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The Energy Source Of The Filaments Around The Giant Galaxy Ngc 1275, A. C. Fabian, J. S. Sanders, R. J. R. Williams, A. Lazarian, Gary J. Ferland, R. M. Johnstone 2011 Institute of Astronomy, UK

The Energy Source Of The Filaments Around The Giant Galaxy Ngc 1275, A. C. Fabian, J. S. Sanders, R. J. R. Williams, A. Lazarian, Gary J. Ferland, R. M. Johnstone

Physics and Astronomy Faculty Publications

The brightest galaxy in the nearby Perseus cluster, NGC 1275, is surrounded by a network of filaments. These were first observed through their Hα emission but are now known to have a large molecular component with a total mass approaching 1011 M of gas. The filaments are embedded in hot intracluster gas and stretch over 80 kpc. They have an unusually low excitation spectrum which is well modelled by collisional heating and ionization by secondary electrons. Here we note that the surface radiative flux from the outer filaments is close to the energy flux impacting on them from particles ...


Detection Of Optical Coronal Emission From 106-K Gas In The Core Of The Centaurus Cluster, R. E. A. Canning, A. C. Fabian, R. M. Johnstone, J. S. Sanders, C. S. Crawford, N. A. Hatch, Gary J. Ferland 2011 Institute of Astronomy, UK

Detection Of Optical Coronal Emission From 106-K Gas In The Core Of The Centaurus Cluster, R. E. A. Canning, A. C. Fabian, R. M. Johnstone, J. S. Sanders, C. S. Crawford, N. A. Hatch, Gary J. Ferland

Physics and Astronomy Faculty Publications

We report a detection (3.5 × 1037± 5.6 × 1036 erg s−1) of the optical coronal emission line [Fe X] λ6374 and upper limits of four other coronal lines using high-resolution VIMOS spectra centred on NGC 4696, the brightest cluster galaxy in the Centaurus cluster. Emission from these lines is indicative of gas at temperatures between 1 × 106−5 × 106 K, so traces the interstellar gas in NGC 4696. The rate of cooling derived from the upper limits is consistent with the cooling rate from X-ray observations (∼10 M yr−1); however, we detect twice ...


Global Properties Of ‘Ordinary’ Early-Type Galaxies: Photometry And Spectroscopy Of Stars And Globular Clusters In Ngc 4494, C. Foster, L. R. Spitler, Aaron J. Romanowsky, D. A. Forbes, V. Pota, K. Bekki, J. Strader, R. N. Proctor, J. A. Arnold, J. P. Brodie 2011 Swinburne University

Global Properties Of ‘Ordinary’ Early-Type Galaxies: Photometry And Spectroscopy Of Stars And Globular Clusters In Ngc 4494, C. Foster, L. R. Spitler, Aaron J. Romanowsky, D. A. Forbes, V. Pota, K. Bekki, J. Strader, R. N. Proctor, J. A. Arnold, J. P. Brodie

Faculty Publications

We present a comprehensive analysis of the spatial, kinematic and chemical properties of stars and globular clusters (GCs) in the ‘ordinary’ elliptical galaxy NGC 4494 using data from the Keck and Subaru telescopes. We derive galaxy surface brightness and colour profiles out to large galactocentric radii. We compare the latter to metallicities derived using the near-infrared Calcium Triplet. We obtain stellar kinematics out to ∼3.5 effective radii. The latter appear flattened or elongated beyond ∼1.8 effective radii in contrast to the relatively round photometric isophotes. In fact, NGC 4494 may be a flattened galaxy, possibly even an S0 ...


An Extremely Luminous Panchromatic Outburst From The Nucleus Of A Distant Galaxy, A. J. Levan, N. R. Tanvir, S. B. Cenko, D. A. Perley, K. Wiersema, J. S. Bloom, A. S. Fruchter, A. de Urgarte Postigo, P. T. Butler, A. J. van der Horst, G. Leloudas, A. N. Morgan, K. Misra, G. C. Bower, J. Farihi, R. L. Tunnicliffe, A. N. Morgan, K. Misra, G. C. Bower, J. Farihi, R. L. Tunnicliffe, M. Modjaz, J. M. Silverman, J. Hjorth, C. Thone, A. Cucchiara, J. M. Castro-Ceron, A. J. Castro-Tirado, J. A. Arnold, M. Bremer, J. P. Brodie, T. Carroll, M. C. Cooper, P. A. Curran, R. M. Cutri, J. Ehle, D. Forbes, J. Fynbo, J. Gorosabel, J. Graham, D. I. Hoffman, S. Guziy, P. Jakobsson, A. Kamble, T. Kerr, M. M. Kasliwal, C. Kouveliotou, D. Kocevski, N. M. Law, P. E. Nugent, E. O. Ofek, D. Poznanski, R. M. Quimby, E. Rol, Aaron J. Romanowsky, R. Sanchez-Ramirez, S. Schulze, N. Singh, L. van Spaandonk, R.L.C. Starling, R. G. Strom, J. C. Tello, O. Vaduvescu, P. J. Wheatley, J. M. Winters, R.A.M.J. Wijers, D. Xu 2011 University of Warwick

