This document summarizes a study that developed a method for cost-effective prototyping of trans aortic valve replacement (TAVR) devices. The researchers created a parametric CAD model of a TAVR stent based on existing device designs. They then used a waterjet to cut stainless steel strips into stent frames. Synthetic fabric was cut for leaflets and skirting using a CNC fabric cutter. The fabric was glued onto the frames to assemble prototypes. The developed method allows independent researchers to fabricate TAVR prototypes for studying new designs and fabrication methods to address common issues like leaks. Further testing is needed to validate prototype function and durability.
1) Transcatheter closure has become an accepted alternative to surgery for closing atrial septal defects (ASD), though large defects (>38mm) and those with deficient rims are usually referred for surgery.
2) A recent study found that the balloon assisted technique (BAT) allowed for successful device placement and closure in 92% of patients with ASDs ≥35mm, demonstrating the superiority of BAT over conventional techniques.
3) However, the study does not truly demonstrate the feasibility of transcatheter closure for very large defects, as defect size was defined arbitrarily and some patients with defects >35mm still underwent surgery. Future studies are needed to establish the optimal closure technique and 3D
This document discusses a journal article that appeared in Elsevier and summarizes its key points:
- The article reviewed 55 reported cases of carotid stent fractures from case reports, clinical studies, and an FDA database.
- Most fractures occurred in self-expandable nitinol stents, and plaque calcification may be a risk factor. No difference was seen between open and closed-cell designs.
- About 55% of fractures were associated with restenosis. Six patients presented with symptoms. Treatment included new stents, angioplasty, surgery, or follow-up in most cases.
- The incidence of fractures from studies of over 200 stents was around 9%, but larger prospective studies
1) The document describes a prospective study assessing the safety and performance of bioresorbable vascular scaffolds (BVS) in percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs).
2) 35 patients with CTOs underwent PCI with BVS implantation and were followed clinically and with imaging for 6-8 months.
3) Preliminary results found excellent mid-term patency and safety with no deaths, myocardial infarctions, or scaffold thromboses at 6-8 months follow-up.
This is initial data from the Figure 8 FlatWire Sternal Closure System. FlatWire is a simple, strong, and cost effective replacement for traditional steel wire for sternal cerclage.
TAVIguide is a software that uses patient-specific CT data and biomechanical modeling to simulate transcatheter aortic valve implantation (TAVI) procedures. It allows prediction of how different TAVI devices will fit and function within the patient's unique aortic root anatomy. Preclinical studies have shown TAVIguide's predictions of valve frame deformation, calcium displacement, paravalvular leakage, and conduction abnormalities correlate well with postoperative CT and clinical outcomes.
Ở BẸNH NHÂN NGUY CƠ CAO CÁC CẢI TIẾN VỀ CÔNG NGHỆ VÀ THUỐC CÓ GIÚP CÁC STENT ...SoM
- The document discusses stent technology evolution and whether newer-generation drug-eluting stents (DES) with different coatings are better for high-risk patients.
- Newer DES with durable polymers have improved safety outcomes compared to older DES and bare-metal stents, but are still associated with higher failure rates in high-risk patients.
- Biodegradable polymer DES like the Orsiro stent aim to reduce inflammation and promote healing to improve long-term outcomes over durable polymer DES for high-risk groups. Clinical trials show the Orsiro stent has comparable safety and efficacy to the best durable polymer DES.
1) Transcatheter closure has become an accepted alternative to surgery for closing atrial septal defects (ASD), though large defects (>38mm) and those with deficient rims are usually referred for surgery.
2) A recent study found that the balloon assisted technique (BAT) allowed for successful device placement and closure in 92% of patients with ASDs ≥35mm, demonstrating the superiority of BAT over conventional techniques.
3) However, the study does not truly demonstrate the feasibility of transcatheter closure for very large defects, as defect size was defined arbitrarily and some patients with defects >35mm still underwent surgery. Future studies are needed to establish the optimal closure technique and 3D
This document discusses a journal article that appeared in Elsevier and summarizes its key points:
- The article reviewed 55 reported cases of carotid stent fractures from case reports, clinical studies, and an FDA database.
- Most fractures occurred in self-expandable nitinol stents, and plaque calcification may be a risk factor. No difference was seen between open and closed-cell designs.
- About 55% of fractures were associated with restenosis. Six patients presented with symptoms. Treatment included new stents, angioplasty, surgery, or follow-up in most cases.
- The incidence of fractures from studies of over 200 stents was around 9%, but larger prospective studies
1) The document describes a prospective study assessing the safety and performance of bioresorbable vascular scaffolds (BVS) in percutaneous coronary intervention (PCI) for chronic total occlusions (CTOs).
2) 35 patients with CTOs underwent PCI with BVS implantation and were followed clinically and with imaging for 6-8 months.
3) Preliminary results found excellent mid-term patency and safety with no deaths, myocardial infarctions, or scaffold thromboses at 6-8 months follow-up.
This is initial data from the Figure 8 FlatWire Sternal Closure System. FlatWire is a simple, strong, and cost effective replacement for traditional steel wire for sternal cerclage.
TAVIguide is a software that uses patient-specific CT data and biomechanical modeling to simulate transcatheter aortic valve implantation (TAVI) procedures. It allows prediction of how different TAVI devices will fit and function within the patient's unique aortic root anatomy. Preclinical studies have shown TAVIguide's predictions of valve frame deformation, calcium displacement, paravalvular leakage, and conduction abnormalities correlate well with postoperative CT and clinical outcomes.
Ở BẸNH NHÂN NGUY CƠ CAO CÁC CẢI TIẾN VỀ CÔNG NGHỆ VÀ THUỐC CÓ GIÚP CÁC STENT ...SoM
- The document discusses stent technology evolution and whether newer-generation drug-eluting stents (DES) with different coatings are better for high-risk patients.
- Newer DES with durable polymers have improved safety outcomes compared to older DES and bare-metal stents, but are still associated with higher failure rates in high-risk patients.
- Biodegradable polymer DES like the Orsiro stent aim to reduce inflammation and promote healing to improve long-term outcomes over durable polymer DES for high-risk groups. Clinical trials show the Orsiro stent has comparable safety and efficacy to the best durable polymer DES.
1) The study used OCT to assess remodeling of the radial artery in 30 patients who underwent primary PCI via the transradial approach.
2) OCT imaging found a significant thickening of the intimal layer 9 months after the procedure, though mean lumen area was not significantly affected.
