2,751 research outputs found
Generalized Geologic Map for Land-Use Planning: Breckinridge County, Kentucky
This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock
Complexity for Modules Over the Classical Lie Superalgebra gl(m|n)
Let be a
classical Lie superalgebra and be the category of finite
dimensional -supermodules which are completely reducible over the
reductive Lie algebra . In an earlier paper the authors
demonstrated that for any module in the rate of growth of the
minimal projective resolution (i.e., the complexity of ) is bounded by the
dimension of . In this paper we compute the complexity
of the simple modules and the Kac modules for the Lie superalgebra
. In both cases we show that the complexity is related to
the atypicality of the block containing the module.Comment: 32 page
Electrostatic fluctuations in cavities within polar liquids and thermodynamics of polar solvation
We present the results of numerical simulations of fluctuations of the
electrostatic potential and electric field inside cavities created in the fluid
of dipolar hard spheres. We found that the thermodynamics of polar solvation
dramatically changes its regime when the cavity size becomes about 4-5 times
larger than the size of the liquid particle. The range of small cavities can be
reasonably understood within the framework of current solvation models. On the
contrary, the regime of large cavities is characterized by a significant
softening of the cavity interface resulting in a decay of the fluctuation
variances with the cavity size much faster than anticipated by both the
continuum electrostatics and microscopic theories. For instance, the variance
of potential decays with the cavity size approximately as
instead of the scaling expected from standard electrostatics. Our
results suggest that cores of non-polar molecular assemblies in polar liquids
lose solvation strength much faster than is traditionally anticipated.Comment: 10 pp, 10 fig
Maine’s Food System: An Overview and Assessment
From an agrarian and seafaring past, Maine’s food system has seen profound changes over the past two centuries. Grain, milk, livestock, fish, potatoes, vegetables and fruits used to come from small, family farms. Today, most people in Maine don’t know where their food comes from. Many are dependent on federal, state and local “emergency food systems” such as food stamps, food pantries, and childhood nutrition programs. Food-processing facilities, distribution systems, and value-added products are in short supply. Nevertheless, Maine has a diversity and abundance of food products. In this article, the authors provide a historical overview and current analysis of Maine’s food system, highlighting encouraging trends and opportunities for the state
Global communication part 1: the use of apparel CAD technology
Trends needed for improved communication systems, through the development of future computer-aided design technology (CAD) applications, is a theme that has received attention due to its perceived benefits in improving global supply chain efficiencies. This article discusses the developments of both 2D and 3D computer-aided design capabilities, found within global fashion supply chain relationships and environments. Major characteristics identified within the data suggest that CAD/CAM technology appears to be improving; however, evidence also suggest a plateau effect, which is accrediting forced profits towards information technology manufactures, and arguably compromising the industry's competitive advantage. Nevertheless, 2D CAD increases communication speed; whereas 3D human interaction technology is seen to be evolving slowly and questionably with limited success. The article discusses the findings and also presents the issues regarding human interaction; technology education; and individual communication enhancements using technology processes. These are still prevalent topics for the future developments of global strategy and cultural communication amalgamation
Video recording true single-photon double-slit interference
As normally used, no commercially available camera has a low-enough dark
noise to directly produce video recordings of double-slit interference at the
photon-by-photon level, because readout noise significantly contaminates or
overwhelms the signal. In this work, noise levels are significantly reduced by
turning on the camera only when the presence of a photon has been heralded by
the arrival, at an independent detector, of a time-correlated photon produced
via parametric down-conversion. This triggering scheme provides the improvement
required for direct video imaging of Young's double-slit experiment with single
photons, allowing clarified versions of this foundational demonstration.
Further, we introduce variations on this experiment aimed at promoting
discussion of the role spatial coherence plays in such a measurement. We also
emphasize complementary aspects of single-photon measurement, where imaging
yields (transverse) position information, while diffraction yields the
transverse momentum, and highlight the roles of transverse position and
momentum correlations between down-converted photons, including examples of
"ghost" imaging and diffraction. The videos can be accessed at
http://sun.iwu.edu/~gspaldin/SinglePhotonVideos.html online.Comment: 7 pages, 8 figure
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Electrophysiological Guidance of Epidural Electrode Array Implantation over the Human Lumbosacral Spinal Cord to Enable Motor Function after Chronic Paralysis.
