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Low Soluble Drug Encapsulation Based On Architecture Of Layer-By-Layer Assembly For Longer Circulation Time And Targeted Therapy, Pravin Pattekari 2013 Louisiana Tech University

Low Soluble Drug Encapsulation Based On Architecture Of Layer-By-Layer Assembly For Longer Circulation Time And Targeted Therapy, Pravin Pattekari

Doctoral Dissertations

A combined effect of sonication and layer-by-layer assembly (LbL) enhances the solubility of many poorly soluble inorganic and organic materials by forming stable particles with ca. 200 nm size and up to 90 wt% of loading. The entire method is reproducible, easy-to-handle, and flexible for varying surface properties according to the application of the materials. The method develops good colloidal stability of materials in buffers and maintains architecture for future improvement. A top-down approach, with a combined effect of sonication and LbL assembly, ruptures the material and allows adsorption of oppositely charged polyelectrolytes simultaneously. Thus, the approach is applicable for …


The Effect Of Network Transitions On Spontaneous Activity And Sycnhrony In Devloping Neural Networks, Jude P. J. Savarraj 2013 Louisiana Tech University

The Effect Of Network Transitions On Spontaneous Activity And Sycnhrony In Devloping Neural Networks, Jude P. J. Savarraj

Doctoral Dissertations

Connectivity patterns of developing neural circuits and the effects of its dynamics on network behavior, particularly the emergence of spontaneous activity and synchrony, are not clear. We attempt to quantify anatomical connectivity patterns of rat cortical cultures during different stages of development. By culturing the networks on dishes embedded with micro electrode arrays, we simultaneously record electrical activity from multiple regions of the developing network and monitor its electrical behavior, particularly its tendency to fire spontaneously and to synchronize under certain conditions. We investigate possible correlations between changes in the network connectivity patterns and spontaneous electrical activity and synchrony. Cocultures …


Intrinsic Mode Function Synchronization Measures For The Anticipation Of Seizures In Epilpsy, Daniel William Moller 2013 Louisiana Tech University

Intrinsic Mode Function Synchronization Measures For The Anticipation Of Seizures In Epilpsy, Daniel William Moller

Doctoral Dissertations

Epileptic seizures affect as many as 50 million people and often occur without warning or apparent provocation. We explore the applicability of noise-assisted Ensemble Empirical Mode Decomposition (EEMD) for patient-specific seizure anticipation synchronization measures as applied to the EEMD intrinsic mode function (IMF) output. Intracranial EEG data were obtained from pre-surgical monitoring at the Epilepsy Center of the University Hospital of Freiburg. Data from twenty patients were analyzed. For each recorded channel, non-overlapping time windows were submitted to the EEMD algorithm, producing twelve levels of IMFs. IMF synchronization measures (mean and maximum coherence, mean and maximum cross-correlation, correlation coefficient and …


Correlations Between Internal And External Power Outputs During Weightlifting Exercise, Kristof Kipp, Chad Harris, Michelle B. Sabick 2013 Marquette University

Correlations Between Internal And External Power Outputs During Weightlifting Exercise, Kristof Kipp, Chad Harris, Michelle B. Sabick

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Identifying loads that maximize mechanical power is important because training at such loads may optimize gains in dynamic athletic performance. The purpose of this study was to examine correlations between measures of external mechanical power output and internal mechanical joint power output across different loads during a weightlifting exercise. Ten subjects performed 3 sets of the clean exercise at 65, 75, and 85% of 1 repetition maximum (1RM). Peak external mechanical power output was calculated with 4 commonly used methods, whereas an inverse dynamics approach was used to calculate peak internal mechanical power output for the hip, knee, and ankle …


Engineered Production Of Fungal Anticancer Cyclooligomer Depsipeptides In Saccharo-Myces Cerevisiae, Dayu Yu, Fuchao Xu, Jiachen Zi, Siyuan Wang, David Gage, Jia Zeng, Jixun Zhan 2013 Utah State University

