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Grijalva Garces D, Strauß S, Gretzinger S, Schmieg B, Jüngst T, Groll J, Meinel L, Schmidt I, Hartmann H, Schenke-Layland K, Brandt N, Selzer M, Zimmermann S, Koltay P, Southan A, Tovar GEM, Schmidt S, Weber A, Ahlfeld T, Gelinsky M, Scheibel T, Detsch R, Boccaccini AR, Naolou T, Lee-Thedieck C, Willems C, Groth T, Allgeier S, Köhler B, Friedrich T, Briesen H, Buchholz J, Paulus D, von Gladiss A, Hubbuch J. On the reproducibility of extrusion-based bioprinting: round robin study on standardization in the field. Biofabrication 2023; 16:015002. [PMID: 37769669 DOI: 10.1088/1758-5090/acfe3b] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 09/25/2023] [Indexed: 10/03/2023]
Abstract
The outcome of three-dimensional (3D) bioprinting heavily depends, amongst others, on the interaction between the developed bioink, the printing process, and the printing equipment. However, if this interplay is ensured, bioprinting promises unmatched possibilities in the health care area. To pave the way for comparing newly developed biomaterials, clinical studies, and medical applications (i.e. printed organs, patient-specific tissues), there is a great need for standardization of manufacturing methods in order to enable technology transfers. Despite the importance of such standardization, there is currently a tremendous lack of empirical data that examines the reproducibility and robustness of production in more than one location at a time. In this work, we present data derived from a round robin test for extrusion-based 3D printing performance comprising 12 different academic laboratories throughout Germany and analyze the respective prints using automated image analysis (IA) in three independent academic groups. The fabrication of objects from polymer solutions was standardized as much as currently possible to allow studying the comparability of results from different laboratories. This study has led to the conclusion that current standardization conditions still leave room for the intervention of operators due to missing automation of the equipment. This affects significantly the reproducibility and comparability of bioprinting experiments in multiple laboratories. Nevertheless, automated IA proved to be a suitable methodology for quality assurance as three independently developed workflows achieved similar results. Moreover, the extracted data describing geometric features showed how the function of printers affects the quality of the printed object. A significant step toward standardization of the process was made as an infrastructure for distribution of material and methods, as well as for data transfer and storage was successfully established.
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Affiliation(s)
- David Grijalva Garces
- Institute of Functional Interfaces, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
- Institute of Process Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Svenja Strauß
- Institute of Functional Interfaces, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
- Institute of Process Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Sarah Gretzinger
- Institute of Functional Interfaces, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
- Institute of Process Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Barbara Schmieg
- Institute of Functional Interfaces, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
- Institute of Process Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Tomasz Jüngst
- Department for Functional Materials in Medicine and Dentistry, Institute of Functional Materials and Biofabrication, University of Würzburg, Würzburg, Germany
- Bavarian Polymer Institute, University of Bayreuth, Bayreuth, Germany
| | - Jürgen Groll
- Department for Functional Materials in Medicine and Dentistry, Institute of Functional Materials and Biofabrication, University of Würzburg, Würzburg, Germany
- Bavarian Polymer Institute, University of Bayreuth, Bayreuth, Germany
| | - Lorenz Meinel
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Würzburg, Germany
| | - Isabelle Schmidt
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Hanna Hartmann
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Katja Schenke-Layland
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
- Institute of Biomedical Engineering, Department for Medical Technologies and Regenerative Medicine, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Nico Brandt
- Institute for Applied Materials, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Michael Selzer
- Institute for Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Stefan Zimmermann
- Laboratory for MEMS Applications, Department of Microsystems Engineering, University of Freiburg, Freiburg, Germany
| | - Peter Koltay
