Neurophysiological Impact And Modeling-Independent Elucidation Of Inactivation Pathways In A-Type K+ Channels, 2012 Thomas Jefferson University
Neurophysiological Impact And Modeling-Independent Elucidation Of Inactivation Pathways In A-Type K+ Channels, J.D. Fineberg, David Ritter, Manuel Covarrubias
Department of Molecular Physiology and Biophysics Faculty Papers
Poster presented at Society for Neuroscience
Abstract:
A-type voltage-gated K+ channels auto-regulate their function by undergoing fast inactivation. Independent of molecular mechanisms, this inactivation can proceed after channel opening (open-state inactivation, OSI) or from a closed state prior to opening (closed-state inactivation, CSI). We hypothesize that the specific neurophysiological roles of A-type Kv channels depend on whether they undergo OSI, CSI or both (CSI+OSI). To explore these possibilities, we introduced Markov kinetic schemes of the A-type Kv4 conductance into a computational model of the hippocamcal CA1 neuron assuming either CSI or CSI+OSI and compared the properties of the somatic …
Mcnamara 20120831fri-20120904tue Cosmic Ray Particles By Ccd Imaging, 2012 M.D. Anderson Cancer Center
Mcnamara 20120831fri-20120904tue Cosmic Ray Particles By Ccd Imaging, George Mcnamara
George McNamara
McNamara 20120831Fri-20120904Tue Cosmic Ray Particles by CCD imaging.zip contains image files in support of a Microscopy Today article - please see
http://www.microscopy-today.com/
Hyperpolarized 3he And 129xe Mr Imaging In Healthy Volunteers And Patients With Chronic Obstructive Pulmonary Disease, 2012 Western University
Hyperpolarized 3he And 129xe Mr Imaging In Healthy Volunteers And Patients With Chronic Obstructive Pulmonary Disease, Miranda Kirby, Sarah Svenningsen, Amir Owrangi, Andrew Wheatley, Adam Farag, Alexei Ouriadov, Giles E Santyr, Roya Etemad-Rezai, Harvey O Coxson, David G Mccormack, Grace Parraga
Medical Biophysics Publications
PURPOSE: To quantitatively compare hyperpolarized helium 3 (3He) and xenon 129 (129Xe) magnetic resonance (MR) images obtained within 5 minutes in healthy volunteers and patients with chronic obstructive pulmonary disease (COPD) and to evaluate the correlations between 3He and 129Xe MR imaging measurements and those from spirometry and plethysmography.
MATERIALS AND METHODS: This study was approved by an ethics board and compliant with HIPAA. Written informed consent was obtained from all subjects. Eight healthy volunteers and 10 patients with COPD underwent MR imaging, spirometry, and plethysmography. Ventilation defect percentages (VDPs) at 3He and 129Xe imaging were obtained by using semiautomated …
What Can Computed Tomography And Magnetic Resonance Imaging Tell Us About Ventilation?, 2012 Western University
What Can Computed Tomography And Magnetic Resonance Imaging Tell Us About Ventilation?, Brett A Simon, David W Kaczka, Alexander A Bankier, Grace Parraga
Medical Biophysics Publications
This review provides a summary of pulmonary functional imaging approaches for determining pulmonary ventilation, with a specific focus on multi-detector x-ray computed tomography and magnetic resonance imaging (MRI). We provide the important functional definitions of pulmonary ventilation typically used in medicine and physiology and discuss the fact that some of the imaging literature describes gas distribution abnormalities in pulmonary disease that may or may not be related to the physiological definition or clinical interpretation of ventilation. We also review the current state-of-the-field in terms of the key physiological questions yet unanswered related to ventilation and gas distribution in lung disease. …
Cosmic Ray Particles Images With Orca-Ii Erg, 2012 M.D. Anderson Cancer Center
Cosmic Ray Particles Images With Orca-Ii Erg, George Mcnamara
George McNamara
Cosmic ray particles image series acquired using a Hamamatsu ORCA-II ERG scientific grade CCD camera, cooled to -60 C. Each image is a consecutive 600 second (10 minute) exposure time with no light to the camera.
While processing the data, I discoverd that the background changed around planes 25 and 227 (see Excel file and jpeg screenshots), so I also processed only planes 025-227 (203 planes total, 2030 minutes, 33.83 hours). the CCD industry "rule of thumb" for a "typical" CCD sensor (i.e. 1/3" CCD) is that one cosmic ray particle strikes a sensor approximately every 30 seconds (assuming not …
Shift Work And Vascular Events: Systematic Review And Meta-Analysis., 2012 Western University
Shift Work And Vascular Events: Systematic Review And Meta-Analysis., Manav V Vyas, Amit X Garg, Arthur V Iansavichus, John Costella, Allan Donner, Lars E Laugsand, Imre Janszky, Marko Mrkobrada, Grace Parraga, Daniel G Hackam
Medical Biophysics Publications
OBJECTIVE: To synthesise the association of shift work with major vascular events as reported in the literature.
DATA SOURCES: Systematic searches of major bibliographic databases, contact with experts in the field, and review of reference lists of primary articles, review papers, and guidelines.
