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Inference And Control In Regulatory Genomics, Siddharth Sharma 2018 University of Maryland College Park

Inference And Control In Regulatory Genomics, Siddharth Sharma

Biology and Medicine Through Mathematics Conference

No abstract provided.


Computational Study Of Ligand-Dependent Oligomerization Of Ribonucleotide Reductase, Bill Pham 2018 University of Tennessee, Knoxville

Computational Study Of Ligand-Dependent Oligomerization Of Ribonucleotide Reductase, Bill Pham

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Certain protein oligomerization can be strongly influenced by its ligand-binding status. We constructed a computational method to investigate how ligand-binding and oligomerization can be coupled. We tackle this issue using an approximate approach of studying the properties of individual monomers and how they associate. By connecting the dynamics at monomeric level and the information of oligomer interface, we quantify the synchronization of two types of contact dynamics: (1) between the ligand and its binding pocket, and (2) the contact dynamics at interface. In this work, we applied our methodology on protein ribonucleotide reductase (RNR), which is an essential enzyme for ...


Investigation Into The Amino Acid Characteristic Of Intrinsically Disordered Proteins, Samantha Patterson 2018 University of Wyoming

Investigation Into The Amino Acid Characteristic Of Intrinsically Disordered Proteins, Samantha Patterson

Honors Theses AY 17/18

Caulobacter crescentus, which belongs to the class of Alphaproteobacteria, has a highly organized cytoplasm that includes complex macromolecular structures at the cell poles. These polar complexes are assembled through the activity of a scaffolding protein, known as the Polar Organizing Protein Z (PopZ). PopZ interacts with other proteins via an N-terminal domain that is mostly intrinsically disordered, and contains, an abundance of proline, glutamte, and aspartate (P,E, and D) residues. Surprisingly, scrambling the order of amino acids in the PED region does not affect PopZ function, suggesting that binding affinity and specificity are not dependent on interactions with individual ...


State Dependent Function And Dynamics In Cerebral Cortical Networks, Leila Fakhraei 2018 University of Arkansas, Fayetteville

State Dependent Function And Dynamics In Cerebral Cortical Networks, Leila Fakhraei

Theses and Dissertations

Cerebral cortex exhibits vigorous ongoing, internal neural activity even with no sensory input is present or the animal is minimally engaged in a task or behavior. This internal ongoing activity is not static; the ‘cortical state’ varies ranging from synchronous and highly correlated activity to asynchronous and weakly correlated neural activity. The main goal of the work presented here is to understand how changes in cortical states effect several aspects of cortical function and dynamics.

To meet this goal, we did three separate projects. First, we compared the predictability of neuronal network dynamics across cortical states in somatosensory cortex of ...


Size Exclusion Chromatography Based Liposomal Protein Extraction (Selpe), Carolyn Barnes 2018 University of Tennessee-Knoxville

Size Exclusion Chromatography Based Liposomal Protein Extraction (Selpe), Carolyn Barnes

University of Tennessee Honors Thesis Projects

No abstract provided.


Cloning, Purification, And Preliminary Dna-Binding And Unfolding Results For The Dna Polymerase I From The Psychrophile Psychromonas Ingrahamii, John Tod Baker 2018 Louisiana State University and Agricultural and Mechanical College

Cloning, Purification, And Preliminary Dna-Binding And Unfolding Results For The Dna Polymerase I From The Psychrophile Psychromonas Ingrahamii, John Tod Baker

LSU Master's Theses

Psychromonas ingrahamii is a psychrophilic bacterium that lives in Arctic polar sea ice and grows at a temperature range of -12 to 10º C. This bacterium resides within veins inside the ice where the salinity is high, resulting in a freezing point depression and liquid water. The large fragment of DNA polymerase I from Psychromonas ingrahamii, called Klenpin, has been cloned, expressed, and purified in our laboratory. Although enzyme kinetic studies have been performed on a few psychrophilic enzymes, the thermodynamics of ligand binding and of protein stability have not been well studied for this class of extremophilic proteins. Here ...


Experiences Of The Breast Cancer Patients Undergoing Radiotherapy At A Public Hospital Peshawar Pakistan, Gulzar Habibullah, Raisa Raisa, Shanaz Hussein Cassum SC, Rehana Elahi 2018 Postgraduate College of Nursing Hayatabad, Peshawar, Pakistan

Experiences Of The Breast Cancer Patients Undergoing Radiotherapy At A Public Hospital Peshawar Pakistan, Gulzar Habibullah, Raisa Raisa, Shanaz Hussein Cassum Sc, Rehana Elahi

School of Nursing & Midwifery

Objective: This study aimed to explore the experiences of female breast cancer patients undergoing radiotherapy (RT) in a public hospital in Peshawar, Pakistan.
Methods: This study employed a descriptive exploratory method. A purposive sample of 14 breast cancer women undergoing RT was selected for this study. Data were collected over the period of 5 months, using a semi-structured interview guide and conducting in-depth face-to-face interviews. These interviews were audio taped and transcribed by a bilingual transcriber. The translated version of the interview was coded, and the analysis was done manually.
Results: Four main categories emerged from data analysis, which were ...


