7,280 research outputs found

    Radiological Society of North America (RSNA) 3D printing Special Interest Group (SIG): Guidelines for medical 3D printing and appropriateness for clinical scenarios

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    Este número da revista Cadernos de Estudos Sociais estava em organização quando fomos colhidos pela morte do sociólogo Ernesto Laclau. Seu falecimento em 13 de abril de 2014 surpreendeu a todos, e particularmente ao editor Joanildo Burity, que foi seu orientando de doutorado na University of Essex, Inglaterra, e que recentemente o trouxe à Fundação Joaquim Nabuco para uma palestra, permitindo que muitos pudessem dialogar com um dos grandes intelectuais latinoamericanos contemporâneos. Assim, buscamos fazer uma homenagem ao sociólogo argentino publicando uma entrevista inédita concedida durante a sua passagem pelo Recife, em 2013, encerrando essa revista com uma sessão especial sobre a sua trajetória

    3D printing for bio-synthetic biliary stents

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    Three-dimensional (3D) printing is an additive manufacturing method that holds great potential in a variety of future patient-specific medical technologies. This project validated a novel crosslinked polyvinyl alcohol (XL-PVA) 3D printed stent infused with collagen, human placental mesenchymal stem cells (PMSCs), and cholangiocytes. The biofabrication method in the present study examined 3D printing and collagen injection molding for rapid prototyping of customized living biliary stents with clinical applications in the setting of malignant and benign bile duct obstructions. XL-PVA stents showed hydrophilic swelling and addition of radiocontrast to the stent matrix improved radiographic opacity. Collagen loaded with PMSCs contracted tightly around hydrophilic stents and dense choloangiocyte coatings were verified through histology and fluorescence microscopy. It is anticipated that design elements used in these stents may enable appropriate stent placement, provide protection of the stent-stem cell matrix against bile constituents, and potentially limit biofilm development. Overall, this approach may allow physicians to create personalized bio-integrating stents for use in biliary procedures and lays a foundation for new patient-specific stent fabrication techniques

    The Development of a Validated Clinically Meaningful Endpoint for the Evaluation of Tear Film Stability as a Measure of Ocular Surface Protection for Use in the Diagnosis and Evaluation of Dry Eye Disease

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    abstract: This dissertation presents methods for the evaluation of ocular surface protection during natural blink function. The evaluation of ocular surface protection is especially important in the diagnosis of dry eye and the evaluation of dry eye severity in clinical trials. Dry eye is a highly prevalent disease affecting vast numbers (between 11% and 22%) of an aging population. There is only one approved therapy with limited efficacy, which results in a huge unmet need. The reason so few drugs have reached approval is a lack of a recognized therapeutic pathway with reproducible endpoints. While the interplay between blink function and ocular surface protection has long been recognized, all currently used evaluation techniques have addressed blink function in isolation from tear film stability, the gold standard of which is Tear Film Break-Up Time (TFBUT). In the first part of this research a manual technique of calculating ocular surface protection during natural blink function through the use of video analysis is developed and evaluated for it's ability to differentiate between dry eye and normal subjects, the results are compared with that of TFBUT. In the second part of this research the technique is improved in precision and automated through the use of video analysis algorithms. This software, called the OPI 2.0 System, is evaluated for accuracy and precision, and comparisons are made between the OPI 2.0 System and other currently recognized dry eye diagnostic techniques (e.g. TFBUT). In the third part of this research the OPI 2.0 System is deployed for use in the evaluation of subjects before, immediately after and 30 minutes after exposure to a controlled adverse environment (CAE), once again the results are compared and contrasted against commonly used dry eye endpoints. The results demonstrate that the evaluation of ocular surface protection using the OPI 2.0 System offers superior accuracy to the current standard, TFBUT.Dissertation/ThesisPh.D. Industrial Engineering 201

    Additive manufacturing of reconstruction devices for maxillofacial surgery: design and accuracy assessment of a mandibular plate prototype

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    Additive manufacturing (AM) presents unique opportunities for medical applications and in particular in maxillofacial surgery for developing patient specific implants. The quality assessment of additive manufactured products is an essential aspect for the real introduction in health services. In this framework, the purpose of the present study is to investigate the possibility of developing prototypes of mandibular plates as preoperative surgical planning models, by verification of design, analysis of internal structure integrity and evaluation of the effects of variables involved in AM processes. A PolyJet threedimensional (3D) printing system is used in the study due to its very fine resolution. The computer aided design (CAD) models of the implants were converted to stereolithography (STL) file formats in different STL conversion resolutions and then printed using commercial prototyping polymers to observe the effect of model resolution. Finite element analysis (FEA) was conducted to study the capability of the designed mandibular plate to support the involved biomechanical loads. Micro-computed tomography (micro-CT) analysis was performed to verify the dimensions and the internal defects of the printed objects, considering that the presence of defects can affect the quality and compromise the final performance. Results were analyzed to understand the effect of the 3D printing process flow conditions on the obtained prototypes. Relative error in reference to the CAD models mainly evidenced the difference in resolution due to STL files and the effect of the design. No anomalies and defects were detected inside the evaluated samples