An Extremely Luminous Panchromatic Outburst From The Nucleus Of A Distant Galaxy, A. J. Levan, N. R. Tanvir, S. B. Cenko, D. A. Perley, K. Wiersema, J. S. Bloom, A. S. Fruchter, A. De Urgarte Postigo, P. T. Butler, A. J. Van Der Horst, G. Leloudas, A. N. Morgan, K. Misra, G. C. Bower, J. Farihi, R. L. Tunnicliffe, A. N. Morgan, K. Misra, G. C. Bower, J. Farihi, R. L. Tunnicliffe, M. Modjaz, J. M. Silverman, J. Hjorth, C. Thone, A. Cucchiara, J. M. Castro-Ceron, A. J. Castro-Tirado, J. A. Arnold, M. Bremer, J. P. Brodie, T. Carroll, M. C. Cooper, P. A. Curran, R. M. Cutri, J. Ehle, D. Forbes, J. Fynbo, J. Gorosabel, J. Graham, D. I. Hoffman, S. Guziy, P. Jakobsson, A. Kamble, T. Kerr, M. M. Kasliwal, C. Kouveliotou, D. Kocevski, N. M. Law, P. E. Nugent, E. O. Ofek, D. Poznanski, R. M. Quimby, E. Rol, Aaron J. Romanowsky, R. Sanchez-Ramirez, S. Schulze, N. Singh, L. Van Spaandonk, R.L.C. Starling, R. G. Strom, J. C. Tello, O. Vaduvescu, P. J. Wheatley, J. M. Winters, R.A.M.J. Wijers, D. Xu

Faculty Publications

Variable x-ray and γ-ray emission is characteristic of the most extreme physical processes in the universe. We present multiwavelength observations of a unique γ-ray–selected transient detected by the Swift satellite, accompanied by bright emission across the electromagnetic spectrum, and whose properties are unlike any previously observed source. We pinpoint the event to the center of a small, star-forming galaxy at redshift z = 0.3534. Its high-energy emission has lasted much longer than any γ-ray burst, whereas its peak luminosity was ∼100 times higher than bright active galactic nuclei. The association of the outburst with the center of its host ...


The Dark Halo Of He Hydra I Galaxy Cluster: Core, Cusp, Cosmological? Dynamics Of Ngc 3311 And Its Globular Cluster System, T. Richtler, R. Salinas, I. Misgeld, M. Hilker, G.K. T. Hau, Aaron J. Romanowsky, Y. Schuberth, M. Spolaor 2011 Universidad de Concepción

The Dark Halo Of He Hydra I Galaxy Cluster: Core, Cusp, Cosmological? Dynamics Of Ngc 3311 And Its Globular Cluster System, T. Richtler, R. Salinas, I. Misgeld, M. Hilker, G.K. T. Hau, Aaron J. Romanowsky, Y. Schuberth, M. Spolaor

Faculty Publications

Context. Some galaxy clusters exhibit shallow or even cored dark matter density profiles in their central regions rather than the predicted steep or cuspy profiles, conflicting with the standard understanding of dark matter. NGC 3311 is the central cD galaxy of the Hydra I cluster (Abell 1060). Aims. We use globular clusters around NGC 3311, combined with kinematical data of the galaxy itself, to investigate the dark matter distribution in the central region of Hydra I. Methods. Radial velocities of 118 bright globular clusters, based on VLT/VIMOS mask spectroscopy, are used to calculate velocity dispersions which are well defined ...


Caribbean Acropora Restoration Guide: Best Practices For Propagation And Population Enhancement, Meaghan E. Johnson, Caitlin Lustic, Erich Bartels, Iliana B. Baums, David S. Gilliam, Elizabeth Anne Larson, Diego Lirman, Margaret W. Miller, Ken Nedimyer, S. Schopmeyer 2011 The Nature Conservancy - Florida

Caribbean Acropora Restoration Guide: Best Practices For Propagation And Population Enhancement, Meaghan E. Johnson, Caitlin Lustic, Erich Bartels, Iliana B. Baums, David S. Gilliam, Elizabeth Anne Larson, Diego Lirman, Margaret W. Miller, Ken Nedimyer, S. Schopmeyer

Oceanography Faculty Reports

No abstract provided.


