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Estimation Of Differential Pathlength Factor From Nirs Measurement In Skeletal Muscle, B. Koirala, A. Concas, A. Cincotti, Yi Sun, A. Hernández, M. L. Goodwin, L. B. Gladden, N. Lai Jan 2024

Estimation Of Differential Pathlength Factor From Nirs Measurement In Skeletal Muscle, B. Koirala, A. Concas, A. Cincotti, Yi Sun, A. Hernández, M. L. Goodwin, L. B. Gladden, N. Lai

Electrical & Computer Engineering Faculty Publications

The utilization of continuous wave (CW) near-infrared spectroscopy (NIRS) device to measure non-invasively muscle oxygenation in healthy and disease states is limited by the uncertainties related to the differential path length factor (DPF). DPF value is required to quantify oxygenated and deoxygenated heme groups' concentration changes from measurement of optical densities by NIRS. An integrated approach that combines animal and computational models of oxygen transport and utilization was used to estimate the DPF value in situ. The canine model of muscle oxidative metabolism allowed measurement of both venous oxygen content and tissue oxygenation by CW NIRS under different oxygen delivery …


Lateralizing Ability Of Magnetic Resonance Spectroscopy And Diffusion Tensor Imaging In Temporal Lobe Epilepsy, Rasha Ali El-Kapany, Ibrahim Al-Sayed Al-Ahmar, Mona Sabry Elkholy, Rasha Abdelhafiz Aly, Ahmed Ali Saad Ali Hassan May 2023

Lateralizing Ability Of Magnetic Resonance Spectroscopy And Diffusion Tensor Imaging In Temporal Lobe Epilepsy, Rasha Ali El-Kapany, Ibrahim Al-Sayed Al-Ahmar, Mona Sabry Elkholy, Rasha Abdelhafiz Aly, Ahmed Ali Saad Ali Hassan

Menoufia Medical Journal

Background: Temporal lobe epilepsy (TLE) is the most common type of intractable and partial epilepsies. The only standard treatment for seizure-free status with manifest TLE is surgical which includes amygdala-hippocampectomy. The majority of temporal lobe seizures originate in the mesial temporal structures, primarily in the hippocampus, para hippocampal gyrus and amygdala.

Objectives: To compare lateralizing ability of Magnetic resonance spectroscopy and Diffusion tensor imaging in patients with temporal lobe epilepsy.

Methods: The study recruited 50 participant assigned into two groups: the first group included 25 epileptic cases and the second group included 25normal controls. Age showed a mean ± SD …


Estimation Of Free Water-Corrected Microscopic Fractional Anisotropy., Nico J J Arezza, Tales Santini, Mohammad Omer, Corey A Baron Jan 2023

Estimation Of Free Water-Corrected Microscopic Fractional Anisotropy., Nico J J Arezza, Tales Santini, Mohammad Omer, Corey A Baron

Medical Biophysics Publications

Water diffusion anisotropy MRI is sensitive to microstructural changes in the brain that are hallmarks of various neurological conditions. However, conventional metrics like fractional anisotropy are confounded by neuron fiber orientation dispersion, and the relatively low resolution of diffusion-weighted MRI gives rise to significant free water partial volume effects in many brain regions that are adjacent to cerebrospinal fluid. Microscopic fractional anisotropy is a recent metric that can report water diffusion anisotropy independent of neuron fiber orientation dispersion but is still susceptible to free water contamination. In this paper, we present a free water elimination (FWE) technique to estimate microscopic …


Synthesis Of Alginate/Hydroxyapatite Beads For Acetaminophen Delivery, Anesylvia Angan, Nonni Soraya Sambudi Sep 2022

Synthesis Of Alginate/Hydroxyapatite Beads For Acetaminophen Delivery, Anesylvia Angan, Nonni Soraya Sambudi