STUDY SELECTION: Observational studies that reported risk ratios for vascular morbidity, vascular mortality, or all cause mortality in relation to shift work were included; control groups could be non-shift ("day") workers or the general population.
DATA EXTRACTION: Study quality was assessed with the Downs and Black scale for observational studies. The three primary outcomes were myocardial infarction, …
The Role Of Amino-Terminal In Determining Transjunctional Voltage-Dependent Gating And Unitary Conductance Of Cx36 And Cx50 Gap Junction Channels, 2012 The University of Western Ontario
The Role Of Amino-Terminal In Determining Transjunctional Voltage-Dependent Gating And Unitary Conductance Of Cx36 And Cx50 Gap Junction Channels, Li Xin
Electronic Thesis and Dissertation Repository
Gap junction (GJ) channels directly connect the cytoplasm of neighboring cells, and allow for the transfer of ions and small molecules between two cells. GJ channels are known to be gated by the transjunctional voltage (Vj, the voltage difference between the interiors of adjoining cells), which is referred to as Vj-dependent gating. GJ channels show varying degrees of sensitivity to Vj, depending on the type of connexin(s) comprising the GJ channel. GJ channels formed by different connexins also show unique unitary conductance ranging from ~ 10 pS to ~300 pS. However, the molecular structures …
Stereotactic Ablative Radiotherapy For Comprehensive Treatment Of Oligometastatic Tumors (Sabr-Comet): Study Protocol For A Randomized Phase Ii Trial., 2012 University of Western Ontario
Stereotactic Ablative Radiotherapy For Comprehensive Treatment Of Oligometastatic Tumors (Sabr-Comet): Study Protocol For A Randomized Phase Ii Trial., Michael Lock
Michael Lock
No abstract provided.
Radiation Dose Distributions In Three Dimensions From Tomographic Optical Density Scanning Of Polymer Gels: Ii. Optical Properties Of The Bang Polymer Gel, 2012 Olin College of Engineering
Radiation Dose Distributions In Three Dimensions From Tomographic Optical Density Scanning Of Polymer Gels: Ii. Optical Properties Of The Bang Polymer Gel, Yevgeniya Zastavker, Marek Maryanski, John Gore
Yevgeniya V. Zastavker
A newly developed method of radiation dosimetry makes use of the optical properties of polymer gels. The dose-response mechanism relies on the production of light-scattering polymer micro-particles in the gel at each site of radiation absorption. The scattering produces an attenuation of transmitted light intensity that is directly related to the dose and independent of dose rate. For the BANG polymer gel (bis, acrylamide, nitrogen, and gelatin) the shape of the dose-response curve depends on the fraction of the cross-linking monomer in the initial mixture and on the wavelength of light. At 500 nm the attenuation coefficient (μ) increases by …
Male Breast Cancer, 2012 University of Western Ontario
Mri-Based Attenuation Correction In Emission Computed Tomography, 2012 The University of Western Ontario
Mri-Based Attenuation Correction In Emission Computed Tomography, Harry R. Marshall
Electronic Thesis and Dissertation Repository
The hybridization of magnetic resonance imaging (MRI) with positron emission tomography (PET) or single photon emission computed tomography (SPECT) enables the collection of an assortment of biological data in spatial and temporal register. However, both PET and SPECT are subject to photon attenuation, a process that degrades image quality and precludes quantification. To correct for the effects of attenuation, the spatial distribution of linear attenuation coefficients (μ-coefficients) within and about the patient must be available. Unfortunately, extracting μ-coefficients from MRI is non-trivial. In this thesis, I explore the problem of MRI-based attenuation correction (AC) in emission tomography.
In particular, I …
Improved Techniques For Acquisition And Analysis Of Dynamic Contrast-Enhanced Magnetic Resonance Imaging For Detecting Vascular Permeability In The Central Nervous System, 2012 The University of Texas Graduate School of Biomedical Sciences at Houston
Improved Techniques For Acquisition And Analysis Of Dynamic Contrast-Enhanced Magnetic Resonance Imaging For Detecting Vascular Permeability In The Central Nervous System, Cheukkai Hui
Dissertations & Theses (Open Access)
Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is a noninvasive technique for quantitative assessment of the integrity of blood-brain barrier and blood-spinal cord barrier (BSCB) in the presence of central nervous system pathologies. However, the results of DCE-MRI show substantial variability. The high variability can be caused by a number of factors including inaccurate T1 estimation, insufficient temporal resolution and poor contrast-to-noise ratio. My thesis work is to develop improved methods to reduce the variability of DCE-MRI results. To obtain fast and accurate T1 map, the Look-Locker acquisition technique was implemented with a novel and truly centric k-space segmentation scheme. In …
Assessment Of Wear In Total Knee Arthroplasty Using Advanced Radiographic Techniques, 2012 The University of Western Ontario
Assessment Of Wear In Total Knee Arthroplasty Using Advanced Radiographic Techniques, Matthew G. Teeter
Electronic Thesis and Dissertation Repository
Total knee arthroplasty (TKA) has become the gold standard approach for treating advanced osteoarthritis of the knee. Although the surgery continues to be very successful at relieving pain and restoring joint function, its longevity is challenged by wear and loosening of the implant components. This requires the patient to undergo a revision surgery to replace the implant, a much more challenging operation than primary arthroplasty. Wear of the polyethylene tibial inserts from TKA is assessed in vitro using mechanical wear simulator testing and by examining failed implants retrieved from patients during revision surgery, as well as with direct in vivo …
Hearts And Minds: Examining The Evolution Of The Egyptian Excerebration And Evisceration Traditions Through The Impact Mummy Database, 2012 The University of Western Ontario
Hearts And Minds: Examining The Evolution Of The Egyptian Excerebration And Evisceration Traditions Through The Impact Mummy Database, Andrew D. Wade
Electronic Thesis and Dissertation Repository
Egyptian mummification and funerary rituals were a transformative process, making the deceased a pure being; free of disease, injury, and disfigurements, as well as ethical and moral impurities. Consequently, the features of mummification available to specific categories of individuals hold social and ideological significance. This study refutes long-held classical stereotypes, particularly dogmatic class associations; demonstrates the apocryphal nature of universal heart retention; and expands on the purposes of excerebration and evisceration implied by synthetic and radiological analyses.
