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Articles 5791 - 5820 of 6763
Full-Text Articles in Physical Sciences and Mathematics
The Effects Of Histone H1 And Benzo[A] Pyrene On Chromatin Modifying Complexes., Zeina Salim Al Natour
The Effects Of Histone H1 And Benzo[A] Pyrene On Chromatin Modifying Complexes., Zeina Salim Al Natour
Theses
Packaging of DNA into the condensed structure of chromatin presents a barrier to many cellular processes that require DNA access such as transcription and replication. This problem is solved, in part, by the action of various complexes that modify the chromatin structure so that it becomes more accessible and, therefore, a more suitable platform for these processes. ATP-dependent chromatin remodeling complexes and histone acetyltransferases are examples of many chromatin modifying complexes that work to alleviate chromatin-mediated repression. Histone H1 is an important component of chromatin which serves in both stabilizing and folding of chromatin into a higher order structure. Many …
Using Computer Vision To Create A 3d Representation Of A Snooker Table For Televised Competition Broadcasting, Hao Guo, Brian Mac Namee
Using Computer Vision To Create A 3d Representation Of A Snooker Table For Televised Competition Broadcasting, Hao Guo, Brian Mac Namee
Conference papers
The Snooker Extraction and 3D Builder (SE3DB) is designed to be used as a viewer aid in televised snooker broadcasting. Using a single camera positioned over a snooker table, the system creates a virtual 3D model of the table which can be used to allow audiences view the table from any angle. This would be particularly useful in allowing viewers to determine if particular shots are possible or not. This paper will describe the design, development and evaluation of this system. Particular focus in the paper will be given to the techniques used to recognise and locate the balls on …
Synthesis, Characterization, And Spectroscopy Of Model Molybdopterin Complexes, Sharon J. Nieter Burgmayer, Mary Kim, Rebecca Petit, Amy Rothkopf, Shadia Belhamdounia, Ying Hou, Arpad Somogyi, Diana Habel-Rodriguez, Antonio Williams, Martin L. Kirk
Synthesis, Characterization, And Spectroscopy Of Model Molybdopterin Complexes, Sharon J. Nieter Burgmayer, Mary Kim, Rebecca Petit, Amy Rothkopf, Shadia Belhamdounia, Ying Hou, Arpad Somogyi, Diana Habel-Rodriguez, Antonio Williams, Martin L. Kirk
Chemistry Faculty Research and Scholarship
The preparation and characterization of new model complexes for the molybdenum cofactor are reported. The new models are distinctive for the inclusion of pterin-substituted dithiolene chelates and have the formulation Tp*MoX(pterin-R-dithiolene) (Tp* = tris(3,5,-dimethylpyrazolyl)borate), X= O, S, R= aryl or –C(OH)(CH3)2). Syntheses of Mo(4+) and (5+) complexes of two pterin-dithiolene derivatives as both oxo and sulfido compounds, and improved syntheses for pterinyl alkynes and [Et4N][Tp*MoIV(S)S4] reagents are described. Characterization methods include electrospray ionization mass spectrometry, electrochemistry, infrared spectroscopy, electron paramagnetic resonance and magnetic circular dichroism. Cyclic voltammetry reveals that the …
On Littlewood-Paley Functions, Leslie C. Cheng
On Littlewood-Paley Functions, Leslie C. Cheng
Mathematics Faculty Research and Scholarship
We prove that, for a compactly supported L-q function Phi with vanishing integral on Rn, the corresponding square function operator SF is bounded on L-p for vertical bar 1/p - 1/2 vertical bar < min{(q-1)/2, 1/2}.
