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Grine FE, Mongle CS, Kollmer W, Romanos G, du Plessis A, Maureille B, Braga J. Hypercementosis in Late Pleistocene Homo sapiens fossils from Klasies River Main Site, South Africa. Arch Oral Biol 2023; 149:105664. [PMID: 36889227 DOI: 10.1016/j.archoralbio.2023.105664] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 02/23/2023] [Accepted: 02/26/2023] [Indexed: 03/06/2023]
Abstract
OBJECTIVE To examine early Homo sapiens fossils from the Late Pleistocene site of Klasies River Main Site, South Africa for evidence of hypercementosis. The specimens represent seven adult individuals dated to between 119,000 and 58,000 years ago. These observations are contextualized in relation to the incidences of hypercementosis among recent human populations and fossil human samples and the potential etiologies of hypercementosis. DESIGN The fossils were investigated utilizing micro-CT and nano-CT scanning to visualize and measure cementum apposition on permanent incisor, premolar and molar roots. Cementum thickness was measured at mid-root level, and the volume of the cementum sleeve was calculated for the two fossil specimens that display marked hypercementosis. RESULTS Two of the fossils display no evidence of cementum hypertrophy. Three exhibit moderate cementum thickening, barely attaining the quantitative threshold for hypercementosis. Two evince marked hypercementosis. One of the Klasies specimens with marked hypercementosis is judged to be an older individual with periapical abscessing. The second specimen is a younger adult, and seemingly similar in age to other Klasies fossils that exhibit only minimal cementum apposition. However, this second specimen exhibits dento-alveolar ankylosis of the premolar and molars. CONCLUSIONS These two fossils from Klasies River Main Site provide the earliest manifestation of hypercementosis in Homo sapiens.
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Affiliation(s)
- Frederick E Grine
- Department of Anthropology, Stony Brook University, Stony Brook, NY 11794, USA; Department of Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794, USA.
| | - Carrie S Mongle
- Department of Anthropology, Stony Brook University, Stony Brook, NY 11794, USA; Turkana Basin Institute, Stony Brook University, Stony Brook, NY 11794, USA
| | - William Kollmer
- Department of Anthropology, Stony Brook University, Stony Brook, NY 11794, USA; Department of Periodontology, Stony Brook University School of Dental Medicine, Stony Brook, NY 11794, USA
| | - Georgios Romanos
- Department of Periodontology, Stony Brook University School of Dental Medicine, Stony Brook, NY 11794, USA
| | - Anton du Plessis
- Department of Physics, Stellenbosch University, Stellenbosch 7602, South Africa; Object Research Systems, 460 Saint-Catherine St. W, Montreal, Quebec H3B 1A7, Canada
| | - Bruno Maureille
- Université de Bordeaux, CNRS, Ministère de la Culture, PACEA, UMR5199, F-33600 Pessac, France
| | - José Braga
- Center for Anthrobiology & Genomics Institute of Toulouse, CNRS UMR 5288, Université de Toulouse, Université Paul Sabatier, 37 allées Jules Guesde, Toulouse 31000, France
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Emanuelli L, De Biasi R, Fu H, du Plessis A, Lora C, Jam A, Benedetti M, Pellizzari M. Metrological characterization of porosity graded β-Ti21S triply periodic minimal surface cellular structure manufactured by laser powder bed fusion. Int J Bioprint 2023; 9:729. [PMID: 37334037 PMCID: PMC10272211 DOI: 10.18063/ijb.729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 02/28/2023] [Indexed: 06/20/2023] Open
Abstract
The design of a functionally graded porous structure (FGPS) for use in prosthetic devices is crucial for meeting both mechanical and biological requirements. One of the most commonly used cellular structures in FGPS is the triply periodic minimal surface (TPMS) structure due to its ability to be defined by implicit equations, which allows for smooth transitions between layers. This study evaluates the feasibility of using a novel β-Ti21S alloy to fabricate TPMS-based FGPS. This beta titanium alloy exhibits low elastic modulus (53 GPa) and good mechanical properties in as-built condition. Two TPMS FGPSs with relative density gradients of 0.17, 0.34, 0.50, 0.66, and 0.83 and unit cell sizes of 2.5 mm and 4 mm were designed and fabricated using laser powder bed fusion (LPBF). The as-manufactured structures were analyzed using scanning electron microscopy (SEM) and X-ray micro-computed tomography (μ-CT), and the results were compared to the design. The analysis revealed that the pore size and ligament thickness were undersized by less than 5%. Compression tests showed that the stabilized elastic modulus was 4.1 GPa for the TPMS with a 2.5 mm unit cell size and 10.7 GPa for the TPMS with a 4 mm unit cell size. A finite element simulation was performed to predict the specimen's elastic properties, and a lumped model based on lattice homogenized properties was proposed and its limitations were explored.
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Affiliation(s)
- Lorena Emanuelli
- INSTM (Operative center: University of Trento), Trento, 38123, Italy
| | - Raffaele De Biasi
- Department of Industrial Engineering, University of Trento, Trento, Italy
| | - Huijuan Fu
- INSTM (Operative center: University of Trento), Trento, 38123, Italy
| | - Anton du Plessis
- Research Group 3D Innovation, Stellenbosch University, Stellenbosch, South Africa
- Object Research Systems, Montreal, Canada
| | - Carlo Lora
- SISMA SpA, Piovene Rocchette, Vicenza, Italy
| | - Alireza Jam
- Department of Industrial Engineering, University of Trento, Trento, Italy
| | - Matteo Benedetti
- Department of Industrial Engineering, University of Trento, Trento, Italy
| | - Massimo Pellizzari
- Department of Industrial Engineering, University of Trento, Trento, Italy
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Emanuelli L, Jam A, du Plessis A, Lora C, Biasi RD, Benedetti M, Pellizzari M. Manufacturability of functionally graded porous β-Ti21S auxetic architected biomaterials produced by laser powder bed fusion: Comparison between 2D and 3D metrological characterization. Int J Bioprint 2023; 9:728. [PMID: 37323506 PMCID: PMC10261167 DOI: 10.18063/ijb.728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023] Open
Abstract
Functionally graded porous structures (FGPSs) are attracting increasing interest in the manufacture of prostheses that benefit from lower stiffness and optimized pore size for osseointegration. In this work, we explore the possibility of employing FGPSs with auxetic unit cells. Their negative Poisson's ratio was exploited to reduce the loss of connection between prosthesis and bone usually occurring in standard implant loaded under tension and therefore undergoing lateral shrinking. In addition, to further improve osseointegration and mitigate stress shielding effects, auxetic FGPSs were fabricated in this work using a novel β-Ti21S alloy characterized by a lower Young's modulus compared to traditional α + β Ti alloys. Specifically, two different auxetic FGPSs with aspect ratio equal to 1.5 and angle θ of 15° and 25° with a relative density (ρr) gradient of 0.34, 0.49, 0.66 and of 0.40, 0.58, 0.75 were designed and printed by laser powder bed fusion. The 2D and 3D metrological characterization of the as-manufactured structures was compared with the design. 2D metrological characterization was carried out using scanning electron microscopy analysis, while for the 3D characterization, X-ray micro-CT imaging was used. An undersizing of the pore size and strut thickness in the as-manufactured sample was observed in both auxetic FGPSs. A maximum difference in the strut thickness of -14 and -22% was obtained in the auxetic structure with θ = 15° and 25°, respectively. On the contrary, a pore undersizing of -19% and -15% was evaluated in auxetic FGPS with θ = 15° and 25°, respectively. Compression mechanical tests allowed to determine stabilized elastic modulus of around 4 GPa for both FGPSs. Homogenization method and analytical equation were used and the comparison with experimental data highlights a good agreement of around 4% and 24% for θ = 15° and 25°, respectively.
