Modeling and designing of variable-period and variable-pole-number undulator

Directory of Open Access Journals (Sweden)

I. Davidyuk

2016-02-01

Full Text Available The concept of permanent-magnet variable-period undulator (VPU was proposed several years ago and has found few implementations so far. The VPUs have some advantages as compared with conventional undulators, e.g., a wider range of radiation wavelength tuning and the option to increase the number of poles for shorter periods. Both these advantages will be realized in the VPU under development now at Budker INP. In this paper, we present the results of 2D and 3D magnetic field simulations and discuss some design features of this VPU.

The pulsation mode and period-luminosity relationship of cool variables in globular clusters

International Nuclear Information System (INIS)

Whitelock, P.A.

1986-01-01

The period-luminosity-temperature relationship for globular cluster red and yellow variables is examined. The results suggest that the higher temperature, more metal-deficient cluster variables pulsate in the fundamental mode, while the lower temperature more metal-rich variables pulsate in the first overtone. On the assumption that this is correct, a relationship between fundamental period and bolometric magnitude is derived for cluster variables with observed periods of between 1 and 300 days. (author)

Combination spectra in long-period variable stars

International Nuclear Information System (INIS)

Bruce, C.E.R.

1975-01-01

The electrical discharge theory of the variation in excitation observed in the atmosphere of the long period variable stars offers an explanation for the combination spectra exhibited by many of these stars, which is shown to be in accord with several of the most outstanding changes in their spectra and magnitude. (author)

Theoretical statistics of zero-age cataclysmic variables

International Nuclear Information System (INIS)

Politano, M.J.

1988-01-01

The distribution of the white dwarf masses, the distribution of the mass ratios and the distribution of the orbital periods in cataclysmic variables which are forming at the present time are calculated. These systems are referred to as zero-age cataclysmic variables. The results show that 60% of the systems being formed contain helium white dwarfs and 40% contain carbon-oxygen white dwarfs. The mean dwarf mass in those systems containing helium white dwarfs is 0.34. The mean white dwarf mass in those systems containing carbon-oxygen white dwarfs is 0.75. The orbital period distribution identifies four main classes of zero-age cataclysmic variables: (1) short-period systems containing helium white dwarfs, (2) systems containing carbon-oxygen white dwarfs whose secondaries are convectively stable against rapid mass transfer to the white dwarf, (3) systems containing carbon-oxygen white dwarfs whose secondaries are radiatively stable against rapid mass transfer to the white dwarf and (4) long period systems with evolved secondaries. The white dwarf mass distribution in zero-age cataclysmic variables has direct application to the calculation of the frequency of outburst in classical novae as a function of the mass of the white dwarf. The method developed in this thesis to calculate the distributions of the orbital parameters in zero-age cataclysmic variables can be used to calculate theoretical statistics of any class of binary systems. This method provides a theoretical framework from which to investigate the statistical properties and the evolution of the orbital parameters of binary systems

EXPLORING THE VARIABLE SKY WITH LINEAR. III. CLASSIFICATION OF PERIODIC LIGHT CURVES

Energy Technology Data Exchange (ETDEWEB)

Palaversa, Lovro; Eyer, Laurent; Rimoldini, Lorenzo [Observatoire Astronomique de l' Université de Genève, 51 chemin des Maillettes, CH-1290 Sauverny (Switzerland); Ivezić, Željko; Loebman, Sarah; Hunt-Walker, Nicholas; VanderPlas, Jacob; Westman, David; Becker, Andrew C. [Department of Astronomy, University of Washington, P.O. Box 351580, Seattle, WA 98195-1580 (United States); Ruždjak, Domagoj; Sudar, Davor; Božić, Hrvoje [Hvar Observatory, Faculty of Geodesy, Kačićeva 26, 10000 Zagreb (Croatia); Galin, Mario [Faculty of Geodesy, Kačićeva 26, 10000 Zagreb (Croatia); Kroflin, Andrea; Mesarić, Martina; Munk, Petra; Vrbanec, Dijana [Department of Physics, Faculty of Science, University of Zagreb, Bijenička cesta 32, 10000 Zagreb (Croatia); Sesar, Branimir [Division of Physics, Mathematics, and Astronomy, Caltech, Pasadena, CA 91125 (United States); Stuart, J. Scott [Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, MA 02420-9108 (United States); Srdoč, Gregor, E-mail: lovro.palaversa@unige.ch [Saršoni 90, 51216 Viškovo (Croatia); and others

2013-10-01

We describe the construction of a highly reliable sample of ∼7000 optically faint periodic variable stars with light curves obtained by the asteroid survey LINEAR across 10,000 deg{sup 2} of the northern sky. The majority of these variables have not been cataloged yet. The sample flux limit is several magnitudes fainter than most other wide-angle surveys; the photometric errors range from ∼0.03 mag at r = 15 to ∼0.20 mag at r = 18. Light curves include on average 250 data points, collected over about a decade. Using Sloan Digital Sky Survey (SDSS) based photometric recalibration of the LINEAR data for about 25 million objects, we selected ∼200,000 most probable candidate variables with r < 17 and visually confirmed and classified ∼7000 periodic variables using phased light curves. The reliability and uniformity of visual classification across eight human classifiers was calibrated and tested using a catalog of variable stars from the SDSS Stripe 82 region and verified using an unsupervised machine learning approach. The resulting sample of periodic LINEAR variables is dominated by 3900 RR Lyrae stars and 2700 eclipsing binary stars of all subtypes and includes small fractions of relatively rare populations such as asymptotic giant branch stars and SX Phoenicis stars. We discuss the distribution of these mostly uncataloged variables in various diagrams constructed with optical-to-infrared SDSS, Two Micron All Sky Survey, and Wide-field Infrared Survey Explorer photometry, and with LINEAR light-curve features. We find that the combination of light-curve features and colors enables classification schemes much more powerful than when colors or light curves are each used separately. An interesting side result is a robust and precise quantitative description of a strong correlation between the light-curve period and color/spectral type for close and contact eclipsing binary stars (β Lyrae and W UMa): as the color-based spectral type varies from K4 to F5, the

Methods for the Quasi-Periodic Variability Analysis in Blazars Y. Liu ...

Indian Academy of Sciences (India)

the variability analysis in blazars in optical and radio bands, to search for possible quasi-periodic signals. 2. Power spectral density (PSD). In statistical signal processing and physics, the power spectral density (PSD) is a positive real function of a frequency variable associated with a stationary stochas- tic process. Intuitively ...

Periodicity and stability for variable-time impulsive neural networks.

Science.gov (United States)

Li, Hongfei; Li, Chuandong; Huang, Tingwen

2017-10-01

The paper considers a general neural networks model with variable-time impulses. It is shown that each solution of the system intersects with every discontinuous surface exactly once via several new well-proposed assumptions. Moreover, based on the comparison principle, this paper shows that neural networks with variable-time impulse can be reduced to the corresponding neural network with fixed-time impulses under well-selected conditions. Meanwhile, the fixed-time impulsive systems can be regarded as the comparison system of the variable-time impulsive neural networks. Furthermore, a series of sufficient criteria are derived to ensure the existence and global exponential stability of periodic solution of variable-time impulsive neural networks, and to illustrate the same stability properties between variable-time impulsive neural networks and the fixed-time ones. The new criteria are established by applying Schaefer's fixed point theorem combined with the use of inequality technique. Finally, a numerical example is presented to show the effectiveness of the proposed results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Period--luminosity--color relations and pulsation modes of pulsating variable stars

International Nuclear Information System (INIS)

Breger, M.; Bregman, J.N.

1975-01-01

The periods of delta Scuti, RR Lyrae, dwarf Cepheid, and W Virginis variables have been investigated for their dependence on luminosity, color, mass, and pulsation modes. A maximum-likelihood method, which includes consideration of the observational errors in each coordinate, has been applied to obtain observational period-luminosity-color (P-L-C) relations

Eight to 14 μm spectral monitoring of long period variable stars with GLADYS.

Science.gov (United States)

Levan, P. D.; Sloan, G.; Grasdalen, G.

The authors describe an ongoing program of spectral monitoring of long period variable stars using GLADYS, a long slit prism spectrometer that employs a 58x62 pixel Si:Ga detector array. The goal is to compare the equivalent widths of the SiC emission features in carbon-rich circumstellar shells, and the silicate emission features in oxygen-rich circumstellar stars, obtained over different phases of the continuum variability cycle. Spectra of long period variables and low amplitude variables recently obtained on the Wyoming Infrared Observatory 2.3 m telescope are presented.

Computing Optical Variable Periods of BL Lac Object S5 0716+ 714 ...

Indian Academy of Sciences (India)

Computing Optical Variable Periods of BL Lac Object S5 0716+ 714 ... The study of long-term periodical variation is an important way to get the charac- ... continuous Fourier transform together, define a window function, and finally obtain.

Crop-ecology and nutritional variability influence growth and secondary metabolites of Stevia rebaudiana Bertoni.

Science.gov (United States)

Pal, Probir Kumar; Kumar, Rajender; Guleria, Vipan; Mahajan, Mitali; Prasad, Ramdeen; Pathania, Vijaylata; Gill, Baljinder Singh; Singh, Devinder; Chand, Gopi; Singh, Bikram; Singh, Rakesh Deosharan; Ahuja, Paramvir Singh

2015-02-27

Plant nutrition and climatic conditions play important roles on the growth and secondary metabolites of stevia (Stevia rebaudiana Bertoni); however, the nutritional dose is strongly governed by the soil properties and climatic conditions of the growing region. In northern India, the interactive effects of crop ecology and plant nutrition on yield and secondary metabolites of stevia are not yet properly understood. Thus, a field experiment comprising three levels of nitrogen, two levels of phosphorus and three levels of potassium was conducted at three locations to ascertain whether the spatial and nutritional variability would dominate the leaf yield and secondary metabolites profile of stevia. Principal component analysis (PCA) indicates that the applications of 90 kg N, 40 kg P2O5 and 40 kg K2O ha-1 are the best nutritional conditions in terms of dry leaf yield for CSIR-IHBT (Council of Scientific and Industrial Research- Institute Himalayan Bioresource Technology) and RHRS (Regional Horticultural Research Station) conditions. The spatial variability also exerted considerable effect on the leaf yield and stevioside content in leaves. Among the three locations, CSIR-IHBT was found most suitable in case of dry leaf yield and secondary metabolites accumulation in leaves. The results suggest that dry leaf yield and accumulation of stevioside are controlled by the environmental factors and agronomic management; however, the accumulation of rebaudioside-A (Reb-A) is not much influenced by these two factors. Thus, leaf yield and secondary metabolite profiles of stevia can be improved through the selection of appropriate growing locations and proper nutrient management.

Confirming Variability in the Secondary Eclipse Depth of the Rocky Super-Earth 55 Cancri e

Science.gov (United States)

Tamburo, Patrick; Mandell, Avi; Deming, Drake; Garhart, Emily

2017-01-01

We present a reanalysis of Spitzer transit and secondary eclipse observations of the rocky super Earth 55 Cancri e using Pixel Level Decorrelation (Deming et al. 2015). Secondary eclipses of this planet were found to be significantly variable by Demory et al. (2016), implying a changing brightness temperature which could be evidence of volcanic activity due to tidal forces. If genuine, this result would represent the first evidence for such a process outside of bodies in our own solar system, and would further expand our understanding of the huge variety of planetary systems that can develop in our universe. Spitzer eclipse observations, however, are subject to strong systematic effects which can heavily impact the retrieved eclipse model. A reanalysis of this result with an independent method is therefore needed to confirm eclipse depth variability. We tentatively confirm variability, finding a shallower increase in eclipse depth over the course of observations compared to Demory et al. (2015).

Heart period variability and psychopathology in urban boys at risk for delinquency.

Science.gov (United States)

Pine, D S; Wasserman, G A; Miller, L; Coplan, J D; Bagiella, E; Kovelenku, P; Myers, M M; Sloan, R P

1998-09-01

To examine associations between heart period variability (HPV) and psychopathology in young urban boys at risk for delinquency, a series of 697-11-year-old younger brothers of adjudicated delinquents received a standardized psychiatric evaluation and an assessment of heart period variability (HPV). Psychiatric symptoms were rated in two domains: externalizing and internalizing psychopathology. Continuous measures of both externalizing and internalizing psychopathology were associated with reductions in HPV components related to parasympathetic activity. These associations could not be explained by a number of potentially confounding variables, such as age, ethnicity, social class, body size, or family history of hypertension. Although familial hypertension predicted reduced HPV and externalizing psychopathology, associations between externalizing psychopathology and HPV were independent of familial hypertension. Psychiatric symptoms are associated with reduced HPV in young urban boys at risk for delinquency.

Optimising secondary prevention in the acute period following a TIA of ischaemic origin.

Science.gov (United States)

Heron, Neil

2016-01-01

Transient ischaemic attacks (TIAs) are highly prevalent conditions, with at least 46 000 people per year in the UK having a TIA for the first time. TIAs are a warning that the patient is at risk of further vascular events and the 90-day risk of vascular events following a TIA, excluding events within the first week after diagnosis when the risk is highest, can be as high as 18%. Immediate assessment of patients with TIA, either at accident and emergency, general practice and/or TIA clinics, is therefore required to address secondary prevention and prevent further vascular events. This article addresses the need for optimising secondary prevention in the acute period following a TIA of ischaemic origin to reduce the risk of further vascular events as per recent Cochrane review advice and presents a novel project, Stroke Prevention Rehabilitation Intervention Trial of Exercise (SPRITE), to do this. One novel way to tackle vascular risk factors and promote secondary prevention in patients with TIA could be to adapt a cardiac rehabilitation programme for these patients. SPRITE, a feasibility and pilot study (ClinicalTrials.gov Identifier: NCT02712385) funded by the National Institute for Health Research, is attempting to adapt a home-based cardiac rehabilitation programme, 'The Healthy Brain Rehabilitation Manual', for use in the acute period following a TIA. The use of cardiac rehabilitation programmes post-TIA requires further research, particularly within the primary care setting.

note on variable incubation period within a clutch of eggs

African Journals Online (AJOL)

Compo Biochem. Physiol. 53A: 1-6. MENDELSOHN, 1. M., BIGOS, H. C. & LEDGER, 1. A. In press. The biology of the black-shouldered. NOTE ON VARIABLE. INCUBATION PERIOD WITHIN A. CLUTCH OF EGGS OF THE. LEOPARD TORTOISE. (GEOCHELONE P ARDALIS). (CHELONIA: CRYPTODIRA: TESTUDINIDAE).

Principals' Personal Variables and Information and Communication Technology Utilization in Federal Capital Territory Senior Secondary Schools, Abuja, Nigeria

Science.gov (United States)

Ogunshola, Roseline Folashade; Adeniyi, Abiodun

2017-01-01

The study investigated principals' personal variables and information and communication technology utilization in Federal Capital Territory (FCT) senior secondary schools, Abuja, Nigeria. The study adopted the correlational research design. The study used a sample of 94 senior secondary schools (including public and private) in FCT. Stratified…

a Latent Variable Path Analysis Model of Secondary Physics Enrollments in New York State.

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Sobolewski, Stanley John

The Percentage of Enrollment in Physics (PEP) at the secondary level nationally has been approximately 20% for the past few decades. For a more scientifically literate citizenry as well as specialists to continue scientific research and development, it is desirable that more students enroll in physics. Some of the predictor variables for physics enrollment and physics achievement that have been identified previously includes a community's socioeconomic status, the availability of physics, the sex of the student, the curriculum, as well as teacher and student data. This study isolated and identified predictor variables for PEP of secondary schools in New York. Data gathered by the State Education Department for the 1990-1991 school year was used. The source of this data included surveys completed by teachers and administrators on student characteristics and school facilities. A data analysis similar to that done by Bryant (1974) was conducted to determine if the relationships between a set of predictor variables related to physics enrollment had changed in the past 20 years. Variables which were isolated included: community, facilities, teacher experience, number of type of science courses, school size and school science facilities. When these variables were isolated, latent variable path diagrams were proposed and verified by the Linear Structural Relations computer modeling program (LISREL). These diagrams differed from those developed by Bryant in that there were more manifest variables used which included achievement scores in the form of Regents exam results. Two criterion variables were used, percentage of students enrolled in physics (PEP) and percent of students enrolled passing the Regents physics exam (PPP). The first model treated school and community level variables as exogenous while the second model treated only the community level variables as exogenous. The goodness of fit indices for the models was 0.77 for the first model and 0.83 for the second

Variability in secondary structure of 18S ribosomal RNA as topological marker for identification of Paramecium species.

Science.gov (United States)

Shakoori, Farah R; Tasneem, Fareeda; Al-Ghanim, K; Mahboob, S; Al-Misned, F; Jahan, Nusrat; Shakoori, Abdul Rauf

2014-12-01

Besides cytological and molecular applications, Paramecium is being used in water quality assessment and for determination of saprobic levels. An unambiguous identification of these unicellular eukaryotes is not only essential, but its ecological diversity must also be explored in the local environment. 18SrRNA genes of all the strains of Paramecium species isolated from waste water were amplified, cloned and sequenced. Phylogenetic comparison of the nucleotide sequences of these strains with 23 closely related Paramecium species from GenBank Database enabled identification of Paramecium multimicronucleatum and Paramecium jenningsi. Some isolates did not show significant close association with other Paramecium species, and because of their unique position in the phylogenetic tree, they were considered new to the field. In the present report, these isolates are being designated as Paramecium caudatum pakistanicus. In this article, secondary structure of 18SrRNA has also been analyzed as an additional and perhaps more reliable topological marker for species discrimination and for determining possible phylogenetic relationship between the ciliate species. On the basis of comparison of secondary structure of 18SrRNA of various isolated Paramacium strains, and among Paramecium caudatum pakistanicus, Tetrahymena thermophila, Drosophila melanogaster, and Homo sapiens, it can be deduced that variable regions are more helpful in differentiating the species at interspecific level rather than at intraspecific level. It was concluded that V3 was the least variable region in all the organisms, V2 and V7 were the longest expansion segments of D. melanogaster and there was continuous mutational bias towards G.C base pairing in H. sapiens. © 2014 Wiley Periodicals, Inc.

Period of Light Variability in BL Lac ON 231 Xu Yun Bing1, Zhang ...

Indian Academy of Sciences (India)

period light variability may be greater than the current observation history and needs further monitoring certification (Zhang et al. 1998). To establish the real periods of ON 231, we employ wavelet analysis and DCF method to search a periodicity in the light curves. 2. Periodicity analysis of ON231. 2.1 Light curve of ON 231.

Variables Affecting Secondary School Students' Willingness to Eat Genetically Modified Food Crops

Science.gov (United States)

Maes, Jasmien; Bourgonjon, Jeroen; Gheysen, Godelieve; Valcke, Martin

2017-04-01

A large-scale cross-sectional study (N = 4002) was set up to determine Flemish secondary school students' willingness to eat genetically modified food (WTE) and to link students' WTE to previously identified key variables from research on the acceptance of genetic modification (GM). These variables include subjective and objective knowledge about genetics and biotechnology, perceived risks and benefits of GM food crops, trust in information from different sources about GM, and food neophobia. Differences between WTE-related variables based on students' grade level, educational track, and gender were analyzed. The students displayed a rather indecisive position toward GM food and scored weakly on a genetics and biotechnology knowledge test. WTE correlated most strongly with perceived benefits and subjective and objective knowledge. The results have clear implications for education, as they reiterate the need to strengthen students' scientific knowledge base and to introduce a GM-related debate at a much earlier stage in their school career.

Methodology for estimation of secondary meteorological variables to be used in local dispersion of air pollutants

International Nuclear Information System (INIS)

Turtos, L.; Sanchez, M.; Roque, A.; Soltura, R.

2003-01-01

Methodology for estimation of secondary meteorological variables to be used in local dispersion of air pollutants. This paper include the main works, carried out into the frame of the project Atmospheric environmental externalities of the electricity generation in Cuba, aiming to develop methodologies and corresponding software, which will allow to improve the quality of the secondary meteorological data used in atmospheric pollutant calculations; specifically the wind profiles coefficient, urban and rural mixed high and temperature gradients

Modeling of carbonate reservoir variable secondary pore space based on CT images

Science.gov (United States)

Nie, X.; Nie, S.; Zhang, J.; Zhang, C.; Zhang, Z.

2017-12-01

Digital core technology has brought convenience to us, and X-ray CT scanning is one of the most common way to obtain 3D digital cores. However, it can only provide the original information of the only samples being scanned, and we can't modify the porosity of the scanned cores. For numerical rock physical simulations, a series of cores with variable porosities are needed to determine the relationship between the physical properties and porosity. In carbonate rocks, the secondary pore space including dissolution pores, caves and natural fractures is the key reservoir space, which makes the study of carbonate secondary porosity very important. To achieve the variation of porosities in one rock sample, based on CT scanned digital cores, according to the physical and chemical properties of carbonate rocks, several mathematical methods are chosen to simulate the variation of secondary pore space. We use the erosion and dilation operations of mathematical morphology method to simulate the pore space changes of dissolution pores and caves. We also use the Fractional Brownian Motion model to generate natural fractures with different widths and angles in digital cores to simulate fractured carbonate rocks. The morphological opening-and-closing operations in mathematical morphology method are used to simulate distribution of fluid in the pore space. The established 3D digital core models with different secondary porosities and water saturation status can be used in the study of the physical property numerical simulations of carbonate reservoir rocks.

Model atmospheres with periodic shocks. [pulsations and mass loss in variable stars

Science.gov (United States)

Bowen, G. H.

1989-01-01

The pulsation of a long-period variable star generates shock waves which dramatically affect the structure of the star's atmosphere and produce conditions that lead to rapid mass loss. Numerical modeling of atmospheres with periodic shocks is being pursued to study the processes involved and the evolutionary consequences for the stars. It is characteristic of these complex dynamical systems that most effects result from the interaction of various time-dependent processes.

Period changes of cataclysmic variables below the period gap: V2051 Oph, OY Car and Z Cha

Science.gov (United States)

Pilarčík, L.; Wolf, M.; Zasche, P.; Vraštil, J.

2018-04-01

We present our results of a long-term monitoring of cataclysmic variable stars (CVs). About 40 new eclipses were measured for the three southern SU UMa-type eclipsing CVs: V2051 Oph, OY Car and Z Cha. Based on the current O - C diagrams we confirmed earlier findings that V2051 Oph and OY Car present cyclic changes of their orbital periods lasting 25 and 29 years, respectively. In case of Z Cha we propose the light-time effect caused probably by a presence of the third component orbiting the eclipsing CV with the period of 43.5 years. The minimal mass of this companion results about 15 MJup.

A MODEL FOR (QUASI-)PERIODIC MULTIWAVELENGTH PHOTOMETRIC VARIABILITY IN YOUNG STELLAR OBJECTS

Energy Technology Data Exchange (ETDEWEB)

Kesseli, Aurora Y. [Boston University, 725 Commonwealth Ave, Boston, MA 02215 (United States); Petkova, Maya A.; Wood, Kenneth; Gregory, Scott G. [SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9AD (United Kingdom); Whitney, Barbara A. [Department of Astronomy, University of Wisconsin-Madison, 475 N. Charter St, Madison, WI 53706 (United States); Hillenbrand, L. A. [Astronomy Department, California Institute of Technology, Pasadena, CA 91125 (United States); Stauffer, J. R.; Morales-Calderon, M.; Rebull, L. [Spitzer Science Center, California Institute of Technology, CA 91125 (United States); Alencar, S. H. P., E-mail: aurorak@bu.com [Departamento de Física—ICEx—UFMG, Av. Antônio Carlos, 6627, 30270-901, Belo Horizonte, MG (Brazil)

2016-09-01

We present radiation transfer models of rotating young stellar objects (YSOs) with hot spots in their atmospheres, inner disk warps, and other three-dimensional effects in the nearby circumstellar environment. Our models are based on the geometry expected from magneto-accretion theory, where material moving inward in the disk flows along magnetic field lines to the star and creates stellar hot spots upon impact. Due to rotation of the star and magnetosphere, the disk is variably illuminated. We compare our model light curves to data from the Spitzer YSOVAR project to determine if these processes can explain the variability observed at optical and mid-infrared wavelengths in young stars. We focus on those variables exhibiting “dipper” behavior that may be periodic, quasi-periodic, or aperiodic. We find that the stellar hot-spot size and temperature affects the optical and near-infrared light curves, while the shape and vertical extent of the inner disk warp affects the mid-IR light curve variations. Clumpy disk distributions with non-uniform fractal density structure produce more stochastic light curves. We conclude that magneto-accretion theory is consistent with certain aspects of the multiwavelength photometric variability exhibited by low-mass YSOs. More detailed modeling of individual sources can be used to better determine the stellar hot-spot and inner disk geometries of particular sources.

Mind the Gap when Data Mining the Ritter-Kolb Cataclysmic Variable Catalogue

Science.gov (United States)

Sparks, Warren M.; Sion, Edward M.

2017-01-01

The cataclysmic variable (CV) binary consists of a white dwarf primary and a low-mass secondary which overflows its Roche lobe. The Ritter-Kolb catalogue (2003, A&A, 404, 301) is a collection (~1000) of CV binaries and related objects. We have mined this catalogue for CVs with unevolved secondaries whose mass ratio (secondary/primary) is known (~130). A plot of the secondary mass verses the log of the orbital period exhibits the well-known period gap at 2-3 hrs. In addition, this plot shows that the secondary masses just above the period gap are collectively much larger than those just below. The average of the first ten secondary masses above the period is 180% larger than the average below the gap.The disrupted magnetic braking hypothesis (Howell, Nelson, and Rappaport 2001, ApJ, 550, 897 [HNR]) predicts that when the secondary becomes fully convective, the magnetic braking, which has driven the secondary out of thermal equilibrium, stops. In adjusting to thermal equilibrium the secondary shrinks below its Roche lobe and no longer loses mass. The binary system ceases to appear as a CV until gravitational radiation loss brings the secondary back in contact with its Roche lobe. This scenario is at odds with the apparent secondary mass loss across the period gap. Either the secondary continues to lose mass while crossing the period gap or the secondary masses are miscalculated!Magnetic braking causes the secondary to expand or inflate larger than its single star counterpart. Any orbital parameter calculation which assumes a radius-mass relationship based on single main-sequence stars will overestimate the mass of the secondary. We can approximate this mass overestimation from calculations by HNR which take into account the thermal heating from magnetic braking. Using this approximation as a first-order correction to the secondary mass, we replot the deflated secondary mass versus the binary period. The deflated masses immediately above and below the period gap are

Prediction of primary vs secondary hypertension in children.

Science.gov (United States)

Baracco, Rossana; Kapur, Gaurav; Mattoo, Tej; Jain, Amrish; Valentini, Rudolph; Ahmed, Maheen; Thomas, Ronald

2012-05-01

Despite current guidelines, variability exists in the workup of hypertensive children due to physician preferences. The study evaluates primary vs secondary hypertension diagnosis from investigations routinely performed in hypertensive children. This retrospective study included children 5 to 19 years with primary and secondary hypertension. The proportions of abnormal laboratory and imaging tests were compared between primary and secondary hypertension groups. Risk factors for primary vs secondary hypertension were evaluated by logistic regression and likelihood function analysis. Patients with secondary hypertension were younger (5-12 years) and had a higher proportion of abnormal creatinine, renal ultrasound, and echocardiogram findings. There was no significant difference in abnormal results of thyroid function, urine catecholamines, plasma renin, and aldosterone. Abnormal renal ultrasound findings and age were predictors of secondary hypertension by regression and likelihood function analysis. Children aged 5 to 12 years with abnormal renal ultrasound findings and high diastolic blood pressures are at higher risk for secondary hypertension that requires detailed evaluation. © 2012 Wiley Periodicals, Inc.

Hydrodynamic simulations of accretion disks in cataclysmic variables

International Nuclear Information System (INIS)

Hirose, Masahito; Osaki, Yoji

1990-01-01

The tidal effects of secondary stars on accretion disks in cataclysmic variables are studied by two-dimensional hydrodynamical simulations. The time evolution of an accretion disk under a constant mass supply rate from the secondary is followed until it reaches a quasi-steady state. We have examined various cases of different mass ratios of binary systems. It is found that the accretion disk settles into a steady state of an elongated disk fixed in the rotating frame of the binary in a binary system with comparable masses of component stars. On the other hand, in the case of a low-mass secondary, the accretion disk develops a non-axisymmetric (eccentric) structure and finally settles into a periodically oscillating state in which a non-axisymmetric eccentric disk rotates in the opposite direction to the orbital motion of the binary in the rotating frame of the binary. The period of oscillation is a few percent longer than the orbital period of the binary, and it offers a natural explanation for the ''superhump'' periodicity of SU UMa stars. Our results thus confirm basically those of Whitehurst (1988, AAA 45.064.032) who discovered the tidal instability of an accretion disk in the case of a low-mass secondary. We then discuss the cause of the tidal instability. It is shown that the tidal instability of accretion disks is caused by a parametric resonance between particle orbits and an orbiting secondary star with a 1:3 period ratio. (author)

Relationship between mRNA secondary structure and sequence variability in Chloroplast genes: possible life history implications.

Science.gov (United States)

Krishnan, Neeraja M; Seligmann, Hervé; Rao, Basuthkar J

2008-01-28

Synonymous sites are freer to vary because of redundancy in genetic code. Messenger RNA secondary structure restricts this freedom, as revealed by previous findings in mitochondrial genes that mutations at third codon position nucleotides in helices are more selected against than those in loops. This motivated us to explore the constraints imposed by mRNA secondary structure on evolutionary variability at all codon positions in general, in chloroplast systems. We found that the evolutionary variability and intrinsic secondary structure stability of these sequences share an inverse relationship. Simulations of most likely single nucleotide evolution in Psilotum nudum and Nephroselmis olivacea mRNAs, indicate that helix-forming propensities of mutated mRNAs are greater than those of the natural mRNAs for short sequences and vice-versa for long sequences. Moreover, helix-forming propensity estimated by the percentage of total mRNA in helices increases gradually with mRNA length, saturating beyond 1000 nucleotides. Protection levels of functionally important sites vary across plants and proteins: r-strategists minimize mutation costs in large genes; K-strategists do the opposite. Mrna length presumably predisposes shorter mRNAs to evolve under different constraints than longer mRNAs. The positive correlation between secondary structure protection and functional importance of sites suggests that some sites might be conserved due to packing-protection constraints at the nucleic acid level in addition to protein level constraints. Consequently, nucleic acid secondary structure a priori biases mutations. The converse (exposure of conserved sites) apparently occurs in a smaller number of cases, indicating a different evolutionary adaptive strategy in these plants. The differences between the protection levels of functionally important sites for r- and K-strategists reflect their respective molecular adaptive strategies. These converge with increasing domestication levels of

A period-luminosity relation for supergiant red variables in the Large Magellanic Cloud

International Nuclear Information System (INIS)

Feast, M.W.; Catchpole, R.M.; Carter, B.S.; Roberts, G.

1980-01-01

Infrared photometry for 24 red supergiant variables in the LMC is used to derive bolometric magnitudes. The existence of a period-luminosity relation for these stars is demonstrated and compared with theory. (author)

17 CFR 270.22e-1 - Exemption from section 22(e) of the Act during annuity payment period of variable annuity...

Science.gov (United States)

2010-04-01

...) of the Act during annuity payment period of variable annuity contracts participating in certain... from section 22(e) of the Act during annuity payment period of variable annuity contracts participating... payment period of variable annuity contracts participating in such account, be exempt from the provisions...

ICUD-0147 Extreme event statistics of urban pluvial floods – Return period assessment and rainfall variability impacts

DEFF Research Database (Denmark)

Tuyls, Damian Murla; Nielsen, Rasmus; Thorndahl, Søren Liedtke

2017-01-01

A return period assessment of urban flood has been performed and its adhered impact of rainfall variability studied over a urban drainage catchment area in Aalborg, Denmark. Recorded rainfall from 7 rain gauges has been used, located in a range of 7.5Km and for a period varying form 18-37 years....... Return period of rainfall and flood at catchment and local scale has been estimated, its derived ambiguities analysed and the variability of rain gauge based rainfall investigated regarding to flood estimation results. Results show a clear contrast between rainfall and flood return period estimates...

Far Ultraviolet Spectroscopy of Three Long Period Nova-Like Variables, V363 Aur, AC Cnc and RZ Gru

Science.gov (United States)

Bisol, Alexandra; Sion, E. M.

2011-01-01

We have selected three nova-like variables: V363 Aur, RZ Gru and AC Cnc, all of which are UX UMa types, having similar orbital periods well beyond the 3 to 4 hour range where most nova-likes are found. All should have very similar secondary stars given the fact that they their physical parameters are so similar. V363 Aur is a bona fide SW Sex star, and AC Cnc is a probable one, while RZ Gru is not a member of the SW Sex subclass. Our objective is to carry out the first synthetic spectral analysis of far ultraviolet spectra of the three systems using state-of-the-art models both of accretion disks and photospheres. Therefore we shall compare the distances we obtain from the best fitting synthetic spectral models to other distance estimates in the literature. We present model-derived accretion rates and distances for all three systems. The FUV flux range of RZ Gru and V363 Aur is dominated by radiation from an optically thick, steady state, accretion but for AC Cnc, we find that a hot white dwarf accounts for 70% of the FUV flux. We compare the FUV characteristics and physical properties of these three long period nova-like systems to the properties of other nova-likes at shorter periods. This work was supported in part by NSF grant AST0807892 to Villanova University.

Structure and Evolution of Magnetic Cataclysmic Variables

Science.gov (United States)

Andronov, I. L.

2007-06-01

Theoretical models and observational results are reviewed. The general picture of the structure and evolution of cataclysmic variables (CV) is presented, together with a brief discussion of additional mechanisms of intrinsic variability of the components and magnetic activity of secondaries. Special attention is paid to the accretion structures - flow, disk, column - which are affected by the magnetic field of the white dwarf. The mass and angular momentum transfer in asynchronous MCVs leads to a "propeller" stage of rapid synchronization, after which the "idlings" of the white dwarf are altered to "swingings" with a characteristic time of century(ies). The disk- magnetic field interaction leads to precession of the white dwarf, which causes quasi-periodic changes of the equilibrium rotational period. "Shot noise" in cataclysmic variables is discussed based on one-bandpass and multi-color observations.

Evaluation of Several Learning Environment Variables at Secondary Institutions

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Murat Tuncer

2012-06-01

Full Text Available Health is an issue whose importance needs to be focused in the learning environment and learning activities in education. The level of teaching and learning is known to effect health of learners. Learning environments are teeming with many variables. Ambient temperature, noise, humidity and illumination are a few of them. If these variables are outside the specified limits for ambient levels this may need to a loss of learning and adversely affect the health of learners. This research was conducted to evaluate this aspect at institutions of secondary education in Turkey. The literature discusses the findings of various measurements that were taken with a variety of devices such as the Environment Meter-DT 8820, GMI PN 66094 and AARONIA AG SPECTRAN at randomly selected schools and classes. The temperature and carbon dioxide values in the classrooms were outside the defined limits according to research findings. In addition, many classrooms had noise levels above limits which could impair human health and some color selections in classrooms were made incorrectly. When the results of the findings are analyzed, we find the learner’s metabolism is negatively affected; attention loss and serious health problems may be experienced in the long run. It is highly recommended that laws and regulations regarding school construction and settlement be enacted and that precise limits be defined in those laws. In addition, it is thought establishing electromechanical systems to measure indoor and outdoor air quality in classrooms would bring benefits

Knowledge sharing behaviour and demographic variables amongst secondary school teachers in and around Gaborone, Botswana

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Isaac C. Mogotsi

2011-11-01

Full Text Available The purpose of this study was to investigate the relationships between knowledge sharing behaviour and the demographic variables gender, age, organisational tenure and professional tenure. Following a correlational survey approach, the study sourced its data from senior secondary school teachers in and around Gaborone, Botswana. Knowledge sharing behaviour was measured using an instrument sourced from the extant literature. No statistically significant relationship was detected between knowledge sharing behaviour and gender, age, or professional tenure. Only organisational tenure weakly negatively correlated with knowledge sharing behaviour. Thus, according to these findings, demographic variables do not appear to be important determinants of knowledge sharing behaviour.

ASSOCIATING LONG-TERM γ-RAY VARIABILITY WITH THE SUPERORBITAL PERIOD OF LS I +61°303

International Nuclear Information System (INIS)

Ackermann, M.; Buehler, R.; Ajello, M.; Ballet, J.; Casandjian, J. M.; Barbiellini, G.; Bastieri, D.; Buson, S.; Bellazzini, R.; Bregeon, J.; Bonamente, E.; Cecchi, C.; Brandt, T. J.; Brigida, M.; Bruel, P.; Caliandro, G. A.; Cameron, R. A.; Caraveo, P. A.; Cavazzuti, E.; Chekhtman, A.

2013-01-01

Gamma-ray binaries are stellar systems for which the spectral energy distribution (discounting the thermal stellar emission) peaks at high energies. Detected from radio to TeV gamma rays, the γ-ray binary LS I +61°303 is highly variable across all frequencies. One aspect of this system's variability is the modulation of its emission with the timescale set by the ∼26.4960 day orbital period. Here we show that, during the time of our observations, the γ-ray emission of LS I +61°303 also presents a sinusoidal variability consistent with the previously known superorbital period of 1667 days. This modulation is more prominently seen at orbital phases around apastron, whereas it does not introduce a visible change close to periastron. It is also found in the appearance and disappearance of variability at the orbital period in the power spectrum of the data. This behavior could be explained by a quasi-cyclical evolution of the equatorial outflow of the Be companion star, whose features influence the conditions for generating gamma rays. These findings open the possibility to use γ-ray observations to study the outflows of massive stars in eccentric binary systems

Spatial variability of soil CO2 emission in a sugarcane area characterized by secondary information

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Daniel De Bortoli Teixeira

2013-06-01

Full Text Available Soil CO2 emission (FCO2 is governed by the inherent properties of the soil, such as bulk density (BD. Mapping of FCO2 allows the evaluation and identification of areas with different accumulation potential of carbon. However, FCO2 mapping over larger areas is not feasible due to the period required for evaluation. This study aimed to assess the quality of FCO2 spatial estimates using values of BD as secondary information. FCO2 and BD were evaluated on a regular sampling grid of 60 m × 60 m comprising 141 points, which was established on a sugarcane area. Four scenarios were defined according to the proportion of the number of sampling points of FCO2 to those of BD. For these scenarios, 67 (F67, 87 (F87, 107 (F107 and 127 (F127 FCO2 sampling points were used in addition to 127 BD sampling points used as supplementary information. The use of additional information from the BD provided an increase in the accuracy of the estimates only in the F107, F67 and F87 scenarios, respectively. The F87 scenario, with the approximate ratio between the FCO2 and BD of 1.00:1.50, presented the best relative improvement in the quality of estimates, thereby indicating that the BD should be sampled at a density 1.5 time greater than that applied for the FCO2. This procedure avoided problems related to the high temporal variability associated with FCO2, which enabled the mapping of this variable to be elaborated in large areas.

Global stability of almost periodic solution of shunting inhibitory cellular neural networks with variable coefficients

International Nuclear Information System (INIS)

Chen Ling; Zhao Hongyong

2008-01-01

The paper investigates the almost periodicity of shunting inhibitory cellular neural networks with delays and variable coefficients. Several sufficient conditions are established for the existence and globally exponential stability of almost periodic solutions by employing fixed point theorem and differential inequality technique. The results of this paper are new and they complement previously known results

V2492 Cygni: Optical BVRI Variability During the Period 2010-2017

Science.gov (United States)

Ibryamov, Sunay I.; Semkov, Evgeni H.; Peneva, Stoyanka P.

2018-02-01

Results from BVRI photometric observations of the young stellar object V2492 Cyg collected during the period from August 2010 to December 2017 are presented. The star is located in the field of the Pelican Nebula and it was discovered in 2010 due to its remarkable increase in the brightness by more than 5 mag in R-band. According to the first hypothesis of the variability, V2492 Cyg is an FUor candidate. During subsequent observations, it was reported that the star shows the characteristics inherent to EXor- and UXor-type variables. The optical data show that during the whole time of observations the star exhibits multiple large amplitude increases and drops in the brightness. In the beginning of 2017, we registered a significant increase in the optical brightness of V2492 Cyg, which seriously exceeds the maximal magnitudes registered after 2010.

[Variability in smoking experimentation and risk factors in 4 secondary schools in Murcia (Spain)].

Science.gov (United States)

García, Pedro; Carrillo, Andrés; Sánchez, Joseph; Hurtado, Ascensión; Sánchez, Irene; Martínez, Rafaela; Cuevas, María Dolores

2007-01-01

To identify patterns of tobacco experimentation and consumption in 4 geographically close groups of students in the first year of secondary education, as well as attitudes and consumption in their social environments. To identify the factors associated with tobacco experimentation and consumption in each of the student groups. An observational, descriptive, cross-sectional, multicenter study was conducted in 4 secondary schools in the region of Murcia (Spain). The study population consisted of first graders in secondary education, recruited in January 2005. The study variables were collected using a modified version of the FRISC questionnaire. The study population was composed of 377 students (190 boys) with a mean age of 12.6 years (standard deviation [SD] = 0.6). Between 15.3% and 42.1% of the students had smoked at some time. Between 2% and 6.9% smoked regularly. These differences were related to socioeconomic characteristics ("living with the mother", p = 0.049; "living with the father", p = 0.015) and consumption in the environment ("mother", p = 0.013; "friends", p pocket money, consumption among friends, experimenting with alcohol and not living in one of the towns studied. Significant differences were found among the towns studied. Application of standard preventive programs may prove ineffective unless they are adapted to the characteristics of the specific school.

Spatial variability in oviposition damage by periodical cicadas in a fragmented landscape.

Science.gov (United States)

Cook, William M; Holt, Robert D; Yao, Jin

2001-03-01

Effects of the periodical cicada (Magicicada spp.) on forest dynamics are poorly documented. A 1998 emergence of M. cassini in eastern Kansas led to colonization of a fragmented experimental landscape undergoing secondary succession. We hypothesized that per-tree rates of oviposition damage by cicadas would reflect: (1) distance from the source of the emergence, (2) patch size, and (3) local tree density. Ovipositing females displayed clear preferences for host species and damage incidence showed predictable spatial patterns. Two species (smooth sumac, Rhus glabra, and eastern red cedar, Juniperus virginiana) were rarely attacked, whereas others (rough-leaved dogwood, Cornus drummondii; slippery elm, Ulmus rubra; box elder, Acer negundo, and honey locust, Gleditsia triacanthos) were strongly attacked. The dominant early successional tree, dogwood, received on average the most attacks. As predicted, attacks per stem declined strongly with distance from the emergence source, and with local stem density (a "dilution" effect). Contrary to expectations, there were more attacks per stem on larger patches. Because ovipositing cicadas cut damaging slits in host tree branches, potentially affecting tree growth rate, competitive ability, and capacity to reproduce, cicada damage could potentially influence spatial variation in secondary succession.

THE PERIOD VARIATION OF AND A SPOT MODEL FOR THE ECLIPSING BINARY AR BOOTIS

International Nuclear Information System (INIS)

Lee, Jae Woo; Youn, Jae-Hyuck; Lee, Chung-Uk; Kim, Seung-Lee; Koch, Robert H.

2009-01-01

New CCD photometric observations of the eclipsing system AR Boo were obtained from 2006 February to 2008 April. The star's photometric properties are derived from detailed studies of the period variability and of all available light curves. We find that over about 56 yr the orbital period of the system has varied due to a combination of an upward parabola and a sinusoid rather than in a monotonic fashion. Mass transfer from the less massive primary to the more massive secondary component is likely responsible for at least a significant part of the secular period change. The cyclical variation with a period of 7.57 yr and a semi-amplitude of 0.0015 d can be produced either by a light-travel-time effect due to an unseen companion with a scaled mass of M 3 sin i 3 = 0.081 M sun or by a magnetic period modulation in the secondary star. Historical light curves of AR Boo, as well as our own, display season-to-season light variability, which are best modeled by including both a cool spot and a hot one on the secondary star. We think that the spots express magnetic dynamo-related activity and offer limited support for preferring the magnetic interpretation of the 7.57 yr cycle over the third-body interpretation. Our solutions confirm that AR Boo belongs to the W-subtype contact binary class, consisting of a hotter, less massive primary star with a spectral type of G9 and a companion of spectral type K1.

Spatial variability of maximum annual daily rain under different return periods at the Rio de Janeiro state, Brazil

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Roriz Luciano Machado

2010-01-01

Full Text Available Knowledge of maximum daily rain and its return period in a region is an important tool to soil conservation, hydraulic engineering and preservation of road projects. The objective of this work was to evaluate the spatial variability of maximum annual daily rain considering different return periods, at the Rio de Janeiro State. The data set was composed by historical series of 119 rain gauges, for 36 years of observation. The return periods, estimated by Gumbel distribution, were 2, 5, 10, 25, 50 and 100 years. The spatial variability of the return periods was evaluated by semivariograms. All the return periods presented spatial dependence, with exponential and spherical model fitted to the experimental semivariograms. The parameters of the fitted semivariogram model were very similar; however, it was observed the presence of higher nugget effects for semivariograms of longer return periods. The values of maximum annual daily average rain in all the return periods increased from north to south and from countryside to the coast. In the region between the Serra do Mar range and the coast, besides increasing in magnitude, an increase in the spatial variability of the studied values with increasing return periods was also noticed. This behavior is probably caused by the orographic effect. The interpolated maps were more erratic for higher return periods and at the North, Northeast and Coastal Plain regions, in which the installation of new pluviometric stations are recommended.

Variability of Secondary Metabolites of the Species Cichorium intybus L. from Different Habitats

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Nenad M. Zlatić

2017-09-01

Full Text Available The principal aim of this paper is to show the influence of soil characteristics on the quantitative variability of secondary metabolites. Analysis of phenolic content, flavonoid concentrations, and the antioxidant activity was performed using the ethanol and ethyl acetate plant extracts of the species Cichorium intybus L. (Asteraceae. The samples were collected from one saline habitat and two non-saline habitats. The values of phenolic content from the samples taken from the saline habitat ranged from 119.83 to 120.83 mg GA/g and from non-saline habitats from 92.44 to 115.10 mg GA/g. The amount of flavonoids in the samples from the saline locality varied between 144.36 and 317.62 mg Ru/g and from non-saline localities between 86.03 and 273.07 mg Ru/g. The IC50 values of antioxidant activity in the samples from the saline habitat ranged from 87.64 to 117.73 μg/mL and from 101.44 to 125.76 μg/mL in the samples from non-saline habitats. The results confirmed that soil types represent a significant influence on the quantitative content of secondary metabolites. The greatest concentrations of phenols and flavonoids and the highest level of antioxidant activity were found in the samples from saline soil. This further corroborates the importance of saline soil as an ecological factor, as it is proven to give rise to increased biosynthesis of secondary metabolites and related antioxidant activity.

THE ACS LCID PROJECT. I. SHORT-PERIOD VARIABLES IN THE ISOLATED DWARF SPHEROIDAL GALAXIES CETUS AND TUCANA

International Nuclear Information System (INIS)

Bernard, Edouard J.; Monelli, Matteo; Gallart, Carme

2009-01-01

We present the first study of the variable star populations in the isolated dwarf spheroidal galaxies (dSphs) Cetus and Tucana. Based on Hubble Space Telescope images obtained with the Advanced Camera for Surveys in the F475W and F814W bands, we identified 180 and 371 variables in Cetus and Tucana, respectively. The vast majority are RR Lyrae stars. In Cetus, we also found three anomalous Cepheids (ACs), four candidate binaries and one candidate long-period variable (LPV), while six ACs and seven LPV candidates were found in Tucana. Of the RR Lyrae stars, 147 were identified as fundamental mode (RRab) and only eight as first-overtone mode (RRc) in Cetus, with mean periods of 0.614 and 0.363 day, respectively. In Tucana, we found 216 RRab and 82 RRc giving mean periods of 0.604 and 0.353 day. These values place both galaxies in the so-called Oosterhoff Gap, as is generally the case for dSph. We calculated the distance modulus to both galaxies using different approaches based on the properties of RRab and RRc, namely, the luminosity-metallicity and period-luminosity-metallicity relations, and found values in excellent agreement with previous estimates using independent methods: (m - M) 0,Cet = 24.46 ± 0.12 and (m - M) 0,Tuc = 24.74 ± 0.12, corresponding to 780 ± 40 kpc and 890 ± 50 kpc. We also found numerous RR Lyrae variables pulsating in both modes simultaneously (RRd): 17 in Cetus and 60 in Tucana. Tucana is, after Fornax, the second dSph in which such a large fraction of RRd (∼17%) has been observed. We provide the photometry and pulsation parameters for all the variables, and compare the latter with values from the literature for well studied dSph of the Local Group and Galactic globular clusters. The parallel WFPC2 fields were also searched for variables, as they lie well within the tidal radius of Cetus, and at its limit in the case of Tucana. No variables were found in the latter, while 15 were discovered in the outer field of Cetus (11 RRab, three RRc

X-Ray Quasi-periodic Oscillations in the Lense–Thirring Precession Model. I. Variability of Relativistic Continuum

Science.gov (United States)

You, Bei; Bursa, Michal; Życki, Piotr T.

2018-05-01

We develop a Monte Carlo code to compute the Compton-scattered X-ray flux arising from a hot inner flow that undergoes Lense–Thirring precession. The hot flow intercepts seed photons from an outer truncated thin disk. A fraction of the Comptonized photons will illuminate the disk, and the reflected/reprocessed photons will contribute to the observed spectrum. The total spectrum, including disk thermal emission, hot flow Comptonization, and disk reflection, is modeled within the framework of general relativity, taking light bending and gravitational redshift into account. The simulations are performed in the context of the Lense–Thirring precession model for the low-frequency quasi-periodic oscillations, so the inner flow is assumed to precess, leading to periodic modulation of the emitted radiation. In this work, we concentrate on the energy-dependent X-ray variability of the model and, in particular, on the evolution of the variability during the spectral transition from hard to soft state, which is implemented by the decrease of the truncation radius of the outer disk toward the innermost stable circular orbit. In the hard state, where the Comptonizing flow is geometrically thick, the Comptonization is weakly variable with a fractional variability amplitude of ≤10% in the soft state, where the Comptonizing flow is cooled down and thus becomes geometrically thin, the fractional variability of the Comptonization is highly variable, increasing with photon energy. The fractional variability of the reflection increases with energy, and the reflection emission for low spin is counterintuitively more variable than the one for high spin.

ASSOCIATING LONG-TERM {gamma}-RAY VARIABILITY WITH THE SUPERORBITAL PERIOD OF LS I +61 Degree-Sign 303

Energy Technology Data Exchange (ETDEWEB)

Ackermann, M.; Buehler, R. [Deutsches Elektronen Synchrotron DESY, D-15738 Zeuthen (Germany); Ajello, M. [Space Sciences Laboratory, 7 Gauss Way, University of California, Berkeley, CA 94720-7450 (United States); Ballet, J.; Casandjian, J. M. [Laboratoire AIM, CEA-IRFU/CNRS/Universite Paris Diderot, Service d' Astrophysique, CEA Saclay, F-91191 Gif sur Yvette (France); Barbiellini, G. [Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste (Italy); Bastieri, D.; Buson, S. [Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova (Italy); Bellazzini, R.; Bregeon, J. [Istituto Nazionale di Fisica Nucleare, Sezione di Pisa, I-56127 Pisa (Italy); Bonamente, E.; Cecchi, C. [Istituto Nazionale di Fisica Nucleare, Sezione di Perugia, I-06123 Perugia (Italy); Brandt, T. J. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Brigida, M. [Dipartimento di Fisica ' ' M. Merlin' ' dell' Universita e del Politecnico di Bari, I-70126 Bari (Italy); Bruel, P. [Laboratoire Leprince-Ringuet, Ecole polytechnique, CNRS/IN2P3, F-91128 Palaiseau (France); Caliandro, G. A. [Institute of Space Sciences (IEEE-CSIC), Campus UAB, E-08193 Barcelona (Spain); Cameron, R. A. [W. W. Hansen Experimental Physics Laboratory, Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics and SLAC National Accelerator Laboratory, Stanford University, Stanford, CA 94305 (United States); Caraveo, P. A. [INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica, I-20133 Milano (Italy); Cavazzuti, E. [Agenzia Spaziale Italiana (ASI) Science Data Center, I-00044 Frascati (Roma) (Italy); Chekhtman, A., E-mail: andrea.caliandro@ieec.uab.es, E-mail: hadasch@ieec.uab.es, E-mail: dtorres@ieec.uab.es [Center for Earth Observing and Space Research, College of Science, George Mason University, Fairfax, VA 22030 (United States); and others

2013-08-20

Gamma-ray binaries are stellar systems for which the spectral energy distribution (discounting the thermal stellar emission) peaks at high energies. Detected from radio to TeV gamma rays, the {gamma}-ray binary LS I +61 Degree-Sign 303 is highly variable across all frequencies. One aspect of this system's variability is the modulation of its emission with the timescale set by the {approx}26.4960 day orbital period. Here we show that, during the time of our observations, the {gamma}-ray emission of LS I +61 Degree-Sign 303 also presents a sinusoidal variability consistent with the previously known superorbital period of 1667 days. This modulation is more prominently seen at orbital phases around apastron, whereas it does not introduce a visible change close to periastron. It is also found in the appearance and disappearance of variability at the orbital period in the power spectrum of the data. This behavior could be explained by a quasi-cyclical evolution of the equatorial outflow of the Be companion star, whose features influence the conditions for generating gamma rays. These findings open the possibility to use {gamma}-ray observations to study the outflows of massive stars in eccentric binary systems.

Heart rate variability during pre-competition and competition periods in volleyball players

OpenAIRE

Podstawski Robert; Boraczyński Michał; Nowosielska-Swadźba Danuta; Zwolińska Danuta

2014-01-01

Study aim: Regular exercise training is thought to modify cardiac autonomic control. One of the body’s responses to training stimuli is heart rate variability (HRV). The use of HRV in the management of sport training is a common practice. The objective of the present study was to assess the impact of the physical activity level on HRV of 1st league national volleyball players prior to and during the competition period.

Heart rate variability during pre-competition and competition periods in volleyball players

Directory of Open Access Journals (Sweden)

Podstawski Robert

2014-01-01

Full Text Available Study aim: Regular exercise training is thought to modify cardiac autonomic control. One of the body’s responses to training stimuli is heart rate variability (HRV. The use of HRV in the management of sport training is a common practice. The objective of the present study was to assess the impact of the physical activity level on HRV of 1st league national volleyball players prior to and during the competition period.

Behavior of Stock Price Variability over Trading and Nontrading Periods, and Daily Return Volatility

Directory of Open Access Journals (Sweden)

Sumiyana Sumiyana

2007-09-01

This study concludes that return variance over trading and nontrading periods, along with overnight and lunch break nontrading session, and the first and second trading session, has differed significantly. In addition, daily return volatility is also not identical significantly. Subsequently, this study used size, trading volume, bid-ask spreads and up-down market as control variables. This study contradicts to all prior studies. This study especially suggests contra evidence in comparisons with previous concepts and theories in regards to size, trading volume, bid-ask spreads, and up-down market as control variables.

Global existence of periodic solutions of BAM neural networks with variable coefficients

International Nuclear Information System (INIS)

Guo Shangjiang; Huang Lihong; Dai Binxiang; Zhang Zhongzhi

2003-01-01

In this Letter, we study BAM (bidirectional associative memory) networks with variable coefficients. By some spectral theorems and a continuation theorem based on coincidence degree, we not only obtain some new sufficient conditions ensuring the existence, uniqueness, and global exponential stability of the periodic solution but also estimate the exponentially convergent rate. Our results are less restrictive than previously known criteria and can be applied to neural networks with a broad range of activation functions assuming neither differentiability nor strict monotonicity. Moreover, these conclusions are presented in terms of system parameters and can be easily verified for the globally Lipschitz and the spectral radius being less than 1. Therefore, our results should be useful in the design and applications of periodic oscillatory neural circuits for neural networks with delays

Pondering Motivational Ups and Downs throughout a Two-Month Period: A Complex Dynamic System Perspective

Science.gov (United States)

Lasagabaster, David

2017-01-01

This paper describes a two-month longitudinal study in which five secondary education students learning English as a foreign language at school will be interviewed in order to analyse how their motivation varies during this period and what variables affect their motivational changes. The emphasis will thus be on motivation's dynamicity and…

Secondary maxima in ozone profiles

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R. Lemoine

2004-01-01

Full Text Available Ozone profiles from balloon soundings as well as SAGEII ozone profiles were used to detect anomalous large ozone concentrations of ozone in the lower stratosphere. These secondary ozone maxima are found to be the result of differential advection of ozone-poor and ozone-rich air associated with Rossby wave breaking events. The frequency and intensity of secondary ozone maxima and their geographical distribution is presented. The occurrence and amplitude of ozone secondary maxima is connected to ozone variability and trend at Uccle and account for a large part of the total ozone and lower stratospheric ozone variability.

Effect of Programmed Instruction on Students' Attitude towards Structure of the Atom and the Periodic Table among Kenyan Secondary Schools

Science.gov (United States)

Wangila, M. J.; Martin, W.; Ronald, M.

2015-01-01

This study examined the effect of Programmed Instruction on students' attitude towards Structure of the Atom and the Periodic Table (SAPT) among mixed (co-educational) secondary schools of Butere district, Kakamega county, Kenya. The quasi-experimental research design was adopted, using the nonrandomized Solomon four-group as a model. The sample…

Long-Period Solar Variability

Energy Technology Data Exchange (ETDEWEB)

GAUTHIER,JOHN H.