Performance Modeling Of Distributed Collaboration Services, Toqeer A. Israr, Gregor V. Bochmann 2011 Eastern Illinois University

Performance Modeling Of Distributed Collaboration Services, Toqeer A. Israr, Gregor V. Bochmann

Faculty Research & Creative Activity

This paper deals with performance modeling of distributed applications, service compositions and workflow systems. From the functional perspective, the distributed application is modeled as a collaboration involving several roles, and its behavior is defined in terms of a composition from several sub-collaborations using the standard sequencing operators found in UML Activity Diagrams and similar formalisms. For the performance perspective, each collaboration is characterized by a certain number of independent input events and dependent output events, and the performance of the collaboration is defined by the minimum delays that apply for a given output event in respect to each input event ...


A Geometric Framework For Analyzing The Performance Of Multiple-Antenna Systems Under Finite-Rate Feedback, Rajesh Tembarai Krishnamachari 2011 University of Colorado at Boulder

A Geometric Framework For Analyzing The Performance Of Multiple-Antenna Systems Under Finite-Rate Feedback, Rajesh Tembarai Krishnamachari

Electrical, Computer & Energy Engineering Graduate Theses & Dissertations

We study the performance of multiple-antenna systems under finite-rate feedback of some function of the current channel realization from a channel-aware receiver to the transmitter. Our analysis is based on a novel geometric paradigm whereby the feedback information is modeled as a source distributed over a Riemannian manifold. While the right singular vectors of the channel matrix and the subspace spanned by them are located on the traditional Stiefel and Grassmann surfaces, the optimal input covariance matrix is located on a new manifold of positive semi-definite matrices - specified by rank and trace constraints - called the Pn manifold. The geometry of ...


How Cios Overcome The Competing Values Challenge: Irish Cios’ Perspectives, Harvey Enns, Dean B. McFarlin, Paul B. Sweeney 2011 University of Dayton

How Cios Overcome The Competing Values Challenge: Irish Cios’ Perspectives, Harvey Enns, Dean B. Mcfarlin, Paul B. Sweeney

MIS/OM/DS Faculty Publications

Competing values are a fact of organizational life. However, there are gaps in our understanding about how these opposing beliefs hinder influence processes. This article draws on interview data to demonstrate how Irish Chief Information Officers (CIOs) are able to convince their colleagues to support new projects within their firms in the face of competing values. Focused interviews were used to explore the influence process and the competing values phenomenon, since this type of research is at an early stage and qualitative methods and analysis serve as a rich source of theory development.

The data showed that the CIOs who ...


Goali: A Hybrid Method To Support Natural Interaction Of Parts In A Virtual Environment, Judy M. Vance, Stephen B. Gilbert, Michael Oren, Ryan A. Pavlik, Patrick E. Carlson 2011 Iowa State University

Goali: A Hybrid Method To Support Natural Interaction Of Parts In A Virtual Environment, Judy M. Vance, Stephen B. Gilbert, Michael Oren, Ryan A. Pavlik, Patrick E. Carlson

Mechanical Engineering Conference Presentations, Papers, and Proceedings

The overall goal of this research is to improve the design of assembly methods through the use of virtual reality (VR) and haptics (force feedback). The research is focused on two critical aspects: the development of methods for simulating natural part-to-part interaction to support the human-centric approach to concurrent design and the evaluation of these methods in a manufacturing design context. As part of the research, we have developed the SPARTA software platform, explored new VR interaction methods and conducted several site visits at Deere facilities to better understand their processes and operations. This paper summarizes the efforts and results ...


Design And Development Of A Droplet Mass Spectrometer, Luis Alberto Cuadra-Rodriguez 2011 University of Colorado at Boulder

Design And Development Of A Droplet Mass Spectrometer, Luis Alberto Cuadra-Rodriguez

Chemistry & Biochemistry Graduate Theses & Dissertations

A droplet mass spectrometer has been built to study the oxidation of salt-water droplets coated by organic surfactants. These studies are to model the complex interfacial chemistry of nascent organic marine aerosols. The model predicts the aerosols to have a structure of an "inverted micelle" where a core salt-water droplet is coated by surfactants. Reactions with atmospheric oxidants are predicted to transform the hydrophobic surface to hydrophilic, making the aerosols better cloud condensation nuclei. A small review on single particle mass spectrometry details the consideration for the design and development criteria for the construction of the instrument. The design and ...


