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Articles 145981 - 146010 of 302581

Full-Text Articles in Physical Sciences and Mathematics

3d Fe2(Moo4)3 Microspheres With Nanosheet Constituents As High-Capacity Anode Materials For Lithium-Ion Batteries, Hao Zheng, Shiqiang Wang, Jiazhao Wang, Jun Wang, Lin Li, Yun Yang, Chuanqi Feng, Ziqi Sun Jan 2015

3d Fe2(Moo4)3 Microspheres With Nanosheet Constituents As High-Capacity Anode Materials For Lithium-Ion Batteries, Hao Zheng, Shiqiang Wang, Jiazhao Wang, Jun Wang, Lin Li, Yun Yang, Chuanqi Feng, Ziqi Sun

Australian Institute for Innovative Materials - Papers

Three-dimensional (3D) Fe2(MoO4)3 microspheres with ultrathin nanosheet constituents are first synthesized as anode materials for the lithium-ion battery. It is interesting that the single-crystalline nanosheets allow rapid electron/ion transport on the inside, and the high porosity ensures fast diffusion of liquid electrolyte in energy storage applications. The electrochemical properties of Fe2(MoO4)3 as anode demonstrates that 3D Fe2(MoO4)3 microspheres deliver an initial capacity of 1855 mAh/g at a current density of 100 mA/g. Particularly, when the current density is increased to 800 mA/g, the reversible capacity of Fe2(MoO4)3 anode still arrived at 456 mAh/g over 50 cycles. The large and reversible …

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A Facile Approach For Fabrication Of Mechanically Strong Graphene/Polypyrrole Films With Large Areal Capacitance For Supercapacitor Applications, Yu Ge, Caiyun Wang, Kewei Shu, Chen Zhao, Xiaoteng Jia, Sanjeev Gambhir, Gordon G. Wallace Jan 2015

A Facile Approach For Fabrication Of Mechanically Strong Graphene/Polypyrrole Films With Large Areal Capacitance For Supercapacitor Applications, Yu Ge, Caiyun Wang, Kewei Shu, Chen Zhao, Xiaoteng Jia, Sanjeev Gambhir, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Substantial progress has been made in free-standing flexible graphene-based films for flexible supercapacitors. However, there are limited reports on the areal capacitance of these electrodes, which is an important parameter for practical applications, especially in miniaturized electronic devices. Herein we report the facile fabrication of robust flexible graphene/polypyrrole nanoparticle films. PPy NPs act as the "spacer" between graphene layers creating hierarchical structures. This free-standing film shows excellent mechanical properties with a fracture strength of 16.89 MPa and Young's modulus of 11.77 MPa. The resulting film electrode delivers a large areal specific capacitance of 216 mF cm−2, which is higher or …

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One Dimensional Graphitic Carbon Nitrides As Effective Metal-Free Oxygen Reduction Catalysts, Muhammad Nawaz Tahir, Nasir Mahmood, Jinghan Zhu, Asif Mahmood, Faheem K. Butt, Syed Rizwan, Imran Aslam, M Tanveer, Faryal Idrees, Imran Shakir, Chuanbao Cao, Yanglong Hou Jan 2015

One Dimensional Graphitic Carbon Nitrides As Effective Metal-Free Oxygen Reduction Catalysts, Muhammad Nawaz Tahir, Nasir Mahmood, Jinghan Zhu, Asif Mahmood, Faheem K. Butt, Syed Rizwan, Imran Aslam, M Tanveer, Faryal Idrees, Imran Shakir, Chuanbao Cao, Yanglong Hou

Australian Institute for Innovative Materials - Papers

To explore the effect of morphology on catalytic properties of graphitic carbon nitride (GCN), we have studied oxygen reduction reaction (ORR) performance of two different morphologies of GCN in alkaline media. Among both, tubular GCN react with dissolved oxygen in the ORR with an onset potential close to commercial Pt/C. Furthermore, the higher stability and excellent methanol tolerance of tubular GCN compared to Pt/C emphasizes its suitability for fuel cells.

