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Biomedical engineering, Génie biomédical, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Tumeurs, Tumors, Tumeurs multiples. Tumeurs solides. Tumeurs chez l'enfant (généralités), Multiple tumors. Solid tumors. Tumors in childhood (general aspects), Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Cancer, Cáncer, Agrégat, Aggregate, Agregado, Criblage, Screening, Cernido, Dépistage, Medical screening, Descubrimiento, Médicament, Drug, Medicamento, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Tumeur maligne, Malignant tumor, and Tumor maligno

Microwell technology has revolutionized many aspects of in vitro cellular studies from 2D traditional cultures to 3D in vivo-like functional assays. However, existing lithography-based approaches are often costly and time-consuming. This study presents a rapid, low-cost prototyping method of CO2 laser ablation of a conventional untreated culture dish to create concave microwells used for generating multicellular aggregates, which can be readily available for general laboratories. Polymethylmethacrylate (PMMA), polydimethylsiloxane (PDMS), and polystyrene (PS) microwells are investigated, and each produces distinctive microwell features. Among these three materials, PS cell culture dishes produce the optimal surface smoothness and roundness. A549 lung cancer cells are grown to form cancer aggregates of controllable size from ≈40 to ≈80 μm in PS microwells. Functional assays of spheroids are performed to study migration on 2D substrates and in 3D hydrogel conditions as a step towards recapitulating the dissemination of cancer cells. Preclinical anti-cancer drug screening is investigated and reveals considerable differences between 2D and 3D conditions, indicating the importance of assay type as well as the utility of the present approach.

Biotechnology, Biotechnologies, Electronics, Electronique, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Méthodes. Procédés. Technologies, Methods. Procedures. Technologies, Méthodes et appareillages divers, Various methods and equipments, Biodétecteurs. Biocapteurs, Biosensors, Air, Aire, Biodétecteur, Biosensor, Biodetector, Cadmium, Cadmio, Cathode, Cátodo, En ligne, On line, En línea, Monitorage, Monitoring, Monitoreo, Qualité eau, Water quality, Calidad agua, Pile à combustible biologique, biofuel cell, Pile à combustible microbienne, Microbial fuel cell, and BOD

The heavy use of chemicals for agricultural, industrial and domestic purposes has increased the risk of freshwater contamination worldwide. Consequently, the demand for efficient new analytical tools for on-line and on-site water quality monitoring has become particularly urgent. In this study, a small-scale single chamber air-cathode microbial fuel cell (SCMFC), fabricated by rapid prototyping layer-by-layer 3D printing, was tested as a biosensor for continuous water quality monitoring. When acetate was fed as the rate-limiting substrate, the SCMFC acted as a sensor for chemical oxygen demand (COD) in water. The linear detection range was 3-164 ppm, with a sensitivity of 0.05 μA mM-1 cm-2 with respect to the anode total surface area. The response time was as fast as 2.8 min. At saturating acetate concentrations (COD > 164 ppm), the miniature SCMFC could rapidly detect the presence of cadmium in water with high sensitivity (0.2 μg l-1 cm-2) and a lower detection limit of only 1 μg l-1. The biosensor dynamic range was 1-25 μg l-1. Within this range of concentrations, cadmium affected only temporarily the electroactive biofilm at the anode. When the SCMFCs were again fed with fresh wastewater and no pollutant, the initial steady-state current was recovered within 12 min.

Biotechnology, Biotechnologies, Electronics, Electronique, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Mécanique fluide, Fluid mechanics, Mecánica flúido, Coeur, Heart, Corazón, Détection, Detection, Detección, Laser, Láser, Marqueur biologique, Biological marker, Marcador biológico, Microfluidique, Microfluidics, Microfluidic, Miniaturisation, Miniaturization, Miniaturización, Méthode immunologique, Immunological method, Método inmunológico, Optique, Optics, Optica, Système sur puce, System on a chip, Sistema sobre pastilla, Troponine, Troponin, Troponina, Biomarkers, Capillary, Immunoassay, and Lab-on-a-chip

Cardiovascular diseases are the most prevalent medical conditions affecting the modern world, reducing the quality of life for those affected and causing an ever increasing burden on clinical resources. Cardiac biomarkers are crucial in the diagnosis and management of patient outcomes. In that respect, such proteins are desirable to be measured at the point of care, overcoming the shortcomings of current instrumentation. We present a CO2 laser engraving technique for the rapid prototyping of a polymeric autonomous capillary system with embedded on-chip planar lenses and biosensing elements, the first step towards a fully miniaturised and integrated cardiac biosensing platform. The system has been applied to the detection of cardiac Troponin I, the gold standard biomarker for the diagnosis of acute myocardial infarction. The devised lab-on-a-chip device was demonstrated to have 24 pg/ml limit of detection, which is well within the minimum threshold for clinically applicable concentrations. Assays were completed within approximately 7―9 min. Initial results suggest that, given the portability, low power consumption and high sensitivity of the device, this technology could be developed further into point of care instrumentation useful in the diagnosis of various forms of cardiovascular diseases.