Makara Journal of Science

Conventional drug delivery systems usually involve the intake of multiple drugs, which could amplify the risk of overdosing. Acetaminophen is a widely used pain relief substance that is prone to accidental overdosing. Hence, a controlled drug delivery system is needed to ensure its efficacy. A nanocomposite hydroxyapatite/alginate system that was used as a drug carrier for acetaminophen was synthesized through the sol-gel method, and the mechanism underlying its controlled drug delivery was investigated. Spherical nanocomposite bead samples were synthesized by incorporating 5 wt%, 10 wt%, and 15 wt% hydroxyapatite into mixtures containing alginate. The mixtures were then dropped into calcium …


Examining The Association Between Brain Mri Measures At 7 Tesla And Cognition Following Covid-19 Infection, Helma Heidari Jul 2022

Examining The Association Between Brain Mri Measures At 7 Tesla And Cognition Following Covid-19 Infection, Helma Heidari

Electronic Thesis and Dissertation Repository

The long-term neuropsychological, cognitive, and neurobiological effects of the severe acute respiratory syndrome (SARS-CoV-2) in survivors with milder symptoms are still poorly understood. In this thesis we evaluated cognitive and psychological changes approximately five weeks after a wide range of symptoms in COVID-19 illness and determined whether advanced diffusion magnetic resonance imaging measures within subcortical brain structures of the limbic system were related to neurological, respiratory, psychiatric, and gastric symptoms experienced during the acute phase of illness. Cognitive and neuropsychological evaluations were performed in 45 participants who experienced neurological symptoms during the acute phase of COVID-19 illness. Participants also underwent …


Accuracy And Reliability Of Diffusion Imaging Models, Nicole A. Seider, Babatunde Adeyemo, Ryland Miller, Dillan J. Newbold, Jacqueline M. Hampton, Kristen M. Scheidter, Jerrel Rutlin, Timothy O. Laumann, Jarod L. Roland, David F. Montez, Andrew N. Van, Annie Zheng, Scott Marek, Benjamin P. Kay, G. Larry Bretthorst, Yong Wang, Steven E. Petersen, Deanna M. Barch, Evan M. Gordon, Abraham Z. Snyder, Joshua S. Shimony, Nico U. F. Dosenbach Jul 2022

Accuracy And Reliability Of Diffusion Imaging Models, Nicole A. Seider, Babatunde Adeyemo, Ryland Miller, Dillan J. Newbold, Jacqueline M. Hampton, Kristen M. Scheidter, Jerrel Rutlin, Timothy O. Laumann, Jarod L. Roland, David F. Montez, Andrew N. Van, Annie Zheng, Scott Marek, Benjamin P. Kay, G. Larry Bretthorst, Yong Wang, Steven E. Petersen, Deanna M. Barch, Evan M. Gordon, Abraham Z. Snyder, Joshua S. Shimony, Nico U. F. Dosenbach

2020-Current year OA Pubs

Diffusion imaging aims to non-invasively characterize the anatomy and integrity of the brain's white matter fibers. We evaluated the accuracy and reliability of commonly used diffusion imaging methods as a function of data quantity and analysis method, using both simulations and highly sampled individual-specific data (927-1442 diffusion weighted images [DWIs] per individual). Diffusion imaging methods that allow for crossing fibers (FSL's BedpostX [BPX], DSI Studio's Constant Solid Angle Q-Ball Imaging [CSA-QBI], MRtrix3's Constrained Spherical Deconvolution [CSD]) estimated excess fibers when insufficient data were present and/or when the data did not match the model priors. To reduce such overfitting, we developed …


A Detailed Parameter Study Into The Dermal Absorption Of Chemical Warfare Agents And The Effects Of Pharmacokinetics, Koko Lear May 2022

A Detailed Parameter Study Into The Dermal Absorption Of Chemical Warfare Agents And The Effects Of Pharmacokinetics, Koko Lear

Theses

Chemical warfare agents (CWAs) are substances of varying toxicity profiles. These chemicals exhibit complex dynamics and pose a serious health risk when released into the environment. A mathematical model based on Fick’s second law of diffusion was developed to comprehend how these compounds were absorbed into the skin. The analysis applied to both small and large doses and, successfully, predicted experimental results. This work also includes the effects of CWA physicochemical properties on evaporation and dermal absorption through the stratum corneum. A sensitivity analysis was conducted to assess the impacts of small variations in the initial dose, environmental conditions, and …