3) While transradial PCI was found to change the radial artery structure, there was no significant effect on vessel lumen area observed with this sample size. Larger studies are needed to confirm the results.
This document discusses CDISC standards for representing survival data from oncology clinical trials. It provides an overview of CDISC and describes the SDTM and ADaM domains that are useful for capturing efficacy endpoints involving survival, such as overall survival, progression-free survival and tumor response. Examples are given of how survival data from different patients would be represented in an ADTTE (Analysis Dataset for Time to Event) dataset according to CDISC ADaM standards.
Saturday 1030 – lombardi dissection re-entryEuro CTO Club
Bill Lombardi MD discloses financial relationships with multiple companies, including serving as a consultant for Abbott Vascular and Boston Scientific.
The document then summarizes several studies on techniques for chronic total occlusion percutaneous coronary intervention (CTO PCI). It presents data on lesion complexity scores from various CTO PCI registries and compares the hybrid algorithm approach to traditional antegrade and retrograde wiring techniques. The hybrid algorithm was shown to achieve high technical success rates even in very complex lesions.
This document discusses radiation protection for operators performing cardiac procedures. It finds that half of brain tumors in interventional cardiologists were glioblastomas located in the left temporal region, suggesting an association with occupational radiation exposure. A randomized controlled trial found that using a pelvic lead drape reduced operator left chest radiation dose by 76%, and a novel lead-free surgical cap reduced operator head radiation exposure by 81%. Adopting measures like new equipment, lowering frames per second, lead drapes and caps can significantly reduce radiation exposure for operators.
DuraGraft Vascular Conduit Preservation Solution in Patients Undergoing Coron...Karen Coviello
This study will evaluate whether pretreatment of saphenous vein grafts (SVGs) with DuraGraft, a novel solution designed to protect the endothelial layer, can reduce the development of vein graft disease (VGD) in patients undergoing coronary artery bypass grafting (CABG). The trial involves 119 patients who will each receive one SVG treated with DuraGraft and one treated with standard saline solution. Multidetector CT scans will assess changes in graft wall thickness and lumen diameter at various timepoints over 12 months to compare effects of the two treatments. The primary goals are to see if DuraGraft can decrease intimal hyperplasia and lumen loss associated with VGD. Results may provide insight
This document summarizes several studies on complications related to chronic total occlusion percutaneous coronary intervention (CTO-PCI). It reports rates of complications like perforation (0.01-2.5%) and dissection (1.5-2.6%) from past studies. It also describes a study that assessed radiation exposure in 552 CTO procedures before and after implementing a modified imaging protocol to reduce radiation. Additionally, it provides details on a study of 41 patients undergoing CTO-PCI with dual vascular access that found a 78% rate of procedural success without access-related complications. Finally, equipment entrapment complications are discussed, with one study finding an entrapment rate of 1.5%.
This document summarizes the results of a study analyzing the angiographic and clinical outcomes of patients who underwent successful percutaneous coronary intervention (PCI) to treat a chronic total occlusion (CTO). The study found that the use of everolimus-eluting stents was associated with significantly lower rates of CTO vessel reocclusion compared to first-generation drug-eluting stents. Additionally, the use of the STAR technique for CTO PCI was associated with a very high rate of vessel reocclusion despite initial success. Patients treated with everolimus-eluting stents or conventional antegrade/retrograde approaches had much higher sustained vessel patency linked to improved one-year clinical outcomes.
This document summarizes a study that quantified wall shear stress (WSS) in human conjunctival pre-capillary arterioles between 6-12 μm in diameter. The study accounted for changes in blood velocity and viscosity throughout the cardiac cycle. Average blood flow was 13-202 pl/s, wall shear rate was 587-3515 s-1, and WSS was 1.7-21.1 N/m2. Power law equations describe the relationships between diameter and flow, wall shear rate, and WSS during systole, diastole, and on average over the cardiac cycle. According to the best-fit WSS equation, average WSS decreases from 10.5 N/m2 at
Novel self expanding nitinol carotid stent - dr Krzysztof Milewskipiodof
The document describes a novel self-expanding nitinol stent with a hybrid cell design for treating carotid artery stenosis. Preclinical testing in pigs found the stent caused minimal vessel injury, low inflammation, and was fully covered by endothelium within 28 days. An initial first-in-man clinical trial showed the stent could be safely and easily implanted in patients, with good early procedural and clinical results observed. Further clinical trials are still needed to fully validate the benefits of this hybrid cell stent design.
The document describes the development of a test rig for evaluating the performance of string wound filter cartridges using water as the medium. Key points:
1) The test rig was designed to follow the single pass test method with constant flow rate conditions to measure pressure characteristics over time.
2) Several design challenges were encountered with the initial setup, including leakage issues. The design was modified to use a ready-made housing and improve flow stability.
3) Testing of sample cartridges showed increasing inlet pressure over time to maintain constant flow, validating that the rig operates as intended.
4) Results were also comparable to cartridges produced on a commercial winder, demonstrating the rig can reliably test string wound cartridge
A prosthetic is a device that replaces any missing human body part visibly and functionally. Reverse engineering is a field of engineering wherein a model and further a prototype can be generated by extracting information from previous design or available model using the advanced tools of CAD/CAM. This paper aims at exploring the needs and advantages of connecting the prosthetic industry with reverse engineering in a developing country like India for patients with lower limb amputations under the brimming concept of “Make in India”.
IRJET- Weight Optimization of API 6D 12”-150 Class Plug Valve Body by Finite ...IRJET Journal
This document summarizes research conducted to optimize the weight of an API 6D 12”-150 class plug valve body through finite element analysis and experimental testing. A 3D model of the existing valve body was created in CATIA and meshed in ANSYS Workbench. Stress analysis was performed at working pressures of 290 PSI and test pressures of 325 PSI. Modifications including reducing wall and flange thicknesses and adding fillets resulted in approximately 6.4% weight reduction while maintaining safety factors above 1. Experimental strain gauge testing validated the FEA stress results.
The document describes how a 3D printed ventilator splitter can be used to connect multiple simulated lung patients to a single ventilator during emergencies. It provides details on the ventilator splitter's design, manufacturing using 3D printing, appropriate materials, and testing results connecting up to four simulated lungs that were ventilated successfully for over 12 hours without issues. The ventilator splitter allows for increased ventilator capacity that can save lives during disasters with ventilator shortages.