- Laboratory for MEMS Applications, Department of Microsystems Engineering, University of Freiburg, Freiburg, Germany
| | - Alexander Southan
- Institute of Interfacial Process Engineering and Plasma Technology, University of Stuttgart, Stuttgart, Germany
- Functional Surfaces and Materials, Fraunhofer Institute for Interfacial Engineering and Biotechnology, Stuttgart, Germany
| | - Günter E M Tovar
- Institute of Interfacial Process Engineering and Plasma Technology, University of Stuttgart, Stuttgart, Germany
- Functional Surfaces and Materials, Fraunhofer Institute for Interfacial Engineering and Biotechnology, Stuttgart, Germany
| | - Sarah Schmidt
- Functional Surfaces and Materials, Fraunhofer Institute for Interfacial Engineering and Biotechnology, Stuttgart, Germany
| | - Achim Weber
- Functional Surfaces and Materials, Fraunhofer Institute for Interfacial Engineering and Biotechnology, Stuttgart, Germany
| | - Tilman Ahlfeld
- Center for Translational Bone, Joint, and Soft Tissue Research, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
| | - Michael Gelinsky
- Center for Translational Bone, Joint, and Soft Tissue Research, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
| | - Thomas Scheibel
- Bavarian Polymer Institute, University of Bayreuth, Bayreuth, Germany
- Chair of Biomaterials, University of Bayreuth, Bayreuth, Germany
| | - Rainer Detsch
- Institute of Biomaterials, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Aldo R Boccaccini
- Institute of Biomaterials, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany
| | - Toufik Naolou
- Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hannover, Germany
| | - Cornelia Lee-Thedieck
- Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hannover, Germany
| | - Christian Willems
- Department Biomedical Materials, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Thomas Groth
- Department Biomedical Materials, Martin Luther University Halle-Wittenberg, Halle (Saale), Germany
| | - Stephan Allgeier
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | - Bernd Köhler
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | - Tiaan Friedrich
- Process Systems Engineering, School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Heiko Briesen
- Process Systems Engineering, School of Life Sciences, Technical University of Munich, Freising, Germany
| | - Janine Buchholz
- Institute for Computational Visualistics, Active Vision Group, University of Koblenz, Koblenz, Germany
| | - Dietrich Paulus
- Institute for Computational Visualistics, Active Vision Group, University of Koblenz, Koblenz, Germany
| | - Anselm von Gladiss
- Institute for Computational Visualistics, Active Vision Group, University of Koblenz, Koblenz, Germany
| | - Jürgen Hubbuch
- Institute of Functional Interfaces, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
- Institute of Process Engineering in Life Sciences, Section IV: Biomolecular Separation Engineering, Karlsruhe Institute of Technology, Karlsruhe, Germany
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2
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Alwazani H, Chaaban A. IRS-Enabled Ultra-Low-Power Wireless Sensor Networks: Scheduling and Transmission Schemes. Sensors (Basel) 2022; 22:9229. [PMID: 36501931 PMCID: PMC9737329 DOI: 10.3390/s22239229] [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] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/15/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
Passive technologies, including intelligent reflecting surfaces (IRS), are gaining traction thanks to their ability to enhance communication systems while maintaining minimal cost and low complexity. They can assist a wireless sensor network (WSN) by achieving low power requirements for sensors and aid communication needs in many applications, for instance, environmental monitoring. In this paper, we propose an IRS-equipped WSN which describes sensors equipped with IRSs instead of active radio frequency (RF) electronics. The IRS sensor node (ISN) intercepts a dedicated signal from a power source such as a base station (BS) and modulates the transmission of that signal to an intended recipient. In order to enable multiple sensors to transmit to the receiver, we study opportunistic scheduling (OS) utilizing multi-sensor diversity while considering blind IRS operation, and compare it with round-robin (RR), proportional fairness (PF), and a theoretical upper bound. We study the effect of the choice of the number of IRS elements N and number of ISNs L on the average throughput of the system under OS. Finally, we provide pertinent comparisons for the different scheduling schemes and IRS configurations under relevant system performance metrics, highlighting different scenarios in which each scheme performs better.
