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The Use Of Argumentation In Socio-Scientific Issues: Enhancing Evolutionary Biology Instruction, Heath R. Marchand 2015 The College at Brockport

The Use Of Argumentation In Socio-Scientific Issues: Enhancing Evolutionary Biology Instruction, Heath R. Marchand

Education and Human Development Master's Theses

With the adoption of the Next Generation Science Standards (NGSS), further emphasis in science education is being placed on preparing students to become more informed voters regarding social, ethical, economic and political topics that affect contemporary society. Parallel to this shift is a stronger emphasis on integrating evolutionary theory as a unifying concept in the biological sciences. Given that evolution is one of the aforementioned topics commonly discussed and debated about in social and political arenas, ensuring that instruction provides students from all backgrounds a comprehensive understanding of its principals is becoming increasingly important in contemporary science education. Chapter II ...


Monitoring Of Pseudomonas Aeruginosa Toxins Via Miniaturized Electrochemical Assemblies, Thaddaeus Webster 2015 Northeastern University

Monitoring Of Pseudomonas Aeruginosa Toxins Via Miniaturized Electrochemical Assemblies, Thaddaeus Webster

Chemical Engineering Dissertations

The production of pyocyanin from the opportunistic pathogen Pseudomonas aeruginosa was probed using a variety of miniaturized electrochemical systems. Goal 1 used disposable screen printed carbon electrodes to measure pyocyanin in medically relevant samples showing for the first time that pyocyanin can be detected at medically relevant concentrations (1-100 µM) without sample processing. Goal 2 coupled these same electrodes with Polydimethylsiloxane growth chambers to expose P. aeruginosa biofilms to varying concentrations of colistin sulphate. A reduction in electrochemical signal from pyocyanin, of approximately 80% when exposed to 100 mg/L colistin sulphate, highlights this molecules relation to biofilm health. Goal ...


Assessing The Urban Forest Values An Institutional Sector Approach, Anthony M. Rodriguez Ph.D. 2015 Texas Southern University

Assessing The Urban Forest Values An Institutional Sector Approach, Anthony M. Rodriguez Ph.D.

Anthony M Rodriguez Ph.D.

The poster present the foundation of a study in progress that demonstrates and maps the urban forest values. Using ARCGIS the paper will model social change and the potential for expanding or not the natural environment focusing on the values and the projected change based on the sectors position in reference to the sustainability and more specifically the urban forest. With ArcGIS the paper will demonstrate values and social change potential by analyzing and relating community survey responses to the spatial change.


Agenda: Innovations In Managing Western Water: New Approaches For Balancing Environmental, Social, And Economic Outcomes, University of Colorado Boulder. Getches Wilkinson Center for Natural Resources, Energy, and the Environment 2015 University of Colorado Law School

Agenda: Innovations In Managing Western Water: New Approaches For Balancing Environmental, Social, And Economic Outcomes, University Of Colorado Boulder. Getches Wilkinson Center For Natural Resources, Energy, And The Environment

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Many aspects of western water allocation and management are the product of independent and uncoordinated actions, several occurring a century or more ago. However, in this modern era of water scarcity, it is increasingly acknowledged that more coordinated and deliberate decision-making is necessary for effectively balancing environmental, social, and economic objectives. In recent years, a variety of forums, processes, and tools have emerged to better manage the connections between regions, sectors, and publics linked by shared water systems. In this event, we explore the cutting edge efforts, the latest points of contention, and the opportunities for further progress.


A Prototype On-Line Aotf Hyperspectral Image Acquisition System For Tenderness Assessment Of Beef Carcasses, Govindarajan Konda Naganathan, Kim Cluff, Ashok Samal, Chris Calkins, David D. Jones, Carol Lorenzen, Jeyamkondan Subbiah 2015 University of Nebraska - Lincoln

A Prototype On-Line Aotf Hyperspectral Image Acquisition System For Tenderness Assessment Of Beef Carcasses, Govindarajan Konda Naganathan, Kim Cluff, Ashok Samal, Chris Calkins, David D. Jones, Carol Lorenzen, Jeyamkondan Subbiah

Faculty Publications in Food Science and Technology

A prototype on-line acousto-optic tunable filter (AOTF)-based hyperspectral image acquisition system (λ = 450– 900 nm) was developed for tenderness assessment of beef carcasses. Hyperspectral images of ribeye muscle on stationary hanging beef carcasses (n = 338) at 2-day postmortem were acquired in commercial beef slaughter or packing plants. After image acquisition, a strip steak was cut from each carcass, vacuum packaged, aged for 14 days, cooked, and slice shear force tenderness scores were collected by an independent lab. Beef hyperspectral images were mosaicked together and principal component (PC) analysis was conducted to reduce the spectral dimension. Six different textural feature ...


