Search results for "printing"
showing 10 items of 532 documents
Paternal uniparental disomy chromosome 14-like syndrome due a maternal de novo 160 kb deletion at the 14q32.2 region not encompassing the IG- and the…
2015
The human chromosome 14q32 carries a cluster of imprinted genes which include the paternally expressed genes (PEGs) DLK1 and RTL1, as well as the maternally expressed genes (MEGs) MEG3, RTL1as, and MEG8. PEGs and MEGs expression at the 14q32.2-imprinted region are regulated by two differentially methylated regions (DMRs): the IG-DMR and the MEG3-DMR, which are respectively methylated on the paternal and unmethylated on the maternal chromosome 14 in most cells. Genetic and epigenetic abnormalities affecting these imprinted gene clusters result in two different phenotypes currently known as maternal upd(14) syndrome and paternal upd(14) syndrome. However, only few patients carrying a maternal…
The application of 3d printing in plastic and reconstructive surgery: Case-control study in facial reconstruction
2017
The aim of this study was to explore the efficiency and usefulness of tridimensional printing in plastic and reconstructive surgery for lesions of the maxillofacial region. This was comparison study between two groups of patients. Six patients underwent surgical reconstruction, using a threedimensional model built on the basis of CT scans (group 1); and six patients underwent surgical reconstruction, without the use of a three-dimensional model (group 2). The following variables were evaluated: age, gender, histological diagnosis, cancer location, size of bone lesion, type of reconstruction, complications and surgical timing. A statistically significant difference was found in microsurgical…
3D printeru apkalpojošā personāla ķīmiskie un fizikālie darba vides riski
2018
“3D drukāšanas iekārtu apkalpojošā personāla ķīmiskie un fizikālie darba vides riski”. Darba autore: Anete Bušmane. Zinātniskā vadītāja: Dr.chem. Elīna Pajuste. Darba apjoms ir 64 lpp., tajās ietvertas 9 tabulas, 26 attēli, 1 pielikums un 42 literatūras avoti. 3D drukas nozarē no digitāla formāta tiek izdrukāts reāls un aptaustāms objekts, šī nozare līdz šim maz izpētīta ne tikai Latvijā, bet visā pasaulē. Galvenie faktori uz kuriem tiek vērsta uzmanība zinātniskajos rakstos un pētījumos, ir par nozarē sastopamajiem ķīmiskajiem un fizikālajiem riska faktoriem. Zinātnisko pētījumu šajā jomā nav daudz, un tie kas šobrīd ir pieejami nav ar viennozīmīgu informāciju, Latvijā šī nozare līdz šim n…
Green Composites Based on PLA and Agricultural or Marine Waste Prepared by FDM
2021
Three dimensional-printability of green composites is recently growing in importance and interest, especially in the view of feasibility to valorize agricultural and marine waste to attain green fillers capable of reducing bioplastic costs, without compromising their processability and performance from an environmental and mechanical standpoint. In this work, two lignocellulosic fillers, obtained from Opuntia ficus indica and Posidonia oceanica, were added to PLA and processed by FDM. Among the 3D printed biocomposites investigated, slight differences could be found in terms of PLA molecular weight and filler aspect ratio. It was shown that it is possible to replace up to 20% of bioplastic …
Microstructural characterization of a 3D-printed soil
2022
Transversal applications of 3D-printing (or Additive Manufacturing) have been recently implemented in the field of Geomechanics. In a 3D-printing process, the printed volume is obtained from successive layering of adjacent soil filaments. In this work, the fabric of an as-printed soil has been carried out by combining Mercury Intrusion Porosimetry (MIP) tests and Scanning Electron Microscope (SEM) observations, with the aim to highlight how the particle arrangements and the orientation and shape of pores are linked to the printing operation. The microstructural analyses showed that macropores are the result of the relative position of the filaments and their initial distortion in quasi-undr…
Design challenges and opportunities of 3D printing
2019
In the future, the number and complexity of products made using additive manufacturing (AM) techniques will increase rapidly. The development of softwares and algorithms related to processes will eliminate extra intermediate steps between the product design and the end product, and will finally give us more intelligent way to manufacture these new products. More efficient 3D printing processes will enable the production of cheaper individual items and, furthermore, they will increase the demand for these high - quality tailored unrivalled solutions. The market potential is huge. However, at present the fundamentals of the area are only lightly studied and several key challenges concerning s…
The emerging role of 3D printing in the fabrication of detection systems
2021
Abstract 3D printing is fast evolving as an additive manufacturing technique that has been adopted in (bio)analytical science because of the ample variety of materials and technologies currently available for highly affordable prototyping. This review focuses on the unique characteristics of 3D printing for manufacturing of optical and electrochemical detection systems, and sampling interfaces for analytical purposes using fused deposition modelling, vat polymerization (stereolithography and digital light processing) and photopolymer inkjet printing. The majority of works surveyed within the time span of mid-2018 to mid-2020 encompassed the fabrication of several components of the detection…
Porous 3D Printed Scavenger Filters for Selective Recovery of Precious Metals from Electronic Waste
2018
Selective laser sintering (SLS) 3D printing is used to fabricate highly macroporous ion scavenger filters for recovery of Pd and Pt from electronic waste. The scavengers are printed by using a mixture of polypropylene with 10 wt% of type‐1 anion exchange resin. Porosities and the flow‐through properties of the filters are controlled by adjusting the SLS printing parameters. The cylinder‐shaped filters are used in selective recovery of Pd and Pt from acidic leachate of electronic waste simply by passing the solution through the object. Under such conditions, the scavenger filters are able to capture Pd and Pt as anionic complexes with high efficiency from a solution containing mixture of dif…
Quality Control in 3D Printing: Accuracy Analysis of 3D-Printed Models of Patient-Specific Anatomy
2021
As comparative data on the precision of 3D-printed anatomical models are sparse, the aim of this study was to evaluate the accuracy of 3D-printed models of vascular anatomy generated by two commonly used printing technologies. Thirty-five 3D models of large (aortic, wall thickness of 2 mm, n = 30) and small (coronary, wall thickness of 1.25 mm, n = 5) vessels printed with fused deposition modeling (FDM) (rigid, n = 20) and PolyJet (flexible, n = 15) technology were subjected to high-resolution CT scans. From the resulting DICOM (Digital Imaging and Communications in Medicine) dataset, an STL file was generated and wall thickness as well as surface congruency were compared with the original …
3D Printed Palladium Catalyst for Suzuki-Miyaura Cross-coupling Reactions
2020
Selective laser sintering (SLS) 3d printing was utilized to manufacture a solid catalyst for Suzuki-Miyaura cross-coupling reactions from polypropylene as a base material and palladium nanoparticles on silica (SilicaCat Pd(0)R815-100 by SiliCycle) as the catalytically active additive. The 3d printed catalyst showed similar activity to that of the pristine powdery commercial catalyst, but with improved practical recoverability and reduced leaching of palladium into solution. Recycling of the printed catalyst led to increase of the induction period of the reactions, attributed to the pseudo-homogeneous catalysis. The reaction is initiated by oxidative addition of aryl iodide to palladium nano…