The Journal of Implant & Advanced Clinical Dentistry - Oct. 2015Jay True
Amr Hosny Elkhadem, DDS, MSc
Lecturer, Prosthodontics, Faculty of Oral & Dental medicine, Cairo University
The keyless partial guidance using the simple guide kit and c-shaped sleeves is a promising economic alternative to conventional guided approach. Further investigations are required to evaluate
its accuracy and long term success rates.
www.SimpleGuideSystem.com
This document summarizes a study on the hydrodynamic characteristics of a swirling fluidized bed with a four duct plenum chamber. Large Geldart D-type particles (coffee beans and black pepper) were used. Numerical simulations were conducted using CFD software to validate experimental results. Key parameters like distributor pressure drop, minimum fluidization velocity, bed pressure drop, and radial/tangential velocities were analyzed experimentally and through simulations. The results show that a swirling fluidized bed can effectively fluidize large particles that are difficult to fluidize in a conventional bed. Pressure drops and velocities varied as expected with changes in air flow rates.
This document discusses the RECIPROC blue system for root canal preparation. It provides background on the development of nickel-titanium (NiTi) instruments and reciprocating motion. RECIPROC blue uses a single-file system with an M-wire NiTi instrument used in a reciprocating, back-and-forth motion. The system provides advantages over continuous rotation, including reduced chair time, minimized risk of instrument fracture, and maintenance of the original canal shape. The document outlines the specific design of RECIPROC blue instruments and recommendations for their use.
Companies involved in R&D are under increasing pressure to produce complex, robust designs for less cost and in less time. Simulation is widely used as a primary design tool to help meet these demands. ANSYS, the world leader in simulation software, has developed the ANSYS Workbench Environment. 3D CAD data from all major CAD systems can be seamlessly imported and simulated in this virtual testing environment.
IDAC Ireland Ltd, CAE consultants and the ANSYS Channel Partner in Ireland, have the expertise to help you to exploit these advanced technologies to produce better products in less time. Contact us today to arrange a free consultation.
The document provides a preliminary design report for a project to develop a fluid handling system and column to capture circulating tumor cells (CTCs) for a biotechnology company called Morphogenesis. It includes background on the project scope and requirements, an analysis of competitive products, concepts generated for the column design, fluid handling system, and electrical stimuli approaches. It also outlines the project timeline, identifies potential risks and recommendations, and includes calculations to specify column dimensions.
The document provides details about a device called ORCHID (Optimized Retrieval and Containment, Hand-Initiated Device) that was designed by students at the Rochester Institute of Technology to address the NASA Micro-G NExT challenge of designing a float sample grabber. The device uses 3D printed ABS and aluminum/stainless steel components to capture up to three float rock samples from separate sites in chlorinated water or microgravity environments using one-handed operation and manual power only. It was tested at the Neutral Buoyancy Lab and was found to meet all challenge requirements by safely and independently capturing samples between 1-3 inches in diameter from multiple sites.
A dry process for production of microfluidic devices based on the lamination ...Veluri Vijay Chowdary
This document describes a new microfabrication process for producing microfluidic devices using a laser printer and lamination of polyester films. The process involves printing toner onto polyester films to define microchannel patterns. The printed films are then laminated together, with the toner binding the films and leaving blank regions that become channels. This creates software-defined channels approximately 6 μm deep from a single printed layer, or twice as deep from laminating two printed layers. The resulting devices were tested and shown to have some limitations but provide an attractive low-cost option for microfluidics fabrication compared to more expensive methods.
1) The study used OCT to assess remodeling of the radial artery in 30 patients who underwent primary PCI via the transradial approach.
2) OCT imaging found a significant thickening of the intimal layer 9 months after the procedure, though mean lumen area was not significantly affected.
3) While transradial PCI was found to change the radial artery structure, there was no significant effect on vessel lumen area observed with this sample size. Larger studies are needed to confirm the results.
This document discusses CDISC standards for representing survival data from oncology clinical trials. It provides an overview of CDISC and describes the SDTM and ADaM domains that are useful for capturing efficacy endpoints involving survival, such as overall survival, progression-free survival and tumor response. Examples are given of how survival data from different patients would be represented in an ADTTE (Analysis Dataset for Time to Event) dataset according to CDISC ADaM standards.
Saturday 1030 – lombardi dissection re-entryEuro CTO Club
Bill Lombardi MD discloses financial relationships with multiple companies, including serving as a consultant for Abbott Vascular and Boston Scientific.
The document then summarizes several studies on techniques for chronic total occlusion percutaneous coronary intervention (CTO PCI). It presents data on lesion complexity scores from various CTO PCI registries and compares the hybrid algorithm approach to traditional antegrade and retrograde wiring techniques. The hybrid algorithm was shown to achieve high technical success rates even in very complex lesions.
This document discusses radiation protection for operators performing cardiac procedures. It finds that half of brain tumors in interventional cardiologists were glioblastomas located in the left temporal region, suggesting an association with occupational radiation exposure. A randomized controlled trial found that using a pelvic lead drape reduced operator left chest radiation dose by 76%, and a novel lead-free surgical cap reduced operator head radiation exposure by 81%. Adopting measures like new equipment, lowering frames per second, lead drapes and caps can significantly reduce radiation exposure for operators.
DuraGraft Vascular Conduit Preservation Solution in Patients Undergoing Coron...Karen Coviello
This study will evaluate whether pretreatment of saphenous vein grafts (SVGs) with DuraGraft, a novel solution designed to protect the endothelial layer, can reduce the development of vein graft disease (VGD) in patients undergoing coronary artery bypass grafting (CABG). The trial involves 119 patients who will each receive one SVG treated with DuraGraft and one treated with standard saline solution. Multidetector CT scans will assess changes in graft wall thickness and lumen diameter at various timepoints over 12 months to compare effects of the two treatments. The primary goals are to see if DuraGraft can decrease intimal hyperplasia and lumen loss associated with VGD. Results may provide insight
This document summarizes several studies on complications related to chronic total occlusion percutaneous coronary intervention (CTO-PCI). It reports rates of complications like perforation (0.01-2.5%) and dissection (1.5-2.6%) from past studies. It also describes a study that assessed radiation exposure in 552 CTO procedures before and after implementing a modified imaging protocol to reduce radiation. Additionally, it provides details on a study of 41 patients undergoing CTO-PCI with dual vascular access that found a 78% rate of procedural success without access-related complications. Finally, equipment entrapment complications are discussed, with one study finding an entrapment rate of 1.5%.
