25,588 research outputs found
Searching for chemical inhomogeneities in Open Clusters: Analysis of the CN and CH Molecular Band Strengths in NGC 2158, NGC 2420, NGC 2682, NGC 7789 and Berkeley 29
Context: The total mass of a cluster, being the main parameter determining
its ability to host more than one stellar generation, may constitute a
threshold below which the cluster is able to form only a single stellar
population. AIms: Our goal is to investigate the existence of star-to-star
variations of CN and CH band strengths, related to the N and C abundances,
respectively, among the stars in five open cluster (NGC 2158, NGC 2420, NGC
2682, NGC 7789 and Berkeley 29) similar to those observed in globular clusters
and linked with the existence of multiple populations therein. Since these
systems are less massive than globulars, our results may allow us to constrain
the lower mass necessary to form more than one stellar population. Methods: We
measured the strength of the CN and CH bands, which correlate with the C and N
abundances, using four molecular indices in low-resolution SDSS/SEGUE spectra.
Results: We found that for four of the open clusters (NGC 2158, NGC 2420, NGC
2682 and Berkeley 29) all the stars studied in each of them have similar CN and
CH band strengths within the uncertainties since neither anomalous spreads nor
bimodalities have been detected in their CN and CH distributions. In contrast,
for NGC 7789 we found an anomalous spread in the strength of the CN molecular
band at 3839 \AA which is larger than the uncertainties. However, the small
number of stars studied in this cluster implies that further analysis is needed
to confirm the existence of chemical inhomogeneities in this cluster.Comment: 11 pages, 9 figures, Accepted for publication in A&A, Tables 7, 8 and
9 will be publish onlin
Power, Policy, Profit: The Spanish Language in the United States
Over the past several decades, the Spanish language has been considered secondary to English, specifically in the United States. However, this paper argues that Spanish is one of the primary languages in the country because it is the second most spoken language, despite efforts to maintain a monolingual nation. Due to the impact of capitalism, if one’s first language is not English, they are separated and viewed as inferior in society. After providing background on the history of Spanish in the United States, this paper explores the impact of power, Americanization, education and cheap work on the Spanish language with data from various articles and the United States Census. Spanish continues to be a primary language in the United States, even with capitalism constantly attempting to exploit the language and those who speak it
BPS Skyrme neutron stars in generalized gravity
We study the coupling of nuclear matter described by the BPS Skyrme model to
generalized gravity. Concretely, we consider the Starobinsky model which
provides the leading-order correction to the Einstein-Hilbert action. Static
solutions describing neutron stars are found both for the full field theory and
for the mean-field approximation. We always consider the full Starobinsky model
in the nonperturbative approach, using appropriately generalized shooting
methods for the numerical neutron star calculations. Many of our results are
similar to previous investigations of neutron stars for the Starobinsky model
using other models of nuclear matter, but there are some surprizing
discrepancies. The "Newtonian mass" relevant for the surface redshift, e.g.,
results larger than the ADM mass in our model, in contrast to other
investigations. This difference is related to the particularly high stiffness
of nuclear matter described by the BPS Skyrme model and offers an interesting
possibility to distinguish different models of nuclear matter within
generalized gravity.Comment: LaTex, 28 pages, 13 figures; v2: minor change
Employment deconcentration in European metropolitan areas: A comprehensive comparison and policy implications
This chapter features a cross-national comparison of economic deconcentration in 12 European metropolitan areas analysing two attributes of employment deconcentration: the magnitude, which refers to the scale of deconcentration; and the physical form. The discussion is positioned in the framework of two dimensions of governance systems: welfare-state regime and central-local government relations. Our expectation that deconcentration would take place on a smaller scale and in a more concentrated form in comprehensive welfare state systems than in liberal regimes is confirmed for one decentralized comprehensive welfare state case and three decentralized liberal state metropolitan areas, but not for the other seven cases.
Arguments accounting for this mismatch are put forward. In addition, the effects of deconcentration on the quality of life and the impact of policies are discussed
Understanding the effect of smart retail brand - consumer communications via mobile instant messaging (MIM) - an empirical study in the Chinese context
Faced with competitive forces, retailers are innovating by adopting ‘smart’ technologies such as contactless, omni-channel, ubiquitous computing, social networking and mobile apps. This paper examines consumer behavior responses during the use of a mobile instant messaging (MIM) application channel adopted by a Chinese pure-play retailer. MIM is text-based, real-time, mobile computer-mediated communication technology accomplishing real-time interaction with other users regardless of location. WeChat, a full service MIM application, contains functional and social features including SMS, MMS, LBS, photo sharing, voice message, video calls and “Moments” sharing, which is its social propagating feature. There is a paucity of literature on the role of MIM in building relationships and especially, the relevance of emotion and WOM for consumers engaging in MIM human-computer interactions. The model tested was derived from prior research on trust and also Stimuli-Organism-Response (SOR) that depicts the effects of environmental/informational stimuli on consumers’ responses. Specific research objectives included investigating the prediction that environmental stimuli comprising socialness perception, media richness, and involvement induce a positive emotional state, which results in positive WOM. The study employed a quantitative approach using a questionnaire posted on a WeChat (MIM) channel. The sample comprised Chinese WeChat users, typically young consumers (n=486). SEM was used to analyze the data. Prior research has indicated that building relationships with consumers is more difficult when the relationships are consumer-computer as compared to consumer-person (face-to-face). The findings of this study suggest that such a negative effect can be alleviated by the use of MIM, which is associated with socialness perception, media richness, consumer involvement, emotional connections and positive WOM. To the authors’ knowledge, this study is original in integrating socialness perception, media richness and WOM into the SOR framework. The implications for practitioners are discussed, relating in particular to retailers’ need to be aware of the extent to which consumers are willing to engage with MIM applications
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