Characterizing Receptive Field Selectivity In Area V2, Corey M. Ziemba, Robbe LT Goris, J Anthony Movshon, Eero P. Simoncelli 2015 New York University

Characterizing Receptive Field Selectivity In Area V2, Corey M. Ziemba, Robbe Lt Goris, J Anthony Movshon, Eero P. Simoncelli

MODVIS Workshop

The computations performed by neurons in area V1 are reasonably well understood, but computation in subsequent areas such as V2 have been more difficult to characterize. When stimulated with visual stimuli traditionally used to investigate V1, such as sinusoidal gratings, V2 neurons exhibit similar selectivity (but with larger receptive fields, and weaker responses) relative to V1 neurons. However, we find that V2 responses to synthetic stimuli designed to produce naturalistic patterns of joint activity in a model V1 population are more vigorous than responses to control stimuli that lacked this naturalistic structure (Freeman, et. al. 2013). Armed with this signature ...


‘Edge’ Integration Explains Contrast And Assimilation In A Gradient Lightness Illusion, Michael E. Rudd 2015 mrudd@u.washington.edu

‘Edge’ Integration Explains Contrast And Assimilation In A Gradient Lightness Illusion, Michael E. Rudd

MODVIS Workshop

In the ‘phantom’ illusion (Galmonte, Soranzo, Rudd, & Agostini, submitted), either an incremental or a decremental target, when surrounded by a luminance gradient, can to be made to appear as an increment or a decrement, depending on the gradient width. For wide gradients, incremental targets appear as increments and decremental targets appear as decrements. For narrow gradients, the reverse is true. Here, I model these phenomena with a two-stage neural lightness theory (Rudd, 2013, 2014) in which local steps in log luminance are first encoded by oriented spatial filters operating on a log-transformed version of the image; then the filter outputs are appropriately integrated along image paths directed towards the target. A contrast gain control mechanism adjusts each filter’s gain on the basis of the outputs of other nearby filters. The weighted contribution of each filter to the target lightness decays exponentially with distance, as do the strengths of the between-filter gain modulations. I simulate the lightnesses of incremental and decremental targets as a function of gradient width and show that the model reproduces the key properties of the phantom illusion, even when the gain applied to decremental luminance ...


Time-Lapse Statistics Of Cone Signals From Natural Scenes, David H. Foster, Kinjiro Amano, Sérgio M C Nascimento 2015 University of Manchester

Time-Lapse Statistics Of Cone Signals From Natural Scenes, David H. Foster, Kinjiro Amano, Sérgio M C Nascimento

MODVIS Workshop

In the natural world, the spectrum and geometry of the illumination from the sun and sky vary over the day. These geometric changes make it especially difficult to extract from the reflected light invariant signals for surface color perception. The aim of this study was to test the utility of certain combinations of retinal cone excitations, in particular, spatial cone-excitation ratios, known to be approximately invariant under non-geometric changes in illumination. Hyperspectral radiance images were acquired at roughly hourly intervals in four outdoor scenes in the Minho region of Portugal. Spatial resolution of the camera was 1344×1024 pixels. Peak-transmission ...


Investigating The Role Of Wolbachia Endosymbionts In The Expansion Of The F Element In Drosophila Ananassae, Elizabeth J. Chen 2015 Washington University in St Louis

Investigating The Role Of Wolbachia Endosymbionts In The Expansion Of The F Element In Drosophila Ananassae, Elizabeth J. Chen

Undergraduate Theses—Unrestricted

At 4.2 Mb overall, the Drosophila melanogaster Muller F element (dot chromosome) is an unusual autosome; it is broadly heterochromatic, but the distal 1.3 Mb has a gene density and expression pattern similar to other autosomes. More intriguing is the large expansion of the D. ananassae F element (~20 Mb). Elucidating the factors that contribute to this expansion could improve our understanding of how heterochromatic domains are maintained and amplified.