2000-07-20

Terrestrial climate records and historical observations of the Sun suggest that the Sun undergoes aperiodic oscillations in radiative output and size over time periods of centuries and millenia. Such behavior can be explained by the solar convective zone acting as a nonlinear oscillator, forced at the sunspot-cycle frequency by variations in heliomagnetic field strength. A forced variant of the Lorenz equations can generate a time series with the same characteristics as the solar and climate records. The timescales and magnitudes of oscillations that could be caused by this mechanism are consistent with what is known about the Sun and terrestrial climate.

Non-radial oscillations of rotating stars and their relevance to the short-period oscillations of cataclysmic variables

International Nuclear Information System (INIS)

Papaloizou, J.; Pringle, J.E.

1978-01-01

The usual hypothesis, that the short-period coherent oscillations seen in cataclysmic variables are attributable to g modes in a slowly rotating white dwarf, is considered. It is shown that this hypothesis is untenable for three main reasons: (i) the observed periods are too short for reasonable white dwarf models, (ii) the observed variability of the oscillations is too rapid and (iii) the expected rotation of the white dwarf, due to accretion, invalidates the slow rotation assumption on which standard g-mode theory is based. The low-frequency spectrum of a rotating pulsating star is investigated taking the effects of rotation fully into account. In this case there are two sets of low-frequency modes, the g modes, and modes similar to Rossby waves in the Earth's atmosphere and oceans, which are designated r modes. Typical periods for such modes are 1/m times the rotation period of the white dwarfs outer layers (m is the aximuthal wavenumber). It is concluded that non-radial oscillations of rotating white dwarfs can account for the properties of the oscillations seen in dwarf novae. Application of these results to other systems is also discussed. (author)

Atmospheric kinematics of high velocity long period variables

International Nuclear Information System (INIS)

Willson, L.A.

1982-01-01

Radial velocities of atomic absorption lines of three long period variables, RT Cyg, Z Oph and S Car, have been analysed in order to understand velocity gradients and discontinuities in their atmospheres. Phase coverage is from five days before maximum to 73 days after maximum for RT Cyg, from 17 days before to 44 days after maximum for Z Oph, and at 9 days before maximum for S Car. On a few spectrograms double lines were seen. All spectrograms were analysed by a four-parameter regression programme to yield the dependence of the radial velocity on the excitation potential, first ionization potential, wavelength and line strength, as indicators of the depth of line formation. The data were analysed to yield the velocity discontinuity across shock waves and velocity gradients between shock waves. Near maximum light the radial velocities cannot be understood by the presence of one shock only but rather require two shocks. The lower shock becomes apparent at the longer wavelengths. Consistent parameters are obtained if these stars are fundamental mode pulsators with total masses in the range of 0.5 to 1.0 solar mass and effective radii in the range of 0.85 to 1.5 x 10 13 cm. (author)

UBVRI photometry of variable red dwarf emission objects

International Nuclear Information System (INIS)

Martins, D.H.

1974-01-01

A review of the history and nature of small scale variability of red dwarf emission line stars is presented. This discussion is accompanied by a description of equipment developed for the purpose of expediting data acquisition for photoelectric photometry of faint stars. Data obtained at the Kitt Peak National Observatory, the Lowell Observatory, and the Rosemary Hill Observatory of the University of Florida are tabulated and analyzed to determine their implications with respect to the known variability of four stars. BY Draconis, GT Pegasus, FF Andromeda, and LP101-15 (an eclipsing binary) are studied. LP101-15 and BY Draconis were observed on the Johnson UBVRI system at Kitt Peak while BY Draconis, GT Pegasus, and FF Andromeda were observed on the Johnson RI system at the Lowell Observatory. UBV''R'' observations were carried out on all four objects at Rosemary Hill Observatory since the spring of 1972. Analysis of the data centers on discussions relative to the proposed ''spot model'' to account for the observed variations in V, R, B--V, V--R, and R--I. After allowance is made for the influence of flare activity (found to be very important), the spot model appears to be adequate in its predictions when compared with observations. A period of 0.63398 day is supported for LP101-15, and a possible secondary minimum is proposed (this secondary eclipse would be less than 0.05 magnitude deep in V), assuming the above period to be correct. This star also appears to exhibit small scale variability with a period of 0.63398 day implying synchronous rotation and revolution. Flare activity is seen to be very important on this star as well. Continued observation of these stars and similar objects is suggested, since further data are essential for complete understanding of their behavior. (U.S.)

Supporting second grade lower secondary school students’ understanding of linear equation system in two variables using ethnomathematics

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Nursyahidah, F.; Saputro, B. A.; Rubowo, M. R.

2018-03-01

The aim of this research is to know the students’ understanding of linear equation system in two variables using Ethnomathematics and to acquire learning trajectory of linear equation system in two variables for the second grade of lower secondary school students. This research used methodology of design research that consists of three phases, there are preliminary design, teaching experiment, and retrospective analysis. Subject of this study is 28 second grade students of Sekolah Menengah Pertama (SMP) 37 Semarang. The result of this research shows that the students’ understanding in linear equation system in two variables can be stimulated by using Ethnomathematics in selling buying tradition in Peterongan traditional market in Central Java as a context. All of strategies and model that was applied by students and also their result discussion shows how construction and contribution of students can help them to understand concept of linear equation system in two variables. All the activities that were done by students produce learning trajectory to gain the goal of learning. Each steps of learning trajectory of students have an important role in understanding the concept from informal to the formal level. Learning trajectory using Ethnomathematics that is produced consist of watching video of selling buying activity in Peterongan traditional market to construct linear equation in two variables, determine the solution of linear equation in two variables, construct model of linear equation system in two variables from contextual problem, and solving a contextual problem related to linear equation system in two variables.

Personality Variables as Predictors of Leadership Role Performance Effectiveness of Administrators of Public Secondary Schools in Cross River State, Nigeria

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Akpan, Charles P.; Archibong, Ijeoma A.

2012-01-01

The study sought to find out the predictive effect of self-concept, self-efficacy, self-esteem and locus of control on the instructional and motivational leadership roles performance effectiveness of administrators of public secondary schools in Cross River State of Nigeria. The relative contribution of each of the independent variables to the…

Existence and global attractivity of positive periodic solution for competition-predator system with variable delays

International Nuclear Information System (INIS)

Zhao Hongyong; Ding Nan

2006-01-01

In this paper, Lotka-Volterra competition-predator system with variable delays is considered. Some sufficient conditions ensuring the existence and global attractivity of periodic solution for this system are obtained by using coincidence degree theory and Lyapunov functional method. An example is also worked out to demonstrate the advantages of our results

Dengue dynamics in Binh Thuan province, southern Vietnam: periodicity, synchronicity and climate variability.

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Thai, Khoa T D; Cazelles, Bernard; Nguyen, Nam Van; Vo, Long Thi; Boni, Maciej F; Farrar, Jeremy; Simmons, Cameron P; van Doorn, H Rogier; de Vries, Peter J

2010-07-13

Dengue is a major global public health problem with increasing incidence and geographic spread. The epidemiology is complex with long inter-epidemic intervals and endemic with seasonal fluctuations. This study was initiated to investigate dengue transmission dynamics in Binh Thuan province, southern Vietnam. Wavelet analyses were performed on time series of monthly notified dengue cases from January 1994 to June 2009 (i) to detect and quantify dengue periodicity, (ii) to describe synchrony patterns in both time and space, (iii) to investigate the spatio-temporal waves and (iv) to associate the relationship between dengue incidence and El Niño-Southern Oscillation (ENSO) indices in Binh Thuan province, southern Vietnam. We demonstrate a continuous annual mode of oscillation and a multi-annual cycle of around 2-3-years was solely observed from 1996-2001. Synchrony in time and between districts was detected for both the annual and 2-3-year cycle. Phase differences used to describe the spatio-temporal patterns suggested that the seasonal wave of infection was either synchronous among all districts or moving away from Phan Thiet district. The 2-3-year periodic wave was moving towards, rather than away from Phan Thiet district. A strong non-stationary association between ENSO indices and climate variables with dengue incidence in the 2-3-year periodic band was found. A multi-annual mode of oscillation was observed and these 2-3-year waves of infection probably started outside Binh Thuan province. Associations with climatic variables were observed with dengue incidence. Here, we have provided insight in dengue population transmission dynamics over the past 14.5 years. Further studies on an extensive time series dataset are needed to test the hypothesis that epidemics emanate from larger cities in southern Vietnam.

Dengue dynamics in Binh Thuan province, southern Vietnam: periodicity, synchronicity and climate variability.

Directory of Open Access Journals (Sweden)

Khoa T D Thai

2010-07-01

Full Text Available Dengue is a major global public health problem with increasing incidence and geographic spread. The epidemiology is complex with long inter-epidemic intervals and endemic with seasonal fluctuations. This study was initiated to investigate dengue transmission dynamics in Binh Thuan province, southern Vietnam.Wavelet analyses were performed on time series of monthly notified dengue cases from January 1994 to June 2009 (i to detect and quantify dengue periodicity, (ii to describe synchrony patterns in both time and space, (iii to investigate the spatio-temporal waves and (iv to associate the relationship between dengue incidence and El Niño-Southern Oscillation (ENSO indices in Binh Thuan province, southern Vietnam.We demonstrate a continuous annual mode of oscillation and a multi-annual cycle of around 2-3-years was solely observed from 1996-2001. Synchrony in time and between districts was detected for both the annual and 2-3-year cycle. Phase differences used to describe the spatio-temporal patterns suggested that the seasonal wave of infection was either synchronous among all districts or moving away from Phan Thiet district. The 2-3-year periodic wave was moving towards, rather than away from Phan Thiet district. A strong non-stationary association between ENSO indices and climate variables with dengue incidence in the 2-3-year periodic band was found.A multi-annual mode of oscillation was observed and these 2-3-year waves of infection probably started outside Binh Thuan province. Associations with climatic variables were observed with dengue incidence. Here, we have provided insight in dengue population transmission dynamics over the past 14.5 years. Further studies on an extensive time series dataset are needed to test the hypothesis that epidemics emanate from larger cities in southern Vietnam.

Complexity analyses show two distinct types of nonlinear dynamics in short heart period variability recordings

Science.gov (United States)

Porta, Alberto; Bari, Vlasta; Marchi, Andrea; De Maria, Beatrice; Cysarz, Dirk; Van Leeuwen, Peter; Takahashi, Anielle C. M.; Catai, Aparecida M.; Gnecchi-Ruscone, Tomaso

2015-01-01

Two diverse complexity metrics quantifying time irreversibility and local prediction, in connection with a surrogate data approach, were utilized to detect nonlinear dynamics in short heart period (HP) variability series recorded in fetuses, as a function of the gestational period, and in healthy humans, as a function of the magnitude of the orthostatic challenge. The metrics indicated the presence of two distinct types of nonlinear HP dynamics characterized by diverse ranges of time scales. These findings stress the need to render more specific the analysis of nonlinear components of HP dynamics by accounting for different temporal scales. PMID:25806002

Confirming Variability in the Secondary Eclipse Depth of the Super-Earth 55 Cancri e

Science.gov (United States)

Tamburo, P.; Mandell, A.; Deming, D.; Garhart, E.

2018-05-01

We present a reanalysis of five transit and eight eclipse observations of the ultrashort-period super-Earth 55 Cancri e observed using the Spitzer Space Telescope during 2011–2013. We use pixel-level decorrelation to derive accurate transit and eclipse depths from the Spitzer data, and we perform an extensive error analysis. We focus on determining possible variability in the eclipse data, as was reported in Demory et al. From the transit data, we determine updated orbital parameters, yielding T 0 = 2,455,733.0037 ± 0.0002, P = 0.7365454 ± 0.0000003 days, i = 83.5 ± 1.°3, and R p = 1.89 ± 0.05 R ⊕. Our transit results are consistent with a constant depth, and we conclude that they are not variable. We find a significant amount of variability between the eight eclipse observations and confirm agreement with Demory et al. through a correlation analysis. We convert the eclipse measurements to brightness temperatures, and generate and discuss several heuristic models that explain the evolution of the planet’s eclipse depth versus time. The eclipses are best modeled by a year-to-year variability model, but variability on shorter timescales cannot be ruled out. The derived range of brightness temperatures can be achieved by a dark planet with inefficient heat redistribution intermittently covered over a large fraction of the substellar hemisphere by reflective grains, possibly indicating volcanic activity or cloud variability. This time-variable system should be observable with future space missions, both planned (JWST) and proposed (i.e., ARIEL).

Variability in the primary emissions and secondary gas and particle formation from vehicles using bioethanol mixtures.

Science.gov (United States)

Gramsch, E; Papapostolou, V; Reyes, F; Vásquez, Y; Castillo, M; Oyola, P; López, G; Cádiz, A; Ferguson, S; Wolfson, M; Lawrence, J; Koutrakis, P

2018-04-01

Bioethanol for use in vehicles is becoming a substantial part of global energy infrastructure because it is renewable and some emissions are reduced. Carbon monoxide (CO) emissions and total hydrocarbons (THC) are reduced, but there is still controversy regarding emissions of nitrogen oxides (NO x ), aldehydes, and ethanol; this may be a concern because all these compounds are precursors of ozone and secondary organic aerosol (SOA). The amount of emissions depends on the ethanol content, but it also may depend on the engine quality and ethanol origin. Thus, a photochemical chamber was used to study secondary gas and aerosol formation from two flex-fueled vehicles using different ethanol blends in gasoline. One vehicle and the fuel used were made in the United States, and the others were made in Brazil. Primary emissions of THC, CO, carbon dioxide (CO 2 ), and nonmethane hydrocarbons (NMHC) from both vehicles decreased as the amount of ethanol in gasoline increased. NO x emissions in the U.S. and Brazilian cars decreased with ethanol content. However, emissions of THC, CO, and NO x from the Brazilian car were markedly higher than those from the U.S. car, showing high variability between vehicle technologies. In the Brazilian car, formation of secondary nitrogen dioxide (NO 2 ) and ozone (O 3 ) was lower for higher ethanol content in the fuel. In the U.S. car, NO 2 and O 3 had a small increase. Secondary particle (particulate matter [PM]) formation in the chamber decreased for both vehicles as the fraction of ethanol in fuel increased, consistent with previous studies. Secondary to primary PM ratios for pure gasoline is 11, also consistent with previous studies. In addition, the time required to form secondary PM is longer for higher ethanol blends. These results indicate that using higher ethanol blends may have a positive impact on air quality. The use of bioethanol can significantly reduce petroleum use and greenhouse gas emissions worldwide. Given the extent of

INFRARED PERIOD-LUMINOSITY RELATIONS OF EVOLVED VARIABLE STARS IN THE LARGE MAGELLANIC CLOUD

International Nuclear Information System (INIS)

Riebel, David; Meixner, Margaret; Fraser, Oliver; Srinivasan, Sundar; Cook, Kem; Vijh, Uma

2010-01-01

We combine variability information from the MAssive Compact Halo Objects survey of the Large Magellanic Cloud with infrared photometry from the Spitzer Space Telescope Surveying the Agents of a Galaxy's Evolution survey to create a data set of ∼30,000 variable red sources. We photometrically classify these sources as being on the first ascent of the red giant branch, or as being in one of three stages along the asymptotic giant branch (AGB): oxygen-rich, carbon-rich, or highly reddened with indeterminate chemistry ('extreme' AGB candidates). We present linear period-luminosity (P-L) relationships for these sources using eight separate infrared bands (J, H, K s , 3.6, 4.5, 5.8, 8.0, and 24 μm) as proxies for the luminosity. We find that the wavelength dependence of the slope of the P-L relationship is different for different photometrically determined classes of AGB stars. Stars photometrically classified as O-rich show the least variation of slope with wavelength, while dust enshrouded extreme AGB stars show a pronounced trend toward steeper slopes with increasing wavelength. We find that O-rich AGB stars pulsating in the fundamental mode obey a period-magnitude relation with a slope of -3.41 ± 0.04 when magnitude is measured in the 3.6 μm band, in contrast to C-rich AGB stars, which obey a relation of slope -3.77 ± 0.05.

Chromospheric activity of periodic variable stars (including eclipsing binaries) observed in DR2 LAMOST stellar spectral survey

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Zhang, Liyun; Lu, Hongpeng; Han, Xianming L.; Jiang, Linyan; Li, Zhongmu; Zhang, Yong; Hou, Yonghui; Wang, Yuefei; Cao, Zihuang

2018-05-01

The LAMOST spectral survey provides a rich databases for studying stellar spectroscopic properties and chromospheric activity. We cross-matched a total of 105,287 periodic variable stars from several photometric surveys and databases (CSS, LINEAR, Kepler, a recently updated eclipsing star catalogue, ASAS, NSVS, some part of SuperWASP survey, variable stars from the Tsinghua University-NAOC Transient Survey, and other objects from some new references) with four million stellar spectra published in the LAMOST data release 2 (DR2). We found 15,955 spectra for 11,469 stars (including 5398 eclipsing binaries). We calculated their equivalent widths (EWs) of their Hα, Hβ, Hγ, Hδ and Caii H lines. Using the Hα line EW, we found 447 spectra with emission above continuum for a total of 316 stars (178 eclipsing binaries). We identified 86 active stars (including 44 eclipsing binaries) with repeated LAMOST spectra. A total of 68 stars (including 34 eclipsing binaries) show chromospheric activity variability. We also found LAMOST spectra of 12 cataclysmic variables, five of which show chromospheric activity variability. We also made photometric follow-up studies of three short period targets (DY CVn, HAT-192-0001481, and LAMOST J164933.24+141255.0) using the Xinglong 60-cm telescope and the SARA 90-cm and 1-m telescopes, and obtained new BVRI CCD light curves. We analyzed these light curves and obtained orbital and starspot parameters. We detected the first flare event with a huge brightness increase of more than about 1.5 magnitudes in R filter in LAMOST J164933.24+141255.0.

Secondary organic aerosol origin in an urban environment: influence of biogenic and fuel combustion precursors.

Science.gov (United States)

Minguillón, M C; Pérez, N; Marchand, N; Bertrand, A; Temime-Roussel, B; Agrios, K; Szidat, S; van Drooge, B; Sylvestre, A; Alastuey, A; Reche, C; Ripoll, A; Marco, E; Grimalt, J O; Querol, X

2016-07-18

Source contributions of organic aerosol (OA) are still not fully understood, especially in terms of quantitative distinction between secondary OA formed from anthropogenic precursors vs. that formed from natural precursors. In order to investigate the OA origin, a field campaign was carried out in Barcelona in summer 2013, including two periods characterized by low and high traffic conditions. Volatile organic compound (VOC) concentrations were higher during the second period, especially aromatic hydrocarbons related to traffic emissions, which showed a marked daily cycle peaking during traffic rush hours, similarly to black carbon (BC) concentrations. Biogenic VOC (BVOC) concentrations showed only minor changes from the low to the high traffic period, and their intra-day variability was related to temperature and solar radiation cycles, although a decrease was observed for monoterpenes during the day. The organic carbon (OC) concentrations increased from the first to the second period, and the fraction of non-fossil OC as determined by (14)C analysis increased from 43% to 54% of the total OC. The combination of (14)C analysis and Aerosol Chemical Speciation Monitor (ACSM) OA source apportionment showed that the fossil OC was mainly secondary (>70%) except for the last sample, when the fossil secondary OC only represented 51% of the total fossil OC. The fraction of non-fossil secondary OC increased from 37% of total secondary OC for the first sample to 60% for the last sample. This enhanced formation of non-fossil secondary OA (SOA) could be attributed to the reaction of BVOC precursors with NOx emitted from road traffic (or from its nocturnal derivative nitrate that enhances night-time semi-volatile oxygenated OA (SV-OOA)), since NO2 concentrations increased from 19 to 42 μg m(-3) from the first to the last sample.

Plasma-Sheath Instability in Hall Thrusters Due to Periodic Modulation of the Energy of Secondary Electrons in Cyclotron Motion

International Nuclear Information System (INIS)

Sydorenko, D.; Smolyakov, A.; Kaganovich, I.; Raitses, Y.

2008-01-01

Particle-in-cell simulation of Hall thruster plasmas reveals a plasma-sheath instability manifesting itself as a rearrangement of the plasma sheath near the thruster channel walls accompanied by a sudden change of many discharge parameters. The instability develops when the sheath current as a function of the sheath voltage is in the negative conductivity regime. The major part of the sheath current is produced by beams of secondary electrons counter-streaming between the walls. The negative conductivity is the result of nonlinear dependence of beam-induced secondary electron emission on the plasma potential. The intensity of such emission is defined by the beam energy. The energy of the beam in crossed axial electric and radial magnetic fields is a quasi-periodical function of the phase of cyclotron rotation, which depends on the radial profile of the potential and the thruster channel width. There is a discrete set of stability intervals determined by the final phase of the cyclotron rotation of secondary electrons. As a result, a small variation of the thruster channel width may result in abrupt changes of plasma parameters if the plasma state jumps from one stability interval to another

Belongingness in Early Secondary School: Key Factors that Primary and Secondary Schools Need to Consider.

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Sharmila Vaz

Full Text Available It is unknown if, and how, students redefine their sense of school belongingness after negotiating the transition to secondary school. The current study used longitudinal data from 266 students with, and without, disabilities who negotiated the transition from 52 primary schools to 152 secondary schools. The study presents the 13 most significant personal student and contextual factors associated with belongingness in the first year of secondary school. Student perception of school belongingness was found to be stable across the transition. No variability in school belongingness due to gender, disability or household-socio-economic status (SES was noted. Primary school belongingness accounted for 22% of the variability in secondary school belongingness. Several personal student factors (competence, coping skills and school factors (low-level classroom task-goal orientation, which influenced belongingness in primary school, continued to influence belongingness in secondary school. In secondary school, effort-goal orientation of the student and perception of their school's tolerance to disability were each associated with perception of school belongingness. Family factors did not influence belongingness in secondary school. Findings of the current study highlight the need for primary schools to foster belongingness among their students at an early age, and transfer students' belongingness profiles as part of the hand-over documentation. Most of the factors that influenced school belongingness before and after the transition to secondary are amenable to change.

PERIODIC VARIABILITY OF LOW-MASS STARS IN SLOAN DIGITAL SKY SURVEY STRIPE 82

International Nuclear Information System (INIS)

Becker, A. C.; Hawley, S. L.; Ivezic, Z.; Kowalski, A. F.; Sesar, B.; Bochanski, J. J.; West, A. A.

2011-01-01

We present a catalog of periodic stellar variability in the 'Stripe 82' region of the Sloan Digital Sky Survey. After aggregating and re-calibrating catalog-level data from the survey, we ran a period-finding algorithm (Supersmoother) on all point-source light curves. We used color selection to identify systems that are likely to contain low-mass stars, in particular M dwarfs and white dwarfs. In total, we found 207 candidates, the vast majority of which appear to be in eclipsing binary systems. The catalog described in this paper includes 42 candidate M dwarf/white dwarf pairs, four white dwarf pairs, 59 systems whose colors indicate they are composed of two M dwarfs and whose light-curve shapes suggest they are in detached eclipsing binaries, and 28 M dwarf systems whose light-curve shapes suggest they are in contact binaries. We find no detached systems with periods longer than 3 days, thus the majority of our sources are likely to have experienced orbital spin-up and enhanced magnetic activity. Indeed, 26 of 27 M dwarf systems that we have spectra for show signs of chromospheric magnetic activity, far higher than the 24% seen in field stars of the same spectral type. We also find binaries composed of stars that bracket the expected boundary between partially and fully convective interiors, which will allow the measurement of the stellar mass-radius relationship across this transition. The majority of our contact systems have short orbital periods, with small variance (0.02 days) in the sample near the observed cutoff of 0.22 days. The accumulation of these stars at short orbital period suggests that the process of angular momentum loss, leading to period evolution, becomes less efficient at short periods. These short-period systems are in a novel regime for studying the effects of orbital spin-up and enhanced magnetic activity, which are thought to be the source of discrepancies between mass-radius predictions and measurements of these properties in eclipsing

NEAR-INFRARED PERIODIC AND OTHER VARIABLE FIELD STARS IN THE FIELD OF THE CYGNUS OB7 STAR-FORMING REGION

Energy Technology Data Exchange (ETDEWEB)

Wolk, Scott J.; Rice, Thomas S. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Aspin, Colin A. [Institute for Astronomy, University of Hawaii at Manoa, 640 North Aohoku Place, Hilo, HI 96720 (United States)

2013-04-15

We present a subset of the results of a three-season, 124 night, near-infrared monitoring campaign of the dark clouds Lynds 1003 and Lynds 1004 in the Cygnus OB7 star-forming region. In this paper, we focus on the field star population. Using three seasons of UKIRT J, H, and K-band observations spanning 1.5 years, we obtained high-quality photometry on 9200 stars down to J = 17 mag, with photometric uncertainty better than 0.04 mag. After excluding known disk-bearing stars we identify 149 variables-1.6% of the sample. Of these, about 60 are strictly periodic, with periods predominantly <2 days. We conclude this group is dominated by eclipsing binaries. A few stars have long period signals of between 20 and 60 days. About 25 stars have weak modulated signals, but it was not clear if these were periodic. Some of the stars in this group may be diskless young stellar objects with relatively large variability due to cool starspots. The remaining {approx}60 stars showed variations which appear to be purely stochastic.

Mean-periodic functions

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Carlos A. Berenstein

1980-01-01

Full Text Available We show that any mean-periodic function f can be represented in terms of exponential-polynomial solutions of the same convolution equation f satisfies, i.e., u∗f=0(μ∈E′(ℝn. This extends to n-variables the work of L. Schwartz on mean-periodicity and also extends L. Ehrenpreis' work on partial differential equations with constant coefficients to arbitrary convolutors. We also answer a number of open questions about mean-periodic functions of one variable. The basic ingredient is our work on interpolation by entire functions in one and several complex variables.

Painful menstrual periods

Science.gov (United States)

Menstruation - painful; Dysmenorrhea; Periods - painful; Cramps - menstrual; Menstrual cramps ... into two groups, depending on the cause: Primary dysmenorrhea Secondary dysmenorrhea Primary dysmenorrhea is menstrual pain that ...

Geographic variability of fatal road traffic injuries in Spain during the period 2002–2004: an ecological study

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Jimenez-Puente Alberto

2007-09-01

Full Text Available Abstract Background The aim of the present study is to describe the inter-province variability of Road Traffic Injury (RTI mortality on Spanish roads, adjusted for vehicle-kilometres travelled, and to assess the possible role played by the following explicative variables: sociodemographic, structural, climatic and risk conducts. Methods An ecological study design was employed. The mean annual rate of RTI deaths was calculated for the period 2002–2004, adjusted for vehicle-kilometres travelled, in the 50 provinces of Spain. The RTI death rate was related with the independent variables described above, using simple and multiple linear regression analysis with backward step-wise elimination. The level of statistical significance was taken as p Results In the period 2002–2004 there were 12,756 RTI deaths in Spain (an average of 4,242 per year, SD = 356.6. The mean number of deaths due to RTI per 100 million vehicle-kilometres (mvk travelled was 1.76 (SD = 0.51, with a minimum value of 0.66 (in Santa Cruz de Tenerife and a maximum of 3.31 (in the province of Lugo. All other variables being equal, a higher proportion of kilometres available on high capacity roads, and a higher cultural and education level were associated with lower death rates due to RTI, while the opposite was true for the rate of alcohol consumers and the road traffic volume of heavy vehicles. The variables included in the model accounted for 55.4% of the variability in RTI mortality. Conclusion Adjusting RTI mortality rates for the number of vehicle-kilometres travelled enables us to identify the high variability of this cause of death, and its relation with risk factors other than those inherent to human behaviour, such as the type of roads and the type of vehicles using them.

Acute Phase Proteins and Variables of Protein Metabolism in Dairy Cows during the Pre- and Postpartal Period

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Cs. Tóthová

2008-01-01

Full Text Available The objective of the present study was to compare the concentrations of acute phase proteins and selected variables of protein metabolism in dairy cows of the Slovak Spotted breed from 4 weeks before parturition to 10 weeks after parturition. Acute phase proteins - haptoglobin (Hp and serum amyloid A (SAA - and variables of protein metabolism - total proteins, albumin, urea, creatinine, total immunoglobulins - were evaluated in blood serum. Significant differences were found in average values of the Hp and SAA concentrations in several groups during the monitored period (P P P P P P P P P < 0.001. The above mentioned results indicate that in the time around parturition there are significant changes in concentrations of acute phase proteins, as well as in the whole protein metabolism of dairy cows. These facts suggest that the postparturient period is a critical biological phase, throughout which there is the highest incidence of metabolic disorders.

Using the Kepler Full Frame Images to Find Long-Period Variables in the Milky Way

Science.gov (United States)

Mullen, Melissa A.; Kraemer, Kathleen; Kuchar, T. A.; Sloan, G. C.

2018-01-01

We are using the monthly Full Frame Images (FFIs) images from the 4+ year Kepler mission to conduct a uniform census of long-period variables (LPVs, primarily Miras and semiregular variables) in the Milky Way disk. Our goal is to help understand how stellar pulsation and dust production interact as these dying stars eject their envelopes and enrich the interstellar medium with new fusion products and dust. To that end, we are processing the monthly FFIs for the entire 116 square-degree Kepler field to identify the LPVs and determine their period, pulsation mode, and amplitude measured with the same instrument for the 4+ year mission. Since the FFIs are not fully calibrated, we must first remove the instrumental systematics from the data and determine the flux calibration factors that can then be applied to all the stars in the field. To find these corrections, we use aperture photometry and PRF-fitting from well-characterized stars known to be stable – those with exoplanet candidates. We remove effects of the quarterly spacecraft rolls as well as longterm trends in the responsivity, which reduces the scatter in each star from 5-10% to <1-3%. We examine the effects of the optical distortions that are present in the outer parts of the array, as well as source crowding throughout the field. The fluxes from the PRF fits are typically ~1% higher than those from the aperture photometry. We present preliminary results on previously known and new, candidate, variable stars in a test field near the center of the FFIs.This work is supported by NASA ADAP grant NNX16AF45G.

Effect of climatic variability on childhood diarrhea and its high risk periods in northwestern parts of Ethiopia

Science.gov (United States)

Kumie, Abera; Worku, Alemayehu; C. Bagtzoglou, Amvrossios; Anagnostou, Emmanouil

2017-01-01

Background Increasing climate variability as a result of climate change will be one of the public health challenges to control infectious diseases in the future, particularly in sub-Saharan Africa including Ethiopia. Objective To investigate the effect of climate variability on childhood diarrhea (CDD) and identify high risk periods of diarrheal diseases. Methods The study was conducted in all districts located in three Zones (Awi, West and East Gojjam) of Amhara Region in northwestern parts of Ethiopia. Monthly CDD cases for 24 months (from July 2013 to June 2015) reported to each district health office from the routine surveillance system were used for the study. Temperature, rainfall and humidity data for each district were extracted from satellite precipitation estimates and global atmospheric reanalysis. The space-time permutation scan statistic was used to identify high risk periods of CDD. A negative binomial regression was used to investigate the relationship between cases of CDD and climate variables. Statistical analyses were conducted using SaTScan program and StataSE v. 12. Results The monthly average incidence rate of CDD was 11.4 per 1000 (95%CI 10.8–12.0) with significant variation between males [12.5 per 1000 (95%CI 11.9 to 13.2)] and females [10.2 per 1000 (95%CI 9.6 to 10.8)]. The space-time permutation scan statistic identified the most likely high risk period of CDD between March and June 2014 located in Huletej Enese district of East Gojjam Zone. Monthly average temperature and monthly average rainfall were positively associated with the rate of CDD, whereas the relative humidity was negatively associated with the rate of CDD. Conclusions This study found that the most likely high risk period is in the beginning of the dry season. Climatic factors have an association with the occurrence of CDD. Therefore, CDD prevention and control strategy should consider local weather variations to improve programs on CDD. PMID:29073259

Re-Searching Secondary Teacher Trainees in Distance Education and Face-to-Face Mode: Study of Their Background Variables, Personal Characteristics and Academic Performance

Science.gov (United States)

Garg, Mamta; Gakhar, Sudesh

2011-01-01

The present investigation was conducted to describe and compare the background variables, personal characteristics and academic performance of secondary teacher trainees in distance education and face-to-face mode. The results indicated that teacher trainees in distance education differed from their counterparts in age, marital status, sex and…

Level of Psychological Burnout of a Sample of Secondary Phase Teachers in Ma'an Governorate and Its Relationship with Some Other Variables

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Alkhateeb, Omar; Kraishan, Osama M.; Salah, Raid Omar

2015-01-01

This study aimed at identifying the level of psychological burnout of a random sample of secondary phase teacher in Ma'an Governorate and its relationship with some other variables. The study sample consisted of 80 male and female Islamic education teachers in the schools of Ma'an Governorate in the southern part of Jordan. To this end, the…

Examining the Contribution of Physical Education and Sports Courses in the Secondary School to the Sportsmanship Behaviours in Terms of Some Variables

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Serkan HACICAFEROĞLU

2015-08-01

Full Text Available This study was carried out in order to determine the contribution of the physical education and sports classes in the secondary school to the sportsmanship behaviours in terms of some variables. The population of the study, which was carried out using a general screening model, consists of students from the government - dependent secondary schools in the county, of Malatya Battalgazi, and its sampling consists of 670 students, studying at “Atatürk, Barbaros, Türk Telekom, Türkiye’m and Vakifbank” public secondary schools in the city centre of Malatya, chosen from the these schools by a random method. In the research, "Physical Education Courses Sportsmanship Behaviours Scale" is used as a data collec ting tool. Analysis of data obtained from the research was conducted with the help of a SPSS 20 package program and arithmetic mean, t - test and one - way analysis of variance (ANOVA were used in the calculation. As the result of the study, relying on the an swers the students have given to the scale it has been determined that the overall arithmetic mean of the scale was lower than expected, that the views on the contribution of the physical education and sports classes to sportsmanship behaviours were equiva lent to each other depending on the demographic variables of gender and father’s education level, however, there were significant differences among students depending on the grade level.

Minimum period and the gap in periods of Cataclysmic binaries

International Nuclear Information System (INIS)

Paczynski, B.; Sienkiewicz, R.

1983-01-01

The 81 minute cutoff to the orbital periods of hydrogen-rich cataclysmic binaries is consistent with evolution of those systems being dominated by angular momentum losses due to gravitational radiation. Unfortunately, many uncertainties, mainly poorly known atmospheric opacities below 2000 K, make is physically impossible to verify the quadrupole formula for gravitational radiation by using the observed cutoff at 81 minutes. The upper boundary of the gap in orbital periods observed at about 3 hours is almost certainly due to enhanced angular momentum losses from cataclysmic binaries which have longer periods. The physical mechanism of those losses is not identified, but a possible importance of stellar winds is pointed out. The lower boundary of the gap may be explained with the oldest cataclysmic binaries, whose periods evolved past the minimum at 81 minutes and reached the value of 2 hours within about 12 x 10 9 years after the binary had formed. Those binaries should have secondary components of only 0.02 solar masses, and their periods could be used to estimate ages of the oldest cataclysmic stars, and presumably the age of Galaxy. An alternative explanation for the gap requires that binaries should be detached while crossing the gap. A possible mechanism for this phenomenon is discussed. It requires the secondary components to be about 0.2 solar masses in the binaries just below the gap

Secondary flow in turbulent ducts with increasing aspect ratio

Science.gov (United States)

Vinuesa, R.; Schlatter, P.; Nagib, H. M.

2018-05-01

Direct numerical simulations of turbulent duct flows with aspect ratios 1, 3, 5, 7, 10, and 14.4 at a center-plane friction Reynolds number Reτ,c≃180 , and aspect ratios 1 and 3 at Reτ,c≃360 , were carried out with the spectral-element code nek5000. The aim of these simulations is to gain insight into the kinematics and dynamics of Prandtl's secondary flow of the second kind and its impact on the flow physics of wall-bounded turbulence. The secondary flow is characterized in terms of the cross-plane component of the mean kinetic energy, and its variation in the spanwise direction of the flow. Our results show that averaging times of around 3000 convective time units (based on duct half-height h ) are required to reach a converged state of the secondary flow, which extends up to a spanwise distance of around ≃5 h measured from the side walls. We also show that if the duct is not wide enough to accommodate the whole extent of the secondary flow, then its structure is modified as reflected through a different spanwise distribution of energy. Another confirmation of the extent of the secondary flow is the decay rate of kinetic energy of any remnant secondary motions for zc/h >5 (where zc is the spanwise distance from the corner) in aspect ratios 7, 10, and 14.4, which exhibits a decreasing level of energy with increasing averaging time ta, and in its rapid rate of decay given by ˜ta-1 . This is the same rate of decay observed in a spanwise-periodic channel simulation, which suggests that at the core, the kinetic energy of the secondary flow integrated over the cross-sectional area, , behaves as a random variable with zero mean, with rate of decay consistent with central limit theorem. Long-time averages of statistics in a region of rectangular ducts extending about the width of a well-designed channel simulation (i.e., extending about ≃3 h on each side of the center plane) indicate that ducts or experimental facilities with aspect ratios larger than 10 may

Management of Commonly Encountered Secondary Cleft Deformities of Face-A Case Series

Directory of Open Access Journals (Sweden)

Jacob John

2017-10-01

Full Text Available Orofacial clefts are one of the commonest congenital deformities occurring due to disturbances during the embryological formation, development and growth of orofacial region. The treatment of cleft deformities in the early period of life is mandatory to address the aesthetic, functional and psychological problems affecting the child. A considerable number of surgical modalities for definitive correction of unilateral and bilateral cleft lip, nose, and eyelid deformities have been reported over the past half century. After the initial cleft repair, there is a long period of dramatic growth. This powerful variable of growth may ultimately distort the immediate surgical result. Hence, the correction of secondary deformities plays a very important part in the care of these patients. In this article we are enlisting some simple techniques to correct the commonly encountered secondary cleft deformities of face that gave acceptable results to the patients. These corrective surgeries not only improved the function and aesthetics but also increased the confidence level, satisfaction and overall quality of life of the patient.

Radio and γ -Ray Variability in the BL Lac PKS 0219−164: Detection of Quasi-periodic Oscillations in the Radio Light Curve

Energy Technology Data Exchange (ETDEWEB)

Bhatta, Gopal, E-mail: gopalbhatta716@gmail.com [Astronomical Observatory of the Jagiellonian University, ul. Orla 171, 30-244 Kraków (Poland); Mt. Suhora Observatory, Pedagogical University, ul. Podchorazych 2, 30-084 Kraków (Poland)

2017-09-20

In this work, we explore the long-term variability properties of the blazar PKS 0219−164 in the radio and the γ -ray regime, utilizing the OVRO 15 GHz and the Fermi /LAT observations from the period 2008–2017. We found that γ -ray emission is more variable than the radio emission implying that γ -ray emission possibly originated in more compact regions while the radio emission represented continuum emission from the large-scale jets. Also, in the γ -ray, the source exhibited spectral variability, characterized by the softer-when-brighter trend, a less frequently observed feature in the high-energy emission by BL Lacs. In radio, using Lomb–Scargle periodogram and weighted wavelet z -transform, we detected a strong signal of quasi-periodic oscillation (QPO) with a periodicity of 270 ± 26 days with possible harmonics of 550 ± 42 and 1150 ± 157 day periods. At a time when detections of QPOs in blazars are still under debate, the observed QPO with high statistical significance (∼97%–99% global significance over underlying red-noise processes) and persistent over nearly 10 oscillations could make one of the strongest cases for the detection of QPOs in blazar light curves. We discuss various blazar models that might lead to the γ -ray and radio variability, QPO, and the achromatic behavior seen in the high-energy emission from the source.

Regression analysis for secondary response variable in a case-cohort study.

Science.gov (United States)

Pan, Yinghao; Cai, Jianwen; Kim, Sangmi; Zhou, Haibo

2017-12-29

Case-cohort study design has been widely used for its cost-effectiveness. In any real study, there are always other important outcomes of interest beside the failure time that the original case-cohort study is based on. How to utilize the available case-cohort data to study the relationship of a secondary outcome with the primary exposure obtained through the case-cohort study is not well studied. In this article, we propose a non-parametric estimated likelihood approach for analyzing a secondary outcome in a case-cohort study. The estimation is based on maximizing a semiparametric likelihood function that is built jointly on both time-to-failure outcome and the secondary outcome. The proposed estimator is shown to be consistent, efficient, and asymptotically normal. Finite sample performance is evaluated via simulation studies. Data from the Sister Study is analyzed to illustrate our method. © 2017, The International Biometric Society.

Sensitization predicts asthma development among wheezing toddlers in secondary healthcare.

Science.gov (United States)

Boersma, Nienke A; Meijneke, Ruud W H; Kelder, Johannes C; van der Ent, Cornelis K; Balemans, Walter A F

2017-06-01

Some wheezing toddlers develop asthma later in childhood. Sensitization is known to predict asthma in birth cohorts. However, its predictive value in secondary healthcare is uncertain. This study examines the predictive value of sensitization to inhalant allergens among wheezing toddlers in secondary healthcare for the development of asthma at school age (≥6 years). Preschool children (1-3 years) who presented with wheezing in secondary healthcare were screened on asthma at school age with the International Study of Asthma and Allergies in Childhood questionnaire. The positive and negative predictive value (PPV and NPV) of specific IgE to inhalant allergens (cut-off concentration 0.35 kU/L) and several non-invasive variables from a child's history (such as hospitalization, eczema, and parental atopy) were calculated. The additional predictive value of sensitization when combined with non-invasive predictors was examined in multivariate analysis and by ROC curves. Of 116 included children, 63% developed asthma at school age. Sensitization to inhalant allergens was a strong asthma predictor. The odds ratio (OR), PPV and NPV were 7.4%, 86%, and 55%, respectively. Eczema (OR 3.4) and hospital admission (OR 2.6) were significant non-invasive determinants. Adding sensitization to these non-invasive predictors in multivariate analysis resulted in a significantly better asthma prediction. The area under the ROC curve increased from 0.70 with only non-invasive predictors to 0.79 after adding sensitization. Sensitization to inhalant allergens is a strong predictor of school age asthma in secondary healthcare and has added predictive value when combined with non-invasive determinants. Pediatr Pulmonol. 2017;52:729-736. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Achievable data rate in spectrum-sharing channels with variable-rate variable-power primary users

KAUST Repository

Yang, Yuli; Aï ssa, Sonia

2012-01-01

In this work, we propose a transmission strategy for secondary users (SUs) within a cognitive radio network where primary users (PUs) exploit variable-rate variable-power modulation. By monitoring the PU's transmissions, the SU adjusts its transmit

Revisiting tropical instability wave variability in the Atlantic ocean using SODA reanalysis

Science.gov (United States)

de Decco, Hatsue Takanaca; Torres Junior, Audalio Rebelo; Pezzi, Luciano Ponzi; Landau, Luiz

2018-03-01

The spatial and temporal variability of energy exchange in Tropical Instability Waves (TIWs) in the Atlantic Ocean were investigated. A spectral analysis was used to filter the 5-day mean results from Simple Ocean Data Assimilation (SODA) reanalysis spanning from 1958 to 2008. TIWs were filtered over periods of 15 to 60 days and between wavelengths of 4 and 20 longitude degrees. The main approach of this study was the use of bidirectionally filtered TIW time series as the perturbation fields, and the difference in these time series from the SODA total results was considered to be the basic state for energetics analysis. The main result was that the annual cycle (period of 360 days) was the main source of variability of the waves, and the semi-annual cycle (period of 180 days) was a secondary variation, which indicated that TIWs occurred throughout the year but with intensity that varies seasonally. In SODA, barotropic instability acts as the mechanism that feeds and extracts energy to/from TIWs at equatorial Atlantic. Baroclinic instability is the main mechanism that extracts energy from TIWs to the equatorial circulation north of the Equator. All TIW patterns of variability were observed western of 10° W. The present study reveals new evidences regarding TIW variability and suggests that future investigations should include a detailed description of TIW dynamics as part of Atlantic Ocean equatorial circulation.

Painful periods (dysmenorrhea) (image)

Science.gov (United States)

Primary dysmenorrhea is a normal cramping of the lower abdomen caused by hormone-induced uterine contractions before the period. Secondary dysmenorrhea may be caused by abnormal conditions such as ...

Thyrotoxic periodic paralysis

OpenAIRE

Rojith Karandode Balakrishnan; Suresh Rama Chandran; Geetha Thirumalnesan; Nedumaran Doraisamy

2011-01-01

This article aims at highlighting the importance of suspecting thyrotoxicosis in cases of recurrent periodic flaccid paralysis; especially in Asian men to facilitate early diagnosis of the former condition. A case report of a 28 year old male patient with recurrent periodic flaccid paralysis has been presented. Hypokalemia secondary to thyrotoxicosis was diagnosed as the cause of the paralysis. The patient was given oral potassium intervention over 24 hours. The patient showed complete recove...

The Effects of Some Demografical Variables on Secondary School Students’ Images About Scientist / Bazı Demografik Özelliklerin Ortaokul Öğrencilerin Bilim İnsanı İmgeleri Üzerine Etkisi

OpenAIRE

KARAÇAM, Sedat

2016-01-01

The purpose of this study is to examine scientist images of secondary school students in terms of some demographic variables. The application was conducted in the spring semester of 2013-2014 academic year. 877 (sixth grade=420, seventh grade=457; male=438, female=439) secondary school students who study at four different secondary schools located in Düzce participated in this study. Draw A Scientist Test (DAST) was applied to determine the scientist images of students. After students complet...

Secondary amenorrhea (image)

Science.gov (United States)

Secondary amenorrhea is the cessation of menstrual flow for a period of 6 months or more in the absence ... as anxiety can be the root cause of amenorrhea. Treatment can range from behavior modification for excessive ...

Observation of a periodic runaway in the reactive Ar/O2 high power impulse magnetron sputtering discharge

Directory of Open Access Journals (Sweden)

Seyedmohammad Shayestehaminzadeh

2015-11-01

Full Text Available This paper reports the observation of a periodic runaway of plasma to a higher density for the reactive discharge of the target material (Ti with moderate sputter yield. Variable emission of secondary electrons, for the alternating transition of the target from metal mode to oxide mode, is understood to be the main reason for the runaway occurring periodically. Increasing the pulsing frequency can bring the target back to a metal (or suboxide mode, and eliminate the periodic transition of the target. Therefore, a pulsing frequency interval is defined for the reactive Ar/O2 discharge in order to sustain the plasma in a runaway-free mode without exceeding the maximum power that the magnetron can tolerate.

Periodic, complexiton solutions and stability for a (2+1)-dimensional variable-coefficient Gross-Pitaevskii equation in the Bose-Einstein condensation

Science.gov (United States)

Yin, Hui-Min; Tian, Bo; Zhao, Xin-Chao

2018-06-01

This paper presents an investigation of a (2 + 1)-dimensional variable-coefficient Gross-Pitaevskii equation in the Bose-Einstein condensation. Periodic and complexiton solutions are obtained. Solitons solutions are also gotten through the periodic solutions. Numerical solutions via the split step method are stable. Effects of the weak and strong modulation instability on the solitons are shown: the weak modulation instability permits an observable soliton, and the strong one overwhelms its development.

Infrared photometry of cataclysmic variables. II - Evidence for ellipsoidal variations in CW MoN, X Leo, IP Peg, and AF CaM

Science.gov (United States)

Szkody, P.; Mateo, M.

1986-08-01

Broadband H or K light curves of the dwarf novae CM Mon, X Leo, IP Peg, and AF Cam reveal variations that can be attributed to ellipsoidal modulation of the secondaries in these systems. The present data imply orbital periods of 4.23 + or - 0.01 hr for CW Mon and 5.0 + or - 0.1 hr for X Leo. The high-amplitude ellipsoidal modulation of the secondary of CW Mon implies a large orbital inclination. The interpretation of the low-amplitude variability seen in X Leo is complicated by details in its light curve and a recent determination of its orbital period by Shafter and Harkness (1986) which differs significantly from the period inferred from the present observations. The light variations of the eclipsing system IP Peg are interpreted as showing a 0.2 mag ellipsoidal variation from the secondary superposed on a deep eclipse of the IR light of the white dwarf and hotspot. AF Cam shows marginal evidence for a low-amplitude variation implying a very short orbital period of 76 min. IR colors of SS Aur, AH Eri, and IR Gem as well as the above four objects are used to place limits on the properties of the secondaries and the distances to these systems.

Chaos to periodicity and periodicity to chaos by periodic perturbations in the Belousov-Zhabotinsky reaction

International Nuclear Information System (INIS)

Li Qianshu; Zhu Rui

2004-01-01

A three-variable model of the Belousov-Zhabotinsky reaction system subject to external sinusoidal perturbations is investigated by means of frequency spectrum analysis. In the period-1 window of the model, the transitions from periodicity to chaos are observed; in the chaotic window, the transitions from chaos to periodicity are found. The former might be understood by the circle map of two coupled oscillators, and the latter is partly explained by the resonance between the main frequency of the chaos and the frequency of the external periodic perturbations

A NEW SUB-PERIOD-MINIMUM CATACLYSMIC VARIABLE WITH PARTIAL HYDROGEN DEPLETION AND EVIDENCE OF SPIRAL DISK STRUCTURE

International Nuclear Information System (INIS)

Littlefield, C.; Garnavich, P.; Magno, K.; Applegate, A.; Pogge, R.; Irwin, J.; Marion, G. H.; Kirshner, R.; Vinkó, J.

2013-01-01

We present time-resolved spectroscopy and photometry of CSS 120422:111127+571239 (=SBS 1108+574), a recently discovered SU UMa-type dwarf nova whose 55 minute orbital period is well below the cataclysmic variable (CV) period minimum of ∼78 minutes. In contrast with most other known CVs, its spectrum features He I emission of comparable strength to the Balmer lines, implying a hydrogen abundance less than 0.1 of long-period CVs—but still at least 10 times higher than that in AM CVn stars. Together, the short orbital period and remarkable helium-to-hydrogen ratio suggest that mass transfer in CSS 120422 began near the end of the donor star's main-sequence lifetime, meaning that this CV is a strong candidate progenitor of an AM CVn system as described by Podsiadlowski et al. Moreover, a Doppler tomogram of the Hα line reveals two distinct regions of enhanced emission. While one is the result of the stream-disk impact, the other is probably attributable to spiral disk structure generated when material in the outer disk achieves a 2:1 orbital resonance with respect to the donor.

Secondary Analysis of Large-Scale Assessment Data: An Alternative to Variable-Centred Analysis

Science.gov (United States)

Chow, Kui Foon; Kennedy, Kerry John

2014-01-01

International large-scale assessments are now part of the educational landscape in many countries and often feed into major policy decisions. Yet, such assessments also provide data sets for secondary analysis that can address key issues of concern to educators and policymakers alike. Traditionally, such secondary analyses have been based on a…

VARIABLE STARS IN THE LARGE MAGELLANIC CLOUD GLOBULAR CLUSTER NGC 2257. I. RESULTS BASED ON 2007-2008 B, V PHOTOMETRY

International Nuclear Information System (INIS)

Nemec, James M.; Walker, Alistair; Jeon, Young-Beom

2009-01-01

The variable stars in the Large Magellanic Cloud star cluster NGC 2257 are reinvestigated using photometry (to ∼20th mag) of over 400 new B, V CCD images taken with the CTIO 0.9 m telescope on 14 nights in 2007 December and 2008 January. New period searches have been made using two independent algorithms (CLEAN, Period04); the resultant periods of most of the stars are consistent with the pulsation periods derived previously, and where there are discrepancies these have been resolved. For the B and V light curves, accurate Fourier coefficients and parameters are given. Six new variable stars have been discovered (V45-50), including a bright candidate long-period variable star showing secondary oscillations (V45) and two anomalously bright RRc stars (V48 and V50), which are shown to be brightened and reddened by nearby red giant stars. Also discovered among the previously known variable stars are three double-mode RR Lyrae stars (V8, V16, and V34) and several Blazhko variables. Archival Hubble Space Telescope images and the photometry by Johnson et al. have been used to define better the properties of the most crowded variable stars. The total number of cluster variable stars now stands at forty-seven: 23 RRab stars, four of which show Blazhko amplitude variations; 20 RRc stars, one showing clear Blazhko variations and another showing possible Blazhko variations; the three RRd stars, all having the dominant period ∼0.36 day and period ratios P 1 /P 0 ∼0.7450; and an LPV star located near the tip of the red giant branch. A comparison of the RRd stars with those in other environments shows them to be most similar to those in IC4499.

Genome variability of foot-and-mouth disease virus during the short period of the 2010 epidemic in Japan.

Science.gov (United States)

Nishi, Tatsuya; Yamada, Manabu; Fukai, Katsuhiko; Shimada, Nobuaki; Morioka, Kazuki; Yoshida, Kazuo; Sakamoto, Kenichi; Kanno, Toru; Yamakawa, Makoto

2017-02-01

Foot-and-mouth disease virus (FMDV) is highly contagious and has a high mutation rate, leading to extensive genetic variation. To investigate how FMDV genetically evolves over a short period of an epidemic after initial introduction into an FMD-free area, whole L-fragment sequences of 104 FMDVs isolated from the 2010 epidemic in Japan, which continued for less than three months were determined and phylogenetically and comparatively analyzed. Phylogenetic analysis of whole L-fragment sequences showed that these isolates were classified into a single group, indicating that FMDV was introduced into Japan in the epidemic via a single introduction. Nucleotide sequences of 104 virus isolates showed more than 99.56% pairwise identity rates without any genetic deletion or insertion, although no sequences were completely identical with each other. These results indicate that genetic substitutions of FMDV occurred gradually and constantly during the epidemic and generation of an extensive mutant virus could have been prevented by rapid eradication strategy. From comparative analysis of variability of each FMDV protein coding region, VP4 and 2C regions showed the highest average identity rates and invariant rates, and were confirmed as highly conserved. In contrast, the protein coding regions VP2 and VP1 were confirmed to be highly variable regions with the lowest average identity rates and invariant rates, respectively. Our data demonstrate the importance of rapid eradication strategy in an FMD epidemic and provide valuable information on the genome variability of FMDV during the short period of an epidemic. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Variable impedance cardiography waveforms: how to evaluate the preejection period more accurately

International Nuclear Information System (INIS)

Ermishkin, V V; Kolesnikov, V A; Lukoshkova, E V; Mokh, V P; Sonina, R S; Dupik, N V; Boitsov, S A

2012-01-01

Impedance method has been successfully applied for left ventricular function assessment during functional tests. The preejection period (PEP), the interval between Q peak in ECG and a specific mark on impedance cardiogram (ICG) which corresponds to aortic valve opening, is an important indicator of the contractility state and its neurogenic control. Accurate identification of ejection onset by ICG is often problematic, especially in the cardiologic patients, due to peculiar waveforms. An essential obstacle is variability of the shape of the ICG waveform during the exercise and subsequent recovery. A promissing solution can be introduction of an additional pulse sensor placed in the nearby region. We tested this idea in 28 healthy subjects and 6 cardiologic patients using a dual-channel impedance cardiograph for simultaneous recording from the aortic and neck regions, and an earlobe photoplethysmograph. Our findings suggest that incidence of abnormal complicated ICG waveforms increases with age. The combination of standard ICG with ear photoplethysmography and/or additional impedance channel significantly improves the efficacy and accuracy of PEP estimation.

Achievable data rate in spectrum-sharing channels with variable-rate variable-power primary users

KAUST Repository

Yang, Yuli

2012-08-01

In this work, we propose a transmission strategy for secondary users (SUs) within a cognitive radio network where primary users (PUs) exploit variable-rate variable-power modulation. By monitoring the PU\\'s transmissions, the SU adjusts its transmit power based on the gap between the PU\\'s received effective signal-to-noise power ratio (SNR) and the lower SNR boundary for the modulation mode that is being used in the primary link. Thus, at the SU\\'s presence, the PU\\'s quality of service (QoS) is guaranteed without increasing its processing complexity thanks to no interference cancellation required in the PU\\'s operation. To demonstrate the advantage of our proposed transmission strategy, we analyze the secondary user\\'s achievable data rate by taking into account different transmission capabilities for the secondary transmitter. The corresponding numerical results not only prove the validity of our derivations but also provide a convenient tool for the network design with the proposed transmission strategy. © 2012 IEEE.

Variable Stars Observed in the Galactic Disk by AST3-1 from Dome A, Antarctica

Energy Technology Data Exchange (ETDEWEB)

Wang, Lingzhi; Ma, Bin; Hu, Yi; Liu, Qiang; Shang, Zhaohui [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Li, Gang; Fu, Jianning [Department of Astronomy, Beijing Normal University, Beijing, 100875 (China); Wang, Lifan; Cui, Xiangqun; Du, Fujia; Gong, Xuefei; Li, Xiaoyan; Li, Zhengyang; Yuan, Xiangyan; Zhou, Jilin [Chinese Center for Antarctic Astronomy, Nanjing 210008 (China); Ashley, Michael C. B. [School of Physics, University of New South Wales, NSW 2052 (Australia); Pennypacker, Carl R. [Center for Astrophysics, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); York, Donald G., E-mail: wanglingzhi@bao.ac.cn [Department of Astronomy and Astrophysics and Enrico Fermi Institute, University of Chicago, Chicago, IL 60637 (United States)

2017-03-01

AST3-1 is the second-generation wide-field optical photometric telescope dedicated to time-domain astronomy at Dome A, Antarctica. Here, we present the results of an i -band images survey from AST3-1 toward one Galactic disk field. Based on time-series photometry of 92,583 stars, 560 variable stars were detected with i magnitude ≤16.5 mag during eight days of observations; 339 of these are previously unknown variables. We tentatively classify the 560 variables as 285 eclipsing binaries (EW, EB, and EA), 27 pulsating variable stars ( δ Scuti, γ Doradus, δ Cephei variable, and RR Lyrae stars), and 248 other types of variables (unclassified periodic, multiperiodic, and aperiodic variable stars). Of the eclipsing binaries, 34 show O’Connell effects. One of the aperiodic variables shows a plateau light curve and another variable shows a secondary maximum after peak brightness. We also detected a complex binary system with an RS CVn-like light-curve morphology; this object is being followed-up spectroscopically using the Gemini South telescope.

