NF) and source impedance matching, which limits the NF to values typically above 3 dB. Global negative feedback can be used to break this tradeoff, however, at the price of potential instability. In contrast, this paper presents a feedforward noise-canceling technique, which allows for simultaneous noise and impedance matching, while canceling the noise and distortion contributions of the matching d...

Spatially varying selection shapes life history clines among populations of Drosophila melanogaster from sub-Saharan Africa.

Science.gov (United States)

Fabian, D K; Lack, J B; Mathur, V; Schlötterer, C; Schmidt, P S; Pool, J E; Flatt, T

2015-04-01

Clines in life history traits, presumably driven by spatially varying selection, are widespread. Major latitudinal clines have been observed, for example, in Drosophila melanogaster, an ancestrally tropical insect from Africa that has colonized temperate habitats on multiple continents. Yet, how geographic factors other than latitude, such as altitude or longitude, affect life history in this species remains poorly understood. Moreover, most previous work has been performed on derived European, American and Australian populations, but whether life history also varies predictably with geography in the ancestral Afro-tropical range has not been investigated systematically. Here, we have examined life history variation among populations of D. melanogaster from sub-Saharan Africa. Viability and reproductive diapause did not vary with geography, but body size increased with altitude, latitude and longitude. Early fecundity covaried positively with altitude and latitude, whereas lifespan showed the opposite trend. Examination of genetic variance-covariance matrices revealed geographic differentiation also in trade-off structure, and QST -FST analysis showed that life history differentiation among populations is likely shaped by selection. Together, our results suggest that geographic and/or climatic factors drive adaptive phenotypic differentiation among ancestral African populations and confirm the widely held notion that latitude and altitude represent parallel gradients. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Molecular weight profiles of proanthocyanidin polymers

Science.gov (United States)

Vincent M. Williams; Lawrence J. Porter; Richard W. Hemingway

1983-01-01

The MW profiles of proanthocyanidin polymers (condensed tannins) from 32 samples representing a wide range of plant tissues of many different species have been obtained by gel permeation chromatography of the peracetate derivatives. The tannins vary widely in MW, with M values for the peracetates in the range 1600-5500. The MW profiles vary greatly from those with...

Lessons Learned from A System-Wide Evidence-Based Practice Program Implementation

Science.gov (United States)

2017-04-25

incorporating scientific evidence, clinical expertise and the patient’s values and preferences to provide quality healthcare . Despite growing...MEMORANDUM FOR ST DEPARTMENT OF THE AIR FORCE 59TH MEDICAL WING (AETC) JOINT BASE SAN ANTONIO - LACKLAND TEXAS ATTN: LT COL JACQUELINE KILLIAN...FROM: 59 MDW/SGVU SUBJECT: Professional Presentation Approval 14 FEB 2017 1. Your paper, entitled Lesson Learned From A System-Wide Evidence- Based

New values of time and reliability in passenger transport in the Netherlands

NARCIS (Netherlands)

Kouwenhoven, M.; de Jong, G.; Koster, P.R.; van den Berg, V.A.C.; Verhoef, E.T.; Bates, J.; Warffemius, P.

2014-01-01

We have established new values of time (VOTs) and values of travel time reliability (VORs) for use in cost-benefit analysis (CBA) of transport projects in The Netherlands. This was the first national study in The Netherlands (and one of the first world-wide) to investigate these topics empirically

A Generalized Framework for Non-Stationary Extreme Value Analysis

Science.gov (United States)

Ragno, E.; Cheng, L.; Sadegh, M.; AghaKouchak, A.

2017-12-01

Empirical trends in climate variables including precipitation, temperature, snow-water equivalent at regional to continental scales are evidence of changes in climate over time. The evolving climate conditions and human activity-related factors such as urbanization and population growth can exert further changes in weather and climate extremes. As a result, the scientific community faces an increasing demand for updated appraisal of the time-varying climate extremes. The purpose of this study is to offer a robust and flexible statistical tool for non-stationary extreme value analysis which can better characterize the severity and likelihood of extreme climatic variables. This is critical to ensure a more resilient environment in a changing climate. Following the positive feedback on the first version of Non-Stationary Extreme Value Analysis (NEVA) Toolbox by Cheng at al. 2014, we present an improved version, i.e. NEVA2.0. The upgraded version herein builds upon a newly-developed hybrid evolution Markov Chain Monte Carlo (MCMC) approach for numerical parameters estimation and uncertainty assessment. This addition leads to a more robust uncertainty estimates of return levels, return periods, and risks of climatic extremes under both stationary and non-stationary assumptions. Moreover, NEVA2.0 is flexible in incorporating any user-specified covariate other than the default time-covariate (e.g., CO2 emissions, large scale climatic oscillation patterns). The new feature will allow users to examine non-stationarity of extremes induced by physical conditions that underlie the extreme events (e.g. antecedent soil moisture deficit, large-scale climatic teleconnections, urbanization). In addition, the new version offers an option to generate stationary and/or non-stationary rainfall Intensity - Duration - Frequency (IDF) curves that are widely used for risk assessment and infrastructure design. Finally, a Graphical User Interface (GUI) of the package is provided, making NEVA

The value of windpower: An investigation using a qualified production cost model

International Nuclear Information System (INIS)

Milligan, M.R.; Miller, A.H.

1993-07-01

As part of the US Department of Energy's Wind Energy Program at the National Renewable Energy Laboratory, we are using the Environmental Defense Fund's Electric Utility Financial ampersand Production Cost Model (Elfin) as a tool to determine the value of wind energy to specific utilities. The cases we have developed exercise a number of options in the way in which wind energy is treated: (1) as a load modifer (negative load); (2) as a quick-start supply-side resource with hourly varying output; and (3) probabilistically, using time-varying Weibull distributions. By using two wind speed distributions, two different wind turbines, and two different utilities, we show what the wind turbine cost/kW might be that results in a positive value of wind energy for these utilities

Derivation of the extrinsic values of biological diversity from its intrinsic value and of both from the first principles of evolution.

Science.gov (United States)

White, Peter S

2013-12-01

Conservation ethics have been based on 2 philosophical value systems: extrinsic value (defined broadly to include all values that derive from something external to the thing valued) and intrinsic value. Valuing biological diversity on the basis of an extrinsic value system is problematic because measurement is often difficult; extrinsic value changes as spatial or temporal scales change; extrinsic value differs on the basis of external factors; some species have trivial or negative extrinsic values; and extrinsic value varies across human cultures and societies and with such factors as socioeconomic conditions, individual experiences, and educational backgrounds. Valuing biological diversity on the basis of an intrinsic value system also poses challenges because intrinsic value can be seen as a disguised form of human extrinsic value; intrinsic value is initially ambiguous as to which objects or characteristics of biological diversity are to being valued; all aspects of biological diversity (e.g., species and ecosystems) are transitory; species and ecosystems are not static concrete entities; and intrinsic value of one species is often in conflict with the intrinsic value of other species. Extrinsic and intrinsic value systems share a common origin, such that extrinsic values are always derived from intrinsic value and life mutely expresses both intrinsic and extrinsic values-these are derived from and are products of biological evolution. Probing the values that underlie conservation helps the community clearly articulate its aims. Derivación de los Valores Extrínsecos de la Biodiversidad a Partir de sus Valores Intrínsecos y de Ambos a Partir de los Primeros Principios de la Evolución. © 2013 Society for Conservation Biology.

The Role of School Principals in Shaping Children's Values.

Science.gov (United States)

Berson, Yair; Oreg, Shaul

2016-12-01

Instilling values in children is among the cornerstones of every society. There is wide agreement that beyond academic teaching, schools play an important role in shaping schoolchildren's character, imparting in them values such as curiosity, achievement, benevolence, and citizenship. Despite the importance of this topic, we know very little about whether and how schools affect children's values. In this large-scale longitudinal study, we examined school principals' roles in the development of children's values. We hypothesized that relationships exist between principals' values and changes in children's values through the mediating effect of the school climate. To test our predictions, we collected data from 252 school principals, 3,658 teachers, and 49,401 schoolchildren. A multilevel structural-equation-modeling analysis yielded overall support for our hypotheses. These findings contribute to understanding the development of children's values and the far-reaching impact of leaders' values. They also demonstrate effects of schools on children beyond those on academic achievement.

Hematocrit and plasma osmolality values of young-of-year shortnose sturgeon following acute exposures to combinations of salinity and temperature

Science.gov (United States)

Ziegeweid, J.R.; Black, M.C.

2010-01-01

Little is known about the physiological capabilities of young-of-year (YOY) shortnose sturgeon. In this study, plasma osmolality and hematocrit values were measured for YOY shortnose sturgeon following 48-h exposures to 12 different combinations of salinity and temperature. Hematocrit levels varied significantly with temperature and age, and plasma osmolalities varied significantly with salinity and age. Plasma osmolality and hematocrit values were similar to previously published values for other sturgeons of similar age and size in similar treatment conditions. ?? 2010 Springer Science+Business Media B.V.

Varying the number of bidders in the first-price sealed-bid auction: experimental evidence for the one-shot game

NARCIS (Netherlands)

Füllbrunn, S.C.; Neugebauer, T.

2013-01-01

The paper reports experimental data on the behavior in the first-price sealed-bid auction for a varying number of bidders when values and bids are private information. This feedback-free design is proposed for the experimental test of the one-shot game situation. We consider both within-subjects and

A global method for calculating plant CSR ecological strategies applied across biomes world-wide

NARCIS (Netherlands)

Pierce, S.; Negreiros, D.; Cerabolini, B.E.L.; Kattge, J.; Díaz, S.; Kleyer, M.; Shipley, B.; Wright, S.J.; Soudzilovskaia, N.A.; Onipchenko, V.G.; van Bodegom, P.M.; Frenette-Dussault, C.; Weiher, E.; Pinho, B.X.; Cornelissen, J.H.C.; Grime, J.P.; Thompson, K.; Hunt, R.; Wilson, P.J.; Buffa, G.; Nyakunga, O.C.; Reich, P.B.; Caccianiga, M.; Mangili, F.; Ceriani, R.M.; Luzzaro, A.; Brusa, G.; Siefert, A.; Barbosa, N.P.U.; Chapin III, F.S.; Cornwell, W.K.; Fang, Jingyun; Wilson Fernandez, G.; Garnier, E.; Le Stradic, S.; Peñuelas, J.; Melo, F.P.L.; Slaviero, A.; Tabarrelli, M.; Tampucci, D.

2017-01-01

Competitor, stress-tolerator, ruderal (CSR) theory is a prominent plant functional strategy scheme previously applied to local floras. Globally, the wide geographic and phylogenetic coverage of available values of leaf area (LA), leaf dry matter content (LDMC) and specific leaf area (SLA)

Varying constants, black holes, and quantum gravity

International Nuclear Information System (INIS)

Carlip, S.

2003-01-01

Tentative observations and theoretical considerations have recently led to renewed interest in models of fundamental physics in which certain 'constants' vary in time. Assuming fixed black hole mass and the standard form of the Bekenstein-Hawking entropy, Davies, Davis and Lineweaver have argued that the laws of black hole thermodynamics disfavor models in which the fundamental electric charge e changes. I show that with these assumptions, similar considerations severely constrain 'varying speed of light' models, unless we are prepared to abandon cherished assumptions about quantum gravity. Relaxation of these assumptions permits sensible theories of quantum gravity with ''varying constants,'' but also eliminates the thermodynamic constraints, though the black hole mass spectrum may still provide some restrictions on the range of allowable models

Master-slave exponential synchronization of delayed complex-valued memristor-based neural networks via impulsive control.

Science.gov (United States)

Li, Xiaofan; Fang, Jian-An; Li, Huiyuan

2017-09-01

This paper investigates master-slave exponential synchronization for a class of complex-valued memristor-based neural networks with time-varying delays via discontinuous impulsive control. Firstly, the master and slave complex-valued memristor-based neural networks with time-varying delays are translated to two real-valued memristor-based neural networks. Secondly, an impulsive control law is constructed and utilized to guarantee master-slave exponential synchronization of the neural networks. Thirdly, the master-slave synchronization problems are transformed into the stability problems of the master-slave error system. By employing linear matrix inequality (LMI) technique and constructing an appropriate Lyapunov-Krasovskii functional, some sufficient synchronization criteria are derived. Finally, a numerical simulation is provided to illustrate the effectiveness of the obtained theoretical results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Precision phase estimation based on weak-value amplification

Science.gov (United States)

Qiu, Xiaodong; Xie, Linguo; Liu, Xiong; Luo, Lan; Li, Zhaoxue; Zhang, Zhiyou; Du, Jinglei

2017-02-01

In this letter, we propose a precision method for phase estimation based on the weak-value amplification (WVA) technique using a monochromatic light source. The anomalous WVA significantly suppresses the technical noise with respect to the intensity difference signal induced by the phase delay when the post-selection procedure comes into play. The phase measured precision of this method is proportional to the weak-value of a polarization operator in the experimental range. Our results compete well with the wide spectrum light phase weak measurements and outperform the standard homodyne phase detection technique.

A national survey of genetic counselors' personal values.

Science.gov (United States)

Pirzadeh, Sara M; McCarthy Veach, Patricia; Bartels, Dianne M; Kao, Juihsien; Leroy, Bonnie S

2007-12-01

Personal values are motivational sources for an individual's actions [Hitlin and Piliavin (Annual Review of Sociology 30:359-393, 2004)]. Genetic counselors' values may influence their behaviors in clinical practice, but a profile of their personal values has not been identified empirically. In this study, 292 genetic counselors completed the Schwartz Universal Values Questionnaire (SUVQ; Schwartz, S. H. (1992). Universals in the content and structure of values: Theoretical advances and empirical tests in 20 countries. In M. Zanna (Ed.), Advances in experimental social psychology (pp. 1-65). Boston, MA: Academic.), a widely used measure of value types, and provided information about their demographic characteristics. Results indicate that respondents highly valued benevolence, self-direction, achievement, and universalism indicating a strong pattern of concern for the welfare of others. They placed considerably less value on stimulation, tradition, and power, which reflect personal interests. Respondents who reported practicing a religion scored significantly lower on stimulation and hedonism and higher on tradition and spirituality than those not practicing; married respondents and parents scored significantly lower on stimulation and achievement; and males scored higher on power than females. The value types are described, and training and research recommendations are provided.

Balancing tradeoffs: Reconciling multiple environmental goals when ecosystem services vary regionally

Science.gov (United States)

O’Connell, Christine S.; Carlson, Kimberly M.; Cuadra, Santiago; Feeley, Kenneth J.; Gerber, James; West, Paul C.; Polasky, Stephen

2018-06-01

As the planet’s dominant land use, agriculture often competes with the preservation of natural systems that provide globally and regionally important ecosystem services. How agriculture impacts ecosystem service delivery varies regionally, among services being considered, and across spatial scales. Here, we assess the tradeoffs between four ecosystem services—agricultural production, carbon storage, biophysical climate regulation, and biodiversity—using as a case study the Amazon, an active frontier of agricultural expansion. We find that the highest values for each of the ecosystem services are concentrated in different regions. Agricultural production potential and carbon storage are highest in the north and west, biodiversity greatest in the west, and climate regulation services most vulnerable to disruption in the south and east. Using a simple optimization model, we find that under scenarios of agricultural expansion that optimize total production across ecosystem services, small increases in priority for one ecosystem service can lead to reductions in other services by as much as 140%. Our results highlight the difficulty of managing landscapes for multiple environmental goals; the approach presented here can be adapted to guide value-laden conservation decisions and identify potential solutions that balance priorities.

Use of an amorphous silicon EPID for measuring MLC calibration at varying gantry angle

International Nuclear Information System (INIS)

Clarke, M F; Budgell, G J

2008-01-01

Amorphous silicon electronic portal imaging devices (EPIDs) are used to perform routine quality control (QC) checks on the multileaf collimators (MLCs) at this centre. Presently, these checks are performed at gantry angle 0 0 and are considered to be valid for all other angles. Since therapeutic procedures regularly require the delivery of MLC-defined fields to the patient at a wide range of gantry angles, the accuracy of the QC checks at other gantry angles has been investigated. When the gantry is rotated to angles other than 0 0 it was found that the apparent pixel size measured using the EPID varies up to a maximum value of 0.0015 mm per pixel due to a sag in the EPID of up to 9.2 mm. A correction factor was determined using two independent methods at a range of gantry angles between 0 deg. and 360 deg. The EPID was used to measure field sizes (defined by both x-jaws and MLC) at a range of gantry angles and, after this correction had been applied, any residual gravitational sag was studied. It was found that, when fields are defined by the x-jaws and y-back-up jaws, no errors of greater than 0.5 mm were measured and that these errors were no worse when the MLC was used. It was therefore concluded that, provided the correction is applied, measurements of the field size are, in practical terms, unaffected by gantry angle. Experiments were also performed to study how the reproducibility of individual leaves is affected by gantry angle. Measurements of the relative position of each individual leaf (minor offsets) were performed at a range of gantry angles and repeated three times. The position reproducibility was defined by the RMS error in the position of each leaf and this was found to be 0.24 mm and 0.21 mm for the two leaf banks at a gantry angle of 0 0 . When measurements were performed at a range of gantry angles, these reproducibility values remained within 0.09 mm and 0.11 mm. It was therefore concluded that the calibration of the Elekta MLC is stable at

A set-valued approach to FDI an FTC of wind turbines

DEFF Research Database (Denmark)

Casau, Pedro; Rosa, Paulo; Tabatabaeipour, Mojtaba

2015-01-01

A complete methodology to design robust Fault Detection and Isolation (FDI) filters and Fault Tolerant Control (FTC) schemes for Linear Parameter Varying (LPV) systems is proposed, with particular focus on its applicability to wind turbines. The paper takes advantage of the recent advances in model...... falsification using Set-Valued Observers (SVOs) that led to the development of FDI methods for uncertain linear time-varying systems, with promising results in terms of the time required to diagnose faults. An integration of such SVO-based FDI methods with robust control synthesis is described, in order...

A topological approach to migration and visualization of time-varying volume data

International Nuclear Information System (INIS)

Fujishiro, Issei; Otsuka, Rieko; Hamaoka, Aya; Takeshima, Yuriko; Takahashi, Shigeo

2004-01-01

Rapid advance in high performance computing and measurement technologies has recently made it possible to produce a stupendous amount of time-varying volume datasets in various disciplines. However, there exist a few known visual exploration tools which allow us to investigate the core of their complex behavior effectively. In this article, our previous approach to topological volume skeletonization is extended to capture the topological skeleton of a 4D volumetric field in terms of critical timing. A cyclic information drilldown scheme, termed T-map, is presented, where a wide choice of information visualization techniques are deployed so that the users are allowed to repeatedly squeeze partial spatiotemporal domains of interest until the size gets fitted into an available computing storage space, prior to topologically-accentuated visualization of the pinpointed volumetric domains. A case study with datasets from atomic collision research is performed to illustrate the feasibility of the present method. (author)

Marijuana smoking: effects of varying puff volume and breathhold duration.

Science.gov (United States)

Azorlosa, J L; Greenwald, M K; Stitzer, M L

1995-02-01

Two studies were conducted to quantify biological and behavioral effects resulting from exposure to controlled doses of marijuana smoke. In one study, puff volume (30, 60 and 90 ml) and in a second study, breathhold duration (0, 10 and 20 sec) were systematically varied while holding constant other smoking topography parameters (number of puffs = 10, interpuff interval = 60 sec and inhalation volume = 25% of vital capacity). Each study also varied levels of delta 9-tetrahydro-cannabinol marijuana cigarette content (1.75% and 3.55%). Regular marijuana users served as subjects (n = 7 in each experiment). Subjects smoked 10 puffs in each of six sessions; a seventh, nonsmoking session (all measures recorded at the same times as in active smoking sessions) served as a control. Variations in puff volume produced significant dose-related changes in postsmoking plasma delta 9-tetrahydro-cannabinol levels, carbon monoxide boost and subjective effects (e.g., "high"). In contrast, breathholding for 10 or 20 sec versus 0 sec increased plasma delta 9-tetrahydro-cannabinol levels but not CO boost or subjective effects. Task performance measures were not reliably influenced by marijuana smoke exposure within the dosing ranges examined. These findings confirm the utility of the controlled smoking technology, support the notion that cumulative puff volume systematically influences biological exposure and subjective effects, but cast doubt on the common belief that prolonged breathholding of marijuana smoke enhances classical subjective effects associated with its reinforcing value in humans.

Error Analysis for RADAR Neighbor Matching Localization in Linear Logarithmic Strength Varying Wi-Fi Environment

Directory of Open Access Journals (Sweden)

Mu Zhou

2014-01-01

Full Text Available This paper studies the statistical errors for the fingerprint-based RADAR neighbor matching localization with the linearly calibrated reference points (RPs in logarithmic received signal strength (RSS varying Wi-Fi environment. To the best of our knowledge, little comprehensive analysis work has appeared on the error performance of neighbor matching localization with respect to the deployment of RPs. However, in order to achieve the efficient and reliable location-based services (LBSs as well as the ubiquitous context-awareness in Wi-Fi environment, much attention has to be paid to the highly accurate and cost-efficient localization systems. To this end, the statistical errors by the widely used neighbor matching localization are significantly discussed in this paper to examine the inherent mathematical relations between the localization errors and the locations of RPs by using a basic linear logarithmic strength varying model. Furthermore, based on the mathematical demonstrations and some testing results, the closed-form solutions to the statistical errors by RADAR neighbor matching localization can be an effective tool to explore alternative deployment of fingerprint-based neighbor matching localization systems in the future.