This document summarizes the results of a study analyzing the angiographic and clinical outcomes of patients who underwent successful percutaneous coronary intervention (PCI) to treat a chronic total occlusion (CTO). The study found that the use of everolimus-eluting stents was associated with significantly lower rates of CTO vessel reocclusion compared to first-generation drug-eluting stents. Additionally, the use of the STAR technique for CTO PCI was associated with a very high rate of vessel reocclusion despite initial success. Patients treated with everolimus-eluting stents or conventional antegrade/retrograde approaches had much higher sustained vessel patency linked to improved one-year clinical outcomes.
This document summarizes a study that quantified wall shear stress (WSS) in human conjunctival pre-capillary arterioles between 6-12 μm in diameter. The study accounted for changes in blood velocity and viscosity throughout the cardiac cycle. Average blood flow was 13-202 pl/s, wall shear rate was 587-3515 s-1, and WSS was 1.7-21.1 N/m2. Power law equations describe the relationships between diameter and flow, wall shear rate, and WSS during systole, diastole, and on average over the cardiac cycle. According to the best-fit WSS equation, average WSS decreases from 10.5 N/m2 at
Novel self expanding nitinol carotid stent - dr Krzysztof Milewskipiodof
The document describes a novel self-expanding nitinol stent with a hybrid cell design for treating carotid artery stenosis. Preclinical testing in pigs found the stent caused minimal vessel injury, low inflammation, and was fully covered by endothelium within 28 days. An initial first-in-man clinical trial showed the stent could be safely and easily implanted in patients, with good early procedural and clinical results observed. Further clinical trials are still needed to fully validate the benefits of this hybrid cell stent design.
The document describes the development of a test rig for evaluating the performance of string wound filter cartridges using water as the medium. Key points:
1) The test rig was designed to follow the single pass test method with constant flow rate conditions to measure pressure characteristics over time.
2) Several design challenges were encountered with the initial setup, including leakage issues. The design was modified to use a ready-made housing and improve flow stability.
3) Testing of sample cartridges showed increasing inlet pressure over time to maintain constant flow, validating that the rig operates as intended.
4) Results were also comparable to cartridges produced on a commercial winder, demonstrating the rig can reliably test string wound cartridge
A prosthetic is a device that replaces any missing human body part visibly and functionally. Reverse engineering is a field of engineering wherein a model and further a prototype can be generated by extracting information from previous design or available model using the advanced tools of CAD/CAM. This paper aims at exploring the needs and advantages of connecting the prosthetic industry with reverse engineering in a developing country like India for patients with lower limb amputations under the brimming concept of “Make in India”.
IRJET- Weight Optimization of API 6D 12”-150 Class Plug Valve Body by Finite ...IRJET Journal
This document summarizes research conducted to optimize the weight of an API 6D 12”-150 class plug valve body through finite element analysis and experimental testing. A 3D model of the existing valve body was created in CATIA and meshed in ANSYS Workbench. Stress analysis was performed at working pressures of 290 PSI and test pressures of 325 PSI. Modifications including reducing wall and flange thicknesses and adding fillets resulted in approximately 6.4% weight reduction while maintaining safety factors above 1. Experimental strain gauge testing validated the FEA stress results.
The document describes how a 3D printed ventilator splitter can be used to connect multiple simulated lung patients to a single ventilator during emergencies. It provides details on the ventilator splitter's design, manufacturing using 3D printing, appropriate materials, and testing results connecting up to four simulated lungs that were ventilated successfully for over 12 hours without issues. The ventilator splitter allows for increased ventilator capacity that can save lives during disasters with ventilator shortages.
The Journal of Implant & Advanced Clinical Dentistry - Oct. 2015Jay True
Amr Hosny Elkhadem, DDS, MSc
Lecturer, Prosthodontics, Faculty of Oral & Dental medicine, Cairo University
The keyless partial guidance using the simple guide kit and c-shaped sleeves is a promising economic alternative to conventional guided approach. Further investigations are required to evaluate
its accuracy and long term success rates.
www.SimpleGuideSystem.com
This document summarizes a study on the hydrodynamic characteristics of a swirling fluidized bed with a four duct plenum chamber. Large Geldart D-type particles (coffee beans and black pepper) were used. Numerical simulations were conducted using CFD software to validate experimental results. Key parameters like distributor pressure drop, minimum fluidization velocity, bed pressure drop, and radial/tangential velocities were analyzed experimentally and through simulations. The results show that a swirling fluidized bed can effectively fluidize large particles that are difficult to fluidize in a conventional bed. Pressure drops and velocities varied as expected with changes in air flow rates.
This document discusses the RECIPROC blue system for root canal preparation. It provides background on the development of nickel-titanium (NiTi) instruments and reciprocating motion. RECIPROC blue uses a single-file system with an M-wire NiTi instrument used in a reciprocating, back-and-forth motion. The system provides advantages over continuous rotation, including reduced chair time, minimized risk of instrument fracture, and maintenance of the original canal shape. The document outlines the specific design of RECIPROC blue instruments and recommendations for their use.
Companies involved in R&D are under increasing pressure to produce complex, robust designs for less cost and in less time. Simulation is widely used as a primary design tool to help meet these demands. ANSYS, the world leader in simulation software, has developed the ANSYS Workbench Environment. 3D CAD data from all major CAD systems can be seamlessly imported and simulated in this virtual testing environment.
IDAC Ireland Ltd, CAE consultants and the ANSYS Channel Partner in Ireland, have the expertise to help you to exploit these advanced technologies to produce better products in less time. Contact us today to arrange a free consultation.
The document provides a preliminary design report for a project to develop a fluid handling system and column to capture circulating tumor cells (CTCs) for a biotechnology company called Morphogenesis. It includes background on the project scope and requirements, an analysis of competitive products, concepts generated for the column design, fluid handling system, and electrical stimuli approaches. It also outlines the project timeline, identifies potential risks and recommendations, and includes calculations to specify column dimensions.
The document provides details about a device called ORCHID (Optimized Retrieval and Containment, Hand-Initiated Device) that was designed by students at the Rochester Institute of Technology to address the NASA Micro-G NExT challenge of designing a float sample grabber. The device uses 3D printed ABS and aluminum/stainless steel components to capture up to three float rock samples from separate sites in chlorinated water or microgravity environments using one-handed operation and manual power only. It was tested at the Neutral Buoyancy Lab and was found to meet all challenge requirements by safely and independently capturing samples between 1-3 inches in diameter from multiple sites.