Ras Hyperactivation Versus Overexpression: Lessons From Ras Dynamics In Candida Albicans, Vavilala A. Pratyusha, Guiliana Soraya Victoria, Mohammad Firoz Khan, Dominic T. Haokip, Bhawna Yadav, Nibedita Pal, Subhash Chandra Sethi, Priyanka Jain, Sneh Lata Singh, Sobhan Sen, Sneha Sudha Komath 2018 Jawaharlal Nehru University

Ras Hyperactivation Versus Overexpression: Lessons From Ras Dynamics In Candida Albicans, Vavilala A. Pratyusha, Guiliana Soraya Victoria, Mohammad Firoz Khan, Dominic T. Haokip, Bhawna Yadav, Nibedita Pal, Subhash Chandra Sethi, Priyanka Jain, Sneh Lata Singh, Sobhan Sen, Sneha Sudha Komath

Open Access Articles

Ras signaling in response to environmental cues is critical for cellular morphogenesis in eukaryotes. This signaling is tightly regulated and its activation involves multiple players. Sometimes Ras signaling may be hyperactivated. In C. albicans, a human pathogenic fungus, we demonstrate that dynamics of hyperactivated Ras1 (Ras1G13V or Ras1 in Hsp90 deficient strains) can be reliably differentiated from that of normal Ras1 at (near) single molecule level using fluorescence correlation spectroscopy (FCS). Ras1 hyperactivation results in significantly slower dynamics due to actin polymerization. Activating actin polymerization by jasplakinolide can produce hyperactivated Ras1 dynamics. In a sterol-deficient hyperfilamentous GPI mutant of C ...


Thermodynamics In Large Hairpin Polyamide-Dna Interactions, Yang Song 2018 University of Missouri, St. Louis

Thermodynamics In Large Hairpin Polyamide-Dna Interactions, Yang Song

Dissertations

Human papillomavirus (HPV) is a common sexually transmitted virus responsible for cervical cancers, and its infection is currently incurable. Only a few vaccines against high-risk HPV strains are available. Hairpin polyamides (PAs) in different sizes (8-20 units long) bind DNA in different lengths. They have been shown to have different anti-HPV activities in cell culture.

The interaction between PA and DNA is stabilized by two types of molecular forces: attractive and repulsive forces. Attractive forces include hydrogen bonds, van der Waals contacts and electrostatic forces between PA and DNA. Repulsive forces include the hydrophobic effect, which forces the PA out ...


Investigating The Response Of Magnetotactic Bacteria To Varying Field Strength And Developing Autonomous Analysis Of Spatial Dispersal, Madeleine D. Pasco 2018 Rose-Hulman Institute of Technology

Investigating The Response Of Magnetotactic Bacteria To Varying Field Strength And Developing Autonomous Analysis Of Spatial Dispersal, Madeleine D. Pasco

Rose-Hulman Undergraduate Research Publications

Magnetotactic bacteria (MTB) are single-celled organisms which contain organelles called “magnetosomes,” membrane-bound ferrous nanocrystals. These organelles allow for magnetotaxis, which is movement guided by magnetic fields. MTB are generally found in the top layers of sediment of aqueous environments, and magnetotaxis is thought to help guide these microbes to ideal oxygen concentrations in the water after they may have been displaced by turbulent waters. In this we study the effect of the strength of a magnetic field on magnetotaxis.


Altering Oligomerization Of Epha2 Via Mutations In The Intracellular Domain, Ryan W. Lingerak 2018 The University of Akron

Altering Oligomerization Of Epha2 Via Mutations In The Intracellular Domain, Ryan W. Lingerak

Honors Research Projects

Eph receptor tyrosine kinases (RTKs) are activated by membrane-bound ligands called ephrins. Eph RTKs are divided into two subclasses, each activated by a specific classes of the ligand ephrin. The overexpression of Eph receptors is correlated to cancer cell metastasis in several different types of cancers. Studies with the EphA2 extracellular domain (ECD) and ephrinA1 ligand have shown that upon binding of ephrin to the receptor, EphA2 undergoes increased oligomerization and activation. This indicates that oligomerization is intimately connected to kinase activity. High resolution crystal structures of the EphA2 ECD have revealed some details of these ligand bound oligomers, as ...