Error Analysis for RADAR Neighbor Matching Localization in Linear Logarithmic Strength Varying Wi-Fi Environment

Science.gov (United States)

Tian, Zengshan; Xu, Kunjie; Yu, Xiang

2014-01-01

This paper studies the statistical errors for the fingerprint-based RADAR neighbor matching localization with the linearly calibrated reference points (RPs) in logarithmic received signal strength (RSS) varying Wi-Fi environment. To the best of our knowledge, little comprehensive analysis work has appeared on the error performance of neighbor matching localization with respect to the deployment of RPs. However, in order to achieve the efficient and reliable location-based services (LBSs) as well as the ubiquitous context-awareness in Wi-Fi environment, much attention has to be paid to the highly accurate and cost-efficient localization systems. To this end, the statistical errors by the widely used neighbor matching localization are significantly discussed in this paper to examine the inherent mathematical relations between the localization errors and the locations of RPs by using a basic linear logarithmic strength varying model. Furthermore, based on the mathematical demonstrations and some testing results, the closed-form solutions to the statistical errors by RADAR neighbor matching localization can be an effective tool to explore alternative deployment of fingerprint-based neighbor matching localization systems in the future. PMID:24683349

The structure of a three-dimensional boundary layer subjected to streamwise-varying spanwise-homogeneous pressure gradient

International Nuclear Information System (INIS)

Bentaleb, Y.; Leschziner, M.A.

2013-01-01

Highlights: • We study a spatially-evolving three-dimensional boundary layer. • We impose a streamwise-varying spanwise-homogeneous pressure gradient. • A collateral flow is formed close to the wall, and this is investigated alongside the skewed upper part of the boundary layer. • A wide range of flow-physical properties have been studied. -- Abstract: A spatially-evolving three-dimensional boundary layer, subjected to a streamwise-varying spanwise-homogeneous pressure gradient, equivalent to a body force, is investigated by way of direct numerical simulation. The pressure gradient, prescribed to change its sign half-way along the boundary layer, provokes strong skewing of the velocity vector, with a layer of nearly collateral flow forming close to the wall up to the position of maximum spanwise velocity. A wide range of flow-physical properties have been studied, with particular emphasis on the near-wall layer, including second-moments, major budget contributions and wall-normal two-point correlations of velocity fluctuations and their angles, relative to wall-shear fluctuations. The results illustrate the complexity caused by skewing, including a damping in turbulent mixing and a significant lag between strains and stresses. The study has been undertaken in the context of efforts to develop and test novel hybrid LES–RANS schemes for non-equilibrium near-wall flows, with an emphasis on three-dimensional near-wall straining. Fundamental flow-physical issues aside, the data derived should be of particular relevance to a priori studies of second-moment RANS closure and the development and validation of RANS-type near-wall approximations implemented in LES schemes for high-Reynolds-number complex flows

Physico-chemical analysis and calorific values of poultry manure.

Science.gov (United States)

Quiroga, G; Castrillón, L; Fernández-Nava, Y; Marañón, E

2010-05-01

Spain is one of the major producers of broilers and laying hens in the European Union, with an overall market share of around 12%. The poultry manure that is produced is usually employed as fertilizer on cropland, either directly or after a composting process. In some cases, however, this waste is transported over 120km to be used as fertilizer, with the resulting high transport costs. In other countries, poultry manure is used as an alternative natural fuel source for power generation. In this study, poultry manure from all the laying hen farms in Asturias was characterized with a view to its possible use as an energy source. The Higher Heating Values on a dry basis (experimental) varies between 12,052 and 13,882kJ/kg. Lower Heating Values (LHVs) on a wet basis range are much lower (mean values of 2664kJ/kg) due to the high moisture content of poultry manure. Accordingly, the co-combustion of this waste with other types of waste such as forest and wood waste (LHV on a wet basis of 8044 and 15,830kJ/kg, respectively) or municipal solid waste (LHV on a wet basis of 10,725kJ/kg) should be considered as an alternative energy source. Chlorine and sulphur contents in dry matter vary around mean values of 0.64% and 0.11%, respectively. The waste also presents high amounts of Ca (4.84%) and K (2.38%). Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Wide-Gap Chalcopyrites

CERN Document Server

Siebentritt, Susanne

2006-01-01

Chalcopyrites, in particular those with a wide band gap, are fascinating materials in terms of their technological potential in the next generation of thin-film solar cells and in terms of their basic material properties. They exhibit uniquely low defect formation energies, leading to unusual doping and phase behavior and to extremely benign grain boundaries. This book collects articles on a number of those basic material properties of wide-gap chalcopyrites, comparing them to their low-gap cousins. They explore the doping of the materials, the electronic structure and the transport through interfaces and grain boundaries, the formation of the electric field in a solar cell, the mechanisms and suppression of recombination, the role of inhomogeneities, and the technological role of wide-gap chalcopyrites.

The Relation Between Inflation in Type-I and Type-II Error Rate and Population Divergence in Genome-Wide Association Analysis of Multi-Ethnic Populations.

Science.gov (United States)

Derks, E M; Zwinderman, A H; Gamazon, E R

2017-05-01

Population divergence impacts the degree of population stratification in Genome Wide Association Studies. We aim to: (i) investigate type-I error rate as a function of population divergence (F ST ) in multi-ethnic (admixed) populations; (ii) evaluate the statistical power and effect size estimates; and (iii) investigate the impact of population stratification on the results of gene-based analyses. Quantitative phenotypes were simulated. Type-I error rate was investigated for Single Nucleotide Polymorphisms (SNPs) with varying levels of F ST between the ancestral European and African populations. Type-II error rate was investigated for a SNP characterized by a high value of F ST . In all tests, genomic MDS components were included to correct for population stratification. Type-I and type-II error rate was adequately controlled in a population that included two distinct ethnic populations but not in admixed samples. Statistical power was reduced in the admixed samples. Gene-based tests showed no residual inflation in type-I error rate.

The Value of Fictional Worlds (or Why 'The Lord of the Rings' is Worth Reading

Directory of Open Access Journals (Sweden)

James Harold

2010-01-01

Full Text Available Some works of fiction are widely held by critics to have little value, yet these works are not only popular but also widely admired in ways that are not always appreciated. In this paper I make use of Kendall Walton’s account of fictional worlds to argue that fictional worlds can and often do have value, including aesthetic value, that is independent of the works that create them. In the process, I critique Walton’s notion of fictional worlds and offer a defense of the study and appreciation of fictional worlds, as distinguished from the works of fiction with which they are associated.

What determines how top managers value their stock options?

NARCIS (Netherlands)

Sautner, Z.; Weber, M.

2008-01-01

What determines how top managers value their executive stock options? We explore this question empirically by using a unique survey data set which combines subjective option valuation data with a wide set of individual-level variables. Inconsistent with the predictions of theory, individuals in our

The focusing effect of electromagnetic waves in two-dimensional photonic crystals with gradually varying lattice constant

Directory of Open Access Journals (Sweden)

F Bakhshi Garmi

2016-02-01

Full Text Available In this paper we studied the focusing effect of electromagnetic wave in the two-dimensional graded photonic crystal consisting of Silicon rods in the air background with gradually varying lattice constant. The results showed that graded photonic crystal can focus wide beams on a narrow area at frequencies near the lower edge of the band gap, where equal frequency contours are not concave. For calculation of photonic band structure and equal frequency contours, we have used plane wave expansion method and revised plane wave expansion method, respectively. The calculation of the electric and magnetic fields was performed by finite difference time domain method.

Summary of the U.S. specimen matrix for the HFIR 13J varying temperature irradiation capsule

International Nuclear Information System (INIS)

Zinkle, S.J.

1998-01-01

The US specimen matrix for the collaborative DOE/Monbusho HFIR 13J varying temperature irradiation capsule contains two ceramics and 29 different metals, including vanadium alloys, ferritic/martensitic steels, pure iron, austenitic stainless steels, nickel alloys, and copper alloys. This experiment is designed to provide fundamental information on the effects of brief low-temperature excursions on the tensile properties and microstructural evolution of a wide range of materials irradiated at nominal temperatures of 350 and 500 C to a dose of ∼5 dpa. A total of 340 miniature sheet tensile specimens and 274 TEM disks are included in the US-supplied matrix for the irradiation capsule

Value at Risk as a Diagnostic Tool for Corporates: The Airline Industry

NARCIS (Netherlands)

W.G.P.M. Hallerbach (Winfried); A.J. Menkveld (Bert)

1999-01-01

textabstractIn recent years the Value at Risk (VaR) concept for measuring downside risk has been widely studied. VaR basically is a summary statistic that quantifies the exposure of an asset or portfolio to market risk, or the risk that a position declines in value with adverse market price changes.

Eestlased Karlovy Varys / J. R.

Index Scriptorium Estoniae

J. R.

2007-01-01

Ilmar Raagi mängufilm "Klass" osaleb 42. Karlovy Vary rahvusvahelise filmifestivali võistlusprogrammis "East of the West" ja Asko Kase lühimängufilm "Zen läbi prügi" on valitud festivali kõrvalprogrammi "Forum of Independents"

Understanding Customer Loyalty in the Age of Value: A Study on Malaysian Consumers

OpenAIRE

Teo, Maybelline Kiat Hui

2007-01-01

The competitive environment today has resulted in proliferation of choices offered to consumers, rendering the traditional marketing strategy questionable. Consequently, value-based management has become the hot topic by firms, integrating customer value into operations throughout the entire value chain. It has been widely researched that customer value is an important source of competitive edge for firms to be successful as they are able to generate customer loyalty to increase their share o...

SHOK—The First Russian Wide-Field Optical Camera in Space

Science.gov (United States)

Lipunov, V. M.; Gorbovskoy, E. S.; Kornilov, V. G.; Panasyuk, M. I.; Amelushkin, A. M.; Petrov, V. L.; Yashin, I. V.; Svertilov, S. I.; Vedenkin, N. N.

2018-02-01

Onboard the spacecraft Lomonosov is established two fast, fixed, very wide-field cameras SHOK. The main goal of this experiment is the observation of GRB optical emission before, synchronously, and after the gamma-ray emission. The field of view of each of the cameras is placed in the gamma-ray burst detection area of other devices located onboard the "Lomonosov" spacecraft. SHOK provides measurements of optical emissions with a magnitude limit of ˜ 9-10m on a single frame with an exposure of 0.2 seconds. The device is designed for continuous sky monitoring at optical wavelengths in the very wide field of view (1000 square degrees each camera), detection and localization of fast time-varying (transient) optical sources on the celestial sphere, including provisional and synchronous time recording of optical emissions from the gamma-ray burst error boxes, detected by the BDRG device and implemented by a control signal (alert trigger) from the BDRG. The Lomonosov spacecraft has two identical devices, SHOK1 and SHOK2. The core of each SHOK device is a fast-speed 11-Megapixel CCD. Each of the SHOK devices represents a monoblock, consisting of a node observations of optical emission, the electronics node, elements of the mechanical construction, and the body.

Ownership Concentration and Market Value of European Banks

DEFF Research Database (Denmark)

Busta, Ildura; Sinani, Evis; Thomsen, Steen

2014-01-01

This paper investigates the relationship between ownership concentration and market value of European banks, and the role of the institutional environment in shaping this relationship. Using GMM dynamic estimator on a sample of European banks over a 13-year period (1993–2005) we find on average...... concentration is positive in Scandinavia. We propose that, besides the legal protection of small investors, the differences in the impact of ownership concentration across the countries could be due to the identity of the predominant owners, i.e. financial institutions in Germany and trusts and foundations...... a negative effect of ownership concentration on bank value, measured by Tobin's Q. However, this effect varies across different institutional settings; while higher ownership concentration results in a lower bank value particularly in the countries belonging to German legal family, the impact of ownership...

Locating tissue collections in tissue economies--deriving value from biomedical research

DEFF Research Database (Denmark)

Tupasela, Aaro Mikael

2006-01-01

sample collections are challenged by varying conceptions of value, as well as structural factors that relate to the combination of different public population information systems in the Finnish research system. Such challenges reflect a tension in the economic aspirations of the ideology of the knowledge...

A hepatitis C virus infection model with time-varying drug effectiveness: solution and analysis.

Directory of Open Access Journals (Sweden)

Jessica M Conway

2014-08-01

Full Text Available Simple models of therapy for viral diseases such as hepatitis C virus (HCV or human immunodeficiency virus assume that, once therapy is started, the drug has a constant effectiveness. More realistic models have assumed either that the drug effectiveness depends on the drug concentration or that the effectiveness varies over time. Here a previously introduced varying-effectiveness (VE model is studied mathematically in the context of HCV infection. We show that while the model is linear, it has no closed-form solution due to the time-varying nature of the effectiveness. We then show that the model can be transformed into a Bessel equation and derive an analytic solution in terms of modified Bessel functions, which are defined as infinite series, with time-varying arguments. Fitting the solution to data from HCV infected patients under therapy has yielded values for the parameters in the model. We show that for biologically realistic parameters, the predicted viral decay on therapy is generally biphasic and resembles that predicted by constant-effectiveness (CE models. We introduce a general method for determining the time at which the transition between decay phases occurs based on calculating the point of maximum curvature of the viral decay curve. For the parameter regimes of interest, we also find approximate solutions for the VE model and establish the asymptotic behavior of the system. We show that the rate of second phase decay is determined by the death rate of infected cells multiplied by the maximum effectiveness of therapy, whereas the rate of first phase decline depends on multiple parameters including the rate of increase of drug effectiveness with time.

Perceptions of the Purpose and Value of the School Improvement Plan Process

Science.gov (United States)

Dunaway, David M.; Kim, Do-Hong; Szad, Elizabeth R.

2012-01-01

The purpose of this research was to determine how teachers and administrators in a successful North Carolina district perceived the purpose and value of a school improvement plan (SIP) and the planning process. The SIP is the accepted best practice for school-wide improvement, and the perceptions of the purpose and value of the process…

THE GOAL OF VALUE-BASED MEDICINE ANALYSES: COMPARABILITY. THE CASE FOR NEOVASCULAR MACULAR DEGENERATION

Science.gov (United States)

Brown, Gary C.; Brown, Melissa M.; Brown, Heidi C.; Kindermann, Sylvia; Sharma, Sanjay

2007-01-01

Purpose To evaluate the comparability of articles in the peer-reviewed literature assessing the (1) patient value and (2) cost-utility (cost-effectiveness) associated with interventions for neovascular age-related macular degeneration (ARMD). Methods A search was performed in the National Library of Medicine database of 16 million peer-reviewed articles using the key words cost-utility, cost-effectiveness, value, verteporfin, pegaptanib, laser photocoagulation, ranibizumab, and therapy. All articles that used an outcome of quality-adjusted life-years (QALYs) were studied in regard to (1) percent improvement in quality of life, (2) utility methodology, (3) utility respondents, (4) types of costs included (eg, direct healthcare, direct nonhealthcare, indirect), (5) cost bases (eg, Medicare, National Health Service in the United Kingdom), and (6) study cost perspective (eg, government, societal, third-party insurer). To qualify as a value-based medicine analysis, the patient value had to be measured using the outcome of the QALYs conferred by respective interventions. As with value-based medicine analyses, patient-based time tradeoff utility analysis had to be utilized, patient utility respondents were necessary, and direct medical costs were used. Results Among 21 cost-utility analyses performed on interventions for neovascular macular degeneration, 15 (71%) met value-based medicine criteria. The 6 others (29%) were not comparable owing to (1) varying utility methodology, (2) varying utility respondents, (3) differing costs utilized, (4) differing cost bases, and (5) varying study perspectives. Among value-based medicine studies, laser photocoagulation confers a 4.4% value gain (improvement in quality of life) for the treatment of classic subfoveal choroidal neovascularization. Intravitreal pegaptanib confers a 5.9% value gain (improvement in quality of life) for classic, minimally classic, and occult subfoveal choroidal neovascularization, and photodynamic therapy

The goal of value-based medicine analyses: comparability. The case for neovascular macular degeneration.

Science.gov (United States)

Brown, Gary C; Brown, Melissa M; Brown, Heidi C; Kindermann, Sylvia; Sharma, Sanjay

2007-01-01

To evaluate the comparability of articles in the peer-reviewed literature assessing the (1) patient value and (2) cost-utility (cost-effectiveness) associated with interventions for neovascular age-related macular degeneration (ARMD). A search was performed in the National Library of Medicine database of 16 million peer-reviewed articles using the key words cost-utility, cost-effectiveness, value, verteporfin, pegaptanib, laser photocoagulation, ranibizumab, and therapy. All articles that used an outcome of quality-adjusted life-years (QALYs) were studied in regard to (1) percent improvement in quality of life, (2) utility methodology, (3) utility respondents, (4) types of costs included (eg, direct healthcare, direct nonhealthcare, indirect), (5) cost bases (eg, Medicare, National Health Service in the United Kingdom), and (6) study cost perspective (eg, government, societal, third-party insurer). To qualify as a value-based medicine analysis, the patient value had to be measured using the outcome of the QALYs conferred by respective interventions. As with value-based medicine analyses, patient-based time tradeoff utility analysis had to be utilized, patient utility respondents were necessary, and direct medical costs were used. Among 21 cost-utility analyses performed on interventions for neovascular macular degeneration, 15 (71%) met value-based medicine criteria. The 6 others (29%) were not comparable owing to (1) varying utility methodology, (2) varying utility respondents, (3) differing costs utilized, (4) differing cost bases, and (5) varying study perspectives. Among value-based medicine studies, laser photocoagulation confers a 4.4% value gain (improvement in quality of life) for the treatment of classic subfoveal choroidal neovascularization. Intravitreal pegaptanib confers a 5.9% value gain (improvement in quality of life) for classic, minimally classic, and occult subfoveal choroidal neovascularization, and photodynamic therapy with verteporfin confers

Worldwide Regulations of Standard Values of Pesticides for Human Health Risk Control: A Review

Science.gov (United States)

Jennings, Aaron

2017-01-01

The impact of pesticide residues on human health is a worldwide problem, as human exposure to pesticides can occur through ingestion, inhalation, and dermal contact. Regulatory jurisdictions have promulgated the standard values for pesticides in residential soil, air, drinking water, and agricultural commodity for years. Until now, more than 19,400 pesticide soil regulatory guidance values (RGVs) and 5400 pesticide drinking water maximum concentration levels (MCLs) have been regulated by 54 and 102 nations, respectively. Over 90 nations have provided pesticide agricultural commodity maximum residue limits (MRLs) for at least one of the 12 most commonly consumed agricultural foods. A total of 22 pesticides have been regulated with more than 100 soil RGVs, and 25 pesticides have more than 100 drinking water MCLs. This research indicates that those RGVs and MCLs for an individual pesticide could vary over seven (DDT drinking water MCLs), eight (Lindane soil RGVs), or even nine (Dieldrin soil RGVs) orders of magnitude. Human health risk uncertainty bounds and the implied total exposure mass burden model were applied to analyze the most commonly regulated and used pesticides for human health risk control. For the top 27 commonly regulated pesticides in soil, there are at least 300 RGVs (8% of the total) that are above all of the computed upper bounds for human health risk uncertainty. For the top 29 most-commonly regulated pesticides in drinking water, at least 172 drinking water MCLs (5% of the total) exceed the computed upper bounds for human health risk uncertainty; while for the 14 most widely used pesticides, there are at least 310 computed implied dose limits (28.0% of the total) that are above the acceptable daily intake values. The results show that some worldwide standard values were not derived conservatively enough to avoid human health risk by the pesticides, and that some values were not computed comprehensively by considering all major human exposure

Worldwide Regulations of Standard Values of Pesticides for Human Health Risk Control: A Review.

Science.gov (United States)

Li, Zijian; Jennings, Aaron

2017-07-22

Abstract : The impact of pesticide residues on human health is a worldwide problem, as human exposure to pesticides can occur through ingestion, inhalation, and dermal contact. Regulatory jurisdictions have promulgated the standard values for pesticides in residential soil, air, drinking water, and agricultural commodity for years. Until now, more than 19,400 pesticide soil regulatory guidance values (RGVs) and 5400 pesticide drinking water maximum concentration levels (MCLs) have been regulated by 54 and 102 nations, respectively. Over 90 nations have provided pesticide agricultural commodity maximum residue limits (MRLs) for at least one of the 12 most commonly consumed agricultural foods. A total of 22 pesticides have been regulated with more than 100 soil RGVs, and 25 pesticides have more than 100 drinking water MCLs. This research indicates that those RGVs and MCLs for an individual pesticide could vary over seven (DDT drinking water MCLs), eight (Lindane soil RGVs), or even nine (Dieldrin soil RGVs) orders of magnitude. Human health risk uncertainty bounds and the implied total exposure mass burden model were applied to analyze the most commonly regulated and used pesticides for human health risk control. For the top 27 commonly regulated pesticides in soil, there are at least 300 RGVs (8% of the total) that are above all of the computed upper bounds for human health risk uncertainty. For the top 29 most-commonly regulated pesticides in drinking water, at least 172 drinking water MCLs (5% of the total) exceed the computed upper bounds for human health risk uncertainty; while for the 14 most widely used pesticides, there are at least 310 computed implied dose limits (28.0% of the total) that are above the acceptable daily intake values. The results show that some worldwide standard values were not derived conservatively enough to avoid human health risk by the pesticides, and that some values were not computed comprehensively by considering all major human

Marketingový mix HC Enegie Karlovy Vary

OpenAIRE

Štrobl, Adam

2016-01-01

Title: Marketing mix of HC Energie Karlovy Vary Objectives: This thesis is based on a questionnaire responses obtained from HC Energie Karlovy Vary fans. Its objective is focused on evaluation of their opinions on the marketing mix, their subsequent interpretation, and finally even development of recommendations for improvement based on previous analysis. Methods: Two methods are used to analyse the marketing mix. The first method is qualitative participant observation. The second method is a...

