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1
Koo, Sangmo. "Advanced Micro-Actuator/Robot Fabrication Using Ultrafast Laser Direct Writing and Its Remote Control." Applied Sciences 10, no. 23 (2020): 8563. http://dx.doi.org/10.3390/app10238563.
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Two-photon polymerization (TPP) based on the femtosecond laser (fs laser) direct writing technique in the realization of high-resolution three-dimensional (3D) shapes is spotlighted as a unique and promising processing technique. It is also interesting that TPP can be applied to various applications in not only optics, chemistry, physics, biomedical engineering, and microfluidics but also micro-robotics systems. Effort has been made to design innovative microscale actuators, and research on how to remotely manipulate actuators is also constantly being conducted. Various manipulation methods have been devised including the magnetic, optical, and acoustic control of microscale actuators, demonstrating the great potential for non-contact and non-invasive control. However, research related to the precise control of microscale actuators is still in the early stages, and in-depth research is needed for the efficient control and diversification of a range of applications. In the future, the combination of the fs laser-based fabrication technique for the precise fabrication of microscale actuators/robots and their manipulation can be established as a next-generation processing method by presenting the possibility of applications to various areas.
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Alapan, Yunus, Oncay Yasa, Berk Yigit, I. Ceren Yasa, Pelin Erkoc, and Metin Sitti. "Microrobotics and Microorganisms: Biohybrid Autonomous Cellular Robots." Annual Review of Control, Robotics, and Autonomous Systems 2, no. 1 (2019): 205–30. http://dx.doi.org/10.1146/annurev-control-053018-023803.
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Biohybrid microrobots, composed of a living organism integrated with an artificial carrier, offer great advantages for the miniaturization of devices with onboard actuation, sensing, and control functionalities and can perform multiple tasks, including manipulation, cargo delivery, and targeting, at nano- and microscales. Over the past decade, various microorganisms and artificial carriers have been integrated to develop unique biohybrid microrobots that can swim or crawl inside the body, in order to overcome the challenges encountered by the current cargo delivery systems. Here, we first focus on the locomotion mechanisms of microorganisms at the microscale, crucial criteria for the selection of biohybrid microrobot components, and the integration of the selected artificial and biological components using various physical and chemical techniques. We then critically review biohybrid microrobots that have been designed and used to perform specific tasks in vivo. Finally, we discuss key challenges, including fabrication efficiency, swarm manipulation, in vivo imaging, and immunogenicity, that should be overcome before biohybrid microrobots transition to clinical use.
3
Tian, Zhenhua, Zeyu Wang, Peiran Zhang, et al. "Generating multifunctional acoustic tweezers in Petri dishes for contactless, precise manipulation of bioparticles." Science Advances 6, no. 37 (2020): eabb0494. http://dx.doi.org/10.1126/sciadv.abb0494.
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Acoustic tweezers are a promising technology for the biocompatible, precise manipulation of delicate bioparticles ranging from nanometer-sized exosomes to millimeter-sized zebrafish larva. However, their widespread usage is hindered by their low compatibility with the workflows in biological laboratories. Here, we present multifunctional acoustic tweezers that can manipulate bioparticles in a disposable Petri dish. Various functionalities including cell patterning, tissue engineering, concentrating particles, translating cells, stimulating cells, and cell lysis are demonstrated. Moreover, leaky surface acoustic wave–based holography is achieved by encoding required phases in electrode profiles of interdigitated transducers. This overcomes the frequency and resolution limits of previous holographic techniques to control three-dimensional acoustic beams in microscale. This study presents a favorable technique for noncontact and label-free manipulation of bioparticles in commonly used Petri dishes. It can be readily adopted by the biological and medical communities for cell studies, tissue generation, and regenerative medicine.
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Paulk, Angelique C., Jimmy C. Yang, Daniel R. Cleary, et al. "Microscale Physiological Events on the Human Cortical Surface." Cerebral Cortex 31, no. 8 (2021): 3678–700. http://dx.doi.org/10.1093/cercor/bhab040.