A dry process for production of microfluidic devices based on the lamination ...Veluri Vijay Chowdary
This document describes a new microfabrication process for producing microfluidic devices using a laser printer and lamination of polyester films. The process involves printing toner onto polyester films to define microchannel patterns. The printed films are then laminated together, with the toner binding the films and leaving blank regions that become channels. This creates software-defined channels approximately 6 μm deep from a single printed layer, or twice as deep from laminating two printed layers. The resulting devices were tested and shown to have some limitations but provide an attractive low-cost option for microfluidics fabrication compared to more expensive methods.
The document describes a proposed Metacarpal Nailing System to provide a minimally invasive surgical procedure for metacarpal shaft fractures. Currently, open reduction internal fixation (ORIF) using plates requires a large incision and devascularization of the fracture site, leading to longer recovery times. The Metacarpal Nailing System uses an intramedullary rod inserted through a small incision to stabilize fractures while avoiding devascularization. It has been tested on 3D printed bone models and aims to minimize invasiveness and shorten recovery compared to ORIF. The design and testing were informed by industry standards for intramedullary devices and dimensional tolerancing.
This document describes the development of a physical model of an electromechanically actuated valve to simulate valve disease in vitro. A mono-leaflet swing valve design is presented that can control its opening profile to mimic healthy and stenotic valve states. Computational fluid dynamics analysis was used to model fluid flow through the valve design and calculate the torque on the actuator from fluid pressures. This data was then incorporated into a Simulink physical model of the electromechanical system to enable control system design and optimization. The ability of the physical model to simulate valve disease progression in a pulsatile flow test rig is discussed.
Session 3 - Retrograde approach – EUROCTO algorithmEuro CTO Club
This document provides an overview of retrograde approaches for treating chronic total occlusions (CTOs). It discusses the Euro CTO algorithm and notes that retrograde procedures are primarily used in more complex cases as determined by the J-CTO score. The success rates of retrograde procedures are around 80% overall but have increased as operators have gained more experience and new microcatheters and guidewires have been developed. Reverse controlled antegrade and retrograde subintimal tracking (Reverse CART) is the preferred retrograde technique, but different variations of Reverse CART exist depending on the characteristics of the CTO.
This paper discusses the development of single-diameter wellbore technology using solid expandable tubular systems. It describes:
1) How over 350 commercial installations helped prove the concept and technology.
2) The key benefits of single-diameter wells which reduce costs by conserving resources, saving time, and reducing environmental impact.
3) The multi-functional tool developed which can expand casing in one trip and provides contingencies like releasing connections if needed.
4) A field test in 2004 that successfully deployed and expanded 9-5/8 inch liners to test hydraulic isolation without cement. This demonstrated the viability of the single-diameter well construction method.
This document summarizes a paper presented at Offshore Europe 2005 that discusses realizing single-diameter wellbore technology using solid expandable tubulars. It provides details on:
- The development of expandable technology and its progression to enable single-diameter wells.
- A field test of the technology that successfully deployed and expanded 9-5/8 inch liners in a single trip.
- The multi-functional tool string used, including elements for expansion and contingencies.
- How the technology allows extended reach drilling and can increase reserves while reducing development costs.
This document provides information on single file systems for root canal preparation. It discusses the history of reciprocation motion and generations of rotary file systems. Specific single file systems like WaveOne and Reciproc are described in detail, including their design features and advantages. The document emphasizes that recent advances in endodontics have focused on completing root canal shaping with only one or two files to be more efficient and minimize procedural errors.
The field of transcatheter mitral valve repair (TMVr) for
mitral regurgitation (MR) is rapidly evolving. Besides the
well-established transcatheter mitral edge-to-edge repair
approach, there is also growing evidence for therapeutic
strategies targeting the mitral annulus and mitral valve
chordae. A patient-tailored approach, careful patient
selection and an experienced interventional team is crucial
in order to optimise procedural and clinical outcomes. With
further data from ongoing clinical trials to be expected,
consensus in the Heart Team is needed to address these
complexities and determine the most appropriate TMVr
therapy, either single or combined, for patients with severe
MR
This document discusses the role of 3D printing technology in orthognathic surgery. It begins by providing an overview of 3D printing and how it is used to create three-dimensional objects by building up successive layers under computer control. The document then discusses several applications of 3D printing in orthognathic surgery, including producing occlusal splints, osteotomy guides, repositioning guides, spacers, and fixation plates. It notes that 3D printed models and guides can improve surgical planning and accuracy. The document concludes by stating that 3D printing provides benefits to clinicians and patients, and that continued exploration of new materials and applications can further advance its use in orthognathic surgery.
Similar to Method for cost-effective trans aortic valve replacement device prototyping (20)
A Secure Data Transmission Scheme using Asymmetric Semi-Homomorphic Encryptio...IJAAS Team
The compressive detecting based information accumulation accomplishes with high exactness in information recuperation from less inspection which is available in sensor nodes. In this manner, the existing methods available in the literature diminish the information gathering cost and delays the existence cycle of WSNs. In this paper, a strong achievable security model for sensor network applications was initially proposed. At that point, a secure data collection conspire was displayed based on compressive detecting, which improves the information protection by the asymmetric semi-homomorphic encryption scheme, and decreases the calculation cost by inadequate compressive grid. In this case, particularly the asymmetric mechanism decreases the trouble of mystery key circulation and administration. The proposed homomorphic encryption permits the in-arrange accumulation in cipher domain, and in this manner improves the security and accomplishes the adjustment in system stack. Further, this paper focuses on estimating various network performances such as the calculation cost and correspondence cost, which remunerates the expanding cost caused by the homomorphic encryption. A real time validation on the proposed encryption scheme using AVISPA was additionally performed and the results are satisfactory.
Lossless 4D Medical Images Compression Using Adaptive Inter Slices FilteringIJAAS Team
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Method for cost-effective trans aortic valve replacement device prototyping
1. International Journal of Advances in Applied Sciences (IJAAS)
Vol. 9, No. 3, September 2020, pp. 220~226
ISSN: 2252-8814, DOI: 10.11591/ijaas.v9.i3.pp220-226 220
Journal homepage: http://ijaas.iaescore.com
Method for cost-effective trans aortic valve replacement
device prototyping
Angelique Oncale1
, Charles Taylor2
, Erika Louvier3
, G.H. Massiha4
1,3,4
Department of Industrial Technology, University of Louisiana at Lafayette, United States
2
Department of Petroleum Engineering, Louisiana State University, United States
Article Info ABSTRACT
Article history:
Received Sep 4, 2019
Revised Oct 6, 2019
Accepted May 14, 2020
Trans Aortic Valve Replacement (TAVR) has offered the cardiology sector
of health a new alternative to open heart surgeries which treat aortic stenosis.
