Benjamin Wheeler is developing a wearable biosensor to identify mild traumatic brain injury (mTBI) following head trauma. The sensor uses lipid vesicles containing fluorescent dye that is quenched until a mechanical impact disrupts the vesicles, causing the dye to fluoresce. Preliminary tests show vesicle leakage in response to an electromagnetic shaker. The project aims to 1) characterize the relationship between vesicle leakage and applied force, and 2) create an optimized vesicle-hydrogel sensor for incorporation into protective headwear to allow for on-site mTBI diagnosis.
How To Study Structural and Functional Properties of TendonInsideScientific
WATCH THE VIDEO: http://bit.ly/2nl7Nx6
In this webinar presented by Aurora Scientific, Matthew Borkowski and Dylan Sarver discuss how to characterize the structural and functional properties of tendon.
Specifically, Mr. Borkowski describes the engineering behind the multi-purpose Aurora Scientific Dual Mode Lever — a fast actuator and sensitive force transducer in one — and how this device can be used to study connective tissue.
Following, Mr. Sarver discusses his current research focused on sex-related differences in the structural and functional status of Tendon, from macromolecular structural properties to transcriptomic, proteomic, and cell biology of resident tendon fibroblasts. He explains why tendon research is important, reviews methodology for investigating tendon structure and function, and discusses research findings supporting sex-related differences in tendon.
Key topics covered during this webinar will include…
- How to use The Dual-Mode Lever to perfom demanding stress/strain assays
- What is a tendon, and why is tendon research important
- How to characterize the structural and functional status of tendon
- Case Study: investigating sex-related differences in tendon
Studying Retinal Function in Large Animals: Laser-Induced Choroidal Neovascul...InsideScientific
The document describes a laser-induced choroidal neovascularization model in pigs for studying retinal diseases. It discusses the Micron X imaging system for obtaining high-quality images of the retina and fluorescein angiograms in large animals like pigs. The model involves using laser shots to induce CNV lesions and then treating them with drugs like aflibercept to evaluate effectiveness. Quantitative analysis of the lesions is done using OCT, fluorescein angiography, and flat mounts, showing that aflibercept significantly reduces CNV development. The pig model is said to be more clinically relevant and translatable than rodent models for testing new therapies.
Employing Electrophysiology and Optogenetics to Measure and Manipulate Neuron...InsideScientific
In this webinar, Dr. Tahl Holtzman, Founder of Cambridge NeuroTech, describes a new generation of silicon neural probes offering dozens of recording channels in precisely spaced, high-resolution arrays, built using sophisticated fabrication techniques borrowed from the electronics industry, along with simple-to-follow surgical implantation schemes for both acute and chronic animals.
Watch to learn how to take advantage of ultra-small chronic drives to open up scalability to span multiple brain areas in parallel and to achieve excellent chronic stability. In addition, Dr. Holtzman demonstrates integration of novel probes and drives offered by Cambridge NeuroTech with optogenetics that thereby enable your experiments to have the combined capability for measurement AND manipulation of neuronal activity in both acute and freely behaving settings.
This webinar will benefit both established electrophysiologists who wish to increase their data yield and experimental reach as well as those investigators whose expertise is centred in and around the animal behavioural, neuropharmacological, and optogenetics arenas. Viewers will learn what silicon neural probes are and how to use them in both acute and chronic experiments, best-practice techniques for surgical implantation in species ranging from mice to monkeys and how to integrate fibre optic cannulas with your probes to enable simultaneous opto-electrophysiology.
Neural mechanics and its contribution to nerve cell repairSpyros Ktenas
The document discusses neural mechanics and its contribution to nerve cell repair. It describes different types of nerve damage including neurapraxia, axonotmesis, and neurotmesis. Diseases that cause nervous system damage are also outlined such as epilepsy, Parkinson's, and Alzheimer's. The document then explores current techniques for nerve repair including tissue engineering and rehabilitation technologies like robotic systems and virtual reality. Devices for detecting nerve function like optical tweezers and atomic force microscopy are also summarized. In conclusion, neural mechanics contributes to nerve repair but further development is still needed in areas like alternative grafts and non-invasive damage assessment.
This document summarizes research into using porous templated scaffolds (PTS) to modulate neuroinflammation in the central nervous system (CNS). Excessive neuroinflammation inhibits healing after spinal cord injury (SCI) and reduces the performance of brain implants like electrodes over time. The researchers found that PTS can modulate the phenotype of inflammatory cells. They plan to test softer PTS implants within the spinal cord after transection and in the cortex to reduce encapsulation of electrodes and associated declines in performance over time. Histology and functional recovery tests will assess macrophage polarization and implant integration.
Overcoming nerve gaps can be done through early repair, mobilization, transposition, bone shortening, or nerve grafts and conduits. For nerve transections, autografts are the gold standard but conduits and allografts are alternatives that avoid donor site morbidity. Evidence shows synthetic conduits have mixed results for major nerves but good outcomes for short digital nerve gaps, while vein and nerve allografts can achieve equivalent results to autografts for gaps under 3cm. Nerve wraps following repair protect the site from adhesion.
Retinal prostheses are implantable devices designed to restore vision in patients with retinal diseases that have destroyed photoreceptors. The document describes three types of retinal prostheses - epiretinal, subretinal, and suprachoroidal - based on their implantation site. It provides details on the design, surgical procedure, and clinical outcomes of some specific retinal prosthesis devices, including the Bionic Vision Australia suprachoroidal implant and the Retina Implant Alpha-IMS subretinal implant. Complications of retinal prostheses are also discussed.
CUSTOM IMPLANTS
Research, Regenerative Medicine and Personalized Surgery at Rizzoli Orthopedic Institute
PERSONALIZED SCAFFOLDS: In-vitro validation of magnetic microstructured 3D printed scaffolds
In-vitro validation of microstructured scaffolds through 3D printing in bioabsorbable materials colonized with human cells. A magnetic manipulator of cells, magnetized by internalization or by coating of magnetic nanoparticles, is developing its prototype
How To Study Structural and Functional Properties of TendonInsideScientific
WATCH THE VIDEO: http://bit.ly/2nl7Nx6
In this webinar presented by Aurora Scientific, Matthew Borkowski and Dylan Sarver discuss how to characterize the structural and functional properties of tendon.
Specifically, Mr. Borkowski describes the engineering behind the multi-purpose Aurora Scientific Dual Mode Lever — a fast actuator and sensitive force transducer in one — and how this device can be used to study connective tissue.
Following, Mr. Sarver discusses his current research focused on sex-related differences in the structural and functional status of Tendon, from macromolecular structural properties to transcriptomic, proteomic, and cell biology of resident tendon fibroblasts. He explains why tendon research is important, reviews methodology for investigating tendon structure and function, and discusses research findings supporting sex-related differences in tendon.