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Affiliation(s)
- Lorena Emanuelli
- INSTM (Operative center: University of Trento), Via Sommarive 9, Trento, Italy
| | - Alireza Jam
- University of Trento, Department of Industrial Engineering, Trento, Italy
| | - Anton du Plessis
- Research Group 3D Innovation, Stellenbosch University, Stellenbosch, South Africa
- Object Research Systems, Montreal, Canada
| | - Carlo Lora
- SISMA SpA, Piovene Rocchette, Vicenza, Italy
| | - Raffaele De Biasi
- University of Trento, Department of Industrial Engineering, Trento, Italy
| | - Matteo Benedetti
- University of Trento, Department of Industrial Engineering, Trento, Italy
| | - Massimo Pellizzari
- University of Trento, Department of Industrial Engineering, Trento, Italy
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Evans LM, Sözümert E, Keenan BE, Wood CE, du Plessis A. A Review of Image-Based Simulation Applications in High-Value Manufacturing. Arch Comput Methods Eng 2023; 30:1495-1552. [PMID: 36685137 PMCID: PMC9847465 DOI: 10.1007/s11831-022-09836-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 10/15/2022] [Indexed: 06/17/2023]
Abstract
Image-Based Simulation (IBSim) is the process by which a digital representation of a real geometry is generated from image data for the purpose of performing a simulation with greater accuracy than with idealised Computer Aided Design (CAD) based simulations. Whilst IBSim originates in the biomedical field, the wider adoption of imaging for non-destructive testing and evaluation (NDT/NDE) within the High-Value Manufacturing (HVM) sector has allowed wider use of IBSim in recent years. IBSim is invaluable in scenarios where there exists a non-negligible variation between the 'as designed' and 'as manufactured' state of parts. It has also been used for characterisation of geometries too complex to accurately draw with CAD. IBSim simulations are unique to the geometry being imaged, therefore it is possible to perform part-specific virtual testing within batches of manufactured parts. This novel review presents the applications of IBSim within HVM, whereby HVM is the value provided by a manufactured part (or conversely the potential cost should the part fail) rather than the actual cost of manufacturing the part itself. Examples include fibre and aggregate composite materials, additive manufacturing, foams, and interface bonding such as welding. This review is divided into the following sections: Material Characterisation; Characterisation of Manufacturing Techniques; Impact of Deviations from Idealised Design Geometry on Product Design and Performance; Customisation and Personalisation of Products; IBSim in Biomimicry. Finally, conclusions are drawn, and observations made on future trends based on the current state of the literature.
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Affiliation(s)
- Llion Marc Evans
- Faculty of Science and Engineering, Swansea University, Swansea, SA1 8EN UK
- United Kingdom Atomic Energy Authority, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB UK
| | - Emrah Sözümert
- Faculty of Science and Engineering, Swansea University, Swansea, SA1 8EN UK
| | - Bethany E. Keenan
- Cardiff School of Engineering, Cardiff University, Cardiff, CF24 3AA UK
| | - Charles E. Wood
- School of Mechanical & Design Engineering, University of Portsmouth, Portsmouth, PO1 3DJ UK
| | - Anton du Plessis
- Object Research Systems, Montreal, H3B 1A7 Canada
- Research Group 3DInnovation, Stellenbosch University, Stellenbosch, 7602 South Africa
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5
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Wells G, Glasgow JN, Nargan K, Lumamba K, Madansein R, Maharaj K, Perumal LY, Matthew M, Hunter RL, Pacl H, Peabody Lever JE, Stanford DD, Singh SP, Bajpai P, Manne U, Benson PV, Rowe SM, le Roux S, Sigal A, Tshibalanganda M, Wells C, du Plessis A, Msimang M, Naidoo T, Steyn AJC. A high-resolution 3D atlas of the spectrum of tuberculous and COVID-19 lung lesions. EMBO Mol Med 2022; 14:e16283. [PMID: 36285507 PMCID: PMC9641421 DOI: 10.15252/emmm.202216283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 09/26/2022] [Accepted: 09/27/2022] [Indexed: 02/01/2023] Open
Abstract
Our current understanding of the spectrum of TB and COVID-19 lesions in the human lung is limited by a reliance on low-resolution imaging platforms that cannot provide accurate 3D representations of lesion types within the context of the whole lung. To characterize TB and COVID-19 lesions in 3D, we applied micro/nanocomputed tomography to surgically resected, postmortem, and paraffin-embedded human lung tissue. We define a spectrum of TB pathologies, including cavitary lesions, calcium deposits outside and inside necrotic granulomas and mycetomas, and vascular rearrangement. We identified an unusual spatial arrangement of vasculature within an entire COVID-19 lobe, and 3D segmentation of blood vessels revealed microangiopathy associated with hemorrhage. Notably, segmentation of pathological anomalies reveals hidden pathological structures that might otherwise be disregarded, demonstrating a powerful method to visualize pathologies in 3D in TB lung tissue and whole COVID-19 lobes. These findings provide unexpected new insight into the spatial organization of the spectrum of TB and COVID-19 lesions within the framework of the entire lung.
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Affiliation(s)
- Gordon Wells
- Africa Health Research InstituteUniversity of KwaZulu‐NatalDurbanSouth Africa
| | - Joel N Glasgow
- Department of MicrobiologyUniversity of Alabama at BirminghamBirminghamALUSA
| | - Kievershen Nargan
- Africa Health Research InstituteUniversity of KwaZulu‐NatalDurbanSouth Africa
| | - Kapongo Lumamba
- Africa Health Research InstituteUniversity of KwaZulu‐NatalDurbanSouth Africa
| | - Rajhmun Madansein
- Inkosi Albert Luthuli Central Hospital and University of KwaZulu‐NatalDurbanSouth Africa
| | - Kameel Maharaj
- Inkosi Albert Luthuli Central Hospital and University of KwaZulu‐NatalDurbanSouth Africa
| | - Leon Y Perumal
- Perumal & Partners RadiologistsAhmed Al‐Kadi Private HospitalDurbanSouth Africa
| | - Malcolm Matthew
- Perumal & Partners RadiologistsAhmed Al‐Kadi Private HospitalDurbanSouth Africa
| | - Robert L Hunter
- Department of Pathology and Laboratory MedicineUniversity of Texas Health Sciences Center at HoustonHoustonTXUSA
| | - Hayden Pacl
- Medical Scientist Training ProgramUniversity of Alabama at BirminghamBirminghamALUSA
| | | | - Denise D Stanford
- Department of MedicineUniversity of Alabama at BirminghamBirminghamALUSA
- Cystic Fibrosis Research CenterUniversity of Alabama at BirminghamBirminghamALUSA
| | - Satinder P Singh
- Department of MedicineUniversity of Alabama at BirminghamBirminghamALUSA
- Department of RadiologyUniversity of Alabama at BirminghamBirminghamALUSA
| | - Prachi Bajpai
- Department of PathologyUniversity of Alabama at BirminghamBirminghamALUSA
| | - Upender Manne
- Department of PathologyUniversity of Alabama at BirminghamBirminghamALUSA
| | - Paul V Benson
- Department of PathologyUniversity of Alabama at BirminghamBirminghamALUSA
| | - Steven M Rowe
- Department of MedicineUniversity of Alabama at BirminghamBirminghamALUSA
- Cystic Fibrosis Research CenterUniversity of Alabama at BirminghamBirminghamALUSA
| | | | - Alex Sigal
- Africa Health Research InstituteUniversity of KwaZulu‐NatalDurbanSouth Africa
| | - Muofhe Tshibalanganda
- Research Group 3D Innovation, Physics DepartmentStellenbosch UniversityStellenboschSouth Africa
| | - Carlyn Wells
- CT Scanner Facility, Central Analytical FacilitiesStellenbosch UniversityStellenboschSouth Africa
| | - Anton du Plessis
- Research Group 3D Innovation, Physics DepartmentStellenbosch UniversityStellenboschSouth Africa
- Object Research SystemsMontrealQCCanada
| | - Mpumelelo Msimang
- Department of Anatomical Pathology, National Health Laboratory ServiceInkosi Albert Luthuli Central HospitalDurbanSouth Africa
| | - Threnesan Naidoo
- Africa Health Research InstituteUniversity of KwaZulu‐NatalDurbanSouth Africa
- Department of Anatomical Pathology, National Health Laboratory ServiceInkosi Albert Luthuli Central HospitalDurbanSouth Africa
- Department of Laboratory Medicine & PathologyWalter Sisulu UniversityEastern CapeSouth Africa
| | - Adrie J C Steyn
