416 research outputs found
HST/WFPC2 imaging of the circumnuclear structure of LLAGNs. I Data and nuclear morphology
To advance our knowledge of the nature of the central source in LLAGNs and
its relation with stellar clusters, we are carrying out several imaging
projects with HST at near-UV, optical and near-IR wavelengths. In this paper,
we present the first results obtained with observations of the central regions
of 57 LLAGNs imaged with the WFPC2 through any of the V (F555W, F547M, F614W)
and I (F791W, F814W) filters that are available in the HST archive. The sample
contains 34% of the LINERs and 36% of the TOs in the Palomar sample. The mean
spatial resolution of these images is 10 pc. With these data we have built an
atlas that includes structural maps for all the galaxies, useful to identify
compact nuclear sources and, additionally, to characterize the circumnuclear
environment of LLAGNs, determining the frequency of dust and its morphology.
The main results obtained are: 1) We have not found any correlation between the
presence of nuclear compact sources and emission-line type. Thus, nucleated
LINERs are as frequent as nucleated TOs. 2) The nuclei of "Young-TOs" are
brighter than the nuclei of "Old-TOs" and LINERs. These results confirm our
previous results that Young-TOs are separated from other LLAGNs classes in
terms of their central stellar population properties and brightness. 3)
Circumnuclear dust is detected in 88% of the LLAGNs, being almost ubiquitous in
TOs. 4) The dust morphology is complex and varied, from nuclear spiral lanes to
chaotic filaments and nuclear disk-like structures. Chaotic filaments are as
frequent as dust spirals; but nuclear disks are mainly seen in LINERs. These
results suggest an evolutionary sequence of the dust in LLAGNs, LINERs being
the more evolved systems and Young-TOs the youngest. The full collection of
figures are at http://www.iaa.es/~rosa/research/LLAGNs2007/LLAGNs-HSTIma1.htmlComment: Paper accepted in AJ, pdf file and the full collection of figures are
at the ULR: http://www.iaa.es/~rosa/research/LLAGNs2007/LLAGNs-HSTIma1.htm
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How Emerging Organizations Take Form: The Role of Imprinting and Values in Organizational Bricolage
We examine how emerging organizations acquire shape by drawing on multiple organizational forms, a process we call organizational bricolage. Studying Indymedia London, a grassroots media collective, we propose a grounded theory of organizational bricolage that identifies how various types of organizational forms are selected and how they are instantiated into the organization. Whereas extant research has emphasized imprinting as a primary mechanism shaping newly founded organizations, we point to the additional role of organizational values. Emerging organizations augment their imprinted forms by using ancillary forms aligned with their organizational values and reinforce their core features by differentiating themselves from antagonistic forms that conflict with their values. We contribute to the literature on organizational formation by developing a process model that details how imprinted forms are subsequently modified. Moreover, we extend theories of bricolage by specifying the limits to the relative arbitrariness of bricolage as an activity, and we contribute to the study of organizational values by suggesting that they act as a focusing device shaping organizational structure
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Mitigation of Moral Hazard and Adverse Selection in Venture Capital Financing: The Influence of the Country’s Institutional Setting
A venture capitalist (VC) needs to trade off benefits and costs when attempting to mitigate agency problems in their investor-investee relationship. We argue that signals of ventures complement the VC’s capacity to screen and conduct a due diligence during the pre-investment phase, but its attractiveness may diminish in institutional settings supporting greater transparency. Similarly, whereas a VC may opt for contractual covenants to curb potential opportunism by ventures in the post-investment phase, this may only be effective in settings supportive of shareholder rights enforcement. Using an international sample of VC contracts, our study finds broad support for these conjectures. It delineates theoretical and practical implications for how investors can best deploy their capital in different institutional settings whilst nurturing their relationships with entrepreneurs
Composition of the Top Management Team and Firm International Diversification
This study investigates the impact of various top management team characteristics on firm international diversification. Relying on data from 126 firms in the electronics industry, we find that certain top management team characteristics are related to international expansion. Specifically, results indicate that lower average age, higher average tenure, higher average elite education, higher average international experience, and higher tenure heterogeneity are associated with firm international diversification. The study reinforces the importance of top management team composition in internationalization decisions and suggests further research in this context.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline
Business networks and localization effects for new Swedish technology-based firms’ innovation performance
This study examines the business networks and localization effects for new technology-based firms (NTBFs) in the context of innovation performance (the number of patents and product differentiation). In this regard, the study includes 28 variables. A survey was conducted in 2016 with 401 Swedish NTBFs that were small and young (the employment mean was 1.80 and the average age of each firm was 28.3\ua0months). The biggest category of NTBFs was knowledge-intensive high-technology services, followed by medium high-technology manufacturing, and high-technology manufacturing. Hypotheses on how business networks and localization are related to innovation performance were tested using principal component analysis, correlation analysis, and regression analysis. The results show that the primary significant factor for innovation performance regarding business networks and localization dimensions are professional network services, while industrial and regional areas also have a positive relationship on product differentiation. Our study also shows that innovation performance enhances firms’ abilities to access external financing through professional network services (e.g., venture capital companies)
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