Global Magnetic Variability at Planetary Wave Periods

Science.gov (United States)

Forbes, J. M.; Behm, J.

2017-12-01

Planetary waves (PW) and PW-tide interactions are thought to introduce multi-day periodicities ( 2-20 days) in the electric fields and currents induced by the wind dynamo mechanism in the ionospheric E-region (ca. 100-150 km), and thus can provide important insights on coupling between the lower atmosphere and the ionosphere. Previous studies have used a relatively small subset of available data to infer the existence of these variations in ground magnetic measurements. In some cases connections were made with contemporaneous measurements of neutral wind dynamics. In the present work, we employ ground-based magnetometer data from over 100 stations from the INTERMAGNET network during 2009 to gain a global perspective on eastward- and westward-propagating and zonally-symmetric oscillations with PW periods. Our presentation describes how the unevenly-spaced global data are re-gridded onto an icosahedral grid prior to analysis, and assesses how gaps in the distribution of points across the grid affect extraction of some parts of the spectrum. Consideration is also given to possible contamination by recurrent magnetic activity at subharmonics of 27 days. The global evolution of several PW components during 2009 are depicted and interpreted.

Facing unprecedented drying of the Central Andes? Precipitation variability over the period AD 1000–2100

International Nuclear Information System (INIS)

Neukom, Raphael; Salzmann, Nadine; Huggel, Christian; Rohrer, Mario; Calanca, Pierluigi; Acuña, Delia; Christie, Duncan A; Morales, Mariano S

2015-01-01

Projected future trends in water availability are associated with large uncertainties in many regions of the globe. In mountain areas with complex topography, climate models have often limited capabilities to adequately simulate the precipitation variability on small spatial scales. Also, their validation is hampered by typically very low station density. In the Central Andes of South America, a semi-arid high-mountain region with strong seasonality, zonal wind in the upper troposphere is a good proxy for interannual precipitation variability. Here, we combine instrumental measurements, reanalysis and paleoclimate data, and a 57-member ensemble of CMIP5 model simulations to assess changes in Central Andes precipitation over the period AD 1000–2100. This new database allows us to put future projections of precipitation into a previously missing multi-centennial and pre-industrial context. Our results confirm the relationship between regional summer precipitation and 200 hPa zonal wind in the Central Andes, with stronger Westerly winds leading to decreased precipitation. The period of instrumental coverage (1965–2010) is slightly dryer compared to pre-industrial times as represented by control simulations, simulations from the past Millennium, ice core data from Quelccaya ice cap and a tree-ring based precipitation reconstruction. The model ensemble identifies a clear reduction in precipitation already in the early 21st century: the 10 year running mean model uncertainty range (ensemble 16–84% spread) is continuously above the pre-industrial mean after AD 2023 (AD 2028) until the end of the 21st century in the RCP2.6 (RCP8.5) emission scenario. Average precipitation over AD 2071–2100 is outside the range of natural pre-industrial variability in 47 of the 57 model simulations for both emission scenarios. The ensemble median fraction of dry years (defined by the 5th percentile in pre-industrial conditions) is projected to increase by a factor of 4 until 2071�

Ambient Levels of Primary and Secondary Pollutants in a Residential Area: Population Risk and Hazard Index Calculation over a Three Years Study Period

OpenAIRE

S. Al-Salem; A. Al-Fadhlee

2007-01-01

This paper aims at presenting data collected over the period of three years (2004-2006) in a residential area in the state of Kuwait. The data collected include ambient levels of primary and secondary pollutants with a number of metrological parameters. A series of unfiltered and filtered concentration roses were plotted to determine the predominant sources as well as the prevailing winds affecting the area under investigation. Local and international air quality regulations were cross refere...

Localized lesions in secondary syphillis

International Nuclear Information System (INIS)

Rasid, N.; Syphilis, S.

2008-01-01

The clinical manifestations of secondary syphilis are variable and can mimic many skin diseases, mostly being generalized and symmetrical in distribution. Localized lesions of secondary syphilis are rarely seen in dermatology clinics. We report an unusual presentation wherein a patient had localized lesions over face and soles only. There is a need for increased awareness on the part of physicians to recognize new patterns of syphilitic infection, together with a willingness to consider the diagnosis of syphilis in patients with unusual clinical features. (author)

Associations between period 3 gene polymorphisms and sleep- /chronotype-related variables in patients with late-life insomnia.

Science.gov (United States)

Mansour, Hader A; Wood, Joel; Chowdari, Kodavali V; Tumuluru, Divya; Bamne, Mikhil; Monk, Timothy H; Hall, Martica H; Buysse, Daniel J; Nimgaonkar, Vishwajit L

2017-01-01

A variable number tandem repeat polymorphism (VNTR) in the period 3 (PER3) gene has been associated with heritable sleep and circadian variables, including self-rated chronotypes, polysomnographic (PSG) variables, insomnia and circadian sleep-wake disorders. This report describes novel molecular and clinical analyses of PER3 VNTR polymorphisms to better define their functional consequences. As the PER3 VNTR is located in the exonic (protein coding) region of PER3, we initially investigated whether both alleles (variants) are transcribed into messenger RNA in human fibroblasts. The VNTR showed bi-allelic gene expression. We next investigated genetic associations in relation to clinical variables in 274 older adult Caucasian individuals. Independent variables included genotypes for the PER3 VNTR as well as a representative set of single nucleotide polymorphisms (SNPs) that tag common variants at the PER3 locus (linkage disequilibrium (LD) between genetic variants sleep time and sleep latency, self-rated chronotype, estimated with the Composite Scale (CS), and lifestyle regularity, estimated using the social rhythm metric (SRM). Initially, genetic polymorphisms were individually analyzed in relation to each outcome variable using analysis of variance (ANOVA). Nominally significant associations were further tested using regression analyses that incorporated individual ANOVA-associated DNA variants as potential predictors and each of the selected sleep/circadian variables as outcomes. The covariates included age, gender, body mass index and an index of medical co-morbidity. Significant genetic associations with the VNTR were not detected with the sleep or circadian variables. Nominally significant associations were detected between SNP rs1012477 and CS scores (p = 0.003) and between rs10462021 and SRM (p = 0.047); rs11579477 and average delta power (p = 0.043) (analyses uncorrected for multiple comparisons). In conclusion, alleles of the VNTR are expressed at the

Speleothem records of western Mediterranean. Hydrological variability along the Last Interglacial Period and marine linkages

Science.gov (United States)

Torner, Judit; Cacho, Isabel; Moreno, Ana; Stoll, Heather; Belmonte, Anchel; Sierro, Francisco J.; Frigola, Jaime; Martrat, Belen; Fornós, Joan; Arnau Fernández, Pedro; Hellstrom, John; Cheng, Hai; Edwards, R. Lawrence

2016-04-01

This study aims to identify and characterize regional hydrological variability in the western Mediterranean region in base to different geochemical parameters (δ18O, δ13C, and Mg/Ca ratios). Speleothems have been recovered from several caves located in southern central Pyrenees one and the others form the Balearic Islands. Their chronologies have been constructed in base on U/Th absolute dating and indicate that the speleothem sequences cover the end of the last interglacial and the glacial inception. One of the most remarkable features of the records is the intense and abrupt shift toward more arid conditions that marks the end of the last interglacial (MIS 5e). Furthermore, our speleothem records also show relatively humid but highly variable hydrological conditions during the interstadial periods from MIS 5c to 5a. These speleothem records have been compared with new generated western Mediterranean marine records from the Balearic Sea (MD99-2343) and Alboran Sea (OPD-977). Marine records include (1) proxies of sea surface temperature and changes in evaporation-precipitation rates based on pair analysis of δ18O and the Mg/Ca ratios in planktonic foraminifera Globigerina bulloides; (2) proxies of deep-water currents associated with the Western Mediterranean Deep Water (WMDW) based on grain size analyses. The results reveal that arid conditions on land were coeval with cold sea surface sub-stages (MIS 5b and 5d), and also with increases in the intensity of the WMDW-related currents. By contrast, humid and hydrological unstable atmosphere conditions were synchronous with sea surface warm sub-stages, and lower WMDW-related currents intensities (MIS 5a, c and e). Consequently, our results highly evidence a strong atmospheric-oceanic coupling, involving parallel changes in both surface but also deep western Mediterranean Sea conditions during the last interglacial period and the glacial inception.

6-year periodicity and variable synchronicity in a mass-flowering plant.

Directory of Open Access Journals (Sweden)

Satoshi Kakishima

Full Text Available Periodical organisms, such as bamboos and periodical cicadas, are very famous for their synchronous reproduction. In bamboos and other periodical plants, the synchronicity of mass-flowering and withering has been often reported indicating these species are monocarpic (semelparous species. Therefore, synchronicity and periodicity are often suspected to be fairly tightly coupled traits in these periodical plants. We investigate the periodicity and synchronicity of Strobilanthes flexicaulis, and a closely related species S. tashiroi on Okinawa Island, Japan. The genus Strobilanthes is known for several periodical species. Based on 32-year observational data, we confirmed that S. flexicaulis is 6-year periodical mass-flowering monocarpic plant. All the flowering plants had died after flowering. In contrast, we found that S. tashiroi is a polycarpic perennial with no mass-flowering from three-year individual tracking. We also surveyed six local populations of S. flexicaulis and found variation in the synchronicity from four highly synchronized populations (>98% of plants flowering in the mass year to two less synchronized one with 11-47% of plants flowering before and after the mass year. This result might imply that synchrony may be selected for when periodicity is established in monocarpic species. We found the selective advantages for mass-flowering in pollinator activities and predator satiation. The current results suggest that the periodical S. flexicaulis might have evolved periodicity from a non-periodical close relative. The current report should become a key finding for understanding the evolution of periodical plants.

The validity of the PAM-RL device for evaluating periodic limb movements in sleep and an investigation on night-to-night variability of periodic limb movements during sleep in patients with restless legs syndrome or periodic limb movement disorder using this system.

Science.gov (United States)

Kobayashi, Mina; Namba, Kazuyoshi; Ito, Eiki; Nishida, Shingo; Nakamura, Masaki; Ueki, Yoichiro; Furudate, Naomichi; Kagimura, Tatsuo; Usui, Akira; Inoue, Yuichi

2014-01-01

The status of night-to-night variability for periodic limb movements in sleep (PLMS) has not been clarified. With this in mind, we investigated the validity of PLMS measurement by actigraphy with the PAM-RL device in Japanese patients with suspected restless legs syndrome (RLS) or periodic limb movement disorder (PLMD) and the night-to-night variability of PLMS among the subjects. Forty-one subjects (mean age, 52.1±16.1 years) underwent polysomnography (PSG) and PAM-RL measurement simultaneously. Thereafter, subjects used the PAM-RL at home on four more consecutive nights. The correlation between PLMS index on PSG (PLMSI-PSG) and PLM index on PAM-RL (PLMI-PAM) was 0.781 (PPAM-RL. PAM-RL is thought to be valuable for assessing PLMS even in Japanese subjects. Recording of PAM-RL for three or more consecutive nights may be required to ensure the screening reliability of a patient with suspected pathologically frequent PLMS. Copyright © 2013 Elsevier B.V. All rights reserved.

Variables that influence junior secondary school students‟ attitude ...

African Journals Online (AJOL)

The positive relationship between the rate of learning, attitude to and achievement in science has been documented in literature. It is therefore pertinent to assess the variables that tend to influence students' attitude to Agricultural Science. The study assessed the influence of gender, location of school and sex composition ...

Who theorizes age? The "socio-demographic variables" device and age-period-cohort analysis in the rhetoric of survey research.

Science.gov (United States)

Rughiniș, Cosima; Humă, Bogdana

2015-12-01

In this paper we argue that quantitative survey-based social research essentializes age, through specific rhetorical tools. We outline the device of 'socio-demographic variables' and we discuss its argumentative functions, looking at scientific survey-based analyses of adult scientific literacy, in the Public Understanding of Science research field. 'Socio-demographics' are virtually omnipresent in survey literature: they are, as a rule, used and discussed as bundles of independent variables, requiring little, if any, theoretical and measurement attention. 'Socio-demographics' are rhetorically effective through their common-sense richness of meaning and inferential power. We identify their main argumentation functions as 'structure building', 'pacification', and 'purification'. Socio-demographics are used to uphold causal vocabularies, supporting the transmutation of the descriptive statistical jargon of 'effects' and 'explained variance' into 'explanatory factors'. Age can also be studied statistically as a main variable of interest, through the age-period-cohort (APC) disambiguation technique. While this approach has generated interesting findings, it did not mitigate the reductionism that appears when treating age as a socio-demographic variable. By working with age as a 'socio-demographic variable', quantitative researchers convert it (inadvertently) into a quasi-biological feature, symmetrical, as regards analytical treatment, with pathogens in epidemiological research. Copyright © 2015 Elsevier Inc. All rights reserved.

[The effects of 16-weeks pilates mat program on anthropometric variables and body composition in active adult women after a short detraining period].

Science.gov (United States)

Vaquero-Cristóbal, Raquel; Alacid, Fernando; Esparza-Ros, Francisco; Muyor, José M; López-Miñarro, Pedro Ángel

2015-04-01

previous studies have analysed the effect of mat Pilates practice on anthropometric variables and body composition in sedentaries. To date no researchs have investigated the benefits of Pilates on these variables after a short detraining period. to determine the effect of a 16-week mat Pilates program on anthropometric variables, body composition and somatotype of women with previous practice experience after three weeks of detraining period. twenty-one women underwent a complete anthropometric assessment according with ISAK guidelines before and after a 16 week mat Pilates program (two days, one hour). All women had one to three years of mat Pilates experience and came to three weeks of detraining period (Christmas holiday). women showed significant decreases for body mass, BMI, upper limb (biceps and triceps) and trunk (subscapular, iliac crest, supraspinale and abdominal) individual skinfolds, 6 and 8 skinfold sums, endomorphy and fat mass; and a significant increases for muscle mass. The mean somatotype was classified as mesomorphic endomorph in the pre- (4.91, 4.01, 1.47) and post-test (4.68, 4.16, 1.69). Eight women changed their somatotype clasification after the intervention program. the practice of mat Pilates for 16 weeks caused changes associated with health state improvements on anthropometric variables, especially on skinfolds which significantly decreased, body composition (fat and muscle masses decreased and increased, respectively) and somatotype (there was a significantly decreased on the endomorph component in experienced women after three week of detraning. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Completion of Upper Secondary Education: What Mechanisms Are at Stake?

DEFF Research Database (Denmark)

Munk, Martin D.

2013-01-01

also investigate the importance of characteristics other than the traditional variables, such as fathers’ and mothers’ occupations, their education and household income, often applied in studies of educational attainment. I used a recent 1984 cohort database with information about educational...... completion and an informative set of measurements on non-cognitive capacities, parental cultural capital, cultural capital, reading score, several school-related variables, and a rich set of family background variables. Attainment of upper secondary education was analyzed by a multinomial logit model......, showing that characteristics other than the traditional variables all have significant importance. The analysis clearly depicted that the social position and educational levels of both parents remain important in determining whether the child embarks on completing an upper secondary education...

Effects of age, task, and frequency on variability of finger tapping.

Science.gov (United States)

Sommervoll, Yngve; Ettema, Gertjan; Vereijken, Beatrix

2011-10-01

The goal was to assess whether prior studies might have overestimated performance variability in older adults in dual task conditions by relying on primary motor tasks that are not constant with aging. 30 younger and 31 older adults performed a bimanual tapping task at four different frequencies in isolation or concurrently with a secondary task. Results showed that performance of younger and older adults was not significantly different in performing the tapping task at all frequencies and with either secondary task, as indicated by mean tapping performance and low number of errors in the secondary tasks. Both groups showed increased variability as tapping frequency increased and with the presence of a secondary task. Tapping concurrently while reading words increased tapping variability more than tapping concurrently while naming colours. Although older participants' performances were overall more variable, no interaction effects with age were found and at the highest frequencies of tapping, younger and older participants did not differ in performance.

Features of the heart rate variability in the perioperative period after adenotomy in children

Directory of Open Access Journals (Sweden)

Михайло Борисович Пушкар

2015-03-01

Full Text Available Aim. Study course of perioperative period after adenotomy in children in different ways of general anesthesia by examining indicators of heart rate variability and efficacy of postoperative analgesia.Materials and methods. To study included 70 children aged from 6 to 8 years, which was held adenotomy. Patients were divided into 3 groups: group I (n = 28 - operated under conditions of intravenous anesthesia based on propofol combined with fentanyl; group II (n=23 – operated under conditions of inhalation anesthesia by sevoflurane in combination with fentanyl and analginum; group III (n=19 – operated under conditions of intravenous anesthesia based on thiopental sodium combined with fentanyl. Differences were considered significant at p <0.05 using Student t-test.Results. Indicators of heart rate variability indicated that in the extubation stage in all groups of patients revealed high activity of the sympathetic tone with the trend of decline in the morning after surgery. Statistically higher activity of the sympathetic part of the autonomic nervous system was in patients of group III - 1 hour after surgery compared with patients groups I and II (p <0,001 and p <0,01, respectively. After 1 hour after surgery on the scales "Faces" and "Oucher" scores indicated that the child "a little hurt" in all groups of patients In the dynamics of observation in all groups tended to reduce the intensity of pain. An interpretation of scores on the FLACC scale indicated that patients in both groups felt comfortable.Conclusions. It was found that in patients in all groups there are changes in the nervous regulation of heart rate variability, characterized by increased activity of the sympathetic division of the autonomic nervous system. Postoperative anesthesia by 10 mg / kg ibuprofen provides effective analgesia

Relationship of classical novae to other eruptive variables

International Nuclear Information System (INIS)

Vogt, N.

1989-01-01

Classical novae are characterized by their well known large-amplitude outbursts, accompanied by the ejection of a shell. The same stars, however, apparently pass through much longer quiescent phases whose duration exceeds that of the outburst phase by a factor ∼ 10 5 and that of historical nova records by a factor 10 2 -10 3 . Therefore a large number of variable stars should exist which actually are classical nova systems but whose last outbursts occurred in prehistoric times. We assume that some of these stars are hidden among the so-called 'nova-lies' in the literature. However some eruptive variables and symbiotic stars, i.e. stars which certainly are not nova remnants, are mentioned. Variables related to classical novae can be divided into three main classes: (i) Potential novae which are possibly classical novae in their quiescent state. Potential novae must share the basic configuration and parameters (orbital period, masses) with classical novae; they must be semi-detached cataclysmic binaries with a white dwarf as primary and a Roche-lobe-filling red dwarf on, or near, the mainsequence as secondary. (ii) Stars which share some outburst characteristics with classical novae without having the same binary configuration. For example recurrent novae with giant secondaries, very slow novae (and symbiotic binary stars). (iii) Stars which are evolutionarily related to classical novae, i.e. which possibly are progenitors or successors of novae in their secular evolution, such as binary nuclei of planetary nebulae and close, but detached, white dwarf-red dwarf pairs (e.g. V 471 Tau), both resulting from common-envelope evolution. These three main groups of nova-related stars are discussed. (author)

Periodic radio variability in NRAO 530: phase dispersion minimization analysis

International Nuclear Information System (INIS)

Lu Junchao; Lin Jiming; Qiu Hongbing; Wang Junyi; An Tao

2012-01-01

A periodicity analysis of the radio light curves of the blazar NRAO 530 at 14.5, 8.0, and 4.8 GHz is presented employing an improved phase dispersion minimization technique. The result, which shows two persistent periodic components of ∼ 6 and ∼ 10 yr at all three frequencies, is consistent with the results obtained with the Lomb-Scargle periodogram and weighted wavelet Z-transform algorithms. The reliability of the derived periodicities is confirmed by the Monte Carlo numerical simulations which show a high statistical confidence. (Quasi-)Periodic fluctuations of the radio luminosity of NRAO 530 might be associated with the oscillations of the accretion disk triggered by hydrodynamic instabilities of the accreted flow. (research papers)

Further Results on Extended Delivery Time for Secondary Packet Transmission

KAUST Repository

Usman, Muneer

2017-07-10

Cognitive radio transceiver can opportunistically access the underutilized spectrum resource of primary systems for new wireless services. With interweave cognitive implementation, secondary transmission may be interrupted by primary transmission. To facilitate the packet delay analysis of such secondary transmission, we study the extended delivery time of secondary packet transmission. In particular, we derive the exact distribution function of extended delivery time of a fixed-size secondary packet with non-work-preserving strategy, where interrupted packets must be repeated. We also analyze the effect of imperfect periodic sensing, i.e., the secondary user periodically senses the spectrum for availability, with a chance of missing an available channel on a certain sensing attempt. These results complement previous work on work-preserving strategy with perfect sensing. Selected numerical and simulation results are presented for verifying the mathematical formulation.

Secondary osteoporosis.

Science.gov (United States)

Gennari, C; Martini, G; Nuti, R

1998-06-01

Generalized osteoporosis currently represents a heterogeneous group of conditions with many different causes and pathogenetic mechanisms, that often are variably associated. The term "secondary" is applied to all patients with osteoporosis in whom the identifiable causal factors are other than menopause and aging. In this heterogeneous group of conditions, produced by many different pathogenetic mechanisms, a negative bone balance may be variably associated with low, normal or increased bone remodeling states. A consistent group of secondary osteoporosis is related to endocrinological or iatrogenic causes. Exogenous hypercortisolism may be considered an important risk factor for secondary osteoporosis in the community, and probably glucocorticoid-induced osteoporosis is the most common type of secondary osteoporosis. Supraphysiological doses of corticosteroids cause two abnormalities in bone metabolism: a relative increase in bone resorption, and a relative reduction in bone formation. Bone loss, mostly of trabecular bone, with its resultant fractures is the most incapacitating consequence of osteoporosis. The estimated incidence of fractures in patients prescribed corticosteroid is 30% to 50%. Osteoporosis is considered one of the potentially serious side effects of heparin therapy. The occurrence of heparin-induced osteoporosis appeared to be strictly related to the length of treatment (over 4-5 months), and the dosage (15,000 U or more daily), but the pathogenesis is poorly understood. It has been suggested that heparin could cause an increase in bone resorption by increasing the number of differentiated osteoclasts, and by enhancing the activity of individual osteoclasts. Hyperthyroidism is frequently associated with loss of trabecular and cortical bone; the enhanced bone turnover that develops in thyrotoxicosis is characterized by an increase in the number of osteoclasts and resorption sites, and an increase in the ratio of resorptive to formative bone

Lessons learnt from the first EMEP intensive measurement periods

Directory of Open Access Journals (Sweden)

W. Aas

2012-09-01

Full Text Available The first EMEP intensive measurement periods were held in June 2006 and January 2007. The measurements aimed to characterize the aerosol chemical compositions, including the gas/aerosol partitioning of inorganic compounds. The measurement program during these periods included daily or hourly measurements of the secondary inorganic components, with additional measurements of elemental- and organic carbon (EC and OC and mineral dust in PM₁, PM_2.5 and PM₁₀. These measurements have provided extended knowledge regarding the composition of particulate matter and the temporal and spatial variability of PM, as well as an extended database for the assessment of chemical transport models. This paper summarise the first experiences of making use of measurements from the first EMEP intensive measurement periods along with EMEP model results from the updated model version to characterise aerosol composition. We investigated how the PM chemical composition varies between the summer and the winter month and geographically.

The observation and model data are in general agreement regarding the main features of PM₁₀ and PM_2.5 composition and the relative contribution of different components, though the EMEP model tends to give slightly lower estimates of PM₁₀ and PM_2.5 compared to measurements. The intensive measurement data has identified areas where improvements are needed. Hourly concurrent measurements of gaseous and particulate components for the first time facilitated testing of modelled diurnal variability of the gas/aerosol partitioning of nitrogen species. In general, the modelled diurnal cycles of nitrate and ammonium aerosols are in fair agreement with the measurements, but the diurnal variability of ammonia is not well captured. The largest differences between model and observations of aerosol mass are seen in Italy during winter, which to a large extent may be

Common variable immunodeficiency in horses is characterized by B cell depletion in primary and secondary lymphoid tissues.

Science.gov (United States)

Flaminio, M Julia B F; Tallmadge, Rebecca L; Salles-Gomes, Cristina O M; Matychak, Mary Beth

2009-01-01

Common variable immunodeficiency (CVID) in horse patients is characterized by late-onset B cell lymphopenia or depletion, hypo- or agammaglobulinemia, impaired humoral response to tetanus toxoid vaccination, and recurrent fevers and bacterial infections. This study describes the clinical and immunologic findings of 14 affected horses (average age 10.7 +/- 4.4 years) of both genders (six females, eight males) and different breeds (eight Thoroughbreds, four Quarter Horses, one Warmblood, one Pony). Serial immunological testing in peripheral blood revealed persistent, severe B cell lymphopenia (mean 1.3 +/- 2.3% positive cells) in all patients. Serum IgG (range horses. Serum IgA concentrations declined with time. Histopathology and immunohistochemistry revealed absence of lymphoid follicles and B cells in primary and secondary lymphoid tissues. CVID is a cause of recurrent pneumonia, septicemia, and meningitis in adult horses and has a grave prognosis for clinical management and survival.

Is Heart Period Variability Associated with the Administration of Lifesaving Interventions in Individual Prehospital Trauma Patients with Normal Standard Vital Signs?

Science.gov (United States)

2010-08-01

heart period variability as an indicator of mortality in intensive care unit patients many hours before death. Similarly, re- cent studies using data...the Department of Health and Kinesiology (CAR), The University of Texas at San Antonio, San An- tonio, TX; U.S. Army Institute of Surgical Research (CAR

Pulsating red variables

International Nuclear Information System (INIS)

Whitelock, P.A.

1990-01-01

The observational characteristics of pulsating red variables are reviewed with particular emphasis on the Miras. These variables represent the last stage in the evolution of stars on the Asymptotic Giant Branch (AGB). A large fraction of the IRAS sources in the Bulge are Mira variables and a subset of these are also OH/IR sources. Their periods range up to 720 days, though most are between 360 and 560 days. At a given period those stars with the highest pulsation amplitudes have the highest mass-loss rates; this is interpreted as evidence for a causal connection between mass-loss and pulsation. It is suggested that once an AGB star has become a Mira it will evolve with increasing pulsation amplitude and mass-loss, but with very little change of luminosity or logarithmic period. 26 refs

Secondary Physical Education Avoidance and Gender: Problems and Antidotes

Science.gov (United States)

Ryan, Thomas; Poirier, Yves

2012-01-01

Our goal was to locate and evaluate the barriers that impact and cause females to avoid secondary elective physical education courses. We sought to find answers to stop the further decline of female enrolment in secondary physical education by looking into curricula, program and instructional variables. Anecdotal evidence informed this study which…

The Performance of Variable Annuities

OpenAIRE

Michael J. McNamara; Henry R. Oppenheimer

1991-01-01

Variable annuities have become increasingly important in retirement plans. This paper provides an examination of the investment performance of variable annuities for the period year-end 1973 to year-end 1988. Returns, risk, and selectivity measures are analyzed for the sample of annuities, for individual variable annuities, and for subsamples of annuities with similar portfolio size and turnover. While the investment returns of variable annuities were greater than inflation over the period, t...

Perception and Practice of Periodic Medical Checkup by Traders in ...

African Journals Online (AJOL)

Eke CO , Eke NO , Joe-Ikechebelu NN , Okoye. SC. ABSTRACT ... secondary school education and 1.2% had post secondary ... Age, gender and educational status were found not to ... to benefit maximally from periodic medical checkups.

Identification and period investigation of pulsation variable star UY Camelopardalis, an RR Lyrae star in binary system

Science.gov (United States)

Li, Lin-Jia; Qian, Sheng-Bang; Voloshina, Irina; Metlov, Vladimir G.; Zhu, Li-Ying; Liao, Wen-Ping

2018-06-01

We present photometric measurements of the short period variable star UY Cam, which has been classified as a δ Scuti or c-type RR Lyrae (RRc) variable in different catalogs. Based on the analyses on Fourier coefficients and (NUV - V)0, we find that UY Cam is probably an RRc star. We obtain 58 new times of light maximum for UY Cam based on several sky surveys and our observations. Combining these with the times of light maximum in literature, a total of 154 times of light maximum are used to analyze the O - C diagram of UY Cam. The results show that the O - C pattern can be described by a downward parabolic component with a rate of -6.86 ± 0.47 × 10-11 d d-1, and a cyclic variation with a period of 65.7 ± 2.4 yr. We suppose these components are caused by the stellar evolution and the light travel time effect (LiTE) of a companion in elliptical orbit, respectively. By calculation, the minimum mass of the potential companion is about 0.17 M⊙, and its mass should be less than or equal to the pulsation primary star when the inclination i > 22.5°D. Therefore, the companion should be a low-mass star, like a late-type main-sequence star or a white dwarf. Due to the unique property of UY Cam, we suggest that more observations and studies on UY Cam and other RRc stars are needed to check the nature of these stars, including the pulsations and binarities.

APPLE-II type quasi-periodic variably polarizing undulator at HiSOR

International Nuclear Information System (INIS)

Sasaki, Shigemi; Miyamoto, Atsushi; Goto, Kiminori

2012-01-01

A newly constructed quasi-periodic APPLE-II undulator was installed in the HiSOR ring at Hiroshima Synchrotron Radiation Center, Hiroshima University during the summer shutdown period in 2011. This 1.8 m-long undulator has a period length of 78 mm. In this article, the mechanism of magnetic field generation for various polarization modes of APPLE undulator, the principle of quasi-periodic undulator and the performance of HiSOR QP-APPLE-II undulator are described. (author)

The Analysis of the School Burnout in Secondary Education Students in Terms of Various Variables

Directory of Open Access Journals (Sweden)

İsmail Seçer

2012-10-01

Full Text Available In this research, the burnout levels of the secondary education students was analyzed if the burnout levels differentiate according to sex, high school type, academic success, academic department and taking private teaching institutions’ classes or not. The study group of this study that is aimed to analyze school burnout in secondary education students is formed of 282 females and 221 males, in total 503 students who get educated in secondary schools in Erzurum Yakutiye and Palandöken counties. School burnout inventory developed by Aypay (2011 and personal data form were used to collect data. t test and multivariate analysis of variance (MANOVA were used in the analysis of the data.According to the evidence obtained from the study, the burnout levels of secondary education students differentiate in a meaningful level according to sex, school type, academic success, academic department and taking private teaching institutions’ classes or not.

Variability of the total ozone trend over Europe for the period 1950─2004 derived from reconstructed data

Directory of Open Access Journals (Sweden)

J. L. Borkowski

2008-06-01

Full Text Available The total ozone data over Europe are available for only few ground-based stations in the pre-satellite era disallowing examination of the spatial trend variability over the whole continent. A need of having gridded ozone data for a trend analysis and input to radiative transfer models stimulated a reconstruction of the daily ozone values since January 1950. Description of the reconstruction model and its validation were a subject of our previous paper. The data base used was built within the objectives of the COST action 726 "Long-term changes and climatology of UV radiation over Europe". Here we focus on trend analyses. The long-term variability of total ozone is discussed using results of a flexible trend model applied to the reconstructed total ozone data for the period 1950–2004. The trend pattern, which comprises both anthropogenic and "natural" component, is not a priori assumed but it comes from a smooth curve fit to the zonal monthly means and monthly grid values. The ozone long-term changes are calculated separately for cold (October–next year April and warm (May–September seasons. The confidence intervals for the estimated ozone changes are derived by the block bootstrapping. The statistically significant negative trends are found almost over the whole Europe only in the period 1985–1994. Negative trends up to −3% per decade appeared over small areas in earlier periods when the anthropogenic forcing on the ozone layer was weak . The statistically positive trends are found only during warm seasons 1995–2004 over Svalbard archipelago. The reduction of ozone level in 2004 relative to that before the satellite era is not dramatic, i.e., up to ~−5% and ~−3.5% in the cold and warm subperiod, respectively. Present ozone level is still depleted over many popular resorts in southern Europe and northern Africa. For high latitude regions the trend overturning could be inferred in last decade (1995–2004 as the ozone depleted

Seasonal precipitation extreme indices in mainland Portugal: trends and variability in the period 1941-2007

Science.gov (United States)

Santo, Fátima E.; Ramos, Alexandre M.; de Lima, M. Isabel P.; Trigo, Ricardo M.

2013-04-01

Changes in the precipitation regimes are expected to be accompanied by variations in the occurrence of extreme events, which in turn could be related to low frequency variability. The impact on the society and environment requires that the regional specificities are understood. For mainland Portugal, this work reports the results of the analysis of trends in selected precipitation indices calculated from daily precipitation data from 57 meteorological stations, recorded in the period 1941-2007; additionally we have also investigated the correlations between these indices and several modes of low frequency variability over the area. We focus on exploring regional differences and seasonal variations in the intensity, frequency and duration of extreme precipitation events. The precipitation indices were assessed at the seasonal scale and calculated at both the station and regional scales. Results sometimes highlight marked changes in seasonal precipitation and show that: i) trends in spring and autumn have opposite signals: statistically significant drying trends in the spring are accompanied by a reduction in precipitation extremes; in autumn, wetting trends are detected for all precipitation indices, although overall they are not significant at the 5% level; ii) there seems to be a tendency for a reduction in the duration of the rainy season; iii) the North Atlantic Oscillation (NAO) is the mode of variability that has the highest influence on precipitation extremes over mainland Portugal, particularly in the winter and autumn, and is one of the most important teleconnection patterns in all seasons. This work was partially supported by FEDER (Fundo Europeu de Desenvolvimento Regional) funds through the COMPETE (Programa Operacional Factores de Competitividade) and by national funds through FCT (Fundação para a Ciência e a Tecnologia, Portugal) through project STORMEx FCOMP-01-0124-FEDER-019524 (PTDC/AAC-CLI/121339/2010).

Variability and quasi-decadal changes in the methane budget over the period 2000-2012

Science.gov (United States)

Saunois, Marielle; Bousquet, Philippe; Poulter, Ben; Peregon, Anna; Ciais, Philippe; Canadell, Josep G.; Dlugokencky, Edward J.; Etiope, Giuseppe; Bastviken, David; Houweling, Sander; Janssens-Maenhout, Greet; Tubiello, Francesco N.; Castaldi, Simona; Jackson, Robert B.; Alexe, Mihai; Arora, Vivek K.; Beerling, David J.; Bergamaschi, Peter; Blake, Donald R.; Brailsford, Gordon; Bruhwiler, Lori; Crevoisier, Cyril; Crill, Patrick; Covey, Kristofer; Frankenberg, Christian; Gedney, Nicola; Höglund-Isaksson, Lena; Ishizawa, Misa; Ito, Akihiko; Joos, Fortunat; Kim, Heon-Sook; Kleinen, Thomas; Krummel, Paul; Lamarque, Jean-François; Langenfelds, Ray; Locatelli, Robin; Machida, Toshinobu; Maksyutov, Shamil; Melton, Joe R.; Morino, Isamu; Naik, Vaishali; O'Doherty, Simon; Parmentier, Frans-Jan W.; Patra, Prabir K.; Peng, Changhui; Peng, Shushi; Peters, Glen P.; Pison, Isabelle; Prinn, Ronald; Ramonet, Michel; Riley, William J.; Saito, Makoto; Santini, Monia; Schroeder, Ronny; Simpson, Isobel J.; Spahni, Renato; Takizawa, Atsushi; Thornton, Brett F.; Tian, Hanqin; Tohjima, Yasunori; Viovy, Nicolas; Voulgarakis, Apostolos; Weiss, Ray; Wilton, David J.; Wiltshire, Andy; Worthy, Doug; Wunch, Debra; Xu, Xiyan; Yoshida, Yukio; Zhang, Bowen; Zhang, Zhen; Zhu, Qiuan

2017-09-01

Following the recent Global Carbon Project (GCP) synthesis of the decadal methane (CH4) budget over 2000-2012 (Saunois et al., 2016), we analyse here the same dataset with a focus on quasi-decadal and inter-annual variability in CH4 emissions. The GCP dataset integrates results from top-down studies (exploiting atmospheric observations within an atmospheric inverse-modelling framework) and bottom-up models (including process-based models for estimating land surface emissions and atmospheric chemistry), inventories of anthropogenic emissions, and data-driven approaches. The annual global methane emissions from top-down studies, which by construction match the observed methane growth rate within their uncertainties, all show an increase in total methane emissions over the period 2000-2012, but this increase is not linear over the 13 years. Despite differences between individual studies, the mean emission anomaly of the top-down ensemble shows no significant trend in total methane emissions over the period 2000-2006, during the plateau of atmospheric methane mole fractions, and also over the period 2008-2012, during the renewed atmospheric methane increase. However, the top-down ensemble mean produces an emission shift between 2006 and 2008, leading to 22 [16-32] Tg CH4 yr-1 higher methane emissions over the period 2008-2012 compared to 2002-2006. This emission increase mostly originated from the tropics, with a smaller contribution from mid-latitudes and no significant change from boreal regions. The regional contributions remain uncertain in top-down studies. Tropical South America and South and East Asia seem to contribute the most to the emission increase in the tropics. However, these two regions have only limited atmospheric measurements and remain therefore poorly constrained. The sectorial partitioning of this emission increase between the periods 2002-2006 and 2008-2012 differs from one atmospheric inversion study to another. However, all top-down studies

Northern Hemisphere moisture variability during the Last Glacial period

Science.gov (United States)

Asmerom, Y.; Polyak, V. J.; Lachniet, M. S.

2013-12-01

It was previously shown that large oxygen isotope variability related to changing moisture sources in the southwestern United States (SW) match the Greenland ice core temperature record. The variations were attributed to changes in the ratio of winter to summer precipitation delivered to the SW, with lighter winter δ18O values compared to summer monsoon rainfall, due to meridonial shifts in the position of the polar jet stream, which directs winter storm tracks. Cold stadial δ18O excursions are associated with strongly negative values, while interstadials have higher than average δ18O values. Although these data documented moisture source variability to the SW, the question of effective moisture variability remains unanswered. Here we present new high-resolution δ18O and δ13C isotopic data from a precisely dated speleothem, FS-AH1, from Fort Stanton Cave, New Mexico USA. The sample grew continuously between 47.6 and 11.1 kyr. The new chronology is more precise than previous work due to high sample growth rate, new gains in efficiency provided by our upgraded Neptune MC-ICPMS and new more precise determinations of the half-lives of 230Th and 234U. The FS-AH1 δ18O and the Greenland δ18O data (on the GICC05 time scale) show a remarkable match, both with respect to stadials/interstadial amplitudes and variability, and in the overall long-term trend. Our interpretation of the δ18O data remains the same, an indicator of moisture source variability. The δ18O and δ13C isotopic data show no correlation (R2 effective moisture in the soil zone overlying the cave, with low δ13C attributed to high soil productivity, high effective moisture, and wet conditions. The stadial and interstadial events are expressed mutely, if at all, in the δ13C data, while the secular variation follows the change in Northern Hemisphere summer insolation (insolation), similar to other Northern Hemisphere data, such as the strength of the East Asian summer monsoon as recorded in the Hulu

Light Curve Periodic Variability of Cyg X-1 using Jurkevich Method

Indian Academy of Sciences (India)

The Jurkevich method is a useful method to explore periodicity in the unevenly sampled observational data. In this work, we adopted the method to the light curve of Cyg X-1 from 1996 to 2012, and found that there is an interesting period of 370 days, which appears in both low/hard and high/soft states. That period may be ...

EFEKTIFITAS MEKANISME TRANSMISI KEBIJAKAN MONETER PADA JALUR SUKU BUNGA PERIODE 2005:07-2010:06

Directory of Open Access Journals (Sweden)

Muhammad Alfian

2017-11-01

Full Text Available Vector Auto Regression (VAR is an analysis or statistic method which can be used to predict time series variable and to analyst dynamic impact of disturbance factor in the variable system. In addition, VAR analysis is very usefull to assess the interrelationship between economics variable. This research through the following test phases: unit root test, optimal lag test, granger causality test, and form a vector auto regression model (VAR. The data used in this research is the Bank Indonesia Certificate rate data (SBI, interbank offered rate data (PUAB, deposit rate data (DEP, loan rate data (KDRT and credit aggregate data (AGKDRT of Indonesia in the period 2005:07-2010:06. The effectiveness was measured by two indicators. They are: (1. how fast or how many time lag needed since the shock of monetary instruments (rSBI until the realisation of intermediary target of monetary policy (monetary aggregate. (2. How strong the variables of Interest Rate Channel response the shock of SBI interest rate and other variable. This study used secondary data issued by Bank Indonesia. The result of the study shows that response velocity of variable in Interest Rate Channel towards shock instrument of monetary policy (SBI until reach the final target about 4 months. While impulse response function of variables in this channel to the shock instrument of monetary policy (SBI is quiet weak and the main variable in interest rate money market among bank (PUAB able to explain diversity intermediary target of monetary policy (Monetary Aggregate about 2,82%. This result once shows a weak Granger causality and predictive power between PUAB as the operational target with monetary aggregate as the intermediary target of monetary policy. Thus we can conclude that mechanism of monetary policy transmission through Interest Rate Channel is not effective to reach the intermediary target of monetary policy of Indonesia period of 2005:072010:06. Keyword: Vector Auto Regression

RADIO MONITORING OF THE PERIODICALLY VARIABLE IR SOURCE LRLL 54361: NO DIRECT CORRELATION BETWEEN THE RADIO AND IR EMISSIONS

Energy Technology Data Exchange (ETDEWEB)

Forbrich, Jan, E-mail: jan.forbrich@univie.ac.at [University of Vienna, Department of Astrophysics, Türkenschanzstraße 17, A-1180 Vienna (Austria); Rodríguez, Luis F.; Palau, Aina; Zapata, Luis A. [Instituto de Radioastronomía y Astrofísica, UNAM, Apdo. Postal 3-72 (Xangari), 58089 Morelia, Michoacán (Mexico); Muzerolle, James [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Gutermuth, Robert A. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States)

2015-11-20

LRLL 54361 is an infrared source located in the star-forming region IC 348 SW. Remarkably, its infrared luminosity increases by a factor of 10 over roughly one week every 25.34 days. To understand the origin of these remarkable periodic variations, we obtained sensitive 3.3 cm JVLA radio continuum observations of LRLL 54361 and its surroundings in six different epochs: three of them during the IR-on state and three during the IR-off state. The radio source associated with LRLL 54361 remained steady and did not show a correlation with the IR variations. We suggest that the IR is tracing the results of fast (with a timescale of days) pulsed accretion from an unseen binary companion, while the radio traces an ionized outflow with an extent of ∼100 AU that smooths out the variability over a period of the order of a year. The average flux density measured in these 2014 observations, 27 ± 5 μJy, is about a factor of two less than that measured about 1.5 years before, 53 ± 11 μJy, suggesting that variability in the radio is present, but over larger timescales than in the IR. We discuss other sources in the field, in particular two infrared/X-ray stars that show rapidly varying gyrosynchrotron emission.

Irrational antibiotic usage in boarding secondary school settings in ...

African Journals Online (AJOL)

Objective: To assess the prevalence of antibiotic misuse among boarding secondary school students in Dar es Salaam. Methodology: This descriptive cross-sectional study was conducted over 3-month period amongst boarding secondary school students. A randomized sample of students was recruited from at least 3 ...

Discrete rate and variable power adaptation for underlay cognitive networks

KAUST Repository

Abdallah, Mohamed M.; Salem, Ahmed H.; Alouini, Mohamed-Slim; Qaraqe, Khalid A.

2010-01-01

We consider the problem of maximizing the average spectral efficiency of a secondary link in underlay cognitive networks. In particular, we consider the network setting whereby the secondary transmitter employs discrete rate and variable power

The writing approaches of secondary students.

Science.gov (United States)

Lavelle, Ellen; Smith, Jennifer; O'Ryan, Leslie

2002-09-01

Research with college students has supported a model of writing approaches that defines the relationship between a writer and writing task along a deep and surface process continuum (Biggs, 1988). Based on that model, Lavelle (1993) developed the Inventory of Processes in College Composition which reflects students' motives and strategies as related to writing outcomes. It is also important to define the approaches of secondary students to better understand writing processes at that level, and development in written composition. This study was designed to define the writing approaches of secondary students by factor analysing students' responses to items regarding writing beliefs and writing strategies, and to compare the secondary approaches to those of college students. A related goal was to explore the relationships of the secondary writing approaches to perceived self-regulatory efficacy for writing (Zimmerman & Bandura, 1994), writing preferences, and writing outcomes. The initial, factor analytic phase involved 398 junior level high school students (11th grade) enrolled in a mandatory language arts class at each of three large Midwestern high schools (USA). Then, 49 junior level students enrolled in two language arts classes participated as subjects in the second phase. Classroom teachers administered the Inventory of Processes in College Composition (Lavelle, 1993), which contained 72 true-or-false items regarding writing beliefs and strategies, during regular class periods. Data were factor analysed and the structure compared to that of college students. In the second phase, the new inventory, Inventory of Processes in Secondary Composition, was administered in conjunction with the Perceived Self-Regulatory Efficacy for Writing Inventory (Zimmerman & Bandura, 1994), and a writing preferences survey. A writing sample and grade in Language Arts classes were obtained and served as outcome variables. The factor structure of secondary writing reflected three

Allochronic speciation, secondary contact, and reproductive character displacement in periodical cicadas (Hemiptera: Magicicada spp.): genetic, morphological, and behavioural evidence.

Science.gov (United States)

Cooley, J R; Simon, C; Marshall, D C; Slon, K; Ehrhardt, C

2001-03-01

Periodical cicadas have proven useful in testing a variety of ecological and evolutionary hypotheses because of their unusual life history, extraordinary abundance, and wide geographical range. Periodical cicadas provide the best examples of synchronous periodicity and predator satiation in the animal kingdom, and are excellent illustrations of habitat partitioning (by the three morphologically distinct species groups), incipient species (the year classes or broods), and cryptic species (a newly discovered 13-year species, Magicicada neotredecim). They are particularly useful for exploring questions regarding speciation via temporal isolation, or allochronic speciation. Recently, data were presented that provided strong support for an instance of allochronic speciation by life-cycle switching. This speciation event resulted in the formation of a new 13-year species from a 17-year species and led to secondary contact between two formerly separated lineages, one represented by the new 13-year cicadas (and their 17-year ancestors), and the other represented by the pre-existing 13-year cicadas. Allozyme frequency data, mitochondrial DNA (mtDNA), and abdominal colour were shown to be correlated genetic markers supporting the life-cycle switching/allochronic speciation hypothesis. In addition, a striking pattern of reproductive character displacement in male call pitch and female pitch preference between the two 13-year species was discovered. In this paper we report a strong association between calling song pitch and mtDNA haplotype for 101 individuals from a single locality within the M. tredecim/M. neotredecim contact zone and a strong association between abdomen colour and mtDNA haplotype. We conclude by reviewing proposed mechanisms for allochronic speciation and reproductive character displacement.

[The variability of vegetation beginning date of greenness period in spring in the north-south transect of eastern China based on NOAA NDVI].

Science.gov (United States)

Wang, Zhi; Liu, Shi-rong; Sun, Peng-sen; Guo, Zhi-hua; Zhou, Lian-di

2010-10-01

NDVI based on NOAA/AVHRR from 1982 to 2003 are used to monitor variable rules for the growing season in spring of vegetation in the north-south transect of eastern China (NSTEC). The following, mainly, are included: (1) The changing speed of greenness period in spring of most regions in NSTEC is slow and correlation with the year is not distinct; (2) The regions in which greenness period in spring distinctly change mainly presented an advance; (3) The regions in which inter-annual fluctuation of greenness period in spring is over 10 days were found in 3 kinds of areas: the area covered with agricultural vegetation types; the areas covered with evergreen vegetation types; the areas covered with steppe vegetation types; (4) changes of vegetation greenness period in spring have spatio-temporal patterns.

Cosmogenic nuclide production within the atmosphere and long period comets

Science.gov (United States)

Overholt, Andrew C.

The Earth is constantly bombarded by cosmic rays. These high energy particles collide with target nuclei, producing a shower of secondary particles. These secondaries contribute significantly to the radiation background at sea level and in the atmosphere, as well as producing rare cosmogenic nuclides. This contribution is variable over long time scales as astrophysical events change the cosmic ray flux incident on the Earth. Our work re-examines a previously proposed climate effect of increased cosmic ray flux due to galactic location. Although our work does not support this effect, cosmic ray secondaries remain a threat to terrestrial biota. We calculate the cosmogenic neutron flux within the atmosphere as a function of primary spectrum. This work is pivotal in determining the radiation dose due to any arbitrary astrophysical event where the primary spectrum is known. Additionally, this work can be used to determine the cosmogenic nuclide production from such an event. These neutrons are the fundamental source of cosmogenic nuclides within our atmosphere and extraterrestrial matter. We explore the idea that excursions in 14C and 10Be abundances in the atmosphere may arise from direct deposition by long-period comet impacts, and those in 26Al from any bolide. We find that the amount of nuclide mass on large long-period comets entering the Earth's atmosphere may be sufficient for creating anomalies in the records of 14C and 10Be from past impacts. In particular, the estimated mass of the proposed Younger Dryas comet is consistent with its having deposited sufficient isotopes to account for recorded nuclide increases at that time. The 26Al/10Be ratio is much larger in extraterrestrial objects than in the atmosphere, and so, we note that measuring this ratio in ice cores is a suitable further test for the Younger Dryas impact hypothesis. This portion of our work may be used to find possible impact events in the geologic record as well as determination of a large

A Study of the Kepler K2 Variable EPIC 211957146 Exhibiting a Variable O’ Connell Effect

International Nuclear Information System (INIS)

Sriram, K.; Malu, S.; Rao, P. Vivekananda; Choi, C. S.

2017-01-01

We present the multi-band photometric and spectroscopic study of an over-contact binary system, EPIC 211957146. The light curves exhibit a variable O’ Connell effect, confirmed from our observational data and the Kepler K2 data. The best photometric solution incorporating a dark spot over the primary component unveils that the system has a low-mass ratio ( q  ∼ 0.17) and a high inclination ( i  ∼ 85°). To confirm the solution and constrain the uncertainty, Monte-Carlo simulations are performed and the results are reported. Based on the O–C diagram analysis, we see that the variable shows a period increase at the rate of dP / dt  ∼ 1.06 × 10 −6 days yr −1 , which is higher than the theoretically predicted value. Presence of a third body having a period of ∼16.23 years is evident from the O–C diagram. No filled-in effect is observed in the H α line, while the effect is vividly present in the Na line. From the Kepler K2 data, we found that the primary and secondary minima exhibit an anti-correlated O–C variation followed by an erratic behavior. This is possibly caused by the longitudinal motion of the spot, and hence, we set a lower limit of ∼40 days for the spot modulation. We also observe a possibly associated photometric difference in the primary depth by comparing our light curves with Kepler K2 normalized light curves. This system has a low-mass ratio and a high fill-out factor, and, theoretically, such a physical configuration would lead to a merger.

Rapid oscillations in cataclysmic variables. VI. Periodicities in erupting dwarf novae

International Nuclear Information System (INIS)

Patterson, J.

1981-01-01

We report an extensive study of the coherent oscillations observed in high-speed photometry of dwarf novae during eruption. The oscillations are in all cases singly periodic and sinusoidal to the limits of measurement. The detection of oscillations in 14 separate eruptions of AH Her and SY Cnc enables a general study of period variations. The stars trace out characteristic loops (''banana diagrams'') in the period-intensity plane. New detections are also reported for SS Cyg, EM Cyg, and HT Cas

Period Changes of 23 Field RR Lyrae Stars

Directory of Open Access Journals (Sweden)

Soo-Chang Rey

1994-12-01

Full Text Available The secular period behavior of 23 field RR Lyrae stars is studied in order to determine if the observed period changes could be attributed, at least in the mean, to stellar evolution. The sample of stars is subdivided into two Oosterhoff groups based on the metallicity and period-shift. Despite the small sample size, we found a distinct bias toward positive period changes in the group variables. The period changes of the group variables in globular clusters. This provides yet another support for the Lee, Demarque, and Zinn(1990 evolutionary models of RR Lyrae stars and their explanation of the Sandage period-shift effect.

Corot 310266512: A Light Curve With Primary, Secondary And Tertiary Eclipses

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Fernández Fernández Javier

2015-01-01

Full Text Available We present the photometric study of an interesting target in the CoRoT exoplanet database: CoRoT 310266512. Its light curve shows primary, secondary and tertiary eclipses that suggests the presence of at least three celestial bodies. The primary and secondary eclipses have the same orbital period, 7.42 days, and the tertiary eclipse has an orbital period of 3.27 days. Two of the tertiary eclipses fall within a primary eclipse and a secondary eclipse. The properties of the light curve indicate the presence of two physically separated systems. The primary and secondary eclipses corresponds to a binary system (System I. The tertiary eclipses correspond to a star-planet system or a star-dwarf system (System II. Some parameters of these two systems are obtained from JKTEBOP [1] program.

Steady Secondary Flows Generated by Periodic Compression and Expansion of an Ideal Gas in a Pulse Tube

Science.gov (United States)

Lee, Jeffrey M.

1999-01-01

This study establishes a consistent set of differential equations for use in describing the steady secondary flows generated by periodic compression and expansion of an ideal gas in pulse tubes. Also considered is heat transfer between the gas and the tube wall of finite thickness. A small-amplitude series expansion solution in the inverse Strouhal number is proposed for the two-dimensional axisymmetric mass, momentum and energy equations. The anelastic approach applies when shock and acoustic energies are small compared with the energy needed to compress and expand the gas. An analytic solution to the ordered series is obtained in the strong temperature limit where the zeroth-order temperature is constant. The solution shows steady velocities increase linearly for small Valensi number and can be of order I for large Valensi number. A conversion of steady work flow to heat flow occurs whenever temperature, velocity or phase angle gradients are present. Steady enthalpy flow is reduced by heat transfer and is scaled by the Prandtl times Valensi numbers. Particle velocities from a smoke-wire experiment were compared with predictions for the basic and orifice pulse tube configurations. The theory accurately predicted the observed steady streaming.

Effects of peer education intervention on HIV/AIDS related sexual behaviors of secondary school students in Addis Ababa, Ethiopia: a quasi-experimental study.

Science.gov (United States)

Menna, Takele; Ali, Ahmed; Worku, Alemayehu

2015-09-07

Worldwide, about 50% of all new cases of HIV occur in youth between age 15 and 24 years. Studies in various sub-Saharan African countries show that both out of school and in school adolescents and youth are engaged in risky sexual behaviors. School-based health education has been a cornerstone of youth-focused HIV prevention efforts since the early 1990s. In addition, peer-based interventions have become a common method to effect important health-related behavior changes and address the HIV/AIDS pandemic. Thus, the aim of this study was to evaluate efficacy of peer education on changing HIV related risky sexual behaviors among school youth in Addis Ababa, Ethiopia. A quasi experimental study with peer education intervention was conducted in purposively selected four secondary schools (two secondary schools for the intervention and other two for the control group) in Addis Ababa, Ethiopia. Five hundred sixty students from randomly selected sections of grade 11 were assessed through anonymous questionnaires conducted in pre- and post-intervention periods. Pertinent data on socio-demographic and sexual behavior related factors were collected. The statistical packages used for data entry and analysis were epi-info version 3.5.4 and SPSS version 20.0 respectively. Chi-square test and multivariable logistic regressions were used for testing association between peer education intervention and sexual behaviors of students. In addition to testing association between dependent and independent variables, multi-variable analysis was employed to control for the effects of confounding variables. When the pre and post intervention data of each group were compared, comprehensive Knowledge of HIV (P-Values =0.004) and willingness to go for HIV counseling and testing (P-value = 0.01) showed significant differences among intervention group students during post intervention period. Moreover, students in the intervention group were more likely to use condoms during post

Environmental radiation monitoring results for the period 1984-95 in and around Variable Energy Cyclotron Centre, Calcutta

International Nuclear Information System (INIS)

Basu, A.S.; Khasnabis, B.K.; Bar, M.

1997-04-01

Variable Energy Cyclotron (VEC) located at Bidhan Nagar, Calcutta is being used for accelerating charged particles and does not contribute to any radioactive releases to the environment. However, it being a nuclear facility, the area surrounding the facility is being routinely monitored for background radiation exposure using thermoluminescent dosimeters. This report gives the summary of the results of the survey carried out over a period of 12 years, 1984-1995. It is observed that the general radiation background in areas far removed from the facility (up to 25 km) is higher than that existing within the boundaries of VEC centre (160±21 mR/year as against 121±20 mR/year)

Thyrotoxic periodic paralysis

Directory of Open Access Journals (Sweden)

Rojith Karandode Balakrishnan

2011-01-01

Full Text Available This article aims at highlighting the importance of suspecting thyrotoxicosis in cases of recurrent periodic flaccid paralysis; especially in Asian men to facilitate early diagnosis of the former condition. A case report of a 28 year old male patient with recurrent periodic flaccid paralysis has been presented. Hypokalemia secondary to thyrotoxicosis was diagnosed as the cause of the paralysis. The patient was given oral potassium intervention over 24 hours. The patient showed complete recovery after the medical intervention and was discharged after 24 hours with no residual paralysis. Thyrotoxic periodic paralysis (TPP is a complication of thyrotoxicosis, more common amongst males in Asia. It presents as acute flaccid paralysis in a case of hyperthyroidism with associated hypokalemia. The features of thyrotoxicosis may be subtle or absent. Thus, in cases of recurrent or acute flaccid muscle paralysis, it is important to consider thyrotoxicosis as one of the possible causes, and take measures accordingly.