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Ziolkowski P, Blaschkewitz P, Ryu B, Park S, Müller E. International Round Robin Test of Thermoelectric Generator Modules. Materials (Basel) 2022; 15:1627. [PMID: 35268858 DOI: 10.3390/ma15051627] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/17/2022] [Accepted: 02/18/2022] [Indexed: 11/16/2022]
Abstract
The status of metrology for the characterization of thermoelectric generator modules (TEM) is investigated in this work by an international round robin (RR) test including twelve laboratories from nine countries on three continents. Measurements have been performed with three samples of a Bi2Te3-based commercial TEM type, which has prevailed over three competing types during previous tests on the short- and long-term stability. A comparison of temperature-dependent results is provided up to 200 °C hot side temperature for the maximum power output Pmax, the incident heat flow Q˙In (at maximum efficiency conditions), and the maximum efficiency ηmax. Data evaluation from all RR participants reveals maximum standard deviations for these measurands of 27.2% (Pmax), 59.2% (Q˙In), and 25.9% (ηmax). A comparison between RR data sets and reference data from manufacturer specifications shows high deviations of up to 46%, too. These deviations reflect the absence of measurement guidelines and reference samples and confirm the need for improvements in the standardization of TEM metrology. Accordingly, the results of the RR are presented against the background of our own investigations on the uncertainty budgets for the determination of the abovementioned TEM properties using inhouse-developed characterization facilities, which comprise reference and absolute measurement techniques for the determination of heat flow.
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4
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Litina C, Bumanis G, Anglani G, Dudek M, Maddalena R, Amenta M, Papaioannou S, Pérez G, García Calvo JL, Asensio E, Beltrán Cobos R, Tavares Pinto F, Augonis A, Davies R, Guerrero A, Sánchez Moreno M, Stryszewska T, Karatasios I, Tulliani JM, Antonaci P, Bajare D, Al-Tabbaa A. Evaluation of Methodologies for Assessing Self-Healing Performance of Concrete with Mineral Expansive Agents: An Interlaboratory Study. Materials (Basel) 2021; 14:2024. [PMID: 33920620 DOI: 10.3390/ma14082024] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 04/04/2021] [Accepted: 04/14/2021] [Indexed: 11/17/2022]
Abstract
Self-healing concrete has the potential to optimise traditional design approaches; however, commercial uptake requires the ability to harmonize against standardized frameworks. Within EU SARCOS COST Action, different interlaboratory tests were executed on different self-healing techniques. This paper reports on the evaluation of the effectiveness of proposed experimental methodologies suited for self-healing concrete with expansive mineral additions. Concrete prisms and discs with MgO-based healing agents were produced and precracked. Water absorption and water flow tests were executed over a healing period spanning 6 months to assess the sealing efficiency, and the crack width reduction with time was monitored. High variability was reported for both reference (REF) and healing-addition (ADD) series affecting the reproducibility of cracking. However, within each lab, the crack width creation was repeatable. ADD reported larger crack widths. The latter influenced the observed healing making direct comparisons across labs prone to errors. Water absorption tests highlighted were susceptible to application errors. Concurrently, the potential of water flow tests as a facile method for assessment of healing performance was shown across all labs. Overall, the importance of repeatability and reproducibility of testing methods is highlighted in providing a sound basis for incorporation of self-healing concepts in practical applications.
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5
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Alankar B, Sharma G, Kaur H, Valverde R, Chang V. Experimental Setup for Investigating the Efficient Load Balancing Algorithms on Virtual Cloud. Sensors (Basel) 2020; 20:s20247342. [PMID: 33371361 PMCID: PMC7767358 DOI: 10.3390/s20247342] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 12/02/2022]
Abstract
Cloud computing has emerged as the primary choice for developers in developing applications that require high-performance computing. Virtualization technology has helped in the distribution of resources to multiple users. Increased use of cloud infrastructure has led to the challenge of developing a load balancing mechanism to provide optimized use of resources and better performance. Round robin and least connections load balancing algorithms have been developed to allocate user requests across a cluster of servers in the cloud in a time-bound manner. In this paper, we have applied the round robin and least connections approach of load balancing to HAProxy, virtual machine clusters and web servers. The experimental results are visualized and summarized using Apache Jmeter and a further comparative study of round robin and least connections is also depicted. Experimental setup and results show that the round robin algorithm performs better as compared to the least connections algorithm in all measuring parameters of load balancer in this paper.
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Affiliation(s)
- Bhavya Alankar
- Department of Computer Science and Engineering, School of Engineering Sciences and Technology, Jamia Hamdard, New Delhi 110062, India; (B.A.); (G.S.)
| | - Gaurav Sharma
- Department of Computer Science and Engineering, School of Engineering Sciences and Technology, Jamia Hamdard, New Delhi 110062, India; (B.A.); (G.S.)
| | - Harleen Kaur
- Department of Computer Science and Engineering, School of Engineering Sciences and Technology, Jamia Hamdard, New Delhi 110062, India; (B.A.); (G.S.)