Õunpuu Karlovy Varys edukas

Index Scriptorium Estoniae

2010-01-01

45. Karlovy Vary filmifestivali võistlusprogrammis "East of the West" märgiti ära Veiko Õunpuu film "Püha Tõnu kiusamine". Peaauhind läks rumeenlase Cristi Puiu filmile "Aurora". Grand prix´sai Augustĺ Vila film "La mosquitera". Teisi preemiasaajaid

High historical values of foEs—Reality or artefact?

Science.gov (United States)

Laštovička, J.; Boška, J.; Burešová, D.; Kouba, D.

2012-01-01

Very high values of foEs had sometimes been reported in the past. These values, as well as all other ionogram-scaled values, had been derived from ionograms under the assumption of the vertical reflection of ordinary mode of sounding radio waves. In the past it was impossible to check the validity of this assumption. However, modern digisondes determine clearly the oblique or extraordinary mode reflections. To test the assumption of the vertical reflection of ordinary mode for high values of foEs, seven summers (June 2004-August 2010) from a midlatitude station Pruhonice are chosen. All hourly values of foEs≥6.0 MHz are selected from this data set, altogether 282 values. In 90% of cases the “classical” way of evaluation of foEs provides values higher than “true” values from modern digisonde (average difference about 1 MHz). 38% of “classical” foEs are oblique reflections, which however do not occur in direction perpendicular to geomagnetic field. The occurrence of high values of foEs varies very much from year to year between 0 and 130 events per year. As for diurnal variation, a pronounced maximum occurs at ˜10:00LT and 16:00LT (secondary), and a minimum after midnight.

Assessment of a surface-layer parameterization scheme in an atmospheric model for varying meteorological conditions

Directory of Open Access Journals (Sweden)

T. J. Anurose

2014-06-01

Full Text Available The performance of a surface-layer parameterization scheme in a high-resolution regional model (HRM is carried out by comparing the model-simulated sensible heat flux (H with the concurrent in situ measurements recorded at Thiruvananthapuram (8.5° N, 76.9° E, a coastal station in India. With a view to examining the role of atmospheric stability in conjunction with the roughness lengths in the determination of heat exchange coefficient (CH and H for varying meteorological conditions, the model simulations are repeated by assigning different values to the ratio of momentum and thermal roughness lengths (i.e. z0m/z0h in three distinct configurations of the surface-layer scheme designed for the present study. These three configurations resulted in differential behaviour for the varying meteorological conditions, which is attributed to the sensitivity of CH to the bulk Richardson number (RiB under extremely unstable, near-neutral and stable stratification of the atmosphere.

Analysis of the Prandtl Number Impact on the Temperature Recovery Factor Value

Directory of Open Access Journals (Sweden)

S. A. Burtsev

2017-01-01

Full Text Available The article analyses a design procedure for the gas-dynamic energy separation device and shows that its performance efficiency is mainly dependent on the temperature recovery factor values r.As a result of the performed analysis it was found, that the r values depend on a wide range of parameters, namely Mach and Reynolds number values, gas flow type, axial pressure gradient presence and its magnitude, surface relief, etc. At the same time Prandtl number is the parameter, which has the greatest effect on the r value.A review of correlations available in publications to calculate r values is conducted for Prandtl number values equal to or less than 1 (which is consistent almost with all pure gases and their mixtures and the obtained calculation results are compared with analytical expressions and available experimental data (for laminar and turbulent air flows, turbulent helium and hydrogen-argon mixture flow.It is shown that for laminar boundary layer the correlation of square root of Prandtl number is in good agreement with the experimental and analytical data.For turbulent flows the most widely known correlations were studied, and it was found, that for Prandtl number values equal to or less than 1 all of them lead to errors of at least 10 % and more.A new correlation for r calculation with respect to Prandtl number is proposed with maximum error of 1,5 % for Prandtl number values equal to or less than 1.

Adaptive value of sex in microbial pathogens.

Science.gov (United States)

Michod, Richard E; Bernstein, Harris; Nedelcu, Aurora M

2008-05-01

Explaining the adaptive value of sex is one of the great outstanding problems in biology. The challenge comes from the difficulty in identifying the benefits provided by sex, which must outweigh the substantial costs of sex. Here, we consider the adaptive value of sex in viruses, bacteria and fungi, and particularly the information available on the adaptive role of sex in pathogenic microorganisms. Our general theme is that the varied aspects of sex in pathogens illustrate the varied issues surrounding the evolution of sex generally. These include, the benefits of sex (in the short- and long-term), as well as the costs of sex (both to the host and to the pathogen). For the benefits of sex (that is, its adaptive value), we consider three hypotheses: (i) sex provides for effective and efficient recombinational repair of DNA damages, (ii) sex provides DNA for food, and (iii) sex produces variation and reduces genetic associations among alleles under selection. Although the evolution of sex in microbial pathogens illustrates these general issues, our paper is not a general review of theories for the evolution of sex in all organisms. Rather, we focus on the adaptive value of sex in microbial pathogens and conclude that in terms of short-term benefits, the DNA repair hypothesis has the most support and is the most generally applicable hypothesis in this group. In particular, recombinational repair of DNA damages may substantially benefit pathogens when challenged by the oxidative defenses of the host. However, in the long-term, sex may help get rid of mutations, increase the rate of adaptation of the population, and, in pathogens, may infrequently create new infective strains. An additional general issue about sex illustrated by pathogens is that some of the most interesting consequences of sex are not necessarily the reasons for which sex evolved. For example, antibiotic resistance may be transferred by bacterial sex, but this transfer is probably not the reason sex

Response of Spectral Reflectances and Vegetation Indices on Varying Juniper Cone Densities

Directory of Open Access Journals (Sweden)

Guillermo E. Ponce-Campos

2013-10-01

Full Text Available Juniper trees are widely distributed throughout the world and are common sources of allergies when microscopic pollen grains are transported by wind and inhaled. In this study, we investigated the spectral influences of pollen-discharging male juniper cones within a juniper canopy. This was done through a controlled outdoor experiment involving ASD FieldSpec Pro Spectroradiometer measurements over juniper canopies of varying cone densities. Broadband and narrowband spectral reflectance and vegetation index (VI patterns were evaluated as to their sensitivity and their ability to discriminate the presence of cones. The overall aim of this research was to assess remotely sensed phenological capabilities to detect pollen-bearing juniper trees for public health applications. A general decrease in reflectance values with increasing juniper cone density was found, particularly in the Green (545–565 nm and NIR (750–1,350 nm regions. In contrast, reflectances in the shortwave-infrared (SWIR, 2,000 nm to 2,350 nm region decreased from no cone presence to intermediate amounts (90 g/m2 and then increased from intermediate levels to the highest cone densities (200 g/m2. Reflectance patterns in the Red (620–700 nm were more complex due to shifting contrast patterns in absorptance between cones and juniper foliage, where juniper foliage is more absorbing than cones only within the intense narrowband region of maximum chlorophyll absorption near 680 nm. Overall, narrowband reflectances were more sensitive to cone density changes than the equivalent MODIS broadbands. In all VIs analyzed, there were significant relationships with cone density levels, particularly with the narrowband versions and the two-band vegetation index (TBVI based on Green and Red bands, a promising outcome for the use of phenocams in juniper phenology trait studies. These results indicate that spectral indices are sensitive to certain juniper phenologic traits that can potentially be

[Food value of the spiruline algae to man].

Science.gov (United States)

Sautier, C; Tremolieres, J

1975-01-01

The acceptability of various culinary products based on the algae spirulina was tested by questionaire: formulas rich in proteins, soups, omelets, desserts. Spirulina are little appreciated in France due to offensive color, smell and taste. Tomato and chocolate are the most acceptable flavors. Lyophilisation is preferable to atomisation, and discoloration using alcohol is preferable to the acetone method. The hydrolysate obtained, having neither the smell nor the taste of algae, is excellent. Nitrogen, sodium and potassium balances were recorded in 5 undernourished subjects fed via a gastric tube. The spirulina provided respectively 15 p. 100 (1 subject), 30 p. 100 (2 subjects), and 50 p. 100 (2 subjects) of the protein ration. There were no intestinal problems. The spirulina did not modify the investigated balances. However, faecal nitrogen increased to 2.08 g (compared to control period values, 1.33 g and 1.51 g). The various coefficients: digestibility, nitrogen retention and protein utilization did not vary. In man as in animals, nitrogen retention is satisfactory, but digestibility is diminished. Uric acid did not vary in the urine, but serum values increased slightly. Ingestion of spirulina in small doses even over a long period should be tolerable in the normal subject.

Firm-specific information, analysts’ superiority and investment value

Institute of Scientific and Technical Information of China (English)

Lu; Li; Erjia; Yang; Tusheng; Xiao

2014-01-01

Using a sample of Chinese security analysts’recommendations from 2005 to2010,we examine the source of analysts’superiority and the investment value of their recommendations.Using a calendar-time portfolio approach,we find that,on average,analysts’recommendations are valuable and that analysts are better at analyzing and transferring firm-specific information than market-wide or industry-level information.In addition,we show that the investment value of recommendations increases as firm-specific information becomes more important in stock pricing.Our empirical results are useful in guiding investors and helping brokerage houses to evaluate the output of research departments.

Boys, girls, and the school cultural environment: Teachers' judgment and students' values.

Science.gov (United States)

Aelenei, Cristina; Darnon, Céline; Martinot, Delphine

2017-01-01

Due to gender socialization, girls are more likely to endorse self-transcendence values (e.g., helping people) compared to boys, whereas boys are more likely to endorse self-enhancement values (e.g., wanting to be in charge) compared to girls. In two studies, we investigated teachers' judgment regarding the display of these values in school and students' endorsement of the self-transcendence and self-enhancement values in two contexts: home and school. In Study 1 (N = 240), teachers evaluated a student perceived as strongly endorsing the self-transcendence values more positively compared to a student perceived as strongly endorsing the self-enhancement values, regardless of the student's gender. In Study 2 (N = 151), boys endorsed the self-enhancement values more than the self-transcendence values at home, whereas the opposite occurred in the school context. Girls did not vary across contexts, endorsing the self-transcendence values more than the self-enhancement values in both contexts. Possible consequences on boys' school-related outcomes are discussed.

Individualism-Collectivism: Links to Occupational Plans and Work Values

Science.gov (United States)

Hartung, Paul J.; Fouad, Nadya A.; Leong, Frederick T. L.; Hardin, Erin E.

2010-01-01

Individualism-collectivism (IC) constitutes a cultural variable thought to influence a wide variety of variables including career planning and decision making. To examine this possibility, college students (216 women, 106 men, 64% racial-ethnic minorities) responded to measures of IC, occupational plans, and work values. Multivariate analysis of…

A 43-level filterless CMLI with very low harmonics values

Directory of Open Access Journals (Sweden)

Mahmoud El-Bakry

2014-12-01

Full Text Available This paper introduces a 43-level asymmetric uniform step cascaded multilevel inverter (CMLI that consists of four H-bridges per phase, with different dc sources of values E, 2E, 7E and 11E. A mixed integer linear programming (MILP optimization model is applied to determine the switching angles of the CMLI power switches that can minimize the values of any undesired harmonics. Single phase and three phase cases are considered. The results show very low values of all the undesired harmonics over wide voltage ranges, which agree with the IEEE standards 519-1992 for voltage distortion limits for both the values of %THDE and %VHmax so that no output filters are needed.

Role of different negative pressure values in the process of infected wounds treated by vacuum-assisted closure: an experimental study.

Science.gov (United States)

Zhou, Min; Yu, Aixi; Wu, Gang; Xia, Chengyan; Hu, Xiang; Qi, Baiwen

2013-10-01

Vacuum-assisted closure (VAC) device is widely used to treat infected wounds in clinical work. Although the effect of VAC with different negative pressure values is well established, whether different negative pressures could result in varying modulation of wound relative cytokines was not clear. We hypothesise that instead of the highest negative pressure value the suitable value for VAC is the one which is the most effective on regulating wound relative cytokines. Infected wounds created on pigs' back were used to investigate the effects of varying negative pressure values of VAC devices. Wounds were treated with VAC of different negative pressure values or moist gauze, which was set as control. The VAC foam, semiocclusive dresses and moist gauze were changed on days 3, 5, 7 and 9 after wounds were created. When changing dressings, tissues from wounds were harvested for bacteria count and histology examination including Masson's trichrome stain and immunohistochemistry for microvessels. Western blot was carried out to test the expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF). Results showed that on days 3 and 5 the number of bacteria in wounds treated by VAC with 75, 150, 225 and 300 mmHg was significantly decreased compared with that in wounds treated by gauze and 0 mmHg pressure value. However, there was no difference in wounds treated with negative pressure values of 75 , 150, 225 and 300 mmHg at any time spot. Immunohistochemistry showed that more microvessels were generated in wounds treated by VAC using 75 and 150 mmHg negative pressure comparing with that using 225 and 300 mmHg on days 3 and 5. However this difference vanished on days 7 and 9. Morphological evaluation by Masson's trichrome staining showed increased collagen deposition in VAC of 75 and 150 mmHg compared with that in VAC of 225 and 300 mmHg. Western blot showed that the expression of VEGF and bFGF significantly increased when the wounds

A statistical theory of cell killing by radiation of varying linear energy transfer

International Nuclear Information System (INIS)

Hawkins, R.B.

1994-01-01

A theory is presented that provides an explanation for the observed features of the survival of cultured cells after exposure to densely ionizing high-linear energy transfer (LET) radiation. It starts from a phenomenological postulate based on the linear-quadratic form of cell survival observed for low-LET radiation and uses principles of statistics and fluctuation theory to demonstrate that the effect of varying LET on cell survival can be attributed to random variation of dose to small volumes contained within the nucleus. A simple relation is presented for surviving fraction of cells after exposure to radiation of varying LET that depends on the α and β parameters for the same cells in the limit of low-LET radiation. This relation implies that the value of β is independent of LET. Agreement of the theory with selected observations of cell survival from the literature is demonstrated. A relation is presented that gives relative biological effectiveness (RBE) as a function of the α and β parameters for low-LET radiation. Measurements from microdosimetry are used to estimate the size of the subnuclear volume to which the fluctuation pertains. 11 refs., 4 figs., 2 tabs

Religious Values and Conflict of Laws

Directory of Open Access Journals (Sweden)

Sara Tonolo

2016-02-01

Abstract: The wide evolution of private international law is currently recalling attention to the general aspects of the discipline. Europeanization and globalisation of sources of private international law do not preclude the chance that conflict of laws should also deal with individual identities. To the extent that the European systems have hitherto offered to the application of foreign laws, we are faced with the problem of survival in Europe of an idea of the personality of laws. In fact it’s generally accepted that conflict of laws faces the individual identities of people involved in international relations. Cultural identity may be considered collective and individual at the same time, because each member of the group has an identity of its own. Religious values ontribute to defining the cultural identity of individuals: be it in Europe or other countries, cultures, values, civilization, religion, are never absent from the solutions of personal status. Stepping back from the analysis of some cases where religious values are relevant, this Article aims at a theoretical analysis of the subject, involving the contrast between value pluralism, conflict of laws and fundamental rights.

DIAGNOSTIC VALUE OF SEROLOGICAL MARKERS OF RHEUMATOID ARTHRITIS

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Aleksei Leonidovich Maslaynski

2012-01-01

Full Text Available Rheumatoid arthritis (RA is a classic autoimmune disease associated with the production of wide range of autoantibodies, and their detection has diagnostic and prognostic implication. The objective of this study was to estimate the diagnostic value of antibodies against modified citrullinated vimentin (AMCV and nuclear antigen RA33 of the IgA rheumatoid factor (RF versus the value of routinely used profile of autoantibodies in diagnostic work-up of RA. Material and methods. 253 patients with RA prehistory of varying duration were included into the study group. The control group was comprised of 92 patients, including patients with seronegative spondyloarthropathies and diffuse connective tissue diseases, as well as sex and age matched healthy controls. Serum levels of IgM and IgA RF, antibodies against cyclic citrullinated peptide (ACCP, ACMV, anti-keratin antibodies (AKA, antibodies against RA33 antigen (ARA33 and antinuclear factor (ANF were measured in all patients and controls. Results and discussion. Diagnostic sensitivity of AMCV equaled 78%, ACCP — 77%, IgM RF — 71%, IgA RF — 43%, AKA — 43%, ARA33 — 31% and ANF — 31%. All anti-citrullinic antibodies (AKA, ACCP, ACMV were significantly more commonly associated with IgM RF. Among RF and ACCP seronegative patients ACMV were found in 24% cases with 20 IU/Ml detection threshold, and in 21% — with 30 IU/Ml, allowing to increase diagnostic specificity of the test up to 91% with the increment of diagnostic threshold. Incidence of ARA33 was not significantly different among the RF and ACCP positive or negative subgroups, thus making ARA33 an independent RA marker. Specificity of this marker was 87,9%, thus making it inferior to RF and ACCP by a composite of diagnostic characteristics. Conclusions. Integrated measurement of ACMV and ARA33 is a rational approach at the second stage of serologic testing work-up in suspected cases of RA onset, when initial RF and ACCP tests were negative.

Customer Lifetime and After Lifetime Value - Calculations from an Iranian perspective

DEFF Research Database (Denmark)

Hollensen, Svend; Wilson, Jonathan A.J.; Ebrahimi, Mehdi

2011-01-01

Customer Lifetime Value (CLV) is an established relationship marketing-centric approach to evaluating the significance of a customer, and what resources should be allocated towards maintaining relations – beyond short-term transactional views. The conceptual argument presented in this paper...... contributes one very simple, yet significant argument, which is both transactional and relational. Namely, a large portion of humanity believes in a life beyond current existence – the Afterlife. Therefore, death in the psyche of such a person does not terminate benefit seeking, and there is value...... in the afterlife. The aim here, is to refine value-based calculations, drawing from varying religious perspectives: reincarnation, heaven, and enlightenment, amongst others....

Design and implementation of multi-signal and time-varying neural reconstructions.

Science.gov (United States)

Nanda, Sumit; Chen, Hanbo; Das, Ravi; Bhattacharjee, Shatabdi; Cuntz, Hermann; Torben-Nielsen, Benjamin; Peng, Hanchuan; Cox, Daniel N; De Schutter, Erik; Ascoli, Giorgio A

2018-01-23

Several efficient procedures exist to digitally trace neuronal structure from light microscopy, and mature community resources have emerged to store, share, and analyze these datasets. In contrast, the quantification of intracellular distributions and morphological dynamics is not yet standardized. Current widespread descriptions of neuron morphology are static and inadequate for subcellular characterizations. We introduce a new file format to represent multichannel information as well as an open-source Vaa3D plugin to acquire this type of data. Next we define a novel data structure to capture morphological dynamics, and demonstrate its application to different time-lapse experiments. Importantly, we designed both innovations as judicious extensions of the classic SWC format, thus ensuring full back-compatibility with popular visualization and modeling tools. We then deploy the combined multichannel/time-varying reconstruction system on developing neurons in live Drosophila larvae by digitally tracing fluorescently labeled cytoskeletal components along with overall dendritic morphology as they changed over time. This same design is also suitable for quantifying dendritic calcium dynamics and tracking arbor-wide movement of any subcellular substrate of interest.

Critical values in hematology of 862 institutions in China.

Science.gov (United States)

Ye, Y Y; Zhao, H J; Fei, Y; Wang, W; He, F L; Zhong, K; Yuan, S; Wang, Z G

2017-10-01

A national survey on critical values in hematology of China laboratories was conducted to determine the current practice and assess the quality indicators so as to obtain a quality improvement. Laboratories participating were asked to submit the general information, the practice of critical value reporting, and the status of timeliness of critical value reporting. A total of 862 laboratories submitted the results. The majority of participants have included white blood cell count, blood platelet count, hemoglobin, prothrombin time, and activated partial thromboplastin time in their critical value lists. Many sources are used for establishing a critical value policy, and some of the laboratories consult with clinicians. The unreported critical value rate, late critical value reporting rate, and clinically unacknowledged rate in China are relatively low, and the median of critical value reporting time is 8-9 minutes. There exists a wide variety for critical value reporting in hematology in China. Laboratories should establish a policy of critical value reporting suited for their own situations and consult with clinicians to set critical value lists. Critical values are generally reported in a timely manner in China, but some measures should be taken to further improve the timeliness of critical value reporting. © 2017 John Wiley & Sons Ltd.