Key topics covered during this webinar will include…
- How to use The Dual-Mode Lever to perfom demanding stress/strain assays
- What is a tendon, and why is tendon research important
- How to characterize the structural and functional status of tendon
- Case Study: investigating sex-related differences in tendon
Studying Retinal Function in Large Animals: Laser-Induced Choroidal Neovascul...InsideScientific
The document describes a laser-induced choroidal neovascularization model in pigs for studying retinal diseases. It discusses the Micron X imaging system for obtaining high-quality images of the retina and fluorescein angiograms in large animals like pigs. The model involves using laser shots to induce CNV lesions and then treating them with drugs like aflibercept to evaluate effectiveness. Quantitative analysis of the lesions is done using OCT, fluorescein angiography, and flat mounts, showing that aflibercept significantly reduces CNV development. The pig model is said to be more clinically relevant and translatable than rodent models for testing new therapies.
Employing Electrophysiology and Optogenetics to Measure and Manipulate Neuron...InsideScientific
In this webinar, Dr. Tahl Holtzman, Founder of Cambridge NeuroTech, describes a new generation of silicon neural probes offering dozens of recording channels in precisely spaced, high-resolution arrays, built using sophisticated fabrication techniques borrowed from the electronics industry, along with simple-to-follow surgical implantation schemes for both acute and chronic animals.
Watch to learn how to take advantage of ultra-small chronic drives to open up scalability to span multiple brain areas in parallel and to achieve excellent chronic stability. In addition, Dr. Holtzman demonstrates integration of novel probes and drives offered by Cambridge NeuroTech with optogenetics that thereby enable your experiments to have the combined capability for measurement AND manipulation of neuronal activity in both acute and freely behaving settings.
This webinar will benefit both established electrophysiologists who wish to increase their data yield and experimental reach as well as those investigators whose expertise is centred in and around the animal behavioural, neuropharmacological, and optogenetics arenas. Viewers will learn what silicon neural probes are and how to use them in both acute and chronic experiments, best-practice techniques for surgical implantation in species ranging from mice to monkeys and how to integrate fibre optic cannulas with your probes to enable simultaneous opto-electrophysiology.
Neural mechanics and its contribution to nerve cell repairSpyros Ktenas
The document discusses neural mechanics and its contribution to nerve cell repair. It describes different types of nerve damage including neurapraxia, axonotmesis, and neurotmesis. Diseases that cause nervous system damage are also outlined such as epilepsy, Parkinson's, and Alzheimer's. The document then explores current techniques for nerve repair including tissue engineering and rehabilitation technologies like robotic systems and virtual reality. Devices for detecting nerve function like optical tweezers and atomic force microscopy are also summarized. In conclusion, neural mechanics contributes to nerve repair but further development is still needed in areas like alternative grafts and non-invasive damage assessment.
This document summarizes research into using porous templated scaffolds (PTS) to modulate neuroinflammation in the central nervous system (CNS). Excessive neuroinflammation inhibits healing after spinal cord injury (SCI) and reduces the performance of brain implants like electrodes over time. The researchers found that PTS can modulate the phenotype of inflammatory cells. They plan to test softer PTS implants within the spinal cord after transection and in the cortex to reduce encapsulation of electrodes and associated declines in performance over time. Histology and functional recovery tests will assess macrophage polarization and implant integration.
Overcoming nerve gaps can be done through early repair, mobilization, transposition, bone shortening, or nerve grafts and conduits. For nerve transections, autografts are the gold standard but conduits and allografts are alternatives that avoid donor site morbidity. Evidence shows synthetic conduits have mixed results for major nerves but good outcomes for short digital nerve gaps, while vein and nerve allografts can achieve equivalent results to autografts for gaps under 3cm. Nerve wraps following repair protect the site from adhesion.
Retinal prostheses are implantable devices designed to restore vision in patients with retinal diseases that have destroyed photoreceptors. The document describes three types of retinal prostheses - epiretinal, subretinal, and suprachoroidal - based on their implantation site. It provides details on the design, surgical procedure, and clinical outcomes of some specific retinal prosthesis devices, including the Bionic Vision Australia suprachoroidal implant and the Retina Implant Alpha-IMS subretinal implant. Complications of retinal prostheses are also discussed.
CUSTOM IMPLANTS
Research, Regenerative Medicine and Personalized Surgery at Rizzoli Orthopedic Institute
PERSONALIZED SCAFFOLDS: In-vitro validation of magnetic microstructured 3D printed scaffolds
In-vitro validation of microstructured scaffolds through 3D printing in bioabsorbable materials colonized with human cells. A magnetic manipulator of cells, magnetized by internalization or by coating of magnetic nanoparticles, is developing its prototype
Single-Cell Electrophysiology and 2-Photon Imaging in Awake Mice with 2D-Loco...InsideScientific
In this webinar sponsored by Neurotar, experts present their research utilizing the Mobile HomeCage®, an experimental tool which ensures the stability required for high-precision neurophysiological techniques while allowing mice to navigate and explore their environment.
Case Study #1:
Dr. Sarah Stuart and Dr. Jon Palacios-Filardo of the University of Bristol present their studies combining analysis of goal-directed behavior with whole-cell recordings from the hippocampus of awake mice. The researchers share useful tips for the surgery protocol and for adjusting the head fixation angle in order to facilitate mouse motility and exploratory behavior.
Case Study #2:
Dr. Alexander Dityatev and Weilun Sun from the German Center for Neurodegenerative Diseases (DZNE) discuss 2-photon imaging of fluorescently labeled microglia in vivo in the context of neurodegenerative disease. They also present their recent data on the effects of different anesthetics on the microglial response to localized laser injury.
Case Study #3:
Dr. Norbert Hájos from the Hungarian Academy of Sciences presents his lab’s research into the amygdala’s role in reward-driven behavior. He shares the challenges of making single-unit recordings using silicon probes during mouse locomotion and subsequent morphological identification of active neurons in the amygdala.
Key topics covered during this webinar include:
- Requirements for stable single-cell recordings and 2-photon imaging in behaving mice
- Challenges of combining high-precision techniques with behavioral research
- Methodological considerations for improving exploratory behavior in head-fixed mice
- Quantitative analysis of microglial function using 2-photon microscopy in awake mice
- Recording neuronal activity in the amygdala of awake mice followed by morphological identification of recorded neurons
This design document proposes renovating the Avery Breathing Pacemaker electrode for use as a nerve cuff electrode to restore bladder function in individuals with spinal cord injuries. The current electrode design has limitations that could be addressed. The proposed redesigned nerve cuff would incorporate a shape memory alloy to allow self-closing around the nerve during implantation. It would also modify the lead wires to have a coiled design for flexibility and strain relief. The goal is to develop an improved nerve cuff electrode that can safely and effectively restore bladder control through electrical stimulation of peripheral nerves.
Cytotherapy for osteonecrosis of hip.acta medica internationalSanjeev kumar Jain
The document discusses the use of cytotherapy, specifically autologous bone marrow transplantation, for the treatment of osteonecrosis of the hip. It provides background on how osteonecrosis leads to a decrease in mesenchymal stem cells and impaired bone remodeling. The document then reviews studies that have found autologous bone marrow transplantation can help increase stem cell levels and promote bone repair, potentially preventing the need for hip replacement surgery.