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Crystalline Tio2@C Nanosheet Anode With Enhanced Rate Capability For Lithium-Ion Batteries, Fan Yang, Yuxuan Zhu, Xiu Li, Chao Lai, Wei Guo, Jianmin Ma Jan 2015

Crystalline Tio2@C Nanosheet Anode With Enhanced Rate Capability For Lithium-Ion Batteries, Fan Yang, Yuxuan Zhu, Xiu Li, Chao Lai, Wei Guo, Jianmin Ma

Australian Institute for Innovative Materials - Papers

TiO2@C nanosheets have been obtained by a facile solvothermal method using titanate butoxide and hydrofluoric acid as precursors, followed by our novel carbon coating technique using oleic acid as the carbon source. The TiO2@C nanosheet anode shows a high discharge capacity of 145.8 mA h g-1 after 50 cycles and excellent rate capability.

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Electroactive Biocompatible Materials For Nerve Cell Stimulation, Mei Yang, Youlong Liang, Qingyuan Gui, Jun Chen, Yong Liu Jan 2015

Electroactive Biocompatible Materials For Nerve Cell Stimulation, Mei Yang, Youlong Liang, Qingyuan Gui, Jun Chen, Yong Liu

Australian Institute for Innovative Materials - Papers

In the past decades, great efforts have been developed for neurobiologists and neurologists to restore nervous system functions. Recently much attention has been paid to electrical stimulation (ES) of the nervous system as a potential way to repair it. Various conductive biocompatible materials with good electrical conductivity, biocompatibility, and long-term ES or electrical stability have been developed as the substrates for ES. In this review, we summarized different types of materials developed in the purpose for ES of nervous system, including conducting polymers, carbon nanomaterials and composites from conducting polymer/carbon nanomaterials. The present review will give our perspective on the …

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Electro-Oxidation And Reduction Of H2 On Platinum Studied By Scanning Electrochemical Microscopy For The Purpose Of Local Detection Of H2 Evolution, Seyed S. Jamali, Simon E. Moulton, Dennis E. Tallman, Jan Weber, Gordon G. Wallace Jan 2015

Electro-Oxidation And Reduction Of H2 On Platinum Studied By Scanning Electrochemical Microscopy For The Purpose Of Local Detection Of H2 Evolution, Seyed S. Jamali, Simon E. Moulton, Dennis E. Tallman, Jan Weber, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Electrochemical detection of H-2 using scanning electrochemical microscopy (SECM) has shown to hold great promise as a sensitive characterization method with high spatial resolution for active surfaces generating H-2. Herein, the factors contributing to the current that is measured by SECM in generation/collection mode for H-2 detection are studied. In particular, the concentration gradient of H-2 at the substrate, the H-2/H+ recycling between the SECM tip and substrate and hemispherical profile of H-2 diffusion has been discussed. It was postulated that H-2/H+ recycling plays a dominant role in the oxidative current measured in generation/collection mode of SECM when the microelectrode …

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Synthesis Of Nitrogen-Doped Graphene Via Thermal Treatment Of Graphene Oxide Within Methylimidazole And Its Capacitance Performance As Electric Double Layer Capacitor, Md. Monirul Islam, Shaikh Nayeem Faisal, Anup Kumar Roy, Sonia Ansari, Dean Cardillo, Konstantin K. Konstantinov, Enamul Haque Jan 2015

Synthesis Of Nitrogen-Doped Graphene Via Thermal Treatment Of Graphene Oxide Within Methylimidazole And Its Capacitance Performance As Electric Double Layer Capacitor, Md. Monirul Islam, Shaikh Nayeem Faisal, Anup Kumar Roy, Sonia Ansari, Dean Cardillo, Konstantin K. Konstantinov, Enamul Haque

Australian Institute for Innovative Materials - Papers

Nitrogen-doped graphene was successfully synthesised from graphene oxide (GO) and 2-methylimidazole composite via thermal treatment under argon flow at 700oC within 1h. This synthesised N-doped graphene exhibits homogeneous nitrogen doping with concentration of ~5% in three different nitrogen configuration namelypyridinic N, pyrrolic N and graphitic N. The electric double layer capacitor (EDLC) made up with this N-doped graphene showed excellent specific capacitance 274 F/g at current density of 1A/g, which was ~7 times higher than GO. This EDLC capacitor showed excellent cyclic stability up to 5000 cycles with capacity retention of ~91%.