Oxidative stability and ignition quality of algae derived methyl esters containing varying levels of methyl eicosapentaenoate and methyl docosahexaenoate

Science.gov (United States)

Bucy, Harrison

Microalgae is currently receiving strong consideration as a potential biofuel feedstock to help meet the advanced biofuels mandate of the 2007 Energy Independence and Security Act because of its theoretically high yield (gallons/acre/year) in comparison to current terrestrial feedstocks. Additionally, microalgae also do not compete with food and can be cultivated with wastewater on non-arable land. Microalgae lipids can be converted into a variety of biofuels including fatty acid methyl esters (e.g. FAME biodiesel), renewable diesel, renewable gasoline, or jet fuel. For microalgae derived FAME, the fuel properties will be directly related to the fatty acid composition of the lipids produced by the given microalgae strain. Several microalgae species under consideration for wide scale cultivation, such as Nannochloropsis, produce lipids with fatty acid compositions containing substantially higher quantities of long chainpolyunsaturated fatty acids (LC-PUFA) in comparison to terrestrial feedstocks. It is expected that increased levels of LC-PUFA will be problematic in terms of meeting all of the current ASTM specifications for biodiesel. For example, it is known that oxidative stability and cetane number decrease with increasing levels of LC-PUFA. However, these same LC-PUFA fatty acids, such as eicosapentaenoic acid (EPA: C20:5) and docosahexaenoic acid (DHA: C22:6) are known to have high nutritional value thereby making separation of these compounds economically attractive. Given the uncertainty in the future value of these LC-PUFA compounds and the economic viability of the separation process, the goal of this study was to examine the oxidative stability and ignition quality of algae-based FAME with varying levels of EPA and DHA removal. Oxidative stability tests were conducted at a temperature of 110°C and airflow of 10 L/h using a Metrohm 743 Rancimat with automatic induction period determination following the EN 14112 Method from the ASTM D6751 and EN 14214

Using latent variable approach to estimate China's economy-wide energy rebound effect over 1954–2010

International Nuclear Information System (INIS)

Shao, Shuai; Huang, Tao; Yang, Lili

2014-01-01

The energy rebound effect has been a significant issue in China, which is undergoing economic transition, since it reflects the effectiveness of energy-saving policy relying on improved energy efficiency. Based on the IPAT equation and Brookes' explanation of the rebound effect, this paper develops an alternative estimation model of the rebound effect. By using the estimation model and latent variable approach, which is achieved through a time-varying coefficient state space model, we estimate China's economy-wide energy rebound effect over 1954–2010. The results show that the rebound effect evidently exists in China as a result of the annual average of 39.73% over 1954–2010. Before and after the implementation of China's reform and opening-up policy in 1978, the rebound effects are 47.24% and 37.32%, with a strong fluctuation and a circuitously downward trend, respectively, indicating that a stable political environment and the development of market economy system facilitate the effectiveness of energy-saving policy. Although the energy-saving effect of improving energy efficiency has been partly realised, there remains a large energy-saving potential in China. - Highlights: • We present an improved estimation methodology of economy-wide energy rebound effect. • We use the latent variable approach to estimate China's economy-wide rebound effect. • The rebound exists in China and varies before and after reform and opening-up. • After 1978, the average rebound is 37.32% with a circuitously downward trend. • Traditional Solow remainder method underestimates the rebound in most cases

ARCHITECTURAL CONCEPTS FOR VALUE CHAINS

Directory of Open Access Journals (Sweden)

A.C. Janse van Rensburg

2012-01-01

Full Text Available

ENGLISH ABSTRACT:The Porter Value Chain has been widely adopted by the business community as a mechanism to understand and comprehend complexity in business environments, with the ultimate goal of structuring the business to maximize its competitive advantage. Implementing the Value Chain is not easy: a number of organizations can testify to their failure to derive any benefits at all from this concept. To overcome this problem, an approach is presented to assist the organization in creating a Value Chain reference model within the broader context of the organization’s enterprise architecture.

AFRIKAANSE OPSOMMING: Die “Porter Waardeketting” is ’n algemene aanvaarde praktyk wat deur maatskappye gebruik word om die kompleksiteit van besigheidsomgewings mee te verstaan. Die uiteindelike doel hiervan is om die besigheid se mededings voordele te optimiseer. Om die Waardekettingkonsep te implementeer, is nie ’n maklike taak nie – verskeie organisasies kan getuig van mislukte implementeringspogings. Hierdie artikel beskryf ’n benadering beskryf wat gebruik kan word om die organisasie te help om ’n Waardekettingmodel te skep in die bree konteks van die organisasie se besigheidsargitektuur.

Congruence of Personal and Organizational Values: Moving Beyond Practice

Directory of Open Access Journals (Sweden)

Jolita Vveinhardt

2017-06-01

Full Text Available The purpose of this paper is to review and clarify the knowledge of practice related literature on the concept of congruence between personal and organizational values and to develop the framework for strengthening the congruence between personal and organizational values in order to improve understanding about how the theory is turned into practice. This paper thoroughly analyses an extensive literature in relation to value congruence and its practical management and discusses the relationships between theoretical knowledge and practical implications. By organizing a wide range of practice related aspects into meaningful categories, the paper presents specific practical suggestions how to strengthen the congruence of personal and organizational values. The paper gives clear practical guidance for those who intend to develop and implement the congruence between personal and organizational values, since the model may be useful in selecting the most suitable practices for specific situations in organizations.

Distribution of Microsatellite instability in Danish ovarian tumor patients and the prognostic value in ovarian cancer patients

DEFF Research Database (Denmark)

Begum, F.D.; Kjaer, S.K.; Blaakaer, J.

2008-01-01

The repeated frequency of microsatellite instability (MSI) in ovarian cancer (OC) ranges from 0% to 50%. Most MSI studies including OC patients have involved relatively small number of tumors, a wide range of different MSI markers, different patient characteristics, and varying criteria for defin...

Integrated management model. Methodology and software-enabled tood designed to assist a utility in developing a station-wide optimization

International Nuclear Information System (INIS)

Llovet, R.; Ibanez, R.; Woodcock, J.

2005-01-01

A key concern for utilities today is optimizing station aging and realibility management activities in a manner that maximizes the value of those activities withing an affordable budget. The Westinghouse Proactive Asset Management Model is a methodology and software-enabled tood designed to assist a utility in developing a station-wide optimization of those activities. The process and tool support the development of an optimized, station-wide plan for inspection, testing, maintenance, repaor and replacement of aging components. The optimization identifies the benefit and optimal timing of those activities based on minimizing unplanned outage costs (avoided costs) and maximizing station Net Present Value. (Author)

Generating Sustainable Value from Open Data in a Sharing Society

DEFF Research Database (Denmark)

Jetzek, Thorhildur; Avital, Michel; Bjørn-Andersen, Niels

2014-01-01

Our societies are in the midst of a paradigm shift that transforms hierarchical markets into an open and networked economy based on digital technology and information. In that context, open data is widely presumed to have a positive effect on social, environmental and economic value; however...... the evidence to that effect has remained scarce. Subsequently, we address the question how the use of open data can stimulate the generation of sustainable value. We argue that open data sharing and reuse can empower new ways of generating value in the sharing society. Moreover, we propose a model...... that describes how different mechanisms that take part within an open system generate sustainable value. These mechanisms are enabled by a number of contextual factors that provide individuals with the motivation, opportunity and ability to generate sustainable value...

Contrast and autoshaping in multiple schedules varying reinforcer rate and duration.

Science.gov (United States)

Hamilton, B E; Silberberg, A

1978-07-01

Thirteen master pigeons were exposed to multiple schedules in which reinforcement frequency (Experiment I) or duration (Experiment II) was varied. In Phases 1 and 3 of Experiment I, the values of the first and second components' random-interval schedules were 33 and 99 seconds, respectively. In Phase 2, these values were 99 seconds for both components. In Experiment II, a random-interval 33-second schedule was associated with each component. During Phases 1 and 3, the first and second components had hopper durations of 7.5 and 2.5 seconds respectively. During Phase 2, both components' hopper durations were 2.5 seconds. In each experiment, positive contrast obtained for about half the master subjects. The rest showed a rate increase in both components (positive induction). Each master subject's key colors and reinforcers were synchronously presented on a response-independent basis to a yoked control. Richer component key-pecking occurred during each experiment's Phases 1 and 3 among half these subjects. However, none responded during the contrast condition (unchanged component of each experiment's Phase 2). From this it is inferred that autoshaping did not contribute to the contrast and induction findings among master birds. Little evidence of local contrast (highest rate at beginning of richer component) was found in any subject. These data show that (a) contrast can occur independently from autoshaping, (b) contrast assays during equal-valued components may produce induction, (c) local contrast in multiple schedules often does not occur, and (d) differential hopper durations can produce autoshaping and contrast.

Optimistlik Karlovy Vary / Jaan Ruus

Index Scriptorium Estoniae

Ruus, Jaan, 1938-2017

2007-01-01

42. Karlovy Vary rahvusvahelise filmifestivali auhinnatud filmidest (žürii esimees Peter Bart). Kristallgloobuse sai Islandi-Saksamaa "Katseklaasilinn" (režii Baltasar Kormakur), parimaks režissööriks tunnistati norralane Bard Breien ("Negatiivse mõtlemise kunst"). Austraallase Michael James Rowlandi "Hea õnne teekond" sai žürii eripreemia

Subjective value of risky foods for individual domestic chicks: a hierarchical Bayesian model.

Science.gov (United States)

Kawamori, Ai; Matsushima, Toshiya

2010-05-01

For animals to decide which prey to attack, the gain and delay of the food item must be integrated in a value function. However, the subjective value is not obtained by expected profitability when it is accompanied by risk. To estimate the subjective value, we examined choices in a cross-shaped maze with two colored feeders in domestic chicks. When tested by a reversal in food amount or delay, chicks changed choices similarly in both conditions (experiment 1). We therefore examined risk sensitivity for amount and delay (experiment 2) by supplying one feeder with food of fixed profitability and the alternative feeder with high- or low-profitability food at equal probability. Profitability varied in amount (groups 1 and 2 at high and low variance) or in delay (group 3). To find the equilibrium, the amount (groups 1 and 2) or delay (group 3) of the food in the fixed feeder was adjusted in a total of 18 blocks. The Markov chain Monte Carlo method was applied to a hierarchical Bayesian model to estimate the subjective value. Chicks undervalued the variable feeder in group 1 and were indifferent in group 2 but overvalued the variable feeder in group 3 at a population level. Re-examination without the titration procedure (experiment 3) suggested that the subjective value was not absolute for each option. When the delay was varied, the variable option was often given a paradoxically high value depending on fixed alternative. Therefore, the basic assumption of the uniquely determined value function might be questioned.

Evolution of perturbation in charge-varying dusty plasmas

International Nuclear Information System (INIS)

Popel, S.I.; Golub, A.P.; Losseva, T.V.; Bingham, R.; Benkadda, S.

2001-01-01

The nonstationary problem of the evolution of perturbation and its transformation into nonlinear wave structure in dusty plasmas is considered. For this purpose two one-dimensional models based on a set of fluid equations, Poisson's equation, and a charging equation for dust are developed. The first (simplified) model corresponds to the case [Popel et al., Phys. Plasmas 3, 4313 (1996)] when exact steady-state shock wave solutions can exist. This simplified model includes variable-charged dust grains, Boltzmann electrons, and inertial ions. The second (ionization source) model takes into account the variation of the ion density and the ion momentum dissipation due to dust particle charging as well as the source of plasma particles due to ionization process. The computational method for solving the set of equations which describe the evolution in time of a nonlinear structure in a charge-varying dusty plasma is developed. The case of the evolution of an intensive initial nonmoving region with a constant enhanced ion density is investigated on the basis of these two models. The consideration within the ionization source model is performed for the data of the laboratory experiment [Luo et al., Phys. Plasmas 6, 3455 (1999)]. It is shown that the ionization source model allows one to obtain shock structures as a result of evolution of an initial perturbation and to explain the experimental value of the width of the shock wave front. Comparison of the numerical data obtained on the basis of the ionization source model and the simplified model shows that the main characteristic features of the shock structure are the same for both models. Nevertheless, the ionization source model is much more sensitive to the form of the initial perturbation than the simplified model. The solution of the problem of the evolution of perturbation and its transformation into shock wave in charge-varying dusty plasmas opens up possibilities for description of the real phenomena like supernova

A Design of Wide Band and Wide Beam Cavity-Backed Slot Antenna Array with Slant Polarization

Directory of Open Access Journals (Sweden)

Huiying Qi

2016-01-01

Full Text Available Design of antenna array under the limitation of restricted size is a challenging problem. Cavity-backed slot antenna is widely used because of its advantages of small size, wide band, and wide beam. In this paper, a design of wide band and wide beam cavity-backed slot antenna array with the slant polarization is proposed. To obtain wide band and wide beam with limited size, the inverted microstrip-fed cavity-backed slot antenna (IMF-CBSA is adopted as the element of 1 × 4 antenna array. The slant polarized antennas and their feeding networks are adopted because of their simple structures. The performance of the proposed antenna array is verified by the simulations and experiments. The measured VSWR < 2 bandwidth is 55% at the center frequency 21.8 GHz, and the gain is larger than 12.2 dB. Experimental results demonstrate that the proposed design achieves wide band and beam with the size of 68 mm × 56 mm × 14.5 mm.

Species richness alone does not predict cultural ecosystem service value

Science.gov (United States)

Graves, Rose A.; Pearson, Scott M.; Turner, Monica G.

2017-01-01

Many biodiversity-ecosystem services studies omit cultural ecosystem services (CES) or use species richness as a proxy and assume that more species confer greater CES value. We studied wildflower viewing, a key biodiversity-based CES in amenity-based landscapes, in Southern Appalachian Mountain forests and asked (i) How do aesthetic preferences for wildflower communities vary with components of biodiversity, including species richness?; (ii) How do aesthetic preferences for wildflower communities vary across psychographic groups?; and (iii) How well does species richness perform as an indicator of CES value compared with revealed social preferences for wildflower communities? Public forest visitors (n = 293) were surveyed during the summer of 2015 and asked to choose among images of wildflower communities in which flower species richness, flower abundance, species evenness, color diversity, and presence of charismatic species had been digitally manipulated. Aesthetic preferences among images were unrelated to species richness but increased with more abundant flowers, greater species evenness, and greater color diversity. Aesthetic preferences were consistent across psychographic groups and unaffected by knowledge of local flora or value placed on wildflower viewing. When actual wildflower communities (n = 54) were ranked based on empirically measured flower species richness or wildflower viewing utility based on multinomial logit models of revealed preferences, rankings were broadly similar. However, designation of hotspots (CES values above the median) based on species richness alone missed 27% of wildflower viewing utility hotspots. Thus, conservation priorities for sustaining CES should incorporate social preferences and consider multiple dimensions of biodiversity that underpin CES supply. PMID:28320953

Sensitivity analysis of socio-economic values of time for public transport projects

DEFF Research Database (Denmark)

Andersen, Jonas Lohmann Elkjær; Landex, Alex; Nielsen, Otto Anker

2007-01-01

The socio-economic time benefits of two light rail projects in Copenhagen are investigated using three different sets of values of time. The first set is the one the Ministry of Transport recommends for use in socio-economic analysis in Denmark; this is used as basis for comparison with the two...... recommended by the Ministry of Transport. Differentiated in-vehicle values prove to generate an even higher increase in time benefits, but vary depending on the projects....

A Genome-Wide Association Study Primer for Clinicians

Directory of Open Access Journals (Sweden)

Tzu-Hao Wang

2009-06-01

Full Text Available Genome-wide association studies (GWAS use high-throughput genotyping technology to relate hundreds of thousands of genetic markers (genotypes to clinical conditions and measurable traits (phenotypes. This review is intended to serve as an introduction to GWAS for clinicians, to allow them to better appreciate the value and limitations of GWAS for genotype-disease association studies. The input of clinicians is vital for GWAS, since disease heterogeneity is frequently a confounding factor that can only really be solved by clinicians. For diseases that are difficult to diagnose, clinicians should ensure that the cases do indeed have the disease; for common diseases, clinicians should ensure that the controls are truly disease-free.

DCF Fair Value Valuation, Excessive Assetes and Hidden Inefficiencies

Directory of Open Access Journals (Sweden)

Paweł Mielcarz

2011-12-01

Full Text Available Fair value concept is widely used in DCF (Discounted Cash Flow  business valuation. One of the main principle of fair value concept is full information symmetry between contracting parties. The assumption enforces specific way of FCF (Free Cash Flow estimation: all areas of inefficiency of valuated companies should be identified and their effect on free cash flow should be eliminated. The projection of free cash flow thus prepared should reflect the optimum operations of the business. The methodological issues of fair value valuation of inefficient companies are not comprehensibly addressed in the financial and accounting literature. There is easily observable gap between fair value theory and valuation practices. Thus this article is an attempt to answer the question about practical issues in fair value valuation of companies which do not apply value based management rules. It is based on literature review, theory examination and short case studies which present proposed solution for practical problems. Methods of identification and assessment of impact of inefficiencies on the fair value of a business are hereinafter presented and supported with arguments.

Value chains for biorefineries of wastes from food production and services - ValueWaste

Energy Technology Data Exchange (ETDEWEB)

Kahiluoto, H.; Kuisma, M.; Knuuttila, M. (and others) (MTT Agrifood Research Finland, Mikkeli (Finland)). Email: helena.kahiluoto@mtt.fi

2010-10-15

The aim of the ValueWaste project is to analyse biomass potentials, appropriate technologies and business opportunities. Contrasting regional scenarios for biorefinery activities are developed, and their overall sustainability is assessed: environmental impacts using life cycle assessment, impacts on regional economy, partnership in actor chains, as well as business opportunities and possibilities for commercialisation are considered. South Savo and partly Satakunta provide the case study regions, but the project also produces tools for generalisation and contributes to national solutions. The theoretical potentials suggest that the agrifood waste has a significant and currently untapped potential for replacing non-renewable energy and recycling nutrients, and further for climate and water protection. The volume of agrifood waste varies mainly according to animal husbandry, crop production and food processing of a region. New business opportunities were found from the value chain of biowaste flows in the area of Etelae-Savo. Unexploited raw materials and new methods in waste collection and transportation offer entrepreneurial opportunities and decrease the costs of operation. Based on the conceptual work for creation of the contrasting regional biorefinery scenarios, performed in workshops for project and steering group members, four different optimisation starting points were determined: 1) replacement of fossil energy; 2) maximisation of carbon sequestration; 3) water protection and 4) enhancement of regional economy. Present situation of the biomass utilisation in the region was adopted as the baseline scenario. Four contrasting, consistent scenarios for the value chain of waste-based biorefineries are formed in South Savo. (orig.)

Re-identification of persons in multi-camera surveillance under varying viewpoints and illumination

Science.gov (United States)

Bouma, Henri; Borsboom, Sander; den Hollander, Richard J. M.; Landsmeer, Sander H.; Worring, Marcel

2012-06-01

The capability to track individuals in CCTV cameras is important for surveillance and forensics alike. However, it is laborious to do over multiple cameras. Therefore, an automated system is desirable. In literature several methods have been proposed, but their robustness against varying viewpoints and illumination is limited. Hence performance in realistic settings is also limited. In this paper, we present a novel method for the automatic re-identification of persons in video from surveillance cameras in a realistic setting. The method is computationally efficient, robust to a wide variety of viewpoints and illumination, simple to implement and it requires no training. We compare the performance of our method to several state-of-the-art methods on a publically available dataset that contains the variety of viewpoints and illumination to allow benchmarking. The results indicate that our method shows good performance and enables a human operator to track persons five times faster.

Experimental evidence for amplitude death induced by a time-varying interaction

Energy Technology Data Exchange (ETDEWEB)

Suresh, K. [Centre for Nonlinear Dynamics, School of Physics, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu (India); Shrimali, M.D. [Department of Physics, Central University of Rajasthan, NH-8, Bandar Sindri, Ajmer 305 801 (India); Prasad, Awadhesh [Department of Physics and Astrophysics, University of Delhi, Delhi 110 007 (India); Thamilmaran, K., E-mail: maran.cnld@gmail.com [Centre for Nonlinear Dynamics, School of Physics, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu (India)

2014-08-01

In this paper, we study the time-varying interaction in coupled oscillatory systems. For this purpose, we have designed a novel time-varying resistive network using an analog switch and inverter circuits. We have applied this time-varying resistive network to mutually coupled identical Chua's oscillators. When the resistances are varied in time, we find that amplitude death arises in coupled identical oscillators. This has been observed numerically as well as verified through hardware experiments. - Highlights: • We have implemented the time-varying interaction in coupled oscillatory systems. • We have designed a novel time-varying resistive network using an analog switch and inverter circuits. • When the resistances are varied in time, we find that amplitude death arises in coupled identical oscillators.

Brane world cosmologies with varying speed of light

International Nuclear Information System (INIS)

Youm, Donam

2001-02-01

We study cosmologies in the Randall-Sundrum models, incorporating the possibility of time-varying speed of light and Newton's constant. The cosmologies with varying speed of light (VSL) were proposed by Moffat and by Albrecht and Magueijo as an alternative to inflation for solving the cosmological problems. We consider the case in which the speed of light varies with time after the radion or the scale of the extra dimension has been stabilized. We elaborate on the conditions under which the flatness problem and the cosmological constant problem can be resolved. Particularly, the VSL cosmologies may provide a possible mechanism for bringing the quantum corrections to the fine-tuned brane tensions after the SUSY breaking under control. (author)

Disruption of soil aggregates by varied amounts of ultrasonic energy in fractionation of organic matter of a clay latosol : carbon, nitrogen and 13C distribution in particle-size fractions

NARCIS (Netherlands)

Roscoe, R.; Buurman, P.; Velthorst, E.J.

2000-01-01

Ultrasonic energy has been widely used to disrupt soil aggregates before fractionating soil physically when studying soil organic matter (SOM). Nevertheless, there is no consensus about the optimum energy desirable to disrupt the soil. We therefore aimed (i) to quantify the effect of varied

Service quality and perceived customer value in community pharmacies.

