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Brain-Computer Interfaces Using Electrocorticography And Surface Stimulation, Jesse Wheeler 2018 Washington University in St. Louis

Brain-Computer Interfaces Using Electrocorticography And Surface Stimulation, Jesse Wheeler

Engineering and Applied Science Theses & Dissertations

The brain connects to, modulates, and receives information from every organ in the body. As such, brain-computer interfaces (BCIs) have vast potential for diagnostics, medical therapies, and even augmentation or enhancement of normal functions. BCIs provide a means to explore the furthest corners of what it means to think, to feel, and to act—to experience the world and to be who you are. This work focuses on the development of a chronic bi-directional BCI for sensorimotor restoration through the use of separable frequency bands for recording motor intent and providing sensory feedback via electrocortical stimulation. Epidural cortical surface electrodes ...


Gq Noncanonical Roles In Translational Regulation, Brett DeMarco 2018 Duquesne University

Gq Noncanonical Roles In Translational Regulation, Brett Demarco

Electronic Theses and Dissertations

This study investigates protein nucleic acid interactions, focusing on G-quadruplex (GQ) forming DNA/RNA in human disease. GQ structures are formed in DNA/RNA, when four guanine residues form planar tetrads stabilized by Hoogsteen base pairing, that stack forming a GQ structure stabilized by potassium ions. These GQ structures are targeted by the arginine glycine-glycine (RGG) RNA-binding domain. Fragile X mental retardation protein (FMRP), a translation regulator protein implicated in the fragile X syndrome, has an RGG domain and has been previously shown to interact with neuronal GQ forming messenger RNA (mRNA). We have investigated three neuronal FMRP mRNA targets ...


Characterization Of A Variant Of Tuberous Sclerosis Complex 2 And Its Interaction With Rheb, Sowmya Sivakumar 2018 University of Arkansas, Fayetteville

Characterization Of A Variant Of Tuberous Sclerosis Complex 2 And Its Interaction With Rheb, Sowmya Sivakumar

Theses and Dissertations

Protein-protein interactions are vital in maintaining proper function and homeostasis in cells. Some signaling pathways are regulated by G-proteins that work like switches to activate and deactivate pathways. Mutations in these proteins, their effectors or the interaction between proteins may cause dysregulation of signals that can lead to many diseases.

Rheb, Ras homology enriched in brain, is a Ras family GTPase that is vital in regulation of the mTOR (mammalian target of rapamycin) pathway that signals cell proliferation and growth. Due to the low intrinsic GTPase activity of Rheb, a GTPase activating protein (GAP), Tuberous Sclerosis Complex 2 (TSC2) down ...


Activities And Classroom Demonstrations In Biological Physics: A Resource Document, Philip C. Nelson, William Berner 2018 University of Pennsylvania

Activities And Classroom Demonstrations In Biological Physics: A Resource Document, Philip C. Nelson, William Berner

Department of Physics Papers

We give detailed recipes for a number of classroom demonstrations relevant to biological physics instruction. We developed them mainly for use in 2nd-3rd year undergraduate Physics courses. But you can (and we do) use them for primary school, through high school, up to PhD candidates. You adapt the words for each audience, but a phenomenon is a phenomenon.

We also outline a 1-hour introduction to Python for undergraduate scientific computing.

Finally we document some outcomes from courses taught at U Pennsylvania using these resources and others cited here. This material was presented at a workshop at the AAPT meeting in ...


Developing Droplet Based 3d Cell Culture Methods To Enable Investigations Of The Chemical Tumor Microenvironment, Jacqueline A. De Lora 2018 University of New Mexico - Main Campus

Developing Droplet Based 3d Cell Culture Methods To Enable Investigations Of The Chemical Tumor Microenvironment, Jacqueline A. De Lora

Biomedical Sciences ETDs

Adaptation of cancer cells to changes in the biochemical microenvironment in an expanding tumor mass is a crucial aspect of malignant progression, tumor metabolism, and drug efficacy. In vitro, it is challenging to mimic the evolution of biochemical gradients and the cellular heterogeneity that characterizes cancer tissues found in vivo. It is well accepted that more realistic and controllable in vitro 3D model systems are required to improve the overall cancer research paradigm and thus improve on the translation of results, but multidisciplinary approaches are needed for these advances. This work develops such approaches and demonstrates that new droplet-based cell-encapsulation ...


