Development of synthetic simulators for endoscope-assisted repair of metopic and sagittal craniosynostosis

OBJECTIVEEndoscope-assisted repair of craniosynostosis is a safe and efficacious alternative to open techniques. However, this procedure is challenging to learn, and there is significant variation in both its execution and outcomes. Surgical simulators may allow trainees to learn and practice this procedure prior to operating on an actual patient. The purpose of this study was to develop a realistic, relatively inexpensive simulator for endoscope-assisted repair of metopic and sagittal craniosynostosis and to evaluate the models’ fidelity and teaching content.METHODSTwo separate, 3D-printed, plastic powder–based replica skulls exhibiting metopic (age 1 month) and sagittal (age 2 months) craniosynostosis were developed. These models were made into consumable skull “cartridges” that insert into a reusable base resembling an infant’s head. Each cartridge consists of a multilayer scalp (skin, subcutaneous fat, galea, and periosteum); cranial bones with accurate landmarks; and the dura mater. Data related to model construction, use, and cost were collected. Eleven novice surgeons (residents), 9 experienced surgeons (fellows), and 5 expert surgeons (attendings) performed a simulated metopic and sagittal craniosynostosis repair using a neuroendoscope, high-speed drill, rongeurs, lighted retractors, and suction/irrigation. All participants completed a 13-item questionnaire (using 5-point Likert scales) to rate the realism and utility of the models for teaching endoscope-assisted strip suturectomy.RESULTSThe simulators are compact, robust, and relatively inexpensive. They can be rapidly reset for repeated use and contain a minimal amount of consumable material while providing a realistic simulation experience. More than 80% of participants agreed or strongly agreed that the models’ anatomical features, including surface anatomy, subgaleal and subperiosteal tissue planes, anterior fontanelle, and epidural spaces, were realistic and contained appropriate detail. More than 90% of participants indicated that handling the endoscope and the instruments was realistic, and also that the steps required to perform the procedure were representative of the steps required in real life.CONCLUSIONSBoth the metopic and sagittal craniosynostosis simulators were developed using low-cost methods and were successfully designed to be reusable. The simulators were found to realistically represent the surgical procedure and can be used to develop the technical skills required for performing an endoscope-assisted craniosynostosis repair.

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Rapid Antibody Selection Using Surface Plasmon Resonance for High-Speed and Sensitive Hazelnut Lateral Flow Prototypes

Biosensors ◽

10.3390/bios8040130 ◽

2018 ◽

Vol 8 (4) ◽

pp. 130 ◽

Cited By ~ 6

Author(s):

Georgina Ross ◽

Maria Bremer ◽

Jan Wichers ◽

Aart van Amerongen ◽

Michel Nielen

Keyword(s):

Surface Plasmon Resonance ◽

Surface Plasmon ◽

Plasmon Resonance ◽

High Speed ◽

Selection Process ◽

Low Cost ◽

Real Life ◽

Cross Reactivity ◽

Lateral Flow ◽

Label Free

Lateral Flow Immunoassays (LFIAs) allow for rapid, low-cost, screening of many biomolecules such as food allergens. Despite being classified as rapid tests, many LFIAs take 10–20 min to complete. For a really high-speed LFIA, it is necessary to assess antibody association kinetics. By using a label-free optical technique such as Surface Plasmon Resonance (SPR), it is possible to screen crude monoclonal antibody (mAb) preparations for their association rates against a target. Herein, we describe an SPR-based method for screening and selecting crude anti-hazelnut antibodies based on their relative association rates, cross reactivity and sandwich pairing capabilities, for subsequent application in a rapid ligand binding assay. Thanks to the SPR selection process, only the fast mAb (F-50-6B12) and the slow (S-50-5H9) mAb needed purification for labelling with carbon nanoparticles to exploit high-speed LFIA prototypes. The kinetics observed in SPR were reflected in LFIA, with the test line appearing within 30 s, almost two times faster when F-50-6B12 was used, compared with S-50-5H9. Additionally, the LFIAs have demonstrated their future applicability to real life samples by detecting hazelnut in the sub-ppm range in a cookie matrix. Finally, these LFIAs not only provide a qualitative result when read visually, but also generate semi-quantitative data when exploiting freely downloadable smartphone apps.

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3D Printed Fully Recycled TiO2-Polystyrene Nanocomposite Photocatalysts for Use against Drug Residues

Nanomaterials ◽

10.3390/nano10112144 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2144

Author(s):

Maria Sevastaki ◽

Mirela Petruta Suchea ◽

George Kenanakis

Keyword(s):

Tio2 Nanoparticles ◽

Large Scale ◽

Fused Deposition Modeling ◽

Low Cost ◽

Real Life ◽

3D Printer ◽

Alternative Route ◽

Fused Deposition ◽

Deposition Modeling ◽

3D Printed

In the present work, the use of nanocomposite polymeric filaments based on 100% recycled solid polystyrene everyday products, enriched with TiO2 nanoparticles with mass concentrations up to 40% w/w, and the production of 3D photocatalytic structures using a typical fused deposition modeling (FDM)-type 3D printer are reported. We provide evidence that the fabricated 3D structures offer promising photocatalytic properties, indicating that the proposed technique is indeed a novel low-cost alternative route for fabricating large-scale photocatalysts, suitable for practical real-life applications.