Science.gov (United States)

Guhl, Dennis; Blankart, Katharina E; Stargardt, Tom

2018-01-01

A patient's perception of the service provided by a health care provider is essential for the successful delivery of health care. This study examines the value created by community pharmacies-defined as perceived customer value-in the prescription drug market through varying elements of service quality. We develop a path model that describes the relationship between service elements and perceived customer value. We then analyze the effect of perceived customer value on customer satisfaction and loyalty. We use data obtained from 289 standardized interviews on respondents' prescription fill in the last six months in Germany. The service elements personal interaction (path coefficient: 0.31), physical aspect (0.12), store policy (0.24), and availability (0.1) have a positive significant effect on perceived customer value. Consultation and reliability have no significant influence. We further find a strong positive interdependency between perceived customer value, customer satisfaction (0.75), and customer loyalty (0.71). Thus, pharmacies may enhance customer satisfaction and loyalty if they consider the customer perspective and focus on the relevant service elements. To enhance benefit, personal interaction appears to be most important to address appropriately.

A set-valued approach to FDI and FTC: Theory and implementation issues

DEFF Research Database (Denmark)

Rosa, Paulo Andre Nobre; Casau, Pedro; Silvestre, Carlos

2012-01-01

A complete methodology to design robust Fault Detection and Isolation (FDI) filters and Fault Tolerant Control (FTC) schemes for Linear Time-Varying (LTV) systems is proposed. The paper takes advantage of the recent advances in model invalidation using Set-Valued Observers (SVOs) that led...

Robust wide-range control of nuclear reactors by using the feedforward-feedback concept

International Nuclear Information System (INIS)

Weng, C.K.; Edwards, R.M.; Ray, A.

1994-01-01

A robust feedforward-feedback controller is proposed for wide-range operations of nuclear reactors. This control structure provides (a) optimized performance over a wide operating range resulting form the feedforward element and (b) guaranteed robust stability and performance resulting from the feedback element. The feedforward control law is synthesized via nonlinear programming, which generates an optimal control sequence over a finite-time horizon under specified constraints. The feedback control is synthesized via the structured singular value μ approach to guarantee robustness in the presence of disturbances and modeling uncertainties. The results of simulation experiments are presented to demonstrate efficacy of the proposed control structure for a large rapid power reduction to avoid unnecessary plant trips

Observational constraints on holographic dark energy with varying gravitational constant

Energy Technology Data Exchange (ETDEWEB)

Lu, Jianbo; Xu, Lixin [Institute of Theoretical Physics, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian, 116024 (China); Saridakis, Emmanuel N. [College of Mathematics and Physics, Chongqing University of Posts and Telecommunications, Chongqing, 400065 (China); Setare, M.R., E-mail: lvjianbo819@163.com, E-mail: msaridak@phys.uoa.gr, E-mail: rezakord@ipm.ir, E-mail: lxxu@dlut.edu.cn [Department of Science of Bijar, University of Kurdistan, Bijar (Iran, Islamic Republic of)

2010-03-01

We use observational data from Type Ia Supernovae (SN), Baryon Acoustic Oscillations (BAO), Cosmic Microwave Background (CMB) and observational Hubble data (OHD), and the Markov Chain Monte Carlo (MCMC) method, to constrain the cosmological scenario of holographic dark energy with varying gravitational constant. We consider both flat and non-flat background geometry, and we present the corresponding constraints and contour-plots of the model parameters. We conclude that the scenario is compatible with observations. In 1σ we find Ω{sub Λ0} = 0.72{sup +0.03}{sub −0.03}, Ω{sub k0} = −0.0013{sup +0.0130}{sub −0.0040}, c = 0.80{sup +0.19}{sub −0.14} and Δ{sub G}≡G'/G = −0.0025{sup +0.0080}{sub −0.0050}, while for the present value of the dark energy equation-of-state parameter we obtain w{sub 0} = −1.04{sup +0.15}{sub −0.20}.

Are preference and resistance to change convergent expressions of stimulus value?

Science.gov (United States)

Podlesnik, Christopher A; Jimenez-Gomez, Corina; Shahan, Timothy A

2013-07-01

Behavioral momentum theory asserts that preference and relative resistance to disruption depend on reinforcement rates and provide converging expressions of the conditioned value of discriminative stimuli. However, preference and resistance to disruption diverge when assessing preference during brief extinction probes. We expanded upon this opposing relation by arranging target stimuli signaling equal variable-interval schedules across components of a multiple schedule. We paired one target stimulus with a richer reinforced alternative and the other with a leaner alternative. Furthermore, we varied reinforcement rates for the paired alternatives to assess the effects of manipulating relative conditioned value on preference and resistance to disruption by presession feeding, intercomponent food, and extinction. We replicated the opposing relation between preference and resistance to disruption but varying reinforcement rates for the paired alternatives did not systematically affect preference or resistance to disruption beyond levels observed in our initial condition. Importantly, we found that only preference between the target stimuli was related to relative baseline response rates in the presence of those stimuli. These findings suggest that preference during extinction probes might reveal more about baseline response rates between concurrently available alternatives than relative conditioned value. Resistance to disruption, conversely, appears to better reflect conditioned value because it is less confounded with baseline response rates and is a function of all sources of reinforcement obtained in the presence of a stimulus context. © Society for the Experimental Analysis of Behavior.

Antimicrobial susceptibility testing of Clostridium difficile using EUCAST epidemiological cut-off values and disk diffusion correlates

DEFF Research Database (Denmark)

Erikstrup, L T; Hall, Vanessa Jane; Kahlmeter, G

2012-01-01

towards metronidazole, vancomycin and moxifloxacin on Brucella Blood Agar supplemented with hemin and vitamin K. We found an excellent agreement between inhibition zone diameter and MICs. For each MIC value, the inhibition zones varied from 0 to 8 mm, with 93% of values within 6 mm for metronidazole, 95...

Generalization of the Wide-Sense Markov Concept to a Widely Linear Processing

International Nuclear Information System (INIS)

Espinosa-Pulido, Juan Antonio; Navarro-Moreno, Jesús; Fernández-Alcalá, Rosa María; Ruiz-Molina, Juan Carlos; Oya-Lechuga, Antonia; Ruiz-Fuentes, Nuria

2014-01-01

In this paper we show that the classical definition and the associated characterizations of wide-sense Markov (WSM) signals are not valid for improper complex signals. For that, we propose an extension of the concept of WSM to a widely linear (WL) setting and the study of new characterizations. Specifically, we introduce a new class of signals, called widely linear Markov (WLM) signals, and we analyze some of their properties based either on second-order properties or on state-space models from a WL processing standpoint. The study is performed in both the forwards and backwards directions of time. Thus, we provide two forwards and backwards Markovian representations for WLM signals. Finally, different estimation recursive algorithms are obtained for these models

Valuing Trial Designs from a Pharmaceutical Perspective Using Value-Based Pricing.

Science.gov (United States)

Breeze, Penny; Brennan, Alan

2015-11-01

Our aim was to adapt the traditional framework for expected net benefit of sampling (ENBS) to be more compatible with drug development trials from the pharmaceutical perspective. We modify the traditional framework for conducting ENBS and assume that the price of the drug is conditional on the trial outcomes. We use a value-based pricing (VBP) criterion to determine price conditional on trial data using Bayesian updating of cost-effectiveness (CE) model parameters. We assume that there is a threshold price below which the company would not market the new intervention. We present a case study in which a phase III trial sample size and trial duration are varied. For each trial design, we sampled 10,000 trial outcomes and estimated VBP using a CE model. The expected commercial net benefit is calculated as the expected profits minus the trial costs. A clinical trial with shorter follow-up, and larger sample size, generated the greatest expected commercial net benefit. Increasing the duration of follow-up had a modest impact on profit forecasts. Expected net benefit of sampling can be adapted to value clinical trials in the pharmaceutical industry to optimise the expected commercial net benefit. However, the analyses can be very time consuming for complex CE models. © 2014 The Authors. Health Economics published by John Wiley & Sons Ltd.

Baseline values of immunologic parameters in the lizard Salvator merianae (Teiidae, Squamata)

Science.gov (United States)

Mestre, Ana Paula; Amavet, Patricia Susana; Siroski, Pablo Ariel

2017-01-01

The genus Salvator is widely distributed throughout South America. In Argentina, the species most abundant widely distributed is Salvator merianae. Particularly in Santa Fe province, the area occupied by populations of these lizards overlaps with areas where agriculture was extended. With the aim of established baseline values for four immunologic biomarkers widely used, 36 tegu lizards were evaluated tacking into account different age classes and both sexes. Total leukocyte counts were not different between age classes. Of the leucocytes count, eosinophils levels were higher in neonates compared with juvenile and adults; nevertheless, the heterophils group was the most prevalent leukocyte in the peripheral blood in all age classes. Lymphocytes, monocytes, heterophils, azurophils and basophils levels did not differ with age. Natural antibodies titres were higher in the adults compared with neonates and juveniles lizards. Lastly, complement system activity was low in neonates compared with juveniles and adults. Statistical analysis within each age group showed that gender was not a factor in the outcomes. Based on the results, we concluded that S. merianae demonstrated age (but not gender) related differences in the immune parameters analyzed. Having established baseline values for these four widely-used immunologic biomarkers, ongoing studies will seek to optimize the use of the S. merianae model in future research. PMID:28652981

Baseline values of immunologic parameters in the lizard Salvator merianae (Teiidae, Squamata).

Science.gov (United States)

Mestre, Ana Paula; Amavet, Patricia Susana; Siroski, Pablo Ariel

2017-01-01

The genus Salvator is widely distributed throughout South America. In Argentina, the species most abundant widely distributed is Salvator merianae . Particularly in Santa Fe province, the area occupied by populations of these lizards overlaps with areas where agriculture was extended. With the aim of established baseline values for four immunologic biomarkers widely used, 36 tegu lizards were evaluated tacking into account different age classes and both sexes. Total leukocyte counts were not different between age classes. Of the leucocytes count, eosinophils levels were higher in neonates compared with juvenile and adults; nevertheless, the heterophils group was the most prevalent leukocyte in the peripheral blood in all age classes. Lymphocytes, monocytes, heterophils, azurophils and basophils levels did not differ with age. Natural antibodies titres were higher in the adults compared with neonates and juveniles lizards. Lastly, complement system activity was low in neonates compared with juveniles and adults. Statistical analysis within each age group showed that gender was not a factor in the outcomes. Based on the results, we concluded that S. merianae demonstrated age (but not gender) related differences in the immune parameters analyzed. Having established baseline values for these four widely-used immunologic biomarkers, ongoing studies will seek to optimize the use of the S. merianae model in future research.

Baseline values of immunologic parameters in the lizard Salvator merianae (Teiidae, Squamata

Directory of Open Access Journals (Sweden)

Ana Paula Mestre

2017-05-01

Full Text Available The genus Salvator is widely distributed throughout South America. In Argentina, the species most abundant widely distributed is Salvator merianae. Particularly in Santa Fe province, the area occupied by populations of these lizards overlaps with areas where agriculture was extended. With the aim of established baseline values for four immunologic biomarkers widely used, 36 tegu lizards were evaluated tacking into account different age classes and both sexes. Total leukocyte counts were not different between age classes. Of the leucocytes count, eosinophils levels were higher in neonates compared with juvenile and adults; nevertheless, the heterophils group was the most prevalent leukocyte in the peripheral blood in all age classes. Lymphocytes, monocytes, heterophils, azurophils and basophils levels did not differ with age. Natural antibodies titres were higher in the adults compared with neonates and juveniles lizards. Lastly, complement system activity was low in neonates compared with juveniles and adults. Statistical analysis within each age group showed that gender was not a factor in the outcomes. Based on the results, we concluded that S. merianae demonstrated age (but not gender related differences in the immune parameters analyzed. Having established baseline values for these four widely-used immunologic biomarkers, ongoing studies will seek to optimize the use of the S. merianae model in future research.

The value and potential of multisited ethnography for science education research: a review of Jrène Rahm's Science in the Making at the Margin

Science.gov (United States)

Beeman-Cadwallader, Nicole

2012-03-01

Rahm sought to illuminate how children and youth make meaning of science in three out-of-school time programs, and the identity work that is done through the trajectory of their youth toward their young adulthood. Through using multisited ethnography, she asserts that we can learn more about what the youth say about their science learning and science literacy development in these programs. She has revealed through her rich data the potential value of multisited ethnography for science education research. A similar theme of insider/outsider status to science emerged in each of the three sites. The nature of the data collected in Rahm's multisited ethnography allowed for the unveiling of the similarities in this theme, but also made evident the nuanced ways that this theme presented itself differently across the three sites. The additional potential came through in the varied data Rahm could have delved into and did not. A unique characteristic of ethnographic research, that is not necessarily present in other research methods, is that a wide array of varied data is collected. An analysis of documents, images, and observational field notes, which go beyond interview data, may provide deeper understandings previously untouched in science education.

Rare species are valued big time.

Directory of Open Access Journals (Sweden)

Elena Angulo

Full Text Available BACKGROUND: It has recently been postulated that the value humans place on rarity could cause the extinction of rare species. This is because people are willing to pay the high costs of exploiting the last individuals. Many hobbies, such as ecotourism or the keeping of exotic pets may cause this effect--known as the anthropogenic Allee effect. However, the entire theory relies on the insofar undemonstrated assumption that people do value rarity. METHODOLOGY/PRINCIPAL FINDINGS: In order to quantify how much people valued rare species relative to common ones, we created online slideshows of photographs of either rare or common species on an Internet web site. The slideshow with photographs of rare species attracted more visitors, and visitors spent, in general, more time waiting to view it. CONCLUSIONS/SIGNIFICANCE: We provide evidence that people value rare more than common species. As we did not target consumers of a specific market, this finding suggests that the anthropogenic Allee effect is likely be driven by a large part of the population. Given the substantial participation in our online experiment, we highlight the potential of the world wide web resource as a tool for conservation action. However, the evidence presented here that the general public value rare species, combined with the assumption that anthropogenic Allee effect is operating, implies that conservationists should be prudent when using rarity to promote conservation.

Esmaklassiline Karlovy Vary / Jaanus Noormets

Index Scriptorium Estoniae

Noormets, Jaanus

2007-01-01

Ilmar Raagi mängufilm "Klass" võitis 42. Karlovy Vary rahvusvahelise filmifestivalil kaks auhinda - ametliku kõrvalvõistlusprogrammi "East of the West" eripreemia "Special mention" ja Euroopa väärtfilmikinode keti Europa Cinemas preemia. Ka Asko Kase lühifilmi "Zen läbi prügi linastumisest ning teistest auhinnasaajatest ning osalejatest

Student participation in World Wide Web-based curriculum development of general chemistry

Science.gov (United States)

Hunter, William John Forbes

1998-12-01

This thesis describes an action research investigation of improvements to instruction in General Chemistry at Purdue University. Specifically, the study was conducted to guide continuous reform of curriculum materials delivered via the World Wide Web by involving students, instructors, and curriculum designers. The theoretical framework for this study was based upon constructivist learning theory and knowledge claims were developed using an inductive analysis procedure. This results of this study are assertions made in three domains: learning chemistry content via the World Wide Web, learning about learning via the World Wide Web, and learning about participation in an action research project. In the chemistry content domain, students were able to learn chemical concepts that utilized 3-dimensional visualizations, but not textual and graphical information delivered via the Web. In the learning via the Web domain, the use of feedback, the placement of supplementary aids, navigation, and the perception of conceptual novelty were all important to students' use of the Web. In the participation in action research domain, students learned about the complexity of curriculum. development, and valued their empowerment as part of the process.

Expectancy-value theory in persistence of learning effects in schizophrenia: role of task value and perceived competency.

Science.gov (United States)

Choi, Jimmy; Fiszdon, Joanna M; Medalia, Alice

2010-09-01

Expectancy-value theory, a widely accepted model of motivation, posits that expectations of success on a learning task and the individual value placed on the task are central determinants of motivation to learn. This is supported by research in healthy controls suggesting that beliefs of self-and-content mastery can be so influential they can predict the degree of improvement on challenging cognitive tasks even more so than general cognitive ability. We examined components of expectancy-value theory (perceived competency and task value), along with baseline arithmetic performance and neuropsychological performance, as possible predictors of learning outcome in a sample of 70 outpatients with schizophrenia randomized to 1 of 2 different arithmetic learning conditions and followed up after 3 months. Results indicated that as with nonpsychiatric samples, perceived self-competency for the learning task was significantly related to perceptions of task value attributed to the learning task. Baseline expectations of success predicted persistence of learning on the task at 3-month follow-up, even after accounting for variance attributable to different arithmetic instruction, baseline arithmetic ability, attention, and self-reports of task interest and task value. We also found that expectation of success is a malleable construct, with posttraining improvements persisting at follow-up. These findings support the notion that expectancy-value theory is operative in schizophrenia. Thus, similar to the nonpsychiatric population, treatment benefits may be enhanced and better maintained if remediation programs also focus on perceptions of self-competency for the training tasks. Treatment issues related to instilling self-efficacy in cognitive recovery programs are discussed.

Valuing Manggarai Station – Soekarno-Hatta International Airport Rail Link Using Stated Preference Approach

Directory of Open Access Journals (Sweden)

Wahyu Tamtomo Adi

2015-06-01

The segmented models results vary that the value of male is higher than female, the value of high income is higher than low income, the values of taxi user is higher than car user, the value of business traveler is higher than leisure and commuter traveler, the value of self-finance journey is lower than the journey paid by the company. With the standard level of service, the probability result of mode sharing shows that the majority of respondents will use the train service (40.99%, followed by the other modes: bus (30.90%, car (16.52%, and taxi (11.59%. Keywords: Jakarta, SHIA airport, access mode, value of in-vehicle time, value of waiting time, model segmentation, mode sharing.

Children's perceived cost for exercise: application of an expectancy-value paradigm.

Science.gov (United States)

Chiang, Evelyn S; Byrd, Sandra P; Molin, Ashley J

2011-04-01

Expectancy-value models of motivation have been applied to understanding children's choices in areas such as academics and sports. Here, an expectancy-value paradigm is applied to exercising (defined as engaging in physical activity). The notion of perceived cost is highlighted in particular. Two hundred twenty children in third, fourth, and fifth grades were surveyed on their competence beliefs, perceived importance, interest, and perceived cost of being physically active. Results indicated that perceived cost is empirically distinct from competence beliefs and other types of value, that perceived cost is marginally related to children's self-reported level of physical activity, and children's beliefs and other values are related to their self-reported level of physical activity. Children's perceptions of cost vary depending on grade and gender. Interventions based on these findings are proposed.

The design and q resolution of the small and wide angle neutron scattering instrument (TAIKAN) in J-PARC

International Nuclear Information System (INIS)

Takata, Shin-ichi; Suzuki, Jun-ichi; Shinohara, Takenao; Oku, Takayuki; Tominaga, Taiki; Nakatani, Takeshi; Inamura, Yasuhiro; Suzuya, Kentaro; Aizawa, Kazuya; Arai, Masatoshi; Ohishi, Kazuki; Iwase, Hiroki; Ito, Takayoshi; Otomo, Toshiya; Sugiyama, Masaaki

2015-01-01

The small and wide angle neutron scattering instrument (TAIKAN) is designed to cover the wide q range of 0.005 0.3 Å"-"1 with the other banks. The q resolution was compared with the values experimentally obtained from the widths of Bragg peaks of a standard sample, silver behenate. The results of the experiment were consistent with the theory. It was confirmed that TAIKAN was completed as was expected. (author)

Anistropically varying conductivity in irreversible electroporation simulations.

Science.gov (United States)

Labarbera, Nicholas; Drapaca, Corina

2017-11-01

One recent area of cancer research is irreversible electroporation (IRE). Irreversible electroporation is a minimally invasive procedure where needle electrodes are inserted into the body to ablate tumor cells with electricity. The aim of this paper is to propose a mathematical model that incorporates a tissue's conductivity increasing more in the direction of the electrical field as this has been shown to occur in experiments. It was necessary to mathematically derive a valid form of the conductivity tensor such that it is dependent on the electrical field direction and can be easily implemented into numerical software. The derivation of a conductivity tensor that can take arbitrary functions for the conductivity in the directions tangent and normal to the electrical field is the main contribution of this paper. Numerical simulations were performed for isotropic-varying and anisotropic-varying conductivities to evaluate the importance of including the electrical field's direction in the formulation for conductivity. By starting from previously published experimental results, this paper derived a general formulation for an anistropic-varying tensor for implementation into irreversible electroporation modeling software. The anistropic-varying tensor formulation allows the conductivity to take into consideration both electrical field direction and magnitude, as opposed to previous published works that only took into account electrical field magnitude. The anisotropic formulation predicts roughly a five percent decrease in ablation size for the monopolar simulation and approximately a ten percent decrease in ablation size for the bipolar simulations. This is a positive result as previously reported results found the isotropic formulation to overpredict ablation size for both monopolar and bipolar simulations. Furthermore, it was also reported that the isotropic formulation overpredicts the ablation size more for the bipolar case than the monopolar case. Thus, our

Risk-premia, Carry-trade Dynamics, and Economic Value of Currency Speculation

DEFF Research Database (Denmark)

Wagner, Christian

2012-01-01

In this paper, we derive the dynamics and assess the economic value of currency speculation by formalizing the concept of a trader inaction range. We show that exchange rate returns comprise a time-varying risk-premium and that uncovered interest parity (UIP) holds in a speculative sense. The often......-cited ‘forward bias puzzle’ originates from the omission of the risk-premium in standard UIP tests. Consistent with its popularity among market professionals, the carry-trade strategy can be rationalized as it systematically collects risk-premia, however, the economic value generated by bilateral carry-trades...