- Correspondence: (H.K.); or (V.C.)
| | - Raul Valverde
- John Molson School of Business, Concordia University, Montreal, QC G1X 3X4, Canada;
| | - Victor Chang
- Artificial Intelligence and Information Systems Research Group, School of Computing, Engineering and Digital Technologies, Teesside University, Middlesbrough TS1 3BX, UK
- Correspondence: (H.K.); or (V.C.)
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6
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Keppens C, Tack V, Dufraing K, Rouleau E, Ligtenberg MJL, Schuuring E, Dequeker EMC. Variation in nomenclature of somatic variants for selection of oncological therapies: Can we reach a consensus soon? Hum Mutat 2019; 41:7-16. [PMID: 31553104 PMCID: PMC6973115 DOI: 10.1002/humu.23926] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [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: 04/19/2019] [Revised: 09/05/2019] [Accepted: 09/24/2019] [Indexed: 12/13/2022]
Abstract
A standardized nomenclature for reporting oncology biomarker variants is key to avoid misinterpretation of results and unambiguous registration in clinical databases. External quality assessment (EQA) schemes have revealed a need for more consistent nomenclature use in clinical genetics. We evaluated the propensity of EQA for improvement of compliance with Human Genome Variation Society (HGVS) recommendations for reporting of predictive somatic variants in lung and colorectal cancer. Variant entries between 2012 and 2018 were collected from written reports and electronic results sheets. In total, 4,053 variants were assessed, of which 12.1% complied with HGVS recommendations. Compliance improved over time from 2.1% (2012) to 22.3% (2018), especially when laboratories participated in multiple EQA schemes. Compliance was better for next-generation sequencing (20.9%) compared with targeted techniques (9.8%). In the 1792 reports, HGVS recommendations for reference sequences were met for 31.9% of reports, for 36.0% of noncommercial, and 26.5% of commercial test methods. Compliance improved from 16.7% (2012) to 33.1% (2018), and after repeated EQA participation. EQA participation improves compliance with HGVS recommendations. The residual percentage of errors in the most recent schemes suggests that laboratories, companies, and EQA providers need to collaborate for additional improvement of harmonization in clinical test reporting.
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Affiliation(s)
- Cleo Keppens
- Department of Public Health and Primary Care, Biomedical Quality Assurance Research Unit, University of Leuven, Leuven, Belgium
| | - Véronique Tack
- Department of Public Health and Primary Care, Biomedical Quality Assurance Research Unit, University of Leuven, Leuven, Belgium
| | - Kelly Dufraing
- Department of Public Health and Primary Care, Biomedical Quality Assurance Research Unit, University of Leuven, Leuven, Belgium
| | - Etienne Rouleau
- Gustave Roussy, Service de Génétique/Pathologie Moléculaire, Villejuif Cedex, France
| | - Marjolijn J L Ligtenberg
- Department of Pathology and Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Ed Schuuring
- University Medical Center Groningen, Department of Pathology, University of Groningen, Groningen, The Netherlands
| | - Elisabeth M C Dequeker
- Department of Public Health and Primary Care, Biomedical Quality Assurance Research Unit, University of Leuven, Leuven, Belgium
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7
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Mollenhauer B, Bowman FD, Drake D, Duong J, Blennow K, El-Agnaf O, Shaw LM, Masucci J, Taylor P, Umek RM, Dunty JM, Smith CL, Stoops E, Vanderstichele H, Schmid AW, Moniatte M, Zhang J, Kruse N, Lashuel HA, Teunissen C, Schubert T, Dave KD, Hutten SJ, Zetterberg H. Antibody-based methods for the measurement of α-synuclein concentration in human cerebrospinal fluid - method comparison and round robin study. J Neurochem 2018; 149:126-138. [PMID: 30125936 PMCID: PMC6587944 DOI: 10.1111/jnc.14569] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [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: 04/06/2018] [Revised: 07/06/2018] [Accepted: 08/15/2018] [Indexed: 01/12/2023]
Abstract
