3,495 research outputs found
Criticality and superfluidity in liquid ^4He under nonequilibrium conditions
We review a striking array of recent experiments and their theoretical interpretations on the superfluid transition in ^4He in the presence of a heat flux Q. We define and evaluate a new set of critical point exponents. The statics and dynamics of the superfluid-normal interface are discussed, with special attention to the role of gravity. If Q is in the same direction as gravity, a self-organized state can arise, in which the entire sample has a uniform reduced temperature, on either the normal or superfluid side of the transition. Finally, we review recent theory and experiment regarding the heat capacity at constant Q. The excitement that surrounds this field arises from the fact that advanced thermometry and the future availability of a microgravity experimental platform aboard the International Space Station will soon open to experimental exploration decades of reduced temperature that were previously inaccessible
Time Allocations and Reward Structures for US Academic Economists from 1955–2005: Evidence from Three National Surveys
Using survey data collected in 1995, 2000 and 2005 from US academic economists, in which respondents were asked to indicate what percentage of their work time they allocate to research, teaching and service activities, and also how their departments and schools weight research, teaching and service in determining annual raises and making promotion and tenure decisions, we find these economists were allocating more time to teaching even though perceived departmental and school incentives provided a clear premium for research. The overall samples did not show major changes in their allocation of time from 1995–2005, but there were different responses at different types of schools, with increased time spent on research by faculty at doctoral schools while at masters' and baccalaureate schools more time was devoted to teaching. We use regression analysis to investigate factors that affect how different faculty members allocate their time between teaching and research. In addition to Carnegie school classifications and related school characteristics, faculty members' gender and rank were significant predictors of how economists allocate their time. Male economists, particularly among assistant professors at research universities, spent less time on teaching and more time on research than female economists.
High-speed measurement of rotational anisotropy nonlinear optical harmonic generation using position sensitive detection
We present a method of performing high-speed rotational anisotropy nonlinear
optical harmonic generation experiments at rotational frequencies of several
hertz by projecting the harmonic light reflected at different angles from a
sample onto a stationary position sensitive detector. The high rotational speed
of the technique, to times larger than existing methods, permits
precise measurements of the crystallographic and electronic symmetries of
samples by averaging over low frequency laser power, beam pointing, and pulse
width fluctuations. We demonstrate the sensitivity of our technique by
resolving the bulk four-fold rotational symmetry of GaAs about its [001] axis
using second harmonic generation
The poetic is political….and other notes on engaged scholarship
Instrumental and objectivist logics maintain a hegemonic place in Western scholarship, reasoning skills powerfully equipped to address certain dilemmas even as they may obscure other ways of knowing. In this chapter, we enlarge dominant notions of rationality by offering an aesthetic view of knowledge as vital for engaged communication scholarship. Our interest in aesthetic logics parallels concerns that have led scholars to develop feminist practices of inquiry (e.g., Harding, 1998; Hesse-Biber, 2007), interrogate the aesthetics of representations in West-centric knowledge structures from postcolonial and Subaltern Studies standpoints (e.g., Broadfoot & Munshi, 2007; Dutta, 2007, 2008), focus on autoethnographic and poetic accounts ( e.g., Carr, 2003; Ellingson, 2009), introduce reflexivity and the politics of personhood in the scholarly process ( e.g., Harding, 1991; Reinharz, 1992), and adopt narrative and dialogic understandings of knowledge constructions (e.g., Frank, 2005; Harter, 2005). Loosely coupled, these research trajectories advance alternative rationalities for witnessing and answering salient social issues. We argue for the theoretical and practical incorporation of aesthetic rationalities in engaged scholarship-logics of poss ibility that cultivate individuals \u27 capacities to imagine otherwise.