Analysis of time-varying psoriasis lesion image patterns

DEFF Research Database (Denmark)

Maletti, Gabriela Mariel; Ersbøll, Bjarne Kjær; Nielsen, Allan Aasbjerg

2004-01-01

The multivariate alteration detection transform is applied to pairs of within and between time varying registered psoriasis image patterns. Color band contribution to the variates explaining maximal change is analyzed.......The multivariate alteration detection transform is applied to pairs of within and between time varying registered psoriasis image patterns. Color band contribution to the variates explaining maximal change is analyzed....

Specimen loading list for the varying temperature experiment

International Nuclear Information System (INIS)

Qualls, A.L.; Sitterson, R.G.

1998-01-01

The varying temperature experiment HFIR-RB-13J has been assembled and inserted in the reactor. Approximately 5300 specimens were cleaned, inspected, matched, and loaded into four specimen holders. A listing of each specimen loaded into the steady temperature holder, its position in the capsule, and the identification of the corresponding specimen loaded into the varying temperature holder is presented in this report

Wide-Range Adaptive RF-to-DC Power Converter for UHF RFIDs

KAUST Repository

Ouda, Mahmoud H.

2016-07-27

A wide-range, differential, cross-coupled rectifier is proposed with an extended dynamic range of input RF power that enables wireless powering from varying distances. The proposed architecture mitigates the reverse-leakage problem in conven- tional, cross-coupled rectifiers without degrading sensitivity. A prototype is designed for UHF RFID applications, and is imple- mented using 0.18 μ m CMOS technology. On-chip measurements demonstrate a sensitivity of − 18 dBm for 1 V output over a 100 k Ω load and a peak RF-to-DC power conversion efficiency of 65%. A conventional, fully cross-coupled rectifier is fabricated along- side for comparison and the proposed rectifier shows more than 2 × increase in dynamic range and a 25% boosting in output voltage than the conventional rectifier

Generating Sustainable Value from Open Data in a Sharing Society

DEFF Research Database (Denmark)

Jetzek, Thorhildur; Avital, Michel; Bjørn-Andersen, Niels

2014-01-01

Our societies are in the midst of a paradigm shift that transforms hierarchical markets into an open and networked economy based on digital technology and information. In that context, open data is widely presumed to have a positive effect on social, environmental and economic value; however...

Genome wide linkage disequilibrium in Chinese asparagus bean (Vigna. unguiculata ssp. sesquipedialis) germplasm: implications for domestication history and genome wide association studies.

Science.gov (United States)

Xu, P; Wu, X; Wang, B; Luo, J; Liu, Y; Ehlers, J D; Close, T J; Roberts, P A; Lu, Z; Wang, S; Li, G

2012-07-01

Association mapping of important traits of crop plants relies on first understanding the extent and patterns of linkage disequilibrium (LD) in the particular germplasm being investigated. We characterize here the genetic diversity, population structure and genome wide LD patterns in a set of asparagus bean (Vigna. unguiculata ssp. sesquipedialis) germplasm from China. A diverse collection of 99 asparagus bean and normal cowpea accessions were genotyped with 1127 expressed sequence tag-derived single nucleotide polymorphism markers (SNPs). The proportion of polymorphic SNPs across the collection was relatively low (39%), with an average number of SNPs per locus of 1.33. Bayesian population structure analysis indicated two subdivisions within the collection sampled that generally represented the 'standard vegetable' type (subgroup SV) and the 'non-standard vegetable' type (subgroup NSV), respectively. Level of LD (r(2)) was higher and extent of LD persisted longer in subgroup SV than in subgroup NSV, whereas LD decayed rapidly (0-2 cM) in both subgroups. LD decay distance varied among chromosomes, with the longest (≈ 5 cM) five times longer than the shortest (≈ 1 cM). Partitioning of LD variance into within- and between-subgroup components coupled with comparative LD decay analysis suggested that linkage group 5, 7 and 10 may have undergone the most intensive epistatic selection toward traits favorable for vegetable use. This work provides a first population genetic insight into domestication history of asparagus bean and demonstrates the feasibility of mapping complex traits by genome wide association study in asparagus bean using a currently available cowpea SNPs marker platform.

Forecasting the value-at-risk of Chinese stock market using the HARQ model and extreme value theory

Science.gov (United States)

Liu, Guangqiang; Wei, Yu; Chen, Yongfei; Yu, Jiang; Hu, Yang

2018-06-01

Using intraday data of the CSI300 index, this paper discusses value-at-risk (VaR) forecasting of the Chinese stock market from the perspective of high-frequency volatility models. First, we measure the realized volatility (RV) with 5-minute high-frequency returns of the CSI300 index and then model it with the newly introduced heterogeneous autoregressive quarticity (HARQ) model, which can handle the time-varying coefficients of the HAR model. Second, we forecast the out-of-sample VaR of the CSI300 index by combining the HARQ model and extreme value theory (EVT). Finally, using several popular backtesting methods, we compare the VaR forecasting accuracy of HARQ model with other traditional HAR-type models, such as HAR, HAR-J, CHAR, and SHAR. The empirical results show that the novel HARQ model can beat other HAR-type models in forecasting the VaR of the Chinese stock market at various risk levels.

Varied line-space gratings and applications

International Nuclear Information System (INIS)

McKinney, W.R.

1991-01-01

This paper presents a straightforward analytical and numerical method for the design of a specific type of varied line-space grating system. The mathematical development will assume plane or nearly-plane spherical gratings which are illuminated by convergent light, which covers many interesting cases for synchrotron radiation. The gratings discussed will have straight grooves whose spacing varies across the principal plane of the grating. Focal relationships and formulae for the optical grating-pole-to-exist-slit distance and grating radius previously presented by other authors will be derived with a symbolic algebra system. It is intended to provide the optical designer with the tools necessary to design such a system properly. Finally, some possible advantages and disadvantages for application to synchrotron to synchrotron radiation beamlines will be discussed

Robustness Analysis of a Wide-Span Timber Structure with Ductile Behaviour

DEFF Research Database (Denmark)

Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; Cizmar, D.

2010-01-01

This paper considers robustness evaluation of a wide span timber truss structure where the ductile behavior is taken into account. The robustness analysis is based on a structural reliability framework used on a simplified mechanical system modelling a timber truss system. A measure of ductile...... behaviour is introduced and for different values of this measure the robustness indices are estimated. The results indicate that the robustness of a timber truss system can be increased by taking the ductile behavior into....

Anatomy of a value proposition for laboratory medicine.

Science.gov (United States)

Price, Christopher P; St John, Andrew

2014-09-25

Value is now becoming a key driver in the ongoing development of healthcare delivery; key facets include the identification of what is valuable and how that value can be identified, leveraged, and delivered. The concept of a value proposition is widely used in business but can be used in healthcare as a statement of the benefits, costs and value that an organization can deliver to its customers. The foundation of this statement in laboratory medicine is evidence of clinical and cost effectiveness, not only for the patient, but also for other stakeholders involved in the delivery of healthcare, e.g., the carer, service provider, commissioner, purchaser, and the supplier of the test or device, as well as society as a whole. However the value of any laboratory medicine investigation is only achieved if the output (the test result(s)), is acted upon by the initiator of the investigation. Laboratory medicine is one part of a complex intervention, and so the value proposition should encompass the breadth of that intervention - from addressing the unmet need through the generation of clinical, operational and economic outcomes. A value proposition in laboratory medicine is central to successful innovation and quality improvement in healthcare. Copyright © 2014 Elsevier B.V. All rights reserved.

Endocannabinoid and Mood Responses to Exercise in Adults with Varying Activity Levels.

Science.gov (United States)

Brellenthin, Angelique G; Crombie, Kevin M; Hillard, Cecilia J; Koltyn, Kelli F

2017-08-01

Acute aerobic exercise improves mood and activates the endocannabinoid (eCB) system in physically active individuals; however, both mood and eCB responses to exercise may vary based on habitual levels of physical activity. This study aimed to examine eCB and mood responses to prescribed and preferred exercises among individuals with low, moderate, and high levels of physical activity. Thirty-six healthy adults (21 ± 4 yr) were recruited from low (≤60 min moderate-vigorous physical activity [MVPA] per week), moderate (150-299 min MVPA per week), and high (≥300 MVPA per week) physical activity groups. Participants performed both prescribed (approximately 70%-75% max) and preferred (i.e., self-selected) aerobic exercise on separate days. Mood states and eCB concentrations were assessed before and after exercise conditions. Both preferred and prescribed exercise resulted in significant increases (P exercise elicited positive mood improvements compared with preexercise values, but changes in state anxiety, total mood disturbance, and confusion were greater in the preferred condition (P mood disturbance in the preferred condition (P mood or eCB outcomes. These results indicate that eCB and mood responses to exercise do not differ significantly between samples with varying physical activity levels. This study also demonstrates that in addition to prescribed exercise, preferred exercise activates the eCB system, and this activation may contribute to positive mood outcomes with exercise.

Genome-wide characterization of the SiDof gene family in foxtail millet (Setaria italica).

Science.gov (United States)

Zhang, Li; Liu, Baoling; Zheng, Gewen; Zhang, Aiying; Li, Runzhi

2017-01-01

Dof (DNA binding with one finger) proteins, which constitute a class of transcription factors found exclusively in plants, are involved in numerous physiological and biochemical reactions affecting growth and development. A genome-wide analysis of SiDof genes was performed in this study. Thirty five SiDof genes were identified and those genes were unevenly distributed across nine chromosomes in the Seteria italica genome. Protein lengths, molecular weights, and theoretical isoelectric points of SiDofs all vary greatly. Gene structure analysis demonstrated that most SiDof genes lack introns. Phylogenetic analysis of SiDof proteins and Dof proteins from Arabidopsis thaliana, rice, sorghum, and Setaria viridis revealed six major groups. Analysis of RNA-Seq data indicated that SiDof gene expression levels varied across roots, stems, leaves, and spike. In addition, expression profiling of SiDof genes in response to stress suggested that SiDof 7 and SiDof 15 are involved in drought stress signalling. Overall, this study could provide novel information on SiDofs for further investigation in foxtail millet. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Predictive and prognostic value of tumor volume and its changes during radical radiotherapy of stage III non-small cell lung cancer. A systematic review

International Nuclear Information System (INIS)

Kaesmann, Lukas; Niyazi, Maximilian; Fleischmann, Daniel; Blanck, Oliver; Baumann, Rene; Baues, Christian; Klook, Lisa; Rosenbrock, Johannes; Trommer-Nestler, Maike; Dobiasch, Sophie; Eze, Chukwuka; Gauer, Tobias; Goy, Yvonne; Giordano, Frank A.; Sautter, Lisa; Hausmann, Jan; Henkenberens, Christoph; Kaul, David; Thieme, Alexander H.; Krug, David; Schmitt, Daniela; Maeurer, Matthias; Panje, Cedric M.; Suess, Christoph; Ziegler, Sonia; Ebert, Nadja; Medenwald, Daniel; Ostheimer, Christian

2018-01-01

Lung cancer remains the leading cause of cancer-related mortality worldwide. Stage III non-small cell lung cancer (NSCLC) includes heterogeneous presentation of the disease including lymph node involvement and large tumour volumes with infiltration of the mediastinum, heart or spine. In the treatment of stage III NSCLC an interdisciplinary approach including radiotherapy is considered standard of care with acceptable toxicity and improved clinical outcome concerning local control. Furthermore, gross tumour volume (GTV) changes during definitive radiotherapy would allow for adaptive replanning which offers normal tissue sparing and dose escalation. A literature review was conducted to describe the predictive value of GTV changes during definitive radiotherapy especially focussing on overall survival. The literature search was conducted in a two-step review process using PubMed registered /Medline registered with the key words ''stage III non-small cell lung cancer'' and ''radiotherapy'' and ''tumour volume'' and ''prognostic factors''. After final consideration 17, 14 and 9 studies with a total of 2516, 784 and 639 patients on predictive impact of GTV, GTV changes and its impact on overall survival, respectively, for definitive radiotherapy for stage III NSCLC were included in this review. Initial GTV is an important prognostic factor for overall survival in several studies, but the time of evaluation and the value of histology need to be further investigated. GTV changes during RT differ widely, optimal timing for re-evaluation of GTV and their predictive value for prognosis needs to be clarified. The prognostic value of GTV changes is unclear due to varying study qualities, re-evaluation time and conflicting results. The main findings were that the clinical impact of GTV changes during definitive radiotherapy is still unclear due to heterogeneous study designs with varying quality

Evaluating the Solar Slowly Varying Component at C-Band Using Dual- and Single-Polarization Weather Radars in Europe

Directory of Open Access Journals (Sweden)

M. Gabella

2017-01-01

Full Text Available Six C-band weather radars located in Europe (Finland, Netherlands, and Switzerland have been used to monitor the slowly varying solar emission, which is an oscillation with an amplitude of several decibels and a period of approximately 27 days. It is caused by the fact that the number of active regions that enhance the solar radio emission with respect to the quiet component, as seen from Earth, varies because of the Sun’s rotation about its axis. The analysis is based on solar signals contained in the polar volume data produced during the operational weather scan strategy. This paper presents hundreds of daily comparisons between radar estimates and the Sun’s reference signal, during the current active Sun period (year 2014. The Sun’s reference values are accurately measured by the Dominion Radio Astrophysical Observatory (DRAO at S-band and converted to C-band using a standard DRAO formula. Vertical and horizontal polarization receivers are able to capture the monthly oscillation of the solar microwave signal: the standard deviation of the log-transformed ratio between radars and the DRAO reference ranges from 0.26 to 0.4 dB. A larger coefficient (and a different value for the quiet Sun component in the standard formula improves the agreement.

Eesti film võistleb Karlovy Varys

Index Scriptorium Estoniae

2008-01-01

8. juulil esilinastub Karlovy Vary filmifestivalil Rene Vilbre noortefilm "Mina olin siin", mille aluseks on Sass Henno romaan "Mina olin siin. Esimene arest", stsenaariumi kirjutas Ilmar Raag. Film võistleb võistlusprogrammis "East of the West"

Defining landscape resistance values in least-cost connectivity models for the invasive grey squirrel: a comparison of approaches using expert-opinion and habitat suitability modelling.

Science.gov (United States)

Stevenson-Holt, Claire D; Watts, Kevin; Bellamy, Chloe C; Nevin, Owen T; Ramsey, Andrew D

2014-01-01

Least-cost models are widely used to study the functional connectivity of habitat within a varied landscape matrix. A critical step in the process is identifying resistance values for each land cover based upon the facilitating or impeding impact on species movement. Ideally resistance values would be parameterised with empirical data, but due to a shortage of such information, expert-opinion is often used. However, the use of expert-opinion is seen as subjective, human-centric and unreliable. This study derived resistance values from grey squirrel habitat suitability models (HSM) in order to compare the utility and validity of this approach with more traditional, expert-led methods. Models were built and tested with MaxEnt, using squirrel presence records and a categorical land cover map for Cumbria, UK. Predictions on the likelihood of squirrel occurrence within each land cover type were inverted, providing resistance values which were used to parameterise a least-cost model. The resulting habitat networks were measured and compared to those derived from a least-cost model built with previously collated information from experts. The expert-derived and HSM-inferred least-cost networks differ in precision. The HSM-informed networks were smaller and more fragmented because of the higher resistance values attributed to most habitats. These results are discussed in relation to the applicability of both approaches for conservation and management objectives, providing guidance to researchers and practitioners attempting to apply and interpret a least-cost approach to mapping ecological networks.

Defining landscape resistance values in least-cost connectivity models for the invasive grey squirrel: a comparison of approaches using expert-opinion and habitat suitability modelling.

Directory of Open Access Journals (Sweden)

Claire D Stevenson-Holt

Full Text Available Least-cost models are widely used to study the functional connectivity of habitat within a varied landscape matrix. A critical step in the process is identifying resistance values for each land cover based upon the facilitating or impeding impact on species movement. Ideally resistance values would be parameterised with empirical data, but due to a shortage of such information, expert-opinion is often used. However, the use of expert-opinion is seen as subjective, human-centric and unreliable. This study derived resistance values from grey squirrel habitat suitability models (HSM in order to compare the utility and validity of this approach with more traditional, expert-led methods. Models were built and tested with MaxEnt, using squirrel presence records and a categorical land cover map for Cumbria, UK. Predictions on the likelihood of squirrel occurrence within each land cover type were inverted, providing resistance values which were used to parameterise a least-cost model. The resulting habitat networks were measured and compared to those derived from a least-cost model built with previously collated information from experts. The expert-derived and HSM-inferred least-cost networks differ in precision. The HSM-informed networks were smaller and more fragmented because of the higher resistance values attributed to most habitats. These results are discussed in relation to the applicability of both approaches for conservation and management objectives, providing guidance to researchers and practitioners attempting to apply and interpret a least-cost approach to mapping ecological networks.

Critical Values for Lawshe's Content Validity Ratio: Revisiting the Original Methods of Calculation

Science.gov (United States)

Ayre, Colin; Scally, Andrew John

2014-01-01

The content validity ratio originally proposed by Lawshe is widely used to quantify content validity and yet methods used to calculate the original critical values were never reported. Methods for original calculation of critical values are suggested along with tables of exact binomial probabilities.

Validation of Theory of Consumption Values Scales for Deal Sites

DEFF Research Database (Denmark)

Sudzina, Frantisek

2016-01-01

Deal sites became a widely used artefact. But there is still only a limited number of papers investigating their adoption and use. Most of the research published on the topic is qualitative. It is typical for an early stage of investigation of any new artefact. The Theory of Consumption Values ex...... explains purchase behavior. The aim of this paper is to validate scales for the Theory of Consumption Values for deal sites. This should pave a way for quantitative investigation of motives for purchasing using deal sites....

Discrete simulations of spatio-temporal dynamics of small water bodies under varied stream flow discharges

Science.gov (United States)

Daya Sagar, B. S.

2005-01-01

Spatio-temporal patterns of small water bodies (SWBs) under the influence of temporally varied stream flow discharge are simulated in discrete space by employing geomorphologically realistic expansion and contraction transformations. Cascades of expansion-contraction are systematically performed by synchronizing them with stream flow discharge simulated via the logistic map. Templates with definite characteristic information are defined from stream flow discharge pattern as the basis to model the spatio-temporal organization of randomly situated surface water bodies of various sizes and shapes. These spatio-temporal patterns under varied parameters (λs) controlling stream flow discharge patterns are characterized by estimating their fractal dimensions. At various λs, nonlinear control parameters, we show the union of boundaries of water bodies that traverse the water body and non-water body spaces as geomorphic attractors. The computed fractal dimensions of these attractors are 1.58, 1.53, 1.78, 1.76, 1.84, and 1.90, respectively, at λs of 1, 2, 3, 3.46, 3.57, and 3.99. These values are in line with general visual observations.

Discrete simulations of spatio-temporal dynamics of small water bodies under varied stream flow discharges

Directory of Open Access Journals (Sweden)

B. S. Daya Sagar

2005-01-01

Full Text Available Spatio-temporal patterns of small water bodies (SWBs under the influence of temporally varied stream flow discharge are simulated in discrete space by employing geomorphologically realistic expansion and contraction transformations. Cascades of expansion-contraction are systematically performed by synchronizing them with stream flow discharge simulated via the logistic map. Templates with definite characteristic information are defined from stream flow discharge pattern as the basis to model the spatio-temporal organization of randomly situated surface water bodies of various sizes and shapes. These spatio-temporal patterns under varied parameters (λs controlling stream flow discharge patterns are characterized by estimating their fractal dimensions. At various λs, nonlinear control parameters, we show the union of boundaries of water bodies that traverse the water body and non-water body spaces as geomorphic attractors. The computed fractal dimensions of these attractors are 1.58, 1.53, 1.78, 1.76, 1.84, and 1.90, respectively, at λs of 1, 2, 3, 3.46, 3.57, and 3.99. These values are in line with general visual observations.

Entropy Rate of Time-Varying Wireless Networks

DEFF Research Database (Denmark)

Cika, Arta; Badiu, Mihai Alin; Coon, Justin P.

2018-01-01

In this paper, we present a detailed framework to analyze the evolution of the random topology of a time-varying wireless network via the information theoretic notion of entropy rate. We consider a propagation channel varying over time with random node positions in a closed space and Rayleigh...... fading affecting the connections between nodes. The existence of an edge between two nodes at given locations is modeled by a Markov chain, enabling memory effects in network dynamics. We then derive a lower and an upper bound on the entropy rate of the spatiotemporal network. The entropy rate measures...

A Comparison of Tissue Engineering Scaffolds Incorporated with Manuka Honey of Varying UMF

Directory of Open Access Journals (Sweden)

Katherine R. Hixon

2017-01-01

Full Text Available Purpose. Manuka honey (MH is an antibacterial agent specific to the islands of New Zealand containing both hydrogen peroxide and a Unique Manuka Factor (UMF. Although the antibacterial properties of MH have been studied, the effect of varying UMF of MH incorporated into tissue engineered scaffolds have not. Therefore, this study was designed to compare silk fibroin cryogels and electrospun scaffolds incorporated with a 5% MH concentration of various UMF. Methods. Characteristics such as porosity, bacterial clearance and adhesion, and cytotoxicity were compared. Results. Pore diameters for all cryogels were between 51 and 60 µm, while electrospun scaffolds were 10 µm. Cryogels of varying UMF displayed clearance of approximately 0.16 cm for E. coli and S. aureus. In comparison, the electrospun scaffolds clearance ranged between 0.5 and 1 cm. A glucose release of 0.5 mg/mL was observed for the first 24 hours by all scaffolds, regardless of UMF. With respect to cytotoxicity, neither scaffold caused the cell number to drop below 20,000. Conclusions. Overall, when comparing the effects of the various UMF within the two scaffolds, no significant differences were observed. This suggests that the fabricated scaffolds in this study displayed similar bacterial effects regardless of the UMF value.

