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Full-Text Articles in Life Sciences

Phytochemical Analysis And Biological Activities Of Cola Nitida Bark, Durand Dah-Nouvlessounon, Laboratoire Baebib, Ufr-Svt, University Of Ouagadougou, Mamoudou H. Dicko Prof., Lamine Baba-Moussa Jan 2031

Phytochemical Analysis And Biological Activities Of Cola Nitida Bark, Durand Dah-Nouvlessounon, Laboratoire Baebib, Ufr-Svt, University Of Ouagadougou, Mamoudou H. Dicko Prof., Lamine Baba-Moussa

Pr. Mamoudou H. DICKO, PhD

The aim of this study is to investigate some biological effects of Cola nitida’s bark after phytochemical screening. The bark was collected, dried, and then powdered for the phytochemical screening and extractions. Ethanol and ethyl acetate extracts of C. nitida were used in this study. The antibacterial activity was tested on ten reference strains and 28 meat isolated Staphylococcus strains by disc diffusionmethod. The antifungal activity of three fungal strains was determined on the Potato-Dextrose Agar medium mixed with the appropriate extract. The antioxidant activity was determined by DPPH and ABTS methods. Our data revealed the presence of various ...


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

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 ...


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

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 Jun 2015

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 Jun 2015

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 May 2015

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 May 2015

‘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 May 2015

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

MODVIS Workshop

In the natural word, 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 illuminant. Hyperspectral radiance images were acquired at roughly hourly intervals in four outdoor scenes. From these time-lapse hyperspectral sequences, spatial cone-excitation ratios were estimated at 10,000 randomly sampled pairs ...


Investigating The Role Of Wolbachia Endosymbionts In The Expansion Of The F Element In Drosophila Ananassae, Elizabeth J. Chen May 2015

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 ...


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

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 May 2015

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 May 2015

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 May 2015

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 May 2015

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 May 2015

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 May 2015

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 May 2015

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.


A Recurrent Multilayer Model With Hebbian Learning And Intrinsic Plasticity Leads To Invariant Object Recognition And Biologically Plausible Receptive Fields, Michael Teichmann, Fred H. Hamker May 2015

A Recurrent Multilayer Model With Hebbian Learning And Intrinsic Plasticity Leads To Invariant Object Recognition And Biologically Plausible Receptive Fields, Michael Teichmann, Fred H. Hamker

MODVIS Workshop

Much effort has been spent to develop biologically plausible models for different aspects of the processing in the visual cortex. However, most of these models are not investigated with respect to the functionality of the neural code for the purpose of object recognition comparable to the framework of deep learning in the machine learning community.
We developed a model of V1 and V2 based on anatomical evidence of the layered architecture, using excitatory and inhibitory neurons where the connectivity to each neuron is learned in parallel. We address learning by three different mechanisms of plasticity: intrinsic plasticity, Hebbian learning with ...


A Computational Model To Account For Dynamics Of Spatial Updating Of Remembered Visual Targets Across Slow And Rapid Eye Movements, Yalda Mohsenzadeh, J. Douglas Crawford May 2015

A Computational Model To Account For Dynamics Of Spatial Updating Of Remembered Visual Targets Across Slow And Rapid Eye Movements, Yalda Mohsenzadeh, J. Douglas Crawford

MODVIS Workshop

Despite the ever-changing visual scene on the retina between eye movements, our perception of the visual world is constant and unified. It is generally believed that this space constancy is due to the brain’s ability of spatial updating. Although many efforts have been made to discover the mechanism underlying spatial updating across eye movements, still there are many unanswered questions about the neuronal mechanism of this phenomenon.

We developed a state space model for updating gaze-centered spatial information. To explore spatial updating, we considered two kinds of eye movements, saccade and smooth pursuit. The inputs to our proposed model ...


A Model Of Repetitive Microsaccades, Coupled With Pre-Microsaccadic Changes In Vision, Is Sufficient To Account For Both Attentional Capture And Inhibition Of Return In Posner Cueing, Ziad M. Hafed, Xiaoguang Tian May 2015

A Model Of Repetitive Microsaccades, Coupled With Pre-Microsaccadic Changes In Vision, Is Sufficient To Account For Both Attentional Capture And Inhibition Of Return In Posner Cueing, Ziad M. Hafed, Xiaoguang Tian

MODVIS Workshop

When a cue is presented at a location, orienting efficacy towards that location is improved relative to other locations (“attentional capture”), but only briefly; a mere few hundred milliseconds later, orienting incurs large costs. These costs have been classically termed “inhibition of return” (IOR), alluding to voluntary, cognitive strategies avoiding perseverance at one location. However, despite this popular hypothesis, the origins of both attentional capture and IOR remain elusive. Here we show that both of these phenomena can be accounted for by a single concept of oculomotor rhythmicity, and one that involves the entire gamut of saccadic activity including microsaccades ...


