bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Classroom Quality with The RULER Approach to Social and Emotional Learning: Proximal and Distal Outcomes
Authors: Hagelskamp Carolin , Brackett Marc A. , Rivers Susan E. , Salovey Peter
Published: February 2013

The RULER Approach to Social and Emotional Learning (“RULER”) is designed to improve the quality of classroom interactions through professional development and classroom curricula that infuse emotional literacy instruction into teaching–learning interactions. Its theory of change specifies that RULER first shifts the emotional qualities of classrooms, which are then followed, over time, by improvements in classroom organization and instructional support. A 2‐year, cluster randomized controlled trial was conducted to test hypotheses derived from this theory. Sixty‐two urban schools either integrated RULER into fifth‐ and sixth‐grade English language arts (ELA) classrooms or served as comparison schools, using their standard ELA curriculum only. Results from multilevel modeling with baseline adjustments and structural equation modeling support RULER's theory of change. Compared to classrooms in comparison schools, classrooms in RULER schools exhibited greater emotional support, better classroom organization, and more instructional support at the end of the second year of program delivery. Improvements in classroom organization and instructional support at the end of Year 2 were partially explained by RULER's impacts on classroom emotional support at the end of Year 1. These findings highlight the important contribution of emotional literacy training and development in creating engaging, empowering, and productive learning environments.
Degradome sequencing reveals an endogenous microRNA target in C. elegans
Authors: Park June Hyun , Ahn Soungyub , Kim Soyoung , Lee Junho , Nam Jin-Wu , Shin Chanseok
Published: February 2013

Caenorhabditis elegans microRNAs (miRNAs) bind to partially complementary sequences in the 3′ untranslated region of target mRNAs, resulting in translational repression through mRNA destabilization. High‐throughput sequencing of RNA cleavage fragments was performed to directly detect miRNA‐directed cleavage targets in adult stage C. elegans. From this analysis, we found that miR‐249 directed the cleavage of the ZK637.6 transcript with extensive and evolutionarily conserved complementarity in nematode. In addition, expression of the ZK637.6 transcript was strongly dependent on the expression of miR‐249. These findings may lead to a better understanding of miRNA‐mediated gene regulation in nematodes.
General interaction mode of CIDE:CIDE complex revealed by a mutation study of the Drep2 CIDE domain
Authors: Lee Seung Mi , Park Hyun Ho
Published: February 2013

Drep2
and
Drep1
bind
by
blue native page
(View interaction)
Extracellular matrix components: An intricate network of possible biomarkers for lysosomal storage disorders?
Authors: Batzios Spyros P. , Zafeiriou Dimitrios I. , Papakonstantinou Eleni
Published: February 2013

Biomarkers are extremely important in the case of multisystemic diseases, such as lysosomal storage disorders (LSDs), which are often difficult to assess in clinical practice. Several studies demonstrated significant alterations in the expression of extracellular matrix (ECM) components in LSD patients, raising important questions in relation to their possible involvement in disease pathogenesis and providing evidence for their possible utility as disease biomarkers. This article provides an overview of the possible pathogenic correlations between LSDs and ECM. Data regarding the expression of these molecules are discussed. Finally, the possible implication of ECM components as therapeutic targets in this group of diseases along with the impact of the differential expression of these components in current LSD treatment will be critically addressed.
Avoiding poor health or approaching good health: Does it matter? The conceptualization, measurement, and consequences of health regulatory focus
Authors: Gomez Pierrick , Borges Adilson , Pechmann Cornelia (Connie)
Published: February 2013

This research presents a new scale, the health regulatory focus scale, which measures an individual's tendency to use promotion or prevention strategies in the pursuit of health goals. We conducted five studies in France to develop the scale which is made up of two subscales for prevention and promotion. We also tested the scale's psychometric properties and demonstrated its two‐factor dimensionality, internal and test–retest reliability, and convergent, nomological, predictive and discriminant validity. The health subscales showed good predictive validity in that they correlated with health behaviors better than the general regulatory focus subscales. For instance, health promotion focus predicted dentist visits while general promotion focus did not, and health prevention focus predicted the use of prescription and over‐the‐counter drugs while general prevention focus did not. Also as expected, general prevention focus predicted avoidance of risky vacation behaviors while health prevention focus did not. The health subscales either did not correlate or correlated weakly with positive and negative affectivity and general risk aversion indicating good discriminant validity. The one‐year test–retest reliabilities were adequate for both subscales.
Estrogen receptor‐α36 is involved in development of acquired tamoxifen resistance via regulating the growth status switch in breast cancer cells
Authors: Li Guangliang , Zhang Jing , Jin Ketao , He Kuifeng , Zheng Yi , Xu Xin , Wang Haohao , Wang Haiyong , Li Zhongqi , Yu Xiongfei , Teng Xiaodong , Cao Jiang , Teng Lisong
Published: February 2013