α‐Synuclein is the major component of Lewy bodies and a candidate biomarker for neurodegenerative diseases in which Lewy bodies are common, including Parkinson's disease and dementia with Lewy bodies. A large body of literature suggests that these disorders are characterized by reduced concentrations of α‐synuclein in cerebrospinal fluid (CSF), with overlapping concentrations compared to healthy controls and variability across studies. Several reasons can account for this variability, including technical ones, such as inter‐assay and inter‐laboratory variation (reproducibility). We compared four immunochemical methods for the quantification of α‐synuclein concentration in 50 unique CSF samples. All methods were designed to capture most of the existing α‐synuclein forms in CSF (‘total’ α‐synuclein). Each of the four methods showed high analytical precision, excellent correlation between laboratories (R2 0.83–0.99), and good correlation with each other (R2 0.64–0.93), although the slopes of the regression lines were different between the four immunoassays. The use of common reference CSF samples decreased the differences in α‐synuclein concentration between detection methods and technologies. Pilot data on an immunoprecipitation mass spectrometry (IP‐MS) method is also presented. Our results suggest that the four immunochemical methods and the IP‐MS method measure similar forms of α‐synuclein and that a common reference material would allow harmonization of results between immunoassays. ![]()
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Affiliation(s)
- Brit Mollenhauer
- Paracelsus-Elena-Klinik, Kassel, Germany.,Department of Neurology, University Medical Center, Goettingen, Germany
| | - Frederick DuBois Bowman
- Department of Biostatistics, Columbia University, Mailman School of Public Health, New York City, New York, USA
| | - Daniel Drake
- Department of Biostatistics, Columbia University, Mailman School of Public Health, New York City, New York, USA
| | - Jimmy Duong
- Department of Biostatistics, Columbia University, Mailman School of Public Health, New York City, New York, USA
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Omar El-Agnaf
- Neurological Disorders Research Center, Qatar Biomedical Research Institute (QBRI), and College of Science and Engineering, HBKU, Education City, Qatar Foundation, Doha, Qatar
| | - Leslie M Shaw
- Department of Pathology & Laboratory Medicine and Center for Neurodegenerative Disease Research, Institute on Aging, University of Pennsylvania, Philadelphia, PA, USA
| | | | | | | | | | | | | | | | - Adrian W Schmid
- Proteomics Core Facility, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Marc Moniatte
- Proteomics Core Facility, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Jing Zhang
- University of Washington, Seattle, WA, USA
| | - Niels Kruse
- Institute of Neuropathology, University Medical Center, Goettingen, Germany
| | - Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, Institute of Physics of Biological Systems, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland
| | | | | | - Kuldip D Dave
- Michael J. Fox Foundation for Parkinson's Research, New York City, New York, USA
| | - Samantha J Hutten
- Michael J. Fox Foundation for Parkinson's Research, New York City, New York, USA
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.,Department of Molecular Neuroscience, UCL Institute of Neurology, Queens Square, London, UK.,UK Dementia Research Institute at UCL, London, UK
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8
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Chantler CT, Bunker BA, Abe H, Kimura M, Newville M, Welter E. A call for a round robin study of XAFS stability and platform dependence at synchrotron beamlines on well defined samples. J Synchrotron Radiat 2018; 25:935-943. [PMID: 29979153 PMCID: PMC6038608 DOI: 10.1107/s1600577518003752] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 03/04/2018] [Indexed: 05/31/2023]
Abstract
Round robin studies have been used across fields of science for quality control testing and to investigate laboratory dependencies and cross-platform inconsistencies as well as to drive forward the improvement of understanding of experimental systems, systematic effects and theoretical limitations. Here, following the Q2XAFS Workshop and Satellite to IUCr Congress 2017 on `Data Acquisition, Treatment, Storage - quality assurance in XAFS spectroscopy', a mechanism is suggested for a suitable study across XAFS (X-ray absorption fine-structure) beamlines and facilities, to enable each beamline to cross-calibrate, provide representative test data, and to enable collaborative cross-facility activities to be more productive.