Object Recognition And Visual Search With A Physiologically Grounded Model Of Visual Attention, Frederik Beuth, Fred H. Hamker May 2015

Object Recognition And Visual Search With A Physiologically Grounded Model Of Visual Attention, Frederik Beuth, Fred H. Hamker

MODVIS Workshop

Visual attention models can explain a rich set of physiological data (Reynolds & Heeger, 2009, Neuron), but can rarely link these findings to real-world tasks. Here, we would like to narrow this gap with a novel, physiologically grounded model of visual attention by demonstrating its objects recognition abilities in noisy scenes.

To base the model on physiological data, we used a recently developed microcircuit model of visual attention (Beuth & Hamker, in revision, Vision Res) which explains a large set of attention experiments, e.g. biased competition, modulation of contrast response functions, tuning curves, and surround suppression. Objects are represented by object-view specific neurons, learned via a trace learning approach (Antonelli et al., 2014, IEEE TAMD). A visual cortex model combines the microcircuit with neuroanatomical properties like top-down attentional processing, hierarchical-increasing receptive field sizes, and synaptic transmission delays. The visual cortex model is complemented by a model of the frontal eye field (Zirnsak et al., 2011, Eur J Neurosci).

We evaluated the model on a realistic object recognition task in which a given target has to be localized in a scene (guided visual search task), using 100 different target objects, 1000 scenes, and two backgrounds. The model achieves an accuracy of 92% at black, and of 71% at white-noise backgrounds. We found that two of the underlying, neuronal attention mechanisms are prominently relevant for guided visual search: amplification of neurons preferring the target; and suppression of neurons encoding distractors or background noise.


Modeling Visual Features To Recognize Biological Motion: A Developmental Approach, Giulio Sandini, Nicoletta Noceti, Alessandra Sciutti, Francesco Rea, Alessandro Verri, Francesca Odone May 2015

Modeling Visual Features To Recognize Biological Motion: A Developmental Approach, Giulio Sandini, Nicoletta Noceti, Alessandra Sciutti, Francesco Rea, Alessandro Verri, Francesca Odone

MODVIS Workshop

In this work we deal with the problem of designing and developing computational vision models – comparable to the early stages of the human development – using coarse low-level information.

More specifically, we consider a binary classification setting to characterize biological movements with respect to non-biological dynamic events. To this purpose, our model builds on top of the optical flow estimation, and abstract the representation to simulate the limited amount of visual information available at birth. We take inspiration from known biological motion regularities explained by the Two-Thirds Power Law, and design a motion representation that includes different low-level features, which can ...


Identifying Temporal Differences In Vibration Receptor Activation In The Sand Fiddler Crab, Uca Pugilator, Andre' Matthew Agassi May 2015

Identifying Temporal Differences In Vibration Receptor Activation In The Sand Fiddler Crab, Uca Pugilator, Andre' Matthew Agassi

University of Tennessee Honors Thesis Projects

No abstract provided.


Inhibition Of Breast Cancer Cell Proliferation By Diarylthiourea Analog, Sl1-18, Maryam Fallatah Apr 2015

Inhibition Of Breast Cancer Cell Proliferation By Diarylthiourea Analog, Sl1-18, Maryam Fallatah

Scholarly and Creative Works Conference

Breast cancer is the most common malignancy that occurs in women in the US and has the second highest cancer-associated mortality rate. Depending on the expression of estrogen receptor α (ERα), breast cancer can be classified as ER positive or negative. Current drugs used to treat ER+ cancers include selective estrogen receptor modulators (SERMs) and selective estrogen receptor down-regulators (SERDs). Unfortunately, prolonged exposure to these drugs often leads to the development of acquired resistance. Consequently, there is a great need to develop alternative therapeutic options. Flexible heteroarotinoids (Flex-Hets) are groups of compounds that are derived from retinoids. Flex-Hets have been ...


Coral Growth Under Thermal Stress And Different Levels Of Light Intensity In Acropora Aspera., Devan Y. Klein, Mary W. Barana, Leeanne A. Obilor Apr 2015

Coral Growth Under Thermal Stress And Different Levels Of Light Intensity In Acropora Aspera., Devan Y. Klein, Mary W. Barana, Leeanne A. Obilor

Scholarly and Creative Works Conference

In this study we examined the growth rates of coral species Acropora aspera in conditions of high thermal stress which are expected to become more common because of climate change. During higher than normal temperature periods, corals can experience bleaching which is the loss of algal symbionts from their tissue. Since corals depend on these photosynthetic organisms for most of their nutrition, this loss can lead to mass mortality. However, if the period of thermal stress happens during cloudy weather, bleaching events are less severe, and thus it is possible that shading reefs could help mitigate the effects of warmer ...