Effect Of Coyotes And Release Site Selection On Survival And Movement Of Translocated Swift Foxes In The Badlands Ecosystem Of South Dakota, Greg M. Schroeder
Effect Of Coyotes And Release Site Selection On Survival And Movement Of Translocated Swift Foxes In The Badlands Ecosystem Of South Dakota, Greg M. Schroeder
Electronic Theses and Dissertations
Success of different release strategies for swift fox (Vulpes velox) translocation was evaluated in the Badlands Ecosystem in southwestern South Dakota. Release site selection (outside coyote [Canis latrans] core-use areas compared to random release sites) and release method (i.e., hard, semi-hard, and soft) were examined to determine effects on swift fox survival and movements at 50 days post-release. I hypothesized that swift foxes released outside of coyote core-use areas would survive at a higher rate than foxes released at random sites. From 2003-2006, 16 adult coyotes were fitted with Global Positioning System (GPS) radio collars and monitored during the pup …
Neutrality And Many-Valued Logics, Florentin Smarandache, Andrew Schumann
Neutrality And Many-Valued Logics, Florentin Smarandache, Andrew Schumann
Branch Mathematics and Statistics Faculty and Staff Publications
ThisbookwrittenbyA. Schumann &F. Smarandache isdevotedtoadvances of non-Archimedean multiple-validity idea and its applications to logical reasoning. Leibnitz was the first who proposed Archimedes’ axiom to be rejected. He postulated infinitesimals (infinitely small numbers) of the unit interval [0,1] which are larger than zero, but smaller than each positive real number. Robinson applied this idea into modern mathematics in [117] and developed so-called non-standard analysis. In the framework of non-standard analysis there were obtained many interesting results examined in [37], [38], [74], [117].
There exists also a different version of mathematical analysis in that Archimedes’ axiom is rejected, namely, p-adic analysis (e.g., …
Hadron Models And Related New Energy Issues, Florentin Smarandache
Hadron Models And Related New Energy Issues, Florentin Smarandache
Branch Mathematics and Statistics Faculty and Staff Publications
The present book covers a wide-range of issues from alternative hadron models to their likely implications in New Energy research, including alternative interpretation of lowenergy reaction (coldfusion) phenomena. The authors explored some new approaches to describe novel phenomena in particle physics. M Pitkanen introduces his nuclear string hypothesis derived from his Topological Geometrodynamics theory, while E. Goldfain discusses a number of nonlinear dynamics methods, including bifurcation, pattern formation (complex GinzburgLandau equation) to describe elementary particle masses. Fu Yuhua discusses a plausible method for prediction of phenomena related to New Energy development. F. Smarandache discusses his unmatter hypothesis, and A. Yefremov …
Boron Carbide Filled Neutron Shielding Textile Polymers, Derrick Anthony Manzlak
Boron Carbide Filled Neutron Shielding Textile Polymers, Derrick Anthony Manzlak
Dissertations, Theses, and Masters Projects
No abstract provided.
Tweakable Blockciphers Secure Against Generic Exponential Attacks, Elizabeth Ann Crump
Tweakable Blockciphers Secure Against Generic Exponential Attacks, Elizabeth Ann Crump
Dissertations, Theses, and Masters Projects
No abstract provided.
Paleoceanography Of The Gulf Of Papua Using Multiple Geophysical And Micropaleontological Proxies, Lawrence A. Febo
Paleoceanography Of The Gulf Of Papua Using Multiple Geophysical And Micropaleontological Proxies, Lawrence A. Febo
LSU Doctoral Dissertations
Recent marine and late Pleistocene sediments examined from the Gulf of Papua (GoP), Papua New Guinea investigate the flux and fate of detrital sediments and organic carbon over the last glacial-interglacial cycle. Based on surface sediment magnetic susceptibility (MS) and calcium carbonate concentrations, recent marine sediment is exported off the narrow shelf and into deeper regions via the Kerema Canyon of the northern Pandora Trough. Detrital clastic sediment is then dispersed deeper into the central and southern Pandora Trough. Except for pelagic deposition, very little detrital material reaches the Ashmore Trough and Eastern Plateau adjacent to the Great Barrier Reef. …
A Hike Through A Post-Ejb J2ee Web Application Architecture, Part Iii,, Konstantin Laufer, George K. Thiruvathukal, Benjamin Gonzalez
A Hike Through A Post-Ejb J2ee Web Application Architecture, Part Iii,, Konstantin Laufer, George K. Thiruvathukal, Benjamin Gonzalez
Computer Science: Faculty Publications and Other Works
By incorporating automated component, integration, and acceptance testing into the various tiers of a lightweight lava 2 Enterprise Edition (J2EE) Web application architecture, developers can shorten the development cycle and increase the quality of their work.