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Abstract Despite ongoing advances in our understanding of local single-cellular and network-level activity of neuronal populations in the human brain, extraordinarily little is known about their “intermediate” microscale local circuit dynamics. Here, we utilized ultra-high-density microelectrode arrays and a rare opportunity to perform intracranial recordings across multiple cortical areas in human participants to discover three distinct classes of cortical activity that are not locked to ongoing natural brain rhythmic activity. The first included fast waveforms similar to extracellular single-unit activity. The other two types were discrete events with slower waveform dynamics and were found preferentially in upper cortical layers. These second and third types were also observed in rodents, nonhuman primates, and semi-chronic recordings from humans via laminar and Utah array microelectrodes. The rates of all three events were selectively modulated by auditory and electrical stimuli, pharmacological manipulation, and cold saline application and had small causal co-occurrences. These results suggest that the proper combination of high-resolution microelectrodes and analytic techniques can capture neuronal dynamics that lay between somatic action potentials and aggregate population activity. Understanding intermediate microscale dynamics in relation to single-cell and network dynamics may reveal important details about activity in the full cortical circuit.
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Kuo, Hsin Yu, Sunil Vyas, Cheng Hung Chu, et al. "Cubic-Phase Metasurface for Three-Dimensional Optical Manipulation." Nanomaterials 11, no. 7 (2021): 1730. http://dx.doi.org/10.3390/nano11071730.
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The optical tweezer is one of the important techniques for contactless manipulation in biological research to control the motion of tiny objects. For three-dimensional (3D) optical manipulation, shaped light beams have been widely used. Typically, spatial light modulators are used for shaping light fields. However, they suffer from bulky size, narrow operational bandwidth, and limitations of incident polarization states. Here, a cubic-phase dielectric metasurface, composed of GaN circular nanopillars, is designed and fabricated to generate a polarization-independent vertically accelerated two-dimensional (2D) Airy beam in the visible region. The distinctive propagation characteristics of a vertically accelerated 2D Airy beam, including non-diffraction, self-acceleration, and self-healing, are experimentally demonstrated. An optical manipulation system equipped with a cubic-phase metasurface is designed to perform 3D manipulation of microscale particles. Due to the high-intensity gradients and the reciprocal propagation trajectory of Airy beams, particles can be laterally shifted and guided along the axial direction. In addition, the performance of optical trapping is quantitatively evaluated by experimentally measured trapping stiffness. Our metasurface has great potential to shape light for compact systems in the field of physics and biological applications.
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Adam, Georges, Subramanian Chidambaram, Sai Swarup Reddy, Karthik Ramani, and David J. Cappelleri. "Towards a Comprehensive and Robust Micromanipulation System with Force-Sensing and VR Capabilities." Micromachines 12, no. 7 (2021): 784. http://dx.doi.org/10.3390/mi12070784.
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In this modern world, with the increase of complexity of many technologies, especially in the micro and nanoscale, the field of robotic manipulation has tremendously grown. Microrobots and other complex microscale systems are often to laborious to fabricate using standard microfabrication techniques, therefore there is a trend towards fabricating them in parts then assembling them together, mainly using micromanipulation tools. Here, a comprehensive and robust micromanipulation platform is presented, in which four micromanipulators can be used simultaneously to perform complex tasks, providing the user with an intuitive environment. The system utilizes a vision-based force sensor to aid with manipulation tasks and it provides a safe environment for biomanipulation. Lastly, virtual reality (VR) was incorporated into the system, allowing the user to control the probes from a more intuitive standpoint and providing an immersive platform for the future of micromanipulation.
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BRAUN, K. F., F. MORESCO, K. MORGENSTERN, et al. "MANIPULATION OF ATOMS AND MOLECULES FOR CONSTRUCTION OF NANOSYSTEMS: THE SCANNING TUNNELING MICROSCOPE AS AN OPERATIVE TOOL." International Journal of Nanoscience 02, no. 04n05 (2003): 197–218. http://dx.doi.org/10.1142/s0219581x03001218.
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Controlled manipulations with scanning tunneling microscope (STM) down to the scale of small molecules and single atoms allow to build molecular and atomic nanosystems, leading to the fascinating possibility of creating manmade structures on atomic scale. Here we present a short review on investigations based on atomic scale manipulation. Upon soft lateral manipulation of adsorbed species, in which only tip/particle forces are used, three different manipulation modes can be discerned: pushing, pulling and sliding. Even the manipulation of strongly bound native substrate atoms is possible. We demonstrate applications as local analytic and synthetic chemistry tools, with important consequences on surface structure research. Vertical manipulation of Xe and CO leads to improved imaging with functionalized tips. With CO deliberately transferred to the tip, we have also succeeded to perform vibrational spectroscopy on single molecules. Furthermore, we describe how we have reproduced a full chemical reaction with single molecules, whereby all basic steps, namely preparation of the reactants, diffusion and association, are induced with the STM tip. Here also field and electron current effects are employed. Finally, we have extended the manipulation techniques to large specially designed molecules by performing lateral manipulation in constant height and realizing the principle of a conformational molecular switch. Artificial nanoscale structures built in atom by atom fashion can serve as quantum laboratories for investigations of various physical properties.