Biomedical engineering, Génie biomédical, Computer science, Informatique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Informatique; automatique theorique; systemes, Computer science; control theory; systems, Intelligence artificielle, Artificial intelligence, Reconnaissance des formes. Traitement numérique des images. Géométrie algorithmique, Pattern recognition. Digital image processing. Computational geometry, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Chirurgie orthopédique, Orthopedic surgery, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Informatique, statistique et modelisations biomedicales, Computerized, statistical medical data processing and models in biomedicine, Gestion informatisée (dossier médical, fichiers, gestion hospitalière), Computerized management (medical records, files, hospital management), Anatomie, Anatomy, Anatomía, Application médicale, Medical application, Aplicación medical, Chirurgie orthopédique, Orthopedic surgery, Cirugía ortopédica, Courbure, Curvature, Curvatura, Dépendance du temps, Time dependence, Dependencia del tiempo, Fiabilité, Reliability, Fiabilidad, Fémur, Femur, Genou, Knee, Rodilla, Image tridimensionnelle, Tridimensional image, Imagen tridimensional, Mesure, Measurement, Medida, Modèle géométrique, Geometrical model, Modelo geométrico, Modélisation, Modeling, Modelización, Méthodologie, Methodology, Metodología, Paraboloïde hyperbolique, Hyperbolic paraboloid, Paraboloide hiperbólico, Personnalisation, Customization, Personalización, Répétabilité, Repeatability, Repetibilidad, Traitement automatique, Automatic processing, Tratamiento automático, Variabilité, Variability, Variabilidad, Vision ordinateur, Computer vision, Visión ordenador, C2, C6, C8, Distal femur surface, Hyperbolic paraboloid fitting, Intercondylar fossa, Knee replacement, Patient-specific resection guides, and Whiteside line

Personalized resection guides (PRG) have been recently proposed in the domain of knee replacement, demonstrating clinical outcome similar or even superior to both manual and navigated interventions. Among the mandatory pre-surgical steps for PRG prototyping, the measurement of clinical landmarks (CL) on the bony surfaces is recognized as a key issue due to lack of standardized methodologies, operator-dependent variability and time expenditure. In this paper, we focus on the reliability and repeatability of an anterior-posterior axis, also known as Whiteside line (WL), of the distal femur proposing automatic surface processing and modeling methods aimed at overcoming some of the major concerns related to the manual identification of such CL on 2D images and 3D models. We show that the measurement of WL, exploiting the principle of mean-shifting surface curvature, is highly repeatable and coherent with clinical knowledge.

Electronics, Electronique, Optics, Optique, Telecommunications, Télécommunications, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Informatique; automatique theorique; systemes, Computer science; control theory; systems, Logiciel, Software, Systèmes informatiques et systèmes répartis. Interface utilisateur, Computer systems and distributed systems. User interface, Electronique, Electronics, Circuits électriques, optiques et optoélectroniques, Electric, optical and optoelectronic circuits, Propriétés des circuits, Circuit properties, Circuits électroniques, Electronic circuits, Convertisseurs de signal, Signal convertors, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Informatique, statistique et modelisations biomedicales, Computerized, statistical medical data processing and models in biomedicine, Informatique médicale et enseignement, Medical computing and teaching, Amplificateur, Amplifier, Amplificador, Application médicale, Medical application, Aplicación medical, Canal multiple, Multiple channel, Canal múltiple, Carte mémoire, Memory card, Tarjeta memoria, Conversion AN, AD conversion, Conversión AN, Convertisseur AN, AD converter, Convertidor AN, Echantillonnage, Sampling, Muestreo, Enregistrement donnée, Data logging, Registro datos, Etude expérimentale, Experimental study, Estudio experimental, Indice aptitude, Capability index, Indice aptitud, Interface utilisateur, User interface, Interfase usuario, Processeur 16 bits, 16 bit Processor, Procesador 16 bits, Processeur RISC, RISC processor, Procesador RISC, Puissance faible, Low power, Potencia débil, Réseau corporel, Body area network, Red de área corporal, Réseau sans fil, Wireless network, Red sin hilo, Système acquisition donnée, Data acquisition system, Sistema adquisición dato, Tension électrique, Voltage, Voltaje, Ecran tactile, Touch sensitive screens, and Pantalla táctil

A compact isolated low-power 32-channel 16-bit data-logging system around an NXP ARM processor (LPC 1768) and four of the linear technology octal analogue-to-digital converters (ADCs) LTC 1857/58/59 is designed. The system requires only 250 mA when powered at 5 V to run at full power (including a capacitive 2.8 inch touch-screen display and 32 Gb SHDC SD memory card). The sample rate is configurable up to 1 k SPS per channel as well as voltage dynamic input up to ±10 V; additionally, 32 chip select lines (SPI protocol) individually addressable and controllable while sampling to configure user-designed programmable gain amplifiers (PGAs) are available. Collaboration is being sought to improve the software capabilities, particularly to enrich the very basic user interface and to add wireless connectivity. The code is available (under the GPL licence) at our repository, the gerber file to reproduce the PCB is available (on the As-ls basis) on request. The galvanic isolation between the power supply data connection and ADC channels makes the data-logger also compatible with the main powered PCs, hence it is suitable for the implementation of medical devices at least for the prototyping and initial testing stages.

