bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antibacterial, antifungal and cytotoxic effects of a sea cucumberHolothuria leucospilota, from the north coast of the Persian Gulf
Authors: Mohammadizadeh Flora , Ehsanpor Maryam , Afkhami Majid , Mokhlesi Amin , Khazaali Aida , Montazeri Shohreh 
Published: February 2013

Bioactive compounds of gonad, respiration tree, cuvierian organ, and body wall of the sea cucumberHolothuria leucospilotacollected from the north coast of the Persian Gulf were extracted using ethyl acetate, methanol and water–methanol solvents. Extracts were evaluated for their antibacterial and antifungal activities againstAspergillus niger,Candida albicans,Staphylococcus aureus,Pseudomonas aeruginosaandEscherichia coli. The activity was determined using the disc diffusion test. Cytotoxic activities of the extracts were determined by brine shrimp lethality assay. Results demonstrated that theA. nigerwas shown to be the most sensitive microorganism followed byC. albicans. The inhibition zone againstA. nigerandC. albicanshad minimum inhibitory concentrations ranging from 3 to 7 μg/ml. The highest antifungal activity was found in G (water–methanol) with an inhibition zone of 50 mm againstA. nigerat 18 μg/ml extract concentration continuing with CT (methanol) with 46 mm inhibition zone againstA. nigerat 18 μg/ml extract concentration. The highest cytotoxic effect of methanol extract was found with LC50values of about 40.31 μg/ml in the gonad organ fromH. leucospilotacontinuing with the respiration tree organ with LC50values of about 72.49 μg/ml.
Megafauna of the Charlie–Gibbs Fracture Zone (northern Mid-Atlantic Ridge) based on video observations
Authors: Gebruk A.V. , Krylova E.M. 
Published: February 2013

Megafauna from the Charlie–Gibbs Fracture Zone (northern Mid-Atlantic Ridge) based on video observations from submersibles was analysed. Species composition was examined, frequency of species occurrence on the fracture wall and its base (depth range from 1740 m to 3100 m) and density of megafauna in the depression at the fracture zone bottom (4200–4500 m depth) were evaluated. At depths between 1700 and 2500 m hexactinellid sponges were most common and diverse. Deeper parts of the wall and its base were dominated by anthozoans (especially gorgonian corals) and echinoderms. A set of dominant species in the lower bathyal in the study area was different from that on the lower continental slope in the north-east Atlantic (Porcupine Seabight). An important contribution to local species richness of ‘rare’ species was demonstrated. The elpidiid holothurian, Kolga nana, occurred at high density in the abyssal depression.
The politics of immigrant policy in the 50 US states, 2005-2011
Authors: Monogan James E. 
Published: February 2013

AbstractThis article asks what shaped immigrant policy in the 50 states between 2005 and 2011. Theoretically, politicians are influenced by electoral considerations as they craft laws. Law-makers consider both current public opinion and how the electorate is likely to change, at least in the near future. Empirically, the article analyses an original dataset on immigrant-related laws enacted by the states with a Bayesian spatial conditionally autoregressive model. The analysis shows that state immigrant policy is affected primarily by legislative professionalism, electoral ideology, state wealth and change in the foreign-born population.
The second-language vocabulary trajectories of Turkish immigrant children in Norway from ages five to ten: the role of preschool talk exposure, maternal education, and co-ethnic concentration in the neighborhood
Authors: RYDLAND VESLEMØY , GRØVER VIBEKE , LAWRENCE JOSHUA 
Published: February 2013

ABSTRACTLittle research has explored how preschools can support children's second-language (L2) vocabulary development. This study keenly followed the progress of twemty-six Turkish immigrant children growing up in Norway from preschool (age five) to fifth grade (age ten). Four different measures of preschool talk exposure (amount and diversity of teacher-led group talk and amount and diversity of peer talk), as well as the demographic variables of maternal education and co-ethnic concentration in the neighborhood, were employed to predict the children's L2 vocabulary trajectories. The results of growth analyses revealed that maternal education was the only variable predicting children's vocabulary growth during the elementary years. However, teacher-led talk, peer talk, and neighborhood predicted children's L2 vocabulary skills at age five, and these differences were maintained up to age ten. This study underscores the importance of both preschool talk exposure (teacher-led talk and peer talk) and demographic factors on L2 learners' vocabulary development.
Paid Companions: A Private Care Option for Older Adults
Authors: Outcalt Linda 
Published: February 2013