Adoption And Diffusion Of At-Home Medical Tests, Savannah Campbell, Mark Mitchell, Jerome Christia, Melissa Clark Jan 2022

Adoption And Diffusion Of At-Home Medical Tests, Savannah Campbell, Mark Mitchell, Jerome Christia, Melissa Clark

Atlantic Marketing Journal

The purpose of this study is to understand the at-home medical test market including the medical and regulatory requirements to create at-home medical tests, as well as the market factors that influence consumer adoption in the context of the COVID-19 pandemic. To address testing shortages of COVID-19 tests companies created at-home tests which were rapidly approved by the FDA, bringing at-home testing to the forefront.

History of at-home health testing is reviewed, the medical requirements for creating them, and how the pandemic has affected such testing. Tables are also included to demonstrate currently available tests and potential future tests. The …


Using Infographics To Improve Completion Rates Of The Sepsis Protocol Bundle, Stephen Newbern Jul 2021

Using Infographics To Improve Completion Rates Of The Sepsis Protocol Bundle, Stephen Newbern

Doctor of Nursing Practice Projects

Hospitals have sepsis protocols that must be implemented when a patient shows positive signs and symptoms of a septic infection. Nurses learn about sepsis in nursing school and rarely further their education beyond this basic understanding of the disease. So, when nurses fail to comply with organizational instructions outlined within a defined sepsis protocol bundle, this often leads to a progression of severe sepsis in a patient and, most likely, increased cost for the healthcare facility. Multiple sepsis protocol bundle failures negatively impact organizational ratings established by The Joint Commission for patient care and are highly associated with increased sepsis …


Diffusion-Weighted Mri After Radiofrequency Ablation For Hepatocellular Carcinoma, Heba A. El-Balshy, Mohamed R. El-Kholy, Mohammed S. Al Warraky, Shaimaa A. Hassanien Mar 2021

Diffusion-Weighted Mri After Radiofrequency Ablation For Hepatocellular Carcinoma, Heba A. El-Balshy, Mohamed R. El-Kholy, Mohammed S. Al Warraky, Shaimaa A. Hassanien

Menoufia Medical Journal

Objective This paper aims to evaluate the role of diffusion-weighted (DW) MRI in patients with hepatocellular carcinoma (HCC) treated by radiofrequency ablation (RFA). Background HCC is the most common primary cancer of the liver. RFA has become a widely used treatment for HCC, with some studies reporting significant long-term survival results. DW MRI had been investigated for assessment of treatment response to RFA. Patients and methods From October 2016 to May 2017, 30 patients with 30 lesions diagnosed as HCC had undergone DW MRI after RFA. The results were compared with the abdominal triphasic spiral computed tomography, which was used …


Is First Impression Relevant In Online Health Support Communities? Preliminary Investigation Of The Effects Of Social Presence, Joseph A. Manga, Emmanuel Wusuhon Yanibo Ayaburi, Francis Andoh-Baidoo Jan 2021

Is First Impression Relevant In Online Health Support Communities? Preliminary Investigation Of The Effects Of Social Presence, Joseph A. Manga, Emmanuel Wusuhon Yanibo Ayaburi, Francis Andoh-Baidoo

Information Systems Faculty Publications and Presentations

Patients’ initial impression can influence the kind of reactions they receive and their subsequent participation. Prior studies use inference models to examine participation as a continuum phenomenon. In the online health supporting communities (OHSCs), distinguishing giving participation from receiving participation provide interesting insights at the granular level. Using social presence theory, this study identifies and uses social presence cues in the initial post of 168 patients to predict patients’ giving and receiving participation in a prominent OHSC. Findings reveal that the social presence cues affected the two participation dimensions differently. Specifically, while intimacy is the most important predictor of giving …


Role Of Diffusion-Weighted Imaging As A New Technique In Diagnosis Of Cholangiocarcinoma, Heba S. Ellaban, Mohamed R. Elkholy, Mohamed S. Abdelgawad, Tarek F. Abdellah Sep 2020