Engineered Production Of Fungal Anticancer Cyclooligomer Depsipeptides In Saccharo-Myces Cerevisiae, Dayu Yu, Fuchao Xu, Jiachen Zi, Siyuan Wang, David Gage, Jia Zeng, Jixun Zhan

Biological Engineering Faculty Publications

Two fungal cyclooligomer depsipeptide synthetases (CODSs), BbBEAS (352 kDa) and BbBSLS (348 kDa) from Beauveria bassiana ATCC 7159, were reconstituted in Saccharomyces cerevisiae BJ5464-NpgA, leading to the production of the corresponding anticancer natural products, beauvericins and bassianolide, respectively. The titers of beauvericins (33.82±1.41 mg/l) and bassianolide (21.74±0.08 mg/l) in the engineered S. cerevisiae BJ5464-NpgA strains were comparable to those in the native producer B. bassiana. Feeding D-hydroxyisovaleric acid (D-Hiv) and the corresponding L-amino acid precursors improved the production of beauvericins and bassianolide. However, the high price of D-Hiv limits its application in large-scale production of these cyclooligomer depsipeptides. Alternatively, we …


Surface Fluorescence Studies Of Tissue Mitochondrial Redox State In Isolated Perfused Rat Lungs, Kevin Staniszewski, Said H. Audi, Reyhaneh Sepehr, Elizabeth R. Jacobs, Mahsa Ranji 2013 University of Wisconsin - Milwaukee

Surface Fluorescence Studies Of Tissue Mitochondrial Redox State In Isolated Perfused Rat Lungs, Kevin Staniszewski, Said H. Audi, Reyhaneh Sepehr, Elizabeth R. Jacobs, Mahsa Ranji

Biomedical Engineering Faculty Research and Publications

We designed a fiber-optic-based optoelectronic fluorometer to measure emitted fluorescence from the auto-fluorescent electron carriers NADH and FAD of the mitochondrial electron transport chain (ETC). The ratio of NADH to FAD is called the redox ratio (RR = NADH/FAD) and is an indicator of the oxidoreductive state of tissue. We evaluated the fluorometer by measuring the fluorescence intensities of NADH and FAD at the surface of isolated, perfused rat lungs. Alterations of lung mitochondrial metabolic state were achieved by the addition of rotenone (complex I inhibitor), potassium cyanide (KCN, complex IV inhibitor) and/or pentachlorophenol (PCP, uncoupler) into the perfusate recirculating …


Field Experience As The Centerpiece Of An Integrated Model For Stem Teacher Preparation, Leigh A. Van den Kieboom, Jill McNew-Birren, Ellen Eckman, M. Barbara Silver-Thorn 2013 Marquette University

Field Experience As The Centerpiece Of An Integrated Model For Stem Teacher Preparation, Leigh A. Van Den Kieboom, Jill Mcnew-Birren, Ellen Eckman, M. Barbara Silver-Thorn

Biomedical Engineering Faculty Research and Publications

The purpose of this study was to provide a descriptive account of one pathway for preparing high-quality STEM (science, technology, engineering, and mathematics) teachers for work in high-need urban schools. In this account, we discuss the supports that STEM majors need in learning how to think about the content that they know well, through an educational perspective that focuses on teaching and learning. We also describe the approach that we use that integrates content knowledge, pedagogical content knowledge, and three extensive teaching co-op experiences to facilitate the transition from successful STEM undergraduate students to effective teachers of STEM content. We …


Separation Of Visual And Motor Workspaces During Targeted Reaching Results In Limited Generalization Of Visuomotor Adaptation, Yuming Lei, Michelle J. Johnson, Jinsung Wang 2013 University of Wisconsin - Milwaukee

Separation Of Visual And Motor Workspaces During Targeted Reaching Results In Limited Generalization Of Visuomotor Adaptation, Yuming Lei, Michelle J. Johnson, Jinsung Wang