Acquired tamoxifen (TAM) resistance limits the therapeutic benefit of TAM in patients with hormone‐dependent breast cancer. The switch from estrogen‐dependent to growth factor‐dependent growth is a critical step in this process. However, the molecular mechanisms underlying this switch remain poorly understood. In this study, we established a TAM resistant cell sub line (MCF‐7/TAM) from estrogen receptor‐α (ER‐α66) positive breast cancer MCF‐7 cells by culturing ER‐α66‐positive MCF‐7 cells in medium plus 1 μM TAM over 6 months. MCF‐7/TAM cells were then found to exhibit accelerated proliferation rate together with enhanced in vitro migratory and invasive ability. And the estrogen receptor‐α36 (ER‐α36), a novel 36‐kDa variant of ER‐α66, was dramatically overexpressed in this in vitro model, compared to the parental MCF‐7 cells. Meanwhile, the expression of epidermal growth factor receptor (EGFR) in MCF‐7/TAM cells was significantly up‐regulated both in mRNA level and protein level, and the expression of ER‐α66 was greatly down‐regulated oppositely. In the subsequent studies, we overexpressed ER‐α36 in MCF‐7 cells by stable transfection and found that ER‐α36 transfected MCF‐7 cells (MCF‐7/ER‐α36) similarly exhibited decreased sensitivity to TAM, accelerated proliferative rate and enhanced in vitro migratory and invasive ability, compared to empty vector transfected MCF‐7 cells (MCF‐7/V). Real‐time qPCR and Western blotting analysis revealed that MCF‐7/ER‐α36 cells possessed increased EGFR expression but decreased ER‐α66 expression both in mRNA level and protein level, compared to MCF‐7/V cells. This change in MCF‐7/ER‐α36 cells could be reversed by neutralizing anti‐ER‐α36 antibody treatment. Furthermore, knock‐down of ER‐α36 expression in MCF‐7/TAM cells resulted in reduced proliferation rate together with decreased in vitro migratory and invasive ability. Decreased EGFR mRNA and protein expression as well as increased ER‐α66 mRNA expression were also observed in MCF‐7/TAM cells with down‐regulated ER‐α36 expression. In addition, blocking EGFR/ERK signaling in MCF‐7/ER‐α36 cells could restore the expression of ER‐α66 partly, suggesting a regulatory function of EGFR/ERK signaling in down‐regulation of ER‐α66 expression. In conclusion, our results indicated for the first time a regulatory role of ER‐α36 in up‐regulation of EGFR expression and down‐regulation of ER‐α66 expression, which could be an underlying mechanism for the growth status switch in breast tumors that contribute to the generation of acquired TAM resistance. And ER‐α36 could be considered a potential new therapeutic target in breast tumors which have acquired resistance to TAM.
Patient‐derived xenografts recapitulate molecular features of human uveal melanomas
Authors: Laurent Cécile , Gentien David , Piperno-Neumann Sophie , Némati Fariba , Nicolas André , Tesson Bruno , Desjardins Laurence , Mariani Pascale , Rapinat Audrey , Sastre-Garau Xavier , Couturier Jérôme , Hupé Philippe , de Koning Leanne , Dubois Thierry , Roman-Roman Sergio , Stern Marc-Henri , Barillot Emmanuel , Harbour J. William , Saule Simon , Decaudin Didier
Published: February 2013

We have previously developed a new method for the development and maintenance of uveal melanoma (UM) xenografts in immunodeficient mice. Here, we compare the genetic profiles of the primary tumors to their corresponding xenografts that have been passaged over time. The study included sixteen primary UMs and corresponding xenografts at very early (P1), early (P4), and late (P9) in vivo passages. The tumors were analyzed for mutation status of GNAQ, GNA11, GNAS, GNA15, BAP1, and BRAF, chromosomal copy number alterations using Affymetrix GeneChip® Genome‐Wide Human SNP6.0 arrays, gene expression profiles using GeneChip® Human Exon 1.0 ST arrays, BAP1 mRNA and protein expression, and MAPK pathway status using Reverse Phase Protein Arrays (RPPA). The UM xenografts accurately recapitulated the genetic features of primary human UMs and they exhibited genetic stability over the course of their in vivo maintenance. Our technique for establishing and maintaining primary UMs as xenograft tumors in immunodeficient mice exhibit a high degree of genetic conservation between the primary tumors and the xenograft tumors over multiple passages in vivo. These models therefore constitute valuable preclinical tool for drug screening in UM.
CREATING SYNERGIES BETWEEN CONSERVATION AGRICULTURE AND CATTLE PRODUCTION IN CROP–LIVESTOCK FARMS: A STUDY CASE IN THE LAKE ALAOTRA REGION OF MADAGASCAR
Authors: ANDRIARIMALALA J. H. , RAKOTOZANDRINY J. N. , ANDRIAMANDROSO A. L. H. , PENOT E. , NAUDIN K. , DUGUÉ P. , TILLARD E. , DECRUYENAERE V. , SALGADO P.
Published: February 2013