RÉSUMÉLes compagnons rémunérés, fonctionnant d’une façon autonome ou par le biais des agences privées de soins à domicile, effectuent une variété de services pour les personnes âgées nanties qui peuvent se payer pour le soutien privé dans leurs maisons et dans les centres qui dispensent tels soins. Cette étude a examiné le travail accompli par les compagnons rémunérés, en s’appuyant sur des entretiens semi-structurés, ouverte, des entrevues en personne et d’élicitation des photos auto-pilotées (par lequel les individus prennent leur propres photos et en discuter plus tard dans les entretiens) avec 30 participants (15 compagnons, 8 clients et 7 informateurs clés). Les résultats ont révelé que, de plusieurs façons, les services fournis par les compagnons pour les clients qui vivent dans leurs propres maisons ressemblent aux soins à domicile basés sur les tâches, mais l’accent mis sur le travail est différent. Les relations sociales et émotionelles avec les clients sont au centre de leur travail. Les compagnons basés dans les établissements jouent un rôle unique, remplissant le vide laissé par les compressions budgetaires des ratios de dotation en personnel, qui garde les résidents âgés, souvent atteint de démence, impliqués et engagés dans le monde.
MicroRNAs: a new piece in the paediatric cardiovascular disease puzzle
Authors: Omran Ahmed , Elimam Dalia , Webster Keith A. , Shehadeh Lina A. , Yin Fei 
Published: February 2013

AbstractCardiovascular diseases in children comprise a large public health problem. The major goals of paediatric cardiologists and paediatric cardiovascular researchers are to identify the cause(s) of these diseases to improve treatment and preventive protocols. Recent studies show the involvement of microRNAs (miRs) in different aspects of heart development, function, and disease. Therefore, miR-based research in paediatric cardiovascular disorders is crucial for a better understanding of the underlying pathogenesis of the disease, and unravelling novel, efficient, preventive, and therapeutic means. The ultimate goal of such research is to secure normal cardiac development and hence decrease disabilities, improve clinical outcomes, and decrease the morbidity and mortality among children. This review focuses on the role of miRs in different paediatric cardiovascular conditions in an effort to encourage miR-based research in paediatric cardiovascular disorders.
Assessing Social Cognition and Pragmatic Language in Adolescents with Traumatic Brain Injuries
Authors: McDonald Skye , English Therese , Randall Rebekah , Longman Thea , Togher Leanne , Tate Robyn L. 
Published: February 2013

AbstractTraumatic brain injuries (TBI) in children and adolescents can impair social cognition and communication skills but there are few assessment tools suitable for adolescents. The Awareness of Social Inference Test (TASIT) uses professionally enacted audiovisual vignettes of everyday conversational exchanges and is a valid measure of social perception disorders in adults. This study examined its utility for assessing impairments in social cognition in a group of 16 adolescents with TBI, compared to a group of 16 typically developing (TD) adolescents. Adolescents with TBI were, on average, no different to their TD peers on TASIT 1 (emotion recognition) and TASIT 3 (recognizing lies and sarcasm when provided with additional cues) but performed more poorly on TASIT 2 which required them to interpret sarcastic and sincere conversational exchanges with few cues other than the demeanor of the speakers. Within the TBI group, poor performance on TASIT correlated to both relative and self-reported communication difficulties at home. It also correlated with IQ, face recognition and severity of injury as indexed by duration of post-traumatic amnesia. Overall, this study suggests TASIT is a valid measure for adolescents although it raised questions as to how effective normative data is for comparing performance in social cognition during childhood and adolescence. (JINS, 2013,19, 1–11)
Environmental Scanning Electron Microscopy Technique to Identify Asbestos Phases Inside Ferruginous Bodies
Authors: Croce Alessandro , Musa Maya , Allegrina Mario , Trivero Paolo , Rinaudo Caterina 
Published: February 2013