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Protein Nanorings Organized By Poly(Styrene-Block-Ethylene Oxide) Self-Assembled Thin Films, Jenny Malmström, Akshita Wason, Fergus Roache, N. Amy Yewdall, Mazdak Radjainia, Shanghai Wei, Michael J. Higgins, David Williams, Juliet A. Gerrard, Jadranka Travas-Sejdic Jan 2015

Protein Nanorings Organized By Poly(Styrene-Block-Ethylene Oxide) Self-Assembled Thin Films, Jenny Malmström, Akshita Wason, Fergus Roache, N. Amy Yewdall, Mazdak Radjainia, Shanghai Wei, Michael J. Higgins, David Williams, Juliet A. Gerrard, Jadranka Travas-Sejdic

Australian Institute for Innovative Materials - Papers

This study explores the use of block copolymer self-assembly to organize Lsmα, a protein which forms stable doughnut-shaped heptameric structures. Here, we have explored the idea that 2-D crystalline arrays of protein filaments can be prepared by stacking doughnut shaped Lsmα protein into the poly(ethylene oxide) blocks of a hexagonal microphase-separated polystyrene-b-polyethylene oxide (PS-b-PEO) block copolymer. We were able to demonstrate the coordinated assembly of such a complex hierarchical nanostructure. The key to success was the choice of solvent systems and protein functionalization that achieved sufficient compatibility whilst still promoting assembly. Unambiguous characterisation of these structures is difficult; however AFM …

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Two-Dimensional Nico2o4 Nanosheet-Coated Three-Dimensional Graphene Networks For High-Rate, Long-Cycle-Life Supercapacitors, Jiang Zhou, Ying Huang, Xiehong Cao, Bo Ouyang, Wenping Sun, Chaoliang Tan, Yu Zhang, Qinglang Ma, Shuquan Liang, Qingyu Yan, Hua Zhang Jan 2015

Two-Dimensional Nico2o4 Nanosheet-Coated Three-Dimensional Graphene Networks For High-Rate, Long-Cycle-Life Supercapacitors, Jiang Zhou, Ying Huang, Xiehong Cao, Bo Ouyang, Wenping Sun, Chaoliang Tan, Yu Zhang, Qinglang Ma, Shuquan Liang, Qingyu Yan, Hua Zhang

Australian Institute for Innovative Materials - Papers

We report the synthesis of two-dimensional (2D) NiCo2O4 nanosheet-coated three-dimensional graphene network (3DGN), which is then used as an electrode for high-rate, long-cycle-life supercapacitors. Using the 3DGN and nanoporous nanosheets, an ultrahigh specific capacitance (2173 F g-1 at 6 A g-1), excellent rate capability (954 F g-1 at 200 A g-1) and superior long-term cycling performance (94% capacitance retention after 14000 cycles at 100 A g-1) are achieved.

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Spatially-Confined Lithiation-Delithiation In Highly Dense Nanocomposite Anodes Towards Advanced Lithium-Ion Batteries, Yinzhu Jiang, Yong Li, Wenping Sun, Wei Huang, Jiabin Liu, Ben Xu, Chuanhong Jin, Tianyu Ma, Changzheng Wu, Mi Yan Jan 2015

Spatially-Confined Lithiation-Delithiation In Highly Dense Nanocomposite Anodes Towards Advanced Lithium-Ion Batteries, Yinzhu Jiang, Yong Li, Wenping Sun, Wei Huang, Jiabin Liu, Ben Xu, Chuanhong Jin, Tianyu Ma, Changzheng Wu, Mi Yan

Australian Institute for Innovative Materials - Papers

Spatially-confined electrochemical reactions are firstly realized in a highly dense nanocomposite anode for high performance lithium ion batteries. The spatially-confined lithiation-delithiation effectively avoids inter-cluster migration and perfectly retains full structural integrity. Large reversible capacity, high rate capability and superior cycling stability are achieved simultaneously. This spatially-confined lithiation-delithiation offers novel insight to enhance cycling performance of high capacity anode materials.