Conservation agriculture (CA) has been promoted as a strategy to cope with deterioration in soil fertility, but its adoption on smallholder farms in tropical areas remains limited. In Madagascar, livestock production is facing shortages in forage especially during the dry season. The value of cover crops used in CA as livestock feed could be an incentive to make this form of agriculture more acceptable in rural areas. To do so, farmers must find a trade-off between the use of biomass from cover crops for animal production and its maintenance on the soil to meet CA's criteria. In this study, we evaluated the impact of biomass flows (cover crops and manure) between cropping and cattle production in crop–livestock farms in the Lake Alaotra region. Surveys among crop–livestock farmers were used to calculate feed concentrate and mineral fertilizer equivalents. Our results show that on average 42, 22 and 10% of biomass production (dry matter basis) of Brachiaria spp., Stylosanthes guianensis and Vicia villosa, respectively, are used for livestock feeding. The economic benefit in feed concentrate equivalent is between €73 and €723/year per farm. The use of manure contributes, just as CA, to improve soil fertility without using external fertilizing resources. The economic benefit in mineral fertilizer equivalent is between €116 and €2365/year per farm. The integration of CA and livestock production shows, beyond the agronomic advantages, an obvious economic benefit, which is essential to secure the Malagasy agricultural systems. Moreover, this economic benefit is another argument for the dissemination of CA practices in rural areas.
Genetic risk prediction in a small cohort of healthy adults in Atlanta
Authors: ZHAO JING , ARAFAT DALIA , BRIGHAM KENNETH L. , GIBSON GREG
Published: February 2013

Compared with single markers, polygenic scores that evaluate the joint effects of multiple trait-associated variants are more effective in explaining the variance of traits and risk of diseases. In total, 182 CHDWB (Emory-Georgia Tech Center for Health Discovery and Well Being study) adults were genotyped to investigate the common variant contributions to three traits (height, BMI, serum triglycerides) and three diseases (coronary artery disease (CAD), type 2 diabetes (T2D) and asthma). Association was contrasted between weighted and simple allelic sum polygenic scores with quantitative traits, and with the Framingham risk scores for CAD and T2D. Although the cohort size is two or three orders of magnitude smaller than typical discovery cohorts, we were able to detect significant associations and to explain up to 5% of the traits by the genetic risk scores, despite a strong influence of outliers. An unexpected finding was that CAD-associated single nucleotide polymorphisms (SNPs) explain a significant amount of the variation for total serum cholesterol. Forward step-wise sequential addition of SNPs into the regression model showed that the top-ranked SNPs explain a large proportion of variance, whereas inclusion of gender and ethnicity also affect the performance of polygenic scores.
AA and the Redeployment of Temperance Literature
Authors: McGOWAN PHILIP
Published: February 2013

This essay is an examination that, primarily comparativist in its approach, links publication materials from the temperance and Prohibition periods with the Big Book to show how AA's narrative antidotes to the traumas of modernity (sited in alcohol abuse) were as much the product of premodernist and turn-of-the-century hysteria as they were an attempt to write a new chapter in America's relationship with alcohol based on contemporary medical and social research.
Piercing associated perichondritis of the pinna: are we treating it correctly?
Authors: Liu Z W , Chokkalingam P
Published: February 2013

Objective:

This paper reports a series of patients with sporadic pinna perichondritis who presented to a district general hospital over a period of 10 years. The data examined included the causative organism, risk factors and pattern of antibiotic use.

Method:

A retrospective analysis of diagnosed cases of pinna perichondritis from 2001 to 2012 was performed. A literature review of pinna perichondritis was carried out using Pubmed with the key words ‘pinna perichondritis’, ‘pinna abscess’, ‘pinna infection’ and ‘piercing’.

Results:

Pinna perichondritis was more likely to result from chondral than lobe piercings. The majority of cases were caused byPseudomonas aeruginosa.

Conclusion:

Most patients were not prescribed anti-pseudomonal antibiotics on presentation. This may result in persistent infection and long-term cosmetic defects.
Spermatophore and spermatozoal ultrastructure of the Mediterranean hermit crabPagurus excavatus(Paguridae: Anomura: Decapoda)
Authors: Tirelli Tina , Gamba Marco , Pessani Daniela , Tudge Christopher C.
Published: February 2013

The ultrastructure of the spermatophores and spermatozoa of the Mediterranean hermit crabPagurus excavatusare described, using transmission electron microscopy. The size of the different parts of the spermatophore and spermatozoa are given and their ultrastructure described and compared to similar data already present in the literature for other hermit crabs. The morphology and ultrastructure of the spermatophore and spermatozoa ofP. excavatusare species-specific, clearly distinguishing the species from the others already described. The spermatophore and spermatozoa show some similarities with those produced by other representatives of the genus. In particular, the tripartite spermatophore is divided into two halves by the lateral ridge and, as with the spermatophores produced by other species belonging to the genusPagurus, it is morphologically very different from any other Paguroidea. The spermatozoa are composed of an ovoidal acrosomal vesicle capped by the operculum; the acrosome has a length:width ratio of approximately 1.75, therefore larger than 1 as reported for all anomurans studied to date. At the base of the acrosomal vesicle, there is the thin cytoplasm, the large nucleus and three arms positioned to form a 120° angle between each other. The present description is an important additional step allowing for better understanding of the relationships among the different hermit crab taxa.
The opposition's policy influence through issue politicisation
Authors: Seeberg Henrik Bech
Published: February 2013