Cryptanalysis Of Sigaba, Wing Chan
Cryptanalysis Of Sigaba, Wing Chan
Master's Projects
SIGABA is a World War II cipher machine used by the United States. Both the United States Army and the United States Navy used it for tactical communication. In this paper, we consider an attack on SIGABA using the largest practical keyspace for the machine. This attack will highlight the strengths and weaknesses of the machine, as well as provide an insight into the strength of the security provided by the cipher.
Securing Wireless Networks From Arp Cache Poisoning, Roney Philip
Securing Wireless Networks From Arp Cache Poisoning, Roney Philip
Master's Projects
Wireless networks have become an integral part of today’s networks. The ease of deployment, low cost, mobility and high data rates have contributed significantly to their popularity. The medium of data transmission in wireless networks makes them inherently less secure than wired networks. For wireless networks to access the Internet they must be connected to a wired network via an Access Point or a wireless router. This has led wireless network equipment manufacturers to implement wireless Access Points and wireless routers with a built in switch for wired clients and a WiFi access point for wireless clients. The set up …
Concept Analysis In Web Documents, Rajesh Singh
Concept Analysis In Web Documents, Rajesh Singh
Master's Projects
A Keyword within a text/web document represents some human thought. The interaction of keywords leads to narrowing of scope of human thought by forming a more precise semantic entity called concepts. Analyzing a set of document not only requires analysis of the keywords within those documents but also their interactions within a document. In this new approach a set of documents can be analyzed where by the interactions of its keywords is also considered in finding the important concepts. These concepts can be used to cluster them into smaller subsets such that documents in each cluster will be semantically similar.
A Differential Power Analysis Resistant Randomized Algorithm Using Multiple Aes Ciphers, Richard Tran
A Differential Power Analysis Resistant Randomized Algorithm Using Multiple Aes Ciphers, Richard Tran
Master's Projects
Differential power analysis (DPA) side channel attacks have been shown to have great effectiveness in breaking ciphers (such as the Advanced Encryption Standard or AES) that were previously though to be unbreakable. There are currently many methods published that prevent differential power analysis on AES. The method proposed for this project is based on the increased usage of multiprocessors and multicore processors. By using multiple copies of the same AES cipher, a randomly chosen cipher is used to encrypt each plaintext. The other ciphers are then used to obfuscate the data made available to the attacker for DPA in the …
A Hierarchical Trusted Third-Party System For Secure Peer-To-Peer Transactions, Khoi Nguyen
A Hierarchical Trusted Third-Party System For Secure Peer-To-Peer Transactions, Khoi Nguyen
Master's Projects
A peer-to-peer (P2P) network is a distributed network of peer computers loosely connected through the Internet. Transactions in a P2P network are often conducted on a no-security basis. Moreover, peer anonymity is often highly desirable, which makes security even more difficult to achieve. In most cases, a peer executes a transaction solely based on the faith that the other peer plays by the rules. Here we propose a hierarchical Trusted Third-Party (TTP) system that facilitates secure transactions between peers in an existing P2P network. This system is designed to provide mutual authentication by using public key cryptography for peers to …
Plasma Treatment Of Bulk Nb Surface In The Ar/Cl2 Discharge, M. Rašković, L. Vuskovic, S. Popovic, A.-M. Valente-Feliciano, L. Phillips
Plasma Treatment Of Bulk Nb Surface In The Ar/Cl2 Discharge, M. Rašković, L. Vuskovic, S. Popovic, A.-M. Valente-Feliciano, L. Phillips
Physics Faculty Publications