Ecology, Ecologie, Environment, Environnement, Computer science, Informatique, Pollution, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Généralités. Techniques, General aspects. Techniques, Méthodes et techniques (échantillonnage, marquage, piégeage, modélisation...), Methods and techniques (sampling, tagging, trapping, modelling...), Modèle, Models, Modelo, Modélisation, Modeling, Modelización, Système information géographique, Geographic information system, Sistema información geográfica, Distributed hydrologic model, GIS, PIHM, PIHMgis, and Shared geodata model

Distributed, physics-based hydrologic models require spatially explicit specification of parameters related to climate, geology, land-cover, soil, and topography. Extracting these parameters from national geodatabases requires intensive data processing. Furthermore, mapping these parameters to model mesh elements necessitates development of data access tools that can handle both spatial and temporal datasets. This paper presents an open-source, platform independent, tightly coupled GIS and distributed hydrologic modeling framework, PIHMgis (www.pihm.psu.edu), to improve model-data integration. Tight coupling is achieved through the development of an integrated user interface with an underlying shared geodata model, which improves data flow between the PIHMgis data processing components. The capability and effectiveness of the PIHMgis framework in providing functionalities for watershed delineation, domain decomposition, parameter assignment, simulation, visualization and analyses, is demonstrated through prototyping of a model simulation. The framework and the approach are applicable for watersheds of varied sizes, and offer a template for future GIS-Model integration efforts.

Cognition, Genetics, Génétique, Applied physiology, ergonomics sports medicine, Physiologie appliquée, ergonomie, sport, Psychology, psychopathology, psychiatry, Psychologie, psychopathologie, psychiatrie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Psychologie. Psychophysiologie, Psychology. Psychophysiology, Psychologie du travail, Occupational psychology, Ergonomie. Facteur humain, Ergonomics. Human factors, Sciences medicales, Medical sciences, Physiologie humaine appliquee a l'etude des populations et des conditions de vie. Ecophysiologie humaine, Human physiology applied to population studies and life conditions. Human ecophysiology, Physiologie appliquée, Applied physiology, Ergonomie. Poste de travail. Physiologie du travail, Ergonomics. Work place. Occupational physiology, Psychologie. Psychanalyse. Psychiatrie, Psychology. Psychoanalysis. Psychiatry, Contrôle moteur, Motor control, Control motor, Ergonomie, Ergonomics, Ergonomía, Facteur humain, Human factor, Factor humano, Homme, Human, Hombre, Localisation objet, Object location, Localización objeto, Réalité virtuelle, Virtual reality, Realidad virtual, Tâche manuelle, Manual task, Tarea manual, CAVE, physical interface, simulation, and virtual reality

Objective: In this study, we compared how users locate physical and equivalent three-dimensional images of virtual objects in a cave automatic virtual environment (CAVE) using the hand to examine how human performance (accuracy, time, and approach) is affected by object size, location, and distance. Background: Virtual reality (VR) offers the promise to flexibly simulate arbitrary environments for studying human performance. Previously, VR researchers primarily considered differences between virtual and physical distance estimation rather than reaching for close-up objects. Method: Fourteen participants completed manual targeting tasks that involved reaching for corners on equivalent physical and virtual boxes of three different sizes. Predicted errors were calculated from a geometric model based on user interpupillary distance, eye location, distance from the eyes to the projector screen, and object. Results: Users were 1.64 times less accurate (p < .001) and spent 1.49 times more time (p = .01) targeting virtual versus physical box corners using the hands. Predicted virtual targeting errors were on average 1.53 times (p < .05) greater than the observed errors for farther virtual targets but not significantly different for close-up virtual targets. Conclusion: Target size, location, and distance, in addition to binocular disparity, affected virtual object targeting inaccuracy. Observed virtual box inaccuracy was less than predicted for farther locations, suggesting possible influence of cues other than binocular vision. Application: Human physical interaction with objects in VR for simulation, training, and prototyping involving reaching and manually handling virtual objects in a CAVE are more accurate than predicted when locating farther objects.

Control theory, operational research, Automatique, recherche opérationnelle, Computer science, Informatique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Recherche operationnelle. Gestion, Operational research. Management science, Recherche opérationnelle et modèles formalisés de gestion, Operational research and scientific management, Ordonnancement, Scheduling, sequencing, Informatique; automatique theorique; systemes, Computer science; control theory; systems, Informatique théorique, Theoretical computing, Recherche information. Graphe, Information retrieval. Graph, Logiciel, Software, Simulation, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Sante publique. Hygiene-medecine du travail, Public health. Hygiene-occupational medicine, Santé publique. Hygiène, Public health. Hygiene, Etablissements sanitaires et sociaux, Health and social institutions, Economie. Gestion, Economy. Management, Conception assistée, Computer aided design, Concepción asistida, Court terme, Short term, Corto plazo, Dépendance, Dependence, Dependencia, Modélisation, Modeling, Modelización, Métaanalyse, Metaanalysis, Meta-análisis, Métamodèle, Metamodel, Metamodelo, Ordonnancement, Scheduling, Reglamento, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Réseau Pétri, Petri net, Red Petri, Santé publique, Public health, Salud pública, Simulation ordinateur, Computer simulation, Simulación computadora, Modèle organisation, Organizational models, Modelo organizacional, Health care, Petri nets (PNs), modeling, rapid prototyping, and simulation

In this paper, we propose a new modeling methodology named MedPRO for addressing organization problems of health care systems. It is based on a metamodel with three different views: process view (care pathways of patients), resource view (activities of relevant resources), and organization view (dependence and organization of resources). The resulting metamodel can be instantiated for a specific health care system and be converted into an executable model for simulation by means of a special class of Petri nets (PNs), called Health Care Petri Nets (HCPNs). HCPN models also serve as a basis for short-term planning and scheduling of health care activities. As a result, the MedPRO methodology leads to a fast-prototyping tool for easy and rigorous modeling and simulation of health care systems. A case study is presented to show the benefits of the MedPRO methodology.