Role Of Diffusion-Weighted Imaging As A New Technique In Diagnosis Of Cholangiocarcinoma, Heba S. Ellaban, Mohamed R. Elkholy, Mohamed S. Abdelgawad, Tarek F. Abdellah

Menoufia Medical Journal

Objective To study the role of diffusion-weighted (DW) imaging in the evaluation of cholangiocarcinoma (CC). Background In analyzing the presentation of different types of CC, DW-MRI as a noninvasive, safe technique had great importance. Patients and methods The patients were referred from Hepatobiliary Surgery and Hepatology Departments of the National Liver Institute, Menoufia University, during the period from October 2016 to November 2018. The study included 50 cases, comprising 34 males and 16 females, with age ranging from 34 to 77 years. Patients who were diagnosed with CC by pathology underwent dynamic MRI. Results The study included 50 cases, comprising …


Diffusion Dispersion Imaging: Mapping Oscillating Gradient Spin-Echo Frequency Dependence In The Human Brain., Aidin Arbabi, Jason Kai, Ali R Khan, Corey A Baron Jun 2020

Diffusion Dispersion Imaging: Mapping Oscillating Gradient Spin-Echo Frequency Dependence In The Human Brain., Aidin Arbabi, Jason Kai, Ali R Khan, Corey A Baron

Brain and Mind Institute Researchers' Publications

PURPOSE: Oscillating gradient spin-echo (OGSE) diffusion MRI provides information about the microstructure of biological tissues by means of the frequency dependence of the apparent diffusion coefficient (ADC). ADC dependence on OGSE frequency has been explored in numerous rodent studies, but applications in the human brain have been limited and have suffered from low contrast between different frequencies, long scan times, and a limited exploration of the nature of the ADC dependence on frequency.

THEORY AND METHODS: Multiple frequency OGSE acquisitions were acquired in healthy subjects at 7T to explore the power-law frequency dependence of ADC, the "diffusion dispersion." Furthermore, a …


Characterization And Enhancement Of Local Drug Delivery In Orthopaedic Infection, Tina Khazaee Mar 2020

Characterization And Enhancement Of Local Drug Delivery In Orthopaedic Infection, Tina Khazaee

Electronic Thesis and Dissertation Repository

The delivery of antibiotics is an important component of therapy for orthopedic device-related infections (ODRI). In this study, we have investigated new techniques to characterize and enhance antibiotic delivery for ODRI. Characterization of small-molecule diffusion is essential to the development of drug-delivery systems. We have developed a quantitative, non-invasive, longitudinal, micro-CT technique to quantify the diffusion of small-molecules in an intact phantom. We employed a radio-opaque molecule (i.e., Iohexol) as a surrogate for commonly used antibiotics (e.g., Vancomycin). We characterized diffusion from a finite-core carrier into an agar, tissue-equivalent phantom. The estimate of the diffusion coefficient was derived …


Computer Aided Autism Diagnosis Using Diffusion Tensor Imaging, Yaser A. Elnakieb, Mohamed T. Ali, Ahmed Soliman, Ali H. Mahmoud, Ahmed M. Shalaby, Norah Saleh Alghamdi, Mohammed Ghazal, Ashraf Khalil, Andrew Switala, Robert S. Keynton, Gregory Neal Barnes, Ayman El-Baz Jan 2020

Computer Aided Autism Diagnosis Using Diffusion Tensor Imaging, Yaser A. Elnakieb, Mohamed T. Ali, Ahmed Soliman, Ali H. Mahmoud, Ahmed M. Shalaby, Norah Saleh Alghamdi, Mohammed Ghazal, Ashraf Khalil, Andrew Switala, Robert S. Keynton, Gregory Neal Barnes, Ayman El-Baz