AbstractFerruginous bodies observed in lungs of patients affected by mesothelioma, asbestosis, and pulmonary carcinoma are important to relate the illness to exposure, environmental or occupational, to asbestos. Identification of the inorganic phase constituting the core of the ferruginous bodies, formed around asbestos but also around phases different from asbestos, is essential for legal purposes. Environmental scanning electron microscopy/energy dispersive spectroscopy was used to identify the fibrous mineral phase in the core of ferruginous bodies observed directly in thin sections of tissue, without digestion of the biological matrix. Spectra were taken with sequential analyses along a line crossing the core of the ferruginous bodies. By comparing the spectra taken near to and far from the core, the chemical elements that make up the core could be identified.
The cosmic distance scale and H0: Past, present, and future
Authors: Freedman Wendy L. 
Published: February 2013

AbstractTwenty years ago, there was disagreement at a level of a factor of two as regards the value of the expansion rate of the Universe. Ten years ago, a value that was good to 10% was established using the Hubble Space Telescope (HST), completing one of the primary missions that NASA designed and built the HST to undertake. Today, after confronting most of the systematic uncertainties listed at the end of the Key Project, we are looking at a value of the Hubble constant that is plausibly known to within 3%. In the near future, an independently determined value of H0 good to 1% is desirable to constrain the extraction of other cosmological parameters from the power spectrum of the cosmic microwave background in defining a concordance model of cosmology. We review recent progress and assess the future prospects for those tighter constraints on the Hubble constant, which were unimaginable just a decade ago.
Allan Sandage and the distance scale
Authors: Tammann G. A. , Reindl B. 
Published: February 2013

AbstractAllan Sandage returned to the distance scale and the calibration of the Hubble constant again and again during his active life, experimenting with different distance indicators. In 1952 his proof of the high luminosity of Cepheids confirmed Baade's revision of the distance scale (H0 ~ 250 km s−1 Mpc−1). During the next 25 years, he lowered the value to 75 and 55. Upon the arrival of the Hubble Space Telescope, he observed Cepheids to calibrate the mean luminosity of nearby Type Ia supernovae (SNe Ia) which, used as standard candles, led to the cosmic value of H0 = 62.3 ± 1.3 ± 5.0 km s−1 Mpc−1. Eventually he turned to the tip of the red giant branch (TRGB) as a very powerful distance indicator. A compilation of 176 TRGB distances yielded a mean, very local value of H0 = 62.9 ± 1.6 km s−1 Mpc−1 and shed light on the streaming velocities in the Local Supercluster. Moreover, TRGB distances are now available for six SNe Ia; if their mean luminosity is applied to distant SNe Ia, one obtains H0 = 64.6 ± 1.6 ± 2.0 km s−1 Mpc−1. The weighted mean of the two independent large-scale calibrations yields H0 = 64.1 km s−1 Mpc−1 within 3.6%.
The effects of physics and chemical-abundance uncertainties on the properties of lower-mass stars that are used as standard candles
Authors: VandenBerg Don A. 
Published: February 2013

AbstractThe distances to old stellar populations have traditionally been derived from three standard candles: the luminosity of the red-giant-branch tip, the absolute magnitudes of RR Lyrae stars, and the colour–magnitude-diagram loci of nearby subdwarfs. The distance-modulus uncertainties that are associated with these methods are still at the level of ±0.10–0.15 mag. Current stellar models are able to satisfy these age-independent constraints to well within their error bars, which are mainly owing to the uncertainties in the distances of the calibrating objects and, directly or indirectly, to chemical-abundance uncertainties. The impact of varying the physics and the assumed abundances in stellar models on the aforementioned standard candles is discussed, as is the use of the giant-branch bump luminosity to constrain the distance scale.
Toward improving the accuracy of Cepheid distances through parallax of pulsation
Authors: Mérand Antoine , Kervella Pierre , Aufdenberg Jason P. , Gallenne Alexandre 
Published: February 2013