Computer science, Informatique, Psychology, psychopathology, psychiatry, Psychologie, psychopathologie, psychiatrie, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Informatique; automatique theorique; systemes, Computer science; control theory; systems, Logiciel, Software, Systèmes informatiques et systèmes répartis. Interface utilisateur, Computer systems and distributed systems. User interface, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Psychologie. Psychophysiologie, Psychology. Psychophysiology, Psychologie sociale, Social psychology, Interactions sociales. Communication. Processus de groupe, Social interactions. Communication. Group processes, Psychologie. Psychanalyse. Psychiatrie, Psychology. Psychoanalysis. Psychiatry, Acceptation, Acceptance, Aceptación, Actionneur, Actuator, Accionador, Court terme, Short term, Corto plazo, Interaction sociale, Social interaction, Interacción social, Interface utilisateur, User interface, Interfase usuario, Long terme, Long term, Largo plazo, Méthode itérative, Iterative method, Método iterativo, Processus conception, Design process, Proceso concepcion, Sensibilité tactile, Tactile sensitivity, Sensibilidad tactil, Technologie communication, Communication technology, Tecnología comunicacíon, Téléopération, Remote operation, Teleacción, Interface tangible, Tangible interface, Interfase tangible, Haptic interpersonal communication, Kiss transmission, Kissenger, Remote tactile communication, and Tangible user interface

Intimate interactions between remotely located individuals are not well supported by conventional communication tools, mainly due to the lack of physical contact. Also, haptic research has not focused on the use of a kiss as a mode of interaction that maintains intimacy in long distance relationships. In this study, we designed and developed a haptic device called Kissenger (Kiss-Messenger) for this issue. Kissenger is an interactive device that provides a physical interface for transmitting a kiss between two remotely connected people. Each device is paired with another and the amount of force and shape of the kiss by the user is sensed and transmitted to another device that is replicated using actuators. Kissenger is designed to augment already existing remote communication technologies. Challenges in the design and development of the system are addressed through an iterative design process involving constant evaluation by users after each stage. The devices are evaluated through a short- and a long-term user study with remotely located couples. The results point to an initial acceptance of the device with feedback from the users on directions to improve the overall experience. This study discusses potential issues that designers should be aware of when prototyping for remote intimate interactions.

Mechanical engineering, Génie mécanique, Materials, Matériaux, Metrology and instrumentation, Métrologie et instrumentation, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Radiotherapie. Traitement instrumental. Physiotherapie. Reeducation. Readaptation, orthophonie, crenotherapie. Traitement dietetique et traitements divers (generalites), Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects), Technologie. Biomatériaux. Equipements. Matériel. Appareillage, Technology. Biomaterials. Equipments. Material. Instrumentation, Adhérence, Adhesion, Adherencia, Aire superficielle, Surface area, Area superficial, Analyse structurale, Structural analysis, Análisis estructural, Biomimétique, Biomimetics, Cavité dans réseau, Void, Cavidad en red, Forme sphérique, Spherical shape, Forma esférica, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Matériau poreux, Porous material, Material poroso, Prototype, Prototipo, Résistance mécanique, Strength, Resistencia mecánica, Additive manufacture, Conventional TPMS scaffolds, Multi-material TPMS tissue models, Multi-void TPMS scaffolds, Organ printing, and Surface area to volume ratio

Creating biophysically and biologically desirable porous scaffolds has always been one of the greatest challenges in tissue engineering (TE). Advanced additive manufacture (AM) methods such as three-dimensional (3D) printing techniques have established remarkable improvements in the fabrication of porous scaffolds and structures close in architecture to biological tissue. Such fabrication techniques have opened new areas of research in TE. Recently, it was shown that porous scaffolds which are mathematically designed by using triply periodic minimal surface (TPMS) pore geometry and fabricated through 3D printing techniques have remarkably high cell viability and mechanical strength when compared with conventional scaffolds. The enhanced cell adhesion, migration, and proliferation of TPMS-based scaffolds arise from the high surface area to volume ratio (SA/v ratio) that is a basic and fundamental concept of biology. Here, we report the design of multi-void TPMS-based scaffolds that dramatically increase the SA/V ratio of conventional TPMS scaffolds. Our findings suggest that the proposed novel design methodology can be applied to create a variety of computational models for prototyping and printing of biomimetic scaffolds and bioartificial tissues.