The preparation of the cavity walls has been one of the major challenges in the superconducting radio-frequency (SRF) accelerator technology. Therefore, constant research and development effort is devoted to develop surface preparation processes that will improve roughness and lower the level of impurities, like hydrogen or oxygen, embedded in bulk Nb, having in the same time reasonable etching rates. Plasma based surface modification provides an excellent opportunity to achieve these goals. We present Ar/Cl2 discharge treatment of bulk Nb where we achieved etching rates comparable to the rates obtained with the electropolishing method without introducing impurities in Nb. The …
Quark-Hadron Duality In Spin Structure Functions G(1)(P) And G(1)(D), P. E. Bosted, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, S. E. Kuhn, Y. Prok, G. Adams, M. Amarian, P. Ambrozewicz, M. Anghinolfi, H. Bagdasaryan, M. Bektasoglu, S. Bültmann, S. L. Careccia, G. Gavalian, N. Guler, C. E. Hyde-Wright, H. G. Juengst, A. Klein, J. Lachniet, R. A. Niyazov, L. M. Qin, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Yun, J. Zhang
Quark-Hadron Duality In Spin Structure Functions G(1)(P) And G(1)(D), P. E. Bosted, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, S. E. Kuhn, Y. Prok, G. Adams, M. Amarian, P. Ambrozewicz, M. Anghinolfi, H. Bagdasaryan, M. Bektasoglu, S. Bültmann, S. L. Careccia, G. Gavalian, N. Guler, C. E. Hyde-Wright, H. G. Juengst, A. Klein, J. Lachniet, R. A. Niyazov, L. M. Qin, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Yun, J. Zhang
Physics Faculty Publications
New measurements of the spin structure functions of the proton and deuteron g(1)(p)(x,Q2) and g(1)(d)(x,Q2) in the nucleon resonance region are compared with extrapolations of target-mass-corrected next-to-leading-order (NLO) QCD fits to higher energy data. Averaged over the entire resonance region (W <2 >GeV), the data and QCD fits are in good agreement in both magnitude and Q2 dependence for Q2 >1.7 GeV2/c2. This "global" duality appears to result from cancellations among the prominent "local" resonance regions: in particular strong σ …2>
Lipschitz Continuity And Gateaux Differentiability Of The Best Approximation Operator In Vector-Valued Chebyshev Approximation, Martin Bartelt, John Swetits
Lipschitz Continuity And Gateaux Differentiability Of The Best Approximation Operator In Vector-Valued Chebyshev Approximation, Martin Bartelt, John Swetits
Mathematics & Statistics Faculty Publications
When G is a finite-dimensional Haar subspace of C ( X, Rk), the vector-valued functions (including complex-valued functions when k is 2) frorn a finite set X to Euclidean k-dimensional space, it is well-known that at any function f in C ( X, Rk) the best approximation operator satisfies the Strong Unicity condition of order 2 and a Lipschitz (Holder) condition of order 1/2. This note shows that in fact the best approximation operator satisfies the usual Lipschitz condition of order 1 and has a Gateaux derivative on a dense set of functions in C …
Optimising The Ratio Of Horseradish Peroxidase And Glucose Oxidase On A Bienzyme Electrode: Comparison Of A Theoretical And Experimental Approach, Dana Mackey, Anthony Killard, Adriano Ambrosi, Malcolm Smyth
Optimising The Ratio Of Horseradish Peroxidase And Glucose Oxidase On A Bienzyme Electrode: Comparison Of A Theoretical And Experimental Approach, Dana Mackey, Anthony Killard, Adriano Ambrosi, Malcolm Smyth
Articles
This study compares the behaviour of an electrochemical enzyme biosensor with a theoretical analysis based on a mathematical model and numerical simulation. The biosensor is based on a bi-enzyme channelling configuration, employing the enzymes glucose oxidase and horseradish peroxidase, with direct electron transfer of horseradish peroxidase at a conducting polymer electrode. This was modelled by a system of partial differential equations and boundary conditions representing convective and diffusive transport of the substrates glucose and hydrogen peroxide, as well as reaction kinetics of the bienzyme electrode. The main parameter investigated was the ratio of the two immobilised enzymes, with the aim …
The Importance Of Maine For Ecoregional Conservation Planning, Robert F. Baldwin, Stephen C. Trombulak, Karen Beazley, Conrad Reining, Gillian Woolmer, John R. Nordgren, Mark Anderson
The Importance Of Maine For Ecoregional Conservation Planning, Robert F. Baldwin, Stephen C. Trombulak, Karen Beazley, Conrad Reining, Gillian Woolmer, John R. Nordgren, Mark Anderson
Maine Policy Review