In a quantitative study using unique quarterly data across two decades, this article addresses the opposition's opportunities to influence policy; a topic that has been neglected in existing party-policy research. The idea that is developed is applied to a remarkable policy development on crime during the Danish leftwing government in the 1990s. Contrary to its policy position when it took office in 1993, the leftwing government repeatedly adopted severe restrictions to penal policy. The policy position of the rightwing opposition and its vehement and persistent criticism of the government provide an explanation, the article argues. Taking media coverage, public opinion, violence statistics, and the government's performance into account, the analysis shows that opposition criticism spurred the penal policy restrictions. Hence, by incorporating a policy agenda perspective, this article encourages a broadening of the perspective on parties’ policy influence. In particularly the opposition's opportunities to politicise issues and hereby influence policy.
Corpus-based research and pedagogy in EAP: From lexis to genre
Authors: Flowerdew Lynne
Published: February 2013

This plenary paper showcases current corpus-based research on written academic English, illustrating the tight links that exist between corpus research and pedagogic applications. I first explicate Sinclair's concept of the ‘lexical approach’, which underpins much corpus research and pedagogy. I then discuss studies which focus on individual lexical items, phraseology (including lexical bundles) and rhetorical functions. Finally, I examine studies that combine Swalesian move structure analysis with corpus analysis. Throughout the paper, I highlight the importance attached to lexis in both corpus research and pedagogic applications of corpus findings in the realm of written discourse in English for Academic Purposes (EAP), covering both general and more specific purposes.
Participation in environmental conservation and protected area management in Romania: A review of three case studies
Authors: STRINGER LINDSAY C. , PAAVOLA JOUNI
Published: February 2013

Since the collapse of Central and Eastern Europe's communist regimes in the early 1990s, the ensuing environmental, social and economic changes have permitted development of new forms of multi-level governance. However, a coherent participatory approach to environmental conservation is yet to emerge. This review examines the changing approaches in environmental conservation and protected area governance in Romania during the country's pre-communist, communist, transition and current European Union eras. Three case examples are examined in depth to assess how changing environmental governance is playing out in practice in Natura 2000 sites, in a national park, and on privately owned (unprotected) forest land. Similar to other countries in Central and Eastern Europe, Romania's environmental governance practices still face substantial challenges in consolidating an inclusive and integrated approach to environmental governance and conservation. A lack of historical involvement of communities in decision making, reluctance within government to drive forward more inclusive environmental governance approaches, and a lack of non-governmental organizations focusing on environmental conservation, have resulted in slow progress towards more inclusive environmental governance. Civil society and solutions for institutionalizing participation across all levels of governance are needed to reorient environmental governance towards a more inclusive and multi-stakeholder approach that better links economic, social and environmental objectives.
Rejection sensitivity as a mediator of the impact of childhood exposure to family violence on adult attachment behavior
Authors: Feldman Scott , Downey Geraldine
Published: February 2013

Substantial evidence indicates a link between exposure to family violence in childhood and troubled social relationships. We draw on attachment and social-cognitive theory to formulate a model of the mechanisms underlying this association. The model proposes that early experiences of overt rejection (e.g., physical maltreatment) or covert rejection (e.g., emotional neglect) are internalized as sensitivity to rejection. In this study, we operationalize sensitivity to rejection in social-cognitive terms as a tendency to expect and be concerned about rejection across a range of social situations. We hypothesize that rejection sensitivity mediates the link between exposure to family violence and adult attachment behavior. Data from a survey of 212 undergraduates support this hypothesis and also provide evidence that indicates sensitivity to rejection underlies both avoidant and ambivalent patterns of insecure adult attachment behavior. Overall, the results illustrate the power of a process approach to explaining the developmental sequelae of maltreatment.
Assessing the generalisability of the Pediatric Cardiac Quality of Life Inventory in the United Kingdom
Authors: Wray Jo , Brown Kate , Franklin Rodney , Cassedy Amy , Marino Bradley S.
Published: February 2013

Purpose

To demonstrate the generalisability of the Pediatric Cardiac Quality of Life Inventory in the United Kingdom.

Methods

Children and adolescents with heart disease were recruited from three tertiary paediatric cardiac centres in the United Kingdom and completed the Pediatric Cardiac Quality of Life Inventory. Item response option variability, total and subscale scores, patterns of correlation, and internal consistency were compared between the three sites.

Results

A total of 1537 participants – 768 children/adolescents and 769 parents – were evaluated from the three sites. Patterns of item response option variability were similar and acceptable for all samples – child, adolescent, parent of child, and parent of adolescent. Internal consistency was high (0.82–0.96) for all samples from each site, and item–subscale, subscale–subscale, subscale–total, and item–total correlations were moderate to excellent for each centre. Comparisons of patterns of subscale and total score correlations between the three sites revealed no significant differences.