AbstractImprovement of the calibration of the Cepheid period–luminosity relation (Leavitt's Law) is one of the main challenges to improve the accuracy of the Hubble constant, H0. Many parallax-of-pulsation methods are promising but have not yet delivered sufficiently accurate distances: observational biases, such as the projection factor, still dominate. We propose a global parallax-of-pulsation method, combining all observables (photometry, spectroscopy, and interferometry), to (i) reduce statistical errors, (ii) use the redundancy among observables to validate our approach, and (iii) achieve 2% accuracy for individual Cepheid distances.
The Baade–Becker–Wesselink technique and the fundamental astrophysical parameters of Cepheids
Authors: Rastorguev Alexey S. , Dambis Andrey K. , Zabolotskikh Marina V. , Berdnikov Leonid N. , Gorynya Natalia A. 
Published: February 2013

AbstractThe Baade–Becker–Wesselink (BBW) method remains one of most often used tools to derive a full set of Cepheid astrophysical parameters. The surface brightness version of the BBW technique was preferentially used during the past few decades to calculate Cepheid radii and to improve period–luminosity–colour relations. Its implementation requires a priori knowledge of Cepheid reddening values. We propose a new version of the BBW technique, which allows one to independently determine the colour excess and the intrinsic colour of a radially pulsating star, in addition to its radius, luminosity and distance. The new technique is a generalization of the Balona light curve-modelling approach. The method also allows calibration of the function F(CI0) = BC(CI0) + 10 log [Teff (CI0)] for the class of pulsating stars considered. We apply this technique to a number of classical Cepheids with very accurate light and radial-velocity curves. The new technique can also be applied to other pulsating variables, e.g., RR Lyrae stars. We also discuss the possible dependence of the projection factor on the pulsation phase.
The distance to the Small Magellanic Cloud from eclipsing binaries
Authors: Graczyk Dariusz , Pietrzyński Grzegorz , Pilecki Bogumił , Thompson Ian B. , Gieren Wolfgang , Konorski Piotr , Udalski Andrzej , Soszyński Igor 
Published: February 2013

AbstractA preliminary distance etimate to SMC 108.1.14904, a long-period eclipsing binary in the Small Magellanic Cloud, is presented. The binary system contains two bright, non-active G-type giants. Its orbital period is 185 days and the orbit is circular. Using surface brightness calibration, we obtain a distance modulus to the system of (m-M)= 19.02 ± 0.04 (statistical) ± 0.05 (systematic) mag, where the systematic error is dominated by uncertainties in the surface brightness calibration. This is a second eclipsing binary in the SMC analysed by our team.
Application of the Direct Distance Estimation procedure to eclipsing binaries in star clusters
Authors: Milone E. F. , Schiller S. J. 
Published: February 2013

AbstractWe alert the community to a paradigm method to calibrate a range of standard candles by means of well-calibrated photometry of eclipsing binaries in star clusters. In particular, we re-examine systems studied as part of our Binaries-in-Clusters program, and previously analyzed with earlier versions of the Wilson–Devinney light-curve modeling program. We make use of the 2010 version of this program, which incorporates a procedure to estimate the distance to an eclipsing system directly, as a system parameter, and is thus dependent on the data and analysis model alone. As such, the derived distance is accorded a standard error, independent of any additional assumptions or approximations that such analyses conventionally require.
The planetary nebula luminosity function
Authors: Ciardullo Robin 
Published: February 2013

AbstractAlthough the method has no theoretical explanation, the [Oiii]λ5007Å planetary nebula luminosity function (PNLF) is an extremely valuable tool for obtaining accurate (< 10%) extragalactic distances out to ~ 18 Mpc. Because the PNLF works in large galaxies of all Hubble types, it is one of the best tools we have for cross-checking the results of other methods and identifying systematic offsets between the Population I and Population II distance ladders. We review the PNLF's calibration and show that the method's Cepheid-derived zero point is virtually identical to that inferred from measurements of the tip of the red giant branch. We then compare the PNLF to the surface brightness fluctuations method and demonstrate that the latter's calibration yields a distance scale that is ~ 15% larger than that of the PNLF. We argue that this offset is likely due to a number of factors, including the effects of reddening on both of the techniques. We conclude by discussing the use of the PNLF for supernovae Type Ia calibration and considering the outstanding problems associated with the method.
The 6dFGS peculiar velocity field
Authors: Springob Christopher M. , Magoulas Christina , Colless Matthew , Jones D. Heath , Campbell Lachlan , Lucey John , Mould Jeremy , Erdoğdu Pirin 
Published: February 2013