Ecoregional conservation planning aims at protecting biodiversity within a realistic social and economic framework. The authors of this article suggest that Maine’s forests are the ecological core of the entire Northern Appalachian/Acadian ecoregion, which spans four states and five Canadian provinces. Using mapping and mathematical models of the “human footprint,” they note that Maine has a large, contiguous, undeveloped and unfragmented forest compared with neighboring states and provinces. However, compared with its neighbors Maine also has the largest proportion of unprotected forest. The authors conclude with the hope that land use policy and planning can be better informed through the …
Frequency Based Incremental Attribute Selection For Gre., John D. Kelleher
Frequency Based Incremental Attribute Selection For Gre., John D. Kelleher
Conference papers
The DIT system uses an incremental greedy search to generate descriptions, similar to the incremental algorithm described in (Dale and Reiter, 1995). The selection of the next attribute to be tested for inclusion in the description is ordered by the absolute frequency of each attribute in the training corpus. Attributes are selected in descending order of frequency (i.e. the attribute that occurred most frequently in the training corpus is selected first). Where two or more attributes have the same frequency of occurrence the first attribute found with that frequency is selected. The type attribute is always included in the description. …
Electrowetting At The Nanoscale, C. D. Daub, D. Bratko, K. Leung, A. Luzar
Electrowetting At The Nanoscale, C. D. Daub, D. Bratko, K. Leung, A. Luzar
Chemistry Publications
Using molecular simulations of nano-sized aqueous droplets on a model graphite surface we demonstrate remarkable sensitivity of water contact angles to the applied electric field polarity and direction relative to the liquid/solid interface. The effect is explained by analyzing the influence of the field on interfacial hydrogen bonding in the nanodrop, which in turn affects the interfacial tensions. The observed anisotropy in droplet wetting is a new nanoscale phenomenon that has so far been elusive as, in current experimental setups, surface molecules represent a very low fraction of the total number affected by the field. Our findings may have important …
Ab Initio Study Of Electronic And Magnetic Properties Of The C-Codoped Ga1−Xmnxn (101¯0) Surface, Q. Wang, Q. Sun, Puru Jena
Ab Initio Study Of Electronic And Magnetic Properties Of The C-Codoped Ga1−Xmnxn (101¯0) Surface, Q. Wang, Q. Sun, Puru Jena
Physics Publications
First principles calculations based on gradient corrected density functional theory have been carried out to study the magnetic coupling between Mn atoms in pure and carbon doped Ga1−xMnxN thin films. We show that the ground state of Mn-doped GaN (101¯0) thin film, with Mn replacing the Ga sites, is antiferromagnetic but becomes ferromagnetic when it is codoped with C. The interaction between the Mn spins via the delocalized holes introduced by codoping of C at N sites is responsible for this transition. The overlap between Mn 3d and C 2p in the spin-up band renders half-metallic character to the C …
Magnetic Endohedral Metallofullerenes With Floppy Interiors, Meichun Qian, Stephen V. Ong, Shiv N. Khanna, Mark B. Knickelbein
Magnetic Endohedral Metallofullerenes With Floppy Interiors, Meichun Qian, Stephen V. Ong, Shiv N. Khanna, Mark B. Knickelbein
Physics Publications
It is shown that Gd3N@C80 is a highly magnetic and very stable motif that allows enhanced contrast magnetic resonance imaging and electric dipole moment with potential for cancer treatment. Using a synergistic approach combining Stern-Gerlach experiments in beams and first-principles electronic structure studies, it is demonstrated that an isolated Gd3N has a ground state spin moment of 23μBfollowed by a noncollinear state of 17.2μB only 88meV above the ground state. The large moment is largely due to localized f electrons. As a Gd3N is embedded inside a C80 cage, the localized felectrons maintain the magnetic character while the hybridization between …
Local Electronic And Optical Behaviors Of A-Plane Gan Grown Via Epitaxial Lateral Overgrowth, J. C. Moore, V. Kasliwal, A. A. Baski, X. Ni, Ü. Özgür, Hadis Morkoç
Local Electronic And Optical Behaviors Of A-Plane Gan Grown Via Epitaxial Lateral Overgrowth, J. C. Moore, V. Kasliwal, A. A. Baski, X. Ni, Ü. Özgür, Hadis Morkoç