The technologies used by TAVR manufacturers are kept private. Our
research goal was to develop a process that allows college level laboratories
to fabricate their own TAVR stents in order to research new designs
and methods of fabrication which may improve current TAVR practices. By
creating a solid model of a stent cell design in SolidWorks, we were able to
export a cutting pattern we used with a waterjet. The stent frame was then
hand polished to prepare for fabric skirting and leaflet attachment. Synthetic
ripstop fabric was cut using a commercial fabric cutting machine
and attached to the frame using a waterproof glue. Future research entails
welding techniques, improved polishing methods, and implantation into
a mechanical system. This prototype could be used for TAVR related
research and surgical training simulations.
Keywords:
Aortic stenosis
Aortic valve
Computer aided design
Computer numerical control
Trans aortic valve replacement
This is an open access article under the CC BY-SA license.
Corresponding Author:
Angelique Oncale,
Department of Industrial Technology,
University of Louisiana at Lafayette,
104 East University Avenue, Lafayette, Louisiana 70506, United States
Email: angelique.oncale1@louisiana.edu
1. INTRODUCTION
Trans Aortic Valve Replacement (TAVR) is a relatively new medical procedure that has been
evolving over nearly two decades as an alternative to open heart surgery for the treatment of Aortic Stenosis
(AS). This disease is most prevalent in the elderly with almost 27,000 patients becoming eligible for a TAVR
procedure annually [1]. The only two companies that create and sell FDA approved TAVR devices in
the United States are Edwards Lifesciences and Medtronic. Their revolutionary designs have become
an incredibly popular treatment option for high risk patients, and improved designs may become an option
for patients with lower risk profiles or those with more complex combinations of heart diseases who were
excluded from earlier trials of TAVR [2].
The treatment of aortic stenosis with valve implants became more widely used after
the development of the bi-leaflet mechanical heart valve. This type of valve is still used today, however its
popularity is decreasing with the rise of TAVR valves [3]. The TAVR valve’s predecessor, Surgical Aortic
Valve Replacement (SAVR) valves, and bi-leaflet mechanical valves both involve invasive surgeries that
many high-risk patients are unable to endure. TAVR technology is our safest option for the largest population
of patients but still has serious issues that need to be resolved.
The most common and persistent issue with TAVR valves are paravalvular leaks and paravalvular
regurgitation. A two-year analysis of post-op TAVR implantations found that regurgitation “remained
2. Int J Adv Appl Sci ISSN: 2252-8814
Method for cost-effective trans aortic valve replacement device prototyping (Angelique Oncale)
221
unchanged in 46.2% of the 143 patients studied and was worse in 22.4%” [4]. This problem is caused in large
part by a difference in stent and aortic annulus sizes [5]. The current lifespan of a TAVR, 10-15 years, is one
of the main reasons the technology is not being used for other medical conditions or younger patients. Valves
are also not yet fully retrievable and valve-in-valve implantations reduce the annulus size, affecting
hydrodynamic performance [6].
The largest hindrance to TAVR improvements is the lack of information and technology available to
independent researchers. Software techniques to better size devices and predict deployment success have
been developed but are unable to test their methods outside of simulation [7, 8]. Simplified devices for
research have made contributions to groups seeking to validate their research in the past. In 2017, a method
to create a bioprosthetic semilunar valve helped provide research-grade heart valves to independent
groups [9]. This device fabrication method was used later in 2017 to simulate a paravalvular leak for repair
using cardioscopic imaging [10]. The same method was used in 2019 to test autonomous robotic
navigation [11]. This research can provide the same means of validation for research involving
TAVR devices.
A number of issues still surround the TAVR procedure including paravalvular leaks or regurgitation,
tissue and frame durability, and valve longevity [4, 5, 12, 13]. These problems need to be resolved before this
procedure can be expanded to a larger population. The techniques used by Edwards and Medtronic to make
TAVR valves are kept private from the general public, making it difficult for researchers outside of these
corporations to study alternative fabrication methods and designs which may offer a solution to common
TAVR issues. Additionally, TAVR valves such as the Sapien 3 have an acquisition cost of about $32,500
and are only sold to medical professionals for interventional use [14]. A process for fast, cost efficient
prototyping of TAVR valves is needed to reflect the devices being used in the current industry and to
subsequently research improvements involving the technology. Without an actual device to test on
or information on its construction, there is no way to validate new developments.
The research presented here seeks to fully defines a method by which a collegiate level lab can
produce balloon expandable TAVR stent prototypes. The prototype built in this study uses easily attainable
materials such as stainless steel and nylon fabric resulting in a lower cost. Fabrication methods mentioned
here rely heavily on computer numerical control (CNC) machines including a waterjet and a consumer fabric
cutter. Contract manufacturing for waterjet cutting can be used by those without direct access to this
equipment. This process can be used to prototype existing designs or be adapted for new designs. This
prototyping method can be useful for comparison studies or studies involving a functioning TAVR valve.
2. RESEARCH METHODS AND MATERIALS
The prototype built in this study uses easily attainable materials such as stainless steel and nylon
fabric resulting in a lower cost. Fabrication methods mentioned here rely heavily on computer numerical
control (CNC) machines including a waterjet and a consumer fabric cutter. Contract manufacturing for
waterjet cutting can be used by those without direct access to this equipment. This process can be used to
prototype existing designs or be adapted for new designs.
Table 1 is showing the cell design of the TAVR stent was inspired by online images of the Sapien
XT frame. The Sapien XT comes in sizes 23mm, 26 mm, and 29 mm with heights of 14.3 mm, 17.2 mm, and
19.1 mm respectively [15]. Using the 29 mm diameter and 19.1 mm height, a parametric model of our frame
was created in Solidworks which can be viewed in both its flat pattern form and its 3D cylindrical form.
The online images showed a frame which could be divided into 3 identical sections, separated by thicker
struts which are used to anchor the leaflets. The frame’s geometry was specifically chosen to ensure its
crimping ability; it includes small spaces at the top and bottom of each cell as well as over 400 fillets to aid in
bending. The model was made using a number of variables and simple equations so that the size of the frame
and its individual parts can be easily manipulated by changing the value of a single variable. This allows
users to study the device in different sizes and define its features exactly to the user’s requirements.
The variables and equations may also be applied to different cell designs to make them parametric as well as
shown in Figure 1, Figure 2, and Figure 3.