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Surface Engineering And Design Strategy For Surface-Amorphized Tio 2 @Graphene Hybrids For High Power Li-Ion Battery Electrodes, Tengfei Zhou, Yang Zheng, Hong Gao, Shudi Min, Sean Li, Hua-Kun Liu, Zaiping Guo Jan 2015

Surface Engineering And Design Strategy For Surface-Amorphized Tio 2 @Graphene Hybrids For High Power Li-Ion Battery Electrodes, Tengfei Zhou, Yang Zheng, Hong Gao, Shudi Min, Sean Li, Hua-Kun Liu, Zaiping Guo

Australian Institute for Innovative Materials - Papers

Electrode materials with battery-like high capacity and capacitorlike rate performance are highly desirable, since they would signifi cantly advance next-generation energy storage technology. [ 1 ] TiO 2 has received increasing attention as an anode material for lithium-ion batteries (LIBs) due to its good reversible capacity and low volume expansion upon lithiation, as well as its low cost and safe lithiation potential. [ 2 ] The low lithium-ion mobility within the crystalline phase TiO 2 , however, together with its poor electrical conductivity, means that only a thin surface layer of the host material is available for Li intercalation at …

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Population Accessibility To Radiotherapy Services In New South Wales Region Of Australia: A Methodological Contribution, Nagesh Shukla, Rohan Wickramasuriya, Andrew Miller, Pascal Perez Jan 2015

Population Accessibility To Radiotherapy Services In New South Wales Region Of Australia: A Methodological Contribution, Nagesh Shukla, Rohan Wickramasuriya, Andrew Miller, Pascal Perez

SMART Infrastructure Facility - Papers

No abstract provided.

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A Stochastic And Flexible Activity Based Model For Large Population Application To Belgium, Johan Barthelemy, Philippe L. Toint Jan 2015

A Stochastic And Flexible Activity Based Model For Large Population Application To Belgium, Johan Barthelemy, Philippe L. Toint

SMART Infrastructure Facility - Papers

The VirtualBelgium project aims at developing an understanding of the evolution of the Belgian population using agent-based simulations and considering various aspects of this evolution such as demographics, residential choices, activity patterns, mobility, etc. This simulation is based on a validated synthetic population consisting of approximately 10,000,000 individuals and 4,350,000 households located in the 589 municipalities of Belgium. The work presented in this paper focuses only on the mobility behaviour of such large populations and this is simulated using an activity-based approach in which the travel demand is derived from the activities performed by the individuals. The proposed model is …

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Stepping Away From Trend Analyses For Regional Integrated Planning And Modelling, Pascal Perez, Rohan Wickramasuriya, Nam N. Huynh, Hedwig Van Delden Jan 2015

Stepping Away From Trend Analyses For Regional Integrated Planning And Modelling, Pascal Perez, Rohan Wickramasuriya, Nam N. Huynh, Hedwig Van Delden

SMART Infrastructure Facility - Papers

Strategic regional plans aim to achieve aspirational objectives such as vibrant communities,affordable transport, productive economy and protected natural environments. But planners often lack decision support tools capable of tracking complex dynamic interactions between these various components. Many current regional planning models rely on feed-forward trend analyses. These trends are based on demographic or economic assumptions that lock-in regional growth into a unique pathway. The weaker the initial assumption is, the less plausible the evolution of other components of the regional development. In fact, useful regional planning models need to reproduce the co-evolution of land use, transport, economic and demographic dynamics. …

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The Self-Adaptive Context Learning Pattern: Overview And Proposal, Jeremy Boes, Julien Nigon, Nicolas R. Verstaevel, Marie-Pierre Gleizes, Frederic Migeon Jan 2015

The Self-Adaptive Context Learning Pattern: Overview And Proposal, Jeremy Boes, Julien Nigon, Nicolas R. Verstaevel, Marie-Pierre Gleizes, Frederic Migeon

SMART Infrastructure Facility - Papers

Over the years, our research group has designed and developed many self-adaptive multi-agent systems to tackle real-world complex problems, such as robot control and heat engine optimization. A recurrent key feature of these systems is the ability to learn how to handle the context they are plunged in, in other words to map the current state of their perceptions to actions and effects. This paper presents the pattern enabling the dynamic and interactive learning of the mapping between context and actions by our multi-agent systems.