Study Of The Visual Adaptation Mechanism In Marine Species With The Change Of Habitation Depth., Demid Osipov, Daniil Moshnikov 2018 Physical-Technical High School

Study Of The Visual Adaptation Mechanism In Marine Species With The Change Of Habitation Depth., Demid Osipov, Daniil Moshnikov

The International Student Science Fair 2018

The goal of our work was to determine the principal mechanisms that provide the difference in visual perception of two marine species that live on different depths: T. Pacificus and O. Vulgaris. In nature, visual perception of species that live deeper is shifted towards the blue region. This is related to the fact that red, orange and yellow light is absorbed more strongly by water than the blue light. On the other hand, the visual perception spectrum of an animal is determined by the absorption spectrum of the "light sensor" located in rods and cones of its eye retina. These ...


Synergistic Assembly Of Human Pre-Spliceosomes Across Introns And Exons, Joerg E. Braun, Larry J. Friedman, Jeff Gelles, Melissa J. Moore 2018 University of Massachusetts Medical School

Synergistic Assembly Of Human Pre-Spliceosomes Across Introns And Exons, Joerg E. Braun, Larry J. Friedman, Jeff Gelles, Melissa J. Moore

RNA Therapeutics Institute Publications

Most human genes contain multiple introns, necessitating mechanisms to effectively define exons and ensure their proper connection by spliceosomes. Human spliceosome assembly involves both cross-intron and cross-exon interactions, but how these work together is unclear. We examined in human nuclear extracts dynamic interactions of single pre-mRNA molecules with individual fluorescently tagged spliceosomal subcomplexes to investigate how cross-intron and cross-exon processes jointly promote pre-spliceosome assembly. U1 subcomplex bound to the 5' splice site of an intron acts jointly with U1 bound to the 5' splice site of the next intron to dramatically increase the rate and efficiency by which U2 subcomplex ...


Dynamics Of Human Protein Kinase Aurora A Linked To Drug Selectivity, Warintra Pitsawong, Vanessa Buosi, Renee Otten, Roman V. Agafonov, Adelajda Zorba, Nadja Kern, Steffen Kutter, Gunther Kern, Ricardo Ap Padua, Xavier Meniche, Dorothee Kern 2018 Brandeis University

Dynamics Of Human Protein Kinase Aurora A Linked To Drug Selectivity, Warintra Pitsawong, Vanessa Buosi, Renee Otten, Roman V. Agafonov, Adelajda Zorba, Nadja Kern, Steffen Kutter, Gunther Kern, Ricardo Ap Padua, Xavier Meniche, Dorothee Kern

Open Access Articles

Protein kinases are major drug targets, but the development of highly-selective inhibitors has been challenging due to the similarity of their active sites. The observation of distinct structural states of the fully-conserved Asp-Phe-Gly (DFG) loop has put the concept of conformational selection for the DFG-state at the center of kinase drug discovery. Recently, it was shown that Gleevec selectivity for the Tyr-kinase Abl was instead rooted in conformational changes after drug binding. Here, we investigate whether protein dynamics after binding is a more general paradigm for drug selectivity by characterizing the binding of several approved drugs to the Ser/Thr-kinase ...


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 ...


Synthesizing A Biomimetic Model Of The Mo-Cu Catalytic Site Of Carbon Monoxide Dehydrogenase, Ethan F. Gladhill 2018 Whitman College

Synthesizing A Biomimetic Model Of The Mo-Cu Catalytic Site Of Carbon Monoxide Dehydrogenase, Ethan F. Gladhill

Honors Theses

The carbon monoxide dehydrogenase in Oligotropha carboxidovorans is a molybdenum containing metalloenzyme that catalyzes the formation of carbon dioxide, two protons, and two electrons from carbon monoxide and water. This enzyme in soil bacteria remediates about 10-25 % of atmospheric carbon monoxide annually. However, our understanding of the CO oxidation of this enzyme is still incomplete. Previous efforts have been made to synthesize biomimetic models based on the active site of this enzyme. These efforts have yielded models that mimic portions of the catalytic site but lack both a mimicry of the entire site and catalytic activity. The reaction catalyzed by ...