All Works

© 2013 IEEE. Autism Spectrum Disorder (ASD), commonly known as autism, is a lifelong developmental disorder associated with a broad range of symptoms including difficulties in social interaction, communication skills, and restricted and repetitive behaviors. In autism spectrum disorder, numerous studies suggest abnormal development of neural networks that manifest itself as abnormalities of brain shape, functionality, and/ or connectivity. The aim of this work is to present our automated computer aided diagnostic (CAD) system for accurate identification of autism spectrum disorder based on the connectivity of the white matter (WM) tracts. To achieve this goal, two levels of analysis are …


The Diagnostic Value Of Magnetic Resonance Imaging In The Diagnosis Of Nonpalpable Undescended Testis, Adel M. Al Wakeel, Mohamed M. Soliman, Sameh M. Azab Mar 2019

The Diagnostic Value Of Magnetic Resonance Imaging In The Diagnosis Of Nonpalpable Undescended Testis, Adel M. Al Wakeel, Mohamed M. Soliman, Sameh M. Azab

Menoufia Medical Journal

Objective The aim of this study was to assess the value of MRI to localize undescended nonpalpable testis before laparoscopy operation. Background Conventional MRI sequences when combined with diffusion-weighted imaging sequence is a good tool for tissue characterization as they provide functional and structural information about tissues. It could detect the site and viability of nondescended testes. Patients and methods During a period of 12-month duration from January 2016 to December 2016, 20 male patients ranging in age from 5 months to 25 years (mean = 9.86 ± 6.91 years) were included in this study. All patients selected were referred …


Modeling Of Excitatory Amino Acid Transporters And Clearance Of Synaptic Cleft On Millisecond Time Scale, Denis M. Shchepakin, Leonid Kalachev, Michael Kavanaugh Jan 2019

Modeling Of Excitatory Amino Acid Transporters And Clearance Of Synaptic Cleft On Millisecond Time Scale, Denis M. Shchepakin, Leonid Kalachev, Michael Kavanaugh

Biomedical and Pharmaceutical Sciences Faculty Publications

Excitatory Amino Acid Transporters (EAATs) operate over wide time scales in the brain. They maintain low ambient concentrations of the primary excitatory amino acid neurotransmitter glutamate, but they also seem to play a significant role in clearing glutamate from the synaptic cleft in the millisecond time-scale process of chemical communication that occurs between neurons. The detailed kinetic mechanisms underlying glutamate uptake and clearance remain incompletely understood. In this work we used a combination of methods to model EAAT kinetics and gain insight into the impact of transport on glutamate dynamics in a general sense. We derive reliable estimates of the …


Hyperpolarized 3he Mri Ventilatory Apparent Diffusion Coefficient Of Alpha-1 Antitrypsin, Andrew Westcott, Dante P I Capaldi, Alexei Ouriadov, David G Mccormack, Grace Parraga Jan 2019

Hyperpolarized 3he Mri Ventilatory Apparent Diffusion Coefficient Of Alpha-1 Antitrypsin, Andrew Westcott, Dante P I Capaldi, Alexei Ouriadov, David G Mccormack, Grace Parraga

Medical Biophysics Publications

Alpha-1 antitrypsin deficiency (AATD) leads to disabling chronic obstructive pulmonary disease (COPD). Current therapy aimed at slowing lung disease progression includes exogenous alpha-1 antitrypsin augmentation therapy, but there are few potential new treatments under development. Currently used measurements of AATD-related emphysema include the forced expiratory volume in 1 second (FEV1) and the diffusing capacity of carbon monoxide (DLCO); both are relatively insensitive to therapy, although computed tomography (CT) lung density measurements have been shown to worsen more slowly in treated patients.