Physics Publications
Conductive atomic force microscopy and near-field optical microscopy (NSOM) were used to study the morphology, conduction, and optical properties of a-plane GaNfilmsgrown via epitaxial lateral overgrowth (ELO) by metal organic chemical vapor deposition. The AFM images for the coalesced ELOfilms show undulations, where the window regions appear as depressions with a high density of surface pits. At reverse bias below 12V, very low uniform conduction (2pA) is seen in the window regions. Above 20V, a lower-quality sample shows localized sites inside the window regions with significant leakage, indicating a correlation between the presence of surface pits and leakage sites. Room …
Theoretical Study Of Deep-Defect States In Bulk Pbte And In Thin Films, Khang Hoang, S. D. Mahanti, Puru Jena
Theoretical Study Of Deep-Defect States In Bulk Pbte And In Thin Films, Khang Hoang, S. D. Mahanti, Puru Jena
Physics Publications
The nature of neutral defect states in PbTe, a narrow band-gap semiconductor, has been studied using density functional theory and supercell models. We find that the defect states associated with different substitutional impurities and native point defects found in bulk PbTe are preserved in the film geometry, but get modified as one goes from the surface to the subsurface layers and then to the bulklike layers. These modifications, which usually occur in the neighborhood of the band gap, will impact the transport properties of the films. Energetic studies of different impurities and native defects embedded in bulk PbTe and in …
Dehydrogenation From 3d-Transition-Metal-Doped Naalh4: Prediction Of Catalysts, A. Blomqvist, C. Moysés Araújo, Puru Jena, R. Ahuja
Dehydrogenation From 3d-Transition-Metal-Doped Naalh4: Prediction Of Catalysts, A. Blomqvist, C. Moysés Araújo, Puru Jena, R. Ahuja
Physics Publications
A fundamental understanding of the role of catalysts in improving the kinetics and thermodynamics of hydrogen sorption in NaAlH4 is the key for using this material in hydrogen storage. The authors present a systematic theoretical study of energies needed to desorb hydrogen in 3dtransition metal (Sc–Cu)-doped NaAlH4. They show that Cr and Fe atoms can be far more effective catalysts than Ti in desorbing hydrogen. The role of the 3d metal atoms in improving the thermodynamics of dehydrogenation is attributed to a significant shortening of the bond length with neighboring Al atoms.
First-Principles Study Of Magnetic Properties In V-Doped Zno, Qian Wang, Qiang Sun, Puru Jena, Zheng Hu, R. Note, Y. Kawazoe
First-Principles Study Of Magnetic Properties In V-Doped Zno, Qian Wang, Qiang Sun, Puru Jena, Zheng Hu, R. Note, Y. Kawazoe
Physics Publications
A comprehensive theoretical study of electronic and magnetic properties of V-doped ZnO in bulk as well as (112¯0)thin films has been performed using density functional theory. Vanadium atoms substituted at Zn sites show very little selectivity of site occupancy. More importantly, different geometries with ferromagnetic, ferrimagnetic, and antiferromagnetic configurations are found to be energetically nearly degenerate both in Zn1−xVxO bulk and subsurface layers of the thin film. On the other hand, V atoms couple ferromagnetically when they occupy surface sites of the thin film. The diverse magnetic behaviors in V-doped ZnO account for the many reported conflicting experimental results.
On The Structural And Energetic Properties Of The Hydrogen Absorber Li2mg(Nh)2, C. Moysés Araújo, Ralph H. Scheicher, Puru Jena, Rajeev Ahuja
On The Structural And Energetic Properties Of The Hydrogen Absorber Li2mg(Nh)2, C. Moysés Araújo, Ralph H. Scheicher, Puru Jena, Rajeev Ahuja
Physics Publications
The authors have performed density functional theory based calculations of several possible conformations for the crystal structure of Li2Mg(NH)2 and they confirm the α phase, resolved from both x-ray and neutron diffraction data, as the ground-state configuration. It is also found that although the N–H bond is stronger in Li2Mg(NH)2 than in Li2NH, hydrogen release from Li2Mg(NH)2/LiH mixture displays more favorable thermodynamics than that from the Li2NH∕LiH mixture. The insights gained from this seemingly counterintuitive result should prove helpful in the search for promising hydrogen storage materials.