Light curve solutions and out-of-eclipse variability of KIC 10031409, KIC 11228612, KIC 11403216 and KIC 11913071

Directory of Open Access Journals (Sweden)

Kjurkchieva D.

2017-01-01

Full Text Available We carried out light curve solutions of four detached binaries observed by Kepler. As a result, their orbital inclinations, temperatures and relative stellar radii were determined. KIC 10031409 and KIC 11228612 reveal partial eclipses while the components of KIC 11403216 and KIC 11913071 undergo total eclipses. The secondary component of KIC 11403216 is probably a very late M dwarf or brown dwarf. The out-of-eclipse brightness of KIC 10031409, KIC 11228612 and KIC 11913071 vary with the orbital period and might be explained by spots on synchronously-rotating star(s. The out-of-eclipse variability of KIC 11403216 is with a period that is a third of its orbital period and may be due to spot on asynchronous rotating component. The resonance 1:3 needs future study of KIC 11403216.

Genetic variability of the whitefly Bemisia tabaci and its secondary endosymbionts in the Arabian Peninsula

KAUST Repository

Ragab, Alaa I.

2013-05-01

The whitefly Bemisia tabaci species complex has been well documented as one of the most economically important emergent plant virus vectors, through serious feeding damage to its broad range of plant hosts and transmission of plant viruses to important agricultural crops. It has been shown to have associations with endosymbionts which have significant effects on the insect fitness. The purpose of this study was to provide information for the biotype and secondary endosymbiont distribution for B. tabaci populations in the relatively unstudied Arabian peninsula. The geographical localization and variation in endosymbiont populations across the region were identified using a sequence-driven analysis of the population genetics of the secondary endosymbiont. Live field specimens were collected from 22 different locations in the region and preserved in 70% ethanol for genetic studies. Previously established procedures were used to extract and purify total insect DNA from 24-30 individual whiteflies for each location (Frohlich et al., 1999; Chiel et al., 2007). Specimens were subjected to PCR amplification using the respective 16S rDNAprimers for the Rickettsia, Hamiltonella, and Wolbachia to amplify endosymbiont DNA. PCR was run with primers for the highly conserved whitefly mitochondrial cytochrome oxidase subunit I (COI) gene for biotyping. Samples were sequenced using the Sanger method and the data analyzed to correlate the presence, prevalence and geographical distribution of endosymbionts in B. tabaci. Phylogenies 5 were constructed to track evolutionary differences amongst the endosymbionts and insects and how they have influenced the evolution of the regional populations. Samples were characterized by differences in the genomes and endosymbionts of common whitefly ‘biotypes’ that have different host plant preferences, vector capacities and insecticide resistance characteristics. It was found that the B biotype is the predominant haplotype, with no evidence of

Variability of Atmospheric Radon-222 and Secondary Aerosol Components in Accordance with Air Mass Transport Pathways at Jeju Island, Korea, during 2011-2014

International Nuclear Information System (INIS)

Bu, Jun-Oh; Song, Jung-Min; Kim, Won-Hyung; Kang, Chang-Hee; Chambers, Scott D.; Williams, Alastair G.; Lee, Chulkyu

2016-01-01

Real-time monitoring of hourly atmospheric Radon-222 concentration and three daily monitoring of the secondary aerosol components of PM_1_0 were performed throughout 2011-2014 at Gosan station, Jeju Island, in order to characterize their background levels and temporal variation. The annual mean radon and PM_1_0 mass concentrations were 2326 ± 1198 mBq/m"3 and 37.1 ± 19.5 μg/m"3, respectively. Based on cluster analyses of air mass back trajectories, the frequencies of air masses originating from continental China, the Korean Peninsula, and North Pacific Ocean routes were 53, 28, and 19%, respectively. When the air masses were transported to Jeju Island from continental China, the concentrations of radon and secondary aerosol components (nss-SO_4"2"-, NO_3"-, NH_4"+) were relatively high: 2577 mBq/m"3 and 14.4 μg/m"3, respectively. In cases when the air masses have moved from the Korean Peninsula, the corresponding concentrations were 2247 mBq/m"3 and 11.4 μg/m"3, respectively. On the other hand, when the air masses came from the North Pacific Ocean, their radon and secondary aerosol concentrations decreased much further, 1372 mBq/m"3 and 10.5 μg/m"3, respectively. Consequently, the variability of atmospheric radon concentrations at Gosan station might be characterized by synoptic changes in air mass fetch as well as diurnal changes in atmospheric mixing depth.

Astrometry with Hubble Space Telescope Fine Guidance Sensor 3: The Parallax of the Cataclysmic Variable RW Triangulum

Science.gov (United States)

McArthur, B. E.; Benedict, G. F.; Lee, J.; Lu, C.-L.; van Altena, W. F.; Deliyannis, C. P.; Girard, T.; Fredrick, L. W.; Nelan, E.; Duncombe, R. L.; Hemenway, P. D.; Jefferys, W. H.; Shelus, P. J.; Franz, O. G.; Wasserman, L. H.

1999-07-01

RW Triangulum (RW Tri) is a 13th magnitude nova-like cataclysmic variable star with an orbital period of 0.2319 days (5.56 hr). Infrared observations of RW Tri indicate that its secondary is most likely a late-K dwarf (Dhillon). Past analyses predicted a distance of 270 pc, derived from a blackbody fit to the spectrum of the central part of the disk (Rutten, van Paradijs, & Tinbergen). Recently completed Hubble Space Telescope Fine Guidance Sensor interferometric observations allow us to determine the first trigonometric parallax to RW Tri. This determination puts the distance of RW Tri at 341-31+38, one of the most distant objects with a direct parallax measurement. We compare our result with methods previously employed to estimate distances to cataclysmic variables.

Variability of cannabis potency in the Venice area (Italy): a survey over the period 2010-2012.

Science.gov (United States)

Zamengo, Luca; Frison, Giampietro; Bettin, Chiara; Sciarrone, Rocco

2014-01-01

Cannabis is the most widely used illicit substance globally, with an estimated annual prevalence in 2010 of 2.6-5.0% of the adult population. Concerns have been expressed about increases in the potency of cannabis products. A high tetrahydrocannabinol (THC) content can increase anxiety, depression, and psychotic symptoms, and can increase the risk of dependence and adverse effects on the respiratory and cardiovascular systems in regular users. The aim of this study was to report statistical data about the potency of cannabis products seized in the north-east of Italy, in a geographical area centred in Venice and extending for more than 10,000  km(2) with a population of more than two million, by investigating the variability observed in THC levels of about 4000 samples of cannabis products analyzed over the period 2010-2012. Overall median THC content showed an increasing trend over the study period from about 6.0% to 8.1% (6.2-8.9% for cannabis resin, 5.1-7.6% for herbal cannabis). The variation in the THC content of individual samples was very large, ranging from 0.3% to 31% for cannabis resin and from 0.1 to 19% for herbal cannabis. Median CBN:THC ratios showed a slightly decreasing trend over the study period, from 0.09 (2010) to 0.03 (2012), suggesting an increasing freshness of submitted materials. Median CBD:THC ratios also showed a decreasing trend over the study from about 0.52 (2010) to 0.18 (2012), likely due to the increase in submissions of materials from indoor and domestic cultivation with improved breeding methods. Copyright © 2013 John Wiley & Sons, Ltd.

Adolescent low back pain among secondary school students in ...

African Journals Online (AJOL)

ary school students in Ibadan, Nigeria and the prevalence's association with some socio-demographic variables. Methods: Participants were adolescent students from 15 secondary schools in Ibadan. Data was ..... Applied Ergonomics 1987;.

Variability and quasi-decadal changes in the methane budget over the period 2000–2012

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M. Saunois

2017-09-01

Full Text Available Following the recent Global Carbon Project (GCP synthesis of the decadal methane (CH4 budget over 2000–2012 (Saunois et al., 2016, we analyse here the same dataset with a focus on quasi-decadal and inter-annual variability in CH4 emissions. The GCP dataset integrates results from top-down studies (exploiting atmospheric observations within an atmospheric inverse-modelling framework and bottom-up models (including process-based models for estimating land surface emissions and atmospheric chemistry, inventories of anthropogenic emissions, and data-driven approaches. The annual global methane emissions from top-down studies, which by construction match the observed methane growth rate within their uncertainties, all show an increase in total methane emissions over the period 2000–2012, but this increase is not linear over the 13 years. Despite differences between individual studies, the mean emission anomaly of the top-down ensemble shows no significant trend in total methane emissions over the period 2000–2006, during the plateau of atmospheric methane mole fractions, and also over the period 2008–2012, during the renewed atmospheric methane increase. However, the top-down ensemble mean produces an emission shift between 2006 and 2008, leading to 22 [16–32] Tg CH4 yr−1 higher methane emissions over the period 2008–2012 compared to 2002–2006. This emission increase mostly originated from the tropics, with a smaller contribution from mid-latitudes and no significant change from boreal regions. The regional contributions remain uncertain in top-down studies. Tropical South America and South and East Asia seem to contribute the most to the emission increase in the tropics. However, these two regions have only limited atmospheric measurements and remain therefore poorly constrained. The sectorial partitioning of this emission increase between the periods 2002–2006 and 2008–2012 differs from one atmospheric inversion study to

Photometry of the long period dwarf nova GY Hya

Science.gov (United States)

Bruch, Albert; Monard, Berto

2017-08-01

Although comparatively bright, the cataclysmic variable GY Hya has not attracted much attention in the past. As part of a project to better characterize such systems photometrically, we observed light curves in white light, each spanning several hours, at Bronberg Observatory, South Africa, in 2004 and 2005, and at the Observatório do Pico dos Dias, Brazil, in 2014 and 2016. These data permit to study orbital modulations and their variations from season to season. The orbital period, already known from spectroscopic observations of Peters and Thorstensen (2005), is confirmed through strong ellipsoidal variations of the mass donor star in the system and the presence of eclipses of both components. A refined period of 0.34723972 (6) days and revised ephemeries are derived. Seasonal changes in the average orbital light curve can qualitatively be explained by variations of the contribution of a hot spot to the system light together with changes of the disk radius. The amplitude of the ellipsoidal variations and the eclipse contact phases permit to put some constraints on the mass ratio, orbital inclination and the relative brightness of the primary and secondary components. There are some indications that the disk radius during quiescence, expressed in units of the component separation, is smaller than in other dwarf novae.

Tides and Decadal Variability

Science.gov (United States)

Ray, Richard D.

2003-01-01

This paper reviews the mechanisms by which oceanic tides and decadal variability in the oceans are connected. We distinguish between variability caused by tides and variability observed in the tides themselves. Both effects have been detected at some level. The most obvious connection with decadal timescales is through the 18.6-year precession of the moon's orbit plane. This precession gives rise to a small tide of the same period and to 18.6-year modulations in the phase and amplitudes of short-period tides. The 18.6-year "node tide" is very small, no more than 2 cm anywhere, and in sea level data it is dominated by the ocean's natural Variability. Some authors have naively attributed climate variations with periods near 19 years directly to the node tide, but the amplitude of the tide is too small for this mechanism to be operative. The more likely explanation (Loder and Garrett, JGR, 83, 1967-70, 1978) is that the 18.6-y modulations in short-period tides, especially h e principal tide M2, cause variations in ocean mixing, which is then observed in temperature and other climatic indicators. Tidally forced variability has also been proposed by some authors, either in response to occasional (and highly predictable) tidal extremes or as a nonlinear low-frequency oscillation caused by interactions between short-period tides. The former mechanism can produce only short-duration events hardly more significant than normal tidal ranges, but the latter mechanism can in principle induce low-frequency oscillations. The most recent proposal of this type is by Keeling and Whorf, who highlight the 1800-year spectral peak discovered by Bond et al. (1997). But the proposal appears contrived and should be considered, in the words of Munk et al. (2002), "as the most likely among unlikely candidates."

Further Results on Extended Delivery Time for Secondary Packet Transmission

KAUST Repository

Usman, Muneer; Yang, Hong-Chuan; Alouini, Mohamed-Slim

2017-01-01

with non-work-preserving strategy, where interrupted packets must be repeated. We also analyze the effect of imperfect periodic sensing, i.e., the secondary user periodically senses the spectrum for availability, with a chance of missing an available

The Relationship between Housing Finance and Macroeconomics Variables in Malaysia

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Binti Mohd Shukor Nur Baizura

2016-01-01

Full Text Available Housing finance is one of the factors that contribute in the overall economy growth of the country. The purpose of this paper is to analyse the relationship of housing finance variable and the macroeconomic variables in Malaysia. By adopting time series technique of Vector Auto regression (VAR and Impulse Response to determine the dynamic relationship between the macroeconomic and housing finance variable. The cointegration result shows that there exists a long run relationship between the macroeconomic variable and housing finance variable. The finding from impulse response function indicates that Gross Domestic Product (GDP response positively to the Primary Mortgage Market (PMM, which shows that during the good economy there are more housing loan extends by the banking institution. Meanwhile, interest rate response negatively to Secondary Mortgage Market (SMM, which implies that during the financial crisis, more housing loan sold to the Secondary Mortgage Market as one of the measure by the government to increase liquidity in banking institutions. As a conclusion, there is presence of relationship between the variable which change in one variable will affect the other variable in the long run.

A Study of the Kepler K2 Variable EPIC 211957146 Exhibiting a Variable O’ Connell Effect

Energy Technology Data Exchange (ETDEWEB)

Sriram, K.; Malu, S.; Rao, P. Vivekananda [Department of Astronomy, Osmania University, Hyderabad 500007 (India); Choi, C. S., E-mail: astrosriram@yahoo.co.in [Korea Astronomy and Space Science Institute, Daejeon 34055 (Korea, Republic of)

2017-05-01

We present the multi-band photometric and spectroscopic study of an over-contact binary system, EPIC 211957146. The light curves exhibit a variable O’ Connell effect, confirmed from our observational data and the Kepler K2 data. The best photometric solution incorporating a dark spot over the primary component unveils that the system has a low-mass ratio ( q  ∼ 0.17) and a high inclination ( i  ∼ 85°). To confirm the solution and constrain the uncertainty, Monte-Carlo simulations are performed and the results are reported. Based on the O–C diagram analysis, we see that the variable shows a period increase at the rate of dP / dt  ∼ 1.06 × 10{sup −6} days yr{sup −1}, which is higher than the theoretically predicted value. Presence of a third body having a period of ∼16.23 years is evident from the O–C diagram. No filled-in effect is observed in the H α line, while the effect is vividly present in the Na line. From the Kepler K2 data, we found that the primary and secondary minima exhibit an anti-correlated O–C variation followed by an erratic behavior. This is possibly caused by the longitudinal motion of the spot, and hence, we set a lower limit of ∼40 days for the spot modulation. We also observe a possibly associated photometric difference in the primary depth by comparing our light curves with Kepler K2 normalized light curves. This system has a low-mass ratio and a high fill-out factor, and, theoretically, such a physical configuration would lead to a merger.

Light Curve Periodic Variability of Cyg X-1 using Jurkevich Method ...

Indian Academy of Sciences (India)

Abstract. The Jurkevich method is a useful method to explore periodic- ity in the unevenly sampled observational data. In this work, we adopted the method to the light curve of Cyg X-1 from 1996 to 2012, and found that there is an interesting period of 370 days, which appears in both low/hard and high/soft states.

Secondary Infections in Cancer Patients with Febrile Neutropenia

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Alpay Azap

2012-09-01

Full Text Available OBJECTIVE: Patients with neutropenia due to cancer chemotherapy are prone to severe infections. Cancer patients can experience >1 infectious episode during the same period of neutropenia. This study aimed to determine the etiological and clinical characteristics of secondary infectious episodes in cancer patients with febrile neutropenia and to identify the factors associated with the risk of secondary infectious episodes. METHODS: All cancer patients that received antineoplastic chemotherapy at Ankara University, School of Medicine, Department of Hematology between May 2004 and May 2005 and developed neutropenia were included in the study. Data were collected using survey forms that were completed during routine infectious diseases consultation visits. Categorical data were analyzed using the chi-square test, whereas Student’s t-test was used for continuous variables. Multivariate logistic regression analysis was performed to identify independent predictors of secondary infections (SIs. RESULTS: SIs were observed during 138 (53% of 259 febrile neutropenic episodes. Of the 138 episodes, 89 (64.5% occurred in male patients with a mean age of 40.9 years (range: 17-76 years. In total, 80% of the SIs were clinically or microbiologically documented. Factors on d 4 of the initial febrile episode were analyzed via a logistic regression model. The presence of a central intravenous catheter (OR: 3.01; P < 0.001, acute myeloid leukemia (AML as the underlying disease (OR: 2.12; P = 0.008, diarrhea (OR: 4.59; P = 0.005, and invasive aspergillosis (IA during the initial febrile episode (OR: 3.96; P = 0.009 were statistically significant risk factors for SIs. CONCLUSION: Among the cancer patients with neutropenia in the present study, AML as the underlying disease, the presence of a central venous catheter, diarrhea, and IA during the initial febrile episode were risk factors for the development of SIs.

Extended Delivery Time Analysis for Secondary Packet Transmission With Adaptive Modulation Under Interweave Cognitive Implementation

KAUST Repository

Wang, Wen-Jing

2017-05-02

Cognitive radio communication can opportunistically access underutilized spectrum for emerging wireless applications. With interweave cognitive implementation, a secondary user (SU) transmits only if primary user does not occupy the channel and waits for transmission otherwise. Therefore, secondary packet transmission involves both transmission periods and waiting periods. The resulting extended delivery time (EDT) is critical to the throughput analysis of secondary system. In this paper, we study the EDT of secondary packet transmission with adaptive modulation under interweave implementation to facilitate the delay analysis of such cognitive radio system. In particular, we propose an analytical framework to derive the probability density functions of EDT considering random-length SU transmission and waiting periods. We also present selected numerical results to illustrate the mathematical formulations and to verify our analytical approach.

A survey for southern delta Scuti variable stars

International Nuclear Information System (INIS)

McInally, C.J.; Austin, R.R.D.

1978-01-01

Twenty-nine field stars have been tested photoelectrically for short-period variability. Eighteen of these stars have spectral types between A2 and F5 and are not Am stars; of these, six have been discovered to be variable and one is a suspected variable. HD 185969, with a period of 0.361 day, has the longest known period for a star of the delta Scuti type. The predominance of discovered variables with amplitudes close to the detection limit is suggestive of most stars in the instability strip being pulsators. (author)

New O-C Observations for 150 Algols: Insight to the Origins of Period Shifts

Science.gov (United States)

Hoffman, D. I.; Harrison, T. E.; McNamara, B. J.; Vestrand, W. T.

2005-12-01

Many eclipsing binaries of type Algol, RS CVn, and W UMa have observed orbital period shifts. Of these, many show both increasing and decreasing period shifts. Two leading explanations for these shifts are third body effects and magnetic activity changing the oblateness of the secondary, though neither one can explain all of the observed period oscillations. The first-generation Robotic Optical Transient Search Experiment (ROTSE-I) based in Los Alamos, NM, was primarily designed to look for the optical counterparts to gamma-ray bursts as well as searching for other optical transients not detected in gamma-rays. The telescope, consisting of four 200mm camera lenses, can image the entire northern sky twice in a night, which is a very useful tool in monitoring relatively bright eclipsing binaries for period shifts. The public data release from ROTSE-I, the Northern Sky Variability Survey (NSVS), spans one year of data stating in April, 1999. O-C data for 150 eclipsing binaries are presented using the NSVS data. We revisit work by Borkovits and Hegedüs on some third body candidates in several eclipsing binary systems using recent AAVSO and NSVS data. Some unusual light curves of eclipsing binaries produced from NSVS data is presented and discussed.

ASASSN-16dt and ASASSN-16hg: Promising candidate period bouncers

Science.gov (United States)

Kimura, Mariko; Isogai, Keisuke; Kato, Taichi; Taguchi, Kenta; Wakamatsu, Yasuyuki; Hambsch, Franz-Josef; Monard, Berto; Myers, Gordon; Dvorak, Shawn; Starr, Peter; Brincat, Stephen M.; de Miguel, Enrique; Ulowetz, Joseph; Itoh, Hiroshi; Stone, Geoff; Nogami, Daisaku

2018-04-01

We present optical photometry of superoutbursts that occurred in 2016 of two WZ Sge-type dwarf novae (DNe), ASASSN-16dt and ASASSN-16hg. Their light curves showed a dip in brightness between the first plateau stage with no ordinary superhumps (or early superhumps) and the second plateau stage with ordinary superhumps. We find that the dip is produced by the slow evolution of the 3 : 1 resonance tidal instability and that it would likely be observed in low mass-ratio objects. An estimated mass ratio (q ≡ M2/M1) from the period of developing (stage A) superhumps [0.06420(3) d] was 0.036(2) in ASASSN-16dt. Additionally, its superoutburst has many properties similar to those in other low-q WZ Sge-type DNe: long-lasting stage-A superhumps, small superhump amplitudes, long delay of ordinary-superhump appearances, and a slow decline rate in the plateau stage with superhumps. Its very small mass ratio and observational characteristics suggest that this system is one of the best candidates for a period bouncer—a binary accounting for the missing population of post-period minimum cataclysmic variables. Although it is not clearly verified due to the lack of detection of stage-A superhumps, ASASSN-16hg might be a possible candidate for period bouncers on the basis of the morphology of its light curves and the small superhump amplitudes. Many outburst properties of period bouncer candidates would originate from the small tidal effects of their secondary stars.

Antigenic variation of TprK facilitates development of secondary syphilis.

Science.gov (United States)

Reid, Tara B; Molini, Barbara J; Fernandez, Mark C; Lukehart, Sheila A

2014-12-01

Although primary syphilis lesions heal spontaneously, the infection is chronic, with subsequent clinical stages. Healing of the primary chancre occurs as antibodies against outer membrane antigens facilitate opsonophagocytosis of the bacteria by activated macrophages. TprK is an outer membrane protein that undergoes antigenic variation at 7 variable regions, and variants are selected by immune pressure. We hypothesized that individual TprK variants escape immune clearance and seed new disseminated lesions to cause secondary syphilis. As in human syphilis, infected rabbits may develop disseminated secondary skin lesions. This study explores the nature of secondary syphilis, specifically, the contribution of antigenic variation to the development of secondary lesions. Our data from the rabbit model show that the odds of secondary lesions containing predominately TprK variant treponemes is 3.3 times higher than the odds of finding TprK variants in disseminated primary lesions (odds ratio [OR] = 3.3 [95% confidence interval {CI}, 0.98 to 11.0]; P = 0.055) and that 96% of TprK variant secondary lesions are likely seeded by single treponemes. Analysis of antibody responses demonstrates significantly higher antibody titers to tprK variable region sequences found in the inoculum compared to reactivity to tprK variant sequences found in newly arising secondary lesions. This suggests that tprK variants escape the initial immune response raised against the V regions expressed in the inoculum. These data further support a role for TprK in immune evasion and suggest that the ability of TprK variants to persist despite a robust immune response is instrumental in the development of later stages of syphilis. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Pattern of teen menstruation among secondary school girls in south east Nigeria.

Science.gov (United States)

Nwokocha, Ada R C; Chinawa, Josephat M; Ubesie, Agozie C; Onukwuli, Vivian I; Manyike, Pius C

2016-03-01

Menstruation in the teenage age has assumed variable trends which is been influenced by several variables. This study is aimed at determining the pattern and trend of menstruation among teens attending secondary school in south east Nigeria and associated factors. Menstruation patterns were investigated using a stratified random sampling method of teens from junior secondary schools in Enugu, south east Nigeria. A self-administered questionnaire was developed and data analyzed using SPSS version 19. A total of 897 female teenagers aged 9-18 years completed the questionnaire with a mean age of 13.9±1.9 years. The mean age (SD) at onset of menarche was 12.5±1.2 years. Teenage girls with higher BMI achieved menarche earlier at age 8 and 9 when compared with their counterparts with lower BMI and this is statistically significant. F=7.60, df=8, p<0.001. Teens with a 14-day cycle had a higher BMI when compared with teens with longer cycle but this is not statistically significant. F=1.05, df=4, p=0.381. There is a statistical significance difference between teens duration of menstrual flow and BMI. Those with higher BMI had longer duration(4-5 days) compared with those with lower BMI. F=3.329, df=4, p=0.01 CONCLUSIONS: This study revealed that the mean age at onset of menarche was 12.5±1.2 years showing a continuing decreasing trend. Teens with higher BMI attain menarche earlier and had longer days of periods when compared with their counterpart with lower BMI.

Variable stars in the Pegasus dwarf galaxy (DDO 216)

Energy Technology Data Exchange (ETDEWEB)

Hoessel, J.G.; Abbott, M.J.; Saha, A.; Mossman, A.E.; Danielson, G.E. (Washburn Observatory, Madison, WI (USA) Space Telescope Science Institute, Baltimore, MD (USA) Palomar Observatory, Pasadena, CA (USA))

1990-10-01

Observations obtained over a period of five years of the resolved stars in the Pegasus dwarf irregular galaxy (DDO 216) have been searched for variable stars. Thirty-one variables were found, and periods established for 12. Two of these variable stars are clearly eclipsing variables, seven are very likely Cepheid variables, and the remaining three are probable Cepheids. The period-luminosity relation for the Cepheids indicates a distance modulus for Pegasus of m - M = 26.22 + or - 0.20. This places Pegasus very near the zero-velocity surface of the Local Group. 25 refs.

Heart rate variability during sleep in healthy term newborns in the early postnatal period

International Nuclear Information System (INIS)

Doyle, O M; Korotchikova, I; Boylan, G B; Lightbody, G; Marnane, W; Kerins, D

2009-01-01

Normative time- and frequency-domain heart rate variability (HRV) measures were extracted during quiet sleep (QS) and active sleep (AS) periods in 30 healthy babies. All newborn infants studied were less than 12 h old and the sleep state was classified using multi-channel video EEG. Three bands were extracted from the heart rate (HR) spectrum: very low frequency (VLF), 0.01–0.04 Hz; low frequency (LF), 0.04–0.2 Hz, and high frequency (HF), >0.2 Hz. All metrics were averaged across all patients and per sleep state to produce a table of normative values. A noticeable peak corresponding to activity in the RSA band was found in 80% patients during QS and 0% of patients during AS, although some broadband activity was observed. The majority of HRV metrics showed a statistically significant separation between QS and AS. It can be concluded that (i) activity in the RSA band is present during QS in the healthy newborn, in the first 12 h of life, (ii) HRV measures are affected by sleep state and (iii) the averaged HRV metrics reported here could assist the interpretation of HRV data from newborns with neonatal illnesses

ANALISIS PENGARUH VARIABEL MAKROEKONOMI TERHADAP INFLASI DI INDONESIA SEBELUM DAN SESUDAH DITERAPKANNYA KEBIJAKAN INFLATION TARGETING FRAMEWORK PERIODE 2002:1 –2010:12

Directory of Open Access Journals (Sweden)

Murti Sari Dewi

2017-11-01

Full Text Available This thesis want to see effect of macroeconomics variables of inflation in Indonesia before and after Inflation Targeting Framework Policy period 2002:1 – 2010:12. The data used in this study is a secondary data obtained from Bank Indonesia. Variables are in use, among others: the level of inflation (CPI, the money supply, government expenditure, exchange rates against the U.S. dollar, and the dummy variable. Analysis tool used is a dynamic model. This model explains the influence of the relationship between the dependent variable with independent variables in the short and long term. The results of this study concluded that the variables in the money supply, government expenditure , and exchange rates have a significant effect on inflation in the long run, while in the short term had no significant effect on inflation, so that this study produces a long-term equation. Based on the results of previous studies both concluded that the variables in the money supply, government expenditure , and exchange rates have a significant effect on inflation in the long run, while in the short term had no significant effect on inflation.

Variability of Atmospheric Radon-222 and Secondary Aerosol Components in Accordance with Air Mass Transport Pathways at Jeju Island, Korea, during 2011-2014

Energy Technology Data Exchange (ETDEWEB)

Bu, Jun-Oh; Song, Jung-Min; Kim, Won-Hyung; Kang, Chang-Hee [Jeju National University, Jeju (Korea, Republic of); Chambers, Scott D.; Williams, Alastair G. [Australian Nuclear Science and Technology Organisation, Kirrawee DC (Australia); Lee, Chulkyu [Korea Meteorological Administration, Seoul (Korea, Republic of)

2016-06-15

Real-time monitoring of hourly atmospheric Radon-222 concentration and three daily monitoring of the secondary aerosol components of PM{sub 10} were performed throughout 2011-2014 at Gosan station, Jeju Island, in order to characterize their background levels and temporal variation. The annual mean radon and PM{sub 10} mass concentrations were 2326 ± 1198 mBq/m{sup 3} and 37.1 ± 19.5 μg/m{sup 3}, respectively. Based on cluster analyses of air mass back trajectories, the frequencies of air masses originating from continental China, the Korean Peninsula, and North Pacific Ocean routes were 53, 28, and 19%, respectively. When the air masses were transported to Jeju Island from continental China, the concentrations of radon and secondary aerosol components (nss-SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, NH{sub 4}{sup +}) were relatively high: 2577 mBq/m{sup 3} and 14.4 μg/m{sup 3}, respectively. In cases when the air masses have moved from the Korean Peninsula, the corresponding concentrations were 2247 mBq/m{sup 3} and 11.4 μg/m{sup 3}, respectively. On the other hand, when the air masses came from the North Pacific Ocean, their radon and secondary aerosol concentrations decreased much further, 1372 mBq/m{sup 3} and 10.5 μg/m{sup 3}, respectively. Consequently, the variability of atmospheric radon concentrations at Gosan station might be characterized by synoptic changes in air mass fetch as well as diurnal changes in atmospheric mixing depth.

Long-period variables in the Large Magellanic Cloud. II. Infrared photometry, spectral classification, AGB evolution, and spatial distribution

International Nuclear Information System (INIS)

Hughes, S.M.G.; Wood, P.R.

1990-01-01

Infrared JHK photometry and visual spectra have been obtained for a large sample of long-period variables (LPVs) in the Large Magellanic Cloud (LMC). Various aspects of the asymptotic giant branch (AGB) evolution of LPVs are discussed using these data. The birth/death rate of LPVs of different ages in the LMC is compared with the birth rates of appropriate samples of planetary nebulas, clump stars, Cepheids, and OH/IR stars. It appears that there are much fewer large-amplitude LPVs per unit galactic stellar mass in the LMC than in the Galaxy. It is suggested that this may be due to the fact that the evolved intermediate-age AGB stars in the LMC often turn into carbon stars, which tend to have smaller pulsation amplitudes than M stars. There is also a major discrepancy between the number of LPVs in the LMC (and in the Galaxy) and the number predicted by the theories of AGB evolution, pulsation, and mass loss. A distance modulus to the LMC of 18.66 + or - 0.05 is derived by comparing the LMC LPVs with P about 200 days with the 47 Tucanae Mira variables in the (K, log P) plane. 64 refs

Research of Precataclysmic Variables with Radius Excesses

Science.gov (United States)

Deminova, N. R.; Shimansky, V. V.; Borisov, N. V.; Gabdeev, M. M.; Shimanskaya, N. N.

2017-06-01

The results of spectroscopic observations of the pre-cataclysmic variable NSVS 14256825, which is a HW Vir binary system, were analyzed. The chemical composition is determined, the radial velocities and equivalent widths of a given star are measured. The fundamental parameters of the components were determined (R1 = 0.166 R⊙ , M2 = 0.100 M⊙ , R2 = 0.122 R⊙). It is shown that the secondary component has a mass close to the mass of brown dwarfs. A comparison of two close binary systems is made: HS 2333 + 3927 and NSVS 14256825. A radius-to-mass relationship for the secondary components of the studied pre-cataclysmic variables is constructed. It is concluded that an excess of radii relative to model predictions for MS stars is observed in virtually all systems.

Perspectives for short timescale variability studies with Gaia

Science.gov (United States)

Roelens, M.; Eyer, L.; Mowlavi, N.; Lecoeur-Taïbi, I.; Rimoldini, L.; Blanco-Cuaresma, S.; Palaversa, L.; Süveges, M.; Charnas, J.; Wevers, T.

2017-12-01

We assess the potential of Gaia for detecting and characterizing short timescale variables, i.e. at timescale from a few seconds to a dozen hours, through extensive light-curve simulations for various short timescale variable types, including both periodic and non-periodic variability. We evidence that the variogram analysis applied to Gaia photometry should enable to detect such fast variability phenomena, down to amplitudes of a few millimagnitudes, with limited contamination from longer timescale variables or constant sources. This approach also gives valuable information on the typical timescale(s) of the considered variation, which could complement results of classical period search methods, and help prepare ground-based follow-up of the Gaia short timescale candidates.

Sexual risk during pregnancy and postpartum periods among HIV-infected and -uninfected South African women: Implications for primary and secondary HIV prevention interventions.

Science.gov (United States)

Joseph Davey, Dvora; Farley, Elise; Gomba, Yolanda; Coates, Thomas; Myer, Landon

2018-01-01

HIV acquisition in pregnancy and breastfeeding contributes significantly toward pediatric HIV infection. However, little is known about how sexual behavior changes during pregnancy and postpartum periods which will help develop targeted HIV prevention and transmission interventions, including pre-exposure prophylaxis (PrEP). Cross-sectional study in HIV-infected and uninfected pregnant and postpartum women in Cape Town, South Africa. Interviewers collected survey data on demographic, sexual behaviors, and alcohol use among pregnant and post-partum women. We report descriptive results of sexual behavior by trimester and postpartum period, and results of multivariable logistic regression stratified by pregnancy status. We enrolled 377 pregnant and postpartum women (56% pregnant, 40% HIV-infected). During pregnancy, 98% of women reported vaginal sex (8% anal sex, 44% oral sex) vs. 35% and 88% during the periods 0-6 and 7-12 months postpartum, respectively (p1 partner in the past 12-months compared to postpartum women (18% vs. 13%, respectively, p6-months postpartum (13 mean sex acts in first trimester; 17 mean sex acts >6-months postpartum). Pregnant women had increased odds of reporting condomless sex at last sex (aOR = 2.96;95%CI = 1.84-4.78) and ever having condomless sex in past 3-months (aOR = 2.65;95%CI = 1.30-5.44) adjusting for age, HIV status, and sex frequency compared to postpartum women. We identified that sexual behaviors and risk behaviors were high and changing during pregnancy and postpartum periods, presenting challenges to primary and secondary HIV prevention efforts, including PrEP delivery to pregnant and breastfeeding women.

Interannual variability of Danube waters propagation in summer period of 1992-2015 and its influence on the Black Sea ecosystem

Science.gov (United States)

Kubryakov, A. A.; Stanichny, S. V.; Zatsepin, A. G.

2018-03-01

The propagation of the Danube River plume has strong interannual variability that impacts the local balance of nutrients and the thermohaline structure in the western Black Sea. In the present study, we use a particle-tracking model based on satellite altimetry measurements and wind reanalysis data, as well as satellite measurements (SeaWiFS, MODIS), to investigate the interannual variability in the Danube plume pathways during the summer from 1993 to 2015. The wind conditions largely define the variability in the Danube water propagation. Relatively low-frequency variability (on periods of a week to months) in the wind stress curl modulates the intensity of the geostrophic Rim Current and related mesoscale eddy dynamics. High-frequency offshore wind-drift currents transport the plume across isobaths and provide an important transport link between shelf and offshore circulation. Inherent plume dynamics play an additional role in the near-mouth transport of the plume and its connection with offshore circulation. During the years with prevailing northeast winds ( 30% of studied cases), which are usually accompanied by increased wind curl over the Black Sea and higher Danube discharge, an alongshore southward current at the NorthWestern Shelf (NWS) is formed near the western Black Sea coast. Advected southward, the Danube waters are entrained in the Rim Current jet, which transports them along the west coast of the basin. The strong Rim Current, fewer eddies and downwelling winds substantially decrease the cross-shelf exchange of nutrients. During the years with prevailing southeastern winds ( 40%), the Rim Current is less intense. Mesoscale eddies effectively trap the Danube waters, transporting them to the deep western part of the basin. The low- and high-frequency southeastern wind-drift currents contribute significantly to cross-isobath plume transport and its connection with offshore circulation. During several years ( 15%), the Danube waters moved eastward to

Implications of the Secondary Eclipse of Exoplanet HAT-P-11b

Science.gov (United States)

Barry, Richard K.; Deming, L. D.; Bakos, G.; Harrington, J.; Madhusudhan, N.; Noyes, R.; Seager, S.

2010-01-01

We observed exoplanet HAT-P-11b and have successfully detected its secondary eclipse. We conducted observations using the Spitzer Space Telescope in the post-cryo mission at 3.6 microns for a period of 22 hours centered on the anticipated secondary eclipse time, to detect the eclipse and determine its phase. Having detected the secondary eclipse, we are at present making a more focused series of observations in both the 3.6 and 4.5 micron bands to fully characterize it. HAT-P-11b is one of only two known exo-Neptunes and has a period of 4.8878 days, radius of 0.422 RJ, mass of 0.081 MJ and semi-major axis 0.053 AU. Measurements of the secondary eclipse will serve to clarify two key issues; 1) the planetary brightness temperature and the nature of its atmosphere, and 2) the eccentricity of its orbit, with implications for its dynamical evolution. We discuss implications of these observations.

Secondary precipitation in an Al-Mg-Si-Cu alloy

International Nuclear Information System (INIS)

Buha, J.; Lumley, R.N.; Crosky, A.G.; Hono, K.

2007-01-01

Interruption of a conventional T6 heat treatment at 177 deg. C for the Al-Mg-Si-Cu alloy 6061 after a short period of time (20 min), by inserting a dwell period at a lower temperature (e.g. 65 deg. C), promotes secondary precipitation of Guinier-Preston (GP) zones. As a consequence, a much greater number of precursors to the β'' precipitates are produced so that a finer and denser dispersion of this phase is formed when T6 ageing is resumed. This change in microstructure causes significant and simultaneous improvements in tensile properties and fracture toughness. Secondary precipitation of GP zones occurs through a gradual evolution of a large number of Mg-Si(-Cu)-vacancy co-clusters formed during the initial ageing at 177 deg. C. The precise mechanism of secondary precipitation has been revealed by three-dimensional atom probe microscopy supplemented by transmission electron microscopy and differential scanning calorimetry

Service time analysis of secondary packet transmission with opportunistic channel access

KAUST Repository

Usman, Muneer; Yang, Hongchuan; Alouini, Mohamed-Slim

2014-01-01

Cognitive radio transceiver can opportunistically access the underutilized channels of primary systems for new wireless services. The secondary transmission may be interrupted by the primary user's transmission. To facilitate the delay analysis of such secondary packet transmission, we study the resulting extended delivery time for a fixed-size secondary packet that includes both transmission time and waiting time. In particular we derive the exact distribution functions of extended delivery time of secondary transmission for both continuous sensing and periodic sensing cases. Selected numerical results are presented for illustrating the mathematical formulation.

Service time analysis of secondary packet transmission with opportunistic channel access

KAUST Repository

Usman, Muneer

2014-09-01

Cognitive radio transceiver can opportunistically access the underutilized channels of primary systems for new wireless services. The secondary transmission may be interrupted by the primary user\\'s transmission. To facilitate the delay analysis of such secondary packet transmission, we study the resulting extended delivery time for a fixed-size secondary packet that includes both transmission time and waiting time. In particular we derive the exact distribution functions of extended delivery time of secondary transmission for both continuous sensing and periodic sensing cases. Selected numerical results are presented for illustrating the mathematical formulation.

Smoking patterns, depression, and sociodemographic variables among Flemish women during pregnancy and the postpartum period.

Science.gov (United States)

De Wilde, Katrien S; Trommelmans, Leen C; Laevens, Hans H; Maes, Lea R; Temmerman, Marleen; Boudrez, Hedwig L

2013-01-01

Relationships among feelings of depression, smoking behavior, and educational level during pregnancy have been documented. Feelings of depression may contribute to persistent smoking during pregnancy. No longitudinal studies assessing feelings of depression in women with different antepartum and postpartum smoking patterns are available. The aim was to determine relationships between depressive symptoms, sociodemographic characteristics, and smoking pattern during and after pregnancy. An observational, prospective, noninterventional study was conducted. Data were collected during two stages of pregnancy (T0: postpartum (T2: >6 weeks) in 523 Flemish women. Feelings of depression (measured using the Beck Depression Inventory [BDI]), smoking behavior, and sociodemographic variables were analyzed using a general linear mixed model implemented in SAS Proc MIXED. Smokers and initial smokers reported significantly more depressive symptoms at all time points compared with recent ex-smokers, nonsmokers, and initial nonsmokers (p postpartum. Smoking patterns were associated with depression and showed complex interactions with educational level. Assessment and intervention for both smoking and depression are needed throughout the perinatal period to support the health of mothers, their infants, and families.

The textbook as classroom context variable

NARCIS (Netherlands)

Krammer, H.P.M.

1985-01-01

To explore the role of the textbook as a context variable in process—product relationships, data on teaching practices and learning outcomes from the IEA Classroom Environment Study in The Netherlands were used. The sample consisted of 50 secondary school mathematics classes and their teachers.

Zooplankton variability in the Zuari estuary, Goa

Digital Repository Service at National Institute of Oceanography (India)

Nair, V.R.; Achuthankutty, C.T.; Nair, S.R.S.

Short term variability in the secondary production and composition of zooplankton were studied during February to March 1979 by collecting zooplankton every alternate day from a station located near the mouth of Zuari. Irregularity in the production...

Patterns of examination anxiety among secondary school students ...

African Journals Online (AJOL)

Anxiety is a negative emotion which affects human beings irrespective of social status. However, individuals exhibit anxiety in different forms. This study therefore investigated the patterns of examination anxiety among secondary school students in Ilorin metropolis, Nigeria. The influence of variables of gender and school ...

Detection of the Secondary Eclipse of Exoplanet HAT P-11b

Science.gov (United States)

Barry, R. K.; Deming, L. D.; Bakos, G.; Harrington, J.; Madhusudhan, N.; Noyes, R.; Seager, S.

2010-01-01

We have successfully conducted secondary eclipse observations of exoplanet HAT-P-11b using the Spitzer Space Telescope. HAT-P-11b was, until very recently, the smallest transiting extrasolar planet yet found and one of only two known exo-Neptunes. We observed the system at 3.6 microns for a period of 22 hours centered on the anticipated secondary eclipse time, to detect the eclipse and determine its phase. Having detected the secondary eclipse, we are at present making a more focused series of observations in both the 3.6 and 4.5 micron bands to fully characterize it. HAT-P-11b has a period of 4.8878 days, radius of 0.422 RJ, mass of 0.081 MJ and semi-major axis 0.053 AU. Measurements of the secondary eclipse will serve to clarify two key issues; 1) the planetary brightness temperature and the nature of its atmosphere, and 2) the eccentricity of its orbit, with implications for its dynamical evolution. A precise determination of the orbit phase for the secondary eclipse will also be of great utility for Kepler observations of this system at visible wavelengths.

Long-Term Performance of Primary and Secondary Electroactive Biofilms Using Layered Corrugated Carbon Electrodes

International Nuclear Information System (INIS)

Baudler, André; Riedl, Sebastian; Schröder, Uwe

2014-01-01

The performance of primary and secondary electroactive biofilms grown on layered corrugated carbon (LCC) electrodes was studied over a period of several months. With an average projected current density of 6.7 mA cm −2 , the studied secondary electroactive biofilms outperformed the primary biofilms (3.0 mA cm −2 ) over the entire experimental period. At the same time, both, primary and secondary biofilms, exhibited a constant Coulomb efficiency of about 89%. The study further illustrates that three-dimensional electrodes such as LCC allow a sustained long-term performance without significant decrease in electrode performance.

Long-Term Performance of Primary and Secondary Electroactive Biofilms Using Layered Corrugated Carbon Electrodes

Energy Technology Data Exchange (ETDEWEB)

Baudler, André; Riedl, Sebastian; Schröder, Uwe, E-mail: uwe.schroeder@tu-bs.de [Institute of Environmental and Sustainable Chemistry, Technische Universität Braunschweig, Braunschweig (Germany)

2014-07-30

The performance of primary and secondary electroactive biofilms grown on layered corrugated carbon (LCC) electrodes was studied over a period of several months. With an average projected current density of 6.7 mA cm{sup −2}, the studied secondary electroactive biofilms outperformed the primary biofilms (3.0 mA cm{sup −2}) over the entire experimental period. At the same time, both, primary and secondary biofilms, exhibited a constant Coulomb efficiency of about 89%. The study further illustrates that three-dimensional electrodes such as LCC allow a sustained long-term performance without significant decrease in electrode performance.

Theoretical Perspectives on Critical Thinking Teaching: Reflections from Field Experiences from a Norwegian Lower Secondary School in Comparison to Tanzanian Secondary School Teaching Practices

Directory of Open Access Journals (Sweden)

Leatitia Gabriel Mashaza

2017-08-01

Full Text Available This paper presents the theoretical perspectives relevant to critical thinking as my topic of research during my teaching practice period which was conducted from 12th -28th October 2015 at Eidsvag secondary school in Bergen, Norway. As a requirement for Masters’ degree in social science education, all master students were required to engage in teaching practice in different Norwegian primary and secondary schools. Importantly, every student teacher was given a topic of concentration as a mini-research for the whole teaching practice period. My topic of research focused at exploring and gaining the theoretical and practical perspectives on critical thinking teaching by drawing some experiences from a Norwegian lower secondary school (Eidsvag skole in reflection to secondary school teaching practice experiences in Tanzania. Therefore, in this paper, my reflections with regard to the conditions favoring the possibility for critical thinking teaching and how it was enhanced by teachers at my practice school will be discussed. Further to that, I will also present the observed challenges of which, in my view, in way or another intervened the possibility for effective critical thinking teaching to take place.

Factors affecting Mathematics achievement of first-year secondary ...

African Journals Online (AJOL)

This study explores the sources of variability in Mathematics achievement of Ugandan students at the student, classroom and school level. The Mathematics score and questionnaire responses of 4,819 first-year secondary school students (Grade Seven, about 14-15 years old) from 78 classrooms of 49 schools were ...

A 60,000-year record of hydrologic variability in the Central Andes from the hydrogen isotopic composition of leaf waxes in Lake Titicaca sediments

Science.gov (United States)

Fornace, Kyrstin L.; Hughen, Konrad A.; Shanahan, Timothy M.; Fritz, Sherilyn C.; Baker, Paul A.; Sylva, Sean P.

2014-12-01

A record of the hydrogen isotopic composition of terrestrial leaf waxes (δDwax) in sediment cores from Lake Titicaca provides new insight into the precipitation history of the Central Andes and controls of South American Summer Monsoon (SASM) variability since the last glacial period. Comparison of the δDwax record with a 19-kyr δD record from the nearby Illimani ice core supports the interpretation that precipitation δD is the primary control on δDwax with a lesser but significant role for local evapotranspiration and other secondary influences on δDwax. The Titicaca δDwax record confirms overall wetter conditions in the Central Andes during the last glacial period relative to a drier Holocene. During the last deglaciation, abrupt δDwax shifts correspond to millennial-scale events observed in the high-latitude North Atlantic, with dry conditions corresponding to the Bølling-Allerød and early Holocene periods and wetter conditions during late glacial and Younger Dryas intervals. We observe a trend of increasing monsoonal precipitation from the early to the late Holocene, consistent with summer insolation forcing of the SASM, but similar hydrologic variability on precessional timescales is not apparent during the last glacial period. Overall, this study demonstrates the relative importance of high-latitude versus tropical forcing as a dominant control on glacial SASM precipitation variability.

Testing for entanglement with periodic coarse graining

Science.gov (United States)

Tasca, D. S.; Rudnicki, Łukasz; Aspden, R. S.; Padgett, M. J.; Souto Ribeiro, P. H.; Walborn, S. P.

2018-04-01

Continuous-variable systems find valuable applications in quantum information processing. To deal with an infinite-dimensional Hilbert space, one in general has to handle large numbers of discretized measurements in tasks such as entanglement detection. Here we employ the continuous transverse spatial variables of photon pairs to experimentally demonstrate entanglement criteria based on a periodic structure of coarse-grained measurements. The periodization of the measurements allows an efficient evaluation of entanglement using spatial masks acting as mode analyzers over the entire transverse field distribution of the photons and without the need to reconstruct the probability densities of the conjugate continuous variables. Our experimental results demonstrate the utility of the derived criteria with a success rate in entanglement detection of ˜60 % relative to 7344 studied cases.

Variability of Massive Young Stellar Objects in Cygnus-X

Science.gov (United States)

Thomas, Nancy H.; Hora, J. L.; Smith, H. A.

2013-01-01

Young stellar objects (YSOs) are stars in the process of formation. Several recent investigations have shown a high rate of photometric variability in YSOs at near- and mid-infrared wavelengths. Theoretical models for the formation of massive stars (1-10 solar masses) remain highly idealized, and little is known about the mechanisms that produce the variability. An ongoing Spitzer Space Telescope program is studying massive star formation in the Cygnus-X region. In conjunction with the Spitzer observations, we have conducted a ground-based near-infrared observing program of the Cygnus-X DR21 field using PAIRITEL, the automated infrared telescope at Whipple Observatory. Using the Stetson index for variability, we identified variable objects and a number of variable YSOs in our time-series PAIRITEL data of DR21. We have searched for periodicity among our variable objects using the Lomb-Scargle algorithm, and identified periodic variable objects with an average period of 8.07 days. Characterization of these variable and periodic objects will help constrain models of star formation present. This work is supported in part by the NSF REU and DOD ASSURE programs under NSF grant no. 0754568 and by the Smithsonian Institution.

Ecosystem, location, and climate effects on foliar secondary metabolites of lodgepole pine populations from central British Columbia.

Science.gov (United States)

Wallis, Christopher M; Huber, Dezene P W; Lewis, Kathy J

2011-06-01

Lodgepole pines, Pinus contorta Douglas ex Louden var. latifolia Engelm. ex S. Watson, are encountering increased abiotic stress and pest activity due to recent increases in temperature and changes in precipitation throughout their range. This tree species counters these threats by producing secondary metabolites, including phenolics and terpenoids. We examined foliar levels of lignin, soluble phenolics, monoterpenoids, sesquiterpenoids, and diterpenoids in 12 stands in British Columbia, Canada. We used these data to assess associations among foliar secondary metabolite levels and ecosystem, geographic, and climatic variables. Regressions were also performed to observe which combinations of variables best explained secondary metabolite variance. Stands of P. c. latifolia in the Coastal Western Hemlock and Interior Cedar/Hemlock biogeoclimatic zones had consistently greater foliar levels of almost all measured secondary metabolites than did other stands. Lignin was present in greater amounts in Boreal White/Black Spruce ecosystem (i.e., northern) stands than in southern stands, suggesting a role for this metabolite in pine survival in the boreal forest. Attempts to develop regression models with geographic and climatic variables to explain foliar secondary metabolite levels resulted in multiple models with similar predictive capability. Since foliar secondary metabolite levels appeared to vary most between stand ecosystem types and not as much due to geographic and climatic variables, metabolic profiles appeared best matched to the stress levels within local environments. It is unknown if differences in secondary metabolite levels are the result of genetic adaptation or phenotypic plasticity, but results from this and other studies suggest that both are important. These results are interpreted in light of ongoing efforts to assist in the migration of certain populations of P. c. latifolia northward in an effort to counter predicted effects of climate change.

QUASI-PERIODIC OSCILLATIONS AND BROADBAND VARIABILITY IN SHORT MAGNETAR BURSTS

Energy Technology Data Exchange (ETDEWEB)

Huppenkothen, Daniela; Watts, Anna L.; Uttley, Phil; Van der Horst, Alexander J.; Van der Klis, Michiel [Astronomical Institute ' ' Anton Pannekoek' ' , University of Amsterdam, Postbus 94249, 1090-GE Amsterdam (Netherlands); Kouveliotou, Chryssa [Office of Science and Technology, ZP12, NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States); Goegues, Ersin [Sabanc Latin-Small-Letter-Dotless-I University, Orhanl Latin-Small-Letter-Dotless-I -Tuzla, Istanbul 34956 (Turkey); Granot, Jonathan [The Open University of Israel, 1 University Road, P.O. Box 808, Ra' anana 43537 (Israel); Vaughan, Simon [X-Ray and Observational Astronomy Group, University of Leicester, Leicester LE1 7RH (United Kingdom); Finger, Mark H., E-mail: D.Huppenkothen@uva.nl [Universities Space Research Association, Huntsville, AL 35805 (United States)

2013-05-01

The discovery of quasi-periodic oscillations (QPOs) in magnetar giant flares has opened up prospects for neutron star asteroseismology. However, with only three giant flares ever recorded, and only two with data of sufficient quality to search for QPOs, such analysis is seriously data limited. We set out a procedure for doing QPO searches in the far more numerous, short, less energetic magnetar bursts. The short, transient nature of these bursts requires the implementation of sophisticated statistical techniques to make reliable inferences. Using Bayesian statistics, we model the periodogram as a combination of red noise at low frequencies and white noise at high frequencies, which we show is a conservative approach to the problem. We use empirical models to make inferences about the potential signature of periodic and QPOs at these frequencies. We compare our method with previously used techniques and find that although it is on the whole more conservative, it is also more reliable in ruling out false positives. We illustrate our Bayesian method by applying it to a sample of 27 bursts from the magnetar SGR J0501+4516 observed by the Fermi Gamma-ray Burst Monitor, and we find no evidence for the presence of QPOs in any of the bursts in the unbinned spectra, but do find a candidate detection in the binned spectra of one burst. However, whether this signal is due to a genuine quasi-periodic process, or can be attributed to unmodeled effects in the noise is at this point a matter of interpretation.

The misunderstood variable: Age effects as a function of type of instruction

Directory of Open Access Journals (Sweden)

Simone E. Pfenninger

2014-01-01

Full Text Available This study was designed to investigate the effects of age of onset and type of instruction on ultimate EFL attainment at the end of the period of normal schooling in Switzerland, measured in terms of written fluency, complexity, morphosyntactic accuracy, vocabulary size, and listening skills. Data were gathered from four groups of 18-year-old Swiss German learners of English: 50 were early starters who had attended an immersion (CLIL program in elementary school and who continued CLIL in secondary school (EARLY CLIL, 50 had followed the same elementary school program but then received traditional EFL instruction after elementary school (EARLY MIX, 50 were late starters who began learning English immersively in secondary school, (LATE CLIL, while the other 50 attended a traditional EFL program in secondary school (LATE NON-CLIL. Results show that age of onset alone does not seem to be the distinguishing variable since early introduction of English in elementary school did not result in a higher level of roficiency when exposure to the language was limited to a few hours of class per week. The performance of the EARLY MIX participants was equaled and in certain areas significantly surpassed by the other groups, despite the additional five years of English study they had had in elementary school. The best results were found when early CLIL instruction was followed up by the use of English as an additional language of instruction in secondary school (EARLY CLIL group, which confirms the link between young starting age, implicit learning and long and massive exposure.

Observations of long-period waves in the nearshore waters of central west coast of India during the fall inter-monsoon period

Digital Repository Service at National Institute of Oceanography (India)

Amrutha, M.M.; SanilKumar, V.; Jesbin, G.

variability in both long period waves and short period waves need more detailed study. Acknowledgments The authors acknowledge the Earth System Science Organization, Ministry of Earth Sciences, New Delhi for providing the financial support to conduct part... Geraldton. Proceedings of the 2009 Pacific Coasts and Ports Conference, Wellington, New Zealand. Mehta, A. V., & Krishnamurti, T. N., 1988. Interannual variability of the 30 to 50 day wave motions. Journal of the Meteorological Society of Japan, 66...

Photometric Analysis and Period Investigation of the EW Type ...

Indian Academy of Sciences (India)

Photometric Analysis and Period Investigation of the EW Type. Eclipsing ... binary with the less massive secondary component filling the inner Roche lobe. ..... Cox 2000) assuming that the primary component is a normal main sequence star.

Event-related potentials and secondary task performance during simulated driving.

Science.gov (United States)

Wester, A E; Böcker, K B E; Volkerts, E R; Verster, J C; Kenemans, J L

2008-01-01

Inattention and distraction account for a substantial number of traffic accidents. Therefore, we examined the impact of secondary task performance (an auditory oddball task) on a primary driving task (lane keeping). Twenty healthy participants performed two 20-min tests in the Divided Attention Steering Simulator (DASS). The visual secondary task of the DASS was replaced by an auditory oddball task to allow recording of brain activity. The driving task and the secondary (distracting) oddball task were presented in isolation and simultaneously, to assess their mutual interference. In addition to performance measures (lane keeping in the primary driving task and reaction speed in the secondary oddball task), brain activity, i.e. event-related potentials (ERPs), was recorded. Performance parameters on the driving test and the secondary oddball task did not differ between performance in isolation and simultaneous performance. However, when both tasks were performed simultaneously, reaction time variability increased in the secondary oddball task. Analysis of brain activity indicated that ERP amplitude (P3a amplitude) related to the secondary task, was significantly reduced when the task was performed simultaneously with the driving test. This study shows that when performing a simple secondary task during driving, performance of the driving task and this secondary task are both unaffected. However, analysis of brain activity shows reduced cortical processing of irrelevant, potentially distracting stimuli from the secondary task during driving.

Variable stars

International Nuclear Information System (INIS)

Feast, M.W.; Wenzel, W.; Fernie, J.D.; Percy, J.R.; Smak, J.; Gascoigne, S.C.B.; Grindley, J.E.; Lovell, B.; Sawyer Hogg, H.B.; Baker, N.; Fitch, W.S.; Rosino, L.; Gursky, H.