Conclusion

Scores on the Pediatric Cardiac Quality of Life Inventory are generalisable in the United Kingdom, supporting the use of this measure for multi-centre studies of health-related quality of life of children and adolescents with heart disease.
A NOTE ON OPENNESS AND INFLATION TARGETING: IMPLICATIONS FOR THE UNPLEASANT FISCAL ARITHMETIC
Authors: de Mendonça Helder Ferreira , da Silva Veiga Igor
Published: February 2013

Emerging economies that have adopted inflation targeting and that combine low credibility, high public debt, and a high interest rate suffer from a typical problem. Increases in the interest rate to reduce departures of inflation from the target imply that a higher primary surplus is required for stabilizing public debt/GDP ratio. This tricky situation is known as “unpleasant fiscal arithmetic” (UFA). This article develops a theoretical model showing how increased financial openness and capital account liberalization can mitigate UFA. Furthermore, empirical evidence from the Brazilian case through OLS, GMM, and GMM system methods is offered. The findings show that increases in capital mobility and financial openness work as a commitment technology, which contributes to the success of the inflation targeting and thus reduces the risk of UFA.
Comparison of two school-based programmes for health behaviour change: the Belo Horizonte Heart Study randomized trial
Authors: Ribeiro Robespierre QC , Alves Luciana
Published: February 2013

Objective

To assess the efficacy of two school-based programmes to promote students’ willingness to engage in lifestyle changes related to eating habits and physical activity behaviours.

Design

Elementary school-based health promotion intervention, designed as a multicomponent experimental study, based on a behavioural epidemiological model.

Setting

Nine intervention and eight comparative public and private elementary schools.

Subjects

The goal was to determine the impact on the longitudinally assessed outcomes of two programmes that addressed healthy nutrition and active living in a cohort of 2038 children. The evaluations used pre-intervention and follow-up student surveys that were based on the Transtheoretical Model of the stages of behaviour change.

Results

In the intervention group, there were significant (P < 0·001) differences between the pre- and post-intervention times in the stages of change, with a reduction in the percentage of children at the pre-contemplation and contemplation stages and increased percentages at the preparation, action and maintenance stages, leading to healthier behaviours in fatty food consumption, fruit and vegetable consumption, physical activity and time spent in sedentary activities. The determinants of the behaviour stage were the intervention programme, the type of school and the presence of motivated teachers. The comparison group did not show significant differences between the pre- and post-intervention times for any of the stages of behaviour.

Conclusions

The intervention programme encouraged the students to make healthy lifestyle choices related to eating habits and physical activity behaviours.
Morphology Observation of Latex Particles with Scanning Transmission Electron Microscopy by a Hydroxyethyl Cellulose Embedding Combined with RuO4 Staining Method
Authors: Geng Xiang , Zhai Myra Xuemei , Sun Tong , Meyers Greg
Published: February 2013

Imaging of latex particles, especially those with low glass transition temperature (Tg) has been a challenging issue. Different sample preparation methods for characterization of the morphology of a poly(n-butyl acrylate)/polystyrene two-phase latex are discussed and compared in this study. A method via hydroxyethyl cellulose embedding combined with ruthenium tetraoxide (RuO4) staining for scanning transmission electron microscope (STEM) observation is developed. By using this method, the spherical shape of latex particles can be maintained without deformation. The degree of incorporation of RuO4 into latex particles and cellulose matrix is different, which makes latex particles readily identifiable from cellulose matrix under STEM. A series of latexes with different structures such as copolymer latex and organic-inorganic hybrid latex were also successfully investigated by this method. The results indicate this specimen preparation method can be applied to study the morphology of a wide range of latex systems.
ASYMPTOTIC ENUMERATION OF SYMMETRIC INTEGER MATRICES WITH UNIFORM ROW SUMS
Authors: MCKAY BRENDAN D. , MCLEOD JEANETTE C.
Published: February 2013

We investigate the number of symmetric matrices of nonnegative integers with zero diagonal such that each row sum is the same. Equivalently, these are zero-diagonal symmetric contingency tables with uniform margins, or loop-free regular multigraphs. We determine the asymptotic value of this number as the size of the matrix tends to infinity, provided the row sum is large enough. We conjecture that one form of our answer is valid for all row sums. An example appears in Figure 1.
The Gould's Belt Distances Survey
Authors: Loinard Laurent
Published: February 2013

Very Long Baseline Interferometry (VLBI) observations can provide the positions of compact radio sources with an accuracy of order 50 micro-arcseconds. This is sufficient to measure the trigonometric parallax and proper motions of any object within 500 pc of the Sun to better than a few percent. Because they are magnetically active, young stars are often associated with compact radio emission detectable using VLBI techniques. Here we show how VLBI observations have already constrained the distance to the most often studied nearby regions of star formation (Taurus, Ophiuchus, Orion, etc.) and have started to provide information about their internal structure and kinematics. We will then briefly describe a large project, the ‘Gould's Belt Distances Survey,’ which has been designed to provide a detailed view of star formation in the solar neighborhood using VLBI observations.
Direct distance determination using parallax: Techniques, promises and limitations
Authors: Lindegren Lennart
Published: February 2013

Determination of trigonometric parallaxes is one of the very few direct methods available for measuring cosmic distances, and the only one capable of reaching beyond the Solar System. It is fundamental both to determine the intrinsic properties of astrophysical objects and as the first step on the cosmic distance ladder. Steady improvements of instruments and techniques have extended the applicability of the parallax method to ever greater distances. However, it is not correct to say that the method is independent of physical assumptions. This review covers ground-based optical techniques, from Bessel's time to the present, as well as space observations and radio interferometry. Some emphasis is put on the physical limitations of the method, in particular its sensitivity to source structure and photocentric variability on different timescales.
Toward a VLBI resolution of the Pleiades distance controversy
Authors: Melis Carl , Reid M. J. , Mioduszewski A. J. , Stauffer J. R. , Bower G. C.
Published: February 2013