- Africa Health Research InstituteUniversity of KwaZulu‐NatalDurbanSouth Africa
- Department of MicrobiologyUniversity of Alabama at BirminghamBirminghamALUSA
- Centers for AIDS Research and Free Radical BiologyUniversity of Alabama at BirminghamBirminghamALUSA
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6
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Balzeau A, Albessard-Ball L, Kubicka AM, Filippo A, Beaudet A, Santos E, Bienvenu T, Arsuaga JL, Bartsiokas A, Berger L, Bermúdez de Castro JM, Brunet M, Carlson KJ, Daura J, Gorgoulis VG, Grine FE, Harvati K, Hawks J, Herries A, Hublin JJ, Hui J, Ives R, Joordens JA, Kaifu Y, Kouloukoussa M, Léger B, Lordkipanidze D, Margvelashvili A, Martin J, Martinón-Torres M, May H, Mounier A, du Plessis A, Rae T, Röding C, Sanz M, Semal P, Stratford D, Stringer C, Tawane M, Temming H, Tsoukala E, Zilhão J, Zipfel B, Buck LT. Frontal sinuses and human evolution. Sci Adv 2022; 8:eabp9767. [PMID: 36269821 PMCID: PMC9586476 DOI: 10.1126/sciadv.abp9767] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 09/01/2022] [Indexed: 06/16/2023]
Abstract
The frontal sinuses are cavities inside the frontal bone located at the junction between the face and the cranial vault and close to the brain. Despite a long history of study, understanding of their origin and variation through evolution is limited. This work compares most hominin species' holotypes and other key individuals with extant hominids. It provides a unique and valuable perspective of the variation in sinuses position, shape, and dimensions based on a simple and reproducible methodology. We also observed a covariation between the size and shape of the sinuses and the underlying frontal lobes in hominin species from at least the appearance of Homo erectus. Our results additionally undermine hypotheses stating that hominin frontal sinuses were directly affected by biomechanical constraints resulting from either chewing or adaptation to climate. Last, we demonstrate their substantial potential for discussions of the evolutionary relationships between hominin species.
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Affiliation(s)
- Antoine Balzeau
- UMR 7194 Histoire Naturelle de l’Homme Préhistorique, CNRS, PaleoFED Team, Département Homme et Environnement, Muséum national d’Histoire naturelle, Paris, France
- Department of African Zoology, Royal Museum for Central Africa, Tervuren, Belgium
| | - Lou Albessard-Ball
- UMR 7194 Histoire Naturelle de l’Homme Préhistorique, CNRS, PaleoFED Team, Département Homme et Environnement, Muséum national d’Histoire naturelle, Paris, France
- PalaeoHub, Department of Archaeology, University of York, York, UK
| | - Anna Maria Kubicka
- UMR 7194 Histoire Naturelle de l’Homme Préhistorique, CNRS, PaleoFED Team, Département Homme et Environnement, Muséum national d’Histoire naturelle, Paris, France
- Department of Zoology, Poznań University of Life Sciences, Poznań, Poland
| | - Andréa Filippo
- UMR 7194 Histoire Naturelle de l’Homme Préhistorique, CNRS, PaleoFED Team, Département Homme et Environnement, Muséum national d’Histoire naturelle, Paris, France
| | - Amélie Beaudet
- Department of Archaeology, University of Cambridge, Cambridge, UK
- School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, Johannesburg, South Africa
- Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Elena Santos
- Centro Mixto UCM-ISCIII de Evolución y Comportamiento Humanos, Departamento de Paleontología, Facultad Ciencias Geológicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Cátedra de Otoacústica Evolutiva y Paleoantropología (HM Hospitales - Universidad de Alcalá), Departamento de Ciencias de la Vida, Universidad de Alcalá, Alcalá de Henares, Spain
- Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), Paseo de la Sierra de Atapuerca 3, 09002 Burgos, Spain
| | - Thibault Bienvenu
- Department of Anthropology and Anthropological Museum, University of Zurich, CH-8052 Zurich, Switzerland
| | - Juan-Luis Arsuaga
- Centro Mixto UCM-ISCIII de Evolución y Comportamiento Humanos, Departamento de Paleontología, Facultad Ciencias Geológicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Antonis Bartsiokas
- Department of History and Ethnology, Democritus University of Thrace, Komotini, Greece
| | - Lee Berger
- Centre for the Exploration of the Deep Human Journey, University of the Witwatersrand, WITS, Johannesburg 2050, South Africa
| | - José María Bermúdez de Castro
- Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), Paseo de la Sierra de Atapuerca 3, 09002 Burgos, Spain
- Anthropology Department, University College London, London, UK
| | - Michel Brunet
- Chaire de Paléoanthropologie Humaine, Collège de France, Paris, France
- UMR 7262 CNRS, Université de Poitiers, Poitiers, France
| | - Kristian J. Carlson
- Evolutionary Studies Institute, University of the Witwatersrand, Palaeosciences Centre, Wits, Johannesburg 2050, South Africa
- Department of Integrative Anatomical Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Joan Daura
- Departament d’Història i Arqueologia, Facultat de Geografia i Història, Universitat de Barcelona, c/Montalegre 6, 08001 Barcelona, Spain
- Centro de Arqueologia da Universidade de Lisboa (UNIARQ), Faculdade de Letras de Lisboa, Universidade de Lisboa, Alameda da Universidade, 1600-214 Lisboa, Portugal
| | - Vassilis G. Gorgoulis
- Department of Histology and Embryology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
- Biomedical Research Foundation of the Academy of Athens, Athens, Greece
- Ninewells Hospital and Medical School, University of Dundee, Dundee, UK
- Division of Cancer Sciences, School of Medical Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M20 4GJ, UK
| | - Frederick E. Grine
- Departments of Anthropology and Anatomical Sciences, Stony Brook University, Stony Brook, NY 11794, USA
| | - Katerina Harvati
- Senckenberg Center for Human Evolution and Paleoenvironment and Institute for Archaeological Sciences, Eberhard Karls Universität Tübingen, Rümelinstr. 23, 72070 Tübingen, Germany
| | - John Hawks
- University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Andy Herries
- Department of Archaeology and History, La Trobe University, Bundoora, VIC 3086, Australia
- Palaeo-Research Institute, University of Johannesburg, Gauteng, South Africa
| | - Jean-Jacques Hublin
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany
- Chaire de Paléoanthropologie, Collège de France, 75005 Paris, France
| | - Jiaming Hui
- UMR 7194 Histoire Naturelle de l’Homme Préhistorique, CNRS, PaleoFED Team, Département Homme et Environnement, Muséum national d’Histoire naturelle, Paris, France
| | - Rachel Ives
- Centre for Human Evolution Research, History Museum, London, UK
| | - Josephine A. Joordens
- Naturalis Biodiversity Center, Leiden, Netherlands
- Faculty of Science and Engineering, Maastricht University, Netherlands
| | - Yousuke Kaifu
- The University Museum, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Mirsini Kouloukoussa
- Museum of Anthropology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Baptiste Léger
- Columbia University, 116 Street & Broadway, New York, NY 10027, USA
| | - David Lordkipanidze
- Georgian National Museum, Purtseladze Str. 3, 0105 Tbilisi, Georgia
- Ivane Javakhishvili Tbilisi State University, Chavchavadze Av. 1, 0179 Tbilisi, Georgia
| | - Ann Margvelashvili
- Georgian National Museum, Purtseladze Str. 3, 0105 Tbilisi, Georgia
- Ivane Javakhishvili Tbilisi State University, Chavchavadze Av. 1, 0179 Tbilisi, Georgia
| | - Jesse Martin
- Palaeoscience, Department of Archaeology and History, La Trobe University, Bundoora, VIC 3086, Australia
| | - María Martinón-Torres
- Centro Nacional de Investigación sobre la Evolución Humana (CENIEH), Paseo de la Sierra de Atapuerca 3, 09002 Burgos, Spain
- Anthropology Department, University College London, London, UK
| | - Hila May
- Department of Anatomy and Anthropology, Sackler Faculty of Medicine, Tel Aviv University, Post Office Box 39040, Tel Aviv 6997801, Israel
- Shmunis Family Anthropology Institute, Dan David Center for Human Evolution and Biohistory Research, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Aurélien Mounier
- UMR 7194 Histoire Naturelle de l’Homme Préhistorique, CNRS, PaleoFED Team, Département Homme et Environnement, Muséum national d’Histoire naturelle, Paris, France