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Affiliation(s)
| | - Bruce A. Bunker
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, IN, USA
| | - Hitoshi Abe
- Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
| | - Masao Kimura
- Department of Materials Structure Science, School of High Energy Accelerator Science, SOKENDAI (The Graduate University for Advanced Studies), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
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9
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Maruta K, Furukawa H. Highly Efficient Multi Channel Packet Forwarding with Round Robin Intermittent Periodic Transmit for Multihop Wireless Backhaul Networks. Sensors (Basel) 2017; 17:s17112609. [PMID: 29137164 PMCID: PMC5713633 DOI: 10.3390/s17112609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 11/09/2017] [Accepted: 11/10/2017] [Indexed: 11/16/2022]
Abstract
Round Robin based Intermittent Periodic Transmit (RR-IPT) has been proposed which achieves highly efficient multi-hop relays in multi-hop wireless backhaul networks (MWBN) where relay nodes are 2-dimensionally deployed. This paper newly investigates multi-channel packet scheduling and forwarding scheme for RR-IPT. Downlink traffic is forwarded by RR-IPT via one of the channels, while uplink traffic and part of downlink are accommodated in the other channel. By comparing IPT and carrier sense multiple access with collision avoidance (CSMA/CA) for uplink/downlink packet forwarding channel, IPT is more effective in reducing packet loss rate whereas CSMA/CA is better in terms of system throughput and packet delay improvement.
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Affiliation(s)
- Kazuki Maruta
- Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
| | - Hiroshi Furukawa
- Graduate School of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
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10
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Pauw BR, Kästner C, Thünemann AF. Nanoparticle size distribution quantification: results of a small-angle X-ray scattering inter-laboratory comparison. J Appl Crystallogr 2017; 50:1280-1288. [PMID: 29021732 PMCID: PMC5627679 DOI: 10.1107/s160057671701010x] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [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: 03/28/2017] [Accepted: 07/07/2017] [Indexed: 12/20/2022] Open
Abstract
This paper presents the first worldwide inter-laboratory comparison of small-angle X-ray scattering (SAXS) for nanoparticle sizing. The measurands in this comparison are the mean particle radius, the width of the size distribution and the particle concentration. The investigated sample consists of dispersed silver nanoparticles, surrounded by a stabilizing polymeric shell of poly(acrylic acid). The silver cores dominate the X-ray scattering pattern, leading to the determination of their radius size distribution using (i) the generalized indirect Fourier transformation method, (ii) classical model fitting using SASfit and (iii) a Monte Carlo fitting approach using McSAS. The application of these three methods to the collected data sets from the various laboratories produces consistent mean number- and volume-weighted core radii of Rn = 2.76 (6) nm and Rv = 3.20 (4) nm, respectively. The corresponding widths of the lognormal radius distribution of the particles were σn = 0.65 (1) nm and σv = 0.71 (1) nm. The particle concentration determined using this method was 3.0 (4) g l-1 or 4.2 (7) × 10-6 mol l-1. These results are affected slightly by the choice of data evaluation procedure, but not by the instruments: the participating laboratories at synchrotron SAXS beamlines, commercial and in-house-designed instruments were all able to provide highly consistent data. This demonstrates that SAXS is a suitable method for revealing particle size distributions in the sub-20 nm region (at minimum), out of reach for most other analytical methods.