Diffusion Through The Ex Vivo Vitreal Body – Bovine, Porcine, And Ovine Models Are Poor Surrogates For The Human Vitreous, Sara Shafaie, Victoria Hutter, Marc B. Brown, Michael T. Cook, David Y.S. Chau Oct 2018

Diffusion Through The Ex Vivo Vitreal Body – Bovine, Porcine, And Ovine Models Are Poor Surrogates For The Human Vitreous, Sara Shafaie, Victoria Hutter, Marc B. Brown, Michael T. Cook, David Y.S. Chau

Pharmacology and Animal Models in Research Collection

The human vitreous humour is a complex gel structure whose composition and physical properties can vary considerably from person to person and also change with age. To date, the viscoelastic properties of the human vitreous gel has not been thoroughly investigated and despite many years of intensive research, an ideal vitreous substitute remains a challenge. Understanding the physical structure and properties of the vitreous is of fundamental and therapeutic interest, providing a clear insight into diffusion and transport of administered ophthalmic drug molecules into the vitreous. A number of mammalian surrogates, mainly bovine, porcine and ovine vitreous humours have been …


Application Of A Health Literacy Framework To Explore Patients’ Knowledge Of The Link Between Hpv And Cancer, Alicia L. Best, Rachel Logan, Coralia Vázquez-Otero, Whitney Fung, Vanessa Chee, Erika L. Thompson, Seiichi Villalona, Lora M. A. Thompson, Clement K. Gwede, Ellen M. Daley Jan 2018

Application Of A Health Literacy Framework To Explore Patients’ Knowledge Of The Link Between Hpv And Cancer, Alicia L. Best, Rachel Logan, Coralia Vázquez-Otero, Whitney Fung, Vanessa Chee, Erika L. Thompson, Seiichi Villalona, Lora M. A. Thompson, Clement K. Gwede, Ellen M. Daley

Community and Family Health Faculty Publications

The human papillomavirus (HPV) is a sexually transmitted infection and causes most oropharyngeal (e.g., throat) and anogenital (e.g., anal, cervical) cancers. Research indicates low knowledge about the link between HPV and cancer among the general population, and similar low knowledge of HPV among individuals diagnosed with HPV-associated cancers. This is important because HPV status can have implications for treatment, prognosis, and future sexual decisions. Using a health literacy framework, this study explored how patients diagnosed with HPV-associated cancers accessed, understood, appraised, and applied HPV information. We conducted 27 in-depth interviews with patients seeking care at a comprehensive cancer center; and …


Quantitative Dwi As An Early Imaging Biomarker Of The Response To Chemoradiation In Esophageal Cancer, Benjamin C. Musall Aug 2017

Quantitative Dwi As An Early Imaging Biomarker Of The Response To Chemoradiation In Esophageal Cancer, Benjamin C. Musall

Dissertations & Theses (Open Access)

For patients diagnosed with stages IIa-IIb esophageal cancer, the current standard of care treatment is tri-modality therapy (TMT), where neoadjuvant chemoradiation (nCRT) is followed by surgical resection. Histopathology of resected tumors reveals that pathological complete response (pCR) is achieved in 20-30% of patients through nCRT alone. Because of the high mortality and morbidity associated with esophagectomy, it may be advantageous for patients exhibiting pCR from nCRT alone to be placed under observation rather than completing their TMT. Therefore, a method for predicting response at an early time-point during nCRT is highly desirable. Conventional methods such as endoscopic ultrasound, re-biopsy, and …


Visualizing The Diffusion Of Digital Mammography In New York State, Francis P. Boscoe, Xiuling Zhang Jan 2017

Visualizing The Diffusion Of Digital Mammography In New York State, Francis P. Boscoe, Xiuling Zhang

Epidemiology & Biostatistics Faculty Scholarship

Digital mammography saw rapid adoption during the first decade of the 2000s. According to data maintained by the Food and Drug Administration, which regulates mammography machines, fewer than 1 percent of the machines in 2001 were digital. By 2014, this figure had risen to 94%. We were interested in identifying the times and locations where the technology was introduced within the state of New York as a way of illustrating the uneven introduction of this technology. While the diffusion of medical innovation has been well-studied, there have not been many instances where maps or geographic information science methods have been …


Optical Tracer Size Differences Allow Quantitation Of Active Pumping Rate Versus Stokes–Einstein Diffusion In Lymphatic Transport, Alisha V. Dsouza, Kayla Marra, Jason R. Gunn, Kimberley S. Samkoe, Brian W. Pogue Oct 2016