- Department of History and Ethnology, Democritus University of Thrace, Komotini, Greece
| | - Anton du Plessis
- Physics Department, Stellenbosch University, Stellenbosch, South Africa
| | - Todd Rae
- Centre for Research in Evolutionary Anthropology, Department of Life Sciences, Roehampton University, Holybourne Avenue, London SW15 4JD, UK
| | - Carolin Röding
- Paleoanthropology, Senckenberg Centre for Human Evolution and Palaeoenvironment, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Montserrat Sanz
- Centro de Arqueologia da Universidade de Lisboa (UNIARQ), Faculdade de Letras de Lisboa, Universidade de Lisboa, Alameda da Universidade, 1600-214 Lisboa, Portugal
- Grup de Recerca del Quaternari (GRQ-SERP), Departament d’Història i Arqueologia, Universitat de Barcelona, Carrer Montalegre, 6, 08001 Barcelona, Spain
| | - Patrick Semal
- Royal Belgian Institute of Natural Sciences, Brussels 1000, Belgium
| | - Dominic Stratford
- School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, WITS, Johannesburg 2050, South Africa
| | - Chris Stringer
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany
| | - Mirriam Tawane
- Ditsong National Museum of Natural History, Pretoria, South Africa
| | - Heiko Temming
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany
| | - Evangelia Tsoukala
- Laboratory of Geology and Palaeontology, School of Geology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - João Zilhão
- UNIARQ-Centro de Arqueologia da Universidade de Lisboa, Faculdade de Letras, Universidade de Lisboa, 1600-214 Lisbon, Portugal
- Catalan Institution for Research and Advanced Studies, 08010 Barcelona, Spain
- Department of History and Archaeology, University of Barcelona, 08007 Barcelona, Spain
| | - Bernhard Zipfel
- Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa
| | - Laura T. Buck
- Research Centre for Evolutionary Anthropology and Palaeoecology, School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, UK
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Shange M, Yadroitsava I, du Plessis A, Yadroitsev I. Roughness and Near-Surface Porosity of Unsupported Overhangs Produced by High-Speed Laser Powder Bed Fusion. 3D Print Addit Manuf 2022; 9:288-300. [PMID: 36660231 PMCID: PMC9831547 DOI: 10.1089/3dp.2020.0097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Laser powder bed fusion (LPBF) is a promising technology that requires further work to improve productivity to be adopted more widely. One possible approach is to increase the laser power and scan speed. A customized high-speed and high-power LPBF system has been developed for this purpose. The current study investigated the surface roughness and near-surface porosity as a result of unsupported overhangs at varying inclination angles and orientations during the manufacturing of Ti6Al4V parts with this custom high-speed and high-power LPBF system. It is known that surface roughness and porosity are among the main drawbacks for parts manufactured by LPBF, and that supports are required for overhang regions with low inclination angles relative to the powder bed, typically in commercial LPBF systems requiring supports for regions with inclination angles less than 45°. However, the appropriate inclination angles for this custom system with high power and speed requires investigation. In this article, a simple benchmark test artefact with different inclination angles was manufactured in different orientations on the build platform and characterized by X-ray tomography, touch probe roughness meter, optical microscopy, and scanning electron microscopy. The analysis of surface roughness and near-surface porosity at upskin and downskin regions was performed as a function of inclination angle. The results indicate that the high-speed LPBF process produces relatively high roughness in all cases, with different porosity distributions at upskin and downskin areas. Both roughness and porosity vary as a function of inclination angle. Significant warping was observed, depending on build orientation relative to laser scanning direction. These are the first reported results of the detailed surface roughness and porosity characterization of part quality from such a high-speed, high-power LPBF process.
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Affiliation(s)
- Mfanufikile Shange
- Laser Enabled Manufacturing, National Laser Centre, CSIR, Pretoria, South Africa
- Department of Mechanical and Mechatronic Engineering, Central University of Technology, Free State, Bloemfontein, South Africa
| | - Ina Yadroitsava
- Department of Mechanical and Mechatronic Engineering, Central University of Technology, Free State, Bloemfontein, South Africa
| | - Anton du Plessis
- Research Group 3D Innovation, Stellenbosch University, Stellenbosch, South Africa
- Department of Mechanical Engineering, Nelson Mandela University, Port Elizabeth, South Africa
| | - Igor Yadroitsev
- Department of Mechanical and Mechatronic Engineering, Central University of Technology, Free State, Bloemfontein, South Africa
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Broeckhoven C, du Plessis A. Osteoderms as calcium reservoirs: Insights from the lizard Ouroborus cataphractus. J Anat 2022; 241:635-640. [PMID: 35502528 DOI: 10.1111/joa.13683] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 04/13/2022] [Accepted: 04/13/2022] [Indexed: 11/27/2022] Open
Abstract
The functional significance of osteoderms-bony elements embedded in the dermis-remains a topic of much debate. Although many hypotheses have been put forward in the past, the idea that osteoderms can serve as calcium reservoirs has received little experimental attention thus far. In this study, we use micro-computed tomography to investigate inter- and intrasexual variation in osteoderm density in the viviparous lizard Ouroborus cataphractus and conduct histochemical analyses to unravel the potential mechanism involved in mineral resorption from the osteoderms. Our results show that females have denser, more compact osteoderms than males of similar body sizes, regardless of the season during which they were collected and their reproductive state. Furthermore, a histochemical study demonstrates the presence of mononucleated TRAP-positive cells in the vascular canals of the osteoderms. Based on the findings of this study, we suggest that the mineral storage hypothesis merits further attention as a candidate explanation for osteoderm evolution.
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Affiliation(s)
- Chris Broeckhoven
- Laboratory of Functional Morphology, University of Antwerp, Wilrijk, Belgium
| | - Anton du Plessis
- Object Research Systems, Montreal, Canada.,Research group 3D Innovation, Stellenbosch University, Stellenbosch, South Africa
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Liu J, Nguyen-Van V, Panda B, Fox K, du Plessis A, Tran P. Additive Manufacturing of Sustainable Construction Materials and Form-finding Structures: A Review on Recent Progresses. 3D Print Addit Manuf 2022; 9:12-34. [PMID: 36660135 PMCID: PMC9831535 DOI: 10.1089/3dp.2020.0331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Recently, there has been an increasing interest on the sustainability advantage of 3D concrete printing (3DCP), where the original cement-based mixtures used for printing could be replaced or incorporated with environmental-friendly materials. The development in digital modeling and design tools also creates a new realm of form-finding architecture for 3DCP, which is based on topological optimization of volumetric mass and physical performance. This review provides a perspective of using different green cementitious materials, applications of structural optimization, and modularization methods for realizing sustainable construction with additive manufacturing. The fresh and hardened mechanical properties of various sustainable materials for extrusion-based 3D printing are presented, followed by discussions on different topology optimization techniques. The current state of global research and industrial applications in 3DCP, along with the development of sustainable construction materials, is also summarized. Finally, research and practical gaps identified in this review lead to several recommendations on material developments, digital design tool's prospects for 3DCP to achieve the sustainability goal.