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Mudrik, Jared M., Michael D. M. Dryden, Nelson M. Lafrenière, and Aaron R. Wheeler. "Strong and small: strong cation-exchange solid-phase extractions using porous polymer monoliths on a digital microfluidic platform." Canadian Journal of Chemistry 92, no. 3 (2014): 179–85. http://dx.doi.org/10.1139/cjc-2013-0506.
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We present the first method for digital microfluidics-based strong cation-exchange solid-phase extractions. Digital microfluidics is a microscale fluid handling technique in which liquid droplets are actuated over an array of electrodes by electrodynamic forces. Strong cation exchange has gained considerable importance in the field of proteomics as a separation mode for protein and peptide extractions. The marriage of these two techniques is achieved by incorporating sulphonate-functionalised porous polymer monolith discs onto digital microfluidic chips. By manipulating sample and solvent droplets onto and off of these porous polymer monoliths, proteins and peptides are extracted by controlling solution pH and ionic strength. This novel microscale extraction method has efficiency comparable to commercially available strong cation-exchange ZipTips and is highly effective for sample cleanup. We anticipate that this digital microfluidic strong cation-exchange extraction technique will prove useful for microscale proteomic analyses and other applications requiring separation of cationic compounds.
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CHEN, WEI-HUNG, JONATHAN D. WILSON, SITHARA S. WIJERATNE, SARAH A. SOUTHMAYD, KUAN-JIUH LIN, and CHING-HWA KIANG. "PRINCIPLES OF SINGLE-MOLECULE MANIPULATION AND ITS APPLICATION IN BIOLOGICAL PHYSICS." International Journal of Modern Physics B 26, no. 13 (2012): 1230006. http://dx.doi.org/10.1142/s021797921230006x.
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Recent advances in nanoscale manipulation and piconewton force detection provide a unique tool for studying the mechanical and thermodynamic properties of biological molecules and complexes at the single-molecule level. Detailed equilibrium and dynamics information on proteins and DNA have been revealed by single-molecule manipulation and force detection techniques. The atomic force microscope (AFM) and optical tweezers have been widely used to quantify the intra- and inter-molecular interactions of many complex biomolecular systems. In this article, we describe the background, analysis, and applications of these novel techniques. Experimental procedures that can serve as a guide for setting up a single-molecule manipulation system using the AFM are also presented.
10
Tang, Zi Rong, M. Rizwan Malik, Tie Lin Shi, J. Gong, L. Nie, and Guang Lan Liao. "Modelling and Fabrication of 3-D Carbon-MEMS for Dielectrophoretic Manipulation of Micro/Nanoparticles in Fluids." Materials Science Forum 628-629 (August 2009): 435–40. http://dx.doi.org/10.4028/www.scientific.net/msf.628-629.435.
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Carbon-MEMS (C-MEMS) have emerged as a new category of devices for micro/nano technology with many potential applications. Dielectrophoretic manipulation of micro/nanoparticles with C-MEMS is studied in this paper. Through electric field distribution modeling in carbon electrode array, we analyze the strongest simulation effect results of electric field in three dimensional (3-D) surface plots depicting the magnitude of electric field in various cross sections at different heights above the channel floor for 2, 10, 30 and 50 μm high carbon electrodes. It is represented here that maximum intensity of electric field generates with the equality between the height above the channel floor and the height of the electrodes. Simulation parameters involved are for dielectrophoretic manipulation of micro/nano particles based on 3-D C-MEMS. The advantages of using 3-D C-MEMS electrodes over other techniques of creating high-throughput systems for dielectrophoretic manipulation environment surrounded by micro/nano horizons are: (i) complex microscale 3-D electrodes with high-aspect ratios can easily be shaped and patterned using conventional lithography (ii) carbon has a high window of stability thus allowing application of higher voltages (iii) there is no need for bulk micromachining or patterning electrodes on multiple planes (iv) the distance between electrodes can precisely be controlled through the lithography process. FEMLAB 3.4 Multiphysics Modeling software (COMSOL, Stockholm, Sweden) is used for the modeling of electric fields and one-layer C-MEMS microelectrode array was fabricated with SU-8 photoresist.