The Pleiades is the best-studied open cluster in the sky. It is one of the primary open clusters used to define the ‘zero-age main sequence,' and hence it serves as a cornerstone for programs which use main-sequence fitting to derive distances. This role is called into question by the ‘Pleiades distance controversy:' the distance to the Pleiades from Hipparcos of approximately 120 pc is significantly different from the distance of 133 pc derived using other techniques. To resolve this issue, we plan to use Very Long Baseline Interferometry to derive a new, independent trigonometric parallax distance to the Pleiades. In these proceedings we present our observational program and report some preliminary results.
Binaries and distances
Authors: Pourbaix D. , Arenou F. , Halbwachs J.-L. , Siopis C.
Published: February 2013

Gaia's five-year observation baseline might naively lead to the expectation that it will be possible to fit the parallax of any sufficiently nearby object with the default five-parameter model (position at a reference epoch, parallax and proper motion). However, simulated Gaia observations of a ‘model Universe’ composed of nearly 107 objects, 50% of which turn out to be multiple stars, show that the single-star hypothesis can severely affect parallax estimation and that more sophisticated models must be adopted. In principle, screening these spurious single-star solutions is rather straightforward, for example by evaluating the quality of the fits. However, the simulated Gaia observations also reveal that some seemingly acceptable single-star solutions can nonetheless lead to erroneous distances. These solutions turn out to be binaries with an orbital period close to one year. Without auxiliary (e.g., spectroscopic) data, they will remain unnoticed.
Determining distances to stars statistically from photometry
Authors: Newberg Heidi Jo
Published: February 2013

In determining the distances to stars within the Milky Way galaxy, one often uses photometric or spectroscopic parallaxes. In these methods, the type of each individual star is determined, and the absolute magnitude of that star type is compared with the measured apparent magnitude to determine individual distances. In this paper, we define the term statistical photometric parallax, in which statistical knowledge of the absolute magnitudes of stellar populations is used to determine the underlying density distributions of those stars. This technique has been used to determine the density distribution of the Milky Way's stellar halo and its component tidal streams, using very large samples of stars from the Sloan Digital Sky Survey. Most recently, the volunteer computing platform MilkyWay@home has been used to find the best-fitting model parameters for the density of these halo stars.
Spectroscopic distances to late-type stars
Authors: Bergemann Maria , Serenelli Aldo , Ruchti Gregory
Published: February 2013

A common approach to determining distances to stars without astrometric information is to compare stellar evolution models with parameters obtained from spectroscopic techniques. This method is routinely applied in the context of large-scale stellar surveys out to distances of several kpc. However, systematic errors may arise because of inaccurate spectroscopic parameters. We explore the effects of non-local thermodynamic equilibrium (NLTE) on the determination of surface gravities and metallicities for a large sample of metal-poor stars within approximately 10 kpc of the Sun. Using the improved Teff scale, we then show that stellar parameters estimated based on the widely used method of 1D LTE excitation-ionization balance of Fe results in distances which are systematically in error. For metal-poor giants, [Fe/H] ~ −2 dex, the distances can be overestimated by up to 70%. We compare the results with those from the Radial Velocity Experiment Survey catalogue (rave) for the stars in common, and find similar offsets.
The outer rotation curve project with VERA: Trigonometric parallax of IRAS 05168+3634
Authors: Sakai Nobuyuki , Honma Mareki , Nakanishi Hiroyuki , Sakanoue Hirofumi , Kurayama Tomoharu ,   the VERA collaboration
Published: February 2013

We present a measurement of the trigonometric parallax of IRAS 05168+3634 with VERA. The parallax is 0.532 ± 0.053 milli-arcsec, corresponding to a distance of 1.88+0.21−0.17 kpc. This is significantly closer than the previous distance estimate of 6 kpc based on a kinematic distance measurement. This drastic change in the source distance implies the need for revised values of not only the physical parameters of IRAS 05168+3634, but it also impies a different location in the Galaxy, placing it in the Perseus arm rather than the Outer arm. We also measured the proper motion of the source. A combination of the distance and proper motion with the systemic velocity yields a rotation velocity Θ = 227+9−11 km s−1 at the source position, assuming Θ0 = 240 km s−1. Our result, combined with previous VLBI results for six sources in the Perseus arm, indicates that the sources rotate systematically more slowly than the Galactic rotation velocity at the local standard of rest. In fact, we derive peculiar motions in the disk averaged over the seven sources in the Perseus arm of (Umean, Vmean) = (11 ± 3, −17 ± 3) km s−1, which indicates that these seven sources are moving systematically toward the Galactic Center and lag behind the overall Galactic rotation.
Cepheids and other variable stars and the distance to the Galactic Centre
Authors: Matsunaga Noriyuki
Published: February 2013