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Affiliation(s)
- Junli Liu
- Department of Civil & Infrastructure Engineering, RMIT University, Melbourne, Australia
| | - Vuong Nguyen-Van
- Department of Civil & Infrastructure Engineering, RMIT University, Melbourne, Australia
- CIRTech Institute, Ho Chi Minh City University of Technology (HUTECH), Ho Chi Minh City, Viet Nam
| | - Biranchi Panda
- Singapore Centre for 3D Printing, School of Mechanical & Aerospace Engineering, Nanyang Technological University, Singapore
- Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati, India
| | - Kate Fox
- Department of Electrical & Biomedical Engineering, RMIT University, Melbourne, Australia
| | - Anton du Plessis
- Research group 3DInnovation, Stellenbosch University, Stellenbosch, South Africa
- Department of Mechanical Engineering, Nelson Mandela University, Port Elizabeth, South Africa
| | - Phuong Tran
- Department of Civil & Infrastructure Engineering, RMIT University, Melbourne, Australia
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10
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Wells G, Glasgow JN, Nargan K, Lumamba K, Madansein R, Maharaj K, Hunter RL, Naidoo T, Coetzer L, le Roux S, du Plessis A, Steyn AJC. Micro-Computed Tomography Analysis of the Human Tuberculous Lung Reveals Remarkable Heterogeneity in Three-dimensional Granuloma Morphology. Am J Respir Crit Care Med 2021; 204:583-595. [PMID: 34015247 PMCID: PMC8491258 DOI: 10.1164/rccm.202101-0032oc] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 05/20/2021] [Indexed: 11/16/2022] Open
Abstract
Rationale: Our current understanding of tuberculosis (TB) pathophysiology is limited by a reliance on animal models, the paucity of human TB lung tissue, and traditional histopathological analysis, a destructive two-dimensional approach that provides limited spatial insight. Determining the three-dimensional (3D) structure of the necrotic granuloma, a characteristic feature of TB, will more accurately inform preventive TB strategies.Objectives: To ascertain the 3D shape of the human tuberculous granuloma and its spatial relationship with airways and vasculature within large lung tissues.Methods: We characterized the 3D microanatomical environment of human tuberculous lungs by using micro computed tomography, histopathology, and immunohistochemistry. By using 3D segmentation software, we accurately reconstructed TB granulomas, vasculature, and airways in three dimensions and confirmed our findings by using histopathology and immunohistochemistry.Measurements and Main Results: We observed marked heterogeneity in the morphology, volume, and number of TB granulomas in human lung sections. Unlike depictions of granulomas as simple spherical structures, human necrotic granulomas exhibit complex, cylindrical, branched morphologies that are connected to the airways and shaped by the bronchi. The use of 3D imaging of human TB lung sections provides unanticipated insight into the spatial organization of TB granulomas in relation to the airways and vasculature.Conclusions: Our findings highlight the likelihood that a single, structurally complex lesion could be mistakenly viewed as multiple independent lesions when evaluated in two dimensions. In addition, the lack of vascularization within obstructed bronchi establishes a paradigm for antimycobacterial drug tolerance. Lastly, our results suggest that bronchogenic spread of Mycobacterium tuberculosis reseeds the lung.
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Affiliation(s)
- Gordon Wells
- Africa Health Research Institute, University of KwaZulu-Natal, Durban, South Africa
| | | | - Kievershen Nargan
- Africa Health Research Institute, University of KwaZulu-Natal, Durban, South Africa
| | - Kapongo Lumamba
- Africa Health Research Institute, University of KwaZulu-Natal, Durban, South Africa
| | - Rajhmun Madansein
- Department of Cardiothoracic Surgery, Nelson Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
| | - Kameel Maharaj
- Department of Cardiothoracic Surgery, Nelson Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa
| | - Robert L. Hunter
- Department of Pathology and Laboratory Medicine, University of Texas Health Sciences Center at Houston, Houston, Texas
| | - Threnesan Naidoo
- Department of Anatomical Pathology, National Health Laboratory Service, Inkosi Albert Luthuli Central Hospital, Durban, South Africa; and
| | - Llelani Coetzer
- Computed Tomography Scanner Facility, Central Analytical Facilities, Stellenbosch University, Stellenbosch, South Africa
| | - Stephan le Roux
- Computed Tomography Scanner Facility, Central Analytical Facilities, Stellenbosch University, Stellenbosch, South Africa
| | - Anton du Plessis
- Computed Tomography Scanner Facility, Central Analytical Facilities, Stellenbosch University, Stellenbosch, South Africa
| | - Adrie J. C. Steyn
- Africa Health Research Institute, University of KwaZulu-Natal, Durban, South Africa
- Department of Microbiology and
- Centers for AIDS Research and Free Radical Biology, University of Alabama at Birmingham, Birmingham, Alabama
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11
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du Plessis A, Els J, le Roux S, Tshibalanganda M, Pretorius T. Data for 3D printing enlarged museum specimens for the visually impaired. GigaByte 2020; 2020:gigabyte3. [PMID: 36824598 PMCID: PMC9631959 DOI: 10.46471/gigabyte.3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 05/09/2020] [Indexed: 11/09/2022] Open
Abstract
Museums are embracing new technologies and one of these is the use of 3D printing. 3D printing allows for creating physical replicas of items which may, due to great value or significance, not be handled by the public, or which are too small or fragile to be handled or even seen with the naked eye. One such application of new technologies has been welcomed by the National Museum in Bloemfontein, Free State, South Africa. Here, blown-up (enlarged) Museum specimens were 3D printed for various interactive exhibits that are aimed at increasing the accessibility of their permanent displays for visually impaired visitors who rely greatly on touch as a source of observation. A selection of scorpions, pseudoscorpions, mites and archetypal bird skulls were scanned, processed and 3D printed to produce enlarged, highly functional nylon models. This data paper provides the raw micro Computed Tomography (micro-CT) scan data and print ready STL files processed from this data. The STL files may be used in their current format and details of the printing are provided.
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Affiliation(s)
- Anton du Plessis
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa 7602, Corresponding author. CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Private bag X1, Matieland, 7602, Stellenbosch, South Africa. E-mail:
| | - Johan Els
- Department of Mechanical Engineering, Central University of Technology, Bloemfontein, South Africa 6001
| | - Stephan le Roux
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa 7602,Bruker microCT, Kontich, Belgium
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12
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Cloete KJ, Šmit Ž, Minnis-Ndimba R, Vavpetič P, du Plessis A, le Roux SG, Pelicon P. Physico-elemental analysis of roasted organic coffee beans from Ethiopia, Colombia, Honduras, and Mexico using X-ray micro-computed tomography and external beam particle induced X-ray emission. Food Chem X 2019; 2:100032. [PMID: 31432016 PMCID: PMC6694858 DOI: 10.1016/j.fochx.2019.100032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 05/16/2019] [Accepted: 05/17/2019] [Indexed: 11/17/2022] Open
Abstract
The physico-elemental profiles of commercially attained and roasted organic coffee beans from Ethiopia, Colombia, Honduras, and Mexico were compared using light microscopy, X-ray micro-computed tomography, and external beam particle induced X-ray emission. External beam PIXE analysis detected P, S, Cl, K, Ca, Ti, Mn, Fe, Cu, Zn, Br, Rb, and Sr in samples. Linear discriminant analysis showed that there was no strong association between elemental data and production region, whilst a heatmap combined with hierarchical clustering showed that soil-plant physico-chemical properties may influence regional elemental signatures. Physical trait data showed that Mexican coffee beans weighed significantly more than beans from other regions, whilst Honduras beans had the highest width. X-ray micro-computed tomography qualitative data showed heterogeneous microstructural features within and between beans representing different regions. In conclusion, such multi-dimensional analysis may present a promising tool in assessing the nutritional content and qualitative characteristics of food products such as coffee.