Monitoring live cell viability Comparative studyWerden Keeler
This document compares three live cell imaging techniques: fluorescence microscopy, oblique incidence reflection microscopy, and phase contrast microscopy. It finds that oblique incidence reflection microscopy is the simplest, least expensive, and least phototoxic method, causing the least damage to live cells during long-term monitoring of cell viability. The document describes the equipment and cell lines used, including normal and cancerous cell lines tagged with fluorescent proteins or unlabeled, to evaluate the stresses induced by different illumination techniques.
Two novel flexible neural microelectrode arrays (MEAs) were designed and fabricated - Chelsea, a penetrating array for intracortical recording and stimulation, and Sabrina, a combined surface and penetrating array for micro-ECoG and intracortical recording. Glass carbon (GC) was used due to its biocompatibility, electrochemical properties, and ability to be photo-patterned. Testing showed GC has higher charge storage capacity, lower impedance, and a wider electrochemical window than platinum. It also exhibited greater corrosion resistance after aging and stimulation cycling. The flexible GC MEAs enable new MEA designs and more reliable, chronic neural signal acquisition.
Cerebral Open Flow Microperfusion (cOFM) for in vivo Cerebral Fluid Sampling ...InsideScientific
Cerebral open flow microperfusion (cOFM) is a minimally invasive, in vivo sampling technology that allows continuous long-term sampling of cerebral fluid in living animals. The decisive advantage of cOFM is that the cOFM probe is membrane–free and comprises macroscopic openings which offer the possibility for a multitude of applications without restriction regarding size, lipophilicity or protein binding effects of the collected substances. The cOFM probe is designed to elicit minimal tissue reactions and allows for reconstitution of the blood-brain barrier (BBB). Thus, cOFM can sample cerebral fluids in living and freely moving animals with intact BBB.
During this webinar, Dr. Joanna Hummer introduces cOFM and presents how cOFM is used as an in vivo sampling technology in neuroscience for drug development.
Dr. Florie Le Prieult, presents data her team collected using cOFM during a pharmacokinetic studies of therapeutic antibodies. Her study includes head-to-head comparison of cOFM and microdialysis.
Bone and Cartilage regeneration with cells and tissue engineering products - ...Enric Caceres
Bone and Cartilage regeneration with cells and tissue engineering products - Dr. Enric Cáceres - B-Debate 17/02/2015 http://www.bdebate.org/en/forum/advanced-therapies-and-regenerative-medicine-promise-21st-century
High Throughput Investigation of EC Coupling in Isolated Cardiac MyocytesInsideScientific
During this webinar sponsored by IonOptix, Michiel Helmes, PhD discusses recent advancements in instrumentation that address the shortfalls of low throughput EC coupling characterization. Specifically, Dr. Helmes explains the technology behind faster data acquisition and analysis, as well as improvements to the studies that offer more data acquisition fidelity, and automated data collection. He offers insights into best-practices for proper EC coupling measurement and highlight improvements to data handling, namely faster, automated data analysis.
Background: Measuring and analyzing calcium and contractility in isolated cardiomyocytes offers important insights into cardiac function. However, traditional methods of obtaining EC coupling data are somewhat limited to lower throughput — for many applications, particularly drug discovery research, this presents a big challenge. Additionally, low throughput data acquisition and analysis may lack the statistical power necessary to fully resolve differences, or changes, in cardiac function. Isolated myocytes can behave heterogeneously, thus greater sample numbers are essential for accurate and reliable modeling of cardiac behavior.
This document discusses bioprinting vessel-like constructs using hyaluronan hydrogels crosslinked with tetrahedral polyethylene glycol tetracrylates. Rheology testing found the crosslinked hydrogels were stiffer than PEGDA crosslinked hydrogels. Cell viability studies showed increased proliferation over 7 days for cells encapsulated in the hydrogels. The bioprinted constructs maintained cell viability for up to 4 weeks in culture. This technique provides an alternative for engineering vascularized tissue constructs.
This document discusses the use of gold nanorods (GNRs) in laser tissue welding (LTW). GNRs exhibit surface plasmon resonance that can be tuned to match laser wavelengths. This allows GNRs to efficiently absorb laser energy and heat surrounding tissue for welding. Studies demonstrated LTW of cartilage, cornea, intestine, and lens capsules using GNRs and near-infrared lasers. GNRs were incorporated into solders, patches, or hydrogels applied to tissue before laser irradiation, enabling sutureless tissue fusion and repair. LTW with GNRs showed potential for accelerated healing with minimal foreign body reactions or leaks compared to conventional suturing.
The document discusses regression following LASIK surgery. It summarizes a study examining the effects of epithelial and biomechanical changes on refractive outcomes after LASIK. The study found that these changes accounted for inaccuracies in LASIK treatment. It also determined that diagnosing regression requires analysis of layered corneal changes after LASIK using techniques like ultrasound, and that directly measuring flap and stromal thickness is important for safety when considering enhancement procedures.
Rachael Pearson is a Royal Society University Research Fellow whose research focuses on developing stem cell therapy for retinal repair and regeneration. She has established proof-of-concept for restoring vision through rod photoreceptor transplantation. Her current areas of interest include defining strategies to restore cone-mediated vision, understanding photoreceptor precursor migration in development and transplantation, and determining how to break down barriers in the degenerating retina to improve transplantation outcomes. Her lab utilizes techniques such as microscopy, stem cell culture, molecular biology, and behavioral testing to advance photoreceptor replacement therapies for treating blindness.
Efficiency of Stem Cell After Spinal Cord Injury with Clip-Compression_ Crims...Crimsonpublisherssmoaj
Efficiency of Stem Cell After Spinal Cord Injury with Clip-Compression by Tae Hoon Lee* in Crimson Publishers: Surgery Journal Impact Factor
Our experiment grafted mouse embryonic stem cell (mESC) to influence behavioral deficiency in rodent animal models of clip compressive surgery inducing spinal cord injury (SCI) of central nervous system. Our research proved the effect of grafted stem cells to the injured spinal cord region, focusing the application of mouse embryonic stem cells for regeneration of spinal cord nervous injury. Therefore, our research suggests manifest results that implantation of mouse embryonic stem cell could show behavioral improvement after severe spinal cord damage.
https://crimsonpublishers.com/smoaj/fulltext/SMOAJ.000533.php
For more open access journals in Crimson Publishers
Please click on: https://crimsonpublishers.com/
For more articles on Surgery Journal Impact Factor
Please click on link: https://crimsonpublishers.com/smoaj/index.php
Please follow the below link for our LinkedIn page
https://www.linkedin.com/company/crimsonpublishers
This document discusses lensfree microscopy and tomography techniques developed by Serhan Isikman for biomedical applications. [1] Lensfree microscopy uses holograms recorded by a sensor array to digitally reconstruct microscope images over a wide field of view in a compact, low-cost system. [2] It has been used to rapidly count red blood cells on a chip with high accuracy. [3] Lensfree optical tomography similarly uses holograms from multiple angles to computationally generate 3D images without lenses, achieving micrometer-scale resolution.