3. ISSN: 2252-8814
Int J Adv Appl Sci, Vol. 9, No. 3, September 2020: 220 – 226
222
Table 1. CAD model variables
Global Variable Description Value/Equation Evaluates to
A Inner Diameter 29 mm 29 mm
B Overall Length (((A * 3.1415) / 3) - (2 * C) - (D)) / 3 9.21728 mm
C Strut Thickness 0.608 mm 0.608 mm
D Overall Height 1.5 mm 1.5 mm
E Large Cell Connector Diameter 19.1 mm 19.1 mm
F Cell Connector Length E * 0.75 14.325 mm
G Cell Connector Centering E / 2 9.55 mm
H Cell Distance B + C 9.82528 mm
I Linear Pattern Distance (B * 3) + D + (C * 2) 30.3678 mm
J Cell/Strut Distance C + 0.5 1.108 mm
Figure 1. Full sketch of the parametric CAD model with variables
Figures 2. Reference photograph of the Sapien
XT valve
Figures 3. Parametric model in cylindrical
configuration [16]
Figure 4 is showing flat pattern form was used to cut the stent frame from a 0.015” (0.5 mm) thick
strip of 316 stainless steel using an OMAX MAXIEM 1515 abrasive waterjet. The waterjet was chosen as the
frame fabrication method for many reasons. Contract waterjet cutting is significantly cheaper and more
widely available to the public that 3D printing or laser cutting. Fabrication with a laser may also cause heat
affected zones to become weakened; waterjets cut cold which eliminates this issue [17]. The waterjet was
equipped with a MAXJET 5i nozzle and a 0.015” diameter jewel. The abrasive material used was 150 grit
garnet and backed the stainless steel with hardboard and a 3” thick honeycomb Rhino Board. The jet’s
properties were set to 316 Stainless Steel material, 0.015” thickness, and 0.01” tool offset. The flat pattern
shows strut thicknesses to be 0.606 mm, however the tool offset allows the jet to cut tight corners needed to
produce the valve’s geometry and cuts material away from the struts reducing the thickness to a desired 0.5
mm. The frame was sanded wet with cushioned sanding pads to remove abrasive material attached to
the surface after cutting.
4. Int J Adv Appl Sci ISSN: 2252-8814
Method for cost-effective trans aortic valve replacement device prototyping (Angelique Oncale)
223
Figure 4. Stent frame cut using the OMAX waterjet
Figure 5 is showing the leaflets and fabric skirting were both made from the same synthetic
material. A nylon ripstop fabric was chosen for its water resistance, tear resistance, flexibility, and low cost.
Ripstop is also extremely thin; this type of fabric would not hinder the TAVR’s crimping ability. Using
Solidworks, a simplified leaflet design was created using a circular geometry and a leaflet graft sizing
reference [18]. The sizing reference described the grafts as semicircular with a diameter 10-15% the size of
the device’s diameter; this basic shape was kept and small tabs were added near the free edge to aid in
attachment. A circular shape was cut and folded into a semicircle to create a sturdier leaflet with a free edge
that would not fray.
Figure 5. Synthetic leaflet cut from nylon ripstop using a Cricut fabric cutter
Figure 6 is showing the fabric skirting pattern was designed so the fabric could be folded over
the frame’s struts and secured to itself. The design is a simple rectangular shape the same length as the frame
with cuts along the top to allow the fabric to be folded over the struts. There is extra length at the bottom of
the pattern so the entire bottom edge could be folded up and secured between the lower cells. Both the
leaflets and skirting were cut using a Cricut Maker, a consumer CNC fabric cutting machine. The type of
material was set to lightweight fabric and the tool used was the rotary blade. The fabric was applied to
the adhesive mat supplied with the machine and patterns were cut within seconds.
Figure 6. Fabric skirting cut from nylon ripstop using a Cricut fabric cutter
Typically, valve construction would consist of a 1-2 hours of suturing by hand. To reduce time and
skill needed to complete a valve, Loctite waterproof fabric glue was used in substitution. The stent frame was
carefully aligned on top of the fabric skirting, and each flap was folded over a strut and glued into place using
a toothpick. The bottom of the skirting was folded over the bottom struts and glued to itself. The leaflets were
glued down in the center of the circular shape to keep the free edge flat and along the circumference to keep
them closed. They were then attached to the fabric skirting using the thicker struts as a guide and the tabs at
the edge of each leaflet were glued to the adjacent leaflet. Construction of the device was reduced to
approximately 30-40 minutes.
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3. RESULTS AND ANALYSIS
This processs began with the frame of the stent. Laser cutting and 3D printing were more expensive
options compared to the waterjet. It took multiple iterations of cutting to refine the OMAX waterjet settings
to cut the frame accurately at size. The first cut was made at 125% of the desired size. The following cuts
involved a frame with simplified geometry because of the limitations of the waterjets cutting abilities.
A revision to the stent frame included wider geometries and thicker struts; we also changed the waterjet
settings to achieve the final stent frame presented here. Those first cutting attempts were welded into shape
but left significant burn marks on the surface of the frame and the rough weld spots meant we needed a more
refined welding method for the delicate frame. We used these frames to determine methods of fabric
attachment. Traditionally, fabric attachment involves hundreds of individual stitches done by hand. Trying to
do this on a frame that was already welded into its cylindrical shape proved to be extremely difficult
and inefficient. Therefore, the easiest assembly of the device included an attachment method using glue
instead of stitches and attachment of fabric before any welding was done (see Figure 7 and Figure 8). Table 2
is showing cost of supplies.
Table 2. Cost of supplies
Description Provider Price Per Unit
Highly Corrosion-Resistant 316 Stainless Steel Sheet, 2" x 5 Feet, 0.015" Thick McMaster-Carr $25.98
1.3 Oz MTN XL Hybrid Ripstop Nylon 6.6 Ripstop By the Roll $8.95
Cricut Maker Machine Cricut $369.99
Loctite 1 fl oz Vinyl Fabric & Plastic Flex Adhesive Target $2.99
Cushioned Sanding Pad Assortment, 9 Pieces McMaster-Carr $12.18
Total $420.09
Figure 7. Final assembly of the
device prototype
Figure 8. Second prototype with view of
skirting attachment
4. CONCLUSION
Further experimentation is needed to define a welding method that will not damage the fabric that is
already attached to the frame. There are no methods for crimping these prototypes other than building
a crimper or obtaining one from medical personnel. Implantation of the device into a simulated aortic valve
could produce the necessary flow data to confirm functionality. This would be an assessment not only
of the frame’s crimping and expansion ability but also the fabric’s quality. Fabric was chosen simply for its
availability and price, but if coaptation of the valve and proper flow dynamics are not achieved, the material
could easily be replaced. The fabric type and attachment methods need to be assessed for paravalvular
leaking, valvular regurgitation, and proper coaptation. The completion of this research could result in
the creation of a new bench-top training method for TAVR implantation trainees or provide a means
of validation for TAVR research involving computer modeling and simulations.