Ultrafast Optical Studies Of Multiple Exciton Generation In Lead Chalcogenide Quantum Dots, Aaron G. Midgett 2011 University of Colorado at Boulder

Ultrafast Optical Studies Of Multiple Exciton Generation In Lead Chalcogenide Quantum Dots, Aaron G. Midgett

Chemistry & Biochemistry Graduate Theses & Dissertations

Providing affordable, clean energy is one of the major challenges facing society today, and one of the promising solutions is third generation solar energy conversion. Present day, first and second-generation solar cells can at most convert each absorbed photon into a single electron hole pair, thereby establishing a theoretical limit to the power conversion efficiency. The process of multiple exciton generation (MEG) in semiconductor quantum dots increases that theoretical efficiency from 33% to 42% by utilizing the excess energy of high energy photons that is otherwise wasted as heat to excite a second electron-hole pair, thereby boosting the potential photocurrent ...


Production, Optimization And Characterization Of Pharmaceutical And Excipient Powders Produced By Carbon Dioxide-Assisted Nebulization With A Bubble Dryer (Can-Bd), David H. McAdams 2011 University of Colorado at Boulder

Production, Optimization And Characterization Of Pharmaceutical And Excipient Powders Produced By Carbon Dioxide-Assisted Nebulization With A Bubble Dryer (Can-Bd), David H. Mcadams

Chemistry & Biochemistry Graduate Theses & Dissertations

Vaccination is frequently acknowledged as the invention most beneficial to human development. In the past 50 years vaccination has advanced greatly in terms of consistency and efficacy, but, in order to improve accessibility of vaccines to underserved populations in the developing world, more research must be conducted to improve the safety of delivery, affordability and stability of vaccines. This doctoral dissertation work has centered on the production of stable, dry powder vaccines and pharmaceuticals for inhalation. A principal goal has been to prepare consistent dry powders of measles vaccine for delivery by inhalation with activity comparable to commercially available products ...


Formal Total Synthesis Of Diazonamide A, Cheng-Kang Mai 2011 University of Colorado at Boulder

Formal Total Synthesis Of Diazonamide A, Cheng-Kang Mai

Chemistry & Biochemistry Graduate Theses & Dissertations

This dissertation describes efforts toward the total synthesis of diazonamide A, a complex marine natural product. First, efficient methods to prepare 3,3-diaryloxindoles from 3-aryloxindoles were developed via either Pd-catalyzed alpha-arylations or nucleophilic aromatic substitutions using the oxindole enolate as the nucleophile. Second, this method has been successfully applied to a formal synthesis of diazonamide A via the highly diastereoselective construction of the C10 quaternary center. Third, a cyclization precursor for a cascade alpha-arylation/direct arylation approach to the total synthesis was synthesized and tested, and this substrate was found to be failed to cyclize. Finally, two approaches to the ...


Adaptive Use Of Thresholding And Multiple Colour Space Representation To Improve Classification Of Mmcc Barcode, Siong Khai Ong, Douglas Chai, Alexander Rassau 2011 Edith Cowan University

Adaptive Use Of Thresholding And Multiple Colour Space Representation To Improve Classification Of Mmcc Barcode, Siong Khai Ong, Douglas Chai, Alexander Rassau

ECU Publications 2011

Colour 2D barcodes, such as the MMCC barcode, have been developed recently to improve the data capacity of monochrome barcodes. However, the use of colour imposes greater challenges in decoding the symbols correctly as different lighting conditions on the barcode vary the values of the colours significantly. Hence, it is desirable to have an adaptive classification of the data cells so as to adapt to various lighting conditions. In this paper, we propose a classification method that is able to adapt to different lighting conditions during the classification of the MMCC data cells in a mobile environment. To highlight the ...


Initial Ablation Of The Laurentide Ice Sheet Based On Gulf Of Mexico Sediments, Elizabeth A. Brown 2011 University of South Florida

Initial Ablation Of The Laurentide Ice Sheet Based On Gulf Of Mexico Sediments, Elizabeth A. Brown

Graduate Theses and Dissertations

The objective of this project is to reconstruct a picture of initial Laurentide Ice Sheet retreat at the end of the Last Glacial Maximum (LGM) using geochemical proxies in Gulf of Mexico sediments, and place the reconstruction into global perspective. The project asks two questions. (1) Can a time frame be established for initial retreat of the Laurentide Ice Sheet? (2) If so, how does the timing compare to that of other large ice sheets and mountain glaciers in both hemispheres?