1976-01-01

A critical review of variable stars is presented. A fairly complete summary of major developments and discoveries during the period 1973-1975 is given. The broad developments and new trends are outlined. Essential problems for future research are identified. (B.R.H. )

SPECKLE INTERFEROMETRY OF SECONDARY COMPONENTS IN NEARBY VISUAL BINARIES

International Nuclear Information System (INIS)

Tokovinin, Andrei; Horch, Elliott P.

2016-01-01

Statistical characterization of secondary subsystems in binaries helps to distinguish between various scenarios of multiple-star formation. The Differential Speckle Survey Instrument was used at the Gemini-N telescope for several hours in 2015 July to probe the binarity of 25 secondary components in nearby solar-type binaries. Six new subsystems were resolved, with meaningful detection limits for the remaining targets. The large incidence of secondary subsystems agrees with other similar studies. The newly resolved subsystem HIP 115417 Ba,Bb causes deviations in the observed motion of the outer binary from which an astrometric orbit of Ba,Bb with a period of 117 years is deduced.

Heart rate variability biofeedback intervention for reduction of psychological stress during the early postpartum period.

Science.gov (United States)

Kudo, Naoko; Shinohara, Hitomi; Kodama, Hideya

2014-12-01

This study examined the effectiveness of heart rate variability (HRV) biofeedback intervention for reduction of psychological stress in women in the early postpartum period. On postpartum day 4, 55 healthy subjects received a brief explanation about HRV biofeedback using a portable device. Among them, 25 mothers who agreed to implement HRV biofeedback at home were grouped as the biofeedback group, and other 30 mothers were grouped as the control group. At 1 month postpartum, there was a significant decrease in total Edinburgh Postnatal Depression Scale score (P biofeedback group; this change was brought about mainly by decreases in items related to anxiety or difficulty sleeping. There was also a significant increase in standard deviation of the normal heartbeat interval (P biofeedback group after adjusting for potential covariates. In conclusion, postpartum women who implemented HRV biofeedback after delivery were relatively free from anxiety and complained less of difficulties sleeping at 1 month postpartum. Although the positive effects of HRV biofeedback may be partly attributable to intervention effects, due to its clinical outcome, HRV biofeedback appears to be recommendable for many postpartum women as a feasible health-promoting measure after childbirth.

Impact of the infectious period on epidemics

Science.gov (United States)

Wilkinson, Robert R.; Sharkey, Kieran J.

2018-05-01

The duration of the infectious period is a crucial determinant of the ability of an infectious disease to spread. We consider an epidemic model that is network based and non-Markovian, containing classic Kermack-McKendrick, pairwise, message passing, and spatial models as special cases. For this model, we prove a monotonic relationship between the variability of the infectious period (with fixed mean) and the probability that the infection will reach any given subset of the population by any given time. For certain families of distributions, this result implies that epidemic severity is decreasing with respect to the variance of the infectious period. The striking importance of this relationship is demonstrated numerically. We then prove, with a fixed basic reproductive ratio (R0), a monotonic relationship between the variability of the posterior transmission probability (which is a function of the infectious period) and the probability that the infection will reach any given subset of the population by any given time. Thus again, even when R0 is fixed, variability of the infectious period tends to dampen the epidemic. Numerical results illustrate this but indicate the relationship is weaker. We then show how our results apply to message passing, pairwise, and Kermack-McKendrick epidemic models, even when they are not exactly consistent with the stochastic dynamics. For Poissonian contact processes, and arbitrarily distributed infectious periods, we demonstrate how systems of delay differential equations and ordinary differential equations can provide upper and lower bounds, respectively, for the probability that any given individual has been infected by any given time.

V 1343 aquilae (SS 433) as a double-periodic star

International Nuclear Information System (INIS)

Goranskij, V.P.

1983-01-01

The new computer method of double periodicity search earlier tested on the Blazhko effect in RR Lyrae type variable stars is applied to define more precise periods of brightness variability of the binary V 1343 Aql (SS 433). Computer program was used in the two-parameter search regime. The obtained periods are P 1 = 13sup(d).074+-0sup(d).008 and P 2 = 163sup(d).8+-1sup(d).2. The periodically repeating brithness curve deeps treated as primary minima (the accretion disc eclipsed by the star) vary their shape with the phase of period P 2 . The expected eclipse at 1979 October 16 did nor occur

Economic literacy amongst the secondary school teachers in Perak Malaysia

Directory of Open Access Journals (Sweden)

Nek Kamal Yeop Yunus, Norasibah Abdul Jalil

2011-01-01

Full Text Available The aim of the study is to determine the relationship between economics education exposure, saving, expenditure, investment and economics literacy amongst teachers in secondary schools in Perak. The theoretical framework was designed based on the literature and hence five hypotheses for the study were formulated. The samples were selected by quota sampling methods. The data were collected by distributing structured 35 items questionnaires to 100 teachers in secondary schools in eight districts in Perak. The instrument was adapted form Leader Behaviour Description Questionnaires which were used to measure economic literacy. Only 60 questionnaires were returned and analysed which gave 60% respond rate. Data collected were sorted out and keyed in into SPSS version 17. The data were analysed using descriptive and inferential statistics to answer the research questions. The result of the analyses showed that there was significant relationship between economics education and its predictors. Together the independent variables explained 81.7% of the variance in the dependent variables. The remaining 18.3% was due to unidentified variables. In relation to that, the study had contributed some knowledge about the understanding of economic of literacy. For future research, it is recommended that other than the above variables might influence economic literacy perhaps with a bigger samples and wider scope.

Closed Loop Sawtooth Period Control Using Variable Eccd Injection Angles on Tore Supra

International Nuclear Information System (INIS)

Lennholm, M.; Eriksson, L.G.; Turco, F.; Bouquey, F.; Darbos, C.; Dumont, R.; Giruzzi, G.; Jung, M.; Lambert, R.; Magne, R.; Molina, D.; Moreau, P.; Rimini, F.; Segui, J.L.; Song, S.; Traisnel, E.

2009-01-01

Closed loop control of the period of fast ion stabilized sawtooth has been demonstrated for the first time on Tore Supra by varying the electron cyclotron current drive (ECCD) injection angles in real time. Fast ions generated by up to 4 MW of central ion cyclotron resonance heating (ICRH) increased the sawtooth period from the ohmic value of 25 ms to 60 to 100 ms. This sawtooth period was reduced to 30 ms by the addition of only 300 kW of ECCD. In ICRH heated shots where the normalized minor radius of the ECCD absorption location was swept from 0.4 to 0.05 in 4 s, the sawtooth period showed an abrupt change from 70 to 30 ms when the ECCD deposition normalized minor radius reached ∼ 0.2. This short period was then maintained until the absorption location moved well inside the sawtooth inversion radius at which point it abruptly returned to 70 ins. A closed loop controller was implemented that allowed the sawtooth period to be switched in real time between short and long sawteeth with a response time of the order of 1 s. (authors)

LAMURU CORN SEED QUALITY IN DIFFERENT STORE PERIOD WITH SOME STUDIES METHOD

Directory of Open Access Journals (Sweden)

Rahmawati

2014-01-01

Full Text Available Research quality of seed executed at green house and laboratory of seed, Hall of Research of Crop of Serealia Maros in May 2013. Maize used is Lamuru coming from warehouse of UPBS Balitsereal with period keep 12 and 23 month. Research conducted by using RCD four replicated. Result: test by using sand media show percentage germinate, speed growth, length root, amount root of secondary, long of shoot and seed of sprout do not differ significant. Examinatied by piercing paper test to show percentage germinated, speed growth and dry wight of sprout differ significant, while length root, amount secondary root and seed shoot not significant. Use of Brick gravel test to show same result by is piercing paper test except dry weight of sprout at brick gravel test to show result which do not significant. Seed with period keep 12 month have percentage germinate, dry weight sprout, long root primary, sum up root secondary and same seed length at all method test, while speed growth to differ significant at piercing paper test. Seed with period keep 23 month show different result by 12 month. Dry weight sprout, long root primary, sum up root secondary and seed length shoot show same result, while speed growth show different result at third test method. Percentage germinate obtained by piercing paper test to differ significant by brick is gravel test and sand media.

Dampak Modal Intelektual Terhadap Kinerja Bank Umum Nasional Periode 2010-2015

Directory of Open Access Journals (Sweden)

Endang Pitaloka

2017-12-01

Full Text Available Abstract. The purpose of this study is to find out the influence of intellectual capital on Return on Asset of the National Commercial Bank 2010-2015 period. The intellectual capital variable as independent variable consists of Human Capital / Human Capital (HCE, Structured Capital (SCE, Capital Employed Capital (CEE.,and the dependent variable is Return on Assets (ROA. This study used secondary data sourced from the financial statements. The samples of this study are banks with assets of more than Rp. 50 trillion, include state-owned enterprise bank and private bank. Data analysis technique used in this research is pooled regression analysis. The results showed that both Human Capital (HCE and Capital Employed (CEE have significant influence and positive impact on Return on Asset (ROA at α = 5%. Although Structured Capital (SCE has no significant influence on Return on Asset (ROA, but SCE has positive impact on Return on Assets (ROA.   Keywords: Intellectual Capital; HCE; SCE; CEE; ROA.   Abstrak. Penelitian ini bertujuan untuk mengetahui pengaruh modal intelektual terhadap kinerja Bank Umum Nasional periode 2010-2015. Variabel modal intelektual sebagai variabel bebas terdiri dari: Modal Manusia / Human Capital (HCE, Modal Struktural / Structured Capital (SCE, Modal Kerja Capital Employed (CEE. Sedangkan variabel kinerja perusahaan sebagai variabel terikat adalah Return on Asset (ROA. Jenis data yang digunakan dalam penelitian ini adalah data sekunder yang bersumber dari laporan keuangan bank-bank yang diteliti. Adapun bank yang diteliti adalah bank umum milik pemerintah dan bank devisa swasta dengan aset lebih dari Rp. 50 triliun. Teknik analisis data yang digunakan dalam penelitian ini adalah analisis pooled regression analysis. Hasil penelitian menunjukkan bahwa Human Capital (HCE dan Capital Employed (CEE berdampak positif dan berpengaruh terhadap Return on Asset secara signifikan pada α = 5%. Variabel Structured Capital (SCE berdampak

Variable mechanical ventilation.

Science.gov (United States)

Fontela, Paula Caitano; Prestes, Renata Bernardy; Forgiarini, Luiz Alberto; Friedman, Gilberto

2017-01-01

To review the literature on the use of variable mechanical ventilation and the main outcomes of this technique. Search, selection, and analysis of all original articles on variable ventilation, without restriction on the period of publication and language, available in the electronic databases LILACS, MEDLINE®, and PubMed, by searching the terms "variable ventilation" OR "noisy ventilation" OR "biologically variable ventilation". A total of 36 studies were selected. Of these, 24 were original studies, including 21 experimental studies and three clinical studies. Several experimental studies reported the beneficial effects of distinct variable ventilation strategies on lung function using different models of lung injury and healthy lungs. Variable ventilation seems to be a viable strategy for improving gas exchange and respiratory mechanics and preventing lung injury associated with mechanical ventilation. However, further clinical studies are necessary to assess the potential of variable ventilation strategies for the clinical improvement of patients undergoing mechanical ventilation.

Secondary Analysis under Cohort Sampling Designs Using Conditional Likelihood

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Olli Saarela

2012-01-01

Full Text Available Under cohort sampling designs, additional covariate data are collected on cases of a specific type and a randomly selected subset of noncases, primarily for the purpose of studying associations with a time-to-event response of interest. With such data available, an interest may arise to reuse them for studying associations between the additional covariate data and a secondary non-time-to-event response variable, usually collected for the whole study cohort at the outset of the study. Following earlier literature, we refer to such a situation as secondary analysis. We outline a general conditional likelihood approach for secondary analysis under cohort sampling designs and discuss the specific situations of case-cohort and nested case-control designs. We also review alternative methods based on full likelihood and inverse probability weighting. We compare the alternative methods for secondary analysis in two simulated settings and apply them in a real-data example.

Maladaptive social behaviour of students in secondary vocational education

NARCIS (Netherlands)

Koerhuis, Marie-José

2007-01-01

The aim of this thesis was twofold: Firstly to create a reliable and valid new instrument to measure maladaptive social behaviour (MSB) of students in secondary vocational education, and secondly to assess which school context variables could predict MSB at school. Three data-waves were conducted

Factors Influencing Stress, Burnout, and Retention of Secondary Teachers

Science.gov (United States)

Fisher, Molly H.

2011-01-01

This study examines the stress, burnout, satisfaction, and preventive coping skills of nearly 400 secondary teachers to determine variables contributing to these major factors influencing teachers. Analysis of Variance (ANOVA) statistics were conducted that found the burnout levels between new and experienced teachers are significantly different,…

Elastic Bands as a Component of Periodized Resistance Training.

Science.gov (United States)

Joy, Jordan M; Lowery, Ryan P; Oliveira de Souza, Eduardo; Wilson, Jacob M

2016-08-01

Joy, JM, Lowery, RP, Oliveira de Souza, E, and Wilson, JM. Elastic bands as a component of periodized resistance training. J Strength Cond Res 30(8): 2100-2106, 2016-Variable resistance training (VRT) has recently become a component of strength and conditioning programs. Prior research has demonstrated increases in power and/or strength using low loads of variable resistance. However, no study has examined using high loads of variable resistance as a part of a periodized training protocol to examine VRT within the context of a periodized training program and to examine a greater load of variable resistance than has been examined in prior research. Fourteen National Collegiate Athletic Association division II male basketball players were recruited for this study. Athletes were divided equally into either a variable resistance or control group. The variable resistance group added 30% of their 1 repetition maximum (1RM) as band tension to their prescribed weight 1 session per week. Rate of power development (RPD), peak power, strength, body composition, and vertical jump height were measured pretreatment and posttreatment. No baseline differences were observed between groups for any measurement of strength, power, or body composition. A significant group by time interaction was observed for RPD, in which RPD was greater in VRT posttraining than in the control group. Significant time effects were observed for all other variables including squat 1RM, bench press 1RM, deadlift 1RM, clean 3RM, vertical jump, and lean mass. Although there were no significant group ×-time interactions, the VRT group's percent changes and effect sizes indicate a larger treatment effect in the squat and bench press 1RM values and the vertical jump performed on the force plate and vertec. These results suggest that when using variable resistance as a component of a periodized training program, power and strength can be enhanced. Therefore, athletes who add variable resistance to 1 training

On the K-term and dispersion ratios of semi-regular variables

International Nuclear Information System (INIS)

Aslan, Z.

1981-01-01

Optical velocities of semi-regular (SR) and irregular (Lb) variables are analysed for a K-term. There is evidence for a dependence upon stellar period. Absorption lines in shorter period non-emission SR variables are blue-shifted relative to the centre-of-mass velocity by about 6 +- 3 km s -1 . Emission-line SR variables give a non-negative absorption K-term and Lb variables give no K-terms other than zero. Comparison is made with the K-terms implied by the OH velocity pattern in long-period variables. Dispersion ratios are also calculated. (author)

Possible impact of fixed point sources of SO2 in NSW to the secondary sulphate measurements at Richmond and the dependence of the background secondary sulphate on meteorological variables

International Nuclear Information System (INIS)

Crawford, C.; Cohen, D.D.; Stelcer, E.

2010-01-01

The contribution to secondary sulfate measurements at Richmond, Australia, from known point sources of SOz is investigated using air mass back trajectories. The conditional probability function (CPF) shows that contribution for days of high sulfur is from areas north east of the site. This is an area where known point sources of SOz, such as coal fired power stations, are located. The meteorological conditions associated with high sulfur days are examined and an artificial neural network is employed to determine the relationship between meteorological variables and sulfur measurements after the influence of known point sources was removed. It is shown that temperature and humidity have a nonlinear positive correlation with sulphate measurements, while wind speed, mixing layer depth and rainfall have a negative nonlinear correlation. In addition, the time of day at which air masses reach Richmond from the eastern and western power stations varies, and so thus the altitude at which the power stations are crossed. The time of day, as well as the altitude at which an SOz point source was passed, show an impact to the measured sulfate at Richmond, although the extent of this remains to be fully investigated

Mesohabitat mosaic in lowland braided rivers: Short-term variability of macroinvertebrate metacommunities

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Gemma Burgazzi

2017-04-01

Full Text Available Braided rivers are among the most variable and dynamic riverine systems. Changes in these environments are sudden and frequent, driven by the high hydrological variability. They host high levels of local heterogeneity, with many different habitats in close proximity establishing a mosaic of patches. This provides the conditions for high levels of biodiversity, with strong community variability in particular among the different habitats at the stream-reach level. Nevertheless, these systems are still poorly studied and their complexity is often not taken into account in biomonitoring protocols. We applied mixed effects modelling, spatial ordination techniques and beta-diversity partitioning (into nestedness and turnover components with the aim of improving the knowledge of braided rivers, investigating: i the organization of macroinvertebrate communities among the different habitats of a river reach, and ii the temporal variability of this organization (both among seasons and during summer. We predicted a differentiation of macroinvertebrate communities between distinct habitats within rivers, with this differentiation increasing during the low-flow period. We carried out our study in four braided rivers and streams of the Po River basin (Northern Italy sampling three different kinds of mesohabitats (main channel, secondary channel and pool in eight stations during seven campaigns from June 2015 to April 2016. We found a high variability of taxa richness, abundance and community structure among mesohabitats, with marginal ones accounting for the greater part of macroinvertebrate diversity. Secondary channels resulted as being the habitat hosting greater taxa diversity, with 10 exclusive taxa. Surprisingly the mesohabitat communities differed greatly during the seasonal phase, whereas their dissimilarity decreased during summer. This could be explained considering the summer flow reduction as a homogenizing force, leading to a general loss of the

Summer weather characteristics and periodicity observed over the period 1888-2013 in the region of Belgrade, Serbia

Science.gov (United States)

Vujović, Dragana; Todorović, Nedeljko; Paskota, Mira

2018-04-01

With the goal of finding summer climate patterns in the region of Belgrade (Serbia) over the period 1888-2013, different techniques of multivariate statistical analysis were used in order to analyze the simultaneous changes of a number of climatologic parameters. An increasing trend of the mean daily minimum temperature was detected. In the recent decades (1960-2013), this increase was much more pronounced. The number of days with the daily minimum temperature greater or equal to 20 °C also increased significantly. Precipitation had no statistically significant trend. Spectral analysis showed a repetitive nature of the climatologic parameters which had periods that roughly can be classified into three groups, with the durations of the following: (1) 6 to 7 years, (2) 10 to 18 years, and (3) 21, 31, and 41 years. The temperature variables mainly had one period of repetitiveness of 5 to 7 years. Among other variables, the correlations of regional fluctuations of the temperature and precipitation and atmospheric circulation indices were analyzed. The North Atlantic oscillation index had the same periodicity as that of the precipitation, and it was not correlated to the temperature variables. Atlantic multidecadal oscillation index correlated well to the summer mean daily minimum and summer mean temperatures. The underlying structure of the data was analyzed by principal component analysis, which detected the following four easily interpreted dimensions: More sunshine-Higher temperature, Precipitation, Extreme heats, and Changeable summer.

Biochemical trade-offs: evidence for ecologically linked secondary metabolism of the sponge Oscarella balibaloi.

Science.gov (United States)

Ivanisevic, Julijana; Thomas, Olivier P; Pedel, Laura; Pénez, Nicolas; Ereskovsky, Alexander V; Culioli, Gérald; Pérez, Thierry

2011-01-01

Secondary metabolite production is assumed to be costly and therefore the resource allocation to their production should be optimized with respect to primary biological functions such as growth or reproduction. Sponges are known to produce a great diversity of secondary metabolites with powerful biological activities that may explain their domination in some hard substrate communities both in terms of diversity and biomass. Oscarella balibaloi (Homoscleromorpha) is a recently described, highly dynamic species, which often overgrows other sessile marine invertebrates. Bioactivity measurements (standardized Microtox assay) and metabolic fingerprints were used as indicators of the baseline variations of the O. balibaloi secondary metabolism, and related to the sponge reproductive effort over two years. The bioactivity showed a significant seasonal variation with the lowest values at the end of spring and in early summer followed by the highest bioactivity in the late summer and autumn. An effect of the seawater temperature was detected, with a significantly higher bioactivity in warm conditions. There was also a tendency of a higher bioactivity when O. balibaloi was found overgrowing other sponge species. Metabolic fingerprints revealed the existence of three principal metabolic phenotypes: phenotype 1 exhibited by a majority of low bioactive, female individuals, whereas phenotypes 2 and 3 correspond to a majority of highly bioactive, non-reproductive individuals. The bioactivity was negatively correlated to the reproductive effort, minimal bioactivities coinciding with the period of embryogenesis and larval development. Our results fit the Optimal Defense Theory with an investment in the reproduction mainly shaping the secondary metabolism variability, and a less pronounced influence of other biotic (species interaction) and abiotic (temperature) factors.

Biochemical trade-offs: evidence for ecologically linked secondary metabolism of the sponge Oscarella balibaloi.

Directory of Open Access Journals (Sweden)

Julijana Ivanisevic

Full Text Available Secondary metabolite production is assumed to be costly and therefore the resource allocation to their production should be optimized with respect to primary biological functions such as growth or reproduction. Sponges are known to produce a great diversity of secondary metabolites with powerful biological activities that may explain their domination in some hard substrate communities both in terms of diversity and biomass. Oscarella balibaloi (Homoscleromorpha is a recently described, highly dynamic species, which often overgrows other sessile marine invertebrates. Bioactivity measurements (standardized Microtox assay and metabolic fingerprints were used as indicators of the baseline variations of the O. balibaloi secondary metabolism, and related to the sponge reproductive effort over two years. The bioactivity showed a significant seasonal variation with the lowest values at the end of spring and in early summer followed by the highest bioactivity in the late summer and autumn. An effect of the seawater temperature was detected, with a significantly higher bioactivity in warm conditions. There was also a tendency of a higher bioactivity when O. balibaloi was found overgrowing other sponge species. Metabolic fingerprints revealed the existence of three principal metabolic phenotypes: phenotype 1 exhibited by a majority of low bioactive, female individuals, whereas phenotypes 2 and 3 correspond to a majority of highly bioactive, non-reproductive individuals. The bioactivity was negatively correlated to the reproductive effort, minimal bioactivities coinciding with the period of embryogenesis and larval development. Our results fit the Optimal Defense Theory with an investment in the reproduction mainly shaping the secondary metabolism variability, and a less pronounced influence of other biotic (species interaction and abiotic (temperature factors.

The variable stars of NGC 1866

International Nuclear Information System (INIS)

Welch, D.L.; Cote, P.; Fischer, P.; Mateo, M.; Madore, B.F.

1991-01-01

A search has been conducted for new variables in the LMC cluster NGC 1866 using new multiepoch CCD photometry. Eight previously unknown Cepheid variables, most near the cluster core, are found. Of the new variables reported by Storm et al. (188), only six of 10 appear to be Cepheids and one of these is not a member. Periods and mean magnitudes and colors for sufficiently uncrowded variables are reported, as is one red giant variable of long period and one Cepheid which is a single-lined spectroscopic binary with a velocity semiamplitude greater than or equal to 10.5 km/s. The variation of light-curve amplitude with position in the instability strip is reported along with an apparently nonvariable star, which is a radial velocity member, in the strip. A true distance modulus of 18.57 + or - 0.01 mag is obtained for the cluster. 36 refs

[Final clinical indications and etiology in 1,023 enucleations. Descriptive databank evaluation with SPSS software in variable response mode with dummy variables].

Science.gov (United States)

Becker, H; Bialasiewicz, A A; Schaudig, U; Schäfer, H; von Domarus, D

2002-05-01

A new data bank developed for ophthalmopathology using a computer-generated, multidigital data code is expected to be able to accomplish complex clinicopathologic correlations of diagnoses and signs, as provided by (multiple) clinical events and histopathologically proven etiologies, and to facilitate the documentation of new data. In the ophthalmopathology laboratory 2890 eyes were examined between January 20, 1975 and December 12, 1996. The main diagnoses and patient data from this 22-year period were recorded. To facilitate the presentation of data, a 10-year period with eyes of 976 patients enucleated from December, 1986 to December, 1996 was chosen. Principal and secondary diagnoses served for establishing the data bank. The frequencies of successive histologic and clinical diagnoses were evaluated by a descriptive computing program using an SPSS-multi-response mode with dummy variables and a categorical variable listing of the software (SPSS version 10.0) classified as (a) non-filtered random, (b) filtered by multiple etiologies, and (c) filtered by multiple events. The principal groups (e.g., histologic diagnoses concerning etiology) and subgroups (e.g., trauma, neoplasia, surgery, systemic diseases, and inflammations) were defined and correlated with 798 separate diagnoses. From 11 diagnoses/events ascribed to the clinical cases, 11,198 namings resulted. Thus, a comparative study of complex etiologies and events leading to enucleation in different hospitals of a specific area may be performed using this electronic ophthalmopathologic data bank system. The complexity of rare disease and integration into a superimposed structure can be managed with this custom-made data bank. A chronologically and demographically oriented consideration of reasons for enucleation is thus feasible.

Needful Implements in Improving the Study and Scholastic Skills of Nigerian Secondary School Students

Science.gov (United States)

Adegoroye, Biodun-Smith; Ajagbe, Adesina Adunfe

2015-01-01

Showing concern about the consistent depreciation in expected study and scholastic behaviours among Secondary School students and the trailing failure in school test and exams and public exams, the authors gathered empirical report on the chosen variables among a randomly selected 1,200 secondary school students in JSS I, II, III, SSS I, II, III…

A Multifactor Pricing Model For Cat Bonds In The Secondary Market

OpenAIRE

Gomez, Laura; Carcamo, Ulises

2014-01-01

Given the relevance that Cat Bonds are taking in the financial markets, as well as their appeal for different types of investors, it becomes pertinent to understand the price dynamics of these securities in the secondary market. Several authors have developed and proposed different valuation approaches, focusing on the probability of occurrence of catastrophic events, as the main variable impacting the pricing of Cat bonds in the secondary market. However, the lack of inclusion of other facto...

Benthic macrofaunal structure and secondary production in tropical estuaries on the Eastern Marine Ecoregion of Brazil.

Science.gov (United States)

Bissoli, Lorena B; Bernardino, Angelo F

2018-01-01

Tropical estuaries are highly productive and support diverse benthic assemblages within mangroves and tidal flats habitats. Determining differences and similarities of benthic assemblages within estuarine habitats and between regional ecosystems may provide scientific support for management of those ecosystems. Here we studied three tropical estuaries in the Eastern Marine Ecoregion of Brazil to assess the spatial variability of benthic assemblages from vegetated (mangroves) and unvegetated (tidal flats) habitats. A nested sampling design was used to determine spatial scales of variability in benthic macrofaunal density, biomass and secondary production. Habitat differences in benthic assemblage composition were evident, with mangrove forests being dominated by annelids (Oligochaeta and Capitellidae) whereas peracarid crustaceans were also abundant on tidal flats. Macrofaunal biomass, density and secondary production also differed between habitats and among estuaries. Those differences were related both to the composition of benthic assemblages and to random spatial variability, underscoring the importance of hierarchical sampling in estuarine ecological studies. Given variable levels of human impacts and predicted climate change effects on tropical estuarine assemblages in Eastern Brazil, our data support the use of benthic secondary production to address long-term changes and improved management of estuaries in Eastern Brazil.

The Determinants of Hemoglobin Variability in Hemodialysis Patients

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Tomanoski Vasilije

2016-12-01

Full Text Available Introduction. Factors that have been reported to affect erythropoietin (EPO responsiveness in hemodialysis (HD patients include iron deficiency, chronic inflammation, secondary hyperparathyroidism, malnutrition and inadequate HD dose. The aim of the study was to analyze the deteminants of hemoglobin variability in HD patients. Methods. The study encompassed 526 patients (197 F and 329 M. According to HD vintage at the beginning of the study the patients were divided into two groups: group-1 encompassed 153 patients with HD vintage bellow 24 months, and group-2 encompassed 329 patients with HD vintage over 24 months. Over a period of 21 months after admission the following parameters were analyzed: hemoglobin (Hb, EPO dose, iron dose, HD dose (eKT/V, transferrin saturation (TSAT, C-reactive protein (CRP, ferritin and serum albumin at 3 months and parathyroid hormone (PTH at 6 months. Results. The percentage of patients with Hb>=105g/L significantly improved, and the average Hb level significantly increased in both groups over a period of 21 months. The average EPO and iron dose significantly decreased, but TSAT and ferritin levels significantly increased over a period of 21 months. The average eKT/V and s-albumin values significantly increased, but the average CRP and PTH levels significantly decresead over a period of 21 months. In group-1 EPO dose and CRP, but in group-2 EPO dose, ferritin, HD vintage, and iron dose were statistically significant predictors of the Hb level 9 months after admission. Conclusions. Insufficient EPO therapy, iron deficiency and chronic inflammation were the main factors of inadequate correction of anemia in HD patients before admission.

Nonlinear Development and Secondary Instability of Traveling Crossflow Vortices

Science.gov (United States)

Li, Fei; Choudhari, Meelan M.; Duan, Lian; Chang, Chau-Lyan

2014-01-01

Transition research under NASA's Aeronautical Sciences Project seeks to develop a validated set of variable fidelity prediction tools with known strengths and limitations, so as to enable "sufficiently" accurate transition prediction and practical transition control for future vehicle concepts. This paper builds upon prior effort targeting the laminar breakdown mechanisms associated with stationary crossflow instability over a swept-wing configuration relevant to subsonic aircraft with laminar flow technology. Specifically, transition via secondary instability of traveling crossflow modes is investigated as an alternate scenario for transition. Results show that, for the parameter range investigated herein, secondary instability of traveling crossflow modes becomes insignificant in relation to the secondary instability of the stationary modes when the relative initial amplitudes of the traveling crossflow instability are lower than those of the stationary modes by approximately two orders of magnitudes or more. Linear growth predictions based on the secondary instability theory are found to agree well with those based on PSE and DNS, with the most significant discrepancies being limited to spatial regions of relatively weak secondary growth, i.e., regions where the primary disturbance amplitudes are smaller in comparison to its peak amplitude. Nonlinear effects on secondary instability evolution is also investigated and found to be initially stabilizing, prior to breakdown.

[Secondary glaucoma in Paraguay. Etiology and incidence].

Science.gov (United States)

Strohl, A; Pozzi, S; Wattiez, R; Roesen, B; Miño de Kaspar, H; Klauss, V

1999-06-01

Glaucoma is the third-most-frequent cause of blindness in the world, with a total of 5.2 million blind people as a result of this disease; 80% live in developing countries. In Paraguay, after cataract it is the second-most-frequent-cause. Early detection of the risk factors and groups can help to avoid progress of this disease. Trauma, cataract and infectious uveitis represent special risks for developing secondary glaucoma, which is a more frequent cause of blindness in third-world countries than in industrialized nations. Until now there has been little data regarding the causes, disease course, and options for therapy. Therefore, secondary glaucoma was examined in Paraguay to obtain information on the situation in Latin America. The aim of the study was to explore the causes of secondary glaucoma for programs concerning prevention and therapy. From November 1996 to February 1997 patients with secondary glaucoma were examined at the University Hospital of Asunción, Paraguay. After the clinical examination the secondary glaucomas were classified. Patients with primary glaucoma were included in the same period of time as well in order to get the rate of secondary glaucoma. Altogether 293 patients were examined: 61 with secondary and 232 with primary glaucoma. The causes of secondary glaucoma in 73 eyes were: 20 (27%) with pseudoexfoliation glaucoma, 19 (26%) with post-traumatic glaucoma, 16 (22%) with neovascular glaucoma, 4 (5%) with lens-related glaucoma, 3 (4%) with glaucoma associated with ocular surgery, 2 (3%) with pigmentary and 2 (3%) with corticoid-induced glaucoma. A ratio of 4:1 primary glaucomas to secondary glaucomas was found. The development of special measures for prevention and early therapy is only possible if the causes of this severe disease are explored. The results of this study represent basic information and could help to introduce of prevention programs.

[Iatrogenic hyperthyroidism secondary to weight loss medication. Predictive factors for their precocious detention].

Science.gov (United States)

Goday, A; Recasens, A; Manresa, J M; Vila, J; Moix, S

1998-05-01

To establish the differential clinical characteristics between the Iatrogenic hyperthyroidism for not conventional medication for obesity treatment (weight losers) and the endogenous by Graves Basedow disease. Observational and analytical study, populational based, in the one which prospectively were compared cases with Iatrogenic hyperthyroidism (secondary to weight losers) with those with endogenous hyperthyroidism (Graves Basedow disease) as controls. Consisted of the variable clinical record of 100 correlative patients that consulted in specialized attention of endocrinology for Iatrogenic hyperthyroidism secondary to weight losers and for Graves Basedow disease. The differences observed between Iatrogenic hyperthyroidism (secondary to weight losers) (n = 43) as compared to endogenous hyperthyroidism (Graves Basedow disease) (n = 57) were: smaller age (31.8 +/- 10 as compared to 37.8 +/- 12.6 years), greater body mass index (27.6 +/- 7.2 as compared to 23.4 +/- 3.1), smaller goiter frequency (16.3% as compared to 84.2%) as well as absence of signs of ophthalmopathy (0% as compared to 57.9%). Both groups had low levels of TSH, and the difference rests in the values of free T4, low in the first group and increased in the endogenous hyperthyroidism. The odds ratio were: IMC > 27: 3.92 (0.91-16.72), age weight losers use was not selective of the first group, being detected in a 12.3% of cases of endogenous hyperthyroidism, though in periods of time remoter in relationship to the beginning of the clinic. In the differential diagnosis of a case of hyperthyroidism, it can be suspected Iatrogenic hyperthyroidism (secondary to weight losers) for medication for the obesity in patients of the feminine sex with overweight, without previous or familiar history of thyroid disease, and in those which in the physical exploration is not verified goiter neither ophthalmopathy.

Health sciences librarians, patient contact, and secondary traumatic stress.

Science.gov (United States)

Becker, Rachel W; McCrillis, Aileen

2015-04-01

The purpose of this study was to determine the prevalence of secondary traumatic stress (STS) in health sciences librarians (HSLs) who have direct contact with traumatized individuals and their families. A twenty-five-item survey and the Secondary Traumatic Stress Scale (STSS) were distributed via email to three Medical Library Association email discussion lists. A total of fifty-five HSLs responded to the survey. Survey results indicate moderate levels of STS and variability of symptoms among participants. Library and employee assistance program managers should be aware of the emotional toll of patient and/or family contact for HSLs.

Modeling secondary accidents identified by traffic shock waves.

Science.gov (United States)

Junhua, Wang; Boya, Liu; Lanfang, Zhang; Ragland, David R

2016-02-01

The high potential for occurrence and the negative consequences of secondary accidents make them an issue of great concern affecting freeway safety. Using accident records from a three-year period together with California interstate freeway loop data, a dynamic method for more accurate classification based on the traffic shock wave detecting method was used to identify secondary accidents. Spatio-temporal gaps between the primary and secondary accident were proven be fit via a mixture of Weibull and normal distribution. A logistic regression model was developed to investigate major factors contributing to secondary accident occurrence. Traffic shock wave speed and volume at the occurrence of a primary accident were explicitly considered in the model, as a secondary accident is defined as an accident that occurs within the spatio-temporal impact scope of the primary accident. Results show that the shock waves originating in the wake of a primary accident have a more significant impact on the likelihood of a secondary accident occurrence than the effects of traffic volume. Primary accidents with long durations can significantly increase the possibility of secondary accidents. Unsafe speed and weather are other factors contributing to secondary crash occurrence. It is strongly suggested that when police or rescue personnel arrive at the scene of an accident, they should not suddenly block, decrease, or unblock the traffic flow, but instead endeavor to control traffic in a smooth and controlled manner. Also it is important to reduce accident processing time to reduce the risk of secondary accident. Copyright © 2015 Elsevier Ltd. All rights reserved.

Two Cepheid variables in the Fornax dwarf galaxy

Science.gov (United States)

Light, R. M.; Armandroff, T. E.; Zinn, R.

1986-01-01

Two fields surrounding globular clusters 2 and 3 in the Fornax dwarf spheroidal galaxy have been searched for short-period variable stars that are brighter than the horizontal branch. This survey confirmed as variable the two suspected suprahorizontal-branch variables discovered by Buonanno et al. (1985) in their photometry of the clusters. The observations show that the star in cluster 2 is a W Virginis variable of 14.4 day period. It is the first W Vir variable to be found in a dwarf spheroidal galaxy, and its proximity to the center of cluster 2 suggests that it is a cluster member. The other star appears to be an anomalous Cephpeid of 0.78 day period. It lies outside or very near the boundary of cluster 3, and is therefore probably a member of the field population of Fornax. Although no other suprahorizontal-branch variables were discovered in the survey, it did confirm as variable two of the RR Lyrae candidates of Buonanno et al., which appeared at the survey limit. The implications of these observations for the understanding of the stellar content at Fornax are discussed.

An examination of the prospective association between religious service attendance and suicide: Explanatory factors and period effects.

Science.gov (United States)

Kleiman, Evan M; Liu, Richard T

2018-01-01

We addressed two unanswered questions from prior research, demonstrating a prospective association between frequent religious service attendance and decreased risk for suicide. First, we assessed whether religious service attendance conferred protection from suicide even after accounting for strength of religious affiliation. Second, we evaluated whether the relationship between religious service attendance and suicide was subject to period effects. Data were drawn from the 1978-2010 General Social Survey, a nationally representative study of 30,650 non-institutionalized, English-speaking American residents age 18 or older. Data were linked with the National Death Index through the end of 2014. We analyzed these data using moderated Cox proportional hazard analyses. Religious affiliation had no relationship with suicide. Religious service attendance only had a protective effect against suicide death among those in later (2000-2010) rather than earlier (1998 and earlier) data collection periods. Secondary analysis of data limited the types of variables that were available. The protective nature of religion is due more to participating in religious activities, such as attending religious services, than to having a strong religious affiliation, and this effect exists primarily in more recent data collection periods. Copyright © 2017 Elsevier B.V. All rights reserved.

An overview of curriculum development in the different periods of ...

African Journals Online (AJOL)

2005. ... The objective of this article is to overview the practices of elementary and secondary schools curriculum development in the different periods. ... Public and professional engagement in curriculum development is little or non-existent.

Motives of Cheating among Secondary Students: The Role of Self-Efficacy and Peer Influence

Science.gov (United States)

Nora, Wong Lok Yan; Zhang, Kaili Chen

2010-01-01

A survey research study was conducted with a sample of 100 secondary students from a local secondary school about the motives of cheating. The primary focus of this study was the interplay among variables of self-efficacy, peer influence and cheating. The results showed that students with low self-efficacy were more likely to cheat than those who…

Concurrent hypokalemic periodic paralysis and bipolar disorder

Directory of Open Access Journals (Sweden)

Chia-Lin Lin

2015-01-01

Full Text Available Primary periodic paralysis is a rare autosomal dominant disorder of ion-channel dysfunction, manifested by episodic flaccid paresis secondary to abnormal sarcolemma excitability. Membrane destabilization involving Na, K-ATPase has been hypothesized to be a biological etiology of the bipolar disorder (BD and the mechanisms underlying lithium therapy have been linked to it. To date, there has been only one reported case of BD comorbid with periodic paralysis. Herein, we reported another case of concurrent bipolar mania and hypokalemic periodic paralysis (HPP, one special form of periodic paralysis. Consistent with the previous case, our patient responded well to lithium treatment for both bipolar mania and HPP. This might provide some support to the hypothesis that the therapeutic effects of lithium in both BD and HPP could be due to the correction of the underlying common pathophysiology.

VARIABILITY IN OPTICAL SPECTRA OF ε ORIONIS

International Nuclear Information System (INIS)

Thompson, Gregory B.; Morrison, Nancy D.

2013-01-01

We present the results of a time series analysis of 130 échelle spectra of ε Ori (B0 Ia), acquired over seven observing seasons between 1998 and 2006 at Ritter Observatory. The equivalent widths of Hα (net) and He I λ5876 were measured and radial velocities were obtained from the central absorption of He I λ5876. Temporal variance spectra (TVS) revealed significant wind variability in both Hα and He I λ5876. The He I TVS have a double-peaked profile consistent with radial velocity oscillations. A periodicity search was carried out on the equivalent width and radial velocity data, as well as on wavelength-binned spectra. This analysis has revealed several periods in the variability with timescales of two to seven days. Many of these periods exhibit sinusoidal modulation in the associated phase diagrams. Several of these periods were present in both Hα and He I, indicating a possible connection between the wind and the photosphere. Due to the harmonic nature of these periods, stellar pulsations may be the origin of some of the observed variability. Periods on the order of the rotational period were also detected in the He I line in the 1998-1999 season and in both lines during the 2004-2005 season. These periods may indicate rotational modulation due to structure in the wind.

Search for variable stars in the young open cluster Stock 18

Directory of Open Access Journals (Sweden)

Sinha Tirthendu

2017-01-01

Full Text Available We have carried out multi-epoch deep I band photometry of the open cluster Stock 18 to search for variable stars in star forming regions. In the present study, we report identification of 28 periodic and 165 non-periodic variables stars. The periods of most of the periodic variables are in between 2 to 20 hours and their magnitude varies between 0.05 to 0.6 mag. We have derived spectral energy distributions for 48 probable pre-main sequence variables and the average age and mass is found to be 2.7 ± 0.3 Myrs and 2.7 ± 0.2 M⊙, respectively.

[Modulator effect of socio-emotional variables on training in elaboration strategies in Compulsory Secondary Education (CSE): paraphrase and applications].

Science.gov (United States)

Martín-Antón, Luis Jorge; Carbonero Martín, Miguel Angel; Román Sánchez, José María

2012-02-01

The purpose of this work is to verify the modulation of motivation, self-concept, and causal attributions in the efficacy of a training program of strategies to elaborate information in the stage of Compulsory Secondary Education (CSE). We selected 328 students from CSE, 179 from second grade and 149 from fourth grade, and three measurement moments: pretest, posttest, and follow-up. The results indicate greater use of learning strategies by students with higher intrinsic motivation, in contrast to students with higher extrinsic motivation, who use learning strategies less frequently. With regard to self-concept, the results differ as a function of the course. In second grade, we found modulation of the variable Academic self-concept, whereas in fourth grade, such modulation is produced by General self-concept and Private self-concept. In general, there is a tendency towards more enduring significant improvements in students with medium and high self-concept, especially in their perception of the use of strategies or in complex tasks that involve relating the contents to be learned with experiences from their daily life. However, students with low self-concept significantly improve strategies associated with learning how to perform specific tasks.

Ecotype variability in growth and secondary metabolite profile in Moringa oleifera: impact of sulfur and water availability.

Science.gov (United States)

Förster, Nadja; Ulrichs, Christian; Schreiner, Monika; Arndt, Nick; Schmidt, Reinhard; Mewis, Inga

2015-03-25

Moringa oleifera is widely cultivated in plantations in the tropics and subtropics. Previous cultivation studies with M. oleifera focused primarily only on leaf yield. In the present study, the content of potentially health-promoting secondary metabolites (glucosinolates, phenolic acids, and flavonoids) were also investigated. Six different ecotypes were grown under similar environmental conditions to identify phenotypic differences that can be traced back to the genotype. The ecotypes TOT4880 (origin USA) and TOT7267 (origin India) were identified as having the best growth performance and highest secondary metabolite production, making them an ideal health-promoting food crop. Furthermore, optimal cultivation conditions-exemplarily on sulfur fertilization and water availability-for achieving high leaf and secondary metabolite yields were investigated for M. oleifera. In general, plant biomass and height decreased under water deficiency compared to normal cultivation conditions, whereas the glucosinolate content increased. The effects depended to a great extent on the ecotype.

Teacher quality and quantity as correlates of secondary school ...

African Journals Online (AJOL)

This study investigated the twin variables of quality and quantity of teachers as correlates of secondary school academic performance in Ogun State of Nigeria between 1997/98 and 2000/2001 academic sessions. The study was conducted ex-post facto under a descriptive survey research design using the proportional to ...

VARIABLE STARS IN THE GLOBULAR CLUSTER NGC 2808

International Nuclear Information System (INIS)

Kunder, Andrea; Walker, Alistair R.; Stetson, Peter B.; Catelan, Márcio; Amigo, Pía

2013-01-01

The first calibrated broadband BVI time-series photometry is presented for the variable stars in NGC 2808, with observations spanning a range of 28 years. We have also redetermined the variability types and periods for the variable stars identified previously by Corwin et al., revising the number of probable fundamental-mode RR Lyrae variables (RR0) to 11 and the number of first-overtone variables (RR1) to five. Our observations were insufficient to discern the nature of the previously identified RR1 star, V24, and the tentatively identified RR1 star, V13. These two variables are ∼0.8 mag brighter than the RR Lyrae variables, appear to have somewhat erratic period and/or luminosity changes, and lie inside the RR Lyrae instability strip. Curiously, all but one of the RR Lyrae stars studied in this relatively metal-rich cluster exhibit the Blazhko phenomenon, an effect thought to occur with higher frequency in metal-poor environments. The mean periods of the RR0 and RR1 variables are (P) RR0 = 0.56 ± 0.01 d and RR1 = 0.30 ± 0.02 d, respectively, supporting an Oosterhoff I classification of the cluster. On the other hand, the number ratio of RR1-to-RR0-type variables is high, though not unprecedented, for an Oosterhoff I cluster. The RR Lyrae variables have no period shifts at a given amplitude compared to the M3 variables, making it unlikely that these variables are He enhanced. Using the recent recalibration of the RR Lyrae luminosity scale by Catelan and Cortés, a mean distance modulus of (m – M) V = 15.57 ± 0.13 mag for NGC 2808 is obtained, in good agreement with that determined here from its type II Cepheid and SX Phoenicis population. Our data have also allowed the discovery of two new candidate SX Phoenicis stars and an eclipsing binary in the blue straggler region of the NGC 2808 color-magnitude diagram.

ROTSE All-Sky Surveys for Variable Stars. I. Test Fields

International Nuclear Information System (INIS)

Akerlof, C.; Amrose, S.; Balsano, R.; Bloch, J.; Casperson, D.; Fletcher, S.; Gisler, G.; Hills, J.; Kehoe, R.; Lee, B.

2000-01-01

The Robotic Optical Transient Search Experiment I (ROTSE-I) experiment has generated CCD photometry for the entire northern sky in two epochs nightly since 1998 March. These sky patrol data are a powerful resource for studies of astrophysical transients. As a demonstration project, we present first results of a search for periodic variable stars derived from ROTSE-I observations. Variable identification, period determination, and type classification are conducted via automatic algorithms. In a set of nine ROTSE-I sky patrol fields covering roughly 2000 deg2, we identify 1781 periodic variable stars with mean magnitudes between m v = 10.0 and m v = 15.5. About 90% of these objects are newly identified as variable. Examples of many familiar types are presented. All classifications for this study have been manually confirmed. The selection criteria for this analysis have been conservatively defined and are known to be biased against some variable classes. This preliminary study includes only 5.6% of the total ROTSE-I sky coverage, suggesting that the full ROTSE-I variable catalog will include more than 32,000 periodic variable stars. (c) (c) 2000. The American Astronomical Society

Variables affecting viral plaque formation in microculture plaque assays using homologous antibody in a liquid overlay.

Science.gov (United States)

Randhawa, A S; Stanton, G J; Green, J A; Baron, S

1977-05-01

A liquid antibody microculture plaque assay and the variables that govern its effectiveness are described. The assay is based on the principle that low concentrations of homologous antibody can inhibit secondary plaque formation without inhibiting formation of primary plaques. Thus, clear plaques that followed a linear dose response were produced. The assay was found to be more rapid, less cumbersome, and less expensive than assays using agar overlays and larger tissue culture plates. It was reproducible, quantitative, and had about the same sensitivity as the agar overlay technique in measuring infectious coxsackievirus type B-3. It was more sensitive in assaying adenovirus type 3 and Western equine encephalomyelitis, vesicular stomatitis, Semliki forest, Sendai, Sindbis, and Newcastle disease viruses than were liquid, carboxymethylcellulose, and methylcellulose microculture plaque assays. The variables influencing sensitivity and accuracy, as determined by using coxsackievirus type B-3, were: (i) the inoculum volume of virus; (ii) the incubation period of virus; and (iii) the incubation temperature.

Absent menstrual periods - secondary

Science.gov (United States)

... tumors Drugs for cancer treatment Drugs to treat schizophrenia or psychosis Overactive thyroid gland Polycystic ovarian syndrome ... can include: Breast size changes Weight gain or weight loss Discharge from the breast or change in breast ...

The influence of selected teacher inputs on students’ academic achievement in the junior secondary school certificate mathematics in Namibia

Directory of Open Access Journals (Sweden)

Simon E. Akpo

2013-12-01

Full Text Available This study explored the link between teachers’ inputs and students’ academic achievement in the JSC Mathematics for the period 2006 to 2010. One hundred and fifty secondary schools selected from 573 secondary schools in the country constituted the target population. One hundred and sixty-four JSC mathematics teachers from the 150 secondary schools participated in the study, with the final JSC Mathematics results of the students serving as the dependent variable of the study. Mathematics teachers’ input data (academic qualifications, teaching experience and subject specialisation were collected from a questionnaire developed by the researchers. Standard multiple regression was used to analyse the link between teachers’ inputs and students’ academic achievement in JSC Mathematics at P < 0.05and P < 0.10 respectively. The study found that teachers’ academic qualifications and subject specialisation had a significant and positive relationship with students’ academic achievement in JSC Mathematics. Teachers’ gender, however, was not significantly related to students’ academic achievement in JSC Mathematics. This is the first time within the Namibian context that we have empirically demonstrated the link between teachers’ inputs and students’ academic achievement in JSC Mathematics. The study therefore provides support for the policy initiatives that seek to link teachers’ academic qualifications, subject specialisation and teaching experience to employment and classroom allocation.

Phenology of seed and leaves rain in response to periodic climatic variability in a seasonal wet tropical forest

Science.gov (United States)

Matteo, D.; Wright, S. J.; Davies, S. J.; Muller-Landau, H. C.; Wolfe, B.; Detto, M.

2016-12-01

Phenology, by controlling the rhythms of plants, plays a fundamental role in regulating access to resources, ecosystem processes, competition among species, interactions with consumers and feedbacks to the climate. In high biodiverse tropical forests, where phenology of flowering and leafing are complex, an adequate representation of phenology must take into account a given set of climatic, edaphic and biotic factors. Climatic factors are particularly important because plants may use them as cues for timing different phenological phases and be influenced by their intensity. Climatic variability can be periodic, if events occur with regular frequency, or aperiodic. One prominent periodic large-scale pattern that causes unusual weather is ENSO event. In general, Central America tends to be dry and warm during a mature phase of an ENSO event, which usually peaks between October and January with a frequency of 2-3 events per decade. Because in many tropical areas the effect of ENSO is highly prominent, it is plausible that plants have adapted their growth and reproduction mechanisms to synchronize ENSO phases, in a similar way that plants do during the seasonal cycle. We used a long dataset (30+ years) of fruits and leaves rains of tropical trees and lianas to determine ecosystem response and species specific response of these phenological events to local climate variability corresponding to the modes of ENSO. Specifically, we tested the hypothesis that phenological responses to ENSO are similar to response to seasonal cycles, i.e., higher litterfall before a warm-dry phase and higher fruiting after such phase, with strong correlation between seeds and leaves. At sub-community level, we evaluated whether evergreen and deciduous, biotic and abiotic dispersers and free and climbing life forms, have the same response to ENSO in terms of leaves and seeds rain. At species level we tested the hypothesis that species with low photosynthetic capacity leaves are more responsive

Period Variations for the Cepheid VZ Cyg

Science.gov (United States)

Sirorattanakul, Krittanon; Engle, Scott; Pepper, Joshua; Wells, Mark; Laney, Clifton D.; Rodriguez, Joseph E.; Stassun, Keivan G.

2017-12-01

The Cepheid Period-Luminosity law is a key rung on the extragalactic distance ladder. However, numerous Cepheids are known to undergo period variations. Monitoring, refining, and understanding these period variations allows us to better determine the parameters of the Cepheids themselves and of the instability strip in which they reside, and to test models of stellar evolution. VZ Cyg, a classical Cepheid pulsating at ˜4.864 days, has been observed for over 100 years. Combining data from literature observations, the Kilodegree Extremely Little Telescope (KELT) transit survey, and new targeted observations with the Robotically Controlled Telescope (RCT) at Kitt Peak, we find a period change rate of dP/dt = -0.0642 ± 0.0018 s yr-1. However, when only the recent observations are examined, we find a much higher period change rate of dP/dt = -0.0923 ± 0.0110 s yr-1. This higher rate could be due to an apparent long-term (P ≈ 26.5 years) cyclic period variation. The possible interpretations of this single Cepheid’s complex period variations underscore both the need to regularly monitor pulsating variables and the important benefits that photometric surveys such as KELT can have on the field. Further monitoring of this interesting example of Cepheid variability is recommended to confirm and better understand the possible cyclic period variations. Further, Cepheid timing analyses are necessary to fully understand their current behaviors and parameters, as well as their evolutionary histories.

Analysis of the optical emission of the young precataclysmic variables HS 1857+5144 and ABELL 65

Science.gov (United States)

Shimansky, V. V.; Pozdnyakova, S. A.; Borisov, N. V.; Bikmaev, I. F.; Vlasyuk, V. V.; Spiridonova, O. I.; Galeev, A. I.; Mel'Nikov, S. S.

2009-10-01

We analyze the physical state and the properties of the close binary systems HS 1857+5144 and Abell 65. We took the spectra of both systems over a wide range of orbital phases with the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences (SAO RAS) and obtained their multicolor light curves with the RTT150 and Zeiss-1000 telescopes of the SAO RAS. We demonstrate that both Abell 65 and HS 1857+5144 are young precataclysmic variables (PV) with orbital periods of P orb = 1. d 003729 and P orb = 0. d 26633331, respectively. The observed brightness and spectral variations during the orbital period are due to the radiation of the cold component, which absorbs the short-wave radiation of the hot component and reemits it in the visual part of the spectrum. A joint analysis of the brightness and radial velocity curves allowed us to find the possible and optimum sets of their fundamental parameters. We found the luminosity excesses of the secondary components of HS 1857+5144 and Abell 65 with respect to the corresponding Main Sequence stars to be typical for such objects. The excess luminosities of the secondary components of all young PVs are indicative of their faster relaxation rate towards the quiescent state compared to the rates estimated in earlier studies.

Business Studies Academic Performance Differences of Secondary School Juniors in Akwa Ibom State of Nigeria

Science.gov (United States)

Udoukpong, Bassey E.; Emah, Ime E.; Umoren, Shirley E.

2012-01-01

The research examined the differences in the academic performance in Business Studies of a sampled secondary school junior students in Akwa Ibom State of Nigeria. A sample of 290 (138 male and 152 female) Junior Secondary Three (9th grade) students was surveyed. The students' variables' being examined vis-à-vis academic performance in Business…

The WFCAM multiwavelength Variable Star Catalog

Science.gov (United States)

Ferreira Lopes, C. E.; Dékány, I.; Catelan, M.; Cross, N. J. G.; Angeloni, R.; Leão, I. C.; De Medeiros, J. R.

2015-01-01

Context. Stellar variability in the near-infrared (NIR) remains largely unexplored. The exploitation of public science archives with data-mining methods offers a perspective for a time-domain exploration of the NIR sky. Aims: We perform a comprehensive search for stellar variability using the optical-NIR multiband photometric data in the public Calibration Database of the WFCAM Science Archive (WSA), with the aim of contributing to the general census of variable stars and of extending the current scarce inventory of accurate NIR light curves for a number of variable star classes. Methods: Standard data-mining methods were applied to extract and fine-tune time-series data from the WSA. We introduced new variability indices designed for multiband data with correlated sampling, and applied them for preselecting variable star candidates, i.e., light curves that are dominated by correlated variations, from noise-dominated ones. Preselection criteria were established by robust numerical tests for evaluating the response of variability indices to the colored noise characteristic of the data. We performed a period search using the string-length minimization method on an initial catalog of 6551 variable star candidates preselected by variability indices. Further frequency analysis was performed on positive candidates using three additional methods in combination, in order to cope with aliasing. Results: We find 275 periodic variable stars and an additional 44 objects with suspected variability with uncertain periods or apparently aperiodic variation. Only 44 of these objects had been previously known, including 11 RR Lyrae stars on the outskirts of the globular cluster M 3 (NGC 5272). We provide a preliminary classification of the new variable stars that have well-measured light curves, but the variability types of a large number of objects remain ambiguous. We classify most of the new variables as contact binary stars, but we also find several pulsating stars, among which

Nonlinear periodic waves in dusty plasma with variable dust charge

International Nuclear Information System (INIS)

Yadav, Lakhan Lal; Bharuthram, R.