Experimental Studies of the Structure and Dynamics of Actin Networks
The document discusses experimental methods used to study actin networks, including optical trapping and particle tracking. Optical tweezers were used to generate 200 independent optical traps to manipulate particles. Particle tracking software was then used to analyze particle motion. Results showed that actin samples polymerized at 15°C and that networks healed radially inward after damage at a specific rate, with further experiments planned to study different healing based on damage type.
This project aims to develop stable electrical contact between cortical organoids and embedded flexible electrodes. A 3D-printed tube insert was designed to promote intimate contact between organoids and electrodes by providing an inclined space for organoids to naturally attach to electrode surfaces. Impedance measurements were taken of electrode contacts to identify functional recording sites. Initial experiments culturing organoids on electrodes used elevated dishes or inclined PDMS pieces to stabilize the organoid-electrode setup. Future steps involve demonstrating long-term organoid survival when embedded with electrodes and recording electrical activity from organoid neurons over time.
Adult Stem cells in Orthopaedics present and future perspectives.
Παρουσίαση του Δρ. Σταύρου Αλευρογιάννη που έγινε στο ξενοδοχείο Χίλτον, στις 12/06/15 στα πλαίσια Ημερίδας της Ελληνικής Εταιρείας Αναγεννητικής Ιατρικής, Αντιγήρανσης και Βιοτεχνολογίας, στο 41ο Πανελλήνιο Ιατρικό Συνέδριο.
"H θέση της αναγεννητική Ιατρικής στις παθήσεις Οστών και Αρθρώσεων"
La hepatitis A es una inflamación del hígado causada por el virus de la hepatitis A. Se transmite principalmente a través del agua o los alimentos contaminados. Los síntomas incluyen fiebre, malestar, pérdida del apetito, dolor abdominal y color amarillento de la piel y los ojos. La mayoría de las personas se recuperan por completo de la hepatitis A.
This document contains solutions to 20 math questions covering topics like sets, sequences, statistics, properties of numbers, and reasoning. It also provides a link to additional resources. The questions involve calculating quantities from sets and surveys, identifying patterns in sequences, determining reasoning types, and evaluating true/false statements.
Suzanne Collins nació en 1962 en Connecticut. Estudió drama en la Universidad de Indiana y más tarde amplió sus estudios en Nueva York. En 1991 comenzó a escribir literatura para niños y jóvenes, inspirándose en Alicia en el País de las Maravillas. Se hizo famosa por sus exitosas series de Los Juegos del Hambre, en Llamas y Sinsajo, que crearon un gran fenómeno fan entre el público joven.
Timea Grego ECON 662 Grad Research Paper FinalTimea Grego
This document is a graduate research paper that examines China's foreign direct investment policy and whether it has contributed to China becoming a pollution haven. The paper begins by introducing the topic and outlines its aims to explore the impact of China's FDI policy on the global environment. It then discusses the pollution haven hypothesis and provides examples of studies that have analyzed the relationship between FDI, environmental degradation and China. However, the paper notes that most studies have focused on lax environmental regulations rather than cheap energy resources. The rest of the paper will analyze China's economic reforms and links to trade and FDI, examine whether China is a pollution haven by looking at affected industries and the role of FDI, and consider policy recommendations.
Single-Cell Electrophysiology and 2-Photon Imaging in Awake Mice with 2D-Loco...InsideScientific
In this webinar sponsored by Neurotar, experts present their research utilizing the Mobile HomeCage®, an experimental tool which ensures the stability required for high-precision neurophysiological techniques while allowing mice to navigate and explore their environment.
Case Study #1:
Dr. Sarah Stuart and Dr. Jon Palacios-Filardo of the University of Bristol present their studies combining analysis of goal-directed behavior with whole-cell recordings from the hippocampus of awake mice. The researchers share useful tips for the surgery protocol and for adjusting the head fixation angle in order to facilitate mouse motility and exploratory behavior.
Case Study #2:
Dr. Alexander Dityatev and Weilun Sun from the German Center for Neurodegenerative Diseases (DZNE) discuss 2-photon imaging of fluorescently labeled microglia in vivo in the context of neurodegenerative disease. They also present their recent data on the effects of different anesthetics on the microglial response to localized laser injury.
Case Study #3:
Dr. Norbert Hájos from the Hungarian Academy of Sciences presents his lab’s research into the amygdala’s role in reward-driven behavior. He shares the challenges of making single-unit recordings using silicon probes during mouse locomotion and subsequent morphological identification of active neurons in the amygdala.
Key topics covered during this webinar include:
- Requirements for stable single-cell recordings and 2-photon imaging in behaving mice
- Challenges of combining high-precision techniques with behavioral research
- Methodological considerations for improving exploratory behavior in head-fixed mice
- Quantitative analysis of microglial function using 2-photon microscopy in awake mice
- Recording neuronal activity in the amygdala of awake mice followed by morphological identification of recorded neurons
This design document proposes renovating the Avery Breathing Pacemaker electrode for use as a nerve cuff electrode to restore bladder function in individuals with spinal cord injuries. The current electrode design has limitations that could be addressed. The proposed redesigned nerve cuff would incorporate a shape memory alloy to allow self-closing around the nerve during implantation. It would also modify the lead wires to have a coiled design for flexibility and strain relief. The goal is to develop an improved nerve cuff electrode that can safely and effectively restore bladder control through electrical stimulation of peripheral nerves.
Cytotherapy for osteonecrosis of hip.acta medica internationalSanjeev kumar Jain
The document discusses the use of cytotherapy, specifically autologous bone marrow transplantation, for the treatment of osteonecrosis of the hip. It provides background on how osteonecrosis leads to a decrease in mesenchymal stem cells and impaired bone remodeling. The document then reviews studies that have found autologous bone marrow transplantation can help increase stem cell levels and promote bone repair, potentially preventing the need for hip replacement surgery.
Monitoring live cell viability Comparative studyWerden Keeler
This document compares three live cell imaging techniques: fluorescence microscopy, oblique incidence reflection microscopy, and phase contrast microscopy. It finds that oblique incidence reflection microscopy is the simplest, least expensive, and least phototoxic method, causing the least damage to live cells during long-term monitoring of cell viability. The document describes the equipment and cell lines used, including normal and cancerous cell lines tagged with fluorescent proteins or unlabeled, to evaluate the stresses induced by different illumination techniques.
Two novel flexible neural microelectrode arrays (MEAs) were designed and fabricated - Chelsea, a penetrating array for intracortical recording and stimulation, and Sabrina, a combined surface and penetrating array for micro-ECoG and intracortical recording. Glass carbon (GC) was used due to its biocompatibility, electrochemical properties, and ability to be photo-patterned. Testing showed GC has higher charge storage capacity, lower impedance, and a wider electrochemical window than platinum. It also exhibited greater corrosion resistance after aging and stimulation cycling. The flexible GC MEAs enable new MEA designs and more reliable, chronic neural signal acquisition.
