12,484 research outputs found
The Four Cs of Promising Practices in Community Colleges
To address the achievement or opportunity gap of underrepresented populations in community colleges, this qualitative field methods study investigated five California community college programs that have demonstrated progress in improving (or show significant potential to improve) student achievement. This research found that promising practices have several conceptual conditions in common-cohesion, connection, cooperation, and consistency-referred to as the Four Cs. Although many of the key components that contribute to the development of promising practices in community college programs are unique to their specific contexts, the presence of these more general Four Cs may be transferable to other community college sites because they can be cultivated in different contexts while respecting the idiosyncrasies of particular community colleges. © 2014 Copyright Taylor and Francis Group, LLC
Symmetry and Topological Order
We prove sufficient conditions for Topological Quantum Order at both zero and
finite temperatures. The crux of the proof hinges on the existence of
low-dimensional Gauge-Like Symmetries (that notably extend and differ from
standard local gauge symmetries) and their associated defects, thus providing a
unifying framework based on a symmetry principle. These symmetries may be
actual invariances of the system, or may emerge in the low-energy sector.
Prominent examples of Topological Quantum Order display Gauge-Like Symmetries.
New systems exhibiting such symmetries include Hamiltonians depicting
orbital-dependent spin exchange and Jahn-Teller effects in transition metal
orbital compounds, short-range frustrated Klein spin models, and p+ip
superconducting arrays. We analyze the physical consequences of Gauge-Like
Symmetries (including topological terms and charges), discuss associated
braiding, and show the insufficiency of the energy spectrum, topological
entanglement entropy, maximal string correlators, and fractionalization in
establishing Topological Quantum Order. General symmetry considerations
illustrate that not withstanding spectral gaps, thermal fluctuations may impose
restrictions on certain suggested quantum computing schemes and lead to
"thermal fragility". Our results allow us to go beyond standard topological
field theories and engineer systems with Topological Quantum Order.Comment: 10 pages, 2 figures. Minimal changes relative to published version-
most notably the above shortened title (which was too late to change upon
request in the galley proofs). An elaborate description of all of the results
in this article appeared in subsequent works, principally in
arXiv:cond-mat/0702377 which was published in the Annals of Physics 324, 977-
1057 (2009
Community College Culture and Faculty of Color
This investigation examines and explains the ways in which community college faculty of color construct their understandings of institutional culture. We investigate four community colleges in California through interviews with 31 full-time faculty of color. This faculty group expresses identity conflicts between their professional roles and their cultural identities. Their understandings of their institutions suggest that the culture of the community college is more complex and multi-faceted than that portrayed in the scholarly literature, which often portrays the institution as homogeneous and the faculty body as uniform. © The Author(s) 2013
“Dangerous Work”: Improving Conditions for Faculty of Color in the Community College
This qualitative investigation of the experiences of faculty of color at community colleges identifies current conditions for this population and suggests potentials for ameliorating conditions that inhibit their job satisfaction. We argue that the current conditions for faculty of color, based upon their expressed experiences at the community colleges, are deleterious to their professional performance, to their positive self-image, and to their contributions to their institutions. Alterations to these current conditions are unlikely without systemic institutional change. Indeed, without improvement to these conditions, the job satisfaction of faculty of color is not likely to change
The Divided Self: The Double Consciousness of Faculty of Color in Community Colleges
Through qualitative field methods research addressing faculty of color in four California community colleges, this investigation examines and explains faculty experiences and professional sense making. By combining critical race theory with social identity theory, our perspective underlines the potential social and ethnic identity conflicts inherent in the daily lives of faculty of color. The professional and social identities of faculty of color are not necessarily compatible, leading to a condition of "double consciousness," or what we refer to as "the divided self." © The Author(s) 2013
Measuring the saturation scale in nuclei
The saturation momentum seeing in the nuclear infinite momentum frame is
directly related to transverse momentum broadening of partons propagating
through the medium in the nuclear rest frame. Calculation of broadening within
the color dipole approach including the effects of saturation in the nucleus,
gives rise to an equation which describes well data on broadening in Drell-Yan
reaction and heavy quarkonium production.Comment: 11 pages, 5 figures, based on the talk presented by B.K. at the INT
workshop "Physics at a High Energy Electron Ion Collider", Seattle, October
200
Electrolytes between dielectric charged surfaces: Simulations and theory
We present a simulation method to study electrolyte solutions in a dielectric
slab geometry using a modified 3D Ewald summation. The method is fast and easy
to implement, allowing us to rapidly resum an infinite series of image charges.
In the weak coupling limit, we also develop a mean-field theory which allows us
to predict the ionic distribution between the dielectric charged plates. The
agreement between both approaches, theoretical and simulational, is very good,
validating both methods. Examples of ionic density profiles in the strong
electrostatic coupling limit are also presented. Finally, we explore the
confinement of charge asymmetric electrolytes between neutral surfaces
The effects of aerosols on precipitation and dimensions of subtropical clouds: a sensitivity study using a numerical cloud model
Numerical experiments were carried out using the Tel-Aviv University 2-D cloud model to investigate the effects of increased concentrations of Cloud Condensation Nuclei (CCN), giant CCN (GCCN) and Ice Nuclei (IN) on the development of precipitation and cloud structure in mixed-phase sub-tropical convective clouds. In order to differentiate between the contribution of the aerosols and the meteorology, all simulations were conducted with the same meteorological conditions. <P style='line-height: 20px;'> The results show that under the same meteorological conditions, polluted clouds (with high CCN concentrations) produce less precipitation than clean clouds (with low CCN concentrations), the initiation of precipitation is delayed and the lifetimes of the clouds are longer. GCCN enhance the total precipitation on the ground in polluted clouds but they have no noticeable effect on cleaner clouds. The increased rainfall due to GCCN is mainly a result of the increased graupel mass in the cloud, but it only partially offsets the decrease in rainfall due to pollution (increased CCN). The addition of more effective IN, such as mineral dust particles, reduces the total amount of precipitation on the ground. This reduction is more pronounced in clean clouds than in polluted ones. <P style='line-height: 20px;'> Polluted clouds reach higher altitudes and are wider than clean clouds and both produce wider clouds (anvils) when more IN are introduced. Since under the same vertical sounding the polluted clouds produce less rain, more water vapor is left aloft after the rain stops. In our simulations about 3.5 times more water evaporates after the rain stops from the polluted cloud as compared to the clean cloud. The implication is that much more water vapor is transported from lower levels to the mid troposphere under polluted conditions, something that should be considered in climate models
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