Sediment core MD02-2550 from the anoxic Orca Basin offers excellent preservation and a high sediment accumulation rate. Twelve accelerator ...


Pce Groundwater Quality Assessment Of The University Of Northern Iowa Campus Area, Brian Gedlinske 2011 University of Northern Iowa

Pce Groundwater Quality Assessment Of The University Of Northern Iowa Campus Area, Brian Gedlinske

Graduate Research Papers

Perchloroethylene (PCE), is a colorless, nonflammable, and relatively insoluble chlorinated solvent once widely used for dry cleaning and metal degreasing operations. Because of its past widespread use, poor solvent management practices, and environmental persistence, PCE is a common contaminant found in groundwater supplies. Potential health concerns include liver problems and increased cancer risk.

This research paper presents the findings of an effort to better characterize the spatial, temporal, and transport attributes of a PCE groundwater plume that exists within the Devonian aquifer underlying the University of Northern Iowa campus and the surrounding area in Cedar Falls, Iowa. Findings reveal the ...


Grazing Management Effects On Sediment, Phosphorus, And Pathogen Loading Of Streams In Cool-Season Grass Pastures, Kirk A. Schwarte, James R. Russell, John Kovar, Daniel G. Morrical, Steve Ensley, Kyoung-Jin Yoon, Nancy A. Cornick, Yong Il Cho 2011 Iowa State University

Grazing Management Effects On Sediment, Phosphorus, And Pathogen Loading Of Streams In Cool-Season Grass Pastures, Kirk A. Schwarte, James R. Russell, John Kovar, Daniel G. Morrical, Steve Ensley, Kyoung-Jin Yoon, Nancy A. Cornick, Yong Il Cho

Veterinary Microbiology and Preventive Medicine Publications

Erosion and runoff from pastures may lead to degradation of surface water. A 2-yr grazing study was conducted to quantify the effects of grazing management on sediment, phosphorus (P), and pathogen loading of streams in cool-season grass pastures. Six adjoining 12.1-ha pastures bisected by a stream in central Iowa were divided into three treatments: continuous stocking with unrestricted stream access (CSU), continuous stocking with restricted stream access (CSR), and rotational stocking (RS). Rainfall simulations on stream banks resulted in greater (P < 0.10) proportions of applied precipitation and amounts of sediment and P transported in runoff from bare sites than from vegetated sites across grazing treatments. Similar differences were observed comparing vegetated sites in CSU and RS pastures with vegetated sites in CSR pastures. Bovine enterovirus was shed by an average of 24.3% of cows during the study period and was collected in the runoff of 8.3 and 16.7% of runoff simulations on bare sites in CSU pastures in June and October of 2008, respectively, and from 8.3% of runoff simulations on vegetated sites in CSU pastures in April 2009. Fecal pathogens (bovine coronavirus [BCV], bovine rotavirus group A, andEscherichia coli O157:H7) shed or detected in runoff were almost nonexistent; only BCV was detected in feces ...


Analysis Of The Dpg Method For The Poisson Equation, Leszek Demkowicz, Jay Gopalakrishnan 2011 University of Texas at Austin

Analysis Of The Dpg Method For The Poisson Equation, Leszek Demkowicz, Jay Gopalakrishnan

Mathematics and Statistics Faculty Publications and Presentations

We give an error analysis of the recently developed DPG method applied to solve the Poisson equation and a convection-dffusion problem. We prove that the method is quasioptimal. Error estimates in terms of both the mesh size h and the polynomial degree p (for various element shapes) can be derived from our results. Results of extensive numerical experiments are also presented.


Polynomial Extension Operators. Part Iii, Leszek Demkowicz, Jay Gopalakrishnan, Joachim Schöberl 2011 University of Texas at Austin

Polynomial Extension Operators. Part Iii, Leszek Demkowicz, Jay Gopalakrishnan, Joachim Schöberl

Mathematics and Statistics Faculty Publications and Presentations

In this concluding part of a series of papers on tetrahedral polynomial extension operators, the existence of a polynomial extension operator in the Sobolev space H(div) is proven constructively. Specifically, on any tetrahedron K, given a function w on the boundary ∂K that is a polynomial on each face, the extension operator applied to w gives a vector function whose components are polynomials of at most the same degree in the tetrahedron. The vector function is an extension in the sense that the trace of its normal component on the boundary ∂K coincides with w. Furthermore, the extension operator ...


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