Biomedical Engineering Faculty Research and Publications

Separating visual and proprioceptive information in terms of workspace locations during reaching movement has been shown to disturb transfer of visuomotor adaptation across the arms. Here, we investigated whether separating visual and motor workspaces would also disturb generalization of visuomotor adaptation across movement conditions within the same arm. Subjects were divided into four experimental groups (plus three control groups). The first two groups adapted to a visual rotation under a “dissociation” condition in which the targets for reaching movement were presented in midline while their arm performed reaching movement laterally. Following that, they were tested in an “association” condition in …


Brief Report: Visuo-Spatial Guidance Of Movement During Gesture Imitation And Mirror Drawing In Children With Autism Spectrum Disorders, Nicole M.G. Salowitz, Petra Eccarius, Audrey Meyer Carson, Kirsten A. Schohl, Sheryl Jayne Stevens, Amy Vaughan van Hecke, Robert A. Scheidt 2013 Marquette University

Brief Report: Visuo-Spatial Guidance Of Movement During Gesture Imitation And Mirror Drawing In Children With Autism Spectrum Disorders, Nicole M.G. Salowitz, Petra Eccarius, Audrey Meyer Carson, Kirsten A. Schohl, Sheryl Jayne Stevens, Amy Vaughan Van Hecke, Robert A. Scheidt

Biomedical Engineering Faculty Research and Publications

Thirteen autistic and 14 typically developing children (controls) imitated hand/arm gestures and performed mirror drawing; both tasks assessed ability to reorganize the relationship between spatial goals and the motor commands needed to acquire them. During imitation, children with autism were less accurate than controls in replicating hand shape, hand orientation, and number of constituent limb movements. During shape tracing, children with autism performed accurately with direct visual feedback, but when viewing their hand in a mirror, some children with autism generated fewer errors than controls whereas others performed much worse. Large mirror drawing errors correlated with hand orientation and hand …


Wavelength Optimization For Quantitative Spectral Imaging Of Breast Tumor Margins, Justin Y. Lo, J. Quincy Brown, Sulochana Dhar, Bing Yu, Gregory M. Palmer, Nan M. Jokerst, Nirmala Ramanujam 2013 Duke University

Wavelength Optimization For Quantitative Spectral Imaging Of Breast Tumor Margins, Justin Y. Lo, J. Quincy Brown, Sulochana Dhar, Bing Yu, Gregory M. Palmer, Nan M. Jokerst, Nirmala Ramanujam

Biomedical Engineering Faculty Research and Publications

A wavelength selection method that combines an inverse Monte Carlo model of reflectance and a genetic algorithm for global optimization was developed for the application of spectral imaging of breast tumor margins. The selection of wavelengths impacts system design in cost, size, and accuracy of tissue quantitation. The minimum number of wavelengths required for the accurate quantitation of tissue optical properties is 8, with diminishing gains for additional wavelengths. The resulting wavelength choices for the specific probe geometry used for the breast tumor margin spectral imaging application were tested in an independent pathology-confirmed ex vivo breast tissue data set and …


An Investigation And Analysis Of The Vestibulo-Ocular Reflex In A Vibration Environment, Daniel J. Uribe 2013 Air Force Institute of Technology

An Investigation And Analysis Of The Vestibulo-Ocular Reflex In A Vibration Environment, Daniel J. Uribe

Theses and Dissertations

Forty years of innovations have greatly improved Helmet-Mounted Displays (HMDs) and their integration into military systems. However, a significant issue with HMDs is the effect of vibration and the associated Vestibulo-Ocular Reflex (VOR). When a human’s head is subject to low-frequency vibration, the VOR stabilizes the eye with respect to objects in the external environment. However, this response is inappropriate in HMDs as the display moves with the user’s head and the VOR blurs the image as it is projected on the human retina. Current compensation techniques suggest increasing the size of displayed graphics or text to compensate for the …


Computer Based Behavioral Biometric Authentication Via Multi-Modal Fusion, Kyle O. Bailey 2013 Air Force Institute of Technology

Computer Based Behavioral Biometric Authentication Via Multi-Modal Fusion, Kyle O. Bailey

