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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 ...


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

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. 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 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 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 ...


Pharmacology Of Organic Cation Transporters: Focus On Structure-Function Relationships In Oct3 (Slc22a3), Dan C. Li May 2015

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 May 2015

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 May 2015

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 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 ...


If You Don’T Want To Talk About Food, Don’T Sit Next To Me, Judith L. Polk May 2015

If You Don’T Want To Talk About Food, Don’T Sit Next To Me, Judith L. Polk

Master of Arts in Professional Writing Capstones

If You Don’t Want to Talk About Food, Don’t Sit Next to Me has as its main characters the same qualities taken from the new philosophy of Le Cordon Bleu: “Aspire, Discover, Flourish, Delight, and Thrive, and the memories made while a full-time student.


Novelty Or Knowledge? A Study Of Using A Student Response, Tasha M. Thames May 2015

Novelty Or Knowledge? A Study Of Using A Student Response, Tasha M. Thames

Dissertations

The advancement in technology integration is laying the groundwork of a paradigm shift in the higher education system (Noonoo, 2011). The National Dropout Prevention Center (n.d.) [JS1] claims that technology offers some of the best opportunities for presenting instruction to engage students in meaningful education, addressing multiple intelligences, and adjusting to students’ various learning styles. The purpose of this study was to investigate if implementing clicker technology would have a statistically significant difference on student retention and student achievement, while controlling for learning styles, for students in non-major biology courses who were and were not subjected to the technology ...


Observations On The Life History Of The Bayou Killifish, Fundulus Pulvereus (Everman 1899) In Mississippi Tidal Marshes, Leah C. Gaines May 2015

Observations On The Life History Of The Bayou Killifish, Fundulus Pulvereus (Everman 1899) In Mississippi Tidal Marshes, Leah C. Gaines

Master's Theses

This study provides insight into the life history of the relatively unknown intertidal marsh fish Fundulus pulvereus (Everman), the bayou killifish. Monthly sampling for F. pulvereus took place in three different Mississippi tidal marshes over a period of 17 months (n=445). Observations on the diet, parasite fauna, and fecundity of the bayou killifish were documented on all specimens collected. Percent Occurrence and Percent Number coupled along with multivariate analyses indicated seasonal, site, and ontogenetic shifts in the diet of F. pulvereus. Dominant prey items consumed by F. pulvereus were copepods, mites, chironomids, and terrestrial and aquatic insects. The bayou ...


Deciphering The Functional Collaboration Of Mid And Bric-A-Brac 2 As Potential Regulators Of Cellular Proliferation Within Adult Drosophila Ovaries, Petra Visic May 2015

Deciphering The Functional Collaboration Of Mid And Bric-A-Brac 2 As Potential Regulators Of Cellular Proliferation Within Adult Drosophila Ovaries, Petra Visic

Master's Theses

Stem cell niches are highly organized and specialized microenvironments located within specific tissues of both vertebrate and invertebrate organisms [1]. In Drosophila melanogaster, three distinct stem cell niches have been identified within the ovary including the germline stem cell (GSC), follicle stem cell (FSC), and escort stem cell (ESC) niche. Recently, Fregoso-Lomas et al. [2] reported that Gurken/Epidermal Growth Factor Receptor (EGFR) signaling is modulated within posterior ovarian follicle cells by Midline (Mid). The mid gene encodes a T-box transcription factor protein that specifies cell fates in the developing heart [3][4], central nervous system [5][6], epidermis [7 ...