2002-01-01

Using the reductive perturbation method, we present a theory of nonlinear periodic waves, viz. the cnoidal waves, in a dusty plasma consisting of electrons, ions, and cold dust grains with charge fluctuations, which in the limiting case reduce to dust acoustic solitons. It is found that the frequency of the dust acoustic cnoidal wave increases with its amplitude. The dust charge fluctuations are found to affect the characteristics of the cnoidal waves

The Medieval Warm Period, the Little Ice Age and simulated climatic variability

Energy Technology Data Exchange (ETDEWEB)

Hunt, B.G. [CSIRO Marine and Atmospheric Research, Aspendale, VIC (Australia)

2006-12-15

The CSIRO Mark 2 coupled global climatic model has been used to generate a 10,000-year simulation for 'present' climatic conditions. The model output has been analysed to identify sustained climatic fluctuations, such as those attributed to the Medieval Warm Period (MWP) and the Little Ice Age (LIA). Since no external forcing was permitted during the model run all such fluctuations are attributed to naturally occurring climatic variability associated with the nonlinear processes inherent in the climatic system. Comparison of simulated climatic time series for different geographical locations highlighted the lack of synchronicity between these series. The model was found to be able to simulate climatic extremes for selected observations for century timescales, as well as identifying the associated spatial characteristics. Other examples of time series simulated by the model for the USA and eastern Russia had similar characteristics to those attributed to the MWP and the LIA, but smaller amplitudes, and clearly defined spatial patterns. A search for the frequency of occurrence of specified surface temperature anomalies, defined via duration and mean value, revealed that these were primarily confined to polar regions and northern latitudes of Europe, Asia and North America. Over the majority of the oceans and southern hemisphere such climatic fluctuations could not be sustained, for reasons explained in the paper. Similarly, sustained sea-ice anomalies were mainly confined to the northern hemisphere. An examination of mechanisms associated with the sustained climatic fluctuations failed to identify a role for the North Atlantic Oscillation, the El Nino-Southern Oscillation or the Pacific Decadal Oscillation. It was therefore concluded that these fluctuations were generated by stochastic processes intrinsic to the nonlinear climatic system. While a number of characteristics of the MWP and the LIA could have been partially caused by natural processes within

Secondary Hypertension

Science.gov (United States)

Secondary hypertension Overview Secondary hypertension (secondary high blood pressure) is high blood pressure that's caused by another medical condition. Secondary hypertension can be caused by conditions that affect your kidneys, ...

Period multiplication and chaotic phenomena in atmospheric dielectric-barrier glow discharges

International Nuclear Information System (INIS)

Wang, Y. H.; Zhang, Y. T.; Wang, D. Z.; Kong, M. G.

2007-01-01

In this letter, evidence of temporal plasma nonlinearity in which atmospheric dielectric-barrier discharges undergo period multiplication and chaos using a one-dimensional fluid model is reported. Under the conditions conducive for chaotic states, several frequency windows are identified in which period multiplication and secondary bifurcations are observed. Such time-domain nonlinearity is important for controlling instabilities in atmospheric glow discharges

Long-period variables in the Magellanic Clouds: Supergiants, AGB stars, supernova precursors, planetary nebula precursors, and enrichment of the interstellar medium

International Nuclear Information System (INIS)

Wood, P.; Bessell, M.S.; Fox, M.W.

1983-01-01

Infrared JHK magnitudes and low-dispersion red spectra have been obtained for 90 long-period variables (LPVs) in the Small and Large Magellanic Clouds. The LPVs fall into two distinct groups, core helium (or carbon) burning supergiants and stars on the asymptotic giant branch (AGB). The supergiants have small pulsation amplitudes in K ( or approx. =5 M/sub sun/ produce supernovae while less massive stars produce planetary nebulae with nebula masses from approx.0.1--2.1 M/sub sun/. The coreburning red supergiants appear highly overluminous for their pulsation mass, indicating that they have lost up to half their mass since the main-sequence phase

Tannat grape composition responses to spatial variability of temperature in an Uruguay's coastal wine region

Science.gov (United States)

Fourment, Mercedes; Ferrer, Milka; González-Neves, Gustavo; Barbeau, Gérard; Bonnardot, Valérie; Quénol, Hervé

2017-09-01

Spatial variability of temperature was studied in relation to the berry basic composition and secondary compounds of the Tannat cultivar at harvest from vineyards located in Canelones and Montevideo, the most important wine region of Uruguay. Monitoring of berries and recording of temperature were performed in 10 commercial vineyards of Tannat situated in the southern coastal wine region of the country for three vintages (2012, 2013, and 2014). Results from a multivariate correlation analysis between berry composition and temperature over the three vintages showed that (1) Tannat responses to spatial variability of temperature were different over the vintages, (2) correlations between secondary metabolites and temperature were higher than those between primary metabolites, and (3) correlation values between berry composition and climate variables increased when ripening occurred under dry conditions (below average rainfall). For a particular studied vintage (2013), temperatures explained 82.5% of the spatial variability of the berry composition. Daily thermal amplitude was found to be the most important spatial mode of variability with lower values recorded at plots nearest to the sea and more exposed to La Plata River. The highest levels in secondary compounds were found in berries issued from plots situated as far as 18.3 km from La Plata River. The increasing knowledge of temperature spatial variability and its impact on grape berry composition contributes to providing possible issues to adapt grapevine to climate change.

YSOVAR: MID-INFRARED VARIABILITY IN NGC 1333

Energy Technology Data Exchange (ETDEWEB)

Rebull, L. M. [Infrared Science Archive (IRSA), Infrared Processing and Analysis Center (IPAC), 1200 E. California Blvd., California Institute of Technology, Pasadena, CA 91125 (United States); Stauffer, J. R.; Cody, A. M. [Spitzer Science Center (SSC), 1200 E. California Blvd., California Institute of Technology, Pasadena, CA 91125 (United States); Günther, H. M.; Poppenhaeger, K.; Wolk, S. J.; Hora, J.; Forbrich, J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Hillenbrand, L. A. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Hernandez, J. [Centro de Investigaciones de Astronomía, Apdo. Postal 264, Mérida 5101-A (Venezuela, Bolivarian Republic of); Bayo, A. [Max Planck Institut für Astronomie, Königstuhl 17, D-69117, Heidelberg (Germany); Covey, K. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Gutermuth, R. [Dept. of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Morales-Calderón, M.; Bouy, H. [Depto. Astrofísica, Centro de Astrobiología (INTA-CSIC), ESAC campus, P.O. Box 78, E-28691 Villanueva de la Cañada (Spain); Plavchan, P. [NASA Exoplanet Science Institute (NExScI), Infrared Processing and Analysis Center (IPAC), 1200 E. California Blvd., California Institute of Technology, Pasadena, CA 91125 (United States); Song, I. [Physics and Astronomy Department, University of Georgia, Athens, GA 30602-2451 (United States); Terebey, S., E-mail: rebull@ipac.caltech.edu [Department of Physics and Astronomy, 5151 State University Drive, California State University at Los Angeles, Los Angeles, CA 90032 (United States); and others

2015-12-15

As part of the Young Stellar Object VARiability (YSOVAR) program, we monitored NGC 1333 for ∼35 days at 3.6 and 4.5 μm using the Spitzer Space Telescope. We report here on the mid-infrared variability of the point sources in the ∼10′ × ∼20′ area centered on 03:29:06, +31:19:30 (J2000). Out of 701 light curves in either channel, we find 78 variables over the YSOVAR campaign. About half of the members are variable. The variable fraction for the most embedded spectral energy distributions (SEDs) (Class I, flat) is higher than that for less embedded SEDs (Class II), which is in turn higher than the star-like SEDs (Class III). A few objects have amplitudes (10–90th percentile brightness) in [3.6] or [4.5] > 0.2 mag; a more typical amplitude is 0.1–0.15 mag. The largest color change is >0.2 mag. There are 24 periodic objects, with 40% of them being flat SED class. This may mean that the periodic signal is primarily from the disk, not the photosphere, in those cases. We find 9 variables likely to be “dippers,” where texture in the disk occults the central star, and 11 likely to be “bursters,” where accretion instabilities create brightness bursts. There are 39 objects that have significant trends in [3.6]–[4.5] color over the campaign, about evenly divided between redder-when-fainter (consistent with extinction variations) and bluer-when-fainter. About a third of the 17 Class 0 and/or jet-driving sources from the literature are variable over the YSOVAR campaign, and a larger fraction (∼half) are variable between the YSOVAR campaign and the cryogenic-era Spitzer observations (6–7 years), perhaps because it takes time for the envelope to respond to changes in the central source. The NGC 1333 brown dwarfs do not stand out from the stellar light curves in any way except there is a much larger fraction of periodic objects (∼60% of variable brown dwarfs are periodic, compared to ∼30% of the variables overall)

Elemental GCR Observations during the 2009-2010 Solar Minimum Period

Science.gov (United States)

Lave, K. A.; Israel, M. H.; Binns, W. R.; Christian, E. R.; Cummings, A. C.; Davis, A. J.; deNolfo, G. A.; Leske, R. A.; Mewaldt, R. A.; Stone, E. C.;

Pulsations and period changes of the non-Blazhko RR lyrae variable Y oct observed from Dome A, Antarctica

Energy Technology Data Exchange (ETDEWEB)

Zhihua, Huang; Jianning, Fu; Weikai, Zong; Lingzhi, Wang; Zonghong, Zhu [Department of Astronomy, Beijing Normal University, Beijing 100875 (China); M, Macri Lucas; Lifan, Wang [Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX (United States); Ashley, Michael C. B.; S, Lawrence Jon; Daniel, Luong-Van [School of Physics, University of New South Wales, NSW (Australia); Xiangqun, Cui; Long-Long, Feng; Xuefei, Gong; Qiang, Liu; Huigen, Yang; Xiangyan, Yuan; Xu, Zhou; Zhenxi, Zhu [Chinese Center for Antarctic Astronomy, Nanjing (China); R, Pennypacker Carl [Center for Astrophysics, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); G, York Donald, E-mail: jnfu@bnu.edu.cn [Department of Astronomy and Astrophysics and Enrico Fermi Institute, University of Chicago, Chicago, IL (United States)

2015-01-01

During the operation of the Chinese Small Telescope Array (CSTAR) in Dome A of Antarctica in the years 2008, 2009, and 2010, large amounts of photometric data have been obtained for variable stars in the CSTAR field. We present here the study of one of six RR Lyrae variables, Y Oct, observed with CSTAR in Dome A, Antarctica. Photometric data in the i band were obtained in 2008 and 2010, with a duty cycle (defined as the fraction of time representing scientifically available data to CSTAR observation time) of about 44% and 52%, respectively. In 2009, photometric data in the g and r bands were gathered for this star, with a duty cycle of 65% and 60%, respectively. Fourier analysis of the data in the three bands only shows the fundamental frequency and its harmonics, which is characteristic of the non-Blazhko RR Lyrae variables. Values of the fundamental frequency and the amplitudes, as well as the total pulsation amplitude, are obtained from the data in the three bands separately. The amplitude of the fundamental frequency and the total pulsation amplitude in the g band are the largest, and those in the i band the smallest. Two-hundred fifty-one times of maximum are obtained from the three seasons of data, which are analyzed together with 38 maximum times provided in the GEOS RR Lyrae database. A period change rate of −0.96 ± 0.07 days Myr{sup −1} is then obtained, which is a surprisingly large negative value. Based on relations available in the literature, the following physical parameters are derived: [Fe/H] = −1.41 ± 0.14, M{sub V} = 0.696 ± 0.014 mag, V−K = 1.182 ± 0.028 mag, logT{sub eff} = 3.802 ± 0.003 K, logg = 2.705 ± 0.004, logL/L{sub ⊙} = 1.625 ± 0.013, and logM/M{sub ⊙} = −0.240 ± 0.019.

Periodic solutions for one dimensional wave equation with bounded nonlinearity

Science.gov (United States)

Ji, Shuguan

2018-05-01

This paper is concerned with the periodic solutions for the one dimensional nonlinear wave equation with either constant or variable coefficients. The constant coefficient model corresponds to the classical wave equation, while the variable coefficient model arises from the forced vibrations of a nonhomogeneous string and the propagation of seismic waves in nonisotropic media. For finding the periodic solutions of variable coefficient wave equation, it is usually required that the coefficient u (x) satisfies ess infηu (x) > 0 with ηu (x) = 1/2 u″/u - 1/4 (u‧/u)2, which actually excludes the classical constant coefficient model. For the case ηu (x) = 0, it is indicated to remain an open problem by Barbu and Pavel (1997) [6]. In this work, for the periods having the form T = 2p-1/q (p , q are positive integers) and some types of boundary value conditions, we find some fundamental properties for the wave operator with either constant or variable coefficients. Based on these properties, we obtain the existence of periodic solutions when the nonlinearity is monotone and bounded. Such nonlinearity may cross multiple eigenvalues of the corresponding wave operator. In particular, we do not require the condition ess infηu (x) > 0.

Crisis-induced unstable dimension variability in a dynamical system

International Nuclear Information System (INIS)

Kubo, Geraldo T.; Viana, Ricardo L.; Lopes, Sergio R.; Grebogi, Celso

2008-01-01

Unstable dimension variability is an extreme form of non-hyperbolic behavior in chaotic systems whose attractors have periodic orbits with a different number of unstable directions. We propose a new mechanism for the onset of unstable dimension variability based on an interior crisis, or a collision between a chaotic attractor and an unstable periodic orbit. We give a physical example by considering a high-dimensional dissipative physical system driven by impulsive periodic forcing

Secondary plant succession on disturbed sites at Yucca Mountain, Nevada

Energy Technology Data Exchange (ETDEWEB)

Angerer, J.P.; Ostler, W.K.; Gabbert, W.D.; Schultz, B.W.

1994-12-01

This report presents the results of a study of secondary plant succession on disturbed sites created during initial site investigations in the late 1970s and early 1980s at Yucca Mountain, NV. Specific study objectives were to determine the rate and success of secondary plant succession, identify plant species found in disturbances that may be suitable for site-specific reclamation, and to identify environmental variables that influence succession on disturbed sites. During 1991 and 1992, fifty seven disturbed sites were located. Vegetation parameters, disturbance characteristics and environmental variables were measured at each site. Disturbed site vegetation parameters were compared to that of undisturbed sites to determine the status of disturbed site plant succession. Vegetation on disturbed sites, after an average of ten years, was different from undisturbed areas. Ambrosia dumosa, Chrysothamnus teretifolius, Hymenoclea salsola, Gutierrezia sarothrae, Atriplex confertifolia, Atriplex canescens, and Stephanomeria pauciflora were the most dominant species across all disturbed sites. With the exception of A. dumosa, these species were generally minor components of the undisturbed vegetation. Elevation, soil compaction, soil potassium, and amounts of sand and gravel in the soil were found to be significant environmental variables influencing the species composition and abundance of perennial plants on disturbed sites. The recovery rate for disturbed site secondary succession was estimated. Using a linear function (which would represent optimal conditions), the recovery rate for perennial plant cover, regardless of which species comprised the cover, was estimated to be 20 years. However, when a logarithmic function (which would represent probable conditions) was used, the recovery rate was estimated to be 845 years. Recommendations for future studies and site-specific reclamation of disturbances are presented.

Secondary plant succession on disturbed sites at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Angerer, J.P.; Ostler, W.K.; Gabbert, W.D.; Schultz, B.W.

1994-12-01

This report presents the results of a study of secondary plant succession on disturbed sites created during initial site investigations in the late 1970s and early 1980s at Yucca Mountain, NV. Specific study objectives were to determine the rate and success of secondary plant succession, identify plant species found in disturbances that may be suitable for site-specific reclamation, and to identify environmental variables that influence succession on disturbed sites. During 1991 and 1992, fifty seven disturbed sites were located. Vegetation parameters, disturbance characteristics and environmental variables were measured at each site. Disturbed site vegetation parameters were compared to that of undisturbed sites to determine the status of disturbed site plant succession. Vegetation on disturbed sites, after an average of ten years, was different from undisturbed areas. Ambrosia dumosa, Chrysothamnus teretifolius, Hymenoclea salsola, Gutierrezia sarothrae, Atriplex confertifolia, Atriplex canescens, and Stephanomeria pauciflora were the most dominant species across all disturbed sites. With the exception of A. dumosa, these species were generally minor components of the undisturbed vegetation. Elevation, soil compaction, soil potassium, and amounts of sand and gravel in the soil were found to be significant environmental variables influencing the species composition and abundance of perennial plants on disturbed sites. The recovery rate for disturbed site secondary succession was estimated. Using a linear function (which would represent optimal conditions), the recovery rate for perennial plant cover, regardless of which species comprised the cover, was estimated to be 20 years. However, when a logarithmic function (which would represent probable conditions) was used, the recovery rate was estimated to be 845 years. Recommendations for future studies and site-specific reclamation of disturbances are presented

Dropout in the lower tracks of Dutch secondary education : Predictor variables and variation among schools

NARCIS (Netherlands)

Luyten, H; Bosker, R.J.; Dekkers, H; Derks, A

2003-01-01

This study analyses the data from a large-scale longitudinal investigation into the effect of both school and student characteristics on the dropout rate for students in lower secondary education in The Netherlands. Dropout rates were found to vary significantly between schools, but only a single

Personality traits as predictors of depression, anxiety, and stress with secondary school students of final years

Directory of Open Access Journals (Sweden)

Vujičić Milena M.

2017-01-01

Full Text Available The main aim of this research is to examine the predictive power of personality traits, as defined by the Big five model of personality in expressing depression, anxiety, and stress with secondary school students of final years. The research was conducted on a sample of 977 secondary school students in the third and fourth grade from ten secondary schools in Niš. The gender structure of the sample was as follows: 397 boys and 607 girls. The following instruments were used in the research: Depression Anxiety Stress Scales (DASS-21; Lovibond and Lovibond, 1995, Big Five Inventory - BFI (John, Donahue and Kentle, 1991. The results showed that the regression model constructed by personal traits (Extraversion, Agreeableness, Conscientiousness, Neuroticism, and Openness to experience explain 26% of the criterion variable of Anxiety. The largest individual contribution to the prediction of this variable is achieved by the personal trait Neuroticism (β=.34, p<0.01 . Other personal traits that contribute to the prediction of this variable at a statistically significant level are Extraversion (β =-.17, p<0.01, Agreeableness (β =-.14, p<0.01 and Conscientiousness (β =-.17, p<0.01. The same model explains 37% of the criterion variable Stress. The largest individual contribution to Stress prediction is achieved by the personal trait Neuroticism (β =.57, p<0.01. The same model explains 27% of the criterion variable Anxiety as well. The largest individual contribution to the prediction of this variable is achieved by the personal trait Neuroticism (β =.45, p<0.01, whereas a statistically significant correlation between personal traits Agreeableness (β =-.06, p<0.05 and Conscientious (β =-.12, p<0.01 exists. Results show that the difference between boys and girls in expressing Anxiety (t=-2.96, p<0.01 and Stress (t=-5.01, p<0.01 exists. These emotional states are more expressive with girls. However, there are no differences in expressing Depression

Effects of ICT Assisted Real and Virtual Learning on the Performance of Secondary School Students

Science.gov (United States)

Deka, Monisha; Jena, Ananta Kumar

2017-01-01

The study aimed to assess the effect of ICT assisted real and virtual learning performance over the traditional approach of secondary school students. Non-Equivalent Pretest-Posttest Quasi Experimental Design used to assess and relate the effects of independent variables virtual learning on dependent variables (i.e. learning performance).…

Direct radiative feedback due to biogenic secondary organic aerosol estimated from boreal forest site observations

International Nuclear Information System (INIS)

Lihavainen, Heikki; Asmi, Eija; Aaltonen, Veijo; Makkonen, Ulla; Kerminen, Veli-Matti

2015-01-01

We used more than five years of continuous aerosol measurements to estimate the direct radiative feedback parameter associated with the formation of biogenic secondary organic aerosol (BSOA) at a remote continental site at the edge of the boreal forest zone in Northern Finland. Our upper-limit estimate for this feedback parameter during the summer period (ambient temperatures above 10 °C) was −97 ± 66 mW m −2 K −1 (mean ± STD) when using measurements of the aerosol optical depth (f AOD ) and −63 ± 40 mW m −2 K −1 when using measurements of the ‘dry’ aerosol scattering coefficient at the ground level (f σ ). Here STD represents the variability in f caused by the observed variability in the quantities used to derive the value of f. Compared with our measurement site, the magnitude of the direct radiative feedback associated with BSOA is expected to be larger in warmer continental regions with more abundant biogenic emissions, and even larger in regions where biogenic emissions are mixed with anthropogenic pollution. (letter)

Predictors of Secondary Traumatic Stress among Children's Advocacy Center Forensic Interviewers

Science.gov (United States)

Bonach, Kathryn; Heckert, Alex

2012-01-01

This study examined various predictor variables that were hypothesized to impact secondary traumatic stress in forensic interviewers (n = 257) from children's advocacy centers across the United States. Data were examined to investigate the relationship between organizational satisfaction, organizational buffers, and job support with secondary…

DESIGNING EDUCATIONAL PROCESS OF FORMING SOCIAL AND PEDAGOGICAL COMPETENCE OF FUTURE PRIMARY SCHOOL TEACHERS IN INCLUSIVE SECONDARY SCHOOL

Directory of Open Access Journals (Sweden)

Zoia Shevtsiv

2017-04-01

Full Text Available The article is devoted to the issue of social and pedagogical competence of future primary school teacher in inclusive secondary schools. The aim of the article is to define the concept “design” and “pedagogical design”; to disclose methodological approaches and main features of pedagogical design of forming of social and pedagogical competence of future primary school teacher in inclusive secondary schools; to identify structural elements of social and pedagogical competence. The article analyzes the essence of the concept “design”. The process of designing educational system of social and pedagogical competence of future primary school teacher in inclusive secondary school is based on several interrelated methodological approaches, including systematic, axiological, active, person-centered, contextual acmeological, and competential ones. Important factors and theoretical starting positions are designing general principles of education: humanism and democracy; principles of teaching, scientific, professional orientation, integrity, communication theory and practice, consistency and systematic, variability, pedagogical creativity. The special principles are the following: problematic, technologizing, dialogization, and competence ones. Social and pedagogical competence of future primary school teachers in inclusive secondary school is structured by the cognitive, active, professional and personal components. Structure components are defined as a synthesis of social and pedagogical competences, educational and developmental, communicative, diagnostic, organizational, predictive, preventive, security and defense, correctional and rehabilitation, adaptation items. Established continuity of the educational process of forming social and pedagogical competence of future primary school teacher in inclusive secondary school takes place during the period of study in higher education establishments. The following conclusions are drawn that

ASSESSING GLOBAL CLIMATE VARIABILITY UNDER COLDEST AND WARMEST PERIODS AT DIFFERENT LATITUDINAL REGIONS

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Eleonora Runtunuwu

2016-10-01

Full Text Available Effect of climate change on water balance will play a key role in the biosphere system. To study the global climate change impact on water balance during 95-year period (1901-1995, long-term grid climatic data including global mean monthly temperature and precipitation at 0.5 x 0.5 degree resolution were analysed. The trend and variation of climate change, the time series of monthly air temperature and precipitation data were aggregated into annual arithmetic means for two extreme periods (1901-1920 and 1990-1995. The potential evapotranspiration (Eo was calculated using Thornthwaite method.The changes in mean annual value were obtained by subtracting the maximum period data from 1990 to 1995 (Max with the minimum period data from 1901 to 1920 (Min. The results revealed that over 95-year period, mean global air temperature increased by 0.57oC. The temperature increase varied greatly in Asia, with more than 3.0oC, especially at 45-70oN, as well over the northern part of America (60-65oN and Europe (55- 75oN. In low latitude across Asia, Africa, and South America, the variation was less than 1.5oC. In 80-85ºN region, the variation was relatively small and at higher latitudes it increasedsignificantly. Precipitation varied temporally and spatially. In the 40-45ºN and 40-45ºS regions, increasing precipitation of more than 100 mm occurred during the June-August andSeptember-November, especially in the northern hemisphere. The Eo increase of 2000 mm during 95 years occurred in the tropical northern America, middle Africa, and South-East Asia. A grid in Central Java of Indonesia showed that the Eo increase of 2500 mm during 95 years resulted in the decrease of growing period by 100 days. In coping with climate change, adjustment of cropping calendar is imperative.

Perception of secondary victimization in gender violence

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María Aranda López

2014-08-01

Full Text Available Gender violence is a complex phenomenon that does not end with the removal of the abuser, as the abused person can experience secondary victimization. This study examined this process in a sample of 38 battered women. A multicausal approach was used to assess satisfaction with health system, the police, and the judiciary. The study also assessed the role of two variables that have remained unaddressed: family support and perceived danger. The results indicate that dissatisfaction with judicial treatment and legal action plays a key role in the perception of secondary victimization. It was also found that women who perceive less risk value the judicial system more because they do not need the system to take protective measures or other measures for them. Moreover, women who receive family support are more satisfied with the police system.

Perspectives of pupils, parents, and teachers on mental health problems among Vietnamese secondary school pupils

NARCIS (Netherlands)

Nguyen, Dat Tan; Dedding, Christine; Pham, Tam Thi; Bunders-Aelen, J.G.F.

2013-01-01

Background: Secondary school can be a stressful period for adolescents, having to cope with many life changes. Very little research has been conducted on the mental health status of secondary school pupils in South East Asian countries, such as Vietnam.The study aimed to explore perceptions of

The POINT-AGAPE Survey I: The Variable Stars in M31

CERN Document Server

An Jun Hong; Hewett, P C; Baillon, Paul; Calchi-Novati, S; Carr, B J; Creze, M; Giraud-Héraud, Yannick; Gould, A; Jetzer, P; Kaplan, J; Kerins, E; Paulin-Henriksson, S; Smartt, S J; Stalin, C S; Tsapras, Y; An, Jin H.; Jetzer, Ph.

2004-01-01

The POINT-AGAPE collaboration has been monitoring M31 for three seasons with the Wide Field Camera on the Isaac Newton Telescope. In each season, data are taken for one hour per night for roughly sixty nights during the six months that M31 is visible. The two fields of view straddle the central bulge, northwards and southwards. We have calculated the locations, periods and amplitudes of 35414 variable stars in M31 as a by-product of our microlensing search. The variables are classified according to their period and amplitude of variation. They are classified into population I and II Cepheids, Miras and semi-regular long-period variables. The population I Cepheids are associated with the spiral arms, while the central concentration of the Miras and long-period variables varies noticeably, the stars with brighter (and shorter) variations being much more centrally concentrated. A crucial role in the microlensing experiment is played by the asymmetry signal. It was initially assumed that the variable stars would ...

The multi-period solution of a linear system of equations with the operator of differentiation along the main diagonal of the space of independent variables and delayed arguments

Science.gov (United States)

Sartabanov, Zhaishylyk A.

2017-09-01

A new approach to the study of periodic by all independent variables system of equations with a differentiation operator solutions along the direction of the main diagonal and with delayed arguments is proposed. The essence of the approach is to reduce the study of the multi-periodic solution of a linear inhomogeneous system to the construction of a solution of a simpler linear differential-difference system on the basis of the method of variating arbitrary constants of the complete integral of a homogeneous system. An integral representation of the unique multiperiodic solution of an inhomogeneous system is presented, expressed by a functional series of terms given by multiple repeated integrals. An estimate is given for the norm of a multi-periodic solution.

Students' Ways of Thinking about Two-Variable Functions and Rate of Change in Space

Science.gov (United States)

Weber, Eric David

2012-01-01

This dissertation describes an investigation of four students' ways of thinking about functions of two variables and rate of change of those two-variable functions. Most secondary, introductory algebra, pre-calculus, and first and second semester calculus courses do not require students to think about functions of more than one variable. Yet…

LONG-ORBITAL-PERIOD PREPOLARS CONTAINING EARLY K-TYPE DONOR STARS. BOTTLENECK ACCRETION MECHANISM IN ACTION

International Nuclear Information System (INIS)

Tovmassian, G.; González–Buitrago, D.; Zharikov, S.; Reichart, D. E.; Haislip, J. B.; Ivarsen, K. M.; LaCluyze, A. P.; Moore, J. P.; Miroshnichenko, A. S.

2016-01-01

We studied two objects identified as cataclysmic variables (CVs) with periods exceeding the natural boundary for Roche-lobe-filling zero-age main sequence (ZAMS) secondary stars. We present observational results for V1082 Sgr with a 20.82 hr orbital period, an object that shows a low luminosity state when its flux is totally dominated by a chromospherically active K star with no signs of ongoing accretion. Frequent accretion shutoffs, together with characteristics of emission lines in a high state, indicate that this binary system is probably detached, and the accretion of matter on the magnetic white dwarf takes place through stellar wind from the active donor star via coupled magnetic fields. Its observational characteristics are surprisingly similar to V479 And, a 14.5 hr binary system. They both have early K-type stars as donor stars. We argue that, similar to the shorter-period prepolars containing M dwarfs, these are detached binaries with strong magnetic components. Their magnetic fields are coupled, allowing enhanced stellar wind from the K star to be captured and channeled through the bottleneck connecting the two stars onto the white dwarf’s magnetic pole, mimicking a magnetic CV. Hence, they become interactive binaries before they reach contact. This will help to explain an unexpected lack of systems possessing white dwarfs with strong magnetic fields among detached white+red dwarf systems

LONG-ORBITAL-PERIOD PREPOLARS CONTAINING EARLY K-TYPE DONOR STARS. BOTTLENECK ACCRETION MECHANISM IN ACTION

Energy Technology Data Exchange (ETDEWEB)

Tovmassian, G.; González–Buitrago, D.; Zharikov, S. [Instituto de Astronomía, Universidad Nacional Autónoma de México, Apartado Postal 877, Ensenada, Baja California, 22800 México (Mexico); Reichart, D. E.; Haislip, J. B.; Ivarsen, K. M.; LaCluyze, A. P.; Moore, J. P. [Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Campus Box 3255, Chapel Hill, NC 27599 (United States); Miroshnichenko, A. S., E-mail: gag@astro.unam.mx, E-mail: dgonzalez@astro.unam.mx, E-mail: zhar@astro.unam.mx [Department of Physics and Astronomy, University of North Carolina at Greensboro, Greensboro, NC 27402-6170 (United States)

2016-03-01

We studied two objects identified as cataclysmic variables (CVs) with periods exceeding the natural boundary for Roche-lobe-filling zero-age main sequence (ZAMS) secondary stars. We present observational results for V1082 Sgr with a 20.82 hr orbital period, an object that shows a low luminosity state when its flux is totally dominated by a chromospherically active K star with no signs of ongoing accretion. Frequent accretion shutoffs, together with characteristics of emission lines in a high state, indicate that this binary system is probably detached, and the accretion of matter on the magnetic white dwarf takes place through stellar wind from the active donor star via coupled magnetic fields. Its observational characteristics are surprisingly similar to V479 And, a 14.5 hr binary system. They both have early K-type stars as donor stars. We argue that, similar to the shorter-period prepolars containing M dwarfs, these are detached binaries with strong magnetic components. Their magnetic fields are coupled, allowing enhanced stellar wind from the K star to be captured and channeled through the bottleneck connecting the two stars onto the white dwarf’s magnetic pole, mimicking a magnetic CV. Hence, they become interactive binaries before they reach contact. This will help to explain an unexpected lack of systems possessing white dwarfs with strong magnetic fields among detached white+red dwarf systems.

MULTI PERIOD SHOCKS ROLES ON GOVERNMENT SPENDING IN INDONESIA

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Jaka Sriyana

2011-09-01

Full Text Available This paper proposes an alternative dynamic model of government spending in Indonesia. The model is based on short term disequilibrium assumption, in which multi period of shocks variables may play an important role. This research applies a loss function approach and uses optimum shock variables as the determinant for government spending during 1970-2010. The result shows that real GDP, population, and multi period shock of government spending are statistically significant. It provides evidence of the impact of multi period shocks to the realization of government spending. It implies that government faces a serious disequilibrium in determining their spending both in short and long terms.Keywords: Fiscal, government spending, deficit budget, shockJEL classification numbers: H53, H62, C22

Understanding Farmers' Response to Climate Variability in Nigeria ...

African Journals Online (AJOL)

In this study, farmers 'response to climate variability was examined. Primary and secondary data were used. A multi-stage sampling procedure was adopted in the collection of the primary data using structured questionnaires. Four vegetation zones out of seven where farming is mainly carried out were selected for the study.

The infrared variability and nature of symbiotic stars

International Nuclear Information System (INIS)

Feast, M.W.; Catchpole, R.M.; Whitelock, P.A.; Carter, B.S.; Roberts, G.

1983-01-01

Infrared variability and spectra show that the symbiotic systems (He 2-106, He 2-38, He 2-34) contain Mira variable components. The first two also show a longer term infrared variability. It is suggested that this is due to variable dust obscuration (as in R Aqr). The phenomenon is then too frequent for the dust clouds to be confined to the orbital planes of the binary systems. Seven Miras in symbiotics have known periods which range from 370 to 580 days, suggesting a greater frequency of long-period Miras in symbiotics than in the general field. Symbiotic Miras have dust excesses with colour temperatures near 1000 K. Observations of four other symbiotic systems (Pe 2-3, He 2-87, H 2-5, AG Peg) are consistent with their containing non-variable or low amplitude M-type components. (author)

Secondary traumatic stress among emergency nurses: a cross-sectional study.

Science.gov (United States)

Duffy, Emer; Avalos, Gloria; Dowling, Maura

2015-04-01

Emergency department nurses are required to deal with emotional trauma issues on a daily basis, which may result in them experiencing symptoms of secondary traumatic stress, a consequence of stress experienced when helping or wanting to help a person traumatised or suffering. This study measured emergency department nurses' self-reported levels of secondary traumatic stress. Registered nurses (n = 117) working at three emergency departments in the Western geographical region of Ireland were invited to complete the secondary traumatic stress scale (STSS). A response rate of 90% (n = 105) was achieved. Most participants (n = 67/64%) met the criteria for secondary traumatic stress. A statistically significant finding was that the highest proportion (82%) of secondary traumatic stress existed in the staff nurse group (p = 0.042). Moreover, for those nurses reporting secondary traumatic stress, statistical significance was found for the variables 'change of career considered' (p = 0.017) and 'finds alcohol helpful in alleviating work-related stress' (p = 0.004), when compared with nurses not reporting secondary traumatic stress. The findings suggest the need to examine current crisis management interventions and to introduce new systems to support nurses in Irish emergency departments. Moreover, because different types of traumatic events in the ED require different types of interventions, the prevention and management of STS among emergency department nurses must be tackled using a variety of approaches. Copyright © 2014 Elsevier Ltd. All rights reserved.

The period of the magnetic star HD 133 029

International Nuclear Information System (INIS)

Panov, K.; Schoeneich, W.

1976-01-01

The period of 0.741285 days for the light variability of the magnetic star HD 133 029 was obtained from UBV observations. The observations of the effective magnetic field by Babcock show variations with a period of 0.7447 days. A small change of the period and a slow change of the magnitude of this magnetic star seems to be present. (author)

Variable orifice using an iris shutter

International Nuclear Information System (INIS)

Beeman, R.; Brajkovich, S.J.

1978-01-01

A variable orifice forming mechanism is described that utilizes shutter arrangement adapted to control gas flow, conductance in vacuum systems, as a heat shield for furnace windows, as a beam shutter in sputtering operations, and in any other application requiring periodic or continuously-variable control of material, gas, or fluid flow

Music Listening--Romantic Period (1815-1914), Music: 5635.794.

Science.gov (United States)

Pearl, Jesse; Carter, Raymond

This secondary level Quinmester course is designed to teach the principal types of vocal, instrumental, and operatic compositions of the Romantic period through listening to the styles of different composers and acquiring recognition of their works. The course is intended for students who have participated in fine or performing arts and for pupils…

Low-Frequency Temporal Variability in Mira and Semiregular Variables

Science.gov (United States)

Templeton, Matthew R.; Karovska, M.; Waagen, E. O.

2012-01-01

We investigate low-frequency variability in a large sample of Mira and semiregular variables with long-term visual light curves from the AAVSO International Database. Our aim is to determine whether we can detect and measure long-timescale variable phenomena in these stars, for example photometric variations that might be associated with supergranular convection. We analyzed the long-term light curves of 522 variable stars of the Mira and SRa, b, c, and d classes. We calculated their low-frequency time-series spectra to characterize rednoise with the power density spectrum index, and then correlate this index with other observable characteristics such as spectral type and primary pulsation period. In our initial analysis of the sample, we see that the semiregular variables have a much broader range of spectral index than the Mira types, with the SRb subtype having the broadest range. Among Mira variables we see that the M- and S-type Miras have similarly wide ranges of index, while the C-types have the narrowest with generally shallower slopes. There is also a trend of steeper slope with larger amplitude, but at a given amplitude, a wide range of slopes are seen. The ultimate goal of the project is to identify stars with strong intrinsic red noise components as possible targets for resolved surface imaging with interferometry.

Amputation Surgery in a Secondary Healthcare Facility in Nigeria ...

African Journals Online (AJOL)

... our experience in amputation surgery over a ten – year period in a secondary healthcare facility in sub- Saharan Africa. A retrospective study of 117 patients that underwent amputation in the facility between January 1998 and December 2007. Trauma remains the commonest indication for amputation in our environment.

[A study of relationship between occupational stress and diseases in secondary school teachers].

Science.gov (United States)

Zhang, Yang; Zhu, Tao; Tang, Liu; Li, Jian; Lan, Yajia

2015-10-01

To analyze the relationship between occupational stress and diseases in secondary school teachers in a city of Sichuan Province, and to provide a basis for the evaluation of the long-term effects of occupational stress in teachers. With secondary school teachers as the target population, the stratified cluster sampling was adopted to conduct three studies among 780, 119, and 689 secondary school teachers in a city of Sichuan Province in 1999, 2005, and 2009, respectively. The Occupational Stress Inventory-Revised Edition (OSI-R) and working ability index (WAI) were used to investigate occupational stress and diseases in secondary school teachers. The variation of occupational stress in secondary school teachers was compared between different periods and the relationship between the intensity of stress and diseases was evaluated, on the basis of which the variation of the relationship over time was analyzed. There were significant differences in occupational stress in secondary school teachers between different periods (Pstress and psychological stress were significantly higher in 2009 than in 1999 (Poccupational stress in 2009 changed with cardiovascular, respiratory, and mental diseases. The incidence of abnormal psychological stress was a risk factor for all chronic, respiratory, and mental diseases (OR: 1.88, 2.25, and 5.91). The time dependence of odds ratio was only found in the risk of respiratory diseases: occupational stress resulted in a significant increase in the risk of respiratory diseases over time (Pstress was a risk factor for mental diseases (OR=2.31). The intensity of occupational stress in secondary school teachers changes over time. Occupational stress elevates the risks of certain diseases and has a time-dependent effect on the risk of respiratory diseases. Occupational stress in secondary school teachers needs more attention and effective prevention.

Current and desired competency levels of secondary agricultural teachers in Pennsylvania

Science.gov (United States)

Elbert, Chanda Dehron

The purpose of this study was to identify the competencies needed by secondary agricultural teachers in the Commonwealth of Pennsylvania. Specifically, this study identified competencies needed to help make teachers more effective while working with special needs students. The objectives of the study were to: (1) determine, verify, and evaluate competencies needed by secondary teachers of agriculture to work with handicapped students enrolled in agricultural and vocational education programs; (2) determine, verify, and evaluate competencies needed by secondary teachers of agriculture to work with economically disadvantaged students enrolled in agricultural and vocational education programs; (3) determine, verify, and evaluate competencies needed by secondary teachers of agriculture to work with academically challenged students enrolled in agricultural and vocational programs; and (4) evaluate the self-perceived competency levels of secondary agricultural education teachers and their desired competency levels. A 50% simple random sample of secondary agricultural teachers from the Directory for Agricultural Education in Pennsylvania, 1999--2000 was used. The design for the study was a descriptive study. The data collection instrument used was divided into five different areas: personal characteristics, professional role and development, instructional role, knowledge statements, and student leadership and organization. Subjects were asked to rate their present and desired levels of competency in the categories using a Likert-type scale. The competency scale was as follows: 1 = not competent; 2 = slightly competent, 3 = competent; 4 = very competent; 5 = extremely competent. There were 153 questionnaires mailed to the secondary agricultural education teachers. A total of 96 teachers responded to the questionnaire. Frequencies and distributions were used to describe demographic variables. T-test and analysis of variance were used to determine relationships between

Amino acid code of protein secondary structure.

Science.gov (United States)

Shestopalov, B V

2003-01-01

The calculation of protein three-dimensional structure from the amino acid sequence is a fundamental problem to be solved. This paper presents principles of the code theory of protein secondary structure, and their consequence--the amino acid code of protein secondary structure. The doublet code model of protein secondary structure, developed earlier by the author (Shestopalov, 1990), is part of this theory. The theory basis are: 1) the name secondary structure is assigned to the conformation, stabilized only by the nearest (intraresidual) and middle-range (at a distance no more than that between residues i and i + 5) interactions; 2) the secondary structure consists of regular (alpha-helical and beta-structural) and irregular (coil) segments; 3) the alpha-helices, beta-strands and coil segments are encoded, respectively, by residue pairs (i, i + 4), (i, i + 2), (i, i = 1), according to the numbers of residues per period, 3.6, 2, 1; 4) all such pairs in the amino acid sequence are codons for elementary structural elements, or structurons; 5) the codons are divided into 21 types depending on their strength, i.e. their encoding capability; 6) overlappings of structurons of one and the same structure generate the longer segments of this structure; 7) overlapping of structurons of different structures is forbidden, and therefore selection of codons is required, the codon selection is hierarchic; 8) the code theory of protein secondary structure generates six variants of the amino acid code of protein secondary structure. There are two possible kinds of model construction based on the theory: the physical one using physical properties of amino acid residues, and the statistical one using results of statistical analysis of a great body of structural data. Some evident consequences of the theory are: a) the theory can be used for calculating the secondary structure from the amino acid sequence as a partial solution of the problem of calculation of protein three

[Secondary hypertension].

Science.gov (United States)

Yoshida, Yuichi; Shibata, Hirotaka

2015-11-01

Hypertension is a common disease and a crucial predisposing factor of cardiovascular diseases. Approximately 10% of hypertensive patients are secondary hypertension, a pathogenetic factor of which can be identified. Secondary hypertension consists of endocrine, renal, and other diseases. Primary aldosteronism, Cushing's syndrome, pheochromocytoma, hyperthyroidism, and hypothyroidism result in endocrine hypertension. Renal parenchymal hypertension and renovascular hypertension result in renal hypertension. Other diseases such as obstructive sleep apnea syndrome are also very prevalent in secondary hypertension. It is very crucial to find and treat secondary hypertension at earlier stages since most secondary hypertension is curable or can be dramatically improved by specific treatment. One should keep in mind that screening of secondary hypertension should be done at least once in a daily clinical practice.

Climatology and forest decay - stresses caused by dry periods

International Nuclear Information System (INIS)

Havlik, D.

1991-01-01

In the discussion of forest decline in the Eighties, stresses due to dry weather is often named as a secondary cause. The concept of 'climatological dry periods' is introduced in this article and applied to records for the Basel and Aachen regions. The time distribution of dry periods of different length and different water deficiency (40 mm, 60 mm, 100 mm) is analyzed. In the case of the Basel data, the dry periods are related to the 'forest damage caused by draught' recorded for the Basel region since 1930. The results support the theory that increasingly larger and more frequent dry periods with water shortage have contributed significantly to forest damage in the last 15 years. Apart from the 'dry stress' itself, also the enhanced production of photooxidants is a damaging mechanism. (orig.) [de

Secondary and tertiary hyperparathyroidism in chronic kidney disease

Directory of Open Access Journals (Sweden)

Lilit V. Egshatyan

2017-12-01

Full Text Available In the treatment of secondary hyperparathyroidism of end-stage chronic kidney disease, vitamin D receptor activation and allosteric modulators of the calcium-sensing receptor – inhibit glandular hyperplasia, reduce parathyroid hormone levels, impact on bone turnover and mineral density. But the use of calcimimetic and vitamin D analogs or mimetics did not reduce the need for parathyroidectomy for refractory hyperparathyroidism. The enlarged parathyroid gland and gland nodular transformation became refractory to medical therapy and patient need for parathyroidectomy. Tertiary hyperparathyroidism is a state of excessive secretion of parathyroid hormone after a long period of secondary hyperparathyroidism and renal transplantation. In this article, we present the case of a Caucasian male with chronic kidney disease (end-stage on chronic hemodialysis and after kidney transplantation and different forms of hyperparathyroidism (secondary and tertiary. Our case study shows that only a multi-interventional strategy is likely to be more effective treatment in cases of severe and refractory to medical therapy hyperparathyroidism.

Variable stars in the classroom

Energy Technology Data Exchange (ETDEWEB)

Sanchez-Bajo, F [Departamento de Electronica e IngenierIa Electromecanica, Escuela de IngenierIas Industriales, Universidad de Extremadura, Avda de Elvas s/n, 06071 Badajoz (Spain); Vaquero, J M [Departamento de Fisica, Escuela Politecnica, Universidad de Extremadura, Avda de la Universidad s/n, 10071 Caceres (Spain)

2006-05-01

Variable stars offer interesting possibilities from the point of view of educational applications, from the experimental collection of data to analysis to obtain physical information. In this paper, brightness measurements of two periodic variable stars easily accessible with small telescopes are presented and analysed. This practical experiment is highly appropriate for educational use in undergraduate physics and astrophysics laboratories and allows students to approximate scientific research.

Variable stars in the classroom

International Nuclear Information System (INIS)

Sanchez-Bajo, F; Vaquero, J M

2006-01-01

Variable stars offer interesting possibilities from the point of view of educational applications, from the experimental collection of data to analysis to obtain physical information. In this paper, brightness measurements of two periodic variable stars easily accessible with small telescopes are presented and analysed. This practical experiment is highly appropriate for educational use in undergraduate physics and astrophysics laboratories and allows students to approximate scientific research

The Strategy of New Product Introduction in Durable Goods with Secondary Market: Application of the Optimization Method to Supply Chain Problem

Directory of Open Access Journals (Sweden)

Pei Zhao

2014-01-01

Full Text Available The aim of this paper is to address how the secondary market affects the strategy of the manufacturer’s new product introduction by using the optimization method. To do so, we develop a two-period model in which a monopolistic manufacturer sells its new durable products directly to end consumers in both periods, while an entrant operates a reverse channel selling used products in the secondary market. We assume that the manufacturer launches a higher quality product in the second period for the technological innovation. We find that the secondary market can actually increase the manufacturer’s profitability and drives the new product introduction in the second period. We also derive the effect of the durability and the degree of quality improvement on the pricing of supply chain partners.

STELLAR PULSATIONS AND PERIOD CHANGES IN THE SX PHOENICIS STAR XX CYGNI

International Nuclear Information System (INIS)

Yang, X. H.; Fu, J. N.; Zha, Q.

2012-01-01

Time-series photometric observations were made for the SX Phoenicis star XX Cyg between 2007 and 2011 at the Xinglong Station of National Astronomical Observatories of China. With the light curves derived from the new observations, we do not detect any secondary maximum in the descending portion of the light curves of XX Cyg, as reported in some previous work. Frequency analysis of the light curves confirms a fundamental frequency f 0 = 7.4148 cycles day –1 and up to 19 harmonics, 11 of which are newly detected. However, no secondary mode of pulsation is detected from the light curves. The O–C diagram, produced from 46 newly determined times of maximum light combined with those derived from the literature, reveals a continuous period increase with the rate of (1/P)(dP/dt) = 1.19(13) × 10 –8 yr -1 . Theoretical rates of period change due to the stellar evolution were calculated with a modeling code. The result shows that the observed rate of period change is fully consistent with period change caused by evolutionary behavior predicted by standard theoretical models.

History of a secondary side inspection tooling development

International Nuclear Information System (INIS)

Harris, W.

2012-01-01

This presentation provides a brief history (1980 to present day) of steam generator secondary side tooling requirements, tooling development, tooling available today and how and where this tooling has been implemented for steam generator secondary side inspections. History of Tooling Development discussion covers the relatively short time period from when the SGSS tooling was required and why as well the associated challenges with development through present day; Available Tooling discussion covers the actual tooling available today, locations in the steam generator where the tooling is used and how the tooling works; Implementation discussion covers where in the world this tooling has been deployed as well the benefits the tooling has provided. (author)

Global variability of cloud condensation nuclei concentrations

Science.gov (United States)

Makkonen, Risto; Krüger, Olaf

2017-04-01

Atmospheric aerosols can influence cloud optical and dynamical processes by acting as cloud condensation nuclei (CCN). Globally, these indirect aerosol effects are significant to the radiative budget as well as a source of high uncertainty in anthropogenic radiative forcing. While historically many global climate models have fixed CCN concentrations to a certain level, most state-of-the-art models calculate aerosol-cloud interactions with sophisticated methodologies based on interactively simulated aerosol size distributions. However, due to scarcity of atmospheric observations simulated global CCN concentrations remain poorly constrained. Here we assess global CCN variability with a climate model, and attribute potential trends during 2000-2010 to changes in emissions and meteorological fields. Here we have used ECHAM5.5-HAM2 with model M7 microphysical aerosol model. The model has been upgraded with a secondary organic aerosol (SOA) scheme including ELVOCs. Dust and sea salt emissions are calculated online, based on wind speed and hydrology. Each experiment is 11 years, analysed after a 6-month spin-up period. The MODIS CCN product (Terra platform) is used to evaluate model performance throughout 2000-2010. While optical remote observation of CCN column includes several deficiencies, the products serves as a proxy for changes during the simulation period. In our analysis we utilize the observed and simulated vertical column integrated CCN concentration, and limit our analysis only over marine regions. Simulated annual CCN column densities reach 2ṡ108 cm-2 near strong source regions in central Africa, Arabian Sea, Bay of Bengal and China sea. The spatial concentration gradient in CCN(0.2%) is steep, and column densities drop to coasts. While the spatial distribution of CCN at 0.2% supersaturation is closer to that of MODIS proxy, as opposed to 1.0% supersaturation, the overall column integrated CCN are too low. Still, we can compare the relative response of CCN

Causal Variables and Academic Performance of Students in Cross ...

African Journals Online (AJOL)

This study investigated the causal variables (Child, Family, School, Society and Government) and academic performance of secondary school students in Cross River State: A basis for counselling and programme planning. The study adopted the descriptive survey method. It made use of two research questions and ...

Psychosocial Variables as Predictors of School Adjustment of Gifted Students with Learning Disabilities in Nigeria

Science.gov (United States)

Fakolade, O. A.; Oyedokun, S. O.

2015-01-01

The paper considered several psychosocial variables as predictors of school adjustment of 40 gifted students with learning disabilities in Junior Secondary School in Ikenne Local Government Council Area of Ogun State, Nigeria. Purposeful random sampling was employed to select four schools from 13 junior secondary schools in the area, six…

143 GHz BRIGHTNESS MEASUREMENTS OF URANUS, NEPTUNE, AND OTHER SECONDARY CALIBRATORS WITH BOLOCAM BETWEEN 2003 AND 2010

International Nuclear Information System (INIS)

Sayers, J.; Czakon, N. G.; Golwala, S. R.

2012-01-01

Bolocam began collecting science data in 2003 as the long-wavelength imaging camera at the Caltech Submillimeter Observatory. The planets, along with a handful of secondary calibrators, have been used to determine the flux calibration for all of the data collected with Bolocam. Uranus and Neptune stand out as the only two planets that are bright enough to be seen with high signal-to-noise in short integrations without saturating the standard Bolocam readout electronics. By analyzing all of the 143 GHz observations made with Bolocam between 2003 and 2010, we find that the brightness ratio of Uranus to Neptune is 1.027 ± 0.006, with no evidence for any variations over that period. Including previously published results at ≅ 150 GHz, we find a brightness ratio of 1.029 ± 0.006 with no evidence for time variability over the period 1983-2010. Additionally, we find no evidence for time variability in the brightness ratio of either Uranus or Neptune to the ultracompact H II region G34.3 or the protostellar source NGC 2071IR. Using recently published Wilkinson Microwave Anisotropy Probe results we constrain the absolute 143 GHz brightness of both Uranus and Neptune to ≅ 3%. Finally, we present ≅ 3% absolute 143 GHz peak flux density values for the ultracompact H II regions G34.3 and K3-50A and the protostellar source NGC 2071IR.

Adverse Effects with Ambulatory Intravenous Immunoglobulin Administration in Adult Patients with Common Variable Immunodeficiency

Directory of Open Access Journals (Sweden)

Karen Alicia Rodríguez-Mireles

2014-06-01

Full Text Available Background: Common variable immunode ciency (CVID is the most frequent symptomatic primary immunodeficiency, affecting 1:25,000- 75,000 people. It is characterized by the absence or decrease antibody production. Treatment for CVID consists on human immunoglobulin administration, and the intravenous route is the most common route for administration, at 400-800 mg/kg of weight every 3-4 weeks. Adverse effects associated with intravenous immunoglobulin (IVIg use occur in 25% of all infusions, with severe adverse reactions presenting in less than 1% of all patients. Acute renal failure can occur as a severe adverse reaction, which presents 1-10 days after starting IVIg treatment. In our center we implemented an ambulatory scheme for IVIg administration, which allows its administration in an average of 3 hours, without severe adverse effects. Objectives: To describe adverse effects and to evaluate the frequency of renal failure secondary to ambulatory IVIg administration in patients with common variable immunode ciency. Material and method: A descriptive and prospective study was done including adult patients con de nitive diagnosis of common variable immunodeficiency, receiving IVIg at replacement dose every 3 weeks. All patients were evaluated with clinical exploration, somatometry, serum creatinine, albumin and urea determination, 24 hours creatinine clearance, glomerular ltration rate with CKD-EPI, and immediate renal function associated with accumulated IVIg. Results were analyzed with descriptive statistics. Results: We determined adverse effects in 25 patients with common variable immunode ciency (15 women and 10 men, average age 36.7 years, during a 10 months period (January-September 2013. During this period 284 IVIg infusions were administered using our scheme, frequency of adverse effects were 12.9%, with 5.2% of early adverse effects and 7.7% late adverse effects, all being mild to moderate, in some cases required analgesic and

Seasonal variations in secondary production of the Mandovi-Zuari estuarine system of Goa

Digital Repository Service at National Institute of Oceanography (India)

Selvakumar, R.A.; Nair, V.R.; Madhupratap, M.

. In general, the saline period was more productive (12.9 mg dry wt/m3/day) compared to the low saline period (11 mg dry wt/m3/day). The average secondary production in the estuarine system was 21.4 mg dry wt/m3/day or 1078 tonnes carbon/yr. The coefficient...

Polysheroidal periodic functions

International Nuclear Information System (INIS)

Truskova, N.F.

1985-01-01

Separation of variables in the Helmholtz N-dimensional (N≥4) equation in polyspheroidal coordinate systems leads to the necessity of solving equations going over into equations for polyspheroidal periodic functions used for solving the two-centre problem in quantum mechanics, the three-body problem with Coulomb interaction, etc. For these functions the expansions are derived in terms of the Jacobi polynomials and Bessel functions. Their basic properties, asymptotics are considered. The algorithm of their computer calculations is developed. The results of numerical calculations are given

Characteristics and generation of secondary jets and secondary gigantic jets

Science.gov (United States)

Lee, Li-Jou; Huang, Sung-Ming; Chou, Jung-Kung; Kuo, Cheng-Ling; Chen, Alfred B.; Su, Han-Tzong; Hsu, Rue-Rou; Frey, Harald U.; Takahashi, Yukihiro; Lee, Lou-Chuang

2012-06-01

Secondary transient luminous events (TLEs) recorded by the ISUAL-FORMOSAT2 mission can either be secondary jets or secondary gigantic jets (GJs), depending on their terminal altitudes. The secondary jets emerge from the cloud top beneath the preceding sprites and extend upward to the base of the sprites at ˜50 km. The secondary jets likely are negative electric discharges with vertically straight luminous columns, morphologically resembling the trailing jet of the type-I GJs. The number of luminous columns in a secondary jet seems to be affected by the size of the effective capacitor plate formed near the base of the preceding sprites and the charge distribution left behind by the sprite-inducing positive cloud-to-ground discharges. The secondary GJs originate from the cloud top under the shielding area of the preceding sprites, and develop upward to reach the lower ionosphere at ˜90 km. The observed morphology of the secondary GJs can either be the curvy shifted secondary GJs extending outside the region occupied by the preceding sprites or the straight pop-through secondary GJs developing through the center of the preceding circular sprites. A key factor in determining the terminal height of the secondary TLEs appears to be the local ionosphere boundary height that established by the preceding sprites. The abundance and the distribution of the negative charge in the thundercloud following the sprite-inducing positive cloud-to-ground discharges may play important role in the generation of the secondary TLEs.

The Taiwanese-American occultation survey project stellar variability. III. Detection of 58 new variable stars

Energy Technology Data Exchange (ETDEWEB)

Ishioka, R.; Wang, S.-Y.; Zhang, Z.-W.; Lehner, M. J.; Cook, K. H.; King, S.-K.; Lee, T.; Marshall, S. L.; Schwamb, M. E.; Wang, J.-H.; Wen, C.-Y. [Institute of Astronomy and Astrophysics, Academia Sinica, 11F of Astronomy-Mathematics Building, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan (China); Alcock, C.; Protopapas, P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Axelrod, T. [Steward Observatory, 933 North Cherry Avenue, Room N204, Tucson, AZ 85721 (United States); Bianco, F. B. [Center for Cosmology and Particle Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Byun, Y.-I. [Department of Astronomy and University Observatory, Yonsei University, 134 Shinchon, Seoul 120-749 (Korea, Republic of); Chen, W. P.; Ngeow, C.-C. [Institute of Astronomy, National Central University, No. 300, Jhongda Road, Jhongli City, Taoyuan County 320, Taiwan (China); Kim, D.-W. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Rice, J. A., E-mail: ishioka@asiaa.sinica.edu.tw [Department of Statistics, University of California Berkeley, 367 Evans Hall, Berkeley, CA 94720 (United States)

2014-04-01

The Taiwanese-American Occultation Survey project is designed for the detection of stellar occultations by small-size Kuiper Belt Objects, and it has monitored selected fields along the ecliptic plane by using four telescopes with a 3 deg{sup 2} field of view on the sky since 2005. We have analyzed data accumulated during 2005-2012 to detect variable stars. Sixteen fields with observations of more than 100 epochs were examined. We recovered 85 variables among a total of 158 known variable stars in these 16 fields. Most of the unrecovered variables are located in the fields observed less frequently. We also detected 58 variable stars which are not listed in the International Variable Star Index of the American Association of Variable Star Observers. These variable stars are classified as 3 RR Lyrae, 4 Cepheid, 1 δ Scuti, 5 Mira, 15 semi-regular, and 27 eclipsing binaries based on the periodicity and the profile of the light curves.