Phosphorylation And Ubiquitination Events In The Regulation Of Gap Junction Protein Connexin 43, Rachel Margraf 2018 Lehigh University

Phosphorylation And Ubiquitination Events In The Regulation Of Gap Junction Protein Connexin 43, Rachel Margraf

Eckardt Scholars Projects

Connexin 43 (Cx43) accrual and removal from gap junctions is a complex progress regulated by specific phosphorylations, ubiquitinations and binding and release of regulatory proteins on the C- terminal tail of Cx43. In Thévenin & Margraf et al., 2017, our lab showed that specific phosphorylations on the C-terminal tail of Cx43 occur before and after the binding and release of the scaffold protein Zona Occludens-1 (ZO-1). In Kells-Andrews & Margraf et al., 2018 we show that K63-poly-ubiquitination occurs on residues K264 and K303 of the Cx43 C-terminal tail. This undergraduate thesis summarizes the immunofluorescence imaging and quantification I have contributed to ...


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.


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 ...


Biochemical Techniques For The Study Of Voltage-Gated Sodium Channel Auxiliary Subunits, Steven Molinarolo 2018 University of Iowa

Biochemical Techniques For The Study Of Voltage-Gated Sodium Channel Auxiliary Subunits, Steven Molinarolo

Theses and Dissertations

Voltage-gated sodium channels auxiliary subunits evolutionary emerged nearly 500 million years ago during the Cambrian explosion. These subunits alter one the most important ion channels to electrical signaling, the voltage-gated sodium channels support the propagation of electric impulses in animals. The mechanism for the auxiliary subunits effects on the channels is poorly understand, as is the stoichiometry between the auxiliary subunit and the channel. The focus of my thesis is to generate assays and to use these approaches to understand the interactions different types of voltage-gated channels and their auxiliary subunits. A biochemical approach was taken to identify novel interactions ...


Photonic Tools For Advanced Sensing And Imaging At The Nanoscale., Jafar Hamed Ghithan 2018 University of Louisville

Photonic Tools For Advanced Sensing And Imaging At The Nanoscale., Jafar Hamed Ghithan

Electronic Theses and Dissertations

This dissertation reports a novel bio-sensing strategy based on single-mode, electro-active, integrated optical waveguide (SM-EA-IOW) platforms. It also reports the development of a super-resolved far-field optical imaging tool to enable optical, electronic, and spectroelectrochemical investigations at the nanoscale. SM-EA-IOW platforms with its outstanding sensitivity for spectroelectrochemical interrogation was combined with a sandwich bioassay for the development of a novel immunosensing based strategy for label-free detection of infectious pathogens. The strategy begins with the functionalization of the electroactive waveguide surface with a capturing antibody aimed at a specific target analyte. Once the target analyte is bound to the photonic interface, it ...


Precision Health And Deafness–Optimizing Genetic Diagnosis, Christina Marie Sloan-Heggen 2018 University of Iowa

Precision Health And Deafness–Optimizing Genetic Diagnosis, Christina Marie Sloan-Heggen

Theses and Dissertations

Deafness is the most common sensory deficit in humans. In the United States 1-2 in a thousand babies is born with significant deafness, well over half of which is hereditary. Providing a patient and their family with a genetic diagnosis is the ultimate form of precision health and medicine; it can provide education, impact medical testing and treatment, provide peace of mind, and someday will be the key to providing gene specific therapies. Historically, providing this diagnosis was difficult, expensive, and time consuming due to the extreme clinical and genetic heterogeneity of non-syndromic hearing loss (NSHL).

Targeted genomic enrichment and ...


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 ...


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