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Modeling, Optimization, And Sensitivity Analysis Of A Continuous Multi-Segment Crystallizer For Production Of Active Pharmaceutical Ingredients, Bradley James Ridder Jan 2015

Modeling, Optimization, And Sensitivity Analysis Of A Continuous Multi-Segment Crystallizer For Production Of Active Pharmaceutical Ingredients, Bradley James Ridder

Open Access Dissertations

We have investigated the simulation-based, steady-state optimization of a new type of crystallizer for the production of pharmaceuticals. The multi-segment, multi-addition plug-flow crystallizer (MSMA-PFC) offers better control over supersaturation in one dimension compared to a batch or stirred-tank crystallizer. Through use of a population balance framework, we have written the governing model equations of population balance and mass balance on the crystallizer segments. The solution of these equations was accomplished through either the method of moments or the finite volume method. The goal was to optimize the performance of the crystallizer with respect to certain quantities, such as maximizing the …

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Structure-Activity Relationships For The Water-Gas Shift Reaction Over Supported Metal Catalysts, Kaiwalya D. Sabnis Jan 2015

Structure-Activity Relationships For The Water-Gas Shift Reaction Over Supported Metal Catalysts, Kaiwalya D. Sabnis

Open Access Dissertations

The Water-Gas Shift (WGS) reaction (CO + H2O → CO2 + H2) is an important chemical process for industrial hydrogen production. The overall goal of this project is to use kinetic experiments and in situ characterization techniques in tandem, in order to derive structure-activity relationships for various catalytic systems. These relationships facilitate the rational catalyst design by identification of catalyst descriptors. In order to establish such relationships, various studies were undertaken, such as (i) effect of transition admetals on the WGS catalysis by molybdenum carbide (ii) effect of residual oxygen content on the performance of …

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Measurement Of The Drell--Yan Differential Cross Section With The Cms Detector At The Lhc, Alexey Svyatkovskiy Jan 2015

Measurement Of The Drell--Yan Differential Cross Section With The Cms Detector At The Lhc, Alexey Svyatkovskiy

Open Access Dissertations

This thesis describes precision measurements of electroweak interactions in a new energy regime and the application of these measurements to improve our understanding of the structure of the proton. The results are based on proton-proton collision data at √s = 7 and 8\TeV recorded with the Compact Muon Solenoid detector at the CERN Large Hadron Collider during the first years of operation. Measurements of the differential Drell–Yan cross section in the dimuon and dielectron channels covering the dilepton mass range of 15 to 2000\GeV and absolute dilepton rapidity from 0 to~2.4 are presented. The Drell–Yan cross section in proton-proton …

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A 2-Categorical Extension Of The Reshetikhin--Turaev Theory, Yu Tsumara Jan 2015

A 2-Categorical Extension Of The Reshetikhin--Turaev Theory, Yu Tsumara

Open Access Dissertations

We concretely construct a 2-categorically extended topological quantum field theory that extends the Reshetikhin-Turaev TQFT to cobordisms with corners. The source category will be a well chosen 2-category of decorated cobordisms with corners and the target bicategory will be the Kapranov-Voevodsky 2-vector spaces.