Distribution, variability, and predictors of urinary bisphenol A levels in 50 North Carolina adults over a six-week monitoring period.

Science.gov (United States)

Morgan, Marsha K; Nash, Maliha; Barr, Dana Boyd; Starr, James M; Scott Clifton, M; Sobus, Jon R

2018-03-01

Bisphenol A (BPA) is commonly manufactured to make polycarbonate plastics and epoxy resins for use in consumer products and packaged goods. BPA has been found in several different types of environmental media (e.g., food, dust, and air). Many cross-sectional studies have frequently detected BPA concentrations in adult urine samples. However, limited data are available on the temporal variability and important predictors of urinary BPA concentrations in adults. In this work, the major objectives were to: 1) quantify BPA levels in duplicate-diet solid food, drinking water, hard floor surface wipe, and urine samples (first-morning void [FMV], bedtime, and 24-h) collected from adults over a six-week monitoring period; 2) determine the temporal variability of urinary BPA levels using concentration, specific gravity (SG) adjusted, creatinine (CR) adjusted, and excretion rate values, and; 3) examine associations between available study factors and urinary BPA concentrations. In 2009-2011, a convenience sample of 50 adults was recruited from residential settings in North Carolina. The participants completed diaries and collected samples during weeks 1, 2, and/or 6 of a six-week monitoring period. BPA was detected in 38%, 4%, and 99% of the solid food (n=775), drinking water (n=50), and surface wipe samples (n=138), respectively. Total BPA (free plus conjugated) was detected in 98% of the 2477 urine samples. Median urinary BPA levels were 2.07ng/mL, 2.20ng/mL-SG, 2.29ng/mg, and 2.31ng/min for concentration, SG-adjusted, CR-adjusted, and excretion rate values, respectively. The intraclass correlation coefficient (ICC) estimates for BPA showed poor reproducibility (≤0.35) for all urine sample types and methods over a day, week, and six weeks. CR-adjusted bedtime voids collected over six-weeks required the fewest, realistic number of samples (n=11) to obtain a reliable biomarker estimate (ICC=0.80). Results of linear mixed-effects models showed that sex, race, season, and CR

Optical photometric variable stars towards the Galactic H II region NGC 2282

Science.gov (United States)

Dutta, Somnath; Mondal, Soumen; Joshi, Santosh; Jose, Jessy; Das, Ramkrishna; Ghosh, Supriyo

2018-05-01

We report here CCD I-band time series photometry of a young (2-5 Myr) cluster NGC 2282, in order to identify and understand the variability of pre-main-sequence (PMS) stars. The I-band photometry, down to ˜20.5 mag, enables us to probe the variability towards the lower mass end (˜0.1 M⊙) of PMS stars. From the light curves of 1627 stars, we identified 62 new photometric variable candidates. Their association with the region was established from H α emission and infrared (IR) excess. Among 62 variables, 30 young variables exhibit H α emission, near-IR (NIR)/mid-IR (MIR) excess or both and are candidate members of the cluster. Out of 62 variables, 41 are periodic variables, with a rotation rate ranging from 0.2-7 d. The period distribution exhibits a median period at ˜1 d, as in many young clusters (e.g. NGC 2264, ONC, etc.), but it follows a unimodal distribution, unlike others that have bimodality, with slow rotators peaking at ˜6-8 d. To investigate the rotation-disc and variability-disc connection, we derived the NIR excess from Δ(I - K) and the MIR excess from Spitzer [3.6]-[4.5] μm data. No conclusive evidence of slow rotation with the presence of discs around stars and fast rotation for discless stars is obtained from our periodic variables. A clear increasing trend of the variability amplitude with IR excess is found for all variables.

Perspectives of pupils, parents, and teachers on mental health problems among Vietnamese secondary school pupils

OpenAIRE

Nguyen, Dat Tan; Dedding, Christine; Pham, Tam Thi; Bunders-Aelen, J.G.F.

2013-01-01

Background: Secondary school can be a stressful period for adolescents, having to cope with many life changes. Very little research has been conducted on the mental health status of secondary school pupils in South East Asian countries, such as Vietnam.The study aimed to explore perceptions of mental health status, risk factors for mental health problems and strategies to improve mental health among Vietnamese secondary school students. Methods. A qualitative design was used to address the ma...

Incentivizing Advanced Mathematics Study at Upper Secondary Level: The Case of Bonus Points in Ireland

Science.gov (United States)

Treacy, Páraic Thomas

2018-01-01

Secondary level mathematics education in Ireland has recently experienced a period of significant change with the introduction of new curricula and the addition of an incentive to study upper secondary mathematics at the most advanced level (Higher Level). This incentive, typically referred to as 'bonus points', appears to have aided a significant…

Primary versus secondary hypertension in children followed up at an outpatient tertiary unit.

Science.gov (United States)

Gomes, Romina S; Quirino, Isabel G; Pereira, Regina M; Vitor, Breno M; Leite, Alysson F; Oliveira, Eduardo A; Simões e Silva, Ana Cristina

2011-03-01

Childhood hypertension has classically been recognized as a secondary disease. However, primary hypertension also occurs in children. The aim of this study was to compare clinical features of pediatric patients with elevated blood pressure, which were referred to an outpatient tertiary unit, and to detect variables associated with the identification of primary hypertension. The records of 220 patients with hypertension followed between 1996 and 2006 were analyzed. The variable of interest was primary hypertension. Logistic regression analysis was applied to identify clinical variables that were independently associated with primary hypertension. Of 220 patients, 33 (15%) had primary hypertension, and 187 (85%) exhibited secondary hypertension. No statistically significant differences were detected in gender, race, age at diagnosis, and systolic/diastolic blood pressure levels between both groups. After adjustment, four variables at baseline remained independently associated with primary hypertension: absence of signs/symptoms (OR 18.87, 95% CI 6.32-56.29), normal serum creatinine (OR 0.02, 95% CI 0.00-0.27), family history of hypertension (OR 3.03, 95% CI 1.04-8.79), and elevated body weight (OR 1.06, 95% CI 1.02-1.10). The absence of signs/symptoms, normal serum creatinine, family history of hypertension, and overweight/obesity at admission are clues to diagnose primary hypertension in childhood.

Hyponatremic hypertensive syndrome secondary to renal ischemia – Case report

Directory of Open Access Journals (Sweden)

Joana Cunha Oliveira

2018-01-01

Full Text Available Hyponatremic hypertensive syndrome (HHS is characterized by hypertensive crisis, and hyponatremia secondary to unilateral renal damage with glomerular and tubular dysfunction. Elevated plasma levels of renin in most cases suggest that the stimulation of renin release from the ischemic kidney plays an important pathophysiologic role. Activation of the renin-angiotensin system results in hypertension and causes secondary hyperfiltration, pressure diuresis and sodium loss from contralateral non-damaged kidney. An elevated renin level is a pathognomonic finding in HHS. Potassium deficiency from hyperaldosteronism may further stimulate renin secretion and intensify this vicious circle.We report a female term newborn, who presented with hypertensive crisis on the seventh day after traumatic birth. The first three days of life were uneventful. Initial treatment with captopril resulted in severe hypotension and hemodynamic instability. Lab work revealed hyponatremia, hypokalemia, and elevated peripheral renin activity and aldosterone levels. Complementary sonography and magnetic resonance confirmed right adrenal gland hematoma and several ischemic areas in the upper pole of the right kidney. The diagnosis of HHS secondary to renal ischemia was evoked.HHS is a rare condition in the neonatal period, though still under-recognized. In the neonatal and early infancy period, renovascular disease is the most common cause of secondary hypertension. In this case, there was no sign of vascular disease, the renin-angiotensin system was activated secondary to direct renal ischemia and infarction. The intense renin stimulation and pressure through the contralateral normal kidney results in high pressure natriuresis facilitating a severe volume-depleted state. Although the use of renin-angiotensin system inhibitors is the treatment of choice, it is imperative to re-establish hydration and renal perfusion before starting this antihypertensive medication. We aimed to

Transient Diagnosis and Prognosis for Secondary System in Nuclear Power Plants

Directory of Open Access Journals (Sweden)

Sangjun Park

2016-10-01

Full Text Available This paper introduces the development of a transient monitoring system to detect the early stage of a transient, to identify the type of the transient scenario, and to inform an operator with the remaining time to turbine trip when there is no operator's relevant control. This study focused on the transients originating from a secondary system in nuclear power plants (NPPs, because the secondary system was recognized to be a more dominant factor to make unplanned turbine-generator trips which can ultimately result in reactor trips. In order to make the proposed methodology practical forward, all the transient scenarios registered in a simulator of a 1,000 MWe pressurized water reactor were archived in the transient pattern database. The transient patterns show plant behavior until turbine-generator trip when there is no operator's intervention. Meanwhile, the operating data periodically captured from a plant computer is compared with an individual transient pattern in the database and a highly matched section among the transient patterns enables isolation of the type of transient and prediction of the expected remaining time to trip. The transient pattern database consists of hundreds of variables, so it is difficult to speedily compare patterns and to draw a conclusion in a timely manner. The transient pattern database and the operating data are, therefore, converted into a smaller dimension using the principal component analysis (PCA. This paper describes the process of constructing the transient pattern database, dealing with principal components, and optimizing similarity measures.

Extended Delivery Time Analysis for Cognitive Packet Transmission With Application to Secondary Queuing Analysis

KAUST Repository

Usman, Muneer

2015-05-21

Cognitive radio transceiver can opportunistically access the underutilized spectrum resource of primary systems for new wireless services. With interweave implementation, the secondary transmission may be interrupted by the primary user\\'s transmission. To facilitate the delay analysis of such secondary transmission for fixed-size secondary packets, we study the resulting extended delivery time that includes both transmission time and waiting time. In particular, we derive the exact distribution functions of extended delivery time of secondary transmission for both continuous sensing and periodic sensing cases. Selected numerical and simulation results are presented for illustrating the mathematical formulation. Finally, we consider an M/G/1 queueing set-up at the secondary transmitter and formulate the closed-form expressions for the expected delay with Poisson traffic. The analytical results will greatly facilitate the design of the secondary system for particular target application. © 2015 IEEE.

Investigating Burnout among Elementary and Secondary School Music Educators: A Replication

Science.gov (United States)

Bernhard, H. Christian II

2016-01-01

The primary purpose of the study was to compare perceived levels of burnout among music educators by grade level taught, state teaching certification status, and music specialization. The secondary purpose was to examine relationships among perceived burnout, and academic as well as personal variables. Participants for the study were 258…

Effect of Integrated Feedback on Classroom Climate of Secondary School Teachers

Science.gov (United States)

Patel, Nilesh Kumar

2018-01-01

This study aimed at finding out the effect of Integrated feedback on Classroom climate of secondary school teachers. This research is experimental in nature. Non-equivalent control group design suggested by Stanley and Campbell (1963) was used for the experiment. Integrated feedback was treatment and independent variable, Classroom climate was…

Variability in carbon exchange of European croplands

DEFF Research Database (Denmark)

Eddy J, Moors; Jacobs, Cor; Jans, Wilma

2010-01-01

The estimated net ecosystem exchange (NEE) of CO2 based on measurements at 17 flux sites in Europe for 45 cropping periods showed an average loss of -38 gC m-2 per cropping period. The cropping period is defined as the period after sowing or planting until harvest. The variability taken as the st......The estimated net ecosystem exchange (NEE) of CO2 based on measurements at 17 flux sites in Europe for 45 cropping periods showed an average loss of -38 gC m-2 per cropping period. The cropping period is defined as the period after sowing or planting until harvest. The variability taken...... as the standard deviation of these cropping periods was 251 gC m-2. These numbers do not include lateral inputs such as the carbon content of applied manure, nor the carbon exchange out of the cropping period. Both are expected to have a major effect on the C budget of high energy summer crops such as maize. NEE...... and gross primary production (GPP) can be estimated by crop net primary production based on inventories of biomass at these sites, independent of species and regions. NEE can also be estimated by the product of photosynthetic capacity and the number of days with the average air temperature >5 °C. Yield...

Influence of chemoreflexes on respiratory variability in healthy subjects

NARCIS (Netherlands)

van den Aardweg, Joost G.; Karemaker, John M.

2002-01-01

The background of this study was the hypothesis that respiratory variability is influenced by chemoreflex regulation, In search for periodicities in the variability due to instability of the respiratory control system, spectral analysis was applied to breath-to-breath variables in 19 healthy

Factors affecting the uptake of new medicines in secondary care - a literature review.

Science.gov (United States)

Chauhan, D; Mason, A

2008-08-01

The rate of uptake of new medicines in the UK is slower than in many other OECD countries. The majority of new medicines are introduced initially in secondary care and prescribed by specialists. However, the reasons for relatively low precribing levels are poorly understood. This review explores the determinants of uptake of new medicines in secondary care. Nine electronic databases were searched covering the period 1992-2006. Once the searches had been run, records were downloaded and those which evaluated uptake of new medicines in secondary care were identified. UK studies were of primary interest, although research conducted in other countries was also reviewed if relevant. With the exception of 'think pieces', eligibility was not limited by study design. Studies published in languages other than English were excluded from the review. Determinants of uptake in secondary care were classified using Bonair and Persson's typology for determinants of the diffusion of innovation. Almost 1400 records were screened for eligibility, and 29 studies were included in the review. Prescribing of new medicines in secondary care was found to be subject to a number of interacting influences. The support structures which exist within secondary care facilitate access to other colleagues and shape prescribing practices. Clinical trial investigators and physicians who sit on decision-making bodies such as Drug and Therapeutic Committees (DTCs) appear to have a special influence due to their proximity to their research and understanding of evidence base. Pharmaceutical representatives may also influence prescribing decisions through funding of meetings and academic detailing, but clinicians are wary of potential bias. Little evidence on the influence of patients upon prescribing decisions was identified. The impact of clinical guidelines has been variable. Some guidelines have significantly increased the uptake of new medicines, but others have had little discernible impact despite

ULTRA-LOW AMPLITUDE VARIABLES IN THE LARGE MAGELLANIC CLOUD-CLASSICAL CEPHEIDS, POP. II CEPHEIDS, RV TAU STARS, AND BINARY VARIABLES

International Nuclear Information System (INIS)

Robert Buchler, J.; Wood, Peter R.; Soszynski, Igor

2009-01-01

A search for variable stars with ultra-low amplitudes (ULAs), in the millimagnitude range, has been made in the combined MACHO and OGLE databases in the broad vicinity of the Cepheid instability strip in the HR diagram. A total of 25 singly periodic and 4 multiply periodic ULA objects have been uncovered. Our analysis does not allow us to distinguish between pulsational and ellipsoidal (binary) variabilities, nor between Large Magellanic Cloud (LMC) and foreground objects. However, the objects are strongly clustered and appear to be associated with the pulsational instability strips of LMC Pop. I and II variables. When combined with the ULA variables of Buchler et al., a total of 20 objects fall close to the classical Cepheid instability strip. However, they appear to fall on parallel period-magnitude (PM) relations that are shifted to slightly higher magnitude which would confer them a different evolutionary status. Low-amplitude RV Tauri and Pop. II Cepheids have been uncovered that do not appear in the MACHO or OGLE catalogs. Interestingly, a set of binaries seem to lie on a PM relation that is essentially parallel to that of the RV Tauri/Pop. II Cepheids.

Implementation of sunshine sports in secondary schools in Tianjin ...

African Journals Online (AJOL)

A total of 450 physical education (PE) teachers in 34 secondary schools drawn from six districts in Tianjin participated in the study. ... schools in Tianjin met the official requirement for teaching sunshine sports, except during examination period in which 80% of PE classes were substituted by other 'academic' lessons. A total ...

An application of the variable-r method to subpopulation growth rates in a 19th century agricultural population

Directory of Open Access Journals (Sweden)

Corey Sparks

2009-07-01

Full Text Available This paper presents an analysis of the differential growth rates of the farming and non-farming segments of a rural Scottish community during the 19th and early 20th centuries using the variable-r method allowing for net migration. Using this method, I find that the farming population of Orkney, Scotland, showed less variability in their reproduction and growth rates than the non-farming population during a period of net population decline. I conclude by suggesting that the variable-r method can be used in general cases where the relative growth of subpopulations or subpopulation reproduction is of interest.

Short-timescale variability in cataclysmic binaries

International Nuclear Information System (INIS)

Cordova, F.A.; Mason, K.O.

1982-01-01

Rapid variability, including flickering and pulsations, has been detected in cataclysmic binaries at optical and x-ray frequencies. In the case of the novalike variable TT Arietis, simultaneous observations reveal that the x-ray and optical flickering activity is strongly correlated, while short period pulsations are observed that occur at the same frequencies in both wavelength bands

Global bioevents and the question of periodicity

Science.gov (United States)

Sepkoski, J. John

The hypothesis of periodicity in extinction is an empirical claim that extinction events, while variable in magnitude, are regular in timing and therefore are serially dependent upon some single, ultimate cause with clocklike behavior. This hypothesis is controversal, in part because of questions regarding the identity and timing of certain extinction events and because of speculations concerning possible catastrophic extraterrestrial forcing mechanisms. New data on extinctions of marine animal genera are presented that display a high degree of periodicity in the Mesozoic and Cenozoic as well as a suggestion of nonstationary periodicity in the late Paleozoic. However, no periodicity is evident among the as yet poorly documented extinction events of the early and middle Paleozoic.

Thrombotic Microangiopathy with Skin Localization Secondary to Cytarabine-Daunorubicin Association: Report of a Case

Directory of Open Access Journals (Sweden)

S. Regragui

2012-01-01

Full Text Available The thrombotic microangiopathy is a syndrome characterized by the combination of mechanical hemolytic anemia, peripheral thrombocytopenia, and organ failure of variable severity. In addition to the idiopathic form, several cases are identified as secondary to pregnancy, infections, disease systems, organ transplants, and cancer. Other forms are secondary to drugs including antimitotics. We report the case of a patient followed for acute myelogenous leukemia. She received induction chemotherapy combining daunorubicin and cytarabine, complicated by thrombotic thrombocytopenic purpura.

YSOVAR: Mid-infrared variability in the star-forming region Lynds 1688

Energy Technology Data Exchange (ETDEWEB)

Günther, H. M.; Poppenhaeger, K.; Wolk, S. J.; Hora, J. L. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Cody, A. M. [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Covey, K. R. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Hillenbrand, L. A. [Department of Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Plavchan, P. [NASA Exoplanet Science Institute, California Institute of Technology, 770 South Wilson Avenue, Pasadena, CA 91125 (United States); Rebull, L. M.; Stauffer, J. R. [Spitzer Science Center/Caltech, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Allen, L. [National Optical Astronomy Observatories, Tucson, AZ 85719 (United States); Bayo, A. [Max Planck Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Gutermuth, R. A. [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Meng, H. Y. A. [Infrared Processing and Analysis Center, California Institute of Technology, MC 100-22, 770 South Wilson Avenue, Pasadena, CA 91125 (United States); Morales-Calderón, M. [Centro de Astrobiología (INTA-CSIC), ESAC Campus, P.O. Box 78, E-28691 Villanueva de la Canada (Spain); Parks, J. R. [Department of Physics and Astronomy, Georgia State University, 25 Park Place South, Atlanta, GA 30303 (United States); Song, Inseok, E-mail: hguenther@cfa.harvard.edu [Physics and Astronomy Department, University of Georgia, Athens, GA 30602-2451 (United States)

2014-12-01

The emission from young stellar objects (YSOs) in the mid-infrared (mid-IR) is dominated by the inner rim of their circumstellar disks. We present IR data from the Young Stellar Object VARiability (YSOVAR) survey of ∼800 objects in the direction of the Lynds 1688 (L1688) star-forming region over four visibility windows spanning 1.6 yr using the Spitzer Space Telescope in its warm mission phase. Among all light curves, 57 sources are cluster members identified based on their spectral energy distribution and X-ray emission. Almost all cluster members show significant variability. The amplitude of the variability is larger in more embedded YSOs. Ten out of 57 cluster members have periodic variations in the light curves with periods typically between three and seven days, but even for those sources, significant variability in addition to the periodic signal can be seen. No period is stable over 1.6 yr. Nonperiodic light curves often still show a preferred timescale of variability that is longer for more embedded sources. About half of all sources exhibit redder colors in a fainter state. This is compatible with time-variable absorption toward the YSO. The other half becomes bluer when fainter. These colors can only be explained with significant changes in the structure of the inner disk. No relation between mid-IR variability and stellar effective temperature or X-ray spectrum is found.

Infection due to Mycobacterium bovis in common variable immunodeficiency

Directory of Open Access Journals (Sweden)

Diana Andrea Herrera-Sánchez

2015-02-01

Full Text Available Common variable immunodeficiency (CVID is an heterogeneous group of disorders characterized by impaired antibody production. It shows a wide spectrum of manifestations including severe and recurrent respiratory infections (Streptococcus pneumoniae, Haemophilus and gastrointestinal (Campylobacter jejuni, rotavirus and Giardia lamblia. Viral infections caused by herpes zoster, cytomegalovirus (CMV and hepatitis C are rare. The opportunistic agents such as CMV, Pneumocystis jirovecii, cryptococcus and atypical mycobacteria have been reported as isolated cases. This paper reports the case of a 38-year-old female patient, who began six years before with weight loss of 7 kg in six months, fatigue, weakness, sweating, fever and abdominal pain. Furthermore, patient had intestinal obstruction and abdominal CT showed mesenteric lymph growth. The mesenteric lymph node biopsy revealed positives Mycobacterium PCR, Ziehl-Neelsen staining and culture for M. bovis. In the laparotomy postoperative period was complicated with nosocomial pneumonia, requiring mechanical ventilation and tracheostomy. Two years later, she developed right renal abscess that required surgical drainage, once again with a positive culture for Mycobacterium bovis. She was referred to highly specialized hospital and we documented panhypogammaglobulinemia and lymphopenia. Secondary causes of hypogammaglobulinemia were ruled out and common variable immunodeficiency (CVID was confirmed, we started IVIG replacement. Four years later she developed mixed cellularity Hodgkin’s lymphoma. Until today she continues with IVIG and chemotherapy. This report of a patient with CVID and Mycobacterium bovis infection, a unusual association, shows the cellular immunity susceptibility in this immunodeficiency, additional to the humoral defect.

Sedentary behaviour across the primary-secondary school transition: A systematic review.

Science.gov (United States)

Pearson, Natalie; Haycraft, Emma; P Johnston, Julie; Atkin, Andrew J

2017-01-01

The transition from primary/middle school to secondary/high school is likely to be a key period in children's development, characterised by significant changes in their social and physical environment. However, little is known about the changes in sedentary behaviour that accompany this transition. This review aimed to identify, critically appraise and summarise the evidence on changes in sedentary behaviour across the primary - secondary school transition. Published English language studies were located from computerised and manual searches in 2015. Inclusion criteria specified a longitudinal design, baseline assessment when children were in primary/middle school with at least one follow-up during secondary/high school and a measure of sedentary behaviour at both (or all) points of assessment. Based on data from 11 articles (19 independent samples), tracking coefficients were typically in the range of 0.3 to 0.5 and relatively consistent across the different sedentary behaviours examined and durations of follow-up. Both screen-based sedentary behaviour and overall sedentary time increased during the school transition. Overall there was an increase of approximately 10-20min per day per year in accelerometer-assessed sedentary time. Consistent with the broader age-related changes in behaviour observed during this period, sedentary behaviour increases during the transition from primary/middle to secondary/high school. Investigating features of the social and physical environment that might exacerbate or attenuate this trend would be a valuable next step. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Secondary Restoration Control of Islanded Microgrids With Decentralized Event-triggered Strategy

DEFF Research Database (Denmark)

Guerrero, Josep M.; Chen, Meng; Xiao, Xiangning

2018-01-01

in the feedback control laws, the proposed control strategies just require the communication between distributed secondary controllers at some particular instants while having frequency and voltage restoration function and accurate active power sharing. The stability and inter-event interval are also analyzed......Distributed cooperative control methods attract more and more attention in microgrid secondary control because they are more reliable and flexible. However, the traditional methods rely on the periodic communication, which is neither economic nor efficient due to its large communication burden...... in this paper. An islanded microgrid test system is built in PSCAD/EMTDC to validate the proposed control strategies. It shows that the proposed secondary control strategies based on event-triggered approach can highly reduce the inter-agent communication....

Rapid climate variability during warm and cold periods in polar regions and Europe

DEFF Research Database (Denmark)

Masson-Delmotte, V.; Landais, A.; Combourieu-Nebout, N.

2005-01-01

Typical rapid climate events punctuating the last glacial period in Greenland, Europe and Antarctica are compared to two rapid events occurring under warmer conditions: (i) Dansgaard-Oeschger event 25, the first abrupt warming occurring during last glacial inception; (ii) 8.2 ka BP event, the only...... rapid cooling recorded during the Holocene in Greenland ice cores and in Ammersee, Germany. The rate of warming during previous warmer interglacial periods is estimated from polar ice cores to 1.5 °C per millennium, without abrupt changes. Climate change expected for the 21st century should however...

Periods and light curves of 16 Cepheid variables in IC 1613 not completed by Baade

International Nuclear Information System (INIS)

Carlson, G.; Sandage, A.

1990-01-01

New periods and light curves are presented for 16 of the faintest Cepheids in IC 1613 which had not been finished by Baade. Magnitudes have been reduced to Freedman's new photometric scale. The P-L relation is extended to periods of 2 days using these new data. Comparison of the total Cepheid data now available in IC 1613 with the data in LMC shows no significant slope difference in the two P-L relations for periods of less than 10 days despite the lower metallicity of the young stars in IC 1613. Fifty new faint Cepheid candidates have been found in IC 1613 by blinking plates not used for this purpose by Baade. Most of these stars will have probable periods of less than 2 days, which will eventually permit an extension of the P-L relation in IC 1613 to fainter magnitudes when the photometry and period determinations are completed. 18 refs

Measuring Variability in the Presence of Noise

Science.gov (United States)

Welsh, W. F.

Quantitative measurements of a variable signal in the presence of noise requires very careful attention to subtle affects which can easily bias the measurements. This is not limited to the low-count rate regime, nor is the bias error necessarily small. In this talk I will mention some of the dangers in applying standard techniques which are appropriate for high signal to noise data but fail in the cases where the S/N is low. I will discuss methods for correcting the bias in the these cases, both for periodic and non-periodic variability, and will introduce the concept of the ``filtered de-biased RMS''. I will also illustrate some common abuses of power spectrum interpretation. All of these points will be illustrated with examples from recent work on CV and AGN variability.

Impact Of Secondary-Primary Pumps Operating Sequence On The Electrical Power Supply System

International Nuclear Information System (INIS)

Suwoto; Rusdiyanto; Kiswanto

2001-01-01

The operating procedure of the reactor cooling system has decided that the primary cooling pump should be operated before secondary cooling pump as known primary-secondary pumps operating sequence. This decision is based on consideration that starting current of the primary pump is higher than secondary pump. Therefore, the primary-secondary pumps operating sequence can avoid the power supply system failure. However, this operating procedure has to take a consequence that in case of primary pump failure, the shutdown time period of the reaktor to be longer caused to re operate the primary pump has required that the running secondary pump should be shutted off. To solve this problem, an impact analysis of the secondary-primary pumps operating sequence on the electric power supply system was carried out to identify the revision possibility of the cooling pump operating procedure. The analysis by discussion of the measuring results of the secondary and primary pump starting current related to another electrical loads has been measured. From discussion it can be concluded that secondary-primary pumps operating sequence has no impact to failure in electric power supply system

A possible close supermassive black-hole binary in a quasar with optical periodicity.

Science.gov (United States)

Graham, Matthew J; Djorgovski, S G; Stern, Daniel; Glikman, Eilat; Drake, Andrew J; Mahabal, Ashish A; Donalek, Ciro; Larson, Steve; Christensen, Eric

2015-02-05

Quasars have long been known to be variable sources at all wavelengths. Their optical variability is stochastic and can be due to a variety of physical mechanisms; it is also well-described statistically in terms of a damped random walk model. The recent availability of large collections of astronomical time series of flux measurements (light curves) offers new data sets for a systematic exploration of quasar variability. Here we report the detection of a strong, smooth periodic signal in the optical variability of the quasar PG 1302-102 with a mean observed period of 1,884 ± 88 days. It was identified in a search for periodic variability in a data set of light curves for 247,000 known, spectroscopically confirmed quasars with a temporal baseline of about 9 years. Although the interpretation of this phenomenon is still uncertain, the most plausible mechanisms involve a binary system of two supermassive black holes with a subparsec separation. Such systems are an expected consequence of galaxy mergers and can provide important constraints on models of galaxy formation and evolution.

Secondary Channel Bifurcation Geometry: A Multi-dimensional Problem

Science.gov (United States)

Gaeuman, D.; Stewart, R. L.

2017-12-01

The construction of secondary channels (or side channels) is a popular strategy for increasing aquatic habitat complexity in managed rivers. Such channels, however, frequently experience aggradation that prevents surface water from entering the side channels near their bifurcation points during periods of relatively low discharge. This failure to maintain an uninterrupted surface water connection with the main channel can reduce the habitat value of side channels for fish species that prefer lotic conditions. Various factors have been proposed as potential controls on the fate of side channels, including water surface slope differences between the main and secondary channels, the presence of main channel secondary circulation, transverse bed slopes, and bifurcation angle. A quantitative assessment of more than 50 natural and constructed secondary channels in the Trinity River of northern California indicates that bifurcations can assume a variety of configurations that are formed by different processes and whose longevity is governed by different sets of factors. Moreover, factors such as bifurcation angle and water surface slope vary with discharge level and are continuously distributed in space, such that they must be viewed as a multi-dimensional field rather than a single-valued attribute that can be assigned to a particular bifurcation.

Daily Course of CO2 Fluxes in the Atmosphere-Water System and Variable Fluorescence of Phytoplankton during the Open-Water Period for Lake Baikal according to Long-Term Measurements

Science.gov (United States)

Zavoruev, V. V.; Domysheva, V. M.; Pestunov, D. A.; Sakirko, M. V.; Panchenko, M. V.

2018-04-01

The process of gas exchange of CO2 in the atmosphere-water system and its relation to the daily course of variable fluorescence of phytoplankton is studied on the basis of long-term (2004-2014) measurements during the open water period for Lake Baikal. It is found that the decrease in photosynthetic activity of plankton is almost synchronous to the increase in the CO2 flux from atmosphere to water. It follows from comparison of the spring and summer data with December measurements that the daily decrease in variable fluorescence of phytoplankton is caused by the internal daily rhythm of the photosynthetic activity of plankton.

SECONDARY PHYSICAL EDUCATION AVOIDANCE AND GENDER: PROBLEMS AND ANTIDOTES

Directory of Open Access Journals (Sweden)

Thomas Ryan

2012-07-01

Full Text Available Our goal was to locate and evaluate the barriers that impact and cause females to avoid secondary elective physical education courses. We sought to find answers to stop the further decline of female enrolment in secondary physical education by looking into curricula, program and instructional variables. Anecdotal evidence informed this study which was very much exploratory, building upon several key facts. First, Ontario (Canada secondary students are only required to take one credit (course in physical education in order to graduate and second, most students take the required physical education course in grade nine which is their first year of high school. Following this there is an average of 10% fewer females in every physical education class in the province of Ontario and only an average of 12% are enrolled in physical education each year. Several issues were identified and explored including self-confidence; motivation; perceived value of physical activity; opportunities for physical activity; marking scheme; competition; co-ed classes; teaching approach; and peers as possible problems and solutions.

Climate variability in Andalusia (southern Spain during the period 1701–1850 based on documentary sources: evaluation and comparison with climate model simulations

Directory of Open Access Journals (Sweden)

J. P. Montávez Gómez

2012-01-01

Full Text Available In this work, a reconstruction of climatic conditions in Andalusia (southern Iberian Peninsula during the period 1701–1850, as well as an evaluation of its associated uncertainties, is presented. This period is interesting because it is characterized by a minimum in solar irradiance (Dalton Minimum, around 1800, as well as intense volcanic activity (for instance, the eruption of Tambora in 1815, at a time when any increase in atmospheric CO2 concentrations was of minor importance. The reconstruction is based on the analysis of a wide variety of documentary data. The reconstruction methodology is based on counting the number of extreme events in the past, and inferring mean value and standard deviation using the assumption of normal distribution for the seasonal means of climate variables. This reconstruction methodology is tested within the pseudoreality of a high-resolution paleoclimate simulation performed with the regional climate model MM5 coupled to the global model ECHO-G. The results show that the reconstructions are influenced by the reference period chosen and the threshold values used to define extreme values. This creates uncertainties which are assessed within the context of climate simulation. An ensemble of reconstructions was obtained using two different reference periods (1885–1915 and 1960–1990 and two pairs of percentiles as threshold values (10–90 and 25–75. The results correspond to winter temperature, and winter, spring and autumn rainfall, and they are compared with simulations of the climate model for the considered period. The mean value of winter temperature for the period 1781–1850 was 10.6 ± 0.1 °C (11.0 °C for the reference period 1960–1990. The mean value of winter rainfall for the period 1701–1850 was 267 ± 18 mm (224 mm for 1960–1990. The mean values of spring and autumn rainfall were 164 ± 11 and 194 ± 16 mm (129 and 162 mm for 1960–1990, respectively. Comparison of the distribution

Inherent characteristics of sawtooth cycles can explain different glacial periodicities

NARCIS (Netherlands)

Omta, A.W.; Kooi, B.W.; van Voorn, G.A.K.; Rickaby, R.E.M; Follows, M.J.

2016-01-01

At the Mid-Pleistocene Transition about 1 Ma, the dominant periodicity of the glacial-interglacial cycles shifted from ~40 to ~100 kyr. Here, we use a previously developed mathematical model to investigate the possible dynamical origin of these different periodicities. The model has two variables,

Photometry of red variables in 47 Tucanae

International Nuclear Information System (INIS)

Fox, M.W.

1982-01-01

BVRI observations of known and suspected variables in the globular cluster 47 Tuc are described. Twelve period determinations were made, seven of which are new. The non-Mira stars are found to vary in a semi-regular manner, regardless of period. Values of Tsub(eff), Msub(bol) and Q, the pulsation constant, are derived by combining the BVRI with JHKL observations made near the same epoch. The results strongly favour pulsation in an overtone mode for both the Mira and semi-regular variables in 47 Tuc. There is also evidence of mode 'switching' for V4. (author)

The Varied Variability of PKS 0736+017

Science.gov (United States)

Clements, S. D.; Cubides, L. A.; Greiwe, C. L.; Habermas, K. S.; Jenks, A. K.; Long, A. M.; Patel, J. A.; Torres, Y. V.

2003-05-01

The flat spectrum radio quasar PKS 0736+017 has been an exciting observing target, exhibiting diverse optical variability behaviors and even sharing its field one evening with a minor planet. The behavior of PKS 0736+017 has included persistently faint and quiescent periods, episodes of quasi-periodic microvariability, dramatic flaring events, and periods of unusual oscillations. These assorted behaviors are examined, with particular emphasis on the quasi-periodic variations and unusual oscillations that accompanied a dramatic flare.

Secondary Pollutants in the Lake Tahoe Basin, USA

Science.gov (United States)

Zielinska, B.; Bytnerowicz, A.; Gertler, A.; McDaniel, M.; Burley, J. D.

2013-12-01

Lake Tahoe, located at 6,225 ft. (1,897 m) in the Sierra Nevada mountain range, is the largest alpine lake in North America. Known for the clarity of its water and the panorama of surrounding mountains on all sides, Lake Tahoe is a prime tourist attraction in the California - Nevada area. However, the Lake Tahoe Basin is facing significant problems in air quality and declining water clarity. In July 21 - 26, 2012, we conducted a field study in the Basin designed to characterize the precursors and pathways of secondary pollutant formation, including ozone, secondary organic aerosol (SOA) and ammonium nitrate. Four strategic sampling sites were selected inside the Basin; two of these sites were located at high elevation (one each on the western and eastern sides of the Basin) and two were positioned near the Lake level. Ozone and NO/NO2 concentrations were continuously measured. With a resolution of several hours over a 6-day sampling period we collected canister samples for detailed speciation of volatile organic compounds (VOC), 2,4-dinitrophenylhydrazine (DNPH) impregnated Sep-Pak cartridges for analysis of carbonyl compounds and honeycomb denuder/filter pack samples for measurement of concentrations of ammonia, nitrous acid, nitric acid, and fine particulate ammonium nitrate. We also collected PM2.5 Teflon and quartz filter samples for measurements of mass, organic and elemental carbon (OC/EC) concentrations and speciation of organic compounds. Whereas the concentrations of lower molecular weight (mw) C2 - C3 hydrocarbons were generally the highest in all sampling sites, ranging from 25 to 76% of the total measured VOC (over 70 species from C2 to C10), the concentrations of biogenic hydrocarbons, isoprene and α-pinene were significant, ranging from 1.4 to 26% and 1.5 to 30%, respectively, of the total VOC, depending on the site and sampling period. For comparison, the sum of benzene, toluene, ethylbenzene and xylenes (BTEX) constituted from 2.5 to 37% of the

Influence of Body Composition on Gait Kinetics throughout Pregnancy and Postpartum Period

Science.gov (United States)

Branco, Marco; Santos-Rocha, Rita; Vieira, Filomena; Silva, Maria-Raquel; Aguiar, Liliana; Veloso, António P.

2016-01-01

Pregnancy leads to several changes in body composition and morphology of women. It is not clear whether the biomechanical changes occurring in this period are due exclusively to body composition and size or to other physiological factors. The purpose was to quantify the morphology and body composition of women throughout pregnancy and in the postpartum period and identify the contribution of these parameters on the lower limb joints kinetic during gait. Eleven women were assessed longitudinally, regarding anthropometric, body composition, and kinetic parameters of gait. Body composition and body dimensions showed a significant increase during pregnancy and a decrease in the postpartum period. In the postpartum period, body composition was similar to the 1st trimester, except for triceps skinfold, total calf area, and body mass index, with higher results than at the beginning of pregnancy. Regression models were developed to predict women's internal loading through anthropometric variables. Four models include variables associated with the amount of fat; four models include variables related to overall body weight; three models include fat-free mass; one model includes the shape of the trunk as a predictor variable. Changes in maternal body composition and morphology largely determine kinetic dynamics of the joints in pregnant women. PMID:27073713

Deciphering Periodic Methanol Masers

Science.gov (United States)

Stecklum, Bringfried; Caratti o Garatti, Alessio; Henning, Thomas; Hodapp, Klaus; Hopp, Ulrich; Kraus, Alex; Linz, Hendrik; Sanna, Alberto; Sobolev, Andrej; Wolf, Verena

2018-05-01

Impressive progress has been made in recent years on massive star formation, yet the involved high optical depths even at submm/mm wavelengths make it difficult to reveal its details. Recently, accretion bursts of massive YSOs have been identified to cause flares of Class II methanol masers (methanol masers for short) due to enhanced mid-IR pumping. This opens a new window to protostellar accretion variability, and implies that periodic methanol masers hint at cyclic accretion. Pinning down the cause of the periodicity requires joint IR and radio monitoring. We derived the first IR light curve of a periodic maser host from NEOWISE data. The source, G107.298+5.639, is an intermediate-mass YSO hosting methanol and water masers which flare every 34.5 days. Our recent joint K-band and radio observations yielded first but marginal evidence for a phase lag between the rise of IR and maser emission, respectively, and revealed that both NEOWISE and K-band light curves are strongly affected by the light echo from the ambient dust. Both the superior resolution of IRAC over NEOWISE and the longer wavelengths compared to our ground-based imaging are required to inhibit the distractive contamination by the light echo. Thus, we ask for IRAC monitoring of G107 to cover one flare cycle, in tandem with 100-m Effelsberg and 2-m Wendelstein radio and NIR observations to obtain the first high-quality synoptic measurements of this kind of sources. The IR-maser phase lag, the intrinsic shape of the IR light curves and their possible color variation during the cycle allow us to constrain models for the periodic maser excitation. Since methanol masers are signposts of intermediate-mass and massive YSOs, deciphering their variability offers a clue to the dynamics of the accretion-mediated growth of massive stars and their feedback onto the immediate natal environment. The Spitzer light curve of such a maser-hosting YSO would be a legacy science product of the mission.

A comparative study of conventional and supercritical fluid extraction methods for the recovery of secondary metabolites from Syzygium campanulatum Korth#

Science.gov (United States)

Memon, Abdul Hakeem; Hamil, Mohammad Shahrul Ridzuan; Laghari, Madeeha; Rithwan, Fahim; Zhari, Salman; Saeed, Mohammed Ali Ahmed; Ismail, Zhari; Majid, Amin Malik Shah Abdul

2016-01-01

Syzygium campanulatum Korth is a plant, which is a rich source of secondary metabolites (especially flavanones, chalcone, and triterpenoids). In our present study, three conventional solvent extraction (CSE) techniques and supercritical fluid extraction (SFE) techniques were performed to achieve a maximum recovery of two flavanones, chalcone, and two triterpenoids from S. campanulatum leaves. Furthermore, a Box-Behnken design was constructed for the SFE technique using pressure, temperature, and particle size as independent variables, and yields of crude extract, individual and total secondary metabolites as the dependent variables. In the CSE procedure, twenty extracts were produced using ten different solvents and three techniques (maceration, soxhletion, and reflux). An enriched extract of five secondary metabolites was collected using n-hexane:methanol (1:1) soxhletion. Using food-grade ethanol as a modifier, the SFE methods produced a higher recovery (25.5%‒84.9%) of selected secondary metabolites as compared to the CSE techniques (0.92%‒66.00%). PMID:27604860

A comparative study of conventional and supercritical fluid extraction methods for the recovery of secondary metabolites from Syzygium campanulatum Korth.

Science.gov (United States)

Memon, Abdul Hakeem; Hamil, Mohammad Shahrul Ridzuan; Laghari, Madeeha; Rithwan, Fahim; Zhari, Salman; Saeed, Mohammed Ali Ahmed; Ismail, Zhari; Majid, Amin Malik Shah Abdul

2016-09-01

Syzygium campanulatum Korth is a plant, which is a rich source of secondary metabolites (especially flavanones, chalcone, and triterpenoids). In our present study, three conventional solvent extraction (CSE) techniques and supercritical fluid extraction (SFE) techniques were performed to achieve a maximum recovery of two flavanones, chalcone, and two triterpenoids from S. campanulatum leaves. Furthermore, a Box-Behnken design was constructed for the SFE technique using pressure, temperature, and particle size as independent variables, and yields of crude extract, individual and total secondary metabolites as the dependent variables. In the CSE procedure, twenty extracts were produced using ten different solvents and three techniques (maceration, soxhletion, and reflux). An enriched extract of five secondary metabolites was collected using n-hexane:methanol (1:1) soxhletion. Using food-grade ethanol as a modifier, the SFE methods produced a higher recovery (25.5%‒84.9%) of selected secondary metabolites as compared to the CSE techniques (0.92%‒66.00%).

Analysis Of Supporting Factors On Foreign Direct Investment And Its Impact Toward Indonesian Employment And Export Performance Period 2005-2015

Directory of Open Access Journals (Sweden)

Suharto

2017-09-01

Full Text Available This research analyzes effects of foreign direct investment and Its Impact toward employment and export performance in Indonesia 2005-2015. This research with secondary data focuses on the Supporting factors in which attract foreign direct investment into Indonesia. This research focused on the problem First the impact of labor export results economic growth rate exchange rate inflation rate interest rate and tax toward foreign direct investment second the impact of foreign direct investment on the expansion of employment and export performance in Indonesia during the period 2005-2015. The result of this research explains that variables of human resourceslabor and export performance give positive effect as significantly to attracting foreign direct investment in Indonesia. While foreign direct investment in Indonesia gives positive effect to employment creation and to export performance.

Pulmonary involvement of secondary syphilis.

Science.gov (United States)

Ogawa, Yoshihiko; Imai, Yuichiro; Yoshihara, Shingo; Fujikura, Hiroyuki; Hirai, Nobuyasu; Sato, Masatoshi; Ogawa, Taku; Uno, Kenji; Kasahara, Kei; Yano, Hisakazu; Mikasa, Keiichi

2018-01-01

Pulmonary involvement in secondary syphilis is considered a rare occurrence; however, the number of cases has increased in the 2000s. This is likely due to the increased use of computed tomography scans and molecular diagnostic testing. We report a case of an HIV-positive man with pleural chest pain and bilateral subpleural nodules on chest computed tomography. His rapid plasma reagin and Treponema pallidum hemagglutination tests were positive, and the specimen of one of the pulmonary nodules obtained by transthoracic biopsy was positive for the polA gene of Treponema pallidum. Since clinical manifestations of syphilis are highly variable, clinicians should bear in mind that pleural chest pain with bilateral subpleural nodules can be caused by pulmonary syphilis.

Aerodynamic analysis of the Darrieus rotor including secondary effects

Science.gov (United States)

Paraschivoiu, I.; Delclaux, F.; Fraunie, P.; Beguier, C.

1983-10-01

An aerodynamic analysis is made of two variants of the two-actuator-disk theory for modeling the Darrieus wind turbine. The double-multiple-streamtube model with constant and variable interference factors, including secondary effects, is examined for a Darrieus rotor. The influence of the secondary effects, namely, the blade geometry and profile type, the rotating tower, and the presence of struts and aerodynamic spoilers, is relatively significant, especially at high tip-speed ratios. Variation of the induced velocity as a function of the azimuthal angle allows a more accurate calculation of the aerodynamic loads on the downwind zone of the rotor with respect to the assumed constant interference factors. The theoretical results were compared with available experimental data for the Magdalen Islands wind turbine and Sandia-type machines (straight-line/circular-arc shape).

The variability in Oxford hip and knee scores in the preoperative period: is there an ideal time to score?

Science.gov (United States)

Quah, C; Holmes, D; Khan, T; Cockshott, S; Lewis, J; Stephen, A

2018-01-01

Background All NHS-funded providers are required to collect and report patient-reported outcome measures for hip and knee arthroplasty. Although there are established guidelines for timing such measures following arthroplasty, there are no specific time-points for collection in the preoperative period. The primary aim of this study was to identify whether there was a significant amount of variability in the Oxford hip and knee scores prior to surgical intervention when completed in the outpatient clinic at the time of listing for arthroplasty or when completed at the preoperative assessment clinic. Methods A prospective cohort study of patients listed for primary hip or knee arthroplasty was conducted. Patients were asked to fill in a preoperative Oxford score in the outpatient clinic at the time of listing. They were then invited to fill in the official outcome measures questionnaire at the preoperative assessment clinic. The postoperative Oxford score was then completed when the patient was seen again at their postoperative follow up in clinic. Results Of the total of 109 patients included in this study period, there were 18 (17%) who had a worse score of 4 or more points difference and 43 (39.4%) who had an improvement of 4 or more points difference when the scores were compared between time of listing at the outpatient and at the preoperative assessment clinic. There was a statistically significant difference (P = 0.0054) in the mean Oxford scores. Conclusions The results of our study suggest that there should be standardisation of timing for completing the preoperative patient-reported outcome measures.

Comparing Building and Neighborhood-Scale Variability of CO₂ and O₃ to Inform Deployment Considerations for Low-Cost Sensor System Use.

Science.gov (United States)

Collier-Oxandale, Ashley; Coffey, Evan; Thorson, Jacob; Johnston, Jill; Hannigan, Michael

2018-04-26

The increased use of low-cost air quality sensor systems, particularly by communities, calls for the further development of best-practices to ensure these systems collect usable data. One area identified as requiring more attention is that of deployment logistics, that is, how to select deployment sites and how to strategically place sensors at these sites. Given that sensors are often placed at homes and businesses, ideal placement is not always possible. Considerations such as convenience, access, aesthetics, and safety are also important. To explore this issue, we placed multiple sensor systems at an existing field site allowing us to examine both neighborhood-level and building-level variability during a concurrent period for CO₂ (a primary pollutant) and O₃ (a secondary pollutant). In line with previous studies, we found that local and transported emissions as well as thermal differences in sensor systems drive variability, particularly for high-time resolution data. While this level of variability is unlikely to affect data on larger averaging scales, this variability could impact analysis if the user is interested in high-time resolution or examining local sources. However, with thoughtful placement and thorough documentation, high-time resolution data at the neighborhood level has the potential to provide us with entirely new information on local air quality trends and emissions.

Partitioning the impacts of spatial and climatological rainfall variability in urban drainage modeling

Science.gov (United States)

Peleg, Nadav; Blumensaat, Frank; Molnar, Peter; Fatichi, Simone; Burlando, Paolo

2017-03-01

The performance of urban drainage systems is typically examined using hydrological and hydrodynamic models where rainfall input is uniformly distributed, i.e., derived from a single or very few rain gauges. When models are fed with a single uniformly distributed rainfall realization, the response of the urban drainage system to the rainfall variability remains unexplored. The goal of this study was to understand how climate variability and spatial rainfall variability, jointly or individually considered, affect the response of a calibrated hydrodynamic urban drainage model. A stochastic spatially distributed rainfall generator (STREAP - Space-Time Realizations of Areal Precipitation) was used to simulate many realizations of rainfall for a 30-year period, accounting for both climate variability and spatial rainfall variability. The generated rainfall ensemble was used as input into a calibrated hydrodynamic model (EPA SWMM - the US EPA's Storm Water Management Model) to simulate surface runoff and channel flow in a small urban catchment in the city of Lucerne, Switzerland. The variability of peak flows in response to rainfall of different return periods was evaluated at three different locations in the urban drainage network and partitioned among its sources. The main contribution to the total flow variability was found to originate from the natural climate variability (on average over 74 %). In addition, the relative contribution of the spatial rainfall variability to the total flow variability was found to increase with longer return periods. This suggests that while the use of spatially distributed rainfall data can supply valuable information for sewer network design (typically based on rainfall with return periods from 5 to 15 years), there is a more pronounced relevance when conducting flood risk assessments for larger return periods. The results show the importance of using multiple distributed rainfall realizations in urban hydrology studies to capture the

Detection of secondary structure elements in proteins by hydrophobic cluster analysis.

Science.gov (United States)

Woodcock, S; Mornon, J P; Henrissat, B

1992-10-01

Hydrophobic cluster analysis (HCA) is a protein sequence comparison method based on alpha-helical representations of the sequences where the size, shape and orientation of the clusters of hydrophobic residues are primarily compared. The effectiveness of HCA has been suggested to originate from its potential ability to focus on the residues forming the hydrophobic core of globular proteins. We have addressed the robustness of the bidimensional representation used for HCA in its ability to detect the regular secondary structure elements of proteins. Various parameters have been studied such as those governing cluster size and limits, the hydrophobic residues constituting the clusters as well as the potential shift of the cluster positions with respect to the position of the regular secondary structure elements. The following results have been found to support the alpha-helical bidimensional representation used in HCA: (i) there is a positive correlation (clearly above background noise) between the hydrophobic clusters and the regular secondary structure elements in proteins; (ii) the hydrophobic clusters are centred on the regular secondary structure elements; (iii) the pitch of the helical representation which gives the best correspondence is that of an alpha-helix. The correspondence between hydrophobic clusters and regular secondary structure elements suggests a way to implement variable gap penalties during the automatic alignment of protein sequences.

On Quasi-Periodic Brightness Variations of P Cygni

Science.gov (United States)

Kochiashvili, N.; Beradze, S.; Natsvlishvili, R.; Kochiashvili, I.; Vardosanidze, M.; Pannicke, A.

2018-03-01

Until recent decades, it was considered that all Luminous Blue Variables are single massive and high luminosity stars. Now for several of them a companion has been found. The opinion exists that P Cygni also has a companion with an orbital period of about seven years. In accordance with this hypothesis, a known powerful eruption occurred near the periastron point. P Cygni, as well as several other well-known Luminous Blue Variable (LBV) stars, is a so-called "Supernova Impostor" because it survived after a powerful outburst. However, there were cases during the last decade when a LBV star survived after a powerful giant eruption, and then after a few years, explode as a supernova. Because the real reason for the great eruption and characteristic light variability of LBV, including P Cygni, is not established yet, any kind of photometric and spectral observational data is very significant. We present the results of analysis of the long-term photometric observations of hypergiant P Cygni. On the basis of these data, different quasi-periodic brightness changes of the star were revealed.

Reflections on Teaching Periodic Table Concepts: A Case Study of Selected Schools in South Africa

Science.gov (United States)

Mokiwa, Hamza Omari

2017-01-01

The Periodic Table of Elements is central to the study of modern Physics and Chemistry. It is however, considered by teachers as difficult to teach. This paper reports on a case study exploring reflections on teaching periodic table concepts in five secondary schools from South Africa. Qualitative methodology of interviews and document analysis…

The influence of solar system oscillation on the variability of the total solar irradiance

Science.gov (United States)

Yndestad, Harald; Solheim, Jan-Erik

2017-02-01

Total solar irradiance (TSI) is the primary quantity of energy that is provided to the Earth. The properties of the TSI variability are critical for understanding the cause of the irradiation variability and its expected influence on climate variations. A deterministic property of TSI variability can provide information about future irradiation variability and expected long-term climate variation, whereas a non-deterministic variability can only explain the past. This study of solar variability is based on an analysis of two TSI data series, one since 1700 A.D. and one since 1000 A.D.; a sunspot data series since 1610 A.D.; and a solar orbit data series from 1000 A.D. The study is based on a wavelet spectrum analysis. First, the TSI data series are transformed into a wavelet spectrum. Then, the wavelet spectrum is transformed into an autocorrelation spectrum to identify stationary, subharmonic and coincidence periods in the TSI variability. The results indicate that the TSI and sunspot data series have periodic cycles that are correlated with the oscillations of the solar position relative to the barycenter of the solar system, which is controlled by gravity force variations from the large planets Jupiter, Saturn, Uranus and Neptune. A possible explanation for solar activity variations is forced oscillations between the large planets and the solar dynamo. We find that a stationary component of the solar variability is controlled by the 12-year Jupiter period and the 84-year Uranus period with subharmonics. For TSI and sunspot variations, we find stationary periods related to the 84-year Uranus period. Deterministic models based on the stationary periods confirm the results through a close relation to known long solar minima since 1000 A.D. and suggest a modern maximum period from 1940 to 2015. The model computes a new Dalton-type sunspot minimum from approximately 2025 to 2050 and a new Dalton-type period TSI minimum from approximately 2040 to 2065.

RE-SEARCHING SECONDARY TEACHER TRAINEES IN DISTANCE EDUCATION AND FACE-TO-FACE MODE: Study of Their Background Variables, Personal Characteristics and Academic Performance

Directory of Open Access Journals (Sweden)

Mamta GARG

2011-07-01

Full Text Available The present investigation was conducted to describe and compare the background variables, personal characteristics and academic performance of secondary teacher trainees in distance education and face-to-face mode. The results indicated that teacher trainees in distance education differed from their counterparts in age, marital status, sex and socio-economic status. Distance trainees outperformed the on-campus trainees on their preference for left-hemispheric styles of learning and thinking, budgeting time, learning motivation, overall study habits, academic motivation, attitude towards education, work methods, interpersonal relations, and on their perception about relevance of course content of theory papers in B.Ed., but on-campus trainees outperformed distance trainees on preference for right-hemispheric learning styles, need for achievement, motivation for sports, attitude towards teaching profession, child-centered practices, teachers, overall attitude towards teaching along with their perception for development of teaching skills and attitude, personality development during B.Ed. course. In academic performance distance trainees lag behind the on-campus trainee in their marks in theory papers, skills in teaching and in aggregate.

Clinical and acoustical variability in hypokinetic dysarthria

International Nuclear Information System (INIS)

Metter, E.J.; Hanson, W.R.

1986-01-01

Ten male patients with parkinsonism secondary to Parkinson's disease or progressive supranuclear palsy had clinical neurological, speech, and acoustical speech evaluations. In addition, seven of the patients were evaluated by x-ray computed tomography (CT) and (F-18)-fluorodeoxyglucose (FDG) positron emission tomography (PET). Extensive variability of speech features, both clinical and acoustical, were found and seemed to be independent of the severity of any parkinsonian sign, CT, or FDG PET. In addition, little relationship existed between the variability across each measured speech feature. What appeared to be important for the appearance of abnormal acoustic measures was the degree of overall severity of the dysarthria. These observations suggest that a better understanding of hypokinetic dysarthria may result from more extensive examination of the variability between patients. Emphasizing a specific feature such as rapid speaking rate in characterizing hypokinetic dysarthria focuses on a single and inconstant finding in a complex speech pattern

Secondary School under Educational Space Transformation in Modern Ukraine

Directory of Open Access Journals (Sweden)

A. Makhinko

2017-12-01

Full Text Available The article is dedicated to the reforms in secondary education of Ukraine during the period from establishment of the independent country in early 1990s till the beginning of the 21st Cent. The legislative and normative base, as well as practice of mplementing its key points, were analyzed. The author concludes that this period is characterized by an intensive reform and adjustment to global standards. A particular attention is paid to problems of high schools in the countryside. Conclusions focus mainly on the results of the high school development and prospects for subsequent modernization of this sphere.

Personal Characteristics of Teachers, Situational Variables and Deliberations in Planning Instruction.

Science.gov (United States)

Kremer, Lya

This study reveals possible relationships among teachers' personality traits, situational variables, and deliberation characteristics in planning instruction. Dogmatism and locus of control perceptions were the personality traits studied, and the situations compared student teachers with elementary and secondary school teachers. Both groups were…

Discrete rate and variable power adaptation for underlay cognitive networks

KAUST Repository

Abdallah, Mohamed M.