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Affiliation(s)
- Karen J. Cloete
- iThemba Laboratory for Accelerator Based Sciences, National Research Foundation, PO Box 722, Somerset West 7129, South Africa
| | - Žiga Šmit
- Jožef Stefan Institute, Jamova cesta 39, SI-1001 Ljubljana, Slovenia
- Faculty of Mathematics and Physics, University of Ljubljana, Jadranska ulica, 19, SI-1000 Ljubljana, Slovenia
| | - Roya Minnis-Ndimba
- iThemba Laboratory for Accelerator Based Sciences, National Research Foundation, PO Box 722, Somerset West 7129, South Africa
| | - Primož Vavpetič
- Jožef Stefan Institute, Jamova cesta 39, SI-1001 Ljubljana, Slovenia
| | - Anton du Plessis
- CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - Stephan G. le Roux
- CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa
| | - Primož Pelicon
- Jožef Stefan Institute, Jamova cesta 39, SI-1001 Ljubljana, Slovenia
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13
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Reid M, Bordy EM, Taylor WL, le Roux SG, du Plessis A. A micro X-ray computed tomography dataset of fossil echinoderms in an ancient obrution bed: a robust method for taphonomic and palaeoecologic analyses. Gigascience 2019; 8:5232983. [PMID: 30534956 PMCID: PMC6505446 DOI: 10.1093/gigascience/giy156] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 10/16/2018] [Accepted: 11/27/2018] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Taphonomic and palaeoecologic studies of obrution beds often employ conventional methods of investigation such as physical removal and extraction of fossils from their host rock (matrix) by mechanical preparation. This often-destructive method is not suitable for studying mold fossils, which are voids left in host rocks due to dissolution of the original organism in post-depositional processes. FINDINGS Microcomputed tomography (µCT) scan data of 24 fossiliferous rock samples revealed thousands of Paleozoic echinoderms. Digitally "stitching" together individually µCT scanned rock samples within three-dimensional (3D) space allows for quantifiable taphonomic data on a fossil echinoderm-rich obrution deposit from the Devonian (Emsian) of South Africa. Here, we provide a brief step-by-step guide on creating, segmenting, and ultimately combining sections of richly fossiliferous beds to create virtual models suited for the quantitative and qualitative taphonomic analyses of fossil invertebrate assemblages. CONCLUSIONS Visualizing the internal features of fossiliferous beds in 3D is an invaluable taphonomic tool for analyzing delicate fossils, accounting for all specimens irrespective of their preservation stages and with minimal damage. This technique is particularly useful for analyzing fossiliferous deposits with mold fossils that prove to be difficult to study with traditional methods, because the method relies on the large density contrast between the mold and host rock.
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Affiliation(s)
- Mhairi Reid
- Department of Geological Sciences, University of Cape Town, University Avenue, Upper Campus, Rondebosch, 7701, Cape Town, South Africa
| | - Emese M Bordy
- Department of Geological Sciences, University of Cape Town, University Avenue, Upper Campus, Rondebosch, 7701, Cape Town, South Africa
| | - Wendy L Taylor
- Department of Geological Sciences, University of Cape Town, University Avenue, Upper Campus, Rondebosch, 7701, Cape Town, South Africa
| | - Stephan G le Roux
- CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Private bag X1, Matieland, 7602, Stellenbosch, South Africa
| | - Anton du Plessis
- CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Private bag X1, Matieland, 7602, Stellenbosch, South Africa
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du Plessis A, Broeckhoven C. Looking deep into nature: A review of micro-computed tomography in biomimicry. Acta Biomater 2019; 85:27-40. [PMID: 30543937 DOI: 10.1016/j.actbio.2018.12.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 11/20/2018] [Accepted: 12/07/2018] [Indexed: 11/25/2022]
Abstract
Albert Einstein once said "look deep into nature, and then you will understand everything better". Looking deep into nature has in the last few years become much more achievable through the use of high-resolution X-ray micro-computed tomography (microCT). The non-destructive nature of microCT, combined with three-dimensional visualization and analysis, allows for the most complete internal and external "view" of natural materials and structures at both macro- and micro-scale. This capability brings with it the possibility to learn from nature at an unprecedented level of detail in full three dimensions, allowing us to improve our current understanding of structures, learn from them and apply them to solve engineering problems. The use of microCT in the fields of biomimicry, biomimetic engineering and bioinspiration is growing rapidly and holds great promise. MicroCT images and three-dimensional data can be used as generic bio-inspiration, or may be interpreted as detailed blueprints for specific engineering applications, i.e., reverse-engineering nature. In this review, we show how microCT has been used in bioinspiration and biomimetic studies to date, including investigations of multifunctional structures, hierarchical structures and the growing use of additive manufacturing and mechanical testing of 3D printed models in combination with microCT. The latest microCT capabilities and developments which might support biomimetic studies are described and the unique synergy between microCT and biomimicry is demonstrated. STATEMENT OF SIGNIFICANCE: This review highlights the growing use of X-ray micro computed tomography in biomimetic research. We feel the timing of this paper is excellent as there is a significant growth and interest in biomimetic research, also coupled with additive manufacturing, but still no review of the use of microCT in this field. The use of microCT for structural biomimetic and biomaterials research has huge potential but is still under-utilized, partly due to lack of knowledge of the capabilities and how it can be used in this field. We hope this review fills this gap and fuels further advances in this field using microCT.
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15
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du Plessis A, Broeckhoven C, le Roux SG. Snake fangs: 3D morphological and mechanical analysis by microCT, simulation, and physical compression testing. Gigascience 2018; 7:1-8. [PMID: 29267887 PMCID: PMC5765556 DOI: 10.1093/gigascience/gix126] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 12/07/2017] [Indexed: 11/14/2022] Open
Abstract
This Data Note provides data from an experimental campaign to analyse the detailed internal and external morphology and mechanical properties of venomous snake fangs. The aim of the experimental campaign was to investigate the evolutionary development of 3 fang phenotypes and investigate their mechanical behaviour. The study involved the use of load simulations to compare maximum Von Mises stress values when a load is applied to the tip of the fang. The conclusions of this study have been published elsewhere, but in this data note we extend the analysis, providing morphological comparisons including details such as curvature comparisons, thickness, etc. Physical compression results of individual fangs, though reported in the original paper, were also extended here by calculating the effective elastic modulus of the entire snake fang structure including internal cavities for the first time. This elastic modulus of the entire fang is significantly lower than the locally measured values previously reported from indentation experiments, highlighting the possibility that the elastic modulus is higher on the surface than in the rest of the material. The micro–computed tomography (microCT) data are presented both in image stacks and in the form of STL files, which simplifies the handling of the data and allows its re-use for future morphological studies. These fangs might also serve as bio-inspiration for future hypodermic needles.
