6,338 research outputs found
Maximizing Repository Exposure
4th International Conference on Open RepositoriesThis presentation was part of the session : Conference PostersEnhancing online visibility for an institution or its (scientific) digital output, is one of the major goals in many repository projects. This proposal attempts to identify different repository properties, that have an influence on successful online exposure, tries to measure these properties and provides recommendations on optimizing these properties.@mire N
Proper motion survey with the 48-inch Schmidt telescope. 30: Proper motions for 1357 faint stars
A catalog of the proper motion of the faint stars and associated data is presented
Maximally rotating waves in AdS and on spheres
We study the cubic wave equation in AdS_(d+1) (and a closely related cubic
wave equation on S^3) in a weakly nonlinear regime. Via time-averaging, these
systems are accurately described by simplified infinite-dimensional quartic
Hamiltonian systems, whose structure is mandated by the fully resonant spectrum
of linearized perturbations. The maximally rotating sector, comprising only the
modes of maximal angular momentum at each frequency level, consistently
decouples in the weakly nonlinear regime. The Hamiltonian systems obtained by
this decoupling display remarkable periodic return behaviors closely analogous
to what has been demonstrated in recent literature for a few other related
equations (the cubic Szego equation, the conformal flow, the LLL equation).
This suggests a powerful underlying analytic structure, such as integrability.
We comment on the connection of our considerations to the Gross-Pitaevskii
equation for harmonically trapped Bose-Einstein condensates.Comment: 17 page
Aggregate party identification in Germany: the effects of consumer confidence and government approval.
Partisanship has been the object of extensive scholarly attention. Because individual partisanship seemed relatively stable and insensitive to short term forces, aggregate partisanship was long thought to display no meaningful variation. This view was challenged by MacKuen et al. (1989), who found that aggregate partisanship in the United States is a¤ected by consumer con…dence and presidential approval. This paper studies aggregate party identi…cation in Germany, and how it has evolved in the past thirty years. Speci…cally, we analyze the impact of consumer con…dence and government approval on party identi…cation. We conclude that rises in consumer con…dence and government approval do indeed lead to increases in identi…cation with the main governing parties.
Towards a domain-specific approach to the study of parental psychological control: distinguishing between dependency-oriented and achievement-oriented psychological control
Theory and research suggest that psychologically controlling parenting can be driven by parental concerns in two different domains, that is, interpersonal closeness and achievement. Three studies addressing this hypothesis are presented. Study 1 provides evidence for the validity of the Dependency-Oriented and Achievement-Oriented Psychological Control Scale (DAPCS), a new measure assessing psychological control in these two domains. Study 2 showed that dependency-oriented and achievement-oriented psychological control were related in expected ways to parental separation anxiety and perfectionism in a sample of mothers and fathers. Finally, Study 3 showed that dependency-oriented and achievement-oriented psychological control were differentially related to middle adolescent dependency and self-criticism and that these personality features act as specific intervening variables between the domain-specific expressions of psychological control and depressive symptoms. It is argued that the distinction between two domain-specific expressions of psychological control may allow for a more intricate analysis of the processes involved in intrusive parenting
The Solar Neighborhood XXVII: Discovery of New Proper Motion Stars with mu > 0.18 "/yr in the Southern Sky with 16.5 > R_59F > 18.0
Here we present 1584 new southern proper motion systems with mu > 0.18 "/yr
and 16.5 > R_59F > 18.0. This search complements the six previous
SuperCOSMOS-RECONS (SCR) proper motion searches of the southern sky for stars
within the same proper motion range, but with R_59F < 16.5. As in previous
papers, we present distance estimates for these systems and find that three
systems are estimated to be within 25 pc, including one, SCR 1546-5534,
possibly within the RECONS 10 pc horizon at 6.7 pc, making it the second
nearest discovery of the searches. We find 97 white dwarf candidates with
distance estimates between 10 and 120 pc, as well as 557 cool subdwarf
candidates. The subdwarfs found in this paper make up nearly half of the
subdwarf systems reported from our SCR searches, and are significantly redder
than those discovered thus far. The SCR searches have now found 155 red dwarfs
estimated to be within 25 pc, including 10 within 10 pc. In addition, 143 white
dwarf candidates and 1155 cool subdwarf candidates have been discovered. The
1584 systems reported here augment the sample of 4724 systems previously
discovered in our SCR searches, and imply that additional systems fainter than
R_59F = 18.0 are yet to be discovered.Comment: 11 pages of text, seven figure
A clinically relevant model of osteoinduction: a process requiring calcium phosphate and BMP/Wnt signalling
In this study, we investigated a clinically relevant model of in vivo ectopic bone formation utilizing human periosteum derived cells (HPDCs) seeded in a Collagraft carrier and explored the mechanisms by which this process is driven. Bone formation occurred after eight weeks when a minimum of one million HPDCs was loaded on Collagraft carriers and implanted subcutaneously in NMRI nu/nu mice. De novo bone matrix, mainly secreted by the HPDCs, was found juxta-proximal of the calcium phosphate (CaP) granules suggesting that CaP may have triggered the 'osteoinductive program'. Indeed, removal of the CaP granules by ethylenediaminetetraacetic acid decalcification prior to cell seeding and implantation resulted in loss of bone formation. In addition, inhibition of endogenous bone morphogenetic protein and Wnt signalling by overexpression of the secreted antagonists Noggin and Frzb, respectively, also abrogated osteoinduction. Proliferation of the engrafted HPDCs was strongly reduced in the decalcified scaffolds or when seeded with adenovirus-Noggin/Frzb transduced HPDCs indicating that cell division of the engrafted HPDCs is required for the direct bone formation cascade. These data suggest that this model of bone formation is similar to that observed during physiological intramembranous bone development and may be of importance when investigating tissue engineering strategies.Published versio
School size effects on achievement in secondary education : evidence from The Netherlands, Sweden and the USA
This paper reports the results of an investigation into the relationship between school size and achievement. The study examined the impact of school size on mathematics achievement in Dutch, Swedish, and American secondary education and on science achievement in the Netherlands. The following research questions were explored: (1) Is school size related to achievement independently of student background characteristics, such as sex, achievement motivation, socioeconomic status, and cognitive aptitude? (2) Is the effect of school size related to any of the before mentioned background characteristics? (3) Does the effect of school size on achievement differ among the educational systems of the Netherlands, Sweden, and the United States? (4) Is the effect of school size the same for different measures of student achievement (mathematics versus science)? Datasets from two international studies sponsored by the International Association for the Evaluation of Educational Achievement were analyzed - the Second International Mathematics Study (SIMS) and the Second International Science Study (SISS). The findings found little empirical evidence for the existence of school-size effects on achievement in any of the three countries, possibly because school size and curriculum comprehensiveness are not strongly related in these countries. Some useful additional information regarding the robustness of the detected relationships between the five covariates and student achievement is presented
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