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Desai, A. V., and M. A. Haque. "Test Bed for Mechanical Characterization of Nanowires." Proceedings of the Institution of Mechanical Engineers, Part N: Journal of Nanoengineering and Nanosystems 219, no. 2 (2005): 57–65. http://dx.doi.org/10.1243/17403499jnn42.
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Nanowires are one-dimensional solids that are deemed to be the building-block materials for next-generation sensors and actuators. Owing to their unique length scale, they exhibit superior mechanical properties and other length-scale-dependent phenomena. Most of these are challenging to explore, owing to the difficulties in specimen preparation, manipulation, and the requirement of high-resolution force and displacement sensing. To address these issues, a micromechanical device for uniaxial mechanical testing of single nanowires and nanotubes is used here. The device has 10 nN force and 1 nm displacement resolution and its small size (2 ×1 mm) allows for in situ experimentation inside analytical chambers, such as the electron microscopes. A microscale pick-and-place technique is presented as a generic specimen preparation and manipulation method for testing single nanowires. Preliminary results on zinc oxide nanowires show the Young's modulus and fracture strain to be about 76 GPa and 8 per cent respectively.
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Zhang, Yi, Aaron D. Mickle, Philipp Gutruf, et al. "Battery-free, fully implantable optofluidic cuff system for wireless optogenetic and pharmacological neuromodulation of peripheral nerves." Science Advances 5, no. 7 (2019): eaaw5296. http://dx.doi.org/10.1126/sciadv.aaw5296.
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Studies of the peripheral nervous system rely on controlled manipulation of neuronal function with pharmacologic and/or optogenetic techniques. Traditional hardware for these purposes can cause notable damage to fragile nerve tissues, create irritation at the biotic/abiotic interface, and alter the natural behaviors of animals. Here, we present a wireless, battery-free device that integrates a microscale inorganic light-emitting diode and an ultralow-power microfluidic system with an electrochemical pumping mechanism in a soft platform that can be mounted onto target peripheral nerves for programmed delivery of light and/or pharmacological agents in freely moving animals. Biocompliant designs lead to minimal effects on overall nerve health and function, even with chronic use in vivo. The small size and light weight construction allow for deployment as fully implantable devices in mice. These features create opportunities for studies of the peripheral nervous system outside of the scope of those possible with existing technologies.
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Chu, Po-Yu, Chia-Hsun Hsieh, Chien-Ru Lin, and Min-Hsien Wu. "The Effect of Optically Induced Dielectrophoresis (ODEP)-Based Cell Manipulation in a Microfluidic System on the Properties of Biological Cells." Biosensors 10, no. 6 (2020): 65. http://dx.doi.org/10.3390/bios10060065.
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Cell manipulation using optically induced dielectrophoresis (ODEP) in microfluidic systems has attracted the interest of scientists due to its simplicity. Although this technique has been successfully demonstrated for various applications, one fundamental issue has to be addressed—Whether, the ODEP field affects the native properties of cells. To address this issue, we explored the effect of ODEP electrical conditions on cellular properties. Within the experimental conditions tested, the ODEP-based cell manipulation with the largest velocity occurred at 10 Vpp and 1 MHz, for the two cancer cell types explored. Under this operating condition, however, the cell viability of cancer cells was significantly affected (e.g., 70.5 ± 10.0% and 50.6 ± 9.2% reduction for the PC-3 and SK-BR-3 cancer cells, respectively). Conversely, the exposure of cancer cells to the ODEP electrical conditions of 7–10 Vpp and 3–5 MHz did not significantly alter the cell viability, cell metabolic activity, and the EpCAM, VIM, and ABCC1 gene expression of cancer cells. Overall, this study fundamentally investigated the effect of ODEP electrical conditions on the cellular properties of cancer cells. The information obtained is crucially important for the utilization of ODEP-based cell manipulation in a microscale system for various applications.
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Massee, F., Y. K. Huang, and M. Aprili. "Atomic manipulation of the gap in Bi2Sr2CaCu2O8+x." Science 367, no. 6473 (2020): 68–71. http://dx.doi.org/10.1126/science.aaw7964.