Optical Tracer Size Differences Allow Quantitation Of Active Pumping Rate Versus Stokes–Einstein Diffusion In Lymphatic Transport, Alisha V. Dsouza, Kayla Marra, Jason R. Gunn, Kimberley S. Samkoe, Brian W. Pogue

Dartmouth Scholarship

Lymphatic uptake of interstitially administered agents occurs by passive convective–diffusive inflow driven by interstitial concentration and pressure, while the downstream lymphatic transport is facilitated by active propulsive contractions of lymphatic vessel walls. Near-infrared fluorescence imaging in mice was used to measure these central components of lymphatic transport for the first time, using two different-sized molecules––methylene blue (MB) and fluorescence-labeled antibody immunoglobulin G (IgG)-IRDye 680RD. This work confirms the hypothesis that lymphatic passive inflow and active propulsion rates can be separated based upon the relative differences in Stokes–Einstein diffusion coefficient. This coefficient specifically affects the passive-diffusive uptake when the interstitial volume …


Multiobjective Guided Priors Improve The Accuracy Of Near-Infrared Spectral Tomography For Breast Imaging, Jinchao Feng, Shudong Jiang, Junqing Xu, Yan Zhao, Brian W. Pogue, Keith D. Paulsen Sep 2016

Multiobjective Guided Priors Improve The Accuracy Of Near-Infrared Spectral Tomography For Breast Imaging, Jinchao Feng, Shudong Jiang, Junqing Xu, Yan Zhao, Brian W. Pogue, Keith D. Paulsen

Dartmouth Scholarship

An image reconstruction regularization approach for magnetic resonance imaging-guided near-infrared spectral tomography has been developed to improve quantification of total hemoglobin (HbT) and water. By combining prior information from dynamic contrast enhanced (DCE) and diffusion weighted (DW) MR images, the absolute bias errors of HbT and water in the tumor were reduced by 22% and 18%, 21% and 6%, and 10% and 11%, compared to that in the no-prior, DCE- or DW-guided reconstructed images in three-dimensional simulations, respectively. In addition, the apparent contrast values of HbT and water were increased in patient image reconstruction from 1.4 and 1.4 (DCE) or …


Perspectives On Transdermal Electroporation, Kevin B. Ita Jan 2016

Perspectives On Transdermal Electroporation, Kevin B. Ita

Faculty Publications & Research of the TUC College of Pharmacy

Transdermal drug delivery offers several advantages, including avoidance of erratic absorption, absence of gastric irritation, painlessness, noninvasiveness, as well as improvement in patient compliance. With this mode of drug administration, there is no pre-systemic metabolism and it is possible to increase drug bioavailability and half-life. However, only a few molecules can be delivered across the skin in therapeutic quantities. This is because of the hindrance provided by the stratum corneum. Several techniques have been developed and used over the last few decades for transdermal drug delivery enhancement. These include sonophoresis, iontophoresis, microneedles, and electroporation. Electroporation, which refers to the temporary …


Derivation Of An Analytical Solution To A Reaction-Diffusion Model For Autocatalytic Degradation And Erosion In Polymer Microspheres, Ashlee N. Ford Versypt, Paul D. Arendt, Daniel W. Pack, Richard D. Braatz Aug 2015

Derivation Of An Analytical Solution To A Reaction-Diffusion Model For Autocatalytic Degradation And Erosion In Polymer Microspheres, Ashlee N. Ford Versypt, Paul D. Arendt, Daniel W. Pack, Richard D. Braatz

Pharmaceutical Sciences Faculty Publications

A mathematical reaction-diffusion model is defined to describe the gradual decomposition of polymer microspheres composed of poly(D,L-lactic-co-glycolic acid) (PLGA) that are used for pharmaceutical drug delivery over extended periods of time. The partial differential equation (PDE) model treats simultaneous first-order generation due to chemical reaction and diffusion of reaction products in spherical geometry to capture the microsphere-size-dependent effects of autocatalysis on PLGA erosion that occurs when the microspheres are exposed to aqueous media such as biological fluids. The model is solved analytically for the concentration of the autocatalytic carboxylic acid end groups of the polymer chains that comprise the microspheres …