Cerebral Open Flow Microperfusion (cOFM) for in vivo Cerebral Fluid Sampling ...InsideScientific
Cerebral open flow microperfusion (cOFM) is a minimally invasive, in vivo sampling technology that allows continuous long-term sampling of cerebral fluid in living animals. The decisive advantage of cOFM is that the cOFM probe is membrane–free and comprises macroscopic openings which offer the possibility for a multitude of applications without restriction regarding size, lipophilicity or protein binding effects of the collected substances. The cOFM probe is designed to elicit minimal tissue reactions and allows for reconstitution of the blood-brain barrier (BBB). Thus, cOFM can sample cerebral fluids in living and freely moving animals with intact BBB.
During this webinar, Dr. Joanna Hummer introduces cOFM and presents how cOFM is used as an in vivo sampling technology in neuroscience for drug development.
Dr. Florie Le Prieult, presents data her team collected using cOFM during a pharmacokinetic studies of therapeutic antibodies. Her study includes head-to-head comparison of cOFM and microdialysis.
Bone and Cartilage regeneration with cells and tissue engineering products - ...Enric Caceres
Bone and Cartilage regeneration with cells and tissue engineering products - Dr. Enric Cáceres - B-Debate 17/02/2015 http://www.bdebate.org/en/forum/advanced-therapies-and-regenerative-medicine-promise-21st-century
High Throughput Investigation of EC Coupling in Isolated Cardiac MyocytesInsideScientific
During this webinar sponsored by IonOptix, Michiel Helmes, PhD discusses recent advancements in instrumentation that address the shortfalls of low throughput EC coupling characterization. Specifically, Dr. Helmes explains the technology behind faster data acquisition and analysis, as well as improvements to the studies that offer more data acquisition fidelity, and automated data collection. He offers insights into best-practices for proper EC coupling measurement and highlight improvements to data handling, namely faster, automated data analysis.
Background: Measuring and analyzing calcium and contractility in isolated cardiomyocytes offers important insights into cardiac function. However, traditional methods of obtaining EC coupling data are somewhat limited to lower throughput — for many applications, particularly drug discovery research, this presents a big challenge. Additionally, low throughput data acquisition and analysis may lack the statistical power necessary to fully resolve differences, or changes, in cardiac function. Isolated myocytes can behave heterogeneously, thus greater sample numbers are essential for accurate and reliable modeling of cardiac behavior.
This document discusses bioprinting vessel-like constructs using hyaluronan hydrogels crosslinked with tetrahedral polyethylene glycol tetracrylates. Rheology testing found the crosslinked hydrogels were stiffer than PEGDA crosslinked hydrogels. Cell viability studies showed increased proliferation over 7 days for cells encapsulated in the hydrogels. The bioprinted constructs maintained cell viability for up to 4 weeks in culture. This technique provides an alternative for engineering vascularized tissue constructs.
This document discusses the use of gold nanorods (GNRs) in laser tissue welding (LTW). GNRs exhibit surface plasmon resonance that can be tuned to match laser wavelengths. This allows GNRs to efficiently absorb laser energy and heat surrounding tissue for welding. Studies demonstrated LTW of cartilage, cornea, intestine, and lens capsules using GNRs and near-infrared lasers. GNRs were incorporated into solders, patches, or hydrogels applied to tissue before laser irradiation, enabling sutureless tissue fusion and repair. LTW with GNRs showed potential for accelerated healing with minimal foreign body reactions or leaks compared to conventional suturing.
The document discusses regression following LASIK surgery. It summarizes a study examining the effects of epithelial and biomechanical changes on refractive outcomes after LASIK. The study found that these changes accounted for inaccuracies in LASIK treatment. It also determined that diagnosing regression requires analysis of layered corneal changes after LASIK using techniques like ultrasound, and that directly measuring flap and stromal thickness is important for safety when considering enhancement procedures.
Rachael Pearson is a Royal Society University Research Fellow whose research focuses on developing stem cell therapy for retinal repair and regeneration. She has established proof-of-concept for restoring vision through rod photoreceptor transplantation. Her current areas of interest include defining strategies to restore cone-mediated vision, understanding photoreceptor precursor migration in development and transplantation, and determining how to break down barriers in the degenerating retina to improve transplantation outcomes. Her lab utilizes techniques such as microscopy, stem cell culture, molecular biology, and behavioral testing to advance photoreceptor replacement therapies for treating blindness.
Efficiency of Stem Cell After Spinal Cord Injury with Clip-Compression_ Crims...Crimsonpublisherssmoaj
Efficiency of Stem Cell After Spinal Cord Injury with Clip-Compression by Tae Hoon Lee* in Crimson Publishers: Surgery Journal Impact Factor
Our experiment grafted mouse embryonic stem cell (mESC) to influence behavioral deficiency in rodent animal models of clip compressive surgery inducing spinal cord injury (SCI) of central nervous system. Our research proved the effect of grafted stem cells to the injured spinal cord region, focusing the application of mouse embryonic stem cells for regeneration of spinal cord nervous injury. Therefore, our research suggests manifest results that implantation of mouse embryonic stem cell could show behavioral improvement after severe spinal cord damage.
https://crimsonpublishers.com/smoaj/fulltext/SMOAJ.000533.php
For more open access journals in Crimson Publishers
Please click on: https://crimsonpublishers.com/
For more articles on Surgery Journal Impact Factor
Please click on link: https://crimsonpublishers.com/smoaj/index.php
Please follow the below link for our LinkedIn page
https://www.linkedin.com/company/crimsonpublishers
This document discusses lensfree microscopy and tomography techniques developed by Serhan Isikman for biomedical applications. [1] Lensfree microscopy uses holograms recorded by a sensor array to digitally reconstruct microscope images over a wide field of view in a compact, low-cost system. [2] It has been used to rapidly count red blood cells on a chip with high accuracy. [3] Lensfree optical tomography similarly uses holograms from multiple angles to computationally generate 3D images without lenses, achieving micrometer-scale resolution.
Experimental Studies of the Structure and Dynamics of Actin Networks
The document discusses experimental methods used to study actin networks, including optical trapping and particle tracking. Optical tweezers were used to generate 200 independent optical traps to manipulate particles. Particle tracking software was then used to analyze particle motion. Results showed that actin samples polymerized at 15°C and that networks healed radially inward after damage at a specific rate, with further experiments planned to study different healing based on damage type.
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La hepatitis A es una inflamación del hígado causada por el virus de la hepatitis A. Se transmite principalmente a través del agua o los alimentos contaminados. Los síntomas incluyen fiebre, malestar, pérdida del apetito, dolor abdominal y color amarillento de la piel y los ojos. La mayoría de las personas se recuperan por completo de la hepatitis A.