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Advanced Wireless Communications Using Large Numbers Of Transmit Antennas And Receive Nodes, Junil Choi Jan 2015

Advanced Wireless Communications Using Large Numbers Of Transmit Antennas And Receive Nodes, Junil Choi

Open Access Dissertations

The concept of deploying a large number of antennas at the base station, often called massive multiple-input multiple-output (MIMO), has drawn considerable interest because of its potential ability to revolutionize current wireless communication systems. Most literature on massive MIMO systems assumes time division duplexing (TDD), although frequency division duplexing (FDD) dominates current cellular systems. Due to the large number of transmit antennas at the base station, currently standardized approaches would require a large percentage of the precious downlink and uplink resources in FDD massive MIMO be used for training signal transmissions and channel state information (CSI) feedback. First, we propose …

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Instrumentation And Development Of A Mass Spectrometry System For The Study Of Gas-Phase Biomolecular Ion Reactions, Ziqing Lin Jan 2015

Instrumentation And Development Of A Mass Spectrometry System For The Study Of Gas-Phase Biomolecular Ion Reactions, Ziqing Lin

Open Access Dissertations

Gas-phase reactions of biomolecular ions are highly relevant to the understanding of structures and functions of the biomolecules. Mass spectrometry is a powerful tool in investigating gas-phase ion chemistry. Various mass spectrometers have been developed to explore ion/molecule reactions, ion/ion reactions, ion/photon reactions, ion/radical reactions etc., both at atmospheric pressure and in vacuum. In-vacuum reactions have an advantage of involving pre-selecting the ions for the reactions using a mass analyzer. Over the decades, a variety of mass analyzers have been employed in the research of ion chemistry. Hybrid configurations, such as quadrupole ion trap with a time-of-flight and or a …

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Genome-Wide Profiling Of Histone Modifications (H3k9me2 And H4k12ac) And Gene Expression In Rust (Uromyces Appendiculatus) Inoculated Common Bean (Phaseolus Vulgaris L), Vasudevan Ayyappan, Venu Kalavacharla, Jyothi Thimmapuram, Ketaki P. Bhide, Venkateswara R. Sripathi Jan 2015

Genome-Wide Profiling Of Histone Modifications (H3k9me2 And H4k12ac) And Gene Expression In Rust (Uromyces Appendiculatus) Inoculated Common Bean (Phaseolus Vulgaris L), Vasudevan Ayyappan, Venu Kalavacharla, Jyothi Thimmapuram, Ketaki P. Bhide, Venkateswara R. Sripathi

Cyber Center Publications

Histone modifications such as methylation and acetylation play a significant role in controlling gene expression in unstressed and stressed plants. Genome-wide analysis of such stress-responsive modifications and genes in non-model crops is limited. We report the genome-wide profiling of histone methylation (H3K9me2) and acetylation (H4K12ac) in common bean (Phaseolus vulgaris L.) under rust (Uromyces appendiculatus) stress using two high-throughput approaches, chromatin immunoprecipitation sequencing (ChIP-Seq) and RNA sequencing (RNA-Seq). ChIP-Seq analysis revealed 1,235 and 556 histone methylation and acetylation responsive genes from common bean leaves treated with the rust pathogen at 0, 12 and 84 hour-after-inoculation (hai), while …

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On The Origin Of Protein Superfamilies And Superfolds, Abram Magner, Wojciech Szpankowski, Daisuke Kihara Jan 2015

On The Origin Of Protein Superfamilies And Superfolds, Abram Magner, Wojciech Szpankowski, Daisuke Kihara

Department of Biological Sciences Faculty Publications

Distributions of protein families and folds in genomes are highly skewed, having a small number of prevalent superfamiles/superfolds and a large number of families/folds of a small size. Why are the distributions of protein families and folds skewed? Why are there only a limited number of protein families? Here, we employ an information theoretic approach to investigate the protein sequence-structure relationship that leads to the skewed distributions. We consider that protein sequences and folds constitute an information theoretic channel and computed the most efficient distribution of sequences that code all protein folds. The identified distributions of sequences and folds are …

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The Integration Of Heat Resources In A Solar Thermal-Heat Pump Hydronic System, John Maxfield Degrove Jan 2015

The Integration Of Heat Resources In A Solar Thermal-Heat Pump Hydronic System, John Maxfield Degrove

Open Access Theses

According to the U.S. Department of Energy, roughly 41% of the energy consumed in the U.S. is used the power buildings. Within that number, almost half is used to heat or cool the building. Current technologies allow for consistent thermal management, but most utilize energy harvested from fossil fuels or convert electricity back into thermal energy. Background literature shows that the utilization of alternative heat resources such as heat pumps and solar thermal collectors can greatly reduce the energy used for heat delivery while producing adequate heating performance. A combined hydronic system using a bank of solar thermal collectors in …

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The Antitumorigenic Function Of Egfr In Metastatic Breast Cancer Is Regulated By Expression Of Mig6, Michael Wendt, Whitney K. Williams, Pete E. Pascuzzi, Nikolas G. Balanis, Barbara J. Schiemann, Cathleen R. Carlin, William P. Schiemann Jan 2015

The Antitumorigenic Function Of Egfr In Metastatic Breast Cancer Is Regulated By Expression Of Mig6, Michael Wendt, Whitney K. Williams, Pete E. Pascuzzi, Nikolas G. Balanis, Barbara J. Schiemann, Cathleen R. Carlin, William P. Schiemann

Department of Medicinal Chemistry and Molecular Pharmacology Faculty Publications

Numerous studies by our lab and others demonstrate that epidermal growth factor receptor (EGFR) plays critical roles in primary breast cancer (BC) initiation, growth and dissemination. However, clinical trials targeting EGFR function in BC have lead to disappointing results. In the current study we sought to identify the mechanisms responsible for this disparity by investigating the function of EGFR across the continuum of the metastatic cascade. We previously established that overexpression of EGFR is sufficient for formation of in situ primary tumors by otherwise nontransformed murine mammary gland cells. Induction of epithelial-mesenchymal transition (EMT) is sufficient to drive the metastasis …

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Functional Organization And Restoration Of The Brain Motor-Execution Network After Stroke And Rehabilitation, Sahil Bajaj, Andrew Butler, Daniel Drake, Mukesh Dhamala Jan 2015

Functional Organization And Restoration Of The Brain Motor-Execution Network After Stroke And Rehabilitation, Sahil Bajaj, Andrew Butler, Daniel Drake, Mukesh Dhamala

Physics and Astronomy Faculty Publications

Multiple cortical areas of the human brain motor system interact coherently in the low frequency range (<0.1 Hz), even in the absence of explicit tasks. Following stroke, cortical interactions are functionally disturbed. How these interactions are affected and how the functional organization is regained from rehabilitative treatments as people begin to recover motor behaviors has not been systematically studied. We recorded the intrinsic functional magnetic resonance imaging (fMRI) signals from 30 participants: 17 young healthy controls and 13 aged stroke survivors. Stroke participants underwent mental practice (MP) or both mental practice and physical therapy (MP+PT) within 14–51 days following stroke. We investigated the network activity of five core areas in the motor-execution network, consisting of the left primary motor area (LM1), the right primary motor area (RM1), the left pre-motor cortex (LPMC), the right pre-motor cortex (RPMC) and the supplementary motor area (SMA). We discovered that (i) the network activity dominated in the frequency range 0.06–0.08 Hz for all the regions, and for both able-bodied and stroke participants (ii) the causal information flow between the regions: LM1 and SMA, RPMC and SMA, RPMC and LM1, SMA and RM1, SMA and LPMC, was reduced significantly for stroke survivors (iii) the flow did not increase significantly after MP alone and (iv) the flow among the regions during MP+PT increased significantly. We also found that sensation and motor scores were significantly higher and correlated with directed functional connectivity measures when the stroke-survivors underwent MP+PT but not MP alone. The findings provide evidence that a combination of mental practice and physical therapy can be an effective means of treatment for stroke survivors to recover or regain the strength of motor behaviors, and that the spectra of causal information flow can be used as a reliable biomarker for evaluating rehabilitation in stroke survivors.

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Vibrational Spectroscopy Of Photosystem I, Gary Hastings Jan 2015

Vibrational Spectroscopy Of Photosystem I, Gary Hastings

Physics and Astronomy Faculty Publications

Fourier transform infrared difference spectroscopy (FTIR DS) has beenwidely used to study the structural details of electron transfer cofactors (and their binding sites) in many types of photosynthetic protein complexes. This review focuses in particular onwork that has been done to investigate the A1 cofactor in photosystemI photosynthetic reaction centers. A reviewof this subject area last appeared in 2006 [1], so onlywork undertaken since then will be covered here. Following light excitation of intact photosystem I particles the P700+A1 \ secondary radical pair state is formed within 100 ps. This state decays within 300 ns at room temperature, or 300 …

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Understanding Mixed Sequence Dna Recognition By Novel Designed Compounds: The Kinetic And Thermodynamic Behavior Of Azabenzimidazole Diamidines, Ananya Paul, W. David Wilson, David Boykin, Yun Chai Jan 2015

Understanding Mixed Sequence Dna Recognition By Novel Designed Compounds: The Kinetic And Thermodynamic Behavior Of Azabenzimidazole Diamidines, Ananya Paul, W. David Wilson, David Boykin, Yun Chai

Chemistry Faculty Publications

Sequence-specific recognition of DNA by small organic molecules offers a potentially effective approach for the external regulation of gene expression and is an important goal in cell biochemistry. Rational design of compounds from established modules can potentially yield compounds that bind strongly and selectively with specific DNA sequences. An initial approach is to start with common A·T bp recognition molecules and build in G·C recognition units. Here we report on the DNA interaction of a synthetic compound that specifically binds to a G·C bp in the minor groove of DNA by using an azabenzimidazole moiety. The detailed interactions were evaluated …

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Efficient Chemoenzymatic Synthesis Of An N-Glycan Isomer Library, Lei Li, Yunpeng Liu, Cheng Ma, Jingyao Qu, Angie D. Calderon, Baolin Wu, Na Wei, Xuan Wang, Yuxi Guo, Zhongying Xiao, Jing Song, Go Sugiarto, Yanhong Li, Hai Yu, Xi Chen, Peng George Wang Jan 2015

Efficient Chemoenzymatic Synthesis Of An N-Glycan Isomer Library, Lei Li, Yunpeng Liu, Cheng Ma, Jingyao Qu, Angie D. Calderon, Baolin Wu, Na Wei, Xuan Wang, Yuxi Guo, Zhongying Xiao, Jing Song, Go Sugiarto, Yanhong Li, Hai Yu, Xi Chen, Peng George Wang

Chemistry Faculty Publications

Quantification, characterization and biofunctional studies of N-glycans on proteins remain challenging tasks due to the complexity, diversity and low abundance of these glycans. The availability of structurally defined N-glycan (especially isomer) libraries is essential to help solve these tasks. We report herein an efficient chemoenzymatic strategy, namely Core Synthesis/Enzymatic Extension (CSEE), for rapid production of diverse N-glycans. Starting with 5 chemically prepared building blocks, 8 N-glycan core structures containing one or two terminal N-acetyl-D-glucosamine (GlcNAc) residue(s) were chemically synthesized via consistent use of oligosaccharyl thioethers as glycosylation donors in a convergent fragment coupling strategy. Each of these core structures was …

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May The Best Molecule Win: Competition Esi Mass Spectrometry, Sarah R. Laughlin, W. David Wilson Jan 2015

May The Best Molecule Win: Competition Esi Mass Spectrometry, Sarah R. Laughlin, W. David Wilson

Chemistry Faculty Publications

Electrospray ionization mass spectrometry has become invaluable in the characterization of macromolecular biological systems such as nucleic acids and proteins. Recent advances in the field of mass spectrometry and the soft conditions characteristic of electrospray ionization allow for the investigation of non-covalent interactions among large biomolecules and ligands. Modulation of genetic processes through the use of small molecule inhibitors with the DNA minor groove is gaining attention as a potential therapeutic approach. In this review, we discuss the development of a competition method using electrospray ionization mass spectrometry to probe the interactions of multiple DNA sequences with libraries of minor …

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