REFERENCES
[1] R. L. J. Osnabrugge, et al, “Aortic stenosis in the elderly: disease prevalence and number of candidates for
transcatheter aortic valve replacement: a meta-analysis and modeling study,” Journal of the American College of
Cardiology, vol. 62, no. 11, pp. 1002-1012, 2013.
[2] A. Horne, et al., “Transcatheter aortic valve replacement: Historical perspectives, current evidence, and future
directions,” American Heart Journal, vol. 168, no. 4, pp. 414–423, 2014.
6. Int J Adv Appl Sci ISSN: 2252-8814
Method for cost-effective trans aortic valve replacement device prototyping (Angelique Oncale)
225
[3] A. Kheradvar, et al., “Emerging Trends in Heart Valve Engineering: Part II. Novel and Standard Technologies for
Aortic Valve Replacement,” Annals of Biomedical Engineering, vol. 43, no. 4, pp. 844–857, 2014.
[4] S. K. Kodali, et al., “Two-year outcomes after transcatheter or surgical aortic velve replacement,” New England
Journal of Medicine, vol. Vol. 366, no.18, pp. 1686–1695, 2012.
[5] Détaint, L. Lepage, D. Himbert, E. Brochet, D. Messika-Zeitoun, B. Iung, and A. Vahanian, “Determinants of
significant paravalvular regurgitation after transcatheter aortic valve implantation,” JACC: Cardiovascular
Interventions, vol. 2, no. 9, pp. 821–827, 2009.
[6] O. M. Rotman, M. Bianchi, R. P. Ghosh, B. Kovarovic, and D. Bluestein, “Principles of TAVR valve design,
modelling, and testing,” Expert Review of Medical Devices, vol. 15, no. 11, pp. 771–791, 2018.
[7] A. Hosny, et al, “Pre-procedural fit-testing of TAVR valves using parametric modeling and 3D printing,” Journal
of Cardiovascular Computed Tomography, vol. 13, no. 1, pp. 21–30, 2019.
[8] Q. Wang, E. Sirois, and W. Sun, “Patient-specific modeling of biomechanical interaction in transcatheter aortic
valve deployment,” Journal of Biomechanics, vol. 45, no. 11, pp. 1965–1971, 2012.
[9] B. Rosa, et al., “A low-cost bioprosthetic semilunar valve for research, disease modelling and surgical training
applications,” Interactive CardioVascular and Thoracic Surgery, vol. 25, no. 5, pp. 785–792, 2017.
[10] B. Rosa, Z. Machaidze, M. Mencattelli, S. Manjila, et al., “Cardioscopically guided beating heart surgery:
paravalvular leak repair,” The Annals of Thoracic Surgery, vol. 104, no. 3, pp. 1074–1079, 2017.
[11] G. Fagogenis, et al, “Autonomous robotic intracardiac catheter navigation using haptic vision,” Science Robotics,
vol. 4, no. 29, pp. 1-12, 2019.
[12] W. D. Buhr, et al, “Impairment of pericardial leaflet structure from balloon-expanded valved stents,” The Journal
of Thoracic and Cardiovascular Surgery, vol. 143, no. 6, pp. 1417–1421, 2012.
[13] O. M. Rotman, M. Bianchi, R. P. Ghosh, B. Kovarovic, and D. Bluestein, “Principles of TAVR valve design,
modelling, and testing,” Expert Review of Medical Devices, vol. 15, no. 11, pp. 771–791, 2018.
[14] B. Janci and M. L. Zoler, “TAVR Wallops SAVR in cost-effectiveness for intermediate-risk patients’” Vascular
Specialist, 04-Dec-2018. [Online]. Available:
https://www.mdedge.com/vascularspecialistonline/article/150986/interventional-cardiology-surgery/tavr-wallops-
savr-cost.
[15] Edwards Lifesciences “Edwards SAPIEN XT Transcatheter Heart Valve with the Ascendra Delivery System ,”
accessdata.fda.gov, May-2014. [Online]. Available:
https://www.accessdata.fda.gov/cdrh_docs/pdf13/P130009d.pdf.
[16] E. L. Videos, “Edwards SAPIEN XT Video,” YouTube, 26-Mar-2015. [online].
Available:https://www.youtube.com/watch?v=Lcsw6y21b2o.
[17] I. Miraoui, M. Boujelbene, and E. Bayraktar, “Analysis of roughness and heat affected zone of steel plates obtained
by laser cutting,” Advanced Materials Research, vol. 974, pp. 169–173, 2014.
[18] P. E. Hammer and P. J. D. Nido, “Guidelines for sizing pericardium for aortic valve leaflet grafts,” The Annals of
Thoracic Surgery, vol. 96, no. 1, pp. e25-e27,2013.
BIOGRAPHIES OF AUTHORS
Angelique Oncale has her Master of Science in Systems Technology from
the University of Louisiana at Lafayette, College of Engineering. Her areas of research
interest are Design for Manufacturing, Computer Aided Design, and Medical
Technology. She is currently employed as and automation engineer at Noble Plastics in
Grand Coteau, Louisiana.
Charles Taylor, Ph.D., is an Assistant Research Professor of Engineering at College
of Engineering of Louisiana State University and A&M College. His areas of research
interest are the development of safety, risk and reliability practices for medical devices
targeting the cardiovascular system. He has obtained degrees in bioengineering (BS)
and biomedical engineering (PhD)
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Erika Louvier has her Master of Science in Systems Technology from the University
of Louisiana at Lafayette, College of Engineering. Her areas of research interest are
Teaching, Computer Aided Design, Metal Technology, and Manufacturing. She is
currently coordinator of Industrial Technology at South Louisiana Community College.
G. H. Massiha, Ph.D., is a Louisiana Board of Region Professor of Engineering
and Systems Technology graduate coordinator at the University of Louisiana at
Lafayette, College of Engineering. His areas of research interest are alternative
energy, robotics, and automation manufacturing.