This document contains solutions to 20 math questions covering topics like sets, sequences, statistics, properties of numbers, and reasoning. It also provides a link to additional resources. The questions involve calculating quantities from sets and surveys, identifying patterns in sequences, determining reasoning types, and evaluating true/false statements.
Suzanne Collins nació en 1962 en Connecticut. Estudió drama en la Universidad de Indiana y más tarde amplió sus estudios en Nueva York. En 1991 comenzó a escribir literatura para niños y jóvenes, inspirándose en Alicia en el País de las Maravillas. Se hizo famosa por sus exitosas series de Los Juegos del Hambre, en Llamas y Sinsajo, que crearon un gran fenómeno fan entre el público joven.
Timea Grego ECON 662 Grad Research Paper FinalTimea Grego
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Este documento presenta una lista de indicadores financieros comúnmente utilizados para medir la liquidez, endeudamiento, actividad y rentabilidad de una empresa. Para cada indicador, se describe brevemente qué aspecto de la situación financiera de la empresa mide y cómo se calcula utilizando datos del balance general y estado de resultados. Los indicadores incluyen razones de liquidez, endeudamiento, rotación de activos e inventario, y márgenes de rentabilidad bruta, operacional y neta.
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El documento describe la evolución económica y financiera de Venezuela a lo largo de varios períodos históricos. Durante el período colonial, la economía se basaba en la agricultura y la ganadería para el comercio con España. En el período republicano se expandió el comercio con Europa y Estados Unidos. A partir de 1908 surgió la industria petrolera y Venezuela se urbanizó y modernizó. En las décadas de 1930 y 1940 se crearon el Banco Industrial de Venezuela y el Banco Central de Venezuela para regular el sistema financiero.
Timea Grego_Env Econ Term Paper 1st DraftTimea Grego
This document is a term paper that examines the environmental effects of China's accession to the World Trade Organization (WTO). It discusses how China's tariff reductions in heavy industries as part of its WTO commitments have led to increased carbon dioxide (CO2) emissions. The paper provides context on global trade patterns and China's role. It then analyzes the impacts of China's WTO commitments on its heavy industries like iron/steel and chemicals. The conclusion is that trade liberalization has contributed to China's economic growth but also rising CO2 emissions through specialization in pollution-intensive production.
3 Conversations For Designing a Self-Sustaining Talent Management Process David Lipsky, PhD
This document provides guidance on designing a self-sustaining talent management process. It emphasizes focusing conversations around why an organization exists, what its strategy is, and how it will execute its process. Sample frameworks, templates, and processes are presented to link leadership competencies to organizational goals and ensure a continuous supply of talent through succession planning and development. The goal is to create an integrated, flexible process that leads organizational growth while maintaining excellence.
Este documento describe varias enfermedades dermatológicas comunes, incluida la dermatitis atópica, el pañal, la seborrea del lactante, el miliaria, la urticaria, el impetigo, la foliculitis y la celulitis orbitaria. Proporciona información sobre las causas, síntomas y tratamiento de cada afección de la piel.
This document is a dissertation submitted by Timea Grego for the degree of Master of Science in Environmental Systems Engineering. The dissertation evaluates the use of fine sand filtration for large-scale purification of alginate for clinical applications. Alginate is a natural polymer extracted from seaweed that is used to microencapsulate liver cells. However, impurities must be removed for regulatory approval. The study aimed to determine if sand filtration could remove particulates from alginate solutions without altering the physical properties. The results showed that a dual media filter removed more particulates than a single medium filter, but filtration negatively impacted the viscosity of alginate solutions, altering hydrogel properties. In conclusion, sand filtration was not a suitable method
This document is Qing Li's resume. It summarizes her education, skills, research experience, teaching experience, honors, publications, and presentations. She has a Ph.D. in Statistics from Virginia Tech and is seeking a statistical data analyst position. Her research focuses on survival analysis, Bayesian models, and generalized linear models. She has 3 years of experience collaborating on statistical projects and 2 years teaching undergraduate statistics courses.
This study investigates exposure of the human body to electromagnetic fields from induction cooktops, both professional and domestic models. Magnetic field measurements were taken from 13 professional cooktops and 3 domestic cooktops to develop a numerical model. Current density induced in anatomical models of adults, children, pregnant women, and fetuses was then simulated. While most cooktops complied with public exposure limits at 300 mm as required by standards, many exceeded limits at closer distances and some exceeded even occupational limits. The maximum current density in users was found to significantly exceed the basic restrictions for public exposure set by ICNIRP, reaching occupational levels. Exposure of children's brains and fetal tissue was also found to exceed public exposure limits in some
MEASSuRE is a device that allows researchers to apply controlled mechanical stretch to cell or tissue cultures while simultaneously stimulating and recording electrophysiological activity. It consists of a stretchable microelectrode array incorporated with proprietary elastically stretchable microelectrodes that maintains contact with cells during stretching. MEASSuRE is the first and only commercial system that enables both electrical and mechanical stimulation of cells in vitro, as well as optical imaging of cells during stretching. It has applications in areas like tissue engineering, drug testing, and studying neurotrauma and muscle injuries.
Microelectromechanical Systems (MEMS) Based Micropumps With Appli-cation In R...SAI SIVA
In this paper we discuss the research that have been carried out till date for developing retinal implant for two major disease, age-related macular degradation (ARMD) and retinal pigmentosa (RP) and Diabetic Macular Enedema. Paper talks about the motivation for building these devices, detailed fabrication steps, evaluation and results. Retinal prosthesis and implants have tremendous potential for improving a patient’s living condi-tions and simplifying medical procedure to treat certain type of disease. At the same time development of such devices is extremely complex and takes a considerable amount of time, years to be exact to develop. The devices discussed here use Microelectromechanical System or MEMS technology to address the complexity and all the devices have an actuation mechanism embedded in a micropump for controlled release of the drug. Various test results, both animal and human trials have also been reported in the paper for each device.
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Investigating cellular metabolism with the 3D Cell ExplorerMathieuFRECHIN
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This document presents the results of a simulation study examining the propagation of electrical pulses from electrodes in nerve tissue. The study used a 3D model of an electrode cuff around nerve tissue. Simulation results showed that activating all electrodes led to activation of most fascicles. Activating two side-by-side electrodes activated the central fascicle but with lower potential. At least two electrodes spaced 90-120 degrees apart were needed to target the central fascicle. The electrode design and spacing was justified as it allows selective stimulation of different fascicles to produce desired responses without overlapping currents.
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indicator (FUCCI), a two-color (red and green) indicator that allows to monitor the cell cycle phases.
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This document describes the design and implementation of a digitally scanned laser light sheet fluorescence microscope (DSLM) at King's College London. The author elaborates on the fundamental physics and theoretical framework of DSLM and presents the optical setup, which includes a laser for illumination, digitally scanned galvanometers to control the light sheet, and a piezoelectric flexure objective scanner. Initial testing of the microscope used fluorescent beads and found a lateral resolution of 837 nm and axial resolution of 2470 nm, close to the estimated system resolution but with some systematic errors. Further imaging was limited by software and equipment issues.