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Single-atom manipulation within doped correlated electron systems could help disentangle the influence of dopants, structural defects, and crystallographic characteristics on local electronic states. Unfortunately, the high diffusion barrier in these materials prevents conventional manipulation techniques. Here, we demonstrate the possibility to reversibly manipulate select sites in the optimally doped high-temperature superconductor Bi2Sr2CaCu2O8+x using the local electric field of the tip of a scanning tunneling microscope. We show that upon shifting individual Bi atoms at the surface, the spectral gap associated with superconductivity is seen to reversibly change by as much as 15 milli–electron volts (on average ~5% of the total gap size). Our toy model, which captures all observed characteristics, suggests that the electric field induces lateral movement of local pairing potentials in the CuO2 plane.
15
Sweet, Walter C. "Scanning electron microscopy and photomicrography." Paleontological Society Special Publications 4 (1989): 351–55. http://dx.doi.org/10.1017/s2475262200005347.
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In the last two decades, scanning electron miocroscopy has come to be the technique of choice in studies of microfossil structure and morphology. Scanning electron microscope (SEM) photomicrographs are easy to produce, have great depth of field, and resolve minute details over a wide range of magnifications. Hence photomicrographs of images produced in a SEM are now more widely used than ordinary photographs in the illustration of microfossils. Techniques for preparation, mounting and manipulation of specimens in the SEM vary with the instrument available, aims of the study, and skill of the operator. Hence attention is directed here primarily to general aspects of SEM technique.
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Warley, Alice. "Electron microscopy: More than just a pretty picture." Biochemist 32, no. 3 (2010): 18–21. http://dx.doi.org/10.1042/bio03203018.
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In the 1990s, it might have been thought that, for biological sciences, electron microscopy (EM) was a technique that had had its day. The majority of cellular ultrastructure had been described, and many EM units were closed. However, new developments in instruments, including computer control of microscope columns and stages, the introduction of digital cameras with freely avail able software for image processing and manipulation and improvements in specimen prepara tion techniques have led to a resurgence in the use of EM and wider applicability in the biological sciences. This article aims to show how, even in its routine use, EM can provide further insight into cell biology studies, to show how EM is being used to provide fundamental information about the localization and relationships of molecules within cells through the technique of immuno cytochemistry and to introduce techniques such as EM tomography that are providing unrivalled information about structure–function relationships within cells.
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Adamovic, Nadja, Ioanna Giouroudi, Jovan Matovic, Zoran Djinovic, and Ulrich Schmid. "Microactuators for Fluidic Applications: Principles, Devices, and Systems." Journal of Microelectronics and Electronic Packaging 6, no. 4 (2009): 250–64. http://dx.doi.org/10.4071/1551-4897-6.4.250.
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Much effort in microfluidics research has been aimed at designing microscale pumps, valves, switches, dispensers, mixers, filters, separators, and so on, which have a major role in the development of innovative systems like chemical process control, bioanalytical devices, medical drug delivery systems, environmental control, and others. Most of these microfluidic devices have one thing in common: the need for precise manipulation and control of small amounts of fluids. MEMS/NEMS research is continuously opening up new knowledge on modeling approaches, novel materials, and MEMS/NEMS processing technologies that stimulate and accelerate the development of new actuation principles and novel actuator configurations. This review paper presents research work on different actuation techniques that are used for the whole range of microfluidic applications. It covers thermomechanical and electrochemical actuation principles, as well as actuation induced with external electric or magnetic fields. It presents a brief explanation of the operating principle of each type of actuator, actuator configuration, its main characteristics, like power consumption, operational voltage, frequency range, and working fluids, and a discussion of comparisons among different actuation schemes. This study compiles and provides some basic guidelines for selection of the actuation schemes that are currently implemented in microfluidic devices.
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Shakya, Subarna. "Automated Nanopackaging using Cellulose Fibers Composition with Feasibility in SEM Environment." June 2021 3, no. 2 (2021): 114–25. http://dx.doi.org/10.36548/jei.2021.2.004.
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By contributing to the system enhancement, the integration of Nano systems for nanosensors with biomaterials proves to be a unique element in the development of novel innovative systems. The techniques by which manipulation, handling, and preparation of the device are accomplished with respect to industrial use are a critical component that must be considered before the system is developed. The approach must be able to be used in a scanning electron microscope (SEM), resistant to environmental changes, and designed to be automated. Based on this deduction, the main objective of this research work is to develop a novel design of Nano electronic parts, which address the issue of packaging at a nanoscale. The proposed research work has used wood fibres and DNA as the bio material to develop nanoscale packaging. The use of a certain atomic force microscope (ATM) for handling DNA in dry circumstances is demonstrated with SCM wood fibrils/fibers manipulation in a scanning electron microscope (SEM).Keywords: Nano electronics, bioelectronics, scanning electron microscope (SEM), packaging, atomic force microscope (ATM)
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XIE, XIAN NING, HONG JING CHUNG, and ANDREW THYE SHEN WEE. "SCANNING PROBE MICROSCOPY BASED NANOSCALE PATTERNING AND FABRICATION." COSMOS 03, no. 01 (2007): 1–21. http://dx.doi.org/10.1142/s0219607707000207.