Observing The Molecular Basis Of Thin Filament Activation With A Three Bead Laser Trap Assay, Thomas Longyear 2018 University of Massachusetts Amherst

Observing The Molecular Basis Of Thin Filament Activation With A Three Bead Laser Trap Assay, Thomas Longyear

Doctoral Dissertations

Muscle contracts after calcium (Ca++) is released into the muscle cell, resulting from a cascade of events which result in myosin, the molecular motor of muscle, to produce force and motion. Myosin cyclically binds to a regulated thin filament, using the chemical energy of ATP to produce force and motion. Perturbations in muscle, such as a build-up of metabolic by-products or point mutations in key contractile proteins, can inhibit these functions in both skeletal and cardiac muscle either acutely or chronically. Despite the many years we have studied skeletal and cardiac muscle, we still do not have a clear picture ...


Transport Of Charged Small Molecules After Electropermeabilization - Drift And Diffusion, Esin B. Sözer, C. Florencia Pocetti, P. Thomas Vernier 2018 Old Dominion University

Transport Of Charged Small Molecules After Electropermeabilization - Drift And Diffusion, Esin B. Sözer, C. Florencia Pocetti, P. Thomas Vernier

Bioelectrics Publications

Background: Applications of electric-field-induced permeabilization of cells range from cancer therapy to wastewater treatment. A unified understanding of the underlying mechanisms of membrane electropermeabilization, however, has not been achieved. Protocols are empirical, and models are descriptive rather than predictive, which hampers the optimization and expansion of electroporation-based technologies. A common feature of existing models is the assumption that the permeabilized membrane is passive, and that transport through it is entirely diffusive. To demonstrate the necessity to go beyond that assumption, we present here a quantitative analysis of the post-permeabilization transport of three small molecules commonly used in electroporation research-YO-PRO-1, propidium ...


Can A Comprehensive Transition Plan To Barefoot Running Be The Solution To The Injury Epidemic In American Endurance Runners?, Michael A. Scarlett 2018 Claremont McKenna College

Can A Comprehensive Transition Plan To Barefoot Running Be The Solution To The Injury Epidemic In American Endurance Runners?, Michael A. Scarlett

CMC Senior Theses

Fossils belonging to the genus Homo, dating as far back as two million years ago, exhibit uniquely efficient features suggesting that early humans had evolved to become exceptional endurance runners. Although they did not have the cushion or stability-control features provided in our modern day running shoes, our early human ancestors experienced far less of the running-related injuries we experience today. The injury rate has been estimated as high as 90% annually for Americans training for a marathon and as high as 79% annually for all American endurance runners. There is an injury epidemic in conventionally shod populations that does ...


Dynamic Control Of Particle Separation In Deterministic Lateral Displacement Separator With Viscoelastic Fluids, Yuke Li, Hongna Zhang, Yongyao Li, Xiaobin Li, Jian Wu, Shizhi Qian, Fengchen Li 2018 Old Dominion University

Dynamic Control Of Particle Separation In Deterministic Lateral Displacement Separator With Viscoelastic Fluids, Yuke Li, Hongna Zhang, Yongyao Li, Xiaobin Li, Jian Wu, Shizhi Qian, Fengchen Li

Mechanical & Aerospace Engineering Faculty Publications

We proposed an innovative method to achieve dynamic control of particle separation by employing viscoelastic fluids in deterministic lateral displacement (DLD) arrays. The effects of shear-thinning and elasticity of working fluids on the critical separation size in DLD arrays are investigated. It is observed that each effect can lead to the variation of the critical separation size by approximately 40%. Since the elasticity strength of the fluid is related to the shear rate, the dynamic control can for the first time be easily realized through tuning the flow rate in microchannels.


Modulation Of The Navigational Strategy Of Insects In Controlled Temperature Environments, Joseph Shomar, Anggie Ferrer, Josh Forer, Tom Zhang, Mason Klein 2018 University of Miami

Modulation Of The Navigational Strategy Of Insects In Controlled Temperature Environments, Joseph Shomar, Anggie Ferrer, Josh Forer, Tom Zhang, Mason Klein

2018 Entries

With its small size and limited motor tool set, the Drosophila larva is a good system to study how animals alter specific elements of their behavior to search and reach optimal environmental conditions. We aim to understand the larva’s response to temperature across development, in sensory gradients, and to distinguish behavioral modulations based on physical changes from those due to sensory input. PID-controlled instruments drive temporal or spatial temperature gradients; combined with a moat system to replenish gels at high temperature, we can explore the larva’s full behavioral profile. Many larvae are simultaneously observed during free navigation in ...


