276 research outputs found
A Highly Flexible Bunch Compressor for the APS LEUTL FEL
The LEUTL FEL at the APS has achieved gain at 530 nm with peak beam current
\~100 A. In an effort to push to 120 nm and beyond, we have designed and are
commissioning a bunch compressor to increase the peak current to 600 A or more.
The bunch compressor uses a four-dipole chicane at an energy of 100 to 210 MeV.
To provide options for control of emittance growth due to coherent synchrotron
radiation (CSR), the chicane has variable R56. The central pair of dipoles is
movable, accommodating variable R56 with less concern about emittance dilution
from nonuniformity of the dipole field. The symmetry of the chicane is also
variable via longitudinal motion of the final dipole, which is predicted to
have an effect on emittance growth. Following the chicane, a three-screen
emittance measurement system should permit resolution of the difference in
emittance growth between various chicane configurations. A vertical bending
magnet analysis line is present to permit imaging of correlations between
transverse and energy coordinates. This paper reviews the features and expected
performance of the chicane. A companion paper discusses the physics design in
detail.
Work supported by the U.S. Department of Energy, Office of Basic Energy
Sciences, under Contract No. W-31-109-ENG-38.Comment: LINAC2000 THC05 3 pages 1 figur
Effects of neutron flux gradient and detector-vibrator geometry on the local-global responses of the UTR-10 reactor
http://www.worldcat.org/oclc/874179
Smokers\u27 Characteristics and Cluster Based Quitting Rule Discovery Model for Enhancement of Government\u27s Tobacco Control Systems
Discovery of cluster characteristics and interesting rules describing smokersâ clusters and the behavioural patterns of smokersâ quitting intentions is an important task in the development of an effective tobacco control systems. In this paper, we attempt to determine the characteristics of smokersâ clusters and simplified rule for predicting smokersâ quitting behaviour that can provide feedback to build a scientific evidence-based adaptive tobacco control systems. Standard clustering algorithm groups the data based on there inherent pattern. However, they seldom provide human understandable easy description of the clustersâ. Again, standard decision tree (SDT) based rule discovery depends on decision boundaries in the feature space. This may limit the ability of SDT to learn intermediate concepts for high dimensional large datasets such as tobacco control. In this paper, we propose a cluster-based rule discovery model (CRDM) that builds conceptual groups from which a set of decision trees (a decision forest) are constructed to find smokersâ quitting rules. We also employ a re-labelling of unsupervised cluster (RLUC) approach to determine the characteristics of the clusters. RLUC approach uses re-labelling and decision tree approach to find the characteristics of the smokersâ clusters. Experimental results on the tobacco control data set show that decision rules from the decision forest constructed by CRDM are simpler and can predict smokersâ quitting intention more accurately than a single decision tree. RLUC approach finds text-based characteristics of the smokersâ clusters which are easily understandable for policy makers in the tobacco control systems
âFixed-axisâ magnetic orientation by an amphibian: non-shoreward-directed compass orientation, misdirected homing or positioning a magnetite-based map detector in a consistent alignment relative to the magnetic field?