Theses and Dissertations

Biometric computer authentication has an advantage over password and access card authentication in that it is based on something you are, which is not easily copied or stolen. One way of performing biometric computer authentication is to use behavioral tendencies associated with how a user interacts with the computer. However, behavioral biometric authentication accuracy rates are much larger then more traditional authentication methods. This thesis presents a behavioral biometric system that fuses user data from keyboard, mouse, and Graphical User Interface (GUI) interactions. Combining the modalities results in a more accurate authentication decision based on a broader view of the …


Adaptive Human Control Gains During Precision Grip, Erik D. Engeberg 2013 University of Akron Main Campus

Adaptive Human Control Gains During Precision Grip, Erik D. Engeberg

Mechanical Engineering Faculty Research

Eight human test subjects attempted to track a desired position trajectory with an instrumented manipulandum (MN). The test subjects used the MN with three different levels of stiffness. A transfer function was developed to represent the human application of a precision grip from the data when the test subjects initially displaced the MN so as to learn the position mapping from the MN onto the display. Another transfer function was formed from the data of the remainder of the experiments, after significant displacement of the MN occurred. Both of these transfer functions accurately modelled the system dynamics for a portion …


Nanosecond Pulsed Electric Field Thresholds For Nanopore Formation In Neural Cells., Caleb C Roth, Gleb P Tolstykh, Jason A Payne, Marjorie A Kuipers, Gary L. Thompson III, Mauris N DeSilva, Bennett L Ibey 2013 Rowan University

Nanosecond Pulsed Electric Field Thresholds For Nanopore Formation In Neural Cells., Caleb C Roth, Gleb P Tolstykh, Jason A Payne, Marjorie A Kuipers, Gary L. Thompson Iii, Mauris N Desilva, Bennett L Ibey

Henry M. Rowan College of Engineering Departmental Research

The persistent influx of ions through nanopores created upon cellular exposure to nanosecond pulse electric fields (nsPEF) could be used to modulate neuronal function. One ion, calcium (Ca(2+)), is important to action potential firing and regulates many ion channels. However, uncontrolled hyper-excitability of neurons leads to Ca(2+) overload and neurodegeneration. Thus, to prevent unintended consequences of nsPEF-induced neural stimulation, knowledge of optimum exposure parameters is required. We determined the relationship between nsPEF exposure parameters (pulse width and amplitude) and nanopore formation in two cell types: rodent neuroblastoma (NG108) and mouse primary hippocampal neurons (PHN). We identified thresholds for nanoporation using …


Bacterial Growth On Metal And Non-Metal Surfaces In A Static Bioreactor, Rolan Yuk Loong Liong 2013 California Polytechnic State University, San Luis Obispo

Bacterial Growth On Metal And Non-Metal Surfaces In A Static Bioreactor, Rolan Yuk Loong Liong

Master's Theses

Research was conducted to observe bacterial growth on the surface of metals in a static bioreactor. Metal and non-metal samples were subjected to bacterial exposure (1 day and 9 days). The metal samples were surface treated prior to bacterial exposure. The microstructures of the surface treated samples were analyzed by optical microscopy. After exposure, the microstructures of the samples were analyzed by scanning electron microscopy (SEM). The analysis suggested that microbial attachment on the surface was related to the underlying microstructure of steel. The preferential attachment of microbes could potentially be influenced by cathodic and anodic regions created by the …


Novel Approach To Junctional Bleeding: Tourniquet Device Proposal For Battlefield Hemorrhage Control, Kyle W. Cabaniss 2013 California Polytechnic State University, San Luis Obispo

Novel Approach To Junctional Bleeding: Tourniquet Device Proposal For Battlefield Hemorrhage Control, Kyle W. Cabaniss