AbstractThe 6dF Galaxy Survey (6dFGS) is an all-southern-sky galaxy survey, including 125,000 redshifts and a Fundamental Plane (FP) subsample of 10,000 peculiar velocities. This makes 6dFGS the largest peculiar-velocity sample to date. We have fitted the FP with a tri-variate Gaussian model using a maximum-likelihood approach, and derive the Bayesian probability distribution of the peculiar velocity for each of the 10,000 galaxies. We fit models of the velocity field, including comparisons to the field predicted from the redshift-survey density field, to derive the values of the redshift-space distortion parameter β, the bulk flow and the residual bulk flow in excess of that predicted from the density field. We compare these results to those derived by other authors and discuss the cosmological implications.
Testing the distance-duality relation to probe the morphology of galaxy clusters
Authors: Meng Xiao-Lei 
Published: February 2013

AbstractAiming at comparing different morphological models of galaxy clusters, we use two new methods to construct a cosmological-model-independent test of the distance-duality (DD) relation. The luminosity distances come from the Union2 compilation of Type Ia supernovae. The angular-diameter distances are given by the two cluster models of De Filippis et al. and Bonamente et al. The advantage of our new methods is that they can lead to reduced statistical errors. The morphologies of the cluster models are mainly focused on a comparison between the elliptical and spherical β models. The spherical β model is divided into two groups, in terms of different reduction methods of angular-diameter distances, i.e. the conservative and corrected spherical β models. Our results show that the DD relation is consistent with the elliptical β model at the 1σ confidence level (CL) for both methods, whereas for almost all spherical β-model parameterizations the DD relation can only be accommodated at the 3σ CL, particularly for the conservative spherical β model. To minimize systematic uncertainties, we also apply the test to the overlap sample, i.e. to the same set of clusters modeled by both De Filippis et al. and Bonamente et al. The DD relation is compatible with the elliptically modeled overlap sample at the 1σ CL; however, for most parameterizations the DD relation cannot be accommodated even at the 3σ CL by any of the two spherical β models. Therefore, it is reasonable that the marked triaxial ellipsoidal model is a better geometric hypothesis describing the structure of galaxy clusters than the spherical β model if the DD relation is valid for cosmological observations.
Revisiting the absolute-magnitude calibration of F-type supergiants and bright giants as a function of the equivalent width of the OIλ7774Å triplet
Authors: Dambis A. K. 
Published: February 2013

AbstractWe reduce the published measurements of the equivalent width of the oxygen triplet (Oiλ7774Å) to a single system and combine the resulting homogenized indices with revised Hipparcos parallaxes to derive the MK versus log[W(Oiλ7774Å)] absolute-magnitude calibration for bright F-type giants and supergiants and use the resulting calibration to estimate both the distance to the Large Magellanic Cloud and the parameters of the Galactic rotation curve.
Determination of the fundamental properties of an M31 globular cluster from main-sequence photometry
Authors: Ma Jun 
Published: February 2013

AbstractWe determined the age of the M31 globular cluster B379 using isochrones of the Padova stellar evolutionary models. At the same time, the cluster's metal abundance, its distance modulus, and reddening value were also obtained. The results obtained in this paper are consistent with previous determinations, including the age. Brown et al. constrained the age of B379 by comparing its color–magnitude diagram with isochrones of the 2006 VandenBerg models. Therefore, this paper confirms the consistency of the age scale of B379 between the Padova isochrones and the 2006 VandenBerg isochrones. The results of B379 obtained in this paper are: metallicity [M/H] = log(Z/Z⊙) = −0.325 dex, age τ = 11.0 ± 1.5 Gyr, reddening E(B − V) = 0.08 mag, and distance modulus (m − M)0 = 24.44 ± 0.10 mag. Using the metallicity, the reddening value and the distance modulus obtained in this paper, we constrained the age of B379 by comparing its multicolor photometry with theoretical stellar population synthesis models. The age of B379 obtained is 10.6−0.76+0.92 Gyr, which is in very good agreement with the determination from main-sequence photometry.