The Impact Of State Certification Of Community Health Workers On Team Climate Among Registered Nurses In The United States, Mark Siemon, Geoff Shuster, Blake Boursaw Apr 2015

The Impact Of State Certification Of Community Health Workers On Team Climate Among Registered Nurses In The United States, Mark Siemon, Geoff Shuster, Blake Boursaw

Nursing Faculty Publications and Presentations

A number of states have adopted certification programs for community health workers (CHWs) to improve recognition of CHWs as members of health care teams, increase oversight, and to provide sustainable funding. There has been little research into the impact of state CHW certification on the diffusion and adoption of CHWs into existing health care systems. This study examined the impact of state CHW certification on the perceptions of team climate among registered nurses (RNs) who work with CHWs in states with and without CHW certification programs. The study recruited RNs using a purposeful sampling method and used an online survey, …


The Impact Of State Certification Of Community Health Workers On Team Climate Among Registered Nurses In The United States, Mark Siemon, Geoff Shuster, Blake Boursaw Mar 2015

The Impact Of State Certification Of Community Health Workers On Team Climate Among Registered Nurses In The United States, Mark Siemon, Geoff Shuster, Blake Boursaw

Mark Siemon

A number of states have adopted certification programs for community health workers (CHWs) to improve recognition of CHWs as members of health care teams, increase oversight, and to provide sustainable funding. There has been little research into the impact of state CHW certification on the diffusion and adoption of CHWs into existing health care systems. This study examined the impact of state CHW certification on the perceptions of team climate among registered nurses (RNs) who work with CHWs in states with and without CHW certification programs. The study recruited RNs using a purposeful sampling method and used an online survey, …


Leveraging Practice-Based Research Networks To Accelerate Implementation And Diffusion Of Chronic Kidney Disease Guidelines In Primary Care Practices: A Prospective Cohort Study, James W. Mold, Cheryl B. Aspy, Paul D. Smith, Therese M. Zink, Lyndee Knox, Paula Darby Lipman, Margot Krauss, D. Robert Harris, Chester Fox, Leif I. Solberg, Rachel Cohen Jan 2014

Leveraging Practice-Based Research Networks To Accelerate Implementation And Diffusion Of Chronic Kidney Disease Guidelines In Primary Care Practices: A Prospective Cohort Study, James W. Mold, Cheryl B. Aspy, Paul D. Smith, Therese M. Zink, Lyndee Knox, Paula Darby Lipman, Margot Krauss, D. Robert Harris, Chester Fox, Leif I. Solberg, Rachel Cohen

Family Medicine Faculty Publications

Background

Four practice-based research networks (PBRNs) participated in a study to determine whether networks could increase dissemination, implementation, and diffusion of evidence-based treatment guidelines for chronic kidney disease by leveraging early adopter practices.

Methods

Motivated practices from four PBRNs received baseline and periodic performance feedback, academic detailing, and weekly practice facilitation for 6 months during wave I of the study. Each wave I practice then recruited two additional practices (wave II), which received performance feedback and academic detailing and participated in monthly local learning collaboratives led by the wave I clinicians. They received only monthly practice facilitation. The primary outcomes …


Diffusion Of Social Network Technology And Overuse Among Health Industry Knowledge Workers, Abdel Rahman Toure Jan 2014

Diffusion Of Social Network Technology And Overuse Among Health Industry Knowledge Workers, Abdel Rahman Toure

Walden Dissertations and Doctoral Studies

Many organizations now realize the important role of social network technology (SNT) in building social capital and hence broadening their customer base. However, observations have indicated that, while working, many knowledge workers use SNT to engage in non-job related activities, potentially leading to a decrease in productivity. The purpose of this study was to examine the relationship between the usage of SNT and productivity in the health sector. The theoretical foundation of this study emanated from Rogers's theory of diffusion of innovations and Campbell, Rodney, Scott, and Christopher's theory of performance. Collection of data involved a self-administered survey designed with …