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Abstract In the Bio-medical environment, for the analysis of abnormality detection in the skin including skin cancer in the epidermal layer, the traditional method used is biopsy procedure. The obtained biopsy specimens are processed by various methods viz, various orders of harmonic generations enumerate certain results resulting in the chances of some unexpected infections. Later on to overcome these infections, the followed is optical virtual biopsy procedure with higher harmonics. This yields better results than before. The watershed transform with its gradient works more accurate on the virtual specimens which is observed by microscopically with higher penetration depth. Keywords: - Harmonic generations, Watershed transform, Gradient scale, Morphological processing.
A survey on nuclear to-cytoplasmic ratio analysis using image segmentation
Wheeler_Benjamin_MyPURA
1. Benjamin Wheeler 1
A Vesicle Based Biosensor for Real Time Identification of Mild Traumatic Brain Injury.
Sponsor: Dr. Peter Searson, Materials Science and Engineering
Objective: The overall objective of this project is to design and fabricate a wearable biosensor
composed of lipid vesicles suspended in a polymeric biofilm in order to identify subjects at risk for mild
traumatic brain injury following head trauma. This sensor will be designed to allow for attachment or
insertion into the protective headwear of groups like professional athletes and military personnel. The
vesicles will be fabricated in such a way that they will
contain both a fluorescent dye and quencher. Under
normal conditions, the vesicles will hold both
molecules in proximity such that there will be no
fluorescence. However, when there is a mechanical
disturbance or event that disrupts the vesicles, the two
molecules will leak and separate enough to allow for
the fluorescence to be observed. Preliminary results
measuring vesicle leakage in an electromagnetic
shaker indicate the feasibility of this design.
Significance: Mild Traumatic Brain injury (mTBI) is
defined as a state when there is alteration of minimal duration and severity in the patient’s baseline
neurological or mental status after an injury. Annually, there is an estimate of 3.8 million concussions
occurring in the United States. Unfortunately, 50% of the injuries go unreported, making it a serious
problem for the health care field.1 mTBI is the leading cause of mortality in the active/working
population under 35 in the United States,2 and a major source of these injuries is both collegiate and
professional sports. For instance, at least 60% of those playing soccer on the collegiate level developed
symptoms compatible with a concussion during a season. Additionally, it has been reported that as high
as 18% of soldiers returning from Iraq and Afghanistan experience mild traumatic brain injury.3 In both
of these sectors, there is particular interest in the development of a functional real-time identification and
diagnostic device to aid in the development of functional return-to-action guidelines. The current
diagnosis is straightforward through computed topography (CT) and magnetic resonance imaging (MRI);
however, these clinical methods are costly, time consuming, and not readily translatable to devices for on-site
use.
A
B
Figure 1: (A) Shows how the sensor would easily be
incorporated into existing helmet design. (B) Shows
how the sensor would change fluorescence upon
vesicle rupture
When there is a significant mechanical impact to the head, there can be differential movement
between the brain and the skull. This can lead to deformation of the brain tissue, which is a primary cause
of brain damage. Also, deformation can cause structural alterations to neurons and vasculature,
generation of oxygen radicals, and/or excessive neural depolarization.4 Specifically, there can be non-specific
breakdown of the plasma membrane and the stretching and tearing of nerve fibers and small
blood vessels, which can lead to membrane retraction, extrusion of axoplasm, and formation of large
reactive swellings.
Studies show that patients who receive diagnosis and information early are less stressed and
report fewer symptoms at three months after the injury5. Currently, there are no simple diagnostic tests
for mTBI. Analysis of protein biomarkers such as S100B in serum is being explored for diagnostics.
However, these assays are not rapid. Therefore, early real-time diagnostic tools and an effective set of
“return to play guidelines” as well as other reference materials should be developed for treatment of
mTBI. My proposed device will aid medical professionals onsite during the injury to make a rapid
evaluation of the situation. Additionally, the use of a vesicle-based device is critical because of the ability
to mimic cell membrane disruption, a critical cellular mechanism in mTBI. The time saved and accurate
reflection of the physiology can be used to prevent further injury to the head as well as providing further
testing and information to the patient to attenuate the negative repercussions of mTBI.
2. Benjamin Wheeler 2
Originality: Currently in the field the only studies done to characterize the effects of force on the brain at
a cellular level have been done in vivo using animal models. These tests usually consist of either fluid
perfused through the tissue to create a pressure differential or a weight dropped from a height that impacts
the tissue with a predetermined force. Typically in these studies, a pressure of 2 to 5 atmospheres is
applied to the tissue to simulate the impact.6 These tests, while critical in understanding the mechanisms
of mTBI, cause significant harm to the animals involved and do not readily translate to a testable in vitro
model. Compared to the existing systems, the proposed system is unique in its ability to very finely
control the magnitude of force applied. Additionally, this design will allow for testing in multiple
platforms including various cell culture dishes, microfluidic devices, and cuvettes filled with vesicles in
various solutions. This will allow for easy transition to a functional field diagnostic tool.
Project Design: The objective of this project is achieved in two aims. The first aim is to characterize the
relationship between vesicle leakage and the applied mechanical force, and the second aim is to create a
wearable sensor composed of an optimized vesicle-hydrogel matrix, which can be incorporated into
protective headwear.
Aim 1: The initial aim of the project will be to
characterize the relationship between vesicle
leakage and the applied mechanical force. The
goal of this is to create leakage versus impact
calibration curves that will be used in the design
of the sensor and for calibration in the field. The
vesicles will be made using the standard method
of desiccation, re-suspension, and extrusion. In
preliminary work, vesicles have been formed
from a physiologically relevant
composition of 1-palmitoyl-2-oleoyl-sn-glycero-
3-phosphocholine (POPC),
polyethylene glycol (PEG2k), and
cholesterol. Encapsulated within these
vesicles is a solution of the dye/quencher
pair, 8-aminonapthalene-1,3,6 trisulfonic
acid (ANTS)/p-xylene-bis-pyridinium
bromide (DPX). This setup is shown in
figure 2.
To characterize the relationship
A
B
Figure 2: (A) Mechanical disturbance of the
vesicles leads to a change in the fluorescence of the
solution. (B) Shows the vesicle in greater detail
illustrating how the close proximity of dye and
A
B
Figure 3: (A) In preliminary work I have
assembled an electromagnetic shaker with a
sample stage, coupled to the cooling vacuum and
the connection to the amplifier leading out of
view. (B) Amplifier, transformer, and function
generator shown in functional arrangement. (C)
Close up of the custom stage with cuvette holder
attached.
C
between vesicle disruption and force, I
have obtained an electromagnetic shaker
(labworks et-140). The shaker has been
assembled with accompanying amplifier,
cooling fan, and function generator, as
shown in figure 3. In this configuration,
the shaker applies a displacement on the order of centimeters with variable amplitude and frequency, and
is used to model the impact force. To accompany this setup I have custom designed and fabricated a
sample stage to mount the cuvettes holding the vesicle samples to the shaker. This design can be easily
modified to allow attachment of a range of sample types, including: cuvettes, 96 well plates, and custom
made microfluidic devices. This setup accommodates a high degree of control, and allows an exact
application of impact force in agreement with previous studies and data from the literature. I will be
working with Dr. Joe Katz in mechanical engineering to relate the output of the electromagnetic shaker to
impact force.