Confirmation That Mrub_1751 Is Homologous To E. Coli Xylf, Mrub_1752 Is Homologous To E. Coli Xylh, And Mrub_1753 Is Homologous To E. Coli Xylg, Ben Price, Dr. Lori Scott 2018 Augustana College, Rock Island Illinois

Confirmation That Mrub_1751 Is Homologous To E. Coli Xylf, Mrub_1752 Is Homologous To E. Coli Xylh, And Mrub_1753 Is Homologous To E. Coli Xylg, Ben Price, Dr. Lori Scott

Meiothermus ruber Genome Analysis Project

In this project we investigated the biological function of the genes Mrub_1751, Mrub_1752 and Mrub_1753 (KEGG map number 02010). We predict these genes encode components of a D-xylose ATP Binding Cassette (ABC) transporter: 1) Mrub_1752 (DNA coordinates 1809004-1810224 on the forward strand) encodes the permease component (aka transmembrane domain), predicted to be an ortholog and 2) Mrub_1753 (DNA coordinates 1810227-1811000 on the forward strand) encodes the ATP-binding domain (aka nucleotide binding domain); and 3) Mrub_1751 (DNA coordinates 1807855-1808892 on the forward strand) encodes the solute binding protein. The ABC-transporter for M. ruber to transport D-xylose is homologous with the transporter ...


Investigation Of Aminoglycoside Induced Nanoparticle Self-Assemblies, Michael Leong 2018 University of Central Florida

Investigation Of Aminoglycoside Induced Nanoparticle Self-Assemblies, Michael Leong

Honors in the Major Theses

Aminoglycosides are a group of broad-spectrum antibiotics that, under neutral pH conditions, carry a positive charge. The net cationic charge arises from the high number of amino groups in the core structure of aminoglycosides. Previous studies performed have shown that negatively charged citrate ligand-capped gold nanoparticles (AuNPs) can interact with various biomolecules such as aminoglycosides. AuNPs bound to biomolecules have been used in conjugation with various assaying techniques to detect and study compounds in vitro and in vivo. AuNPs also have strong light scattering properties that can be used with a wide variety of imaging and assaying techniques. Our laboratory ...


Evaluation Of Extracellular Matrix Composition And Rheology As Determinants Of Growth, Invasion, And Response To Photodynamic Therapy In 3d Cell Culture Models Of Pancreatic Ductal Adenocarcinoma, Gwendolyn M. Cramer 2017 University of Massachusetts Boston

Evaluation Of Extracellular Matrix Composition And Rheology As Determinants Of Growth, Invasion, And Response To Photodynamic Therapy In 3d Cell Culture Models Of Pancreatic Ductal Adenocarcinoma, Gwendolyn M. Cramer

Graduate Doctoral Dissertations

Pancreatic ductal adenocarcinoma (PDAC) is a notoriously lethal disease characterized by prominent stromal involvement, which plays complex roles in regulating tumor growth and therapeutic response. The extracellular matrix (ECM)-rich stroma has been implicated as a barrier to drug penetration, although stromal depletion strategies have had mixed clinical success. It remains less clear how biophysical interactions with the ECM regulate invasive progression and susceptibilities to specific therapies. Here, an integrative approach combining 3D cell culture and quantitative imaging techniques is used to evaluate invasive behavior and motility as determinants of response to classical chemotherapy and photodynamic therapy (PDT), in which ...


Developing Algorithms For Quantifying The Super Resolution Microscopic Data: Applications To The Quantification Of Protein-Reorganization In Bacteria Responding To Treatment By Silver Ions, Sai Divya Challapalli 2017 University of Arkansas, Fayetteville

Developing Algorithms For Quantifying The Super Resolution Microscopic Data: Applications To The Quantification Of Protein-Reorganization In Bacteria Responding To Treatment By Silver Ions, Sai Divya Challapalli

Theses and Dissertations

Histone-like nucleoid structuring proteins (HNS) play significant roles in shaping the chromosomal DNA, regulation of transcriptional networks in microbes, as well as bacterial responses to environmental changes such as temperature fluctuations. In this work, the intracellular organization of HNS proteins in E. coli bacteria was investigated utilizing super-resolution fluorescence microscopy, which surpasses conventional microscopy by 10–20 fold in spatial resolution. More importantly, the changes of the spatial distribution of HNS proteins in E. coli, by addition of silver ions into the growth medium were explored. To quantify the spatial distribution of HNS in bacteria and its changes, an automatic ...


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