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Affiliation(s)
- Anton du Plessis
- CT Scanner Facility, Stellenbosch University, Stellenbosch, Private bag X1, South Africa, 7602
| | - Chris Broeckhoven
- Department of Botany and Zoology, Stellenbosch University, Stellenbosch, Private bag X1, South Africa, 7602
| | - Stephan G le Roux
- CT Scanner Facility, Stellenbosch University, Stellenbosch, Private bag X1, South Africa, 7602
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du Plessis A, Sperling P, Beerlink A, du Preez WB, le Roux SG. Standard method for microCT-based additive manufacturing quality control 4: Metal powder analysis. MethodsX 2018; 5:1336-1345. [PMID: 30406023 PMCID: PMC6215023 DOI: 10.1016/j.mex.2018.10.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 10/11/2018] [Indexed: 10/31/2022] Open
Abstract
X-ray micro computed tomography (microCT) can be applied to analyse powder feedstock used in additive manufacturing. In this paper, we demonstrate a dedicated workflow for this analysis method, specifically for Ti6Al4V powder typically used in commercial powder bed fusion (PBF) additive manufacturing (AM) systems. The methodology presented includes sample size requirements, scan conditions and settings, reconstruction and image analysis procedures. We envisage this method will support standardization in powder analysis in the additive manufacturing community. This is aimed at ultimately improving the quality of additively manufactured parts, through the identification of impurities and defects in powders. •MicroCT analysis of metal powders for additive manufacturing•Method describes a standard workflow simplifying usage of the technique•Sample requirements and image analysis workflow is described.
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Affiliation(s)
- Anton du Plessis
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa
| | | | | | - Willie B du Preez
- Dept of Mechanical Engineering Dept, Central University of Technology, Free State, South Africa
| | - Stephan G le Roux
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa
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17
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Landschoff J, Komai T, du Plessis A, Gouws G, Griffiths CL. MicroCT imaging applied to description of a new species of Pagurus Fabricius, 1775 (Crustacea: Decapoda: Anomura: Paguridae), with selection of three-dimensional type data. PLoS One 2018; 13:e0203107. [PMID: 30256803 PMCID: PMC6157836 DOI: 10.1371/journal.pone.0203107] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 08/14/2018] [Indexed: 01/06/2023] Open
Abstract
A new species of hermit crab, Pagurus fraserorum n. sp. (family Paguridae) is described from rocky subtidal reefs off KwaZulu-Natal, South Africa, and illustrated using both conventional drawings and colour photographs, and via three-dimensional (3D) X-ray micro-computed tomography (μCT). Because of the limitation μCT has in detecting very fine and soft structures, a novel approach of manually drawing setation and spinulation onto the two-dimensional images of the 3D visualizations was used to illustrate the pereopods. In addition, an interactive figure and rotation movie clips in the supplement section complement the species description, and the 3D raw data of the 3D type data are downloadable from the Gigascience Database repository. The new species is the sixth species of Pagurus Fabricius, 1775 reported from South Africa and is closely allied to the Indo-Pacific P. boriaustraliensis Morgen, 1990 and P. pitagsaleei McLaughlin, 2002, from which it differs by its shorter ocular peduncles, by the armature of the carpus of the right cheliped, and also in colouration. This study presents the first description of a hermit crab in which a majority of taxonomic details are illustrated through 3D volume-rendered illustrations. In addition, colour photographs and COI molecular barcodes are provided, and the latter compared to COI sequences of specimens from Western Australia previously identified as P. boriaustraliensis and of specimens of P. pitagsaleei from Taiwan, as well as to three additional South African members of the genus. The South African taxon was confirmed to be genetically distinct from all species tested.
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Affiliation(s)
- Jannes Landschoff
- Department of Biological Sciences and Marine Research Institute, University of Cape Town, Rondebosch, Western Cape, South Africa
| | - Tomoyuki Komai
- Natural History Museum and Institute, Aoba-cho, Chuo-ku, Chiba, Japan
| | - Anton du Plessis
- CT Scanner, Central Analytical Facility, Stellenbosch University, Stellenbosch, Western Cape, South Africa
| | - Gavin Gouws
- National Research Foundation–South African Institute for Aquatic Biodiversity, Grahamstown, Eastern Cape, South Africa
| | - Charles L. Griffiths
- Department of Biological Sciences and Marine Research Institute, University of Cape Town, Rondebosch, Western Cape, South Africa
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du Plessis A, Sperling P, Beerlink A, Tshabalala L, Hoosain S, Mathe N, le Roux SG. Standard method for microCT-based additive manufacturing quality control 2: Density measurement. MethodsX 2018; 5:1117-1123. [PMID: 30294559 PMCID: PMC6168933 DOI: 10.1016/j.mex.2018.09.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 09/11/2018] [Indexed: 11/25/2022] Open
Abstract
MicroCT is best known for its ability to detect and quantify porosity or defects, and to visualize its 3D distribution. However, it is also possible to obtain accurate volumetric measurements from parts – this can be used in combination with the part mass to provide a good measure of its average density. The advantage of this density-measurement method is the ability to combine the density measurement with visualization and other microCT analyses of the same sample. These other analyses may include detailed porosity or void analysis (size and distribution) and roughness assessment, obtainable with the same scan data. Simple imaging of the interior of the sample allows the detection of unconsolidated powder, open porosity to the surface or the presence of inclusions. The CT density method presented here makes use of a 10 mm cube sample and a simple data analysis workflow, facilitating standardization of the method. A laboratory microCT scanner is required at 15 μm voxel size, suitable software to allow sub-voxel precise edge determination of the scanned sample and hence an accurate total volume measurement, and a scale with accuracy to 3 digits. MicroCT-based mean density measurement method. Accurate volume measurement and scale mass. 10 mm cube sample allows standardization and automation of workflow.
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Affiliation(s)
- Anton du Plessis
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa
| | | | | | - Lerato Tshabalala
- National Laser Centre, Council for Scientific and Industrial Research, South Africa
| | - Shaik Hoosain
- National Laser Centre, Council for Scientific and Industrial Research, South Africa
| | - Ntombi Mathe
- National Laser Centre, Council for Scientific and Industrial Research, South Africa
| | - Stephan G le Roux
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa
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du Plessis A, Sperling P, Beerlink A, Tshabalala L, Hoosain S, Mathe N, le Roux SG. Standard method for microCT-based additive manufacturing quality control 1: Porosity analysis. MethodsX 2018; 5:1102-1110. [PMID: 30271722 PMCID: PMC6159003 DOI: 10.1016/j.mex.2018.09.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 09/11/2018] [Indexed: 10/28/2022] Open
Abstract
MicroCT is a well-established technique that is used to analyze the interior of objects non-destructively, and it is especially useful for void or porosity analysis. Besides its widespread use, few standards exist and none for additive manufacturing as yet. This is due to the inherent differences in part design, sizes and geometries, which results in different scan resolutions and qualities. This makes direct comparison between different scans of additively manufactured parts almost impossible. In addition, different image analysis methodologies can produce different results. In this method paper, we present a simplified 10 mm cube-shaped coupon sample as a standard size for detailed analysis of porosity using microCT, and a simplified workflow for obtaining porosity information. The aim is to be able to obtain directly comparable porosity information from different samples from the same AM system and even from different AM systems, and to potentially correlate detailed morphologies of the pores or voids with improper process parameters. The method is applied to two examples of different characteristic types of voids in AM: sub-surface lack of fusion due to improper contour scanning, and tree-like pores growing in the build direction. This standardized method demonstrates the capability for microCT to not only quantify porosity, but also identify void types which can be used to improve AM process optimization.