Mechanical engineering, Génie mécanique, Materials, Matériaux, Metrology and instrumentation, Métrologie et instrumentation, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Radiotherapie. Traitement instrumental. Physiotherapie. Reeducation. Readaptation, orthophonie, crenotherapie. Traitement dietetique et traitements divers (generalites), Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects), Technologie. Biomatériaux. Equipements. Matériel. Appareillage, Technology. Biomaterials. Equipments. Material. Instrumentation, Biomimétique, Biomimetics, Conception assistée, Computer aided design, Concepción asistida, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Impression, Printing, Impresión, Organe artificiel, Artificial organ, Organo artificial, Procédé fabrication, Manufacturing process, Procedimiento fabricación, Prototype, Prototipo, Additive manufacturing, Artificial tissues, Computer-aided tissue engineering, Organ printing, and Porous scaffolds

Advances introduced by additive manufacturing (AM) methods referred to as solid freedom fabrication (SFF) or rapid protofJping (RP) methods have significantly improved the ability to fabricate porous scaffold structures close in architectures to biological tissues. These technologies have led to the development of innovative porous scaffolds and spatially complex artificial tissues. However, the current approaches face many challenges, such as the lack of an effective design software for printing and prototyping of tissues and scaffolds. In this article, a brief overview of the recent trends and challenges in computer-aided tissue engineering is provided Future directions are also suggested in order to discuss the challenging technological barriers and provide the overall feasibility of prototyping and printing of biomimetic scaffolds and bioartificial tissues or organs.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Formes d'application et semiproduits, Forms of application and semi-finished materials, Matériaux composites, Composites, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Biocompatibilité, Biocompatibility, Biocompatibilidad, Biomatériau, Biomaterial, Caprolactone polymère, Polycaprolactone, Caprolactona polímero, Chlorure de sodium, Sodium chloride, Sodio cloruro, Elimination, Eliminación, Etude expérimentale, Experimental study, Estudio experimental, Fabrication, Manufacturing, Fabricación, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Lactone polymère, Lactone polymer, Lactona polímero, Macroporosité, Macroporosity, Macroporosidad, Matériau composite, Composite material, Material compuesto, Matériau poreux, Porous material, Material poroso, Morphologie, Morphology, Morfología, Multiplication cellulaire, Cell proliferation, Multiplicación celular, Polymère aliphatique, Aliphatic polymer, Polímero alifático, Porosité, Porosity, Porosidad, Propriété biologique, Biological properties, Propiedad biológica, Propriété mécanique, Mechanical properties, Propiedad mecánica, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Résistance compression, Compressive strength, Resistencia compresión, Echafaudage tissulaire, Fabrication forme libre solide, Moule perforé, biomedical applications, manufacturing, and porous materials

In this study, a salt-leaching using powder (SLUP) scaffold with penetrated macropores was proposed to enhance cell proliferation. A SLUP scaffold is a salt-leaching scaffold with an arbitrary pore configuration. Although SLUP scaffolds have several advantage over traditional salt-leaching scaffolds, the cell ingrowth might be poor compared with solid freeform fabrication scaffolds, which have well-interconnected pores. We therefore proposed SLUP scaffolds with penetrated macropores to assist the cell ingrowth. First, polycaprolactone (PCL) powders with a grain size of 63-100 fim and NaCl powders with a grain size of 100-180 μm were prepared. Next, a uniformly perforated mold was fabricated using an rapid prototyping (RP) system. Then, 500-, 820-, or 1200-μm-diameter needles were inserted into the holes of the RP mold. Subsequently, the mold was filled with a mixed powder of PCL/NaCl (30: 70 vol %). The mold was then heated in the oven at 100°C for 30 min, and both the needles and the mold were removed from the PCL/NaCl mixture. Then, the PCL/NaCl mixture was soaked in DI water for 24 h to leach out NaCl particles and dried in a vacuum desiccator for 24 h. The porosity of fabricated scaffolds was calculated using a simple equation, and the compressive stiffness was measured using a universal testing machine. Moreover, each scaffold (10 × 10 × 10 mm3) was seeded with 100,000 Saos-2 cells and cultured for 14 days. The cell proliferation characteristics were assessed using a CCK-8 assay at 1, 7, and 14 days for comparison with the control scaffolds, that is, the SLUP scaffolds with no penetrated macropores.

Biomedical engineering, Génie biomédical, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Applications et implications industrielles. Aspects économiques, Industrial applications and implications. Economical aspects, Santé. Industrie pharmaceutique, Health. Pharmaceutical industry, Divers, Miscellaneous, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Système ostéoarticulaire, Osteoarticular system, Sistema osteoarticular, Biomatériau, Biomaterial, Caprolactone polymère, Polycaprolactone, Caprolactona polímero, Cellule géante, Giant cell, Célula gigante, Corps étranger, Foreign body, Cuerpo extraño, Dégradation biologique, Biodegradation, Degradación biológica, Echafaudage, Scaffold, Andamiaje, Etude expérimentale, Experimental study, Estudio experimental, Génie biomédical, Biomedical engineering, Ingeniería biomédica, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, In vitro, In vivo, Lactone polymère, Lactone polymer, Lactona polímero, Os, Bone, Hueso, Polymère aliphatique, Aliphatic polymer, Polímero alifático, Réparation, Repair, Reparación, Tissu osseux, Osseous tissue, Tejido óseo, Traitement surface, Surface treatment, Tratamiento superficie, biodegradation, bone tissue engineering, foreign body giant cell, poly-ε-caprolactone, and scaffold