Epidural electrical stimulation (EES) of the spinal cord has been shown to restore function after spinal cord injury (SCI). Characterization of EES-evoked motor responses has provided a basic understanding of spinal sensorimotor network activity related to EES-enabled motor activity of the lower extremities. However, the use of EES-evoked motor responses to guide EES system implantation over the spinal cord and their relation to post-operative EES-enabled function in humans with chronic paralysis attributed to SCI has yet to be described. Herein, we describe the surgical and intraoperative electrophysiological approach used, followed by initial EES-enabled results observed in 2 human subjects with motor complete paralysis who were enrolled in a clinical trial investigating the use of EES to enable motor functions after SCI. The 16-contact electrode array was initially positioned under fluoroscopic guidance. Then, EES-evoked motor responses were recorded from select leg muscles and displayed in real time to determine electrode array proximity to spinal cord regions associated with motor activity of the lower extremities. Acceptable array positioning was determined based on achievement of selective proximal or distal leg muscle activity, as well as bilateral muscle activation. Motor response latencies were not significantly different between intraoperative recordings and post-operative recordings, indicating that array positioning remained stable. Additionally, EES enabled intentional control of step-like activity in both subjects within the first 5 days of testing. These results suggest that the use of EES-evoked motor responses may guide intraoperative positioning of epidural electrodes to target spinal cord circuitry to enable motor functions after SCI
Semi-Classical Description of Antiproton Capture on Atomic Helium
A semi-classical, many-body atomic model incorporating a momentum-dependent
Heisenberg core to stabilize atomic electrons is used to study antiproton
capture on Helium. Details of the antiproton collisions leading to eventual
capture are presented, including the energy and angular momentum states of
incident antiprotons which result in capture via single or double electron
ionization, i.e. into [He or He], and the
distribution of energy and angular momentum states following the Auger cascade.
These final states are discussed in light of recently reported, anomalously
long-lived antiproton states observed in liquid He.Comment: 15 pages, 9 figures may be obtained from authors, Revte
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Simulating a Maxwellian plasma using an electron beam ion trap
We describe a technique for producing a Maxwell–Boltzmann electron energy distribution using an electron beam ion trap (EBIT). The technique was implemented on the Lawrence Livermore EBIT to simulate Maxwellian plasmas. We discuss technical and experimental issues related to these simulations. To verify the fidelity of the quasi-Maxwellian, we have measured line emission due to dielectronic recombination (DR) and electron impact excitation (EIE) of heliumlike neon, magnesium, and argon for a range of simulated electron temperatures. The ratio of DR to EIE lines in heliumlike ions is a well understood electron temperature diagnostic. The spectroscopically inferred quasi-Maxwellian temperatures are in excellent agreement with the simulated temperatures
‘We need to get together and make ourselves heard’: everyday online spaces as incubators of political action
This article examines to what extent, and how, people engaging in political talk within ‘non-political’ discussion forums – online lifestyle communities – leads to political (or personal) action or calls-to-action. The analysis is framed in the context of wider questions of citizenship, civic engagement and political mobilization. To capture everyday political talk amongst citizens requires us to move beyond the now widely analysed online spaces of formal politics. Instead, we focus on online third spaces concerning lifestyle issues such as parenting, personal finance and popular culture. Drawing on a content analysis of three popular UK-based discussion forums over the course of five years (2010–2014), we found that (for two of the three cases) such spaces were more than just talking shops. Rather they were spaces where political actions not only emerged, but where they seemed to be cultivated. Discussions embedded in the personal lives of participants often developed – through talk – into political actions aimed at government (or other) authorities. The article sheds light on the contributing factors and processes that (potentially) trigger and foster action emerging from political talk and provides insight into the mobilization potential of third spaces
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