Previous analyses show that the lateral gene transfer (LGT) of Wolbachia (the most widespread intracellular bacteria in the Rickettsiales order) into the D. ananassae genome is an important ...


Pharmacology Of Organic Cation Transporters: Focus On Structure-Function Relationships In Oct3 (Slc22a3), Dan C. Li 2015 Washington University in St Louis

Pharmacology Of Organic Cation Transporters: Focus On Structure-Function Relationships In Oct3 (Slc22a3), Dan C. Li

Undergraduate Theses—Unrestricted

Organic Cation Transporters (OCTs) are polyspecific, facilitative transporters that play major roles in metabolite and drug clearance. OCTs are promising drug targets and elucidating their mechanisms of substrate recognition is crucial for rational drug design. OCT-mediated transport of polyvalent cations remains unexplored. OCT-expressing Xenopus laevis oocytes were used to assess transport of polyamines, ubiquitous polyvalent cations of broad physiological import, but for which transport mechanisms are unknown. Dose-response analysis of radiolabelled substrate uptake revealed that polyamines are relatively low affinity, but high turnover substrates for OCTs compared to model substrate methyl-4-phenylpyridinium (MPP+). Polyamine analogs of varying hydrophobic character were screened ...


The Role Of Gpr126 In Myelin Maintenance And Regeneration In The Peripheral Nervous System, Jessica A. Joseph 2015 Washington University in St. Louis

The Role Of Gpr126 In Myelin Maintenance And Regeneration In The Peripheral Nervous System, Jessica A. Joseph

Undergraduate Theses—Unrestricted

Myelin is a multilayered insulating membrane that allows rapid propagation of electrical signals and provides neurotrophic and cellular support to axons. Specialized glial cells called oligodendrocytes synthesize myelin in the central nervous system (CNS), while Schwann cells myelinate axons in the peripheral nervous system (PNS). Irregular myelin formation or myelin degeneration leads to debilitating diseases like multiple sclerosis (MS) in the CNS and Charcot-Marie-Tooth Disease in the PNS. However, the molecular mechanisms behind myelin maintenance or regeneration after injury or disease are not well understood. Adhesion G Protein- Coupled Receptors (aGPCRs) are a unique class of GPCRs, in that they ...


The C-Terminal Linker Of Ftsz Acts As An Intrinsically Disordered Peptide During Cell Division In Bacillus Subtilis, Steven Grigsby 2015 Washington University in St Louis

The C-Terminal Linker Of Ftsz Acts As An Intrinsically Disordered Peptide During Cell Division In Bacillus Subtilis, Steven Grigsby

Undergraduate Theses—Unrestricted

The bacterial tubulin homologue FtsZ polymerizes in vitro in a GTP-dependent manner to form long, single stranded filaments. In cells, these filaments assemble at the nascent division site, interacting laterally to form the contractile Z ring. The Z ring serves as a scaffold for the rest of the division machinery and constricts at the leading edge of the invaginating septum during cytokinesis. The FtsZ polypeptide consists of three primary domains: the N-terminal globular core consisting of 315 residues that contains the GTP binding site, a variable and flexible C-terminal linker (CTL) consisting of 50 residues, and a conserved region at ...


The Bounded Log-Odds Model Of Frequency And Probability Distortion, Hang Zhang, Laurence T. Maloney 2015 Peking University

The Bounded Log-Odds Model Of Frequency And Probability Distortion, Hang Zhang, Laurence T. Maloney

MODVIS Workshop

No abstract provided.


Putting Saliency In Its Place, John K. Tsotsos 2015 York University

Putting Saliency In Its Place, John K. Tsotsos

MODVIS Workshop

The role of attention and the place within the visual processing stream where the concept of saliency has been situated is critically examined by considering the experimental evidence and performing tests that link experiment to computation.


Towards A Unified Computational Model Of Contextual Interactions Across Visual Modalities, David A. Mély, Thomas Serre 2015 Brown University

Towards A Unified Computational Model Of Contextual Interactions Across Visual Modalities, David A. Mély, Thomas Serre

MODVIS Workshop

The perception of a stimulus is largely determined by its surrounding. Examples abound from color (Land and McCann, 1971), disparity (Westheimer, 1986) and motion induction (Anstis and Casco, 2006) to orientation tilt effects (O’Toole and Wenderoth, 1976). Some of these phenomena have been studied individually using monkey neurophysiology techniques. In these experiments, a center stimulus is typically used to probe a cell’s classical “center” receptive field (cRF), whose activity is then modulated by an annular “surround” (extra-cRF) stimulus. While this center-surround integration (CSI) has been well characterized, a theoretical framework which unifies these different phenomena across visual modalities ...