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Photocatalytic Properties of Eco-Friendly ZnO Nanostructures on 3D-Printed Polylactic Acid Scaffolds

Nanomaterials ◽

10.3390/nano11010168 ◽

2021 ◽

Vol 11 (1) ◽

pp. 168

Author(s):

Maria Sevastaki ◽

Vassilis M. Papadakis ◽

Cosmin Romanitan ◽

Mirela Petruta Suchea ◽

George Kenanakis

Keyword(s):

Polylactic Acid ◽

Large Scale ◽

Low Cost ◽

Three Dimensional ◽

Real Life ◽

Ammonium Bicarbonate ◽

Research Report ◽

Zno Nanostructures ◽

Pure Ethanol ◽

3D Printed

The present paper reports a novel approach for fabrication of eco-friendly ZnO nanoparticles onto three-dimensional (3D)-printed polylactic acid (PLA) scaffolds/structures. Several alcohol-based traditional Greek liquors were used to achieve the corrosion of metallic zinc collected from a typical galvanic anode to obtain photocatalytic active nanostructured ZnO, varying from water, to Greek “ouzo” and “raki”, and pure ethanol, in combination with “Baker’s ammonia” (ammonium bicarbonate), sold worldwide in every food store. The photocatalytic active ZnO nanostructures onto three-dimensional (3D)-printed PLA scaffolds were used to achieve the degradation of 50 ppm paracetamol in water, under UV irradiation. This study provides evidence that following the proposed low-cost, eco-friendly routes for the fabrication of large-scale photocatalysts, an almost 95% degradation of 50 ppm paracetamol in water can be achieved, making the obtained 3D ZnO/PLA structures excellent candidates for real life environmental applications. This is the first literature research report on a successful attempt of using this approach for the engineering of low-cost photocatalytic active elements for pharmaceutical contaminants in waters.

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Simulated and Experimental Investigation of Mechanical Properties for Improving Isotropic Fracture Strength of 3D-Printed Capsules

Materials ◽

10.3390/ma14164677 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4677

Author(s):

Taeuk Lim ◽

Hao Cheng ◽

Wonil Song ◽

Jasung Lee ◽

Sunghoon Kim ◽

...

Keyword(s):

Mechanical Properties ◽

Fracture Strength ◽

High Speed ◽

Applied Load ◽

Low Cost ◽

Powder Layer ◽

Strength Analysis ◽

Self Healing ◽

Compression Tests ◽

3D Printed

Three-dimensional (3D) printer-based self-healing capsules, embedded in cement composites, were proposed to heal cracks, as they allow for various structural designs of capsules, repeatable fabrication, and strength analysis. Out of many 3D printing methods, such as fusion deposition modeling (FDM), powder layer fusion, and PolyJet printing, FDM was used to design, analyze, and produce new self-healing capsules, which are widely used due to their high-speed, low-cost, and precise manufacturing. However, the PLA extruded in the FDM had low adhesion energy between stacked layers, which caused a degradation of the performance of the self-healing capsule, because it had different strengths depending on the angle between the stacked layers and the applied load within the concrete structure. Therefore, in this paper, specimens were produced, in accordance with ASTM specifications, using the FDM PLA method, and mechanical properties were obtained through tensile, shear, and compression tests. Additionally, the isotropic fracture characteristics of the four types of capsules were analyzed through finite element method analysis. Subsequently, the 3D-printed capsules were produced, and the fracture strength was analyzed in the x, y and z directions of the applied load through a compression test. As a result, the newly proposed capsule design was verified to have an isotropic fracture strength value of 1400% in all directions compared to conventional spherical thin film capsules

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Modal Parameter Extraction of a Turboset From High Speed Balance Data

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2938275 ◽

2008 ◽

Vol 130 (5) ◽

Author(s):

Anoop K. Dhingra ◽

Juan I. Hidalgo

Keyword(s):

Present Method ◽

High Speed ◽

Low Cost ◽

Real Life ◽

Structural Models ◽

Parameter Extraction ◽

Model Complexity ◽

Modal Parameter ◽

Industrial Setting ◽

Flexible Foundations

Turbosets used in power generation industry are frequently placed on flexible foundations, which significantly influence the overall dynamics. Establishment of structural models that capture the rotor and foundation effects reliably using finite element modeling or modal analysis is difficult because of model complexity and/or costs involved. This paper presents a method to extract modal parameter information of a turboset using frequency response function data recorded during high speed balancing. The main advantage of the present method over the others is the low cost and small effort involved, so that it is of practical use in an industrial setting. A real life example dealing with parameter extraction for a large generator rotor is presented to demonstrate its implementation.