We review and discuss results of our survey of variable stars towards the Galactic Centre and their distances. In our near-infrared monitoring survey using IRSF/SIRIUS, we detected a number of Miras and Cepheids (both classical and type II) within 20 arcmin of the Galactic Centre. These distance indicators yield a distance to the Galactic Centre of between 7.5 and 8.5 kpc. A new calibration of the red clump also leads to a distance of ~ 8 kpc. For these indicators, which are luminosity-based, a large uncertainty resides in the correction for the foreground extinction, which depends on the reddening law. Nevertheless, our estimates are consistent with previous estimates based the kinematics of stars near the Galactic Centre, and this supports the reddening law we use.
Physical parameters for RR Lyrae stars in the sdss filter system
Authors: Catelan Márcio , Torrealba Gabriel I. , Cáceres Claudio , Smith Horace A. , De Lee Nathan , Fitzgerald Michael
Published: February 2013

We present a calibration of the metallicity and physical parameters (temperature, luminosity, gravity, mass, radius) for RR Lyrae stars using the ugrizsdss photometric system. Our work is based on calculations of synthetic horizontal branches (HBs), fully taking into account evolutionary effects for a wide range in metallicities and HB morphologies. We provide analytical fits that are able to provide all quantities mentioned with very high (internal) precision, based solely on mean sdss magnitudes and colors.
The Galactic Cepheid period–luminosity relation revisited using bona fide cluster Cepheids
Authors: Anderson Richard I. , Mowlavi Nami , Eyer Laurent
Published: February 2013

Classical Cepheids in Galactic open clusters (cluster Cepheids: CCs) have been studied extensively for multiple decades, thanks to their importance as calibrators of the Galactic Cepheid period–luminosity relation (PLR). Here we revisit the calibration of the Galactic PLR using a new sample of CCs, since even recent calibrations show significant discrepancies. The CC sample employed for the calibration is based on the preliminary results of a self-consistent, eight-dimensional all-sky census. This census is based mostly on literature data, supplemented with high-precision radial-velocity observations from both hemispheres. New CCs are identified from our census and the degree of confidence in membership is quantified for known candidates. Using only bona fide CCs, we obtain MV = (−3.08 ± 0.50) log P + (−0.94 ± 0.42) mag, which is in perfect agreement with the results by Sandage, Tammann, and Reindl, albeit with larger error bars and an rms of 0.21 mag. The key to obtaining a meaningful calibration is to employ accurate cluster distance moduli and space reddening values. A homogeneous study of all bona fide host clusters would be desirable to increase precision and confidence in the calibration.
Circumstellar envelopes of Cepheids: a possible bias affecting the distance scale?
Authors: Kervella Pierre , Gallenne Alexandre , Mérand Antoine
Published: February 2013

Circumstellar envelopes (CSEs) have been detected around many Cepheids, first based on long-baseline interferometry, and now also using other observing techniques. These envelopes are particularly interesting for two reasons: their presence could impact the Cepheid distance scale, and they may be valuable tracers of stellar mass loss. Here we focus on their potential impact on the calibration of the Cepheid distance scale. We consider the photometric contribution of the envelopes in the visible, near-, and thermal-infrared domains. We conclude that the impact of CSEs on the apparent luminosities of Cepheids is negligible at visible wavelengths and generally weak (<5%) in the near-infrared (λ ≈ 2 μm). In the thermal-infrared domain (λ ≈ 8 μm), the flux contribution of the CSEs differs depending on the pulsation period: it is relatively weak (<15%) for stars with periods shorter than P ≈ 10 days, but can reach ≈ 30% for long-period Cepheids. We specifically discuss the long-period Galactic Cepheid RS Puppis, which exhibits a very large circumstellar, dusty envelope, and we conclude that this is not a representative case. Overall, the contribution of CSEs to the usual period–luminosity relations (from the visible to the K band) is mostly negligible. They could affect calibrations at longer wavelengths, although the presence of envelopes may have been partially taken into account in the existing empirical calibrations.
The Araucaria Project: the Baade–Wesselink projection factor of pulsating stars and interferometric contribution to the eclipsing binaries technique of distance determination
Authors: Nardetto Nicolas , Challouf Mounir , Guiglion Guillaume , Mourard Denis , Gieren Wolfgang , Pietrzyński Grzegorz , Graczyk Dariusz
Published: February 2013

The international Araucaria Project aims to provide an improved local calibration of the extragalactic distance scale out to distances of a few Megaparsecs. We present a brief, up-to-date review of different results and ongoing projects to (i) better understand the Baade–Wesselink projection factor used in distance determinations based on Cepheids, and (ii) improve the eclipsing-binary technique of distance determination using CHARA/VEGA interferometric observations.
Asymptotic giant branch variables as extragalactic distance indicators
Authors: Whitelock Patricia A.
Published: February 2013

Large-amplitude asymptotic giant branch variables potentially rival Cepheid variables as fundamental calibrators of the distance scale, particularly if observations are made in the infrared, or where there is substantial interstellar obscuration. They are particularly useful for probing somewhat older populations, such as those found in dwarf spheroidal galaxies, elliptical galaxies or in the haloes of spirals. Calibration data from the Galaxy and new observations of various Local Group galaxies are described and the outlook for the future, with a calibration from Gaia and observations from the next generation of infrared telescopes, is discussed.
Rotational parallaxes of nearby galaxies
Authors: Brunthaler Andreas
Published: February 2013