Feasibility of estimating generalized extreme-value distribution of floods

International Nuclear Information System (INIS)

Ferreira de Queiroz, Manoel Moises

2004-01-01

Flood frequency analysis by generalized extreme-value probability distribution (GEV) has found increased application in recent years, given its flexibility in dealing with the three asymptotic forms of extreme distribution derived from different initial probability distributions. Estimation of higher quantiles of floods is usually accomplished by extrapolating one of the three inverse forms of GEV distribution fitted to the experimental data for return periods much higher than those actually observed. This paper studies the feasibility of fitting GEV distribution by moments of linear combinations of higher order statistics (LH moments) using synthetic annual flood series with varying characteristics and lengths. As the hydrologic events in nature such as daily discharge occur with finite values, their annual maximums are expected to follow the asymptotic form of the limited GEV distribution. Synthetic annual flood series were thus obtained from the stochastic sequences of 365 daily discharges generated by Monte Carlo simulation on the basis of limited probability distribution underlying the limited GEV distribution. The results show that parameter estimation by LH moments of this distribution, fitted to annual flood samples of less than 100-year length derived from initial limited distribution, may indicate any form of extreme-value distribution, not just the limited form as expected, and with large uncertainty in fitted parameters. A frequency analysis, on the basis of GEV distribution and LH moments, of annual flood series of lengths varying between 13 and 73 years observed at 88 gauge stations on Parana River in Brazil, indicated all the three forms of GEV distribution.(Author)

Measuring the Economic Value of Pre-MBA Work Experience

Science.gov (United States)

Yeaple, Ronald N.; Johnston, Mark W.; Whittingham, Keith L.

2010-01-01

Pre-MBA work experience is required for admission to many graduate schools of business. In the present study, MBA graduates with a wide range of pre-MBA work experience were surveyed to assess the economic value of such work experience. No evidence was found of a systematic financial advantage to students from working for several years before…

Penalized Nonlinear Least Squares Estimation of Time-Varying Parameters in Ordinary Differential Equations

KAUST Repository

Cao, Jiguo; Huang, Jianhua Z.; Wu, Hulin

2012-01-01

Ordinary differential equations (ODEs) are widely used in biomedical research and other scientific areas to model complex dynamic systems. It is an important statistical problem to estimate parameters in ODEs from noisy observations. In this article we propose a method for estimating the time-varying coefficients in an ODE. Our method is a variation of the nonlinear least squares where penalized splines are used to model the functional parameters and the ODE solutions are approximated also using splines. We resort to the implicit function theorem to deal with the nonlinear least squares objective function that is only defined implicitly. The proposed penalized nonlinear least squares method is applied to estimate a HIV dynamic model from a real dataset. Monte Carlo simulations show that the new method can provide much more accurate estimates of functional parameters than the existing two-step local polynomial method which relies on estimation of the derivatives of the state function. Supplemental materials for the article are available online.

Family-based Association Analyses of Imputed Genotypes Reveal Genome-Wide Significant Association of Alzheimer’s disease with OSBPL6, PTPRG and PDCL3

Science.gov (United States)

Herold, Christine; Hooli, Basavaraj V.; Mullin, Kristina; Liu, Tian; Roehr, Johannes T; Mattheisen, Manuel; Parrado, Antonio R.; Bertram, Lars; Lange, Christoph; Tanzi, Rudolph E.

2015-01-01

The genetic basis of Alzheimer's disease (AD) is complex and heterogeneous. Over 200 highly penetrant pathogenic variants in the genes APP, PSEN1 and PSEN2 cause a subset of early-onset familial Alzheimer's disease (EOFAD). On the other hand, susceptibility to late-onset forms of AD (LOAD) is indisputably associated to the ε4 allele in the gene APOE, and more recently to variants in more than two-dozen additional genes identified in the large-scale genome-wide association studies (GWAS) and meta-analyses reports. Taken together however, although the heritability in AD is estimated to be as high as 80%, a large proportion of the underlying genetic factors still remain to be elucidated. In this study we performed a systematic family-based genome-wide association and meta-analysis on close to 15 million imputed variants from three large collections of AD families (~3,500 subjects from 1,070 families). Using a multivariate phenotype combining affection status and onset age, meta-analysis of the association results revealed three single nucleotide polymorphisms (SNPs) that achieved genome-wide significance for association with AD risk: rs7609954 in the gene PTPRG (P-value = 3.98·10−08), rs1347297 in the gene OSBPL6 (P-value = 4.53·10−08), and rs1513625 near PDCL3 (P-value = 4.28·10−08). In addition, rs72953347 in OSBPL6 (P-value = 6.36·10−07) and two SNPs in the gene CDKAL1 showed marginally significant association with LOAD (rs10456232, P-value: 4.76·10−07; rs62400067, P-value: 3.54·10−07). In summary, family-based GWAS meta-analysis of imputed SNPs revealed novel genomic variants in (or near) PTPRG, OSBPL6, and PDCL3 that influence risk for AD with genome-wide significance. PMID:26830138

A Genome Wide Association Study Links Glutamate Receptor Pathway to Sporadic Creutzfeldt-Jakob Disease Risk

Science.gov (United States)

Sanchez-Juan, Pascual; Bishop, Matthew T.; Kovacs, Gabor G.; Calero, Miguel; Aulchenko, Yurii S.; Ladogana, Anna; Boyd, Alison; Lewis, Victoria; Ponto, Claudia; Calero, Olga; Poleggi, Anna; Carracedo, Ángel; van der Lee, Sven J.; Ströbel, Thomas; Rivadeneira, Fernando; Hofman, Albert; Haïk, Stéphane; Combarros, Onofre; Berciano, José; Uitterlinden, Andre G.; Collins, Steven J.; Budka, Herbert; Brandel, Jean-Philippe; Laplanche, Jean Louis; Pocchiari, Maurizio; Zerr, Inga; Knight, Richard S. G.; Will, Robert G.; van Duijn, Cornelia M.

2015-01-01

We performed a genome-wide association (GWA) study in 434 sporadic Creutzfeldt-Jakob disease (sCJD) patients and 1939 controls from the United Kingdom, Germany and The Netherlands. The findings were replicated in an independent sample of 1109 sCJD and 2264 controls provided by a multinational consortium. From the initial GWA analysis we selected 23 SNPs for further genotyping in 1109 sCJD cases from seven different countries. Five SNPs were significantly associated with sCJD after correction for multiple testing. Subsequently these five SNPs were genotyped in 2264 controls. The pooled analysis, including 1543 sCJD cases and 4203 controls, yielded two genome wide significant results: rs6107516 (p-value=7.62x10-9) a variant tagging the prion protein gene (PRNP); and rs6951643 (p-value=1.66x10-8) tagging the Glutamate Receptor Metabotropic 8 gene (GRM8). Next we analysed the data stratifying by country of origin combining samples from the pooled analysis with genotypes from the 1000 Genomes Project and imputed genotypes from the Rotterdam Study (Total n=12967). The meta-analysis of the results showed that rs6107516 (p-value=3.00x10-8) and rs6951643 (p-value=3.91x10-5) remained as the two most significantly associated SNPs. Rs6951643 is located in an intronic region of GRM8, a gene that was additionally tagged by a cluster of 12 SNPs within our top100 ranked results. GRM8 encodes for mGluR8, a protein which belongs to the metabotropic glutamate receptor family, recently shown to be involved in the transduction of cellular signals triggered by the prion protein. Pathway enrichment analyses performed with both Ingenuity Pathway Analysis and ALIGATOR postulates glutamate receptor signalling as one of the main pathways associated with sCJD. In summary, we have detected GRM8 as a novel, non-PRNP, genome-wide significant marker associated with heightened disease risk, providing additional evidence supporting a role of glutamate receptors in sCJD pathogenesis. PMID:25918841

Multivariate time-varying volatility modeling using probabilistic fuzzy systems

NARCIS (Netherlands)

Basturk, N.; Almeida, R.J.; Golan, R.; Kaymak, U.

2016-01-01

Methods to accurately analyze financial risk have drawn considerable attention in financial institutions. One difficulty in financial risk analysis is the fact that banks and other financial institutions invest in several assets which show time-varying volatilities and hence time-varying financial

Unit 148 - World Wide Web Basics

OpenAIRE

148, CC in GIScience; Yeung, Albert K.

2000-01-01

This unit explains the characteristics and the working principles of the World Wide Web as the most important protocol of the Internet. Topics covered in this unit include characteristics of the World Wide Web; using the World Wide Web for the dissemination of information on the Internet; and using the World Wide Web for the retrieval of information from the Internet.

Historical Medical Value of Donguibogam

Directory of Open Access Journals (Sweden)

Bong-Keun Song

2016-03-01

Full Text Available Oriental medicine, since its origin in China, has had a long history extending over 2000 years. Today, it comprises several types of medicine predominately practiced in East Asia, including traditional Chinese, traditional Korean, and Kampo medicine. The distinctive medical system of traditional Korean medicine was established shortly after the publication of Donguibogam by Dr. Heo Jun in 1613. Donguibogam is highly acclaimed across East Asia; in 2009, in light of its historical medical value, the United Nations Educational, Scientific, and Cultural Organization registered the book on its cultural heritage list. Here, we review the historical medical value of Donguibogam. The findings confirm that Donguibogam developed a unique and independent form of traditional Korean medicine and innovatively reformed the disease classification system. Moreover, Donguibogam emphasized the importance of disease prevention and medical pragmatism. This book also accelerated the development of folk medicine. Owing to its historical medical value, Donguibogam is now considered the 'bible' of Oriental medicine. Its wide acceptance has contributed to the expansion of Korean medicine utilization among the general public. Donguibogam has also played an important role in the establishment of traditional Korean medicine as a universally valid and original form of medicine, independent of traditional Chinese medicine.

World Wide Web voted most wonderful wonder by web-wide world

CERN Multimedia

2007-01-01

The results are in, and the winner is...the World Wide Web! An online survey conducted by the CNN news group ranks the World Wide Web-invented at CERN--as the most wonderful of the seven modern wonders of the world. (See Bulletin No. 49/2006.) There is currently no speculation about whether they would have had the same results had they distributed the survey by post. The World Wide Web won with a whopping 50 per cent of the votes (3,665 votes). The runner up was CERN again, with 16 per cent of voters (1130 votes) casting the ballot in favour of the CERN particle accelerator. Stepping into place behind CERN and CERN is 'None of the Above' with 8 per cent of the votes (611 votes), followed by the development of Dubai (7%), the bionic arm (7%), China's Three Gorges Damn (5%), The Channel Tunnel (4%), and France's Millau viaduct (3%). Thanks to everyone from CERN who voted. You can view the results on http://edition.cnn.com/SPECIALS/2006/modern.wonders/

A parameterization of momentum roughness length and displacement height for a wide range of canopy densities

Directory of Open Access Journals (Sweden)

A. Verhoef

1997-01-01

Full Text Available Values of the momentum roughness length, z0, and displacement height, d, derived from wind profiles and momentum flux measurements, are selected from the literature for a variety of sparse canopies. These include savannah, tiger-bush and several row crops. A quality assessment of these data, conducted using criteria such as available fetch, height of wind speed measurement and homogeneity of the experimental site, reduced the initial total of fourteen sites to eight. These datapoints, combined with values carried forward from earlier studies on the parameterization of z0 and d, led to a maximum number of 16 and 24 datapoints available for d and z0, respectively. The data are compared with estimates of roughness length and displacement height as predicted from a detailed drag partition model, R92 (Raupach, 1992, and a simplified version of this model, R94 (Raupach, 1994. A key parameter in these models is the roughness density or frontal area index, λ. Both the comprehensive and the simplified model give accurate predictions of measured z0 and d values, but the optimal model coefficients are significantly different from the ones originally proposed in R92 and R94. The original model coefficients are based predominantly on measured aerodynamic parameters of relatively closed canopies and they were fitted `by eye'. In this paper, best-fit coefficients are found from a least squares minimization using the z0 and d values of selected good-quality data for sparse canopies and for the added, mainly closed canopies. According to a statistical analysis, based on the coefficient of determination (r2, the number of observations and the number of fitted model coefficients, the simplified model, R94, is deemed to be the most appropriate for future z0 and d predictions. A CR value of 0.35 and a cd1 value of about 20 are found to be appropriate for a large range of canopies varying in density from closed to very sparse. In this case, 99% of the total variance

Significant or Not : What Does the "Magic" P-Value Tell Us?

OpenAIRE

Nelson, Mary

2016-01-01

The use of the p-value in determination of statistical significance—and by extension in decision making—is widely taught and frequently used.  It is not, however, without limitations, and its use as a primary marker of a worthwhile conclusion has recently come under increased scrutiny.  This paper attempts to explain some lesser-known properties of the p-value, including its distribution under the null and alternative hypotheses, and to clearly present its limitations and some straightforward...

Modern approaches to forming value orientations of junior pupils nowadays

Directory of Open Access Journals (Sweden)

Liudmyla Matsuk

2017-04-01

Full Text Available A number of approaches to the formation of value orientations of primary school children today is outlined in the article. One of the most important tasks of the school in terms of national revival of Ukraine appears education of harmonious, spiritually rich and nationally conscious personality. Educating of the current generation needs serious updating of educational content, development of a wide spectrum of problems associated with the formation of ideological orientations of a personality, development and activity, independence, consciousness, self-consciousness. The solution of the abovementioned problem is possible subject to optimize management of process education through the humanization of education that will ensure the establishment of priority of human values in society.Key words: values, value orientations, training and education, junior pupils, patriotism, identity, dignity, courage, duty, responsibility, tolerance.

The role of utility value in achievement behavior: the importance of culture.

Science.gov (United States)

Shechter, Olga G; Durik, Amanda M; Miyamoto, Yuri; Harackiewicz, Judith M

2011-03-01

Two studies tested how participants' responses to utility value interventions and subsequent interest in a math technique vary by culture (Westerners vs. East Asians) and levels of initial math interest. Participants in Study 1 were provided with information about the utility value of the technique or not. The manipulation was particularly effective for East Asian learners with initially lower math interest, who showed more interest in the technique relative to low-interest Westerners. Study 2 compared the effects of two types of utility value (proximal or distal) and examined the effects on interest, effort, performance, and process variables. Whereas East Asian participants reaped the most motivational benefits from a distal value manipulation, Westerners benefited the most from a proximal value manipulation. These findings have implications for how to promote motivation for learners with different cultural backgrounds and interests.

Effect of TiOx compact layer with varied components on the performance of dye-sensitized solar cells

Energy Technology Data Exchange (ETDEWEB)

Fang, Yanling; Ai, Xianglong; Wang, Xiaomeng; Wang, Qi; Huang, Jianguo; Wu, Tao, E-mail: tao_wu@zju.edu.cn

2014-05-01

Graphical abstract: - Highlights: • TiOx compact layers with varied components are deposited by sputtering deposition. • TiOx compact layers suppressed the recombination at the FTO glass/ electrolyte interface effectively. • 20 nm-TiOx compact layer with the lowest x value (named T1) gave the highest charge transfer or transport and reduced recombination most. • Lower value of x in TiOx showed slightly better transmittance. • Lower value of x in TiOx reveals higher conductivity and better charge transfer from the porous TiO{sub 2} to the substrate. - Abstract: In this study, approximately 20 nm thick compact layers of TiOx with varied components are deposited by physical vapor deposition. The performance of these layers in solar cells is investigated. The TiOx compact layers consist of T1 (with Ti{sup 0}, Ti{sup 2+}, Ti{sup 3+}, and Ti{sup 4+}), T2 (with Ti{sup 3+} and Ti{sup 4+}), and T3 (with Ti{sup 4+}). Results show that the optimum compact layer is T1, which exhibits an approximately 61% enhancement in energy conversion efficiency compared with the bare cell. Mott–Schottky plots indicate that the carrier concentration decreases and the flatband becomes less negative with decreasing x, which consequently increases the likelihood of charge transfer from the nanoporous TiO{sub 2} to the TiOx compact layers. Furthermore, a decrease in the x value of TiOx results in lower resistance. Voltage decay and electrical impedance spectrum (EIS) show that the electron-carrier lifetime and charge recombination reduction are improved the most by T1. Consequently, TiOx with smaller x works better as a compact layer. However, a solar cell with T2 shows weak enhancement of photovoltaic performance. Cyclic voltammetry and EIS illustrate that the low recombination blocking and high resistance of T2 may be a result of its large pore size and weak adhesion to fluorine-doped tin oxide glass.

Values and public acceptability dimensions of sustainable egg production.

Science.gov (United States)

Thompson, P B; Appleby, M; Busch, L; Kalof, L; Miele, M; Norwood, B F; Pajor, E

2011-09-01

The attributes of egg production that elicit values-based responses include the price and availability of eggs, environmental impacts, food safety or health concerns, and animal welfare. Different social groups have distinct interests regarding the sustainability of egg production that reflect these diverse values. Current scientifically based knowledge about how values and attitudes in these groups can be characterized is uneven and must be derived from studies conducted at varying times and using incomplete study methods. In general, some producer and consumer interests are translated through markets and are mediated by market mechanisms, whereas others are poorly reflected by economic behavior. An array of survey and focus group research has been performed to elicit consumer and activist beliefs about performance goals they would expect from an egg production system. These studies provide evidence that consumers' market behavior may be at odds with their ethical and political beliefs about performance goals.

Applicability of the Linear Sorption Isotherm Model to Represent Contaminant Transport Processes in Site Wide Performance Assessments

International Nuclear Information System (INIS)

FOGWELL, T.W.; LAST, G.V.

2003-01-01

The estimation of flux of contaminants through the vadose zone to the groundwater under varying geologic, hydrologic, and chemical conditions is key to making technically credible and sound decisions regarding soil site characterization and remediation, single-shell tank retrieval, and waste site closures (DOE 2000). One of the principal needs identified in the science and technology roadmap (DOE 2000) is the need to improve the conceptual and numerical models that describe the location of contaminants today, and to provide the basis for forecasting future movement of contaminants on both site-specific and site-wide scales. The State of Knowledge (DOE 1999) and Preliminary Concepts documents describe the importance of geochemical processes on the transport of contaminants through the Vadose Zone. These processes have been identified in the international list of Features, Events, and Processes (FEPs) (NEA 2000) and included in the list of FEPS currently being developed for Hanford Site assessments (Soler et al. 2001). The current vision for Hanford site-wide cumulative risk assessments as performed using the System Assessment Capability (SAC) is to represent contaminant adsorption using the linear isotherm (empirical distribution coefficient, K d ) sorption model. Integration Project Expert Panel (PEP) comments indicate that work is required to adequately justify the applicability of the linear sorption model, and to identify and defend the range of K d values that are adopted for assessments. The work plans developed for the Science and Technology (S and T) efforts, SAC, and the Core Projects must answer directly the question of ''Is there a scientific basis for the application of the linear sorption isotherm model to the complex wastes of the Hanford Site?'' This paper is intended to address these issues. The reason that well documented justification is required for using the linear sorption (K d ) model is that this approach is strictly empirical and is often

Novel Miscanthus Germplasm-Based Value Chains: A Life Cycle Assessment

Directory of Open Access Journals (Sweden)

Moritz Wagner

2017-06-01

Full Text Available In recent years, considerable progress has been made in miscanthus research: improvement of management practices, breeding of new genotypes, especially for marginal conditions, and development of novel utilization options. The purpose of the current study was a holistic analysis of the environmental performance of such novel miscanthus-based value chains. In addition, the relevance of the analyzed environmental impact categories was assessed. A Life Cycle Assessment was conducted to analyse the environmental performance of the miscanthus-based value chains in 18 impact categories. In order to include the substitution of a reference product, a system expansion approach was used. In addition, a normalization step was applied. This allowed the relevance of these impact categories to be evaluated for each utilization pathway. The miscanthus was cultivated on six sites in Europe (Aberystwyth, Adana, Moscow, Potash, Stuttgart and Wageningen and the biomass was utilized in the following six pathways: (1 small-scale combustion (heat—chips; (2 small-scale combustion (heat—pellets; (3 large-scale combustion (CHP—biomass baled for transport and storage; (4 large-scale combustion (CHP—pellets; (5 medium-scale biogas plant—ensiled miscanthus biomass; and (6 large-scale production of insulation material. Thus, in total, the environmental performance of 36 site × pathway combinations was assessed. The comparatively high normalized results of human toxicity, marine, and freshwater ecotoxicity, and freshwater eutrophication indicate the relevance of these impact categories in the assessment of miscanthus-based value chains. Differences between the six sites can almost entirely be attributed to variations in biomass yield. However, the environmental performance of the utilization pathways analyzed varied widely. The largest differences were shown for freshwater and marine ecotoxicity, and freshwater eutrophication. The production of insulation material

Extreme values, regular variation and point processes

CERN Document Server

Resnick, Sidney I

1987-01-01

Extremes Values, Regular Variation and Point Processes is a readable and efficient account of the fundamental mathematical and stochastic process techniques needed to study the behavior of extreme values of phenomena based on independent and identically distributed random variables and vectors It presents a coherent treatment of the distributional and sample path fundamental properties of extremes and records It emphasizes the core primacy of three topics necessary for understanding extremes the analytical theory of regularly varying functions; the probabilistic theory of point processes and random measures; and the link to asymptotic distribution approximations provided by the theory of weak convergence of probability measures in metric spaces The book is self-contained and requires an introductory measure-theoretic course in probability as a prerequisite Almost all sections have an extensive list of exercises which extend developments in the text, offer alternate approaches, test mastery and provide for enj...