A porcine calvaria defect study was carried out to investigate the bone repair potential of three-dimensional (3D)-printed poly-ε-caprolactone (PCL) scaffolds embedded with nanoporous PCL. A microscopic grid network was created by rapid prototyping making a 3D-fused deposition model (FDM-PCL). Afterward, the FDM-PCL scaffolds were infused with a mixture of PCL, water, and 1,4-dioxane and underwent a thermal-induced phase separation (TIPS) followed by lyophilization. The TIPS process lead to a nanoporous structure shielded by the printed microstructure (NSP-PCL). Sixteen Landrace pigs were divided into two groups with 8 and 12 weeks follow-up, respectively. A total of six nonpenetrating holes were drilled in the calvaria of each animal. The size of the cylindrical defects was h 10 mm and Ø 10 mm. The defects were distributed randomly using following groups: (a) NSP-PCL scaffold, (b) FDM-PCL scaffold, (c) autograft, (d) empty defect, (a1) NSP-PCL scaffold + autologous mononuclear cells, and (a2) NSP-PCL scaffold + bone morphogenetic protein 2. Bone volume to total volume was analyzed using microcomputed tomography (μCT) and histomorphometry. The μCT and histological data showed significantly less bone formation in the NSP-PCL scaffolds in all three variations after both 8 and 12 weeks compared to all other groups. The positive autograft control had significantly higher new bone formation compared to all other groups except the FDM-PCL when analyzed using histomorphometry. The NSP-PCL scaffolds were heavily infiltrated with foreign body giant cells suggesting an inflammatory response and perhaps active resorption of the scaffold material. The unmodified FDM-PCL scaffold showed good osteoconductivity and osseointegration after both 8 and 12 weeks.

Biomedical engineering, Génie biomédical, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Applications et implications industrielles. Aspects économiques, Industrial applications and implications. Economical aspects, Santé. Industrie pharmaceutique, Health. Pharmaceutical industry, Divers, Miscellaneous, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Biomatériau, Biomaterial, Echafaudage, Scaffold, Andamiaje, Génie biomédical, Biomedical engineering, Ingeniería biomédica, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Os spongieux, Spongious bone, Hueso esponjoso, Perméabilité, Permeability, Permeabilidad, Propriété transport, Transport properties, Propiedad transporte, Prototypage rapide, Rapid prototyping, Prototipificación rápida, permeability, rapid prototyping, synthetic scaffold, tissue engineering, and trabecular bone

In this work, various three-dimensional (3D) scaffolds were produced via micro-stereolithography (μ-SLA) and 3D printing (3DP) techniques. This work demonstrates the advantages and disadvantages of these two different rapid prototyping methods for production of bone scaffolds. Compared to 3DP, SLA provides for smaller feature production with better dimensional resolution and accuracy. The permeability of these structures was evaluated experimentally and via numerical simulation utilizing a newly derived Kozeny-Carman based equation for intrinsic permeability. Both experimental and simulation studies took account of porosity percentage, pore size, and pore geometry. Porosity content was varied from 30% to 70%, pore size from 0.34 mm to 3 mm, and pore geometries of cubic and hexagonal closed packed were examined. Two different fluid viscosity levels of 1 mpa.s and 3.6 mPa.s were used. The experimental and theoretical results indicated that permeability increased when larger pore size, increased fluid viscosity, and higher percentage porosity were utilized, with highest to lowest degree of significance following the same order. Higher viscosity was found to result in permeabilities 2.2 to 3.3 times higher than for water. This latter result was found to be independent of pore morphology type. As well as demonstrating method for determining design parameters most beneficial for scaffold structure design, the results also illustrate how the variations in patient's blood viscosity can be extremely important in allowing for permeability through the bone and scaffold structures.

Biomedical engineering, Génie biomédical, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Applications et implications industrielles. Aspects économiques, Industrial applications and implications. Economical aspects, Santé. Industrie pharmaceutique, Health. Pharmaceutical industry, Divers, Miscellaneous, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Biomatériau, Biomaterial, Caprolactone polymère, Polycaprolactone, Caprolactona polímero, Génie biomédical, Biomedical engineering, Ingeniería biomédica, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Lactone polymère, Lactone polymer, Lactona polímero, Polymère aliphatique, Aliphatic polymer, Polímero alifático, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Echafaudage tissulaire, Impression tridimensionnelle, Polymère biodégradable, poly(ε-caprolactone), pore architecture, pore gradient, rapid prototyping, and scaffold fabrication

The fabrication of scaffolds for tissue engineering requires elements of customization depending on the application and is often limited due to the flexibility of the processing technique. This investigation seeks to address this obstacle by utilizing an open-source three-dimensional printing (3DP) system that allows vast customizability and facilitates reproduction of experiments. The effects of processing parameters on printed poly(ε-caprolactone) scaffolds with uniform and gradient pore architectures have been characterized with respect to fiber and pore morphology and mechanical properties. The results demonstrate the ability to tailor the fiber diameter, pore size, and porosity through modification of pressure, printing speed, and programmed fiber spacing. A model was also used to predict the compressive mechanical properties of uniform and gradient scaffolds, and it was found that modulus and yield strength declined with increasing porosity. The use of open-source 3DP technologies for printing tissue-engineering scaffolds provides a flexible system that can be readily modified at a low cost and is supported by community documentation. In this manner, the 3DP system is more accessible to the scientific community, which further facilitates the translation of these technologies toward successful tissue-engineering strategies.