A Conceptual Framework Of Computations In Mid-Level Vision, Jonas Kubilius, Johan Wagemans, Hans P. Op de Beeck 2015 University of Leuven

A Conceptual Framework Of Computations In Mid-Level Vision, Jonas Kubilius, Johan Wagemans, Hans P. Op De Beeck

MODVIS Workshop

The goal of visual processing is to extract information necessary for a variety of tasks, such as grasping objects, navigating in scenes, and recognizing them. While ultimately these tasks might be carried out by separate processing pathways, they nonetheless share a common root in the early and intermediate visual areas. What representations should these areas develop in order to facilitate all of these higher-level tasks? Several distinct ideas have received empirical support in the literature so far: (i) boundary feature detection, such as edge, corner, and curved segment extraction; (ii) second-order feature detection, such as the difference in orientation or ...


Binocular 3d Motion Perception As Bayesian Inference, Martin Lages, Suzanne Heron 2015 University of Glasgow

Binocular 3d Motion Perception As Bayesian Inference, Martin Lages, Suzanne Heron

MODVIS Workshop

The human visual system encodes monocular motion and binocular disparity input before it is integrated into a single 3D percept. Here we propose a geometric-statistical model of human 3D motion perception that solves the aperture problem in 3D by assuming that (i) velocity constraints arise from inverse projection of local 2D velocity constraints in a binocular viewing geometry, (ii) noise from monocular motion and binocular disparity processing is independent, and (iii) slower motions are more likely to occur than faster ones. In two experiments we found that instantiation of this Bayesian model can explain perceived 3D line motion direction under ...


A Binocular Model For Motion Integration In Mt Neurons, Pamela M. Baker, Wyeth Bair 2015 University of Washington - Seattle Campus

A Binocular Model For Motion Integration In Mt Neurons, Pamela M. Baker, Wyeth Bair

MODVIS Workshop

Processing of visual motion by neurons in MT has long been an active area of study, however circuit models detailing the computations underlying binocular integration of motion signals remains elusive. Such models are important for studying the visual perception of motion in depth (MID), which involves both frontoparallel (FP) visual motion and binocular signal integration. Recent studies (Czuba et al. 2014, Sanada and DeAngelis 2014) have shown that many MT neurons are MID sensitive, contrary to the prevailing view (Maunsell and van Essen, 1983). These novel data are ideal for constraining models of binocular motion integration in MT. We have ...


A Critical Evaluation Of Computational Mechanisms Of Binocular Disparity Processing, Junkyung Kim, David A. Mély, Thomas Serre 2015 Brown University

A Critical Evaluation Of Computational Mechanisms Of Binocular Disparity Processing, Junkyung Kim, David A. Mély, Thomas Serre

MODVIS Workshop

The past decades of research in visual neuroscience have generated a large and disparate body of literature on the computation of binocular disparity in the primary visual cortex. Models have been proposed to describe specific phenomena, yet we lack a theoretical framework which is grounded in neurophysiology and also explains the effectiveness of disparity computation. Here, we examine neural circuits that are thought to play an important role in the computation of binocular disparity. Starting with the binocular energy model (Ohzawa et al. 1990), we consider plausible extensions which include suppressive mechanisms from units tuned to different phase disparities (Tanabe ...


Modeling Shape Representation In Area V4, Wyeth Bair, Dina Popovkina, Abhishek De, Anitha Pasupathy 2015 University of Washington

Modeling Shape Representation In Area V4, Wyeth Bair, Dina Popovkina, Abhishek De, Anitha Pasupathy

MODVIS Workshop

Our model builds on a convolutional-style neural network with hierarchical stages representing processing steps in the ventral visual pathway. It was designed to capture the translation-invariance and shape-selectivity of neurons in area V4. The model uses biologically plausible linear filters at the front end, normalization and sigmoidal nonlinear activation functions. The max() function is used to generate translation invariance.


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