2010-01-01

We consider the problem of maximizing the average spectral efficiency of a secondary link in underlay cognitive networks. In particular, we consider the network setting whereby the secondary transmitter employs discrete rate and variable power adaptation under the constraints of maximum average transmit power and maximum average interference power allowed at the primary receiver due to the existence of an interference link between the secondary transmitter and the primary receiver. We first find the optimal discrete rates assuming a predetermined partitioning of the signal-to-noise ratio (SNR) of both the secondary and interference links. We then present an iterative algorithm for finding a suboptimal partitioning of the SNR of the interference link assuming a fixed partitioning of the SNR of secondary link selected for the case where no interference link exists. Our numerical results show that the average spectral efficiency attained by using the iterative algorithm is close to that achieved by the computationally extensive exhaustive search method for the case of Rayleigh fading channels. In addition, our simulations show that selecting the optimal partitioning of the SNR of the secondary link assuming no interference link exists still achieves the maximum average spectral efficiency for the case where the average interference constraint is considered. © 2010 IEEE.

A comparison between girls' and boys' experiences of unwanted sexual behaviour in secondary schools

NARCIS (Netherlands)

Timmerman, G

Background This study examines gender differences (and similarities) in the context, meaning and effects of unwanted sexual behaviour in secondary schools. Purpose First, the study's purpose is exploration of variables that discriminate between girls' and boys' experiences of unwanted sexual

Secondary Forest Age and Tropical Forest Biomass Estimation Using TM

Science.gov (United States)

Nelson, R. F.; Kimes, D. S.; Salas, W. A.; Routhier, M.

1999-01-01

The age of secondary forests in the Amazon will become more critical with respect to the estimation of biomass and carbon budgets as tropical forest conversion continues. Multitemporal Thematic Mapper data were used to develop land cover histories for a 33,000 Square kM area near Ariquemes, Rondonia over a 7 year period from 1989-1995. The age of the secondary forest, a surrogate for the amount of biomass (or carbon) stored above-ground, was found to be unimportant in terms of biomass budget error rates in a forested TM scene which had undergone a 20% conversion to nonforest/agricultural cover types. In such a situation, the 80% of the scene still covered by primary forest accounted for over 98% of the scene biomass. The difference between secondary forest biomass estimates developed with and without age information were inconsequential relative to the estimate of biomass for the entire scene. However, in futuristic scenarios where all of the primary forest has been converted to agriculture and secondary forest (55% and 42% respectively), the ability to age secondary forest becomes critical. Depending on biomass accumulation rate assumptions, scene biomass budget errors on the order of -10% to +30% are likely if the age of the secondary forests are not taken into account. Single-date TM imagery cannot be used to accurately age secondary forests into single-year classes. A neural network utilizing TM band 2 and three TM spectral-texture measures (bands 3 and 5) predicted secondary forest age over a range of 0-7 years with an RMSE of 1.59 years and an R(Squared) (sub actual vs predicted) = 0.37. A proposal is made, based on a literature review, to use satellite imagery to identify general secondary forest age groups which, within group, exhibit relatively constant biomass accumulation rates.

Advances in Charge-Compensation in Secondary Ion Mass Spectrometry (SIMS)

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Hervig, R. L.; Chen, J.; Schauer, S.; Stanley, B. D.; Moore, G. M.; Roggensack, K.

2012-12-01

In secondary ion mass spectrometry (SIMS), a sample is bombarded by a charged particle beam (the primary ion) and sputtered positive or negative secondary ions are analyzed in a mass spectrometer. When the target is not conducting (like many geological materials), sample charging can result in variable deflection of secondary ions away from the mass spectrometer and a low, unstable, or absent signal. Applying a thin conducting coat (e.g., C, Au) to polished samples is required, and if the primary ion beam is negatively-charged, the build-up of negative charge can be alleviated by secondary electrons draining to the conducting coat at the edge of the crater (if a positive potential is applied to the sample for the collection of positive secondary ions) or accelerated away from the crater (if a negative potential is applied for negative ion study). Unless the sputtered crater in the conducting coat becomes too large, sample charging can be kept at a controllable level, and high-quality trace element analyses and isotope ratios have been obtained using this technique over the past 3+ decades. When a positive primary beam is used, the resulting build-up of positive charge in the sample requires an electron gun to deliver sufficient negative charge to the sputtered crater. While there are many examples of successful analyses using this approach, the purpose of this presentation is to describe a very simple technique for aligning the electron gun on Cameca nf and 1270/80 SIMS instruments. This method allows reproducible analyses of insulating phases with a Cs+ primary beam and detection of negative secondary ions. Normally, the filament voltage on the E-gun is the same as the sample voltage; thus electrons do not strike the sample except when a positive charge has built up (e.g., in the analysis crater!). In this method, we decrease the sample voltage by 3 or more kV, so that the impact energy of the electrons is sufficient to induce a cathodoluminescent (CL) image on an

Fast optical and X-ray variability in the UCXB 4U0614+09

Science.gov (United States)

Hakala, P. J.; Charles, P. A.; Muhli, P.

2011-09-01

We present results from several years of fast optical photometry of 4U0614+091 (V1055 Orionis), a candidate ultracompact X-ray binary most likely consisting of a neutron star and a degenerate secondary. We find evidence for strong accretion-driven variability at all epochs, which manifests itself as red noise. This flickering produces transient peaks in the observed power spectrum in the 15-65 min period range. Only in one of our 12 optical data sets can we see evidence for a period that cannot be reproduced using the red noise model. This period of 51 min coincides with the strongest period detected by Shahbaz et al. and can thus be taken as the prime candidate for the orbital period of the system. Furthermore, we find some tentative evidence for the X-ray versus optical flux anticorrelation discovered by Machin et al. using our data together with the all-sky X-ray monitoring data from RXTE/All Sky Monitor. We propose that the complex time series behaviour of 4U0614+09 is a result of drastic changes in the accretion disc geometry/structure on time-scales from hours to days. Finally, we want to draw attention to the interpretation of moderately strong peaks in the power spectra of especially accreting sources. Many of such 'periods' can probably be attributed to the presence of red noise (i.e. correlated events) in the data. Based on observations made with the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway and Sweden, in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. Uses results provided by the ASM/RXTE teams at MIT and at the RXTE SOF and GOF at NASA's GSFC.

Causal modeling of secondary science students' intentions to enroll in physics

Science.gov (United States)

Crawley, Frank E.; Black, Carolyn B.

The purpose of this study was to explore the utility of the theory of planned behavior model developed by social psychologists for understanding and predicting the behavioral intentions of secondary science students regarding enrolling in physics. In particular, the study used a three-stage causal model to investigate the links from external variables to behavioral, normative, and control beliefs; from beliefs to attitudes, subjective norm, and perceived behavioral control; and from attitudes, subjective norm, and perceived behavioral control to behavioral intentions. The causal modeling method was employed to verify the underlying causes of secondary science students' interest in enrolling physics as predicted in the theory of planned behavior. Data were collected from secondary science students (N = 264) residing in a central Texas city who were enrolled in earth science (8th grade), biology (9th grade), physical science (10th grade), or chemistry (11th grade) courses. Cause-and-effect relationships were analyzed using path analysis to test the direct effects of model variables specified in the theory of planned behavior. Results of this study indicated that students' intention to enroll in a high school physics course was determined by their attitude toward enrollment and their degree of perceived behavioral control. Attitude, subjective norm, and perceived behavioral control were, in turn, formed as a result of specific beliefs that students held about enrolling in physics. Grade level and career goals were found to be instrumental in shaping students' attitude. Immediate family members were identified as major referents in the social support system for enrolling in physics. Course and extracurricular conflicts and the fear of failure were shown to be the primary beliefs obstructing students' perception of control over physics enrollment. Specific recommendations are offered to researchers and practitioners for strengthening secondary school students

Cepheid pulsation theory and multiperiodic cepheid variables

International Nuclear Information System (INIS)

Cox, A.N.; Cox, J.P.

1975-01-01

In this review of the multiperiodic Cepheid variables, the subject matter is divided into four parts. The first discusses general causes of pulsation of Cepheids and other variable stars, and their locations on the H-R diagram. In the second section, the linear adiabatic and nonadiabatic theory calculation of radial pulsation periods and their application to the problem of masses and double-mode Cepheids are reviewed. Periodic solutions, and their stability, of the nonlinear radial pulsation equations for Cepheids and RR Lyrae stars are considered in the third section. The last section provides the latest results on nonlinear, nonperiodic, radial pulsations for Cepheids and RR Lyrae stars. (BJG)

Examining Computer Gaming Addiction in Terms of Different Variables

Science.gov (United States)

Kurt, Adile Askim; Dogan, Ezgi; Erdogmus, Yasemin Kahyaoglu; Emiroglu, Bulent Gursel

2018-01-01

The computer gaming addiction is one of the newer concepts that young generations face and can be defined as the excessive and problematic use of computer games leading to social and/or emotional problems. The purpose of this study is to analyse through variables the computer gaming addiction levels of secondary school students. The research was…

The periodicity of Plasmodium vivax and Plasmodium falciparum in Venezuela.

Science.gov (United States)

Grillet, María-Eugenia; El Souki, Mayida; Laguna, Francisco; León, José Rafael

2014-01-01

We investigated the periodicity of Plasmodium vivax and P. falciparum incidence in time-series of malaria data (1990-2010) from three endemic regions in Venezuela. In particular, we determined whether disease epidemics were related to local climate variability and regional climate anomalies such as the El Niño Southern Oscillation (ENSO). Malaria periodicity was found to exhibit unique features in each studied region. Significant multi-annual cycles of 2- to about 6-year periods were identified. The inter-annual variability of malaria cases was coherent with that of SSTs (ENSO), mainly at temporal scales within the 3-6 year periods. Additionally, malaria cases were intensified approximately 1 year after an El Niño event, a pattern that highlights the role of climate inter-annual variability in the epidemic patterns. Rainfall mediated the effect of ENSO on malaria locally. Particularly, rains from the last phase of the season had a critical role in the temporal dynamics of Plasmodium. The malaria-climate relationship was complex and transient, varying in strength with the region and species. By identifying temporal cycles of malaria we have made a first step in predicting high-risk years in Venezuela. Our findings emphasize the importance of analyzing high-resolution spatial-temporal data to better understand malaria transmission dynamics. Copyright © 2013 Elsevier B.V. All rights reserved.

ANALISIS BEBERAPA FAKTOR YANG MEMPENGARUHI HOLDING PERIOD SAHAM BIASA PADA PERUSAHAAN GO PUBLIC YANG TERCATAT DALAM INDEX LQ45

Directory of Open Access Journals (Sweden)

Vinus - Maulina

2012-05-01

Full Text Available ABSTRACT   There are many factors influencing the decision making of investors in holding their possession on security especially common stock. Monetary crisis condition has proved to be able to influence the investors’ attitude in Jakarta Stock Market in investing their capital especially about the long/short of holding a security. This study is conducted based on the differentiation of conclusion/result of study from previous studies about decision to hold security in the long/short term. The aim of this study is to analyze variables influencing holding period of common stock on public firm listed in LQ 45 Index, that are firms generally have good performance assessed based on both market performance and firm fundamental, then analyzing the dominance influencing variable. This study is conducted in Jakarta Stock Exchange with population of stocks listed in LQ 45 index in period of 2000 – 2001 with the total of 64 firms. The Sample Taking Method is purposive sampling with the criteria that the firms at least listed twice in LQ45 index on the study period. The analysis method used to analyze independent variables: spread, market value, variance return, and dividend pay out ratio and dependent variable: holding period is two stage least squares multiple regression model,  since there is possibility that the correlation of bid-ask spread from the current period and bid-ask spread and holding period from the previous period for every stock take place simultaneously. Results of the study showed that, partially, bid-ask spread variable that constitutes the different value between the highest price provided paid by buyer with the lowest price offered by seller has significance positive correlation on holding period of common stock and there is inverse correlation/significance negative between variance return variable that reflect the risk rate from stock effected by fluctuation of stock price and holding period of common stock. While

Usefulness of ultrasonographic evaluation in primary and secondary hyperparathyroidism

International Nuclear Information System (INIS)

Jeon, Tae Joo; Kim, Eun Kyung; Lee, Jong Doo; Park, Jung Soo; Lee, Jong Tae; Yoo, Hyung Sik

1999-01-01

To evaluate the accuracy and ultrasonographic findings of primary and secondary hyperparathyroidism (HPT) and correlate them with pathologic results. We reviewed 31 cases of surgically confirmed primary (n=22) and secondary (n=9) hyperparathyroidism. We used 10 or 7.5 MHz linear transducer and reviewed the location, contour, size and echogenicity of lesions. Then we evaluated the detection rate of parathyroid lesions based on surgical result and compared the result of 99m Tc-sestamibi scan (15 cases). Location of primary HPT was left lower in 9, left upper in 5, right lower in 4, right upper in 3, left midportion in 1 and superior mediastinum in 1. Lesions showed variable echogenicity-mild low echo (2), moderate low echo (10), severe low echo (2), isoecho (4) and heterogeneous echo pattern (1). All the lesions except 5 were well defined and 3 lesions had echogenic rim. Posterior enhancement and lateral shadowing were noted in 3 and 4 lesions, respectively. Nineteen of 23 primary lesions were detected by ultrasonography (82.6%) and well correlated with sestamibi scan. In case of secondary HPT, most were well defined low echoic nodular lesions, and we could detect 6 of 9 patients (67%) and 15 of 36 lesions (41.7%). Only 6 of 24 secondary lesion were detected by sestamibi scan (25%). The detection rate of ultrasonography in primary HPT was fairly good and well correlated with the result of the 99m Tc-sestamibi scan, but both diagnostic modalities were not promising in secondary HPT.

How teaching practices are connected to student intention to enrol in upper secondary school physics courses

Science.gov (United States)

Juuti, Kalle; Lavonen, Jari

2016-05-01

Background: In developed countries, it is challenging for teachers to select pedagogical practices that encourage students to enrol in science and technology courses in upper secondary school. Purpose: Aiming to understand the enrolment dynamics, this study analyses sample-based data from Finland's National Assessment in Science to determine whether pedagogical approaches influence student intention to enrol in upper secondary school physics courses. Sample: This study examined a clustered sample of 2949 Finnish students in the final year of comprehensive school (15-16 years old). Methods: Through explorative factor analysis, we extracted several variables that were expected to influence student intention to enrol in physics courses. We applied partial correlation to determine the underlying interdependencies of the variables. Results: The analysis revealed that the main predictor of enrolment in upper secondary school physics courses is whether students feel that physics is important. Although statistically significant, partial correlations between variables were rather small. However, the analysis of partial correlations revealed that pedagogical practices influence inquiry and attitudinal factors. Pedagogical practices that emphasise science experimentation and the social construction of knowledge had the strongest influence. Conclusions: The research implies that to increase student enrolment in physics courses, the way students interpret the subject's importance needs to be addressed, which can be done by the pedagogical practices of discussion, teacher demonstrations, and practical work.

Genetic variability, trait association and path analysis of yield and yield components in mungbean (vigna radiata (L.) wilczek)

International Nuclear Information System (INIS)

Tabasum, A.; Saleem, M.; Aziz, I.

2010-01-01

Genetic variability, heritability along with genetic advance of traits, their association and direct and indirect effects on yield are essential for crop improvement. Ten mungbean genotypes were studied to assess variability and degree to which various plant traits associate with seed yield. Primary and secondary branches, pods per cluster and pod length showed lesser variability while clusters per plant, 100 seed weight and harvest index exhibited intermediate range of variability. Sufficient genetic variability was observed for plant height, pods per plant, total plant weight and seed yield. Moderate to high heritability estimates were found for all traits. Primary and secondary branches per plant, pod length and 100-seed weight exhibited negative and non significant genotypic and phenotypic correlations with seed yield. Plant height showed positive non-significant and significant genotypic and phenotypic correlation. Pods per cluster correlated significantly negative with seed yield. Clusters per plant, pods per plant, total plant weight and harvest index showed positive significant genotypic and phenotypic correlations with seed yield. Positive direct effects were exerted through secondary branches, pods per plant, pod length, 100 seed weight, total plant weight and harvest index while primary branches, plant height, clusters per plant and pods per cluster had negative direct effects. The present findings could be useful for establishing selection criteria for high seed yield in the mungbean breeding. (author)

Working Memory and Fluid Intelligence: Capacity, Attention Control, and Secondary Memory Retrieval

Science.gov (United States)

Unsworth, Nash; Fukuda, Keisuke; Awh, Edward; Vogel, Edward K.

2015-01-01

Several theories have been put forth to explain the relation between working memory (WM) and gF. Unfortunately, no single factor has been shown to fully account for the relation between these two important constructs. In the current study we tested whether multiple factors (capacity, attention control, and secondary memory) would collectively account for the relation. A large number of participants performed multiple measures of each construct and latent variable analyses were used to examine the data. The results demonstrated that capacity, attention control, and secondary memory were uniquely related to WM storage, WM processing, and gF. Importantly, the three factors completely accounted for the relation between WM (both processing and storage) and gF. Thus, although storage and processing make independent contributions to gF, both of these contributions are accounted for by variation in capacity, attention control and secondary memory. These results are consistent with the multifaceted view of WM, suggesting that individual differences in capacity, attention control, and secondary memory jointly account for individual differences in WM and its relation with gF. PMID:24531497

Email communication at the medical primary-secondary care interface: a qualitative exploration.

Science.gov (United States)

Sampson, Rod; Barbour, Rosaline; Wilson, Philip

2016-07-01

There is little published research into the influence of email communication between primary and secondary care clinicians on patient care. To explore the use of email communication between clinicians across the primary- secondary care interface, and how this may relate to patient care. A qualitative study involving primary and secondary care services in the NHS Highland Health Board area, Scotland. Ten GPs and 12 hospital consultants were purposively sampled to reflect diversity. Eligible clinicians were invited to take part in a semi-structured interview. Data were analysed using a thematic analysis approach. Key themes that emerged for clinicians included general perceptions of email; using email in practice (managing workload, impact on patient journeys, and 'quick answers'); system issues (variability and governance); relational aspects; and email skills. Email communication between primary and secondary care clinicians generally has a positive impact on patient access to specialist expertise. Governance issues around the use of clinical email need to be defined. There may currently be a two-tier health service for those patients (and their GPs) requiring 'quick answers'. © British Journal of General Practice 2016.

New Variable Stars in the KP2001 Catalog from the Data Base of the Northern Sky Variability Survey

Science.gov (United States)

Petrosyan, G. V.

2018-03-01

The optical variability of stars in the KP2001 catalog is studied. Monitor data from the automatic Northern Sky Variability Survey (NSVS) are used for this purpose. Of the 257 objects that were studied, 5 are Mira Ceti variables (mirids), 33 are semiregular (SR), and 108 are irregular variables (Ir). The light curves of the other objects show no noticeable signs of variability. For the first time, 11 stars are assigned to the semiregular and 105 stars to the irregular variables. Of the irregular variables, the light curves of two, No. 8 and No. 194, are distinct and are similar to the curves for eclipsing variables. The periods and amplitudes of the mirids and semiregular variables are determined using the "VStar" program package from AAVSO. The absolute stellar magnitudes M K and distances are also estimated, along with the mass loss for the mirids. The behavior of stars from KP2001 in 2MASS and WISE color diagrams is examined.

Period variation studies of six contact binaries in M4

Science.gov (United States)

Rukmini, Jagirdar; Shanti Priya, Devarapalli

2018-04-01

We present the first period study of six contact binaries in the closest globular cluster M4 the data collected from June 1995‑June 2009 and Oct 2012‑Sept 2013. New times of minima are determined for all the six variables and eclipse timing (O-C) diagrams along with the quadratic fit are presented. For all the variables, the study of (O-C) variations reveals changes in the periods. In addition, the fundamental parameters for four of the contact binaries obtained using the Wilson-Devinney code (v2003) are presented. Planned observations of these binaries using the 3.6-m Devasthal Optical Telescope (DOT) and the 4-m International Liquid Mirror Telescope (ILMT) operated by the Aryabhatta Research Institute of Observational Sciences (ARIES; Nainital) can throw light on their evolutionary status from long term period variation studies.

Dual-component model of respiratory motion based on the periodic autoregressive moving average (periodic ARMA) method

International Nuclear Information System (INIS)

McCall, K C; Jeraj, R

2007-01-01

A new approach to the problem of modelling and predicting respiration motion has been implemented. This is a dual-component model, which describes the respiration motion as a non-periodic time series superimposed onto a periodic waveform. A periodic autoregressive moving average algorithm has been used to define a mathematical model of the periodic and non-periodic components of the respiration motion. The periodic components of the motion were found by projecting multiple inhale-exhale cycles onto a common subspace. The component of the respiration signal that is left after removing this periodicity is a partially autocorrelated time series and was modelled as an autoregressive moving average (ARMA) process. The accuracy of the periodic ARMA model with respect to fluctuation in amplitude and variation in length of cycles has been assessed. A respiration phantom was developed to simulate the inter-cycle variations seen in free-breathing and coached respiration patterns. At ±14% variability in cycle length and maximum amplitude of motion, the prediction errors were 4.8% of the total motion extent for a 0.5 s ahead prediction, and 9.4% at 1.0 s lag. The prediction errors increased to 11.6% at 0.5 s and 21.6% at 1.0 s when the respiration pattern had ±34% variations in both these parameters. Our results have shown that the accuracy of the periodic ARMA model is more strongly dependent on the variations in cycle length than the amplitude of the respiration cycles

Muslim Youth Experiences in Quebec Secondary Schools: Race, Racialization, and the 'Dangerous Muslim Man'

Directory of Open Access Journals (Sweden)

Naved Bakali

2016-10-01

Full Text Available This article examines the experiences of Muslim men who had attended the secondary schools in Quebec in the post-9/11 context. Employing a critical ethnographic approach stemming from institutional ethnography, this study presents biases/racism these men had experienced in their secondary schools in the aftermath of the 9/11 terror attacks and throughout the period of the War on Terror, and the possible causes for this treatment.

Reliability analysis of structures under periodic proof tests in service

Science.gov (United States)

Yang, J.-N.

1976-01-01

A reliability analysis of structures subjected to random service loads and periodic proof tests treats gust loads and maneuver loads as random processes. Crack initiation, crack propagation, and strength degradation are treated as the fatigue process. The time to fatigue crack initiation and ultimate strength are random variables. Residual strength decreases during crack propagation, so that failure rate increases with time. When a structure fails under periodic proof testing, a new structure is built and proof-tested. The probability of structural failure in service is derived from treatment of all the random variables, strength degradations, service loads, proof tests, and the renewal of failed structures. Some numerical examples are worked out.

How variable is the number of triggered aftershocks?

Science.gov (United States)

Marsan, D.; Helmstetter, A.

2017-07-01

Aftershock activity depends at first order on the main shock magnitude but also shows important fluctuations between shocks of equal magnitude. We here investigate these fluctuations, by quantifying them and by relating them to the main shock stress drop and other variables, for southern California earthquakes. A method is proposed in order to only count directly triggered aftershocks, rather than secondary aftershocks (i.e., triggered by previous aftershocks), and to only quantify fluctuations going beyond the natural Poisson variability. Testing of the method subjected to various model errors allows to quantify its robustness. It is found that these fluctuations follow a distribution that is well fitted by a lognormal distribution, with a coefficient of variation of about 1.0 to 1.1. A simple model is proposed to relate this observed dependence to main shock stress drop variability.

Origin of very-short orbital-period binary systems

International Nuclear Information System (INIS)

Miyaji, S.

1983-01-01

Recent observations of four close binaries have established that there is a group of very-short orbital-period (VSOP) binaries whose orbital periods are less than 60 minutes. The VSOP binaries consist of both X-ray close binaries and cataclysmic variables. Their orbital periods are too short to have a main-sequence companion. However, four binaries, none of which belongs to any globular cluster, are too abundant to be explained by the capturing mechanism of a white dwarf. Therefore it seemed to be worthwhile to present an evolutionary scenario from an original binary system which can be applied for all VSOP binaries. (Auth.)

Exploring Levels of Job Satisfaction among Teachers in Public Secondary Schools in Tanzania

Science.gov (United States)

Msuya, Ombeni William

2016-01-01

A case study on the role of extrinsic factors (hygiene factors) and socio-demographic factors in determining job satisfaction among teachers in public secondary schools in Tanzania was undertaken. Biographical variables pertaining to teachers' age, sex, marital status and work experience were investigated to determine whether they had any…

Shroud cutting techniques and collection systems for secondary radioactivity release

International Nuclear Information System (INIS)

Yokoi, H.; Watanabe, A.; Uetake, N.; Shimura, T.; Omote, T.; Adachi, H.; Murakami, S.; Kobayashi, H.; Gotoh, M.

2001-01-01

Replacement of in-core shroud has been conducted as part of the preventive maintenance program in Tsuruga-1. The EDM (electric discharged machining) and plasma cutting methods were applied to in-core shroud cutting and secondary cutting in the DSP (dryer/separator pool), respectively. The cutting systems were improved in order to decrease radioactive secondary products. 1) Fundamental EDM cutting tests: fundamental EDM cutting tests were carried out in order to study secondary products. It could be presumed that volatile Co-carbonyl compound was generated by using a carbon electrode. The Ag/W electrode was effective as EDM electrode for in-core shroud cutting to prevent generation of Co-carbonyl compound and to decrease the total amount of secondary products. 2) In-core shroud cutting in RPV (reactor pressure vessel): EDM cutting system with the Ag/W electrode and collection system could keep a good environment during in-core shroud cutting in Tsuruga-1. Activity concentration was lower value than limitation of mask charge level, 4E-6 Bq/cm 3 , even near the water surface. 3) Secondary plasma cutting in DSP: the secondary cutting work was successful in the point of reduction of working period and radiation exposure. The amount of radiation exposure was reduced to 60% of the planned value, because of adequate decontamination of the working environment and reduction of number of torch maintenance tasks by improvements of the underwater cutting device

Influences of the alternation of wet-dry periods on the variability of chromophoric dissolved organic matter in the water level fluctuation zone of the Three Gorges Reservoir area, China.

Science.gov (United States)

Jiang, Tao; Wang, Dingyong; Wei, Shiqiang; Yan, Jinlong; Liang, Jian; Chen, Xueshuang; Liu, Jiang; Wang, Qilei; Lu, Song; Gao, Jie; Li, Lulu; Guo, Nian; Zhao, Zheng

2018-04-26

Dissolved organic matter (DOM) is a crucial driver of various biogeochemical processes in aquatic systems. Thus, many lakes and streams have been investigated in the past several decades. However, fewer studies have sought to understand the changes in DOM characteristics in the waters of the Three Gorges Reservoir (TGR) areas, which are the largest artificial reservoir areas in the world. Thus, a field investigation of dissolved organic carbon (DOC) concentrations and of chromophoric dissolved organic matter (CDOM) properties was conducted from 2013 to 2015 to track the spatial-temporal variability of DOM properties in the TGR areas. The results showed that the alternations of wet and dry periods due to hydrological management have a substantial effect on the quantity and quality of aquatic DOM in TGR areas. Increases in DOC concentrations in the wet period show an apparent "dilution effect" that decreases CDOM compounds with relatively lower aromaticity (i.e., SUVA 254 ) and molecular weight (i.e., S R ). In contrast to the obvious temporal variations of DOM, significant spatial variability was not observed in this study. Additionally, DOM showed more terrigenous characteristics in the dry period but weak terrigenous characteristics in the wet period. Furthermore, the positive correlation between SUVA 254 and CDOM suggests that the aromatic component controls the CDOM dynamics in TGR areas. The first attempt to investigate the DOM dynamics in TGR areas since the Three Gorges Dam was conducted in 2012, and the unique patterns of spatial-temporal variations in DOM that are highlighted in this study might provide a new insight for understanding the role of DOM in the fates of contaminants and may help in the further management of flow loads and water quality in the TGR area. Copyright © 2018 Elsevier B.V. All rights reserved.

Portal hydatid with secondary cavernomatosis.

Science.gov (United States)

Rodríguez Sanz, Mª Belén; Roldán Cuena, Mª Del Mar; Blanco Álvarez, Carlos Alberto; Sánchez Jiménez, Raúl

2017-03-01

The hydatid cyst is a parasitic infection included within the category of zoonoses, in which there exists a direct or indirect relation with animals, particularly with dogs. We report a clinical case of a patient who has undergone surgery of hydatid cyst in the right hepatic lobe. Seven years later the patient presents hydatid cyst in portal vein with secondary cavernomatosis, which is a rare complication. There are few cases described in the literature. The symtomatology presented by hydatid cyst is variable and the diagnosis is made by ultrasonography, TC and/or RNM. The treatment of choice is the surgical removal of the cyst, prior to surgery Albendazol must be administered for 1-2 weeks and be maintained for 4 more weeks after surgery.

Primary and secondary cases in Escherichia coli O157 outbreaks: a statistical analysis.

LENUS (Irish Health Repository)

Snedeker, Kate G

2009-01-01

BACKGROUND: Within outbreaks of Escherichia coli O157 (E. coli O157), at least 10-15% of cases are thought to have been acquired by secondary transmission. However, there has been little systematic quantification or characterisation of secondary outbreak cases worldwide. The aim of this study was to characterise secondary outbreak cases, estimate the overall proportion of outbreak cases that were the result of secondary transmission and to analyse the relationships between primary and secondary outbreak cases by mode of transmission, country and median age. METHODS: Published data was obtained from 90 confirmed Escherichia coli O157 outbreaks in Great Britain, Ireland, Scandinavia, Canada, the United States and Japan, and the outbreaks were described in terms of modes of primary and secondary transmission, country, case numbers and median case age. Outbreaks were tested for statistically significant differences in the number of ill, confirmed, primary and secondary cases (analysis of variance and Kruskal-Wallis) and in the rate of secondary cases between these variables (Generalised Linear Models). RESULTS: The outbreaks had a median of 13.5 confirmed cases, and mean proportion of 0.195 secondary cases. There were statistically significant differences in the numbers of ill, confirmed, primary and secondary cases between modes of primary transmission (p < 0.021), and in primary and secondary cases between median age categories (p < 0.039) and modes of secondary transmission (p < 0.001).Secondary case rates differed statistically significantly between modes of secondary and primary transmission and median age categories (all p < 0.001), but not between countries (p = 0.23). Statistically significantly higher rates of secondary transmission were found in outbreaks with a median age <6 years and those with secondary transmission via person to person spread in nurseries. No statistically significant interactions were found between country, mode of transmission and age

Predictors for secondary therapy after surgical resection of nonfunctioning pituitary adenomas.

Science.gov (United States)

Ratnasingam, Jeyakantha; Lenders, Nele; Ong, Benjamin; Boros, Samuel; Russell, Anthony W; Inder, Warrick J; Ho, Ken K Y

2017-12-01

Factors determining recurrence of nonfunctioning pituitary adenomas (NFAs) that require further therapy are unclear as are postoperative follow-up imaging guidelines. We aimed to identify predictors for secondary therapy after surgical resection of NFAs and use this knowledge to inform postoperative management. A single-centre retrospective study of surgically resected NFAs in 108 patients followed for up to 15 years. Serial tumour images were analysed for size, location and growth rate (GR) and tissue analysed for hormone cell type and proliferation indices with secondary treatment as outcome measure. Twenty-four of 66 (36%) patients harbouring a postoperative remnant required secondary treatment, all occurring within 10 years. No secondary treatment was required in any of 42 patients with complete tumour resection. Age, gender, remnant volume and tumour histology were not different between patients requiring and not requiring secondary therapy. Remnant GRs in those requiring secondary therapy were more than 10-fold higher (Prisk for secondary therapy. Tumour GR in the first three postoperative years correlated significantly (r 2 =.6, P<.01) with GR during the period of follow-up. In surgically resected NFAs further treatment is dependent on the presence of residual tumour, growth rate and location but not tumour histology. Postoperative growth rate of NFAs in the first 3 years of imaging can be used to tailor long-term follow-up to optimize use of health resources. © 2017 John Wiley & Sons Ltd.

Human Capital Variables and Economic Growth in Nigeria: An Interactive Effect

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Adenike Mosunmola Osoba

2017-05-01

Full Text Available Various studies have focused on the relationship between human capital and economic growth all over the world. However, there is still a missing gap on the joint influence of human capital investment components on economic growth particularly in Nigeria. This study therefore examines the interactive effects of the relationship between human capital investment components and economic growth in Nigeria for the period of 1986 – 2014. The study employed secondary annual data on education expenditure, health expenditure, real gross domestic product and gross capital formation obtained from the Central Bank Statistical bulletin, 2014. The data were analyzed using Fully Modified Ordinary Least Squares (FMOLS technique. The results of the study showed that there was positive and significant relationship between the interactive effects of human capital components and growth in Nigeria. The study concluded that the interactive effect of the human capital variables was also in conformity with the theoretical proposition that increase in human capital will enhance growth as stipulated in the modified Solow growth model by Mankiw, Romer & Weil (1992.

Analytic functions of several complex variables

CERN Document Server

Gunning, Robert C

2009-01-01

The theory of analytic functions of several complex variables enjoyed a period of remarkable development in the middle part of the twentieth century. After initial successes by Poincaré and others in the late 19th and early 20th centuries, the theory encountered obstacles that prevented it from growing quickly into an analogue of the theory for functions of one complex variable. Beginning in the 1930s, initially through the work of Oka, then H. Cartan, and continuing with the work of Grauert, Remmert, and others, new tools were introduced into the theory of several complex variables that resol

Behavior of secondary particles in particulate matter collected at eastern Kanagawa

International Nuclear Information System (INIS)

Nishida, Tomohiro; Kikawada, Yoshikazu; Oi, Takao; Honda, Teruyuki

2008-01-01

The suspended particulate matters collected in 100 periods from 2002/10/28 to 2004/10/29 were separated into the water soluble and insoluble components and their main components were analyzed. The characteristics of atmosphere in the east part of Kagawa prefecture and of the secondary particulates were presumed. Therefore, it was considered that in the samples other than Mn the origins of water soluble and insoluble components are different each other from their behavior. The water-soluble part may be mostly ammonium salt (secondary particulate) from the measurement of NH 4 + . Furthermore, it became clear that the evolution of secondary particulate varies largely with season. Then, the variation with season was presumed by the main component analysis using the statistical software, SPSS adding to the correlation coefficient. This method has proved to be effective. (M.H.)

L2 Motivation, Anxiety and Self-Efficacy: The Interrelationship of Individual Variables in the Secondary School Context

Science.gov (United States)

Piniel, Katalin; Csizér, Kata

2013-01-01

Our study describes the relationship of second language learning motivation, self-efficacy, and anxiety; that is, how motivation, cognition, and affect might interact during the process of second language learning. Questionnaire data were collected from 236 Hungarian students studying at various secondary schools. Structural equation modeling was…

The first orbital parameters and period variation of the short-period eclipsing binary AQ Boo

Science.gov (United States)

Wang, Shuai; Zhang, Liyun; Pi, Qingfeng; Han, Xianming L.; Zhang, Xiliang; Lu, Hongpeng; Wang, Daimei; Li, TongAn

2016-10-01

We obtained the first VRI CCD light curves of the short-period contact eclipsing binary AQ Boo, which was observed on March 22 and April 19 in 2014 at Xinglong station of National Astronomical Observatories, and on January 20, 21 and February 28 in 2015 at Kunming station of Yunnan Observatories of Chinese Academy of Sciences, China. Using our six newly obtained minima and the minima that other authors obtained previously, we revised the ephemeris of AQ Boo. By fitting the O-C (observed minus calculated) values of the minima, the orbital period of AQ Boo shows a decreasing tendency P˙ = - 1.47(0.17) ×10-7 days/year. We interpret the phenomenon by mass transfer from the secondary (more massive) component to the primary (less massive) one. By using the updated Wilson & Devinney program, we also derived the photometric orbital parameters of AQ Boo for the first time. We conclude that AQ Boo is a near contact binary with a low contact factor of 14.43%, and will become an over-contact system as the mass transfer continues.

Secondary recrystallisation in 20 w/o Cr-25 w/o Ni-Nb stabilised stainless steel

International Nuclear Information System (INIS)

Healey, T.; Brown, A.F.; Speight, M.V.

1976-11-01

The fuel cladding material for the Commercial Advanced Gas Reactor is a fine grain 20 w/o Cr-25 w/o Ni niobium stabilised stainless steel. The grain structure stability of this alloy has been investigated as a function of carbon content over the temperature range 930 - 990 0 C. It is demonstrated that the primary grain structure is susceptible to abnormal growth due to secondary recrystallisation of the initial fine grain structure after a composition and temperature dependent incubation period. The magnitude of the incubation period is analysed on the basis that secondary recrystallisation commences when randomly dispersed niobium carbide particles have coarsened to a critical size. The validity of the analysis is tested by comparing the predictions with experimental observation. The model is subsequently used to evaluate the incubation period for conditions of temperature, composition and microstructure which differ from those defined in the experimental studies. (author)

Variable stars in the field of open cluster NGC 2126

International Nuclear Information System (INIS)

Liu Shunfang; Wu Zhenyu; Zhang Xiaobin; Wu Jianghua; Ma Jun; Jiang Zhaoji; Chen Jiansheng; Zhou Xu

2009-01-01

We report the results of a time-series CCD photometric survey of variable stars in the field of open cluster NGC 2126. In about a one square degree field covering the cluster, a total of 21 variable candidates are detected during this survey, of which 16 are newly found. The periods, classifications and spectral types of 14 newly discovered variables are discussed, which consist of six eclipsing binary systems, three pulsating variable stars, three long period variables, one RS CVn star, and one W UMa or δ Scuti star. In addition, there are two variable candidates, the properties of which cannot be determined. By a method based on fitting observed spectral energy distributions of stars with theoretical ones, the membership probabilities and the fundamental parameters of this cluster are determined. As a result, five variables are probably members of NGC 2126. The fundamental parameters of this cluster are determined as: metallicity to be 0.008 Z o-dot , age log(t) = 8.95, distance modulus (m - M) 0 = 10.34 and reddening value E (B - V) = 0.55 mag.

Pulmonary arterial hypertension secondary to chronic thromboemboli

International Nuclear Information System (INIS)

Crysikopoulos, H.; Forrest, J.V.; Olson, L.K.; Roberts, A.C.

1989-01-01

The authors report their experience in 150 patients with pulmonary arterial hypertension secondary to chronic pulmonary embolism (CPE). Plain film findings are variable, commonly nonspecific. Occasionally nonuniformity of pulmonary perfusion or truncation of central pulmonary arteries suggest CPE. Multiple, large, unmatched perfusion defects are the most common scintigraphic observations. CT can exclude conditions mimicking CPE, particularly fibrosing mediastinitis. Pulmonary arteriography depicts the location and distribution of emboli. CPE is becoming an increasingly important entity to recognize because of available surgical treatment. Thromboendarterectomy may improve functional status and survival. The diagnosis should be considered in any patient with pulmonary arterial hypertension

Periodicity of the stable isotopes

CERN Document Server

Boeyens, J C A

2003-01-01

It is demonstrated that all stable (non-radioactive) isotopes are formally interrelated as the products of systematically adding alpha particles to four elementary units. The region of stability against radioactive decay is shown to obey a general trend based on number theory and contains the periodic law of the elements as a special case. This general law restricts the number of what may be considered as natural elements to 100 and is based on a proton:neutron ratio that matches the golden ratio, characteristic of biological and crystal growth structures. Different forms of the periodic table inferred at other proton:neutron ratios indicate that the electronic configuration of atoms is variable and may be a function of environmental pressure. Cosmic consequences of this postulate are examined. (author)

Preliminary studies on a variable energy positron annihilation lifetime spectroscopy system

International Nuclear Information System (INIS)

Kwan, P.Y.; Cheung, C.K.; Beling, C.D.; Fung, S.

2006-01-01

There are many advantages in being able to perform positron annihilation lifetime spectroscopy (PALS) using a variable energy positron beam, the most obvious being the easy identification of different defect types at different depths. The difficulty in conducting variable energy (VE) PALS studies lies in the fact that a 'start' signal is required to signal the entry of the positron into the target. Two methods have been used to overcome this problem, namely the bunching technique, which employs radio frequency (RF) cavities and choppers, and secondly the use of secondary electrons emitted from the target. The latter technique is in terms of experimental complexity much simpler, but has in the past suffered from poor time resolution (typically ∼500 ps). In this work, we present a series of computer simulations of a design based on the secondary electron emission from thin C-foils in transmission mode which shows that significant improvements in time resolution can be made with resolutions ∼200 ps being in principle possible

Secondary intracranial meningiomas after high-dose cranial irradiation: report of five cases and review of the literature

International Nuclear Information System (INIS)

Strojan, Primoz; Popovic, Mara; Jereb, Berta

2000-01-01

Purpose: To review cases of secondary intracranial meningiomas following high-dose cranial irradiation (≥ 10 Gy) identified in Slovenia between 1968 and 1998, to determine their histological profile and to review the literature on this topic. Methods and Materials: Personal files of patients treated for secondary intracranial meningioma during a 31-year period were reviewed. In cases which met the criteria for radiation-induced tumors, steroid hormone receptor and Ki-67 status were analyzed. For the literature review, computerized database systems and reference lists from respective publications were used. Results: Five patients (2 females, 3 males), 3-11 years old at the time of cranial irradiation, developed secondary meningioma after a latency period of 9.5-31.5 years. Three patients had multiple tumors and 2 developed recurrent disease. Of 9 histologically examined tumors, 5 were graded as benign and 4 as atypical meningiomas, with Ki-67 proliferative index 3.2 ± 3.6 and 10 ± 6, respectively. The ratio between positive and negative meningiomas regarding immunostaining for progesterone and estrogen receptors was eight-to-one and six-to-three, respectively. Cumulative actuarial risk of secondary meningioma in a cohort of 445 children 16 years or younger treated with high-dose cranial irradiation between 1968 and 1990 in Slovenia at 10, 20, and 25 years was 0.53%, 1.2%, and 8.18%, respectively. Out of 126 cases of radiation-induced meningiomas reported, 57% were females and 43% were males, with mean age at presentation 33 ± 17.3 years. The majority (68%) of patients was irradiated during childhood. The latency period was significantly shorter in those who aged 5 years or less at the time of cranial irradiation (p = 0.04), and in those with atypical/anaplastic tumor (p = 0.01). Correlation between radiation dose and latency period could not be found. Conclusion: Secondary meningiomas following high-dose cranial irradiation are characterized by younger age at

Variability in the Initial Costs of Care and One-Year Outcomes of Observation Services

Directory of Open Access Journals (Sweden)

Abbass, Ibrahim

2015-05-01

Full Text Available Introduction: The use of observation units (OUs following emergency departments (ED visits as a model of care has increased exponentially in the last decade. About one-third of U.S. hospitals now have OUs within their facilities. While their use is associated with lower costs and comparable level of care compared to inpatient units, there is a wide variation in OUs characteristics and operational procedures. The objective of this research was to explore the variability in the initial costs of care of placing patients with non-specific chest pain in observation units (OUs and the one-year outcomes. Methods: The author retrospectively investigated medical insurance claims of 22,962 privately insured patients (2009-2011 admitted to 41 OUs. Outcomes included the one-year chest pain/cardiovascular related costs and primary and secondary outcomes. Primary outcomes included myocardial infarction, congestive heart failure, stroke or cardiac arrest, while secondary outcomes included revascularization procedures, ED revisits for angina pectoris or chest pain and hospitalization due to cardiovascular diseases. The author aggregated the adjusted costs and prevalence rates of outcomes for patients over OUs, and computed the weighted coefficients of variation (WCV to compare variations across OUs. Results: There was minimal variability in the initial costs of care (WCV=2.2%, while the author noticed greater variability in the outcomes. Greater variability were associated with the adjusted cardiovascular-related costs of medical services (WCV=17.6% followed by the adjusted prevalence odds ratio of patients experiencing primary outcomes (WCV=16.3% and secondary outcomes (WCV=10%. Conclusion: Higher variability in the outcomes suggests the need for more standardization of the observation services for chest pain patients. [West J Emerg Med. 2015;16(3:395–400.

Inspection of secondary cooling system piping of JMTR

International Nuclear Information System (INIS)

Hanawa, Yoshio; Izumo, Hironobu; Fukasaku, Akitomi; Nagao, Yoshiharu; Kawamura, Hiroshi

2008-06-01

Piping condition was inspected form the view point of long term utilization before the renewal work of the secondary cooling system in the JMTR on FY 2008. As the result, it was confirmed that cracks, swellings and exfoliations in inner lining of the piping could be observed, and corrosion, which was reached by piping ingot, or decrease of piping thickness could hardly be observed. It was therefore confirmed that the strength or the functionality of the piping had been maintained by usual operation and maintenance. Repair of inner lining of the piping during the refurbishment of the JMTR is necessary to long term utilization of the secondary cooling system after restart of the JMTR from the view point of preventive maintenance. In addition, a periodic inspection of inner lining condition is necessary after repair of the piping. (author)

Two methods for studying the X-ray variability

NARCIS (Netherlands)

Yan, Shu-Ping; Ji, Li; Méndez, Mariano; Wang, Na; Liu, Siming; Li, Xiang-Dong

2016-01-01

The X-ray aperiodic variability and quasi-periodic oscillation (QPO) are the important tools to study the structure of the accretion flow of X-ray binaries. However, the origin of the complex X-ray variability from X-ray binaries remains yet unsolved. We proposed two methods for studying the X-ray

[Cryopyrine-associated periodic syndrome: CAPS seen from adulthood].

Science.gov (United States)

Koné-Paut, I

2015-04-01

Cryopyrin-associated periodic syndrome is a rare hereditary periodic fever syndrome for which, the genetic mechanism, mutation in the NLRP3 gene, has allowed to gather 3 clinical phenotypes (familial cold urticaria [FCAS], Muckle-Wells syndrome [MWS], and chronic infantile neurological cutaneous and articular syndrome [CINCA]) initially described independently, and to discover the NLRP3 inflammasome, a key receptor of the innate immunity, which regulates the interleukine-1β secretion into the mononuclear cells. The clinical manifestation of CAPS : urticaria-like skin rash, eyes redness, myalgia and sensory deafness are not specific, if considered separately, and that often leads to a wandering diagnosis through a complex medical journey including various specialists. The diagnostic delay is deleterious to patients compromising their quality of life and exposing them to neurosensory complications and renal failure by secondary amyloidosis. The paediatric onset of disease, the family history, the trigger of symptoms by the cold, and the recognition of the skin rash as neutrophilic are important clues before diagnostic confirmation by genetic testing. Interleukine-1 blockade is the only effective treatment of CAPS symptoms which often may stabilize (rarely regression) the sensory involvement and in some cases may allow the regression of secondary amyloidosis. Copyright © 2014 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Work stress and work-based learning in secondary education : testing the Karasek model

NARCIS (Netherlands)

Kwakman, Kitty

2001-01-01

In this study the Job Demand-Control model was used to study the quality of working life of Dutch secondary teachers. The Job Demand-Control model of Karasek is a theoretical model in which stress and learning are both considered as dependent variables which are influenced by three different task

Work stress and work based learning in secondary education: Testing the Karasek model

NARCIS (Netherlands)

Kwakman, Kitty

1999-01-01

In this study the Job Demand-Control model was used to study the quality of working life of Dutch secondary teachers. The Job Demand-Control model of Karasek is a theoretical model in which stress and learning are both considered as dependent variables which are influenced by three different task

Predicting Homework Time Management at the Secondary School Level: A Multilevel Analysis

Science.gov (United States)

Xu, Jianzhong

2010-01-01

The purpose of this study is to test empirical models of variables posited to predict homework time management at the secondary school level. Student- and class-level predictors of homework time management were analyzed in a survey of 1895 students from 111 classes. Most of the variance in homework time management occurred at the student level,…

Process variables in organizational stress management intervention evaluation research: a systematic review

NARCIS (Netherlands)

Havermans, B.M.; Schelvis, R.M.C.; Boot, C.R.L.; Brouwers, E.P.M.; Anema, J.R.; Beek, A.J. van der

2016-01-01

Objectives This systematic review aimed to explore which process variables are used in stress management intervention (SMI) evaluation research. Methods A systematic review was conducted using seven electronic databases. Studies were included if they reported on an SMI aimed at primary or secondary

The Successful Scientific Periodicals: Contemporary Issues

Directory of Open Access Journals (Sweden)

B.V. Toshev

2014-12-01

Full Text Available The new scientific results should be published. However, the scientific result will be lost in inappropriate choice of the media in which is expected to appear. The world periodicals are developed in two levels, parts of the World System of Abstracting, Indexing and Evaluation, WSAIE. This system is just the body of the world science. The first level consists of the primary research journals. After careful inspection these journals should be accepted for covering in secondary research sources; the latter build the second level of the system. Journals, which are not presented in secondary research sources, are considered as marginal and the submission of manuscripts to such journals is not recommended. The second level of WSAIE has an elite part, an American one (Thomson Reuters, Web of Science, and an European one (Elsevier, SCOPUS. The journals of Web of Science are characterized by their impact factor, IF; the journals of SCOPUS are characterized by their im-pact rank, SJR; these journals' scientometric characteristics are entirely equal in use; no one of them should be favoured in respect to the other. However, these factors characterize the journals, not authors publishing in them; there-fore, these numbers cannot be used neither to compare different scientific areas nor in the personal evaluation of authors' scientific activity. The personal and institutional competencies for research could be estimated by properly use of some scientometric variables. The most important of them are considered. Amongst them are the index of Hirsch, h, and the factor of efficiency, e. In twenty-first century a new development of science began. The researchers should know the features of the contemporary science policy; otherwise the traps of the new time would compromise the effort of the researcher to achieve a success in his/her research activity. The status and the new developments in world science are both discussed. The transition from the 'normal

RADIO VARIABILITY IN SEYFERT NUCLEI

International Nuclear Information System (INIS)

Mundell, C. G.; Ferruit, P.; Nagar, N.; Wilson, A. S.

2009-01-01

Comparison of 8.4 GHz radio images of a sample of eleven, early-type Seyfert galaxies with previous observations reveals possible variation in the nuclear radio flux density in five of them over a seven year period. Four Seyferts (NGC 2110, NGC 3081, MCG -6-30-15, and NGC 5273) show a decline in their 8.4 GHz nuclear flux density between 1992 and 1999, while one (NGC 4117) shows an increase; the flux densities of the remaining six Seyferts (Mrk 607, NGC 1386, Mrk 620, NGC 3516, NGC 4968, and NGC 7465) have remained constant over this period. New images of MCG -5-23-16 are also presented. We find no correlation between radio variability and nuclear radio luminosity or Seyfert nuclear type, although the sample is small and dominated by type 2 Seyferts. Instead, a possible correlation between the presence of nuclear radio variability and the absence of hundred parsec-scale radio emission is seen, with four out of five marginally resolved or unresolved nuclei showing a change in nuclear flux density, while five out of six extended sources show no nuclear variability despite having unresolved nuclear sources. NGC 2110 is the only source in our sample with significant extended radio structure and strong nuclear variability (∼38% decline in nuclear flux density over seven years). The observed nuclear flux variability indicates significant changes are likely to have occurred in the structure of the nucleus on scales smaller than the VLA beam size (i.e., within the central ∼0.''1 (15 pc)), between the two epochs, possibly due to the appearance and fading of new components or shocks in the jet, consistent with previous detection of subparsec-scale nuclear structure in this Seyfert. Our results suggest that all Seyferts may exhibit variation in their nuclear radio flux density at 8.4 GHz, but that variability is more easily recognized in compact sources in which emission from the variable nucleus is not diluted by unresolved, constant flux density radio jet emission

[Treatment with the use of microcurrent lymphatic drainage physiotherapy during the postoperative period following rhinoplastic surgery].

Science.gov (United States)

Aleksanyan, T A; Kazantsev, E V

The objective of the present study was to evaluate the effectiveness of the combined treatment of the patients who had undergone either primary or secondary rhinoplastic surgery with the use of photo- and magnetic therapy in comparison with the effectiveness of phototherapy in the combination with microcurrent therapy. The patients were divided into four groups depending on the type of the surgical intervention and the mode of the combined physiotherapeutic treatment. All the patients were given combined physiotherapeutic treatment in addition to the standard pharmacotherapy starting from the second day of the postoperative period. The patients of groups 1 and 3 received phototherapy in the combination with magnetic therapy while those in groups 2 and 4 were treated by phototherapy in the combination with microcurrent lymphatic drainage physiotherapy. It was shown that the different combinations of physiotherapeutic modalities during the postoperative period following primary «closed» rhinoplasty were not different significantly in terms of effectiveness. After secondary «closed» rhinoplasty, the combination of phototherapy with the application of microcurrents looks more preferable. It is concluded that microcurrent lymphdraining physiotherapy should be regarded as the priority component of the combined physiotherapeutic treatment during the postoperative period following secondary «closed» rhinoplasty.

NPP Temelin automatic monitoring and diagnostic system of secondary side of the unit 1

International Nuclear Information System (INIS)

Heidenreich, S.; Pisl, M.; Drab, F.

1997-01-01

Two measuring and evaluating systems by SKODA PRAHA are described, designed for the Temelin nuclear power plant: a permanent secondary side diagnostic system for technology monitoring in the period of startup and operation; and the system of physical and power starting-up for monitoring during the first and repeated startup. The purposes of both systems are outlined. The scope of diagnostics covered and the functioning of the secondary side system is dealt with in some detail. (A.K.)

Seasonality of primary and secondary production in an Arctic river

Science.gov (United States)

Kendrick, M.; Huryn, A.; Deegan, L.

2011-12-01

Rivers and streams that freeze solid for 8-9 months each year provide excellent examples of the extreme seasonality of arctic habitats. The communities of organisms inhabiting these rivers must complete growth and development during summer, resulting in a rapid ramp-up and down of production over the short ice-free period. The effects of recent shifts in the timing of the spring thaw and autumn freeze-up on the duration and pattern of the period of active production are poorly understood. We are currently investigating: 1) the response of the biotic community of the Kuparuk River (Arctic Alaska) to shifts in the seasonality of the ice-free period, and 2) the community response to increases in phosphorous (P) supply anticipated as the volume of the permafrost active-layer increases in response to climate warming. Here algal production supports a 2-tier web of consumers. We tracked primary and secondary production from the spring thaw through mid-August in a reference reach and one receiving low-level P fertilization. Gross primary production/community respiration (GPP/R) ratios for both reaches were increasing through mid-July, with higher GPP/R in response to the P addition. Understanding the degree of synchrony between primary and secondary production in this Arctic river system will enhance further understanding of how shifts in seasonality affect trophic dynamics.

Challenges of Formulation of Strategic Plans in Secondary Schools in Kenya: A Case of Mombasa County and Its Environs

Science.gov (United States)

Nyagah, Agnes S. M.

2015-01-01

The study is aimed at analyzing the factors that affect formulation of strategic plans in secondary schools in Mombasa County and its environs. The study looks at various variables namely leadership, training, resources allocation and education policy frameworks as the main challenges. The paper concludes that the above variables to a large extent…

The 1430s: a cold period of extraordinary internal climate variability during the early Spörer Minimum with social and economic impacts in north-western and central Europe

Science.gov (United States)

Camenisch, Chantal; Keller, Kathrin M.; Salvisberg, Melanie; Amann, Benjamin; Bauch, Martin; Blumer, Sandro; Brázdil, Rudolf; Brönnimann, Stefan; Büntgen, Ulf; Campbell, Bruce M. S.; Fernández-Donado, Laura; Fleitmann, Dominik; Glaser, Rüdiger; González-Rouco, Fidel; Grosjean, Martin; Hoffmann, Richard C.; Huhtamaa, Heli; Joos, Fortunat; Kiss, Andrea; Kotyza, Oldřich; Lehner, Flavio; Luterbacher, Jürg; Maughan, Nicolas; Neukom, Raphael; Novy, Theresa; Pribyl, Kathleen; Raible, Christoph C.; Riemann, Dirk; Schuh, Maximilian; Slavin, Philip; Werner, Johannes P.; Wetter, Oliver

2016-12-01

Changes in climate affected human societies throughout the last millennium. While European cold periods in the 17th and 18th century have been assessed in detail, earlier cold periods received much less attention due to sparse information available. New evidence from proxy archives, historical documentary sources and climate model simulations permit us to provide an interdisciplinary, systematic assessment of an exceptionally cold period in the 15th century. Our assessment includes the role of internal, unforced climate variability and external forcing in shaping extreme climatic conditions and the impacts on and responses of the medieval society in north-western and central Europe.Climate reconstructions from a multitude of natural and anthropogenic archives indicate that the 1430s were the coldest decade in north-western and central Europe in the 15th century. This decade is characterised by cold winters and average to warm summers resulting in a strong seasonal cycle in temperature. Results from comprehensive climate models indicate consistently that these conditions occurred by chance due to the partly chaotic internal variability within the climate system. External forcing like volcanic eruptions tends to reduce simulated temperature seasonality and cannot explain the reconstructions. The strong seasonal cycle in temperature reduced food production and led to increasing food prices, a subsistence crisis and a famine in parts of Europe. Societies were not prepared to cope with failing markets and interrupted trade routes. In response to the crisis, authorities implemented numerous measures of supply policy and adaptation such as the installation of grain storage capacities to be prepared for future food production shortfalls.

Spectrum of EY Orionis at the secondary eclipse

International Nuclear Information System (INIS)

Ismailov, N.Z.

1987-01-01

The results of spectral observations of the binary system EY orions at the secondary eclipse are presented. Some peculiar properties in the linear spectrum of the star have been discovered. The spectrum of the second component is not observed. The rotational velocity of the visible component is equal to 150 ± 30 km/s. During the phases 0.52-0.58, during approximately 1 d the radial velocities deviate from the radial velocity curve. According to the character of its spectrum the system EY Orions is similar to typical Orion variables

Runoff Variability in the Scott River (SW Spitsbergen in Summer Seasons 2012–2013 in Comparison with the Period 1986–2009