Features of the embalming traditions, specifically the variable excerebration and evisceration traditions, represented the Egyptian view of death. Fine-grain analyses, through primary imaging …
Modeling Oxygen Transport In Three-Dimensional Capillary Networks, 2012 The University of Western Ontario
Modeling Oxygen Transport In Three-Dimensional Capillary Networks, Graham M. Fraser
Electronic Thesis and Dissertation Repository
The purpose of this thesis was to examine how the use of real 3-dimensional (3D) capillary network geometries affect models of oxygen transport to tissue. Software was developed to reconstruct microvascular geometry in 3D from intravital video. Characterization of 3D reconstructions demonstrated that capillary density, length and capillary diameter were consistent with previous findings. Using reconstructed capillary networks a strategy was devised that utilized red blood cell (RBC) supply rate (SR) as a metric for flow modeling. Applying the RBC SR based flow model on baseline and perturbed flow conditions demonstrated that RBC SR is a major determinant of oxygen …
Quantitative Pulmonary Imaging Using Computed Tomography And Magnetic Resonance Imaging, 2012 Western University
Quantitative Pulmonary Imaging Using Computed Tomography And Magnetic Resonance Imaging, George R Washko, Grace Parraga, Harvey O Coxson
Medical Biophysics Publications
Measurements of lung function, including spirometry and body plethesmography, are easy to perform and are the current clinical standard for assessing disease severity. However, these lung functional techniques do not adequately explain the observed variability in clinical manifestations of disease and offer little insight into the relationship of lung structure and function. Lung imaging and the image-based assessment of lung disease has matured to the extent that it is common for clinical, epidemiologic and genetic investigation to have a component dedicated to image analysis. There are several exciting imaging modalities currently being used for the non-invasive study of lung anatomy …
Flatbed Scanner Report - Optical Density Dynamic Range, 2012 M.D. Anderson Cancer Center
Flatbed Scanner Report - Optical Density Dynamic Range, George Mcnamara
George McNamara
George McNamara (now at University of Miami) report for Hua Yu and Richard Jove, City of Hope National Medical Center, on optical density dynamic range of several flatbed scanners.
Introduction To Nanoscopy Nano-Talk, 2012 M.D. Anderson Cancer Center
Introduction To Nanoscopy Nano-Talk, George Mcnamara
George McNamara
T7-1 is the designation for the LMRG Nanoscopy session at ABRF in Orlando, FL, on March 20, 2012. The PDF file here is a draft of my presentation.
May not be very helpful since (1) would probably help to know what is in my head and each slide will [hopefully] prompt me to say, and (2) 10 minute talk so I am going to push the "next slide" button after saying very little.
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Publisher statement:
The T7-1 Introduction to Nanoscopy Nano Talk is copyrighted (c) George McNamara, 2012. Except for (1) screenshots from research articles (which are copyrighted by …
Pubspectra - Open Data Access Fluorescence Spectra, 2012 M.D. Anderson Cancer Center
Pubspectra - Open Data Access Fluorescence Spectra, George Mcnamara
George McNamara
The Internet is enabling greater access to spectral imaging publications, spectral graphs, and data than that was available a generation ago. The spectral imaging systems discussed in this issue of Cytometry work because reagent and hardware spectra are reproducible, reusable, and provide input to spectral unmixing and spectral components recognition algorithms. These spectra need to be readily available in order to determine what to purchase, how to use it, and what the output means. We refer to several commercially sponsored and academic spectral web sites and discuss our spectral graphing and data sites. Sites include fluorescent dye graph servers from …
Mcnamara 2011 Feature Extraction (Image Analysis), 2012 M.D. Anderson Cancer Center
Mcnamara 2011 Feature Extraction (Image Analysis), George Mcnamara
George McNamara
Feature Extraction presentation and movies in a ZIP file from a presentation I gave at ISAC 2011 in Baltomore, Md.
Feature extraction is one phrase for image analysis.