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Affiliation(s)
- Brian R Pauw
- Federal Institute for Materials Research and Testing (BAM), Unter den Eichen 87, 12205 Berlin, Germany
| | - Claudia Kästner
- Federal Institute for Materials Research and Testing (BAM), Unter den Eichen 87, 12205 Berlin, Germany
| | - Andreas F Thünemann
- Federal Institute for Materials Research and Testing (BAM), Unter den Eichen 87, 12205 Berlin, Germany
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Marshall J, Allen RA, McGray CD, Geist J. MEMS Young's Modulus and Step Height Measurements With Round Robin Results. J Res Natl Inst Stand Technol 2010; 115:303-342. [PMID: 27134790 PMCID: PMC4548872 DOI: 10.6028/jres.115.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 09/10/2008] [Indexed: 06/05/2023]
Abstract
This paper presents the results of a microelectromechanical systems (MEMS) Young's modulus and step height round robin experiment, completed in April 2009, which compares Young's modulus and step height measurement results at a number of laboratories. The purpose of the round robin was to provide data for the precision and bias statements of two \ related Semiconductor Equipment and Materials International (SEMI) standard test methods for MEMS. The technical basis for the test methods on Young's modulus and step height measurements are also provided in this paper. Using the same test method, the goal of the round robin was to assess the repeatability of measurements at one laboratory, by the same operator, with the same equipment, in the shortest practical period of time as well as the reproducibility of measurements with independent data sets from unique combinations of measurement setups and researchers. Both the repeatability and reproducibility measurements were done on random test structures made of the same homogeneous material. The average repeatability Young's modulus value (as obtained from resonating oxide cantilevers) was 64.2 GPa with 95 % limits of ± 10.3 % and an average combined standard uncertainty value of 3.1 GPa. The average reproducibility Young's modulus value was 62.8 GPa with 95 % limits of ± 11.0 % and an average combined standard uncertainty value of 3.0 GPa. The average repeatability step height value (for a metal2-over-poly1 step from active area to field oxide) was 0.477 μm with 95 % limits of 7.9 % and an average combined standard uncertainty value of 0.014 μm. The average reproducibility step height value was 0.481 μm with 95 % limits of ± 6.2 % and an average combined standard uncertainty value of 0.014 μm. In summary, this paper demonstrates that a reliable methodology can be used to measure Young's modulus and step height. Furthermore, a micro and nano technology (MNT) 5-in-1 standard reference material (SRM) can be used by industry to compare their in-house measurements using this methodology with NIST measurements thereby validating their use of the documentary standards.
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Caskey GW, Phillips SD, Borchardt BR. Results of the NIST National Ball Plate Round Robin. J Res Natl Inst Stand Technol 1997; 102:85-93. [PMID: 27805131 PMCID: PMC4902569 DOI: 10.6028/jres.102.008] [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] [Figures] [Subscribe] [Scholar Register] [Accepted: 10/23/1996] [Indexed: 06/06/2023]
Abstract
This report examines the results of the ball plate round robin administered by NIST. The round robin was part of an effort to assess the current state of industry practices for measurements made using coordinate measuring machines. Measurements of a two-dimensional ball plate (240 mm by 240 mm) on 41 coordinate measuring machines were collected and analyzed. Typically, the deviations of the reported X and Y coordinates from the calibrated values were within ± 5 μm, with some coordinate deviations exceeding 20.0 μm. One of the most significant observations from these data was that over 75 % of the participants failed to correctly estimate their measurement error on one or more of the ball plate spheres.
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Affiliation(s)
- G W Caskey
- National Institute of Standards and Technology, Gaithersburg, MD 20899-0001
| | - S D Phillips
- National Institute of Standards and Technology, Gaithersburg, MD 20899-0001
| | - B R Borchardt
- National Institute of Standards and Technology, Gaithersburg, MD 20899-0001
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Munro RG, Malghan SG, Hsu SM. Variances in the Measurement of Ceramic Powder Properties. J Res Natl Inst Stand Technol 1995; 100:51-60. [PMID: 29151727 PMCID: PMC4887218 DOI: 10.6028/jres.100.005] [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] [Figures] [Subscribe] [Scholar Register] [Accepted: 10/19/1994] [Indexed: 06/07/2023]
Abstract
Variances in the measurement of properties used to characterize ceramic powders are discussed in the context of the International Energy Agency's study, Annex II, Subtask 2, which includes chemical and physical measurements for five powders: two grades of silicon nitride, and one grade each of silicon carbide, silicon, and zirconia. The analysis presented here includes results for 39 properties reported by 25 laboratories using approximately 700 samples of the powders. Measurement uncertainties are discussed in the contexts of measurement variations within given laboratories (within-laboratory variance, sometimes called repeatability), among different laboratories (between-laboratory variance, also called reproducibility), and among different measurement techniques (between-methods variance). The analysis shows that the between-laboratory variance tends to be significantly greater than either the within-laboratory or the between-methods variances. The implication of this result is that the most important improvements in powder characterization measurements may be achieved through the standardization of the measurement methodologies.
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Affiliation(s)
- R G Munro
- National Institute of Standards and Technology, Gaithersburg, MD 20899-0001
| | - S G Malghan
- National Institute of Standards and Technology, Gaithersburg, MD 20899-0001
| | - S M Hsu
- National Institute of Standards and Technology, Gaithersburg, MD 20899-0001
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