Aim 2: The second aim of the project is to use the results previously mentioned to design and fabricate a
wearable sensor that can be easily incorporated into existing protective headwear. The sensor envisioned
3. Benjamin Wheeler 3
is a hydrogel strip composed of vesicles suspended in a polymeric matrix encased in a protective outer
layer of flexible plastic to allow for easy interpretation of fluorescence change as well as efficient
transduction of force from the impact to the sensor. It makes sense to fabricate this device using vesicles
in a gel matrix versus the aqueous suspension used to initially characterize the force -leakage relationship
for two reasons. First, and foremost, the gel will ensure even distribution of the vesicles throughout the
sensor, which will allow the sensor to be equally sensitive to impact force in any direction. Second, the
structural support provided by the gel will increase the longevity and resilience of the sensor. To create
the most effective gel for these purposes, gel composition as well as matrix and vesicle density will have
to be optimized. As a starting point, a gel composed of 5mg/mL collagen will be tested. This will allow
for an ideal balance between porosity and stiffness. To create a matrix that accurately mirrors the
mechanical properties of native tissue, the concentration of collagen as well as the introduction of other
polymers can be varied. A key aspect of this sensor is the real-time decision making it allows. To do so,
it must be easily distinguishable between a positive and negative result. To accommodate this design
parameter, the vesicle concentration will also be varied to produce an obvious response when the impact
exceeds a predetermined threshold. Beyond the fluorescence protocol previously described, other dyes
that have colorimetric function will be investigated to provide the optimal means of producing real-time
results.
Timetable: Week 1-6: Production of force-leakage calibration curves
Week 6 – 10: Optimization of the gel and vesicle composition
Week 10-14: Design and fabrication of the actual sensor and quality testing
Summary of Expected Results: Preliminary results show the force-leakage relationship can be readily
characterized and predicted based upon vesicle composition. As shown in figure 4 below, preliminary
results indicate there is at first a linear correlation between duration of force and vesicle leakage. Once
the time and steady state responses are characterized, it is expected that the magnitude of the force and
vesicle leakage can be characterized in a similar manor. It is expected at first the fluorescence will exhibit
a linear correlation with the force applied and eventually reach a plateau, as shown in the time dependent
case below at the 100-minute time point. This effect can be visualized in figure 5. Both cuvettes contain
800 μL of 100 nm diameter vesicles composed entirely of POPC. In the picture, the cuvettes are exposed
to light at the excitation wavelength of ANTS/DPX. The cuvette on the left contains undisturbed
Figure 5: Demonstration of
fluorescence readout of 100
nm POPC vesicles in
solution before and after
mechanical Figure 4: Leakage versus time for disturbance
POPC vesicles under continuous force
vesicles, while the cuvette on the right was exposed to mechanical displacement for 100 minutes. The
emission of yellow light indicates vesicle leakage, as expected from impact to the vesicles. The
combination of these results will allow for easy optimization, design, and fabrication of the sensor.
4. Benjamin Wheeler 4
Background: I have worked in Dr. Searson’s lab since May 2013, committed to understanding the
galvanotaxis of 612 glioblastoma cells under the super vision of PhD candidate Yu-Ja Huang. During my
time with the Searson Group I have learned many critical skills through the major aspects of the project
such as microfabrication, cell culture, normal light and fluorescence miscroscopy, and various biological
assays. This had led to me developing skills in and not limited to the following: photolithography,
hydrogel formation, device assembly, media preparation, stem cell culture, confocal microscopy, live and
dead cell fixing and staining, real time PCR, and cell tracking.
In addition to the hands-on laboratory work, I am also ahead on degree requirements for my junior
standing as a BME. I have already completed essential math classes such as Calculus III, Differential
Equations, and Probability and Statistics. Additionally, I have modeling experience including MATLAB
and completion of the class Models and Simulations along with preliminary course work in Systems
Bioengineering. I also have background with biology and bioengineering, as I have completed organic
chemistry, molecules and cells, and tissue engineering while currently working on Biomaterials I and
Cellular Engineering.
Should some parts of this project have complexity beyond the theoretical and practical preparation I have
obtained, I will have several experienced researches as mentors. I will be working closely with PhD
candidates Chloe Kim and Yu-Ja Huang who combined have over 8 years of research experience. Dr.
Peter Searson, the Reynolds Professor of Materials Science and Engineering and the head of the Institute
for NanoBioTechnology, will be overseeing the project. I believe the combination of these rich and
expansive has given me the ability to successfully complete this project.
Presentation and Evaluation: The results of this project will be presented in poster form, including
results of experiments carried out and reported weekly to Dr. Searson and Yu-Ja Huang at weekly
working group meetings. Project and experimental designs will be created, evaluated, and decided upon
at these meetings as well.
5. Benjamin Wheeler 5
References:
1 Hodge, Samuel D., Jr. "A Heads Up on Traumatic Brains Injuries in Sports." Journal of Health Care Law & Policy,
1 Mar. 2014. Web. 2 Oct. 2014.
2 Kovesdi, E et al. "
Update on protein biomarkers in traumatic brain injury with emphasis on clinical use in adults
2 Kovesdi, E et al. "
Update on protein biomarkers in traumatic brain injury with emphasis on clinical use in adults
and pediatrics." National Center for Biotechnology Information. U.S. National Library of Medicine, Jan. 2010. Web.
1 Oct. 2014.
3
Hoge, Charles W. "Mild Traumatic Brain Injury in U.S. Soldiers Returning from Iraq — NEJM." New England
Journal of Medicine. N.p., 31 Jan. 2008. Web. 1 Oct. 2014.
4
Dixon, C. Edward, PhD, Wiliam C. Taft, PhD, and Ronald L. Hayes, PhD. "Mechanisms of Mild Traumatic Brain
Injury. : The Journal of Head Trauma Rehabilitation." Mechanisms of Mild Traumatic Brain Injury. : The Journal of
Head Trauma Rehabilitation. Journal of Head Trauma Rehabilitation, Sept. 1993. Web. 10 Oct. 2014.
5 Ponsford, J., C. Willmott, A. Rothwell, P. Cameron, A. Kelly, R. Nelms, and C. Curran. "Impact of early
intervention on outcome following mild head injury in adults." National Center for Biotechnology Information. U.S.
National Library of Medicine, 21 Feb. 0006. Web. 09 Oct. 2014.
6 DeAngelis, M. M. "Traumatic Brain Injury Causes a Decrease in M2 Muscarinic Cholinergic Receptor Binding in
the Rat Brain." National Center for Biotechnology Information. U.S. National Library of Medicine, Aug. 1994.
Web. 10 Oct. 2014.