Analysis Of The Diets Of The Northern Spotted Owl And Barred Owl, Valeria Briones Apr 2015

Analysis Of The Diets Of The Northern Spotted Owl And Barred Owl, Valeria Briones

Scholarly and Creative Works Conference

The Northern Spotted Owl, a once thriving species is now a threatened species and on the verge of endangerment. The Barred Owl, a species native to the eastern United States over the past few centuries has expanded its range into that of the Northern Spotted Owl, causing a major threat to the Northern Spotted Owl Populations. This paper is a synthesis of the existing literature of the diets of the Northern Spotted Owl and Barred Owl individually as well as in areas in which they occur sympatrically. With this summary of literature, the reader can gain an understanding of the ...


Investigation Of Structure-Activity Relationships Of Antimalarial Drugs Through Novel Plasmodium Falciparum Chloroquine Resistance Resistance Transporter (Pfcrt), Bianca Sanchez Mora, Samuel Lemus, Danielle Nicole Flordeliza, Jillian Nunes, Alexis Valdovinos Apr 2015

Investigation Of Structure-Activity Relationships Of Antimalarial Drugs Through Novel Plasmodium Falciparum Chloroquine Resistance Resistance Transporter (Pfcrt), Bianca Sanchez Mora, Samuel Lemus, Danielle Nicole Flordeliza, Jillian Nunes, Alexis Valdovinos

Scholarly and Creative Works Conference

Mutation in the P. falciparum resistance chloroquine transporter (PfCRT) protein causes chloroquine resistance and alters susceptibility to various antimalarial drugs. Mutant PfCRT transports chloroquine out of the parasite digestive vacuole; however, the molecular details of drug-receptor interaction are poorly understood. The antiviral drug amantadine has moderate potency against P. falciparum and acts to reduce the level of chloroquine resistance determined by the pfcrt haplotype. In accordance, chloroquine-resistant parasites show enhanced sensitivity to amantadine. We used continuous, step-wise amantadine selection on three chloroquine-resistant lines of the P. falciparum 106/1 strain. Each of these lines contains a unique pfcrt allele differing ...


Dissipation Rate Of Turbulent Kinetic Energy In Diel Vertical Migrations: Comparison Of Ansys Fluent Model To Measurements, Cayla Whitney Dean, Alexandre Soloviev, Amy Hirons, Tamara M. Frank, Ocean Data Technologies, Inc. Apr 2015

Dissipation Rate Of Turbulent Kinetic Energy In Diel Vertical Migrations: Comparison Of Ansys Fluent Model To Measurements, Cayla Whitney Dean, Alexandre Soloviev, Amy Hirons, Tamara M. Frank, Ocean Data Technologies, Inc.

Oceanography Faculty Proceedings, Presentations, Speeches, Lectures

No abstract provided.


Comparison Of Downstream Cell Survival Responses In Huvecs And Hlecs During Vegf Signaling, Haley Smith Apr 2015

Comparison Of Downstream Cell Survival Responses In Huvecs And Hlecs During Vegf Signaling, Haley Smith

Undergraduate Research And Scholarly Achievement Symposium

Comparison of Downstream Cell Survival Responses in HUVECs and HLECs During VEGF Signaling

Author: Haley M. Smith

Mentor: Thomas L. Vandergon

Angiogenesis and lymphangiogenesis are vital processes that allow the formation of new blood and lymph vessels from existing blood or lymph vessels. Formation of these vessels is essential to bring oxygen and nutrients to the body as well as maintaining tissue fluid balance. New blood or lymph vessel growth occurs in response to Vascular Endothelial Growth Factor (VEGF) signaling to vascular endothelial cells. The VEGF signal molecules bind to cell surface receptors and elicit a variety of responses including ...


Quantifying Land Cover Change Due To Petroleum Exploration And Production In The Haynesville Shale Region Using Remote Sensing, Daniel Unger, I-Kuai Hung, Kenneth W. Farrish, Darinda Dans Apr 2015

Quantifying Land Cover Change Due To Petroleum Exploration And Production In The Haynesville Shale Region Using Remote Sensing, Daniel Unger, I-Kuai Hung, Kenneth W. Farrish, Darinda Dans

Faculty Publications

The Haynesville Shale lies under areas of Louisiana and Texas and is one of the largest gas plays in the U.S. Encompassing approximately 2.9 million ha, this area has been subject to intensive exploration for oil and gas, while over 90% of it has traditionally been used for forestry and agriculture. In order to detect the landscape change in the past few decades, Landsat Thematic Mapper (TM) imagery for six years (1984, 1989, 1994, 2000, 2006, and 2011) was acquired. Unsupervised classifications were performed to classify each image into four cover types: agriculture, forest, well pad, and other ...