Master's Theses

This study investigated possible solutions to the current wartime problem of junctional hemorrhaging, or massive traumatic hemorrhaging in non-tourinquetable areas such as the neck, groin, or armpit. Junctional hemorrhaging has been identified as a major contributor to potentially survivable deaths seen on the battlefield today and therefore is a priority for the U.S. armed and coalition forces (Kragh et al., 2011a; Bozeman, 2011). Common tourniquets today are standard issue and carried by soldiers in the military, but are limited to distal extremity trauma. As the battlefield has changes however, trauma has transformed from commonly seen gunshot wounds to more extreme …


Effects Of Ovariectomy And Anatomical Location On Osteonal Encroachment In Adult Cortical Ovine Bone, Paige Brell Ryan 2013 California Polytechnic State University, San Luis Obispo

Effects Of Ovariectomy And Anatomical Location On Osteonal Encroachment In Adult Cortical Ovine Bone, Paige Brell Ryan

Master's Theses

The purpose of this study is to further quantify adult ovine ovariectomized bone for new remodeling characteristics to obtain a better understanding of how remodeling is occurring and the effectiveness of this animal model for the study of postmenopausal osteoporosis. Postmenopausal osteoporosis is a major health concern and animal models to test new treatment options are needed. The ovine model is a good option because the ewes undergo Haversian remodeling, are a large sized animal, and have a similar hormone profile to humans. Ewes, however, do not undergo a natural menopause, so an ovariectomy surgery was conducted in the sheep …


A Microfluidic Pretreatment Isoelectric Focusing Dc-Field Assisted H-Filter For The Separation Of Charged Particles, Cameron Sean Carroll 2013 California Polytechnic State University, San Luis Obispo

A Microfluidic Pretreatment Isoelectric Focusing Dc-Field Assisted H-Filter For The Separation Of Charged Particles, Cameron Sean Carroll

Biomedical Engineering

Microfluidic devices are small portable diagnostic chips that allow for analysis of a biologic sample at relatively low cost. This makes them ideal for settings where a hospital is unavailable. The microfluidic pretreatment isoelectric focusing DC-field assisted H-filter is a device that allows for the separation of differently charged particles in a biologic sample. It does this by employing the concepts of diffusion, electrophoresis, and isoelectric focusing. This is perfect for isolation of a desired analyte or separation of waste from a sample in order to achieve better diagnostic results. The device was first modeled mathematically and visually using Comsol. …


Investigating The Reproducibility Of The Current Bvm Protocol, Corey Gross 2013 California Polytechnic State University, San Luis Obispo

Investigating The Reproducibility Of The Current Bvm Protocol, Corey Gross

Biomedical Engineering

Coronary Artery Disease (CAD) is responsible for 1 death every minute in the US. Angioplasty with the implantation of stents is a common treatment method for CAD. Although there is a variety of stents currently on the market, there is still a need to develop new types for different pathologic conditions. Preliminary assessment of the physiological response to new stents is needed as they are being developed. The FDA approval process implemented today is a long, tedious path with a range of testing methods that include static in vitro testing and high-cost animal testing. Tissue engineered blood vessels have been …


Tracking Knee Joint Functional Axes Through Tikhonov Filtering And Plűcker Coordinates, Wangdo Kim, Yoon-Hyuk Kim, António P. Veloso, Sean S. Kohles 2013 Universidade Técnica de Lisboa

Tracking Knee Joint Functional Axes Through Tikhonov Filtering And Plűcker Coordinates, Wangdo Kim, Yoon-Hyuk Kim, António P. Veloso, Sean S. Kohles

Mechanical and Materials Engineering Faculty Publications and Presentations

Researchers have reported several compensation methods to estimate bone and joint position from a cluster of skin-mounted markers as influenced by Soft Tissue Artifacts (STA). Tikhonov Regularization Filtering (TRF) as a means to estimate Instantaneous Screw Axes (ISA) was introduced here as a means to reduce the displacement of a rigid body to its simplest geometric form. Recent studies have suggested that the ISA of the knee, i.e., Knee Functional Axes (KFA), might be closely connected to the estimation of constraint forces such as those due to medial and lateral connective tissues. The estimations of ISAs were known to be …


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