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Nanotechnology is vital to the fabrication of integrated circuits, memory devices, display units, biochips and biosensors. Scanning probe microscope (SPM) has emerged to be a unique tool for materials structuring and patterning with atomic and molecular resolution. SPM includes scanning tunneling microscopy (STM) and atomic force microscopy (AFM). In this chapter, we selectively discuss the atomic and molecular manipulation capabilities of STM nanolithography. As for AFM nanolithography, we focus on those nanopatterning techniques involving water and/or air when operated in ambient. The typical methods, mechanisms and applications of selected SPM nanolithographic techniques in nanoscale structuring and fabrication are reviewed.
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Koptyug, Andrey, Carlos Botero, William Sjöström, Mikael Bäckström, Lars Erik Rännar, and Anton S. Tremsin. "Electron Beam Melting: From Shape Freedom to Material Properties Control at Macro- and Microscale." Materials Science Forum 1016 (January 2021): 755–61. http://dx.doi.org/10.4028/www.scientific.net/msf.1016.755.
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Electron beam melting (EBM) is one of the constantly developing powder bed fusion (PBF) additive manufacturing technologies (AM) offering advanced control over the manufacturing process. Development of the additive manufacturing today is targeting both widening of the available materials classes, and introducing new manufacturing modalities. Present research is related to the new possibilities in tailoring different properties within additively manufactured components effectively adding “fourth dimension to the 3D-printing”. Through manipulating beam energy deposition (scanning strategy) it is possible to tailor quite different material properties selectively within each manufactured component, including crystalline and amorphous state, effective material density, as well as mechanical, thermal, electrical and acoustic properties. With the blends of precursor powder, it is also possible to acquire by choice both metal-metal composite and completely alloyed material. Specific examples are given in relation to the EBM, but majority of the conclusions are valid for the other PBF techniques as well.
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Ritter, Martin, Didier Henry, Stefan Wiesner, Stephan Pfeiffer, and Roger Wepf. "A Versatile High-Vacuum Cryo-Transfer for Cryo-FESEM, Cryo-SPM and other Imaging Techniques." Microscopy and Microanalysis 5, S2 (1999): 424–25. http://dx.doi.org/10.1017/s1431927600015440.
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A structure preservation of biological and organic samples, close to native state, can only be reached by cryo immobilization techniques. Cryo immobilization allows not only to preserve the high structural integrity but also to arrest dynamic processes in the μs- ms range.After freezing the sample and preparing the surface of interest, it is important to prevent the sample from ice crystal damage, removal of structural water, condensation of water or other contaminants until imaging. Therefore, ideally the samples are kept below the recrystallisation temperature of water (< 147K) during the transfer from the preparation environment into the imaging chamber.For the transfer of frozen samples several concepts have been followed in the,past: a) the specimen after manipulation/preparation were submersed in liquid nitrogen and transferred to the cold stage of the microscope or b) a preparation chamber was permanently attached to the microscope column allowing the direct transfers between the preparation chamber and the cold stage in the microscope. These concepts allow either a high grade of flexibility combined with a high risk of contamination or to prevent contamination but combined with inflexibility. In addition the later also does not allow using the microscope during the specimen preparation procedure, nor transferring the specimen to an other imaging device.
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Janusas, Pilkauskas, Janusas, and Palevicius. "Active PZT Composite Microfluidic Channel for Bioparticle Manipulation." Sensors 19, no. 9 (2019): 2020. http://dx.doi.org/10.3390/s19092020.
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The concept of active microchannel for precise manipulation of particles in biomedicine is reported in this paper. A novel vibration-assisted thermal imprint method is proposed for effective formation of a microchannel network in the nanocomposite piezo polymer layer. In this method, bulk acoustic waves of different wavelengths excited in an imprinted microstructure enable it to function in trapping–patterning, valve, or free particle passing modes. Acoustic waves are excited using a special pattern of electrodes formed on its top surface and a single electric ground electrode formed on the bottom surface. To develop the microchannel, we first started with lead zirconate titanate (PