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Full-Text Articles in Physical Sciences and Mathematics

An Account Of A Teacher's Perspective On Learning And Teaching Mathematics: Implications For Teacher Development, Ron Tzur, Martin Simon, Karen Heinz, Margaret Kinzel Jan 2016

An Account Of A Teacher's Perspective On Learning And Teaching Mathematics: Implications For Teacher Development, Ron Tzur, Martin Simon, Karen Heinz, Margaret Kinzel

Ron Tzur

This report presents an account of one teacher's mathematics teaching and a perspective that underlies his teaching. Nevil was a fifth grade teacher participating in current mathematics education reforms in the United States. Through the account, we make distinctions about teachers' thinking and practice that can inform teacher education efforts. We constructed an account by analyzing four sets of classroom observations and interviews. We observed that Nevil decomposed his understandings of the mathematics into smaller components and connections among those components. He created situations that he believed made those components and connections transparent and attempted to elicit those connections from …


Public-Private Partnership In Emergency And Disaster Management: Examples From The Queensland Floods 2010-2011, Bhishna Bajracharya, Peter Hastings Jan 2016

Public-Private Partnership In Emergency And Disaster Management: Examples From The Queensland Floods 2010-2011, Bhishna Bajracharya, Peter Hastings

Bhishna Bajracharya

Numerous international studies have corroborated the value of public–private sector partnerships in reducing vulnerability and building resilience to emergencies and disasters. This paper proposes a simple conceptual framework for public–private partnerships in emergency and disaster management that could be applied to research and policy analysis in Australia. The framework proposes three dimensions: sector types (public, business and community), partnership arrangements (legislated and formal to informal agreements), and partnership roles (strategic and resilience-building and response and recovery). This paper describes how the three sectors can work together under various partnership arrangements for preventive or responsive measures in emergency and disaster management. …


A Virtual Environment For Enterprise Engineering Education, Can Saygin, Benjamin Dow, Raymond Kluczny, Majdi Najm, Scott Grasman Jan 2016

A Virtual Environment For Enterprise Engineering Education, Can Saygin, Benjamin Dow, Raymond Kluczny, Majdi Najm, Scott Grasman

Dow Scott

Several resources highlight the need to effectively use modern technology to gain more productive and rewarding undergraduate science, mathematics, engineering, and technology education. In addition to the growth of information technology, the importance of hands-on practice and active learning has been highlighted in various resources. These factors, coupled with inadequate and insufficient real-world experiences in undergraduate education, have become a major reason for under-qualified and under-employed graduates. This paper discusses the creation of the University of Missouri Virtual Enterprise, which provides context for development of learning modules for enterprise engineering education. This approach will improve the undergraduate education experience by …


Enantiodiscrimination Of Methamphetamine By Circular Dichroism Using A Porphyrin Tweezer., Kerry Rouhier Jan 2016

Enantiodiscrimination Of Methamphetamine By Circular Dichroism Using A Porphyrin Tweezer., Kerry Rouhier

Kerry A Rouhier

Using exciton-coupled circular dichroism (ECCD) spectroscopy, our lab was able to differentiate between the two enantiomers of methamphetamine using a commercially available porphyrin tweezer as an achiral host. The host-guest complex formed with (+)-(S)-methamphetamine produced a negative bisignate-shaped ECCD spectrum, whereas the complex formed with (-)-(R)-methamphetamine produced a positive one. This sensitive technique could serve as an alternative method for the enantiodiscrimination of chiral methamphetamine, a commonly abused drug in the United States.


Detechip: A Sensor For Drugs Of Abuse., Kerry Rouhier Jan 2016

Detechip: A Sensor For Drugs Of Abuse., Kerry Rouhier

Kerry A Rouhier

The design and preliminary characterization of a novel sensor for drugs of abuse, DETECHIP, is described in this proof-of-concept note. Combining both colorimetric and fluorimetric assays, DETECHIP is suitable for lab and field use. More than a conventional spot test which provides a single "yes or no" answer, DETECHIP provides twenty responses for a more complete characterization of suspect material. This is accomplished by visually noting colorimetric and fluorescent changes of carefully selected dyes upon the addition of test analytes, including drugs of abuse, with respect to controls. Color and fluorescence changes are recorded numerically so that a 20 digit …


Toward A Stoichiometric Framework For Evolutionary Biology, Andrew Kerkhoff Jan 2016

Toward A Stoichiometric Framework For Evolutionary Biology, Andrew Kerkhoff

Andrew J Kerkhoff

Ecological stoichiometry, the study of the balance of energy and materials in living systems, may serve as a useful synthetic framework for evolutionary biology. Here, we review recent work that illustrates the power of a stoichiometric approach to evolution across multiple scales, and then point to important open questions that may chart the way forward in this new field. At the molecular level, stoichiometry links hereditary changes in the molecular composition of organisms to key phenotypic functions. At the level of evolutionary ecology, a simultaneous focus on the energetic and material underpinnings of evolutionary tradeoffs and transactions highlights the relationship …


Plant Allometry, Stoichiometry And The Temperature-Dependence Of Primary Productivity, Andrew Kerkhoff Jan 2016

Plant Allometry, Stoichiometry And The Temperature-Dependence Of Primary Productivity, Andrew Kerkhoff

Andrew J Kerkhoff

Aim  While physical constraints influence terrestrial primary productivity, the extent to which geographical variation in productivity is influenced by physiological adaptations and changes in vegetation structure is unclear. Further, quantifying the effect of variability in species traits on ecosystems remains a critical research challenge. Here, we take a macroecological approach and ask if variation in the stoichiometric traits (C: N: P ratios) of plants and primary productivity across global-scale temperature gradients is consistent with a scaling model that integrates recent insights from the theories of metabolic scaling and ecological stoichiometry. Location  This study is global in scope, encompassing a wide …


Arsenic Solid-Phase Speciation In An Alluvial Aquifer System Adjacent To The Himalayan Forehills, Nepal, Scott Johnston, Jasmine Diwakar, Edward Burton Jan 2016

Arsenic Solid-Phase Speciation In An Alluvial Aquifer System Adjacent To The Himalayan Forehills, Nepal, Scott Johnston, Jasmine Diwakar, Edward Burton

Associate Professor Edward D Burton

Alluvial aquifers contaminated by geogenic arsenic often lack direct solid-phase speciation data, hindering efforts to understand landscape-scale spatial heterogeneity and controls on As mobility. Here, we examine solid-phase As and Fe speciation of alluvial aquifer, river and hyporheic-seep sediments along a topographic gradient at the Himalayan foothills/upper-Ganges floodplain margin. We employ a combination of X-ray absorption spectroscopy, selective extracts, electron microscopy and X-ray fluorescence. Source-river sediments were found to contain a mixture of solid-phase As(V) and As(III) species, while vertically heterogeneous bore-hole sediments also contained a solid-phase As-sulfide species. In general, the abundance of reduced As species [As(III) + As-sulfide] …


Alkalinity Conversion Of Bauxite Refinery Residues By Neutralization, M Johnston, M Clark, P Mcmahon, N Ward Jan 2016

Alkalinity Conversion Of Bauxite Refinery Residues By Neutralization, M Johnston, M Clark, P Mcmahon, N Ward

Dr Nicholas J Ward

Red mud remains the largest environmental issue for the alumina industry due to its high pH (>13), fine-grained nature (>90% is <10 >μm), elevated sodium concentration (>50 g/kg), and soluble alkalinity (≈30 g/kg as equivalent CaCO3), which reduce the transport and reuse options of red mud. The neutralization of red mud provides potential reuse options because neutralization lowers pH, increases grain-size (e.g., coagulation), and precipitates or converts alkalinity. This paper investigates the geochemistry of 3 treatments of a red mud to affect neutralization and potentially convert materials from a waste material to a resource. This study investigates two …


Holographic Renormalization Of Asymptotically Lifshitz Spacetimes, Robert Mcnees, Robert Mann Jan 2016

Holographic Renormalization Of Asymptotically Lifshitz Spacetimes, Robert Mcnees, Robert Mann

Robert A McNees IV

A variational formulation is given for a theory of gravity coupled to a massive vector in four dimensions, with Asymptotically Lifshitz boundary conditions on the fields. For theories with critical exponent z=2 we obtain a well-defined variational principle by explicitly constructing two actions with local boundary counterterms. As part of our analysis we obtain solutions of these theories on a neighborhood of spatial infinity, study the asymptotic symmetries, and consider different definitions of the boundary stress tensor and associated charges. A constraint on the boundary data for the fields figures prominently in one of our formulations, and in that case …


Black Holes In The Conical Ensemble, Robert Mcnees, Daniel Grumiller Jan 2016

Black Holes In The Conical Ensemble, Robert Mcnees, Daniel Grumiller

Robert A McNees IV

We consider black holes in an “unsuitable box”: a finite cavity coupled to a thermal reservoir at a temperature different than the black hole’s Hawking temperature. These black holes are described by metrics that are continuous but not differentiable due to a conical singularity at the horizon. We include them in the Euclidean path integral sum over configurations, and analyze the effect this has on black hole thermodynamics in the canonical ensemble. Black holes with a small deficit (or surplus) angle may have a smaller internal energy or larger density of states than the nearby smooth black hole, but they …


Conventions, Definitions, Identities, And Other Useful Formulae, Robert Mcnees Jan 2016

Conventions, Definitions, Identities, And Other Useful Formulae, Robert Mcnees

Robert A McNees IV

As the name suggests, these notes contain a summary of important conventions, definitions, identities, and various formulas that I often refer to. They may prove useful for researchers working in General Relativity, Supergravity, String Theory, Cosmology, and related areas.


Conformal Gravity Holography In Four Dimensions, Daniel Grumiller, Maria Irakleidou, Iva Lovrekovic,, Robert Mcnees Jan 2016

Conformal Gravity Holography In Four Dimensions, Daniel Grumiller, Maria Irakleidou, Iva Lovrekovic,, Robert Mcnees

Robert A McNees IV

We formulate four-dimensional conformal gravity with (anti–)de Sitter boundary conditions that are weaker than Starobinsky boundary conditions, allowing for an asymptotically subleading Rindler term concurrent with a recent model for gravity at large distances. We prove the consistency of the variational principle and derive the holographic response functions. One of them is the conformal gravity version of the Brown–York stress tensor, the other is a “partially massless response”. The on shell action and response functions are finite and do not require holographic renormalization. Finally, we discuss phenomenologically interesting examples, including the most general spherically symmetric solutions and rotating black hole …


The Electric Field At The Chargeless Interface Between Two Regions Of Space, Asim Gangopadhyaya, Robert Mcnees Jan 2016

The Electric Field At The Chargeless Interface Between Two Regions Of Space, Asim Gangopadhyaya, Robert Mcnees

Robert A McNees IV

A common method for solving Poisson's equation in electrostatics is to patch together two or more solutions of Laplace's equation using boundary conditions on the potential and its gradient. Other methods may generate solutions without the need to check these conditions explicitly, and reconciling these solutions with the appropriate boundary conditions can be surprisingly subtle. As a result, a student may arrive at paradoxical conclusions—even in the case of elementary problems—that seem to be at odds with basic physical intuition. We illustrate this issue by showing how the potential of a uniformly charged ring appears to violate continuity of the …


Cosmological Constant As Confining U(1) Charge In Two-Dimensional Dilaton Gravity, Daniel Grumiller, Robert Mcnees, Jakob Salzer Jan 2016

Cosmological Constant As Confining U(1) Charge In Two-Dimensional Dilaton Gravity, Daniel Grumiller, Robert Mcnees, Jakob Salzer

Robert A McNees IV

The cosmological constant is treated as a thermodynamical parameter in the framework of two-dimensional dilaton gravity. We find that the cosmological constant behaves as a U(1) charge with a confining potential, and that such potentials require a novel Born-Infeld boundary term in the action. The free energy and other thermodynamical quantities of interest are derived, from first principles, in a way that is essentially model independent. We discover that there is always a Schottky anomaly in the specific heat and explain its physical origin. Finally, we apply these results to specific examples, like anti-de Sitter–Schwarzschild–Tangherlini black holes, Bañados-Teitelboim-Zanelli black holes …


Boundary Terms Unbound! Holographic Renormalization Of Asymptotically Linear Dilaton Gravity, Robert Mcnees, Robert Mann Jan 2016

Boundary Terms Unbound! Holographic Renormalization Of Asymptotically Linear Dilaton Gravity, Robert Mcnees, Robert Mann

Robert A McNees IV

A variational principle is constructed for gravity coupled to an asymptotically linear dilaton and a p-form field strength. This requires the introduction of appropriate surface terms—also known as 'boundary counterterms'—in the action. The variation of the action with respect to the boundary metric yields a boundary stress tensor, which is used to construct conserved charges that generate the asymptotic symmetries of the theory. In most cases a minimal set of assumptions leads to a unique set of counterterms. However, for certain examples we find families of actions that depend on one or more continuous parameters. We show that the conserved …


Boom Or Bust? Mapping Out The Known Unknowns Of Global Shale Gas Production Potential, Jérôme Hilaire, Nico Bauer, Robert Brecha Jan 2016

Boom Or Bust? Mapping Out The Known Unknowns Of Global Shale Gas Production Potential, Jérôme Hilaire, Nico Bauer, Robert Brecha

Robert J. Brecha

To assess the global production costs of shale gas, we combine global top-down data with detailed bottom-up information. Studies solely based on top-down approaches do not adequately account for the heterogeneity of shale gas deposits and hence, are unlikely to appropriately capture the extraction costs of shale gas. We design and provide an expedient bottom-up method based on publicly available US data to compute the levelized costs of shale gas extraction. Our results indicate the existence of economically attractive areas but also reveal a dramatic cost increase as lower-quality reservoirs are exploited. At the global level, our best estimate suggests …


Shape Invariance And Its Connection To Potential Algebra, Asim Gangopadhyaya, Jeffrey Mallow, Uday Sukhatme Jan 2016

Shape Invariance And Its Connection To Potential Algebra, Asim Gangopadhyaya, Jeffrey Mallow, Uday Sukhatme

Asim Gangopadhyaya

Exactly solvable potentials of nonrelativistic quantum mechanics are known to be shape invariant. For these potentials, eigenvalues and eigenvectors can be derived using well known methods of supersymmetric quantum mechanics. The majority of these potentials have also been shown to possess a potential algebra, and hence are also solvable by group theoretical techniques. In this paper, for a subset of solvable problems, we establish a connection between the two methods and show that they are indeed equivalent.


Holocene Climatic Change And Past Irish Societal Response, David Brown, M. Baillie, J. Palmer, Christian Turney Dec 2015

Holocene Climatic Change And Past Irish Societal Response, David Brown, M. Baillie, J. Palmer, Christian Turney

David C. Brown

No abstract provided.


Bipartite Probe Interval Graphs, Interval Point Bigraphs, And Circular Arcgraphs, David Brown, J. Lundgren Dec 2015

Bipartite Probe Interval Graphs, Interval Point Bigraphs, And Circular Arcgraphs, David Brown, J. Lundgren

David C. Brown

No abstract provided.


Trends Analysis Of Coastal Training Programs In The National Estuarine Research Reserve System: Executive Summary, Claudette Robey, Kevin O'Brien, Kirstin Toth, Dan Baracksay, Michael Mcgoun, Wendy Kellogg, Michael Tevesz Dec 2015

Trends Analysis Of Coastal Training Programs In The National Estuarine Research Reserve System: Executive Summary, Claudette Robey, Kevin O'Brien, Kirstin Toth, Dan Baracksay, Michael Mcgoun, Wendy Kellogg, Michael Tevesz

Michael J. Tevesz

No abstract provided.


How Should Power Quality Be Reported?, Victor Gosbell, D Robinson, Victor Smith, Robert Barr Dec 2015

How Should Power Quality Be Reported?, Victor Gosbell, D Robinson, Victor Smith, Robert Barr

Robert Barr

Regulators are increasingly asking utilities to conduct 'quality control' surveys on selected parts of their power system to establish the level of power quality. This activity leads can lead to a vast amount of data and its reporting needs to be carefully thought out if desired insights are to be achieved. Three styles are identified as serving most purposes - Site, Network and Utility reporting. These are designed to give respectively all the data of one site, summary data for each monitored site in the network, and average values across the utility's system. The data analysis to be used in …


Knowledge Is Free (And Statistics Should Be Too): An Introduction To Using “R” In The Classroom, Brendan Morse Dec 2015

Knowledge Is Free (And Statistics Should Be Too): An Introduction To Using “R” In The Classroom, Brendan Morse

Brendan J. Morse

This workshop will give attendees a hands-on introduction to using R, a freely available statistics software package. The focus of the discussion will be on using R in the classroom for basic mathematical and statistical operations that would be covered in an introductory or intermediate statistics course. The benefit of using R in the classroom is that students can download and install the program (and any add-on package) on their personal computers (Mac or PC) for free and work on statistics projects outside of class. Additionally, we will explore an add-on package that creates a point-and-click interface similar to SPSS …


Forbidden Subgraph Characterization Of Bipartite Unit Probe Interval Graphs, David Brown, L. Langley Dec 2015

Forbidden Subgraph Characterization Of Bipartite Unit Probe Interval Graphs, David Brown, L. Langley

David C. Brown

No abstract provided.


Patient-Centered Appointment Scheduling Using Agent-Based Simulation, Tammy Toscos, Ayten Turkcan, Brad Doebbeling Dec 2015

Patient-Centered Appointment Scheduling Using Agent-Based Simulation, Tammy Toscos, Ayten Turkcan, Brad Doebbeling

Tammy R Toscos

Enhanced access and continuity are key components of patient-centered care. Existing studies show that several interventions such as providing same day appointments, walk-in services, after-hours care, and group appointments, have been used to redesign the healthcare systems for improved access to primary care. However, an intervention focusing on a single component of care delivery (i.e. improving access to acute care) might have a negative impact other components of the system (i.e. reduced continuity of care for chronic patients). Therefore, primary care clinics should consider implementing multiple interventions tailored for their patient population needs. We collected rapid ethnography and observations to …


Chromatographic, Spectroscopic, And Thermal Characterization Of Biofield Energy Treated N,N-Dimethylformamide, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Gunin Saikia, Snehasis Jana Nov 2015

Chromatographic, Spectroscopic, And Thermal Characterization Of Biofield Energy Treated N,N-Dimethylformamide, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Gunin Saikia, Snehasis Jana

Mahendra Kumar Trivedi

N,N-Dimethylformamide (DMF) is a ‘universal’ solvent and has wide variety of applications in organic synthesis, purification, crystallization, and as cross-linking agent. The aim of this study was to evaluate the physicochemical and spectroscopic properties of DMF after the biofield energy treatment using various analytical techniques. DMF sample was divided into two parts, one part (control) remained as untreated, while the other (treated) part was treated with Mr. Trivedi’s biofield energy treatment. The treated sample was subdivided into three parts named as T1, T2, and T3 for gas chromatography-mass spectrometry (GC-MS) analysis. Five relatively intense peaks were observed in the mass …


Thermal, Spectroscopic And Chromatographic Characterization Of Biofield Energy Treated Benzophenone, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Gunin Saikia, Snehasis Jana Nov 2015

Thermal, Spectroscopic And Chromatographic Characterization Of Biofield Energy Treated Benzophenone, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Gunin Saikia, Snehasis Jana

Mahendra Kumar Trivedi

The aim of the present study was to evaluate the impact of biofield energy treatment on the thermal, spectroscopic, and chemical properties of benzophenone. The study was done using various analytical methods such as gas chromatography-mass spectrometry (GC-MS), high performance liquid chromatography (HPLC), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, and ultraviolet-visible (UV-Vis) spectroscopy. The benzophenone sample was divided into two parts, one part was subjected to Mr. Trivedi’s biofield energy treatment, called as treated and the other part was remained as untreated, called as control. Mass spectra showed the molecular ion peak at m/z = 182 in …


Experimental Investigation On Physical, Thermal And Spectroscopic Properties Of 2-Chlorobenzonitrile: Impact Of Biofield Treatment, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Ragini Singh, Snehasis Jana Nov 2015

Experimental Investigation On Physical, Thermal And Spectroscopic Properties Of 2-Chlorobenzonitrile: Impact Of Biofield Treatment, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Ragini Singh, Snehasis Jana

Mahendra Kumar Trivedi

2-chlorobenzonitrile (2-ClBN) is widely used in the manufacturing of azo dyes, pharmaceuticals, and as intermediate in various chemical reactions. The aim of present study was to evaluate the impact of biofield treatment on physical, thermal and spectroscopic properties of 2-ClBN. 2-ClBN sample was divided into two groups that served as treated and control. The treated group received Mr. Trivedi’s biofield treatment. Subsequently, the control and treated samples were evaluated using X-ray diffraction (XRD), surface area analyser, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) and ultraviolet-visible (UV-Vis) spectroscopy. XRD result showed a decrease in crystallite size in …


Physicochemical And Spectroscopic Characteristics Of Biofield Treated P-Chlorobenzophenone, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Khemraj Bairwa, Snehasis Jana Nov 2015

Physicochemical And Spectroscopic Characteristics Of Biofield Treated P-Chlorobenzophenone, Mahendra Kumar Trivedi, Alice Branton, Dahryn Trivedi, Gopal Nayak, Khemraj Bairwa, Snehasis Jana

Mahendra Kumar Trivedi

p-Chlorobenzophenone (p-CBP) is the important chemical intermediate used for the synthesis of several pharmaceutical drugs like fenofibrate, cetirizine, alprazolam, and benzodiazepine. The aim of this study was set to evaluate the impact of biofield energy treatment on physicochemical and spectroscopic properties of p-CBP. The study was accomplished in two groups i.e. control and treated. The treated group was subjected to Mr. Trivedi’s biofield energy treatment. Subsequently, the control and treated samples of p-CBP were analyzed using X-ray diffraction (XRD), particle size analyzer, surface area analyzer, differential scanning calorimetry (DSC), thermogravimetric analysis-derivative thermogravimetric analysis (TGA-DTG), Fourier transform infrared (FT-IR), and ultraviolet-visible …


The Physical Tourist, A Science Guide For The Traveler, Tom Greenslade Nov 2015

The Physical Tourist, A Science Guide For The Traveler, Tom Greenslade

Thomas B. Greenslade, Jr.

Typical travel guides have sections on architecture, art, literature, music and cinema. Rarely are any science-related sites identified. For example, a current travel guide for Germany contains one tidbit on science: Einstein is identified as the most famous citizen of Ulm. By contrast, this travel guide walks a tourist through Berlin and identifies where Max Planck started the quantum revolution, where Einstein lived and gave his early talks on general relativity, and where, across the street, Einstein’s books were burned by the Nazis. Or, if you are walking in Paris, this guide tells you where radioactivity was discovered and where …