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Affiliation(s)
- Anton du Plessis
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa
| | | | | | - Lerato Tshabalala
- National Laser Centre, Council for Scientific and Industrial Research, South Africa
| | - Shaik Hoosain
- National Laser Centre, Council for Scientific and Industrial Research, South Africa
| | - Ntombi Mathe
- National Laser Centre, Council for Scientific and Industrial Research, South Africa
| | - Stephan G le Roux
- CT Scanner Facility, Stellenbosch University, Stellenbosch, South Africa
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du Plessis A, Broeckhoven C, Yadroitsev I, Yadroitsava I, le Roux SG. Analyzing nature's protective design: The glyptodont body armor. J Mech Behav Biomed Mater 2018; 82:218-223. [DOI: 10.1016/j.jmbbm.2018.03.037] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 03/26/2018] [Accepted: 03/28/2018] [Indexed: 11/16/2022]
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21
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du Plessis A, Broeckhoven C, Guelpa A, le Roux SG. Laboratory x-ray micro-computed tomography: a user guideline for biological samples. Gigascience 2018; 6:1-11. [PMID: 28419369 PMCID: PMC5449646 DOI: 10.1093/gigascience/gix027] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 04/09/2017] [Indexed: 11/23/2022] Open
Abstract
Laboratory x-ray micro–computed tomography (micro-CT) is a fast-growing method in scientific research applications that allows for non-destructive imaging of morphological structures. This paper provides an easily operated “how to” guide for new potential users and describes the various steps required for successful planning of research projects that involve micro-CT. Background information on micro-CT is provided, followed by relevant setup, scanning, reconstructing, and visualization methods and considerations. Throughout the guide, a Jackson's chameleon specimen, which was scanned at different settings, is used as an interactive example. The ultimate aim of this paper is make new users familiar with the concepts and applications of micro-CT in an attempt to promote its use in future scientific studies.
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Affiliation(s)
- Anton du Plessis
- CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Stellenbosch, 7602, South Africa.,Physics Department, Stellenbosch University, Stellenbosch, 7602, South Africa
| | - Chris Broeckhoven
- Department of Botany and Zoology, Stellenbosch University, Stellenbosch, 7602, South Africa
| | - Anina Guelpa
- CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Stellenbosch, 7602, South Africa
| | - Stephan Gerhard le Roux
- CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Stellenbosch, 7602, South Africa
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22
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Abstract
Abstract
Herpetological research, like any other (palaeo)biological science, relies heavily on accurate data collection, particularly visualisation and quantification of anatomical features. While several high-resolution imaging methods are currently available, one technique in particular, x-ray microtomography or micro-computed tomography, is on the verge of revolutionising our understanding of the morphology of amphibians and reptiles. Here, we present a review on the prevalence and trends of x-ray microtomography in herpetological studies carried out over the last two decades. We describe its current use, provide practical guidelines for future research that focusses on the morphological study of reptiles and amphibians, and highlight emerging trends including soft-tissue and in vivo scanning. Furthermore, while x-ray microtomography is a rapidly evolving field with great potential, various important drawbacks are associated with its use, including sample size effect and measurement errors resulting from differences in spatial resolution and preparation techniques. By providing recommendations to overcome these hurdles, we ultimately aim to maximise the benefits of x-ray microtomography to herpetological research.
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Affiliation(s)
- Chris Broeckhoven
- 1Laboratory of Functional Morphology, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Anton du Plessis
- 2CT Scanner Facility, Stellenbosch University, Matieland, 7602 Stellenbosch, South Africa
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23
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Schoeman L, du Plessis A, Verboven P, Nicolaï BM, Cantre D, Manley M. Effect of oven and forced convection continuous tumble (FCCT) roasting on the microstructure and dry milling properties of white maize. INNOV FOOD SCI EMERG 2017. [DOI: 10.1016/j.ifset.2017.07.021] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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24
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Broeckhoven C, du Plessis A. Has snake fang evolution lost its bite? New insights from a structural mechanics viewpoint. Biol Lett 2017; 13:rsbl.2017.0293. [PMID: 28768797 DOI: 10.1098/rsbl.2017.0293] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Accepted: 07/11/2017] [Indexed: 11/12/2022] Open
Abstract
Venomous snakes-the pinnacle of snake evolution-are characterized by their possession of venom-conducting fangs ranging from grooved phenotypes characterizing multiple lineages of rear-fanged taxa to tubular phenotypes present in elapids, viperids and atractaspidines. Despite extensive research, controversy still exists on the selective pressures involved in fang phenotype diversification. Here, we test the hypothesis that larger fangs and consequently a shift to an anterior position in the maxilla evolved to compensate for the costs of structural changes, i.e. higher stress upon impact in tubular fangs compared to grooved fangs. Direct voxel-based stress simulations conducted on high-resolution µCT scans, analysed within a phylogenetic framework, showed no differences in stress distribution between the three fang phenotypes, despite differences in (relative) fang length. These findings suggest that additional compensatory mechanisms are responsible for the biomechanical optimization and that fang length might instead be related to differential striking behaviour strategies.
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Affiliation(s)
- Chris Broeckhoven
- Department of Botany and Zoology, Stellenbosch University, Stellenbosch, South Africa
| | - Anton du Plessis
- CT Scanner Facility, Central Analytical Facilities, Stellenbosch University, Stellenbosch, South Africa
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25
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Grine FE, Marean CW, Faith JT, Black W, Mongle CS, Trinkaus E, le Roux SG, du Plessis A. Further human fossils from the Middle Stone Age deposits of Die Kelders Cave 1, Western Cape Province, South Africa. J Hum Evol 2017; 109:70-78. [DOI: 10.1016/j.jhevol.2017.05.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 05/21/2017] [Accepted: 05/22/2017] [Indexed: 10/19/2022]
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Guelpa A, Marini F, du Plessis A, Slabbert R, Manley M. Verification of authenticity and fraud detection in South African honey using NIR spectroscopy. Food Control 2017. [DOI: 10.1016/j.foodcont.2016.11.002] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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27
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Swart C, Khoza A, Khan K, Roux SL, Plessis AD, Loos B. Investigating Basal Autophagic Activity in Brain Regions Associated with Neurodegeneration using In Vivo and Ex Vivo Models. ACTA ACUST UNITED AC 2017. [DOI: 10.4172/2161-0460.1000337] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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28
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Guelpa A, du Plessis A, Manley M. A high-throughput X-ray micro-computed tomography (μCT) approach for measuring single kernel maize ( Zea mays L.) volumes and densities. J Cereal Sci 2016. [DOI: 10.1016/j.jcs.2016.04.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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29
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Schoeman L, Williams P, du Plessis A, Manley M. X-ray micro-computed tomography (μCT) for non-destructive characterisation of food microstructure. Trends Food Sci Technol 2016. [DOI: 10.1016/j.tifs.2015.10.016] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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30
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du Plessis A, le Roux SG, Els J, Booysen G, Blaine DC. Application of microCT to the non-destructive testing of an additive manufactured titanium component. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.csndt.2015.09.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Forbes A, Dickey F, DeGama M, du Plessis A. Wavelength tunable laser beam shaping. Opt Lett 2012; 37:49-51. [PMID: 22212787 DOI: 10.1364/ol.37.000049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Laser beam shaping by phase-only transformations, often referred to as field mapping, has for a long time been considered wavelength dependent. In this Letter we outline a simple mathematical argument that shows how the problem may be formulated in a wavelength tunable manner, requiring only a minor adjustment in the observation plane. We verify the theoretical prediction by experiment using the example of a Gaussian-to-flattop-beam transformation, and we show that the shaping is valid across a wide range of wavelengths for a single diffractive optical element.
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Affiliation(s)
- Andrew Forbes
- Council for Scientific and Industrial Research (CSIR), P.O. Box 395, Pretoria 0001, South Africa.
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Abstract
Bimolecular chemical reaction control of gaseous CO and H(2) at room temperature and atmospheric pressure, without any catalyst, using shaped femtosecond laser pulses is presented. High intensity laser radiation applied to a reaction cell facilitates non-resonant bond breakage and the formation of a range of ions, which can then react to form new products. Stable reaction products are measured after irradiation of a reaction cell, using time of flight mass spectroscopy. Bond formation of C-O, C-C, and C-H bonds is demonstrated as CO(2)(+), C(2)H(2)(+), CH(+), and CH(3)(+) were observed in the time of flight mass spectrum of the product gas, analyzed after irradiation. The formation of CO(2) is shown to be dependent on laser intensity, irradiation time, and on the presence of H(2) in the reaction cell. Using negatively chirped laser pulses more C-O bond formation takes place as compared to more C-C bond formation for unchirped pulses.
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