Accurate geometric distances, which are inherently free of systematic effects are of very great importance for an independent recalibration of extragalactic distance estimators. Local Group galaxies are close enough for both primary and secondary distance indicators to be readily isolated in ground- and space-based observations. Astrometric accuracies of a few micro-arcseconds based on Very Long Baseline Interferometry (VLBI) observations of water masers in high-mass star-forming regions in nearby galaxies allow a measurement of the proper motions of these masers. Since these high-mass star-forming regions rotate with the galaxies, one can deduce a rotational parallax by comparing the known rotation curve with the proper motions of the masers. I provide an update of our previous rotation parallax of M33 and show first results of observations of the recently discovered water masers in the Andromeda galaxy (M31).
The distance to M31 in the era of precision cosmology
Authors: Valls-Gabaud David
Published: February 2013

With the advent of precision cosmology, where distances out to redshifts z < 0.6 can be measured to 2% precision on the basis of baryon acoustic oscillations, it appears essential to establish an accurate calibration of the primary and secondary indicators of the cosmological distance ladder. Here we review recent attempts at anchoring M31 very accurately using three independent methods, and discuss in detail the systematics that affect each. Two double-lined eclipsing binaries yield a distance to M31 which is precise to 4%. New Bayesian methods have been applied to determine the tip of the red-giant branch, even in sparsely populated colour–magnitude diagrams, and provide unique insights in the context of a precise three-dimensional distribution of the satellites in the M31 system. Over 2500 Cepheids have been identified in large-scale multi-colour surveys of M31, the largest homogeneous data set thus far obtained for any galaxy. A subset of 68 with periods longer than 10 days have been observed with the Wide-Field Camera 3 on board the Hubble Space Telescope, yielding the tightest-ever near-infrared period–luminosity relation, with a mean distance error of 1%. Combined with other measurements, the distance to M31 is now measured with a precision of 3%. Forthcoming improvements, and their implications, are also discussed.
Multiparametric scaling relations for dwarf irregular galaxies in different environments
Authors: Sharina M. E. , Karachentseva V. E. , Makarov D. I.
Published: February 2013

We study the correlations of rotation velocity and absolute magnitude with surface brightness for low surface brightness dwarf irregular galaxies (dIrrs). We find that isolated objects contribute most to the scatter in the Tully–Fisher relation (TFR). Excluding these extreme cases, we develop a three-parameter (luminosity, Hi line width at 20% of peak flux level, i.e., W20, effective surface brightness) TFR for 60 dIrrs (with revised Hubble type T > 8) in the Local Volume (LV) with Cepheid and tip-of-the-red-giant-branch distance measurements. The relation is applied to galaxies of the same morphological type with radial velocities vLG ≤ 3500 km s−1 in the Local Supercluster. We obtained surface photometry and determined structural parameters using sdss images. The rotational velocities and derived photometric parameters for most galaxies in small groups agree well with those corresponding to the three-parameter TFR. However, isolated galaxies appear to have systematically lower surface brightnesses and longer scale lengths for the same luminosity than galaxies in small groups. This may indicate on average twice larger Hi-to-optical disk size ratios for our sample of isolated dIrrs, because their Hi surface densities calculated using the optical diameters look normal.
The tip-of-the-red-giant-branch distance indicator and the structure of the nearest galaxy groups
Authors: Makarova Lidia , Makarov Dmitry
Published: February 2013

The tip of the red giant branch (TRGB) is one of the most accurate distance indicators to galaxies in the Local Universe (for distances up to 8–10 Mpc). A distance accuracy as high as 5% can be achieved with the recently developed maximum-likelihood implementation of the TRGB method and modern calibrations. In this paper, we consider in detail TRGB distance determinations to nearby groups of galaxies (within 8 Mpc). We discuss the photometric accuracy and describe colour–magnitude-diagram features of nearby dwarf galaxies and their influence on the accuracy of distance determination. We have determined accurate structures of the two nearest galaxy groups, M81 and Cen A, using observations of galaxies in these groups with the Hubble Space Telescope's WFPC2 and ACS instruments. The new technique allows us to see new details in the distribution of galaxies in the Canes Venatici i Cloud.
The planetary nebulae luminosity function and distances to the Virgo, Hydra i, and Coma Clusters
Authors: Arnaboldi Magda , Longobardi Alessia , Gerhard Ortwin , Okamura S.
Published: February 2013

The luminosity function of planetary nebula populations in galaxies at distances within 10–15 Mpc exhibits a cut-off at bright magnitudes and a functional form that is observed to be invariant among different galactic morphological types. Therefore, it is used as a secondary distance indicator applicable to both early- and late-type galaxies. Recent deep surveys of planetary nebula populations in brightest cluster galaxies (BCGs) seem to indicate that their luminosity functions deviate from those observed in the nearby galaxies. We discuss the evidence for such deviations in the Virgo Cluster, and indicate which physical mechanisms may alter the evolution of a planetary nebula envelope and its central star in the halo of BCGs. We then discuss preliminary results for distances to the Virgo, Hydra i, and Coma Clusters based on the observed planetary nebulae luminosity functions.