465 research outputs found
Multiple agency perspective, family control, and private information abuse in an emerging economy
Using a comprehensive sample of listed companies in Hong Kong this paper investigates how family control affects private information abuses and firm performance in emerging economies. We combine research on stock market microstructure with more recent studies of multiple agency perspectives and argue that family ownership and control over the board increases the risk of private information abuse. This, in turn, has a negative impact on stock market performance. Family control is associated with an incentive to distort information disclosure to minority shareholders and obtain private benefits of control. However, the multiple agency roles of controlling families may have different governance properties in terms of investors’ perceptions of private information abuse. These findings contribute to our understanding of the conflicting evidence on the governance role of family control within a multiple agency perspectiv
Thermal effects in high density polyethylene and low density polyethylene at high hydrostatic pressures
The temperature changes as a result of rapid hydrostatic pressure applications are reported for high density polyethylene (HDPE) and low density polyethylene (LDPE) in the reference temperature range from 298 to 423 K and in the pressure range from 13.8 to 200 MN m −2 . The adiabatic temperature changes were found to be a function of pressure and temperature. A curve fitting analysis showed that the empirical curve (∂/∂ P ) = ab (Δ P ) b−1 described the experimental thermoelastic coefficients obtained from the experiments. The data were analyzed by determining the predicted thermoelastic coefficients derived from the Thomson equation (∂/∂ P ) θ = α T 0 /ϱ C p . The experimental and predicted Grüneisen parameter γ T were also determined.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44687/1/10853_2005_Article_BF01132919.pd
Exo-C: a probe-scale space observatory for direct imaging and spectroscopy of extrasolar planetary systems
"Exo-C" is NASAs first community study of a modest aperture space telescope mission that is optimized for high contrast observations of exoplanetary systems. The mission will be capable of taking optical spectra of nearby exoplanets in reflected light, discovering previously undetected planets, and imaging structure in a large sample of circumstellar disks. It will obtain unique science results on planets down to super-Earth sizes and serve as a technology pathfinder toward an eventual flagship-class mission to find and characterize habitable Earth-like exoplanets. We present the mission/payload design and highlight steps to reduce mission cost/risk relative to previous mission concepts. Key elements are an unobscured telescope aperture, an internal coronagraph with deformable mirrors for precise wavefront control, and an orbit and observatory design chosen for high thermal stability. Exo-C has a similar telescope aperture, orbit, lifetime, and spacecraft bus requirements to the highly successful Kepler mission (which is our cost reference). Much of the needed technology development is being pursued under the WFIRST coronagraph study and would support a mission start in 2017, should NASA decide to proceed. This paper summarizes the study final report completed in March 2015.United States. National Aeronautics and Space Administration. Astrophysics Divisio
Exo-C: a probe-scale space observatory for direct imaging and spectroscopy of extrasolar planetary systems
"Exo-C" is NASAs first community study of a modest aperture space telescope mission that is optimized for high contrast observations of exoplanetary systems. The mission will be capable of taking optical spectra of nearby exoplanets in reflected light, discovering previously undetected planets, and imaging structure in a large sample of circumstellar disks. It will obtain unique science results on planets down to super-Earth sizes and serve as a technology pathfinder toward an eventual flagship-class mission to find and characterize habitable Earth-like exoplanets. We present the mission/payload design and highlight steps to reduce mission cost/risk relative to previous mission concepts. Key elements are an unobscured telescope aperture, an internal coronagraph with deformable mirrors for precise wavefront control, and an orbit and observatory design chosen for high thermal stability. Exo-C has a similar telescope aperture, orbit, lifetime, and spacecraft bus requirements to the highly successful Kepler mission (which is our cost reference). Much of the needed technology development is being pursued under the WFIRST coronagraph study and would support a mission start in 2017, should NASA decide to proceed. This paper summarizes the study final report completed in March 2015
Nonradioactive, ultrasensitive site-specific protein–protein photocrosslinking: interactions of α-helix 2 of TATA-binding protein with general transcription factor TFIIA and transcriptional repressor NC2
We have developed an approach that enables nonradioactive, ultrasensitive (attamole sensitivity) site-specific protein–protein photocrosslinking, and we have applied the approach to the analysis of interactions of α-helix 2 (H2) of human TATA-element binding protein (TBP) with general transcription factor TFIIA and transcriptional repressor NC2. We have found that TBP H2 can be crosslinked to TFIIA in the TFIIA–TBP–DNA complex and in higher order transcription–initiation complexes, and we have mapped the crosslink to the ‘connector’ region of the TFIIA α/β subunit (TFIIAα/β). We further have found that TBP H2 can be crosslinked to NC2 in the NC2–TBP–DNA complex, and we have mapped the crosslink to the C-terminal ‘tail’ of the NC2 α-subunit (NC2α). Interactions of TBP H2 with the TFIIAα/β connector and the NC2α C-terminal tail were not observed in crystal structures of TFIIA–TBP–DNA and NC2–TBP–DNA complexes, since relevant segments of TFIIA and NC2 were not present in truncated TFIIA and NC2 derivatives used for crystallization. We propose that interactions of TBP H2 with the TFIIAα/β connector and the NC2α C-terminal tail provide an explanation for genetic results suggesting importance of TBP H2 in TBP–TFIIA interactions and TBP–NC2 interactions, and provide an explanation—steric exclusion—for competition between TFIIA and NC2
The JWST Resolved Stellar Populations Early Release Science Program VI. Identifying Evolved Stars in Nearby Galaxies
We present an investigation of evolved stars in the nearby star-forming