    Index to Library Trends Volume 38

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    published or submitted for publicatio

    Model Based Systems Engineering Approaches to Chemicals and Materials Manufacturing

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    Model-based systems engineering (MBSE) is part of a long-term trend toward model-centric approaches adopted by many engineering disciplines. This work establishes the need for an MBSE approach by reviewing the importance, complexity, and vulnerability of the U.S. chemical supply chains. The origins, work processes, modeling approaches, and supporting tools of the systems engineering discipline (SE) are discussed, along with the limitations of the current Process Systems Engineering (PSE) framework. The case is made for MBSE as a more generalizable and robust approach. Systems modeling strategies for MBSE are introduced, as well as a novel MBSE method that supports the automation tailored and extended to support the analysis of chemical supply chains. This work demonstrate the potential of MBSE approaches in chemical manufacturing by presenting two cases studies involving two different Active Pharmaceutical Ingredients (API), Atropine and Albuterol. The conclusion offers a prospectus on developmental opportunities for extracting greater benefit from MBSE in the design and management of chemical supply chains

    Perspectives and Best Practices for Artificial Intelligence and Continuously Learning Systems in Healthcare

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    Goals of this paper Healthcare is often a late adopter when it comes to new techniques and technologies; this works to our advantage in the development of this paper as we relied on lessons learned from CLS in other industries to help guide the content of this paper. Appendix V includes a number of example use cases of AI in Healthcare and other industries. This paper focuses on identifying unique attributes, constraints and potential best practices towards what might represent “good” development for Continuously Learning Systems (CLS) AI systems with applications ranging from pharmaceutical applications for new drug development and research to AI enabled smart medical devices. It should be noted that although the emphasis of this paper is on CLS, some of these issues are common to all AI products in healthcare. Additionally, there are certain topics that should be considered when developing CLS for healthcare, but they are outside of the scope of this paper. These topics will be briefly touched upon, but will not be explored in depth. Some examples include: Human Factors – this is a concern in the development of any product – what are the unique usability challenges that arise when collecting data and presenting the results? Previous efforts at generating automated alerts have often created problems (e.g. alert fatigue.) CyberSecurity and Privacy – holding a massive amount of patient data is an attractive target for hackers, what steps should be taken to protect data from misuse? How does the European Union’s General Data Protection Regulation (GDPR) impact the use of patient data? Legal liability – if a CLS system recommends action that is then reviewed and approved by a doctor, where does the liability lie if the patient is negatively affected? Regulatory considerations – medical devices are subject to regulatory oversight around the world; in fact, if a product is considered a medical device depends on what country you are in. AI provides an interesting challenge to traditional regulatory models. Additionally, some organizations like the FTC regulate non-medical devices. This paper is not intended to be a standard, nor is this paper trying to advocate for one and only one method of developing, verifying, and validating CLS systems – this paper highlights best practices from other industries and suggests adaptation of those processes for healthcare. This paper is also not intended to evaluate existing or developing regulatory, legal, ethical, or social consequences of CLS systems. This is a rapidly evolving subject with many companies, and now some countries, establishing their own AI Principles or Code of Conduct which emphasize legal and ethical considerations including goals and principles of fairness, reliability and safety, transparency around how the results of these learning systems are explained to the people using those systems5 . The intended audience of this paper are Developers, Researchers, Quality Assurance and Validation personnel, Business Managers and Regulators across both Medical Device and Pharmaceutical industries that would like to learn more about CLS best practices, and CLS practitioners wanting to learn more about medical device software development

    Engineering automated systems for pharmaceutical manufacturing: quality, regulations and business performance

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    The pharmaceutical sector is very heavily regulated Drug safety regulations form one of the pillars of this regulation. The manufacture of pharmaceuticals is carried out in an environment of onerous regulatory requirements, often from several national and international regulatory bodies. The quality systems operated by drug manufacturers and their regulatory practices have an important impact on product quality. The quality and regulatory requirements apply not only to handling of the medicinal products, but also to the physical and electronic systems used in the manufacture of those products, and extend to automated systems used to support quality assurance operations. Design, development, building and support of such systems are ultimately the responsibility of the drug manufacturer. The quality and regulatory requirements for automated systems are passed down the supply chain to suppliers. In the last two decades of the 20th century there has been a proliferation in the use of computerised and automated systems for use in, or to support manufacturing. Correspondingly, regulatory requirements have been imposed on the manufacturing industry. This work used survey research and factor analysis to establish relationships between quality and regulatory practices, and between both quality and regulatory practices and business performance for suppliers of automated systems into the pharmaceutical market. A survey instrument and an administration strategy were developed from a review of the literature. It was established empirically that quality practices and regulatory practices were strongly related. Specific facets of quality practices and regulatory practices were found to have had a significant impact on both market share and competitiveness expectations and also profit and sales expectations. Differences in practices and performance were established for various levels of automation complexity and criticality, where criticality was a function of the risk the respondent’s system posed to the manufacture of their customer’s products
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