Reimagining scholarly inquiry to reflect and embrace aesthetic logics requires us to rethink our methods of data collection, analysis, and representation and our own roles as researchers and writers . When we resist the art/science dichotomy, opportunities abound for sensemaking and representation that embody aesthetic ways of knowing. Furthermore, rejection of dichotomous thinking opens up possibilities for listening to ways of knowing that lie beyond the realm of Eurocentric knowledge structures (Dutta, in press). Even after the interpretive turn, instrumental and objectivist logics often underlie and sometimes constrain the processes and products of social scientific research (Denzin & Lincoln, 2005). Traditional structures and modes of research offer important but limited conceptualizations of knowing. We can open ourselves to other ways of asking questions that include overt attention to aesthetic sensibilities . We need not reject or abandon traditional modes of research. Instead, we can enlarge the realm of possibilities for what counts as accepted research practices and advance methods for studying the aesthetic nature of communal life (Ellingson, 2009).
In this chapter, we develop an understanding of rationality that incorporates imagination, and we explore methodologies that draw on creative sensibilities. We then articul ate the salience of creativity for rendering credible previously subjugated voices, and we articulate its value for engaged communication theory and research
Assessment of fish populations and habitat on Oculina Bank, a deep-sea coral marine protected area off eastern Florida
A portion of the Oculina Bank located off eastern Florida is
a marine protected area (MPA) preserved for its dense populations of the ivory tree coral (Oculina varicosa),
which provides important habitat for fish. Surveys of fish assemblages and benthic habitat were conducted inside and outside the MPA in 2003 and 2005 by using remotely operated
vehicle video transects and digital still imagery. Fish species composition, biodiversity, and grouper densities
were used to determine whether O. varicosa forms an essential habitat compared to other structure-forming
habitats and to examine the effectiveness of the MPA. Multivariate analyses indicated no differences in fish
assemblages or biodiversity among hardbottom habitat types and grouper densities were highest among the most complex habitats; however the higher densities were not exclusive to
coral habitat. Therefore, we conclude that O. varicosa was functionally equivalent to other hardbottom habitats. Even though fish assemblages were not different among management
areas, biodiversity and grouper densities were higher inside the MPA compared to outside. The percentage of intact coral was also higher inside the MPA. These results provide initial evidence demonstrating effectiveness of the MPA for restoring reef fish and their habitat. This is the first study to compare reef fish populations on O. varicosa with other structure-forming reef habitats and also the first to examine the effectiveness of the MPA for restoring fish populations and live reef cover
The population of Iowa, its composition and changes: A brief sociological study of Iowa’s human assets
In 94 years the population of Iowa grew from 10,531 to 2,469,889.
In 1856 only 18.4 percent of the people of Iowa had been born in the state, 65.1 percent were natives of other states and 16.5 percent had come from foreign lands; while in 1925, 72.1 percent were native Iowans, 19.9 percent were natives of other states and only 8 percent were foreign born.
The settlement of Iowa took place from the east and southeast toward the west and northwest in wavelike movements. These movement gave rise to significant differences in age distribution and length of residence in the different regions of the state
The onion industry in Pleasant Valley, Iowa
The Pleasant Valley onion district in Scott county, Iowa, presents a striking example of crop specialization and intensive culture in contrast to the typical corn belt farming which prevails in this state. Approximately 500 acres are devoted exclusively to onions on a continuous crop basis, and much of the land has been devoted to this particular crop for decades. This is one of the oldest agricultural regions of the state.
In the following pages is presented a summary of a farm survey* of the onion industry of this region, including a study of the cultural practices, the problems of disease and insect control, cost of production, marketing, tenure and the seasonal distribution of labor
From Spectators of Public Affairs to Agents of Social Change: Engaging Students in the Basic Course through Service-Learning
Much literature bemoans the attitudes of Generation X (and their successors) toward civic participation (e.g., Putnam, 2000) and indeed education itself (e.g., Sacks, 1996). However, we have found students to be highly engaged when they have opportunities for active learning, such as those found in well designed service learning projects. We see this pedagogy as a small antidote to the sense of powerlessness that often pervades our culture. Drawing on diverse literatures, we explore theoretical reasons for using service-learning and illustrate its usefulness in speech communication basic course. Our discussion is organized around two key themes: (a) connection of self to subject matter, and (b) the connection of self to community. After discussing service learning exemplars in the basic course, we close with cautions about the use of service-learning
- …