galaxy WLM, using NIRCam imaging from the JWST resolved stellar populations
early-release science (ERS) program. We find that various combinations of the
F090W, F150W, F250M, and F430M filters can effectively isolate red supergiants
(RSGs) and thermally-pulsing asymptotic giant branch (TP-AGB) stars from one
another, while also providing a reasonable separation of the primary TP-AGB
subtypes: carbon-rich C-type stars and oxygen-rich M-type stars. The
classification scheme we present here agrees very well with the
well-established Hubble Space Telescope (HST) medium-band filter technique. The
ratio of C to M-type stars (C/M) is 0.80.1 for both the new JWST and the
HST classifications, which is within one sigma of empirical predictions from
optical narrow-band CN and TiO filters. The evolved star colors show good
agreement with the predictions from the PARSECCOLIBRI stellar evolutionary
models, and the models indicate a strong metallicity dependence that makes
stellar identification even more effective at higher metallicity. However, the
models also indicate that evolved star identification with NIRCam may be more
difficult at lower metallicies. We test every combination of NIRCam filters
using the models and present additional filters that are also useful for
evolved star studies. We also find that 90\% of the dusty evolved
stars are carbon-rich, suggesting that carbonaceous dust dominates the
present-day dust production in WLM, similar to the findings in the Magellanic
Clouds. These results demonstrate the usefulness of NIRCam in identifying and
classifying dust-producing stars without the need for mid-infrared data.Comment: 15 page, 12 figures, submitted to AAS Journal
Regulation of mammary gland branching morphogenesis by the extracellular matrix and its remodeling enzymes.
A considerable body of research indicates that mammary gland branching morphogenesis is dependent, in part, on the extracellular matrix (ECM), ECM-receptors, such as integrins and other ECM receptors, and ECM-degrading enzymes, including matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs). There is some evidence that these ECM cues affect one or more of the following processes: cell survival, polarity, proliferation, differentiation, adhesion, and migration. Both three-dimensional culture models and genetic manipulations of the mouse mammary gland have been used to study the signaling pathways that affect these processes. However, the precise mechanisms of ECM-directed mammary morphogenesis are not well understood. Mammary morphogenesis involves epithelial 'invasion' of adipose tissue, a process akin to invasion by breast cancer cells, although the former is a highly regulated developmental process. How these morphogenic pathways are integrated in the normal gland and how they become dysregulated and subverted in the progression of breast cancer also remain largely unanswered questions
Just a wind-up? Ethnicity, religion and prejudice in Scottish football-related comedy
This article probes how media representations of football in Scotland sustain the hegemonic ideologies associated with ethnicity and religion. The paper probes the football-related comedy output of one radio programme; radio output and football comedy are both neglected cultural material in studies of sport in Scotland. It argues that ambiguity and allusive language in comedy construct multiple interpretative possibilities that can demean the social and cultural identity of particular groups in society. The discussion analyses specific sketches from the Scottish radio comedy show Watson's Wind Up. It is concluded that although humorous, these sketches reveal how ideas, myths and stereotypes that coalesce round Celtic FC and the Irish-descended and Catholic communities in Scotland reinforce and sustain anti-Irish and anti-Catholic bigotry
International Financial Reporting Standards and Earnings Quality: The Myth of Voluntary vs. Mandatory Adoption
We revisit evidence whether incentives or IFRS drive earnings quality changes, analyzing a large sample of German firms in the period from 1998 to 2008. Consistent with previous studies we find that voluntary and mandatory adopters differ distinctively in terms of essential firm characteristics and that size, leverage, age, bank ownership and ownership concentration influenced the decision to voluntarily adopt IFRS. However, regardless of the decision to voluntarily adopt IFRS, we find that conditional conservatism increased under IFRS for both groups of adopters, while evidence does not suggest an increase in value relevance under IFRS. Results on earnings management in the post-adoption period are mixed. While income smoothing decreases for voluntary but not for mandatory adopters, discretionary accruals only decrease for mandatory but not for voluntary adopters. However, further analyses suggest that the capital market environment and the economic cycle during the adoption period seem to be a more powerful explanation for this evidence than voluntary or mandatory IFRS adoption. Therefore, we conclude that incentives to voluntarily adopt IFRS did not unambiguously dominate accounting standards in determining earnings quality in the case of German firms
Integrating narratives into decision making for complex systems engineering design issues
Engineering decision making and design requires collaboration between groups from different disciplines, each with different tools, vocabulary, and concerns. Traditional engineering decision-making tools are generally based on understanding the decision makers’ values, modeling uncertainty with probability, and selecting the alternative that maximizes utility. This rational approach to decision making may not be well understood or used by many stakeholders involved in the engineering design process. Constructing narratives, a basic means of human communication, may aid in engineering communication and comprehension and help with decision making. Narratives represent events by means of a story and usually include characters or agents who cause events and to whom events happen. This paper recommends three methods for how the use of narrative can be applied to the area of engineering decision making. These methods include connecting the decision maker to the analysis, creating narrative simulations for training decision makers, and fostering consensus in problems with multiple stakeholders. An illustrative example of designing a better cookstove for the developing world demonstrates the role that understanding narratives of various stakeholders can play for accomplishing complex systems engineering
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