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The Strategic Alliance between Clinical and Molecular Science in the War against SARS-CoV-2, with the Rapid-Diagnostics Test as an Indispensable Weapon for Front Line Doctors

International Journal of Molecular Sciences ◽

10.3390/ijms21124446 ◽

2020 ◽

Vol 21 (12) ◽

pp. 4446

Author(s):

Antonio Vittorino Gaddi ◽

Fabio Capello ◽

Leonardo Aluigi ◽

Pier Luigi Antignani ◽

Annapaola Callegaro ◽

...

Keyword(s):

High Speed ◽

Strategic Alliance ◽

Point Of Care ◽

Low Cost ◽

Real Life ◽

Diagnostic Purpose ◽

Rapid Diagnostics ◽

Immunochromatographic Strip ◽

Actual Problem ◽

Point Of Care Test

Our work concerns the actual problem of spread of SARS- CoV-2 outbreak which requires fast and correct as possible answer. In current scenario, the need of rapid answer put away the imperative of proper methodology. We focus on the serogical immunoassay for diagnosis of Covid-19 as an important weapon not only for diagnostic purpose, but also for epidemiologic one. The right equilibrium between high speed, low cost and accuracy is obtained with easy-to-use decentralized point-of-care test as the colloidal gold-based immunochromatographic strip assay which detects IgM and IgG antibodies directed against SARS-CoV-2. As our aim is to evaluate the efficacy of Covid-19 rapid tests and of serological assays in real-life settings, we designed a research protocol aimed to establish how to use correctly these diagnostics, taking into account the different possible clinical and epidemiological scenarios.

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Rapid Tooling for Impulse Forming

10.25518/esaform21.2483 ◽

2021 ◽

Author(s):

Lasse Langstädtler ◽

Alex Peer Intemann ◽

Marius Herrmann ◽

Christian Schenck ◽

Holger Pegel ◽

...

Keyword(s):

High Speed ◽

Layer Structure ◽

Low Cost ◽

Sheet Thickness ◽

Sheet Metals ◽

Copper Sheet ◽

High Speed Forming ◽

Scope Of Application ◽

3D Printed ◽

Cutting Processes

Compared to cutting processes such as milling, forming processes like electrohydraulic forming offer advantages regarding resource as well as energy efficiency. Due to high tooling costs, forming technologies are nonetheless considered as economically inefficient for low production quantities. Using a combination of high-speed forming with 3D printing technologies for tool manufacturing, three variants to reduce tooling time and costs for processing sheet metals for small quantities were proposed. Since the dies have to withstand high dynamic loads, 3D-printed low-cost dies made of polylactide (PLA) are limited regarding their form stability, mainly depending on the forming energy and sheet thickness. To enlarge the scope of application for 3D-printed dies a method to reinforce these dies is presented and investigated. Armoring of the dies was achieved by electrohydraulic cladding of the dies with 0.5 mm thick aluminum sheet metals. To characterize and compare the properties of the unarmored and the armored polylactide dies, specific characteristics of the formed sheet metals concerning the die wear and the molding quality were investigated. Polylactide dies enabled embossing of fine structures in addition to the forming of the die shape. Armoring of the dies led to a reduction of the embossed layer structure. Therefore, the armoring can be used as a way to control the characteristics of the formed sheet metals. In a further step, the cladding sheets were produced with copper sheet metals and used as sinking electrode for electric discharge machining of steel dies.

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Development and production experience of the multilayer curtain-coated linerboard of Ji’an PM No. 3,

TAPPI Journal ◽

10.32964/tj13.2.17 ◽

2014 ◽

Vol 13 (2) ◽

pp. 17-25

Author(s):

JUNMING SHU ◽

ARTHAS YANG ◽

PEKKA SALMINEN ◽

HENRI VAITTINEN

Keyword(s):

Titanium Dioxide ◽

High Speed ◽

Food Packaging ◽

Production Efficiency ◽

Positive Impact ◽

Low Cost ◽

Board Structure ◽

Flexographic Printing ◽

Curtain Coating ◽

Coating Formulations

The Ji’an PM No. 3 is the first linerboard machine in China to use multilayer curtain coating technology. Since successful startup at the end of 2011, further development has been carried out to optimize running conditions, coating formulations, and the base paper to provide a product with satisfactory quality and lower cost to manufacture. The key challenges include designing the base board structure for the desired mechanical strength, designing the surface properties for subsequent coating operations, optimizing the high-speed running of the curtain coater to enhance production efficiency, minimizing the amount of titanium dioxide in the coating color, and balancing the coated board properties to make them suitable for both offset and flexographic printing. The pilot and mill scale results show that curtain coating has a major positive impact on brightness, while smoothness is improved mainly by the blade coating and calendering conditions. Optimization of base board properties and the blade + curtain + blade concept has resulted in the successful use of 100% recycled fiber to produce base board. The optical, mechanical, and printability properties of the final coated board meet market requirements for both offset and flexographic printing. Machine runnability is excellent at the current speed of 1000 m/min, and titanium dioxide has been eliminated in the coating formulations without affecting the coating coverage. A significant improvement in the total cost of coated white liner production has been achieved, compared to the conventional concept of using virgin fiber in the top ply. Future development will focus on combining low cost with further quality improvements to make linerboard suitable for a wider range of end-use applications, including frozen-food packaging and folding boxboard.

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