Experiments were carried out to investigate the earlier prediction that prolonged exposure to long-wavelength (>500 nm) light would eliminate homing orientation by male Eastern red-spotted newts Notophthalmus viridescens. As in previous experiments, controls held in outdoor tanks under natural lighting conditions and tested in a visually uniform indoor arena under full-spectrum light were homeward oriented. As predicted, however, newts held under long-wavelength light and tested under either full-spectrum or long-wavelength light (>500 nm) failed to show consistent homeward orientation. The newts also did not orient with respect to the shore directions in the outdoor tanks in which they were held prior to testing. Unexpectedly, however, the newts exhibited bimodal orientation along a more-or-less `fixed' north-northeastâsouth-southwest magnetic axis. The orientation exhibited by newts tested under full-spectrum light was indistinguishable from that of newts tested under long-wavelength light, although these two wavelength conditions have previously been shown to differentially affect both shoreward compass orientation and homing orientation. To investigate the possibility that the `fixed-axis' response of the newts was mediated by a magnetoreception mechanism involving single-domain particles of magnetite, natural remanent magnetism (NRM) was measured from a subset of the newts. The distribution of NRM alignments with respect to the headâbody axis of the newts was indistinguishable from random. Furthermore, there was no consistent relationship between the NRM of individual newts and their directional response in the overall sample. However, under full-spectrum, but not long-wavelength, light, the alignment of the NRM when the newts reached the 20 cm radius criterion circle in the indoor testing arena (estimated by adding the NRM alignment measured from each newt to its magnetic bearing) was non-randomly distributed. These findings are consistent with the earlier suggestion that homing newts use the light-dependent magnetic compass to align a magnetite-based `map detector' when obtaining the precise measurements necessary to derive map information from the magnetic field. However, aligning the putative map detector does not explain the fixed-axis response of newts tested under long-wavelength light. Preliminary evidence suggests that, in the absence of reliable directional information from the magnetic compass (caused by the 90° rotation of the response of the magnetic compass under long-wavelength light), newts may resort to a systematic sampling strategy to identify alignment(s) of the map detector that yields reliable magnetic field measurements
UA3/8/1 A Comparative Examination of University Revenues & Expenditures
Draft working paper A Comparative Examination of University Revenues & Expenditures
Waging Peace
This event serves as an exploration of non-violent approaches to resolving international conflict. Panelists and guests will discuss the sources of military conflict and explore non-violent strategies designed to promote peace. The event will examine the impact of democracy, human rights, and trade on international peace-building, explore the impact of U.N. peacekeeping, and talk about grassroots peace and anti-intervention movements,  exploring the intersections of activism and peace. Ohio State University. Mershon Center for International Security Studies.Event Web page, M4V video, event photo
The protein kinase C inhibitor, Ro-31-7459, is a potent activator of ERK and JNK MAP kinases in HUVECs and yet inhibits cyclic AMP-stimulated <i>SOCS-3</i> gene induction through inactivation of the transcription factor c-Jun
Induction of the suppressor of cytokine signalling 3 (SOCS-3) gene is vital to the normal control of inflammatory signalling. In order to understand these processes we investigated the role of the proto-oncogene component of the AP-1 transcription factor complex, c-Jun, in the regulation of SOCS-3 gene induction. We found that cyclic AMP stimulation of HUVECs promoted phosphorylation and activation of JNK MAP kinase and its substrate c-Jun. The JNK responsive element of the human SOCS-3 promoter mapped to a putative AP-1 site within 1000 bp of the transcription start site. The PKC inhibitors, GF-109203X, Gö-6983 and Ro-317549, were all found to inhibit AP-1 transcriptional activity, transcriptional activation of this minimal SOCS-3 promoter and SOCS-3 gene induction in HUVECs. Interestingly, Ro-317549 treatment was also found to promote PKC-dependent activation of ERK and JNK MAP kinases and promote JNK-dependent hyper-phosphorylation of c-Jun, whereas GF-109203X and Gö-6983 had little effect. Despite this, all three PKC inhibitors were found to be effective inhibitors of c-Jun DNA-binding activity. The JNK-dependent hyper-phosphorylation of c-Jun in response to Ro-317549 treatment of HUVECs does therefore not interfere with its ability to inhibit c-Jun activity and acts as an effective inhibitor of c-Jun-dependent SOCS-3 gene induction
Cluster based rule discovery model for enhancement of government's tobacco control strategy
Discovery of interesting rules describing the behavioural patterns of smokers' quitting intentions is an important task in the determination of an effective tobacco control strategy. In this paper, we investigate a compact and simplified rule discovery process for predicting smokers' quitting behaviour that can provide feedback to build an scientific evidence-based adaptive tobacco control policy. Standard decision tree (SDT) based rule discovery depends on decision boundaries in the feature space which are orthogonal to the axis of the feature of a particular decision node. This may limit the ability of SDT to learn intermediate concepts for high dimensional large datasets such as tobacco control. In this paper, we propose a cluster based rule discovery model (CRDM) for generation of more compact and simplified rules for the enhancement of tobacco control policy. The clusterbased approach builds conceptual groups from which a set of decision trees (a decision forest) are constructed. Experimental results on the tobacco control data set show that decision rules from the decision forest constructed by CRDM are simpler and can predict smokers' quitting intention more accurately than a single decision tree. Ă© 2010 IEEE
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