Biomedical engineering, Génie biomédical, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Informatique, statistique et modelisations biomedicales, Computerized, statistical medical data processing and models in biomedicine, Modèles et simulation, Models and simulation, Chirurgie, Surgery, Cirugía, Biomatériau, Biomaterial, Cicatrisation, Cicatrization, Cicatrización, Dispositif, Device, Dispositivo, Fermeture, Closure, Cerradura, Génie biomédical, Biomedical engineering, Ingeniería biomédica, Larynx, Laringe, Microchirurgie, Microsurgery, Microcirugía, Modélisation, Modeling, Modelización, Méthode, Method, Método, Plaie, Wound, Herida, Simulation, Simulación, Traitement, Treatment, Tratamiento, biodegradable materials, computational methods, laryngeal microsurgery, virtual prototyping, and wound healing

Biodegradable materials have been used as wound closure materials. It is important for these materials to enhance wound healing when the wound is vulnerable, and maintain wound closure until the wound is heal. This article studies the degradation process of bioresorbable magnesium micro-clips for wound closure in voice/laryngeal microsurgery. A novel computational approach is proposed to model degradation of the biodegradable micro-clips. The degradation process that considers both material and geometry of the device as well as its deployment is modeled as an energy minimization problem that is iteratively solved using active contour and incremental finite element methods. Strain energy of the micro-clip during degradation is calculated with the stretching and bending functions in the active contour formulation. The degradation rate is computed from strain energy using a transformation formulation. By relating strain energy to material degradation, the degradation rates and geometries of the micro-clip during degradation can be represented using a simulated degradation map. Computer simulation of the degradation of the micro-clip presented in the study is validated by in vivo and in vitro experiments.

Biomedical engineering, Génie biomédical, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Applications et implications industrielles. Aspects économiques, Industrial applications and implications. Economical aspects, Santé. Industrie pharmaceutique, Health. Pharmaceutical industry, Divers, Miscellaneous, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Génie biomédical, Biomedical engineering, Ingeniería biomédica, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Stéréolithographie, Stereolithography, and Stereolitografia

Several recent research efforts have focused on use of computer-aided additive fabrication technologies, commonly referred to as additive manufacturing, rapid prototyping, solid freeform fabrication, or three-dimensional printing technologies, to create structures for tissue engineering. For example, scaffolds for tissue engineering may be processed using rapid prototyping technologies, which serve as matrices for cell ingrowth, vascularization, as well as transport of nutrients and waste. Stereolithography is a photopolymerization-based rapid prototyping technology that involves computer-driven and spatially controlled irradiation of liquid resin. This technology enables structures with precise microscale features to be prepared directly from a computer model. In this review, use of stereolithography for processing trimethylene carbonate, polycaprolactone, and poly(D,L-lactide) poly(propylene fumarate)-based materials is considered. In addition, incorporation of bioceramic fillers for fabrication of bioceramic scaffolds is reviewed. Use of stereolithography for processing of patient-specific implantable scaffolds is also discussed. In addition, use of photopolymerization-based rapid prototyping technology, known as two-photon polymerization, for production of tissue engineering scaffolds with smaller features than conventional stereolithography technology is considered.

Polymers, paint and wood industries, Polymères, industries des peintures et bois, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Formes d'application et semiproduits, Forms of application and semi-finished materials, Matériaux composites, Composites, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Chirurgie (generalites). Transplantations, greffes d'organes et de tissus. Pathologie des greffons, Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases, Technologie. Biomatériaux. Equipements, Technology. Biomaterials. Equipments, Apatite hydroxylée, Hydroxyapatite, Hidroxiapatito, Biomatériau, Biomaterial, Copolymère aliphatique, Aliphatic copolymer, Copolímero alifático, Copolymère triséquencé, Triblock copolymer, Copolímero trisecuencia, Effet concentration, Concentration effect, Efecto concentración, Effet mémoire forme, Shape memory effect, Efecto memoria forma, Ethylène oxyde copolymère, Ethylene oxide copolymer, Etileno óxido copolímero, Etude expérimentale, Experimental study, Estudio experimental, Fabrication, Manufacturing, Fabricación, Forme cylindrique, Cylindrical shape, Forma cilíndrica, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Lactique acide copolymère, Lactic acid copolymer, Láctico ácido copolímero, Matériau composite, Composite material, Material compuesto, Matériau poreux, Porous material, Material poroso, Morphologie, Morphology, Morfología, Polymère amphiphile, Amphiphilic polymer, Polímero amfifilo, Propriété dynamomécanique, Dynamic mechanical properties, Propiedad dinamomecánica, Propriété mécanique, Mechanical properties, Propiedad mecánica, Prototypage rapide, Rapid prototyping, Prototipificación rápida, Tissu osseux, Osseous tissue, Tejido óseo, biodegradable, hydroxyapatite, rapid prototyping, shape-memory polymers, and tissue engineering

Biodegradable polymer/hydroxyapatite (HA) composites are desired for skeletal tissue engineering. When engineered with thermally responsive shape-memory properties, they may be delivered in a minimally invasive temporary shape and subsequently triggered to conform to a tissue defect. Here, the shape-memory properties of thermoplastic amphiphilic poly(D,L-lactic acid-co-ethylene glycol-co-D,L-lactic acid) (PELA) (Mw = 120 kDa) and HA-PELA composites are reported. These materials can be cold-deformed and stably fixed into temporary shapes at room temperature and undergo rapid shape recovery (<3 s) at 50 °C. Stable fixation (>99% fixing ratio) of large deformations is achieved at -20 °C. While the shape recovery from tensile deformations slows with higher HA contents, all the composites (up to 20 wt% HA) achieve high shape recovery (>90%) upon equilibration for 10 min at 50 °C. The permanent shapes of HA-PELA can be reprogrammed at 50 °C, and macroporous shape-memory scaffolds can be fabricated by rapid prototyping.

Biotechnology, Biotechnologies, Analytical chemistry, Chimie analytique, Mechanics acoustics, Mécanique et acoustique, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Méthodes. Procédés. Technologies, Methods. Procedures. Technologies, Méthodes et appareillages divers, Various methods and equipments, Mécanique fluide, Fluid mechanics, Mecánica flúido, Choix matériau, Material selection, Selección material, Fabrication, Manufacturing, Fabricación, Microfluidique, Microfluidics, Microfluidic, Photolithographie, Photolithography, Fotolitografía, Polymère, Polymer, Polímero, Système sur puce, System on a chip, Sistema sobre pastilla, Lab on chip, OSTE polymer, and Surface modification

A new and easy-to-use method that allows for mold-free and rapid prototyping of microfluidic devices, comprising channels, access holes, and surface-modified patterns, is presented. The innovative method is based on direct photolithographic patterning of an off-stoichiometry thiol-ene (OSTE) polymer formulation, tailor-made for photolithography, which offers unprecedented spatial resolution and allows for efficient, robust and reliable, room temperature surface modification and glue-free, covalent room temperature bonding. This mold-free process does not require clean room equipment and therefore allows for rapid, i.e., less than one hour, design-fabricate-test cycles, using a material suited for larger-scale production. The excellent photolithographic properties of this new OSTE formulation allow patterning with unprecedented, for thiol-ene polymer systems, resolution in hundreds of micrometers thick layers, 200 μm thick in this work. Moreover, we demonstrated robust, covalent and spatially controlled modification of the microchannel surfaces with an initial contact angle of 76° by patterning hydrophobic/hydrophilic areas with contact angles of 102° and 43°, respectively.

Computer science, Informatique, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Informatique; automatique theorique; systemes, Computer science; control theory; systems, Informatique théorique, Theoretical computing, Automates. Machines abstraites. Machines de turing, Automata. Abstract machines. Turing machines, Logiciel, Software, Conception assistée, Computer aided design, Intelligence artificielle, Artificial intelligence, Reconnaissance des formes. Traitement numérique des images. Géométrie algorithmique, Pattern recognition. Digital image processing. Computational geometry, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Biotechnologie, Biotechnology, Méthodes. Procédés. Technologies, Methods. Procedures. Technologies, Cultures de cellules eucaryotes, Eukaryotic cell cultures, Cellules animales, Animal cells, Etablissement de nouvelles lignées, amélioration des méthodes de culture, cultures en masse, Establishment of new cell lines, improvement of cultural methods, mass cultures, Architecture système, System architecture, Arquitectura sistema, Automate cellulaire, Cellular automaton, Autómata celular, Conception assistée, Computer aided design, Concepción asistida, Confluence, Confluencia, Génie tissulaire, Tissue engineering, Ingeniería de tejidos, Image tridimensionnelle, Tridimensional image, Imagen tridimensional, Interface, Interfase, Marche aléatoire, Random walk, Marcha aleatoria, Modélisation, Modeling, Modelización, Résultat expérimental, Experimental result, Resultado experimental, Système paramètre variable, Time varying system, Sistema parámetro variable, Visualisation donnée, Data visualization, Visualización de datos, 3-D simulation model, Cellular automata, Time-varying data, Tissue growth, and Visualization

Data Visualization affords us the ability to explore the spatial and temporal domains of many time-varying phenomena. In this article, we describe our application of visualization to a three-dimensional simulation model for tissue growth. We review the different components of the model where cellular automata is used to model populations of cells that execute persistent random walks, collide, and proliferate until they reach confluence. We then describe the system architecture of the developed visualization tool, the employed rendering techniques, and the related prototyping interfaces. We also discuss some of the visualization results obtained thus far that are pertinent to enhancing the validity of the computational model. This visualization tool could be useful in facilitating the research of scientists by providing them with meaningful means to interpret and analyze simulation data and to compare them to experimental results. Our objective in this work is to develop computer-aided design solutions that support the simulation of tissue growth and its design exploration.