Genetic polymorphisms in varied environments.

Science.gov (United States)

Powell, J R

1971-12-03

Thirteen experimenital populationis of Drosophila willistoni were maintained in cages, in some of which the environments were relatively constant and in others varied. After 45 weeks, the populations were assayed by gel electrophoresis for polymorphisms at 22 protein loci. The average heterozygosity per individual and the average unmber of alleles per locus were higher in populations maintained in heterogeneous environments than in populations in more constant enviroments.

Wide spectral band beam analysis

Science.gov (United States)

Aharon, Oren

2015-03-01

The reality in laser beam profiling is that measurements are performed over a wide spectrum of wavelengths and power ranges. Many applications use multiple laser wavelengths with very different power levels, a fact which dictates a need for a better measuring tool. Rapid progress in the fiber laser area has increased the demand for lasers in the wavelength range of 900 - 1030 nm, while the telecommunication market has increased the demand for wavelength range of 1300nm - 1600 nm, on the other hand the silicone chip manufacturing and mass production requirements tend to lower the laser wavelength towards the 190nm region. In many cases there is a need to combine several lasers together in order to perform a specific task. A typical application is to combine one visible laser for pointing, with a different laser for material processing with a very different wavelength and power level. The visible laser enables accurate pointing before the second laser is operated. The beam profile of the intensity distribution is an important parameter that indicates how a laser beam will behave in an application. Currently a lab, where many different lasers are used, will find itself using various laser beam profilers from several vendors with different specifications and accuracies. It is the propose of this article to present a technological breakthrough in the area of detectors, electronics and optics allowing intricate measurements of lasers with different wavelength and with power levels that vary many orders of magnitude by a single beam profiler.

Pemodelan Markov Switching Dengan Time-varying Transition Probability

OpenAIRE

Savitri, Anggita Puri; Warsito, Budi; Rahmawati, Rita

2016-01-01

Exchange rate or currency is an economic variable which reflects country's state of economy. It fluctuates over time because of its ability to switch the condition or regime caused by economic and political factors. The changes in the exchange rate are depreciation and appreciation. Therefore, it could be modeled using Markov Switching with Time-Varying Transition Probability which observe the conditional changes and use information variable. From this model, time-varying transition probabili...

Image Denoising Using Singular Value Difference in the Wavelet Domain

Directory of Open Access Journals (Sweden)

Min Wang

2018-01-01

Full Text Available Singular value (SV difference is the difference in the singular values between a noisy image and the original image; it varies regularly with noise intensity. This paper proposes an image denoising method using the singular value difference in the wavelet domain. First, the SV difference model is generated for different noise variances in the three directions of the wavelet transform and the noise variance of a new image is used to make the calculation by the diagonal part. Next, the single-level discrete 2-D wavelet transform is used to decompose each noisy image into its low-frequency and high-frequency parts. Then, singular value decomposition (SVD is used to obtain the SVs of the three high-frequency parts. Finally, the three denoised high-frequency parts are reconstructed by SVD from the SV difference, and the final denoised image is obtained using the inverse wavelet transform. Experiments show the effectiveness of this method compared with relevant existing methods.

Estimating the option value of a non-firm electricity tariff

International Nuclear Information System (INIS)

Moore, J.; Horii, B.; Price, S.; Olson, A.; Woo, C.K.

2010-01-01

We estimate the option value of a non-firm electricity tariff commonly used by a local distribution company (LDC) in its electricity demand response program. This option value captures the benefit that a LDC enjoys from not serving an end-use load during high-price hours in a wholesale electricity market. It is conservative in that it does not include the cost savings in meeting the LDC's resource adequacy requirement or deferring transmission and distribution (T and D) investments necessary for delivering reliable service. Illustrated by a Northern California example, our two-pronged approach entails (a) a set of summer monthly market price regressions to forecast daily spot price distributions that incorporate uncertainty in natural gas price and weather; and (b) a simulation exercise to quantify the tariff's value under a specific design. The results indicate that a non-firm service tariff can have varying option value estimates that are highly sensitive to the tariff's design, and that an incentive payment based on the option value alone is likely insufficient to attract customer participation in a non-firm service program. (author)

Genome-wide scan of healthy human connectome discovers SPON1 gene variant influencing dementia severity

Science.gov (United States)

Jahanshad, Neda; Rajagopalan, Priya; Hua, Xue; Hibar, Derrek P.; Nir, Talia M.; Toga, Arthur W.; Jack, Clifford R.; Saykin, Andrew J.; Green, Robert C.; Weiner, Michael W.; Medland, Sarah E.; Montgomery, Grant W.; Hansell, Narelle K.; McMahon, Katie L.; de Zubicaray, Greig I.; Martin, Nicholas G.; Wright, Margaret J.; Thompson, Paul M.; Weiner, Michael; Aisen, Paul; Weiner, Michael; Aisen, Paul; Petersen, Ronald; Jack, Clifford R.; Jagust, William; Trojanowski, John Q.; Toga, Arthur W.; Beckett, Laurel; Green, Robert C.; Saykin, Andrew J.; Morris, John; Liu, Enchi; Green, Robert C.; Montine, Tom; Petersen, Ronald; Aisen, Paul; Gamst, Anthony; Thomas, Ronald G.; Donohue, Michael; Walter, Sarah; Gessert, Devon; Sather, Tamie; Beckett, Laurel; Harvey, Danielle; Gamst, Anthony; Donohue, Michael; Kornak, John; Jack, Clifford R.; Dale, Anders; Bernstein, Matthew; Felmlee, Joel; Fox, Nick; Thompson, Paul; Schuff, Norbert; Alexander, Gene; DeCarli, Charles; Jagust, William; Bandy, Dan; Koeppe, Robert A.; Foster, Norm; Reiman, Eric M.; Chen, Kewei; Mathis, Chet; Morris, John; Cairns, Nigel J.; Taylor-Reinwald, Lisa; Trojanowki, J.Q.; Shaw, Les; Lee, Virginia M.Y.; Korecka, Magdalena; Toga, Arthur W.; Crawford, Karen; Neu, Scott; Saykin, Andrew J.; Foroud, Tatiana M.; Potkin, Steven; Shen, Li; Khachaturian, Zaven; Frank, Richard; Snyder, Peter J.; Molchan, Susan; Kaye, Jeffrey; Quinn, Joseph; Lind, Betty; Dolen, Sara; Schneider, Lon S.; Pawluczyk, Sonia; Spann, Bryan M.; Brewer, James; Vanderswag, Helen; Heidebrink, Judith L.; Lord, Joanne L.; Petersen, Ronald; Johnson, Kris; Doody, Rachelle S.; Villanueva-Meyer, Javier; Chowdhury, Munir; Stern, Yaakov; Honig, Lawrence S.; Bell, Karen L.; Morris, John C.; Ances, Beau; Carroll, Maria; Leon, Sue; Mintun, Mark A.; Schneider, Stacy; Marson, Daniel; Griffith, Randall; Clark, David; Grossman, Hillel; Mitsis, Effie; Romirowsky, Aliza; deToledo-Morrell, Leyla; Shah, Raj C.; Duara, Ranjan; Varon, Daniel; Roberts, Peggy; Albert, Marilyn; Onyike, Chiadi; Kielb, Stephanie; Rusinek, Henry; de Leon, Mony J.; Glodzik, Lidia; De Santi, Susan; Doraiswamy, P. Murali; Petrella, Jeffrey R.; Coleman, R. Edward; Arnold, Steven E.; Karlawish, Jason H.; Wolk, David; Smith, Charles D.; Jicha, Greg; Hardy, Peter; Lopez, Oscar L.; Oakley, MaryAnn; Simpson, Donna M.; Porsteinsson, Anton P.; Goldstein, Bonnie S.; Martin, Kim; Makino, Kelly M.; Ismail, M. Saleem; Brand, Connie; Mulnard, Ruth A.; Thai, Gaby; Mc-Adams-Ortiz, Catherine; Womack, Kyle; Mathews, Dana; Quiceno, Mary; Diaz-Arrastia, Ramon; King, Richard; Weiner, Myron; Martin-Cook, Kristen; DeVous, Michael; Levey, Allan I.; Lah, James J.; Cellar, Janet S.; Burns, Jeffrey M.; Anderson, Heather S.; Swerdlow, Russell H.; Apostolova, Liana; Lu, Po H.; Bartzokis, George; Silverman, Daniel H.S.; Graff-Radford, Neill R.; Parfitt, Francine; Johnson, Heather; Farlow, Martin R.; Hake, Ann Marie; Matthews, Brandy R.; Herring, Scott; van Dyck, Christopher H.; Carson, Richard E.; MacAvoy, Martha G.; Chertkow, Howard; Bergman, Howard; Hosein, Chris; Black, Sandra; Stefanovic, Bojana; Caldwell, Curtis; Hsiung, Ging-Yuek Robin; Feldman, Howard; Mudge, Benita; Assaly, Michele; Kertesz, Andrew; Rogers, John; Trost, Dick; Bernick, Charles; Munic, Donna; Kerwin, Diana; Mesulam, Marek-Marsel; Lipowski, Kristina; Wu, Chuang-Kuo; Johnson, Nancy; Sadowsky, Carl; Martinez, Walter; Villena, Teresa; Turner, Raymond Scott; Johnson, Kathleen; Reynolds, Brigid; Sperling, Reisa A.; Johnson, Keith A.; Marshall, Gad; Frey, Meghan; Yesavage, Jerome; Taylor, Joy L.; Lane, Barton; Rosen, Allyson; Tinklenberg, Jared; Sabbagh, Marwan; Belden, Christine; Jacobson, Sandra; Kowall, Neil; Killiany, Ronald; Budson, Andrew E.; Norbash, Alexander; Johnson, Patricia Lynn; Obisesan, Thomas O.; Wolday, Saba; Bwayo, Salome K.; Lerner, Alan; Hudson, Leon; Ogrocki, Paula; Fletcher, Evan; Carmichael, Owen; Olichney, John; DeCarli, Charles; Kittur, Smita; Borrie, Michael; Lee, T.-Y.; Bartha, Rob; Johnson, Sterling; Asthana, Sanjay; Carlsson, Cynthia M.; Potkin, Steven G.; Preda, Adrian; Nguyen, Dana; Tariot, Pierre; Fleisher, Adam; Reeder, Stephanie; Bates, Vernice; Capote, Horacio; Rainka, Michelle; Scharre, Douglas W.; Kataki, Maria; Zimmerman, Earl A.; Celmins, Dzintra; Brown, Alice D.; Pearlson, Godfrey D.; Blank, Karen; Anderson, Karen; Saykin, Andrew J.; Santulli, Robert B.; Schwartz, Eben S.; Sink, Kaycee M.; Williamson, Jeff D.; Garg, Pradeep; Watkins, Franklin; Ott, Brian R.; Querfurth, Henry; Tremont, Geoffrey; Salloway, Stephen; Malloy, Paul; Correia, Stephen; Rosen, Howard J.; Miller, Bruce L.; Mintzer, Jacobo; Longmire, Crystal Flynn; Spicer, Kenneth; Finger, Elizabeth; Rachinsky, Irina; Rogers, John; Kertesz, Andrew; Drost, Dick

2013-01-01

Aberrant connectivity is implicated in many neurological and psychiatric disorders, including Alzheimer’s disease and schizophrenia. However, other than a few disease-associated candidate genes, we know little about the degree to which genetics play a role in the brain networks; we know even less about specific genes that influence brain connections. Twin and family-based studies can generate estimates of overall genetic influences on a trait, but genome-wide association scans (GWASs) can screen the genome for specific variants influencing the brain or risk for disease. To identify the heritability of various brain connections, we scanned healthy young adult twins with high-field, high-angular resolution diffusion MRI. We adapted GWASs to screen the brain’s connectivity pattern, allowing us to discover genetic variants that affect the human brain’s wiring. The association of connectivity with the SPON1 variant at rs2618516 on chromosome 11 (11p15.2) reached connectome-wide, genome-wide significance after stringent statistical corrections were enforced, and it was replicated in an independent subsample. rs2618516 was shown to affect brain structure in an elderly population with varying degrees of dementia. Older people who carried the connectivity variant had significantly milder clinical dementia scores and lower risk of Alzheimer’s disease. As a posthoc analysis, we conducted GWASs on several organizational and topological network measures derived from the matrices to discover variants in and around genes associated with autism (MACROD2), development (NEDD4), and mental retardation (UBE2A) significantly associated with connectivity. Connectome-wide, genome-wide screening offers substantial promise to discover genes affecting brain connectivity and risk for brain diseases. PMID:23471985

Observer-based linear parameter varying H∞ tracking control for hypersonic vehicles

Directory of Open Access Journals (Sweden)

Yiqing Huang

2016-11-01

Full Text Available This article aims to develop observer-based linear parameter varying output feedback H∞ tracking controller for hypersonic vehicles. Due to the complexity of an original nonlinear model of the hypersonic vehicle dynamics, a slow–fast loop linear parameter varying polytopic model is introduced for system stability analysis and controller design. Then, a state observer is developed by linear parameter varying technique in order to estimate the unmeasured attitude angular for slow loop system. Also, based on the designed linear parameter varying state observer, a kind of attitude tracking controller is presented to reduce tracking errors for all bounded reference attitude angular inputs. The closed-loop linear parameter varying system is proved to be quadratically stable by Lypapunov function technique. Finally, simulation results show that the developed linear parameter varying H∞ controller has good tracking capability for reference commands.

Genomic research and wide data sharing: views of prospective participants.

Science.gov (United States)

Trinidad, Susan Brown; Fullerton, Stephanie M; Bares, Julie M; Jarvik, Gail P; Larson, Eric B; Burke, Wylie

2010-08-01

Sharing study data within the research community generates tension between two important goods: promoting scientific goals and protecting the privacy interests of study participants. This study was designed to explore the perceptions, beliefs, and attitudes of research participants and possible future participants regarding genome-wide association studies and repository-based research. Focus group sessions with (1) current research participants, (2) surrogate decision-makers, and (3) three age-defined cohorts (18-34 years, 35-50, >50). Participants expressed a variety of opinions about the acceptability of wide sharing of genetic and phenotypic information for research purposes through large, publicly accessible data repositories. Most believed that making de-identified study data available to the research community is a social good that should be pursued. Privacy and confidentiality concerns were common, although they would not necessarily preclude participation. Many participants voiced reservations about sharing data with for-profit organizations. Trust is central in participants' views regarding data sharing. Further research is needed to develop governance models that enact the values of stewardship.

Area-wide integrated pest management and the sterile insect technique

International Nuclear Information System (INIS)

Klassen, W.

2005-01-01

Area-wide integrated pest management (AW-IPM) focuses on the preventive management of pest populations throughout the ecosystem. It seeks to treat all habitats of the pest population so that none produces migrants to re-establish significant infestations in areas of concern. In contrast, the conventional strategy focuses narrowly on defending the valued entity (crop, livestock, people, buildings, etc.) from direct attack by pests. AW-IPM requires multiyear planning, and an organization dedicated exclusively to its implementation, whereas conventional pest management involves minimal forward planning, tends to be reactive, and is implemented independently by individual producers, businesses, or households. AW-IPM tends to utilize advanced technologies, whereas the conventional strategy tends to rely on traditional tactics and tools. The sterile insect technique (SIT) is a species-specific form of birth control imposed on the pest population. It is a powerful tool for 'mopping up' sparse pest populations, and is most efficient when applied as a tactic in a system deployed on an area-wide basis. On environmental, economic and biological grounds, the case for the SIT is compelling. (author)

Robust stability analysis of switched Hopfield neural networks with time-varying delay under uncertainty

International Nuclear Information System (INIS)

Huang He; Qu Yuzhong; Li Hanxiong

2005-01-01

With the development of intelligent control, switched systems have been widely studied. Here we try to introduce some ideas of the switched systems into the field of neural networks. In this Letter, a class of switched Hopfield neural networks with time-varying delay is investigated. The parametric uncertainty is considered and assumed to be norm bounded. Firstly, the mathematical model of the switched Hopfield neural networks is established in which a set of Hopfield neural networks are used as the individual subsystems and an arbitrary switching rule is assumed; Secondly, robust stability analysis for such switched Hopfield neural networks is addressed based on the Lyapunov-Krasovskii approach. Some criteria are given to guarantee the switched Hopfield neural networks to be globally exponentially stable for all admissible parametric uncertainties. These conditions are expressed in terms of some strict linear matrix inequalities (LMIs). Finally, a numerical example is provided to illustrate our results

Unique cultural values of Madura cattle: is cross-breeding a threat?

NARCIS (Netherlands)

Tri Satya Mastuti Widi, Tri; Udo, H.M.J.; Oldenbroek, J.K.; Budisatria, I.G.S.; Baliarti, E.; Zijpp, van der A.J.

2013-01-01

In Indonesia, cross-breeding local cattle with European beef breeds is widely promoted to stimulate beef production. This cross-breeding is threatening local breeds that have often different functions, including cultural roles. This study analysed the cultural values of Madura cattle and the effects

Computation of covex bounds for present value functions with random payments

NARCIS (Netherlands)

Ahcan, A.; Darkiewicz, G.; Goovaerts, M.J.; Hoedemakers, T.

2006-01-01

In this contribution we study the distribution of the present value function of a series of random payments in a stochastic financial environment. Such distributions occur naturally in a wide range of applications within fields of insurance and finance. We obtain accurate approximations by

Estrelas variáveis

OpenAIRE

Viana, Sérgio Manuel de Oliveira

2001-01-01

A observação do céu nocturno é uma prática que vem da Antiguidade. Desde então e durante muito tempo pensou-se que as estrelas mantinham o brilho constante. Assim foi até ao século XVI, quando David Fabricius observou uma estrela cujo brilho variava periodicamente. Dois séculos mais tarde, Jonh Goodricke descobriu uma segunda estrela e com o desenvolvimento de instrumentos de observação este conjunto foi muito alargado e hoje inclui o Sol.A variação do brilho das estrelas variáveis permite d...

The varying cosmological constant: a new approximation to the Friedmann equations and universe model

Science.gov (United States)

Öztaş, Ahmet M.; Dil, Emre; Smith, Michael L.

2018-05-01

We investigate the time-dependent nature of the cosmological constant, Λ, of the Einstein Field Equation (EFE). Beginning with the Einstein-Hilbert action as our fundamental principle we develop a modified version of the EFE allowing the value of Λ to vary as a function of time, Λ(t), indirectly, for an expanding universe. We follow the evolving Λ presuming four-dimensional space-time and a flat universe geometry and present derivations of Λ(t) as functions of the Hubble constant, matter density, and volume changes which can be traced back to the radiation epoch. The models are more detailed descriptions of the Λ dependence on cosmological factors than previous, allowing calculations of the important parameters, Ωm and Ωr, to deep lookback times. Since we derive these without the need for extra dimensions or other special conditions our derivations are useful for model evaluation with astronomical data. This should aid resolution of several difficult problems of astronomy such as the best value for the Hubble constant at present and at recombination.

Fires in Seasonally Dry Tropical Forest: Testing the Varying Constraints Hypothesis across a Regional Rainfall Gradient.

Science.gov (United States)

Mondal, Nandita; Sukumar, Raman

2016-01-01

The "varying constraints hypothesis" of fire in natural ecosystems postulates that the extent of fire in an ecosystem would differ according to the relative contribution of fuel load and fuel moisture available, factors that vary globally along a spatial gradient of climatic conditions. We examined if the globally widespread seasonally dry tropical forests (SDTFs) can be placed as a single entity in this framework by analyzing environmental influences on fire extent in a structurally diverse SDTF landscape in the Western Ghats of southern India, representative of similar forests in monsoonal south and southeast Asia. We used logistic regression to model fire extent with factors that represent fuel load and fuel moisture at two levels-the overall landscape and within four defined moisture regimes (between 700 and1700 mm yr-1)-using a dataset of area burnt and seasonal rainfall from 1990 to 2010. The landscape scale model showed that the extent of fire in a given year within this SDTF is dependent on the combined interaction of seasonal rainfall and extent burnt the previous year. Within individual moisture regimes the relative contribution of these factors to the annual extent burnt varied-early dry season rainfall (i.e., fuel moisture) was the predominant factor in the wettest regime, while wet season rainfall (i.e., fuel load) had a large influence on fire extent in the driest regime. Thus, the diverse structural vegetation types associated with SDTFs across a wide range of rainfall regimes would have to be examined at finer regional or local scales to understand the specific environmental drivers of fire. Our results could be extended to investigating fire-climate relationships in STDFs of monsoonal Asia.

Valuing Manggarai Station – Soekarno-Hatta International Airport Rail Link Using Stated Preference Approach

OpenAIRE

Adi, Wahyu Tamtomo

2015-01-01

This study attempts to identify the characteristics and preference of the SHIA airport travelers, estimate the subjective value of in-vehicle time and waiting time by providing choice experiments regarding the available modes in combination with the Airport Rail Link (ARL) service as hypothetical situation, analyze how the values vary according to the socio-demographics of respondents and forecasting the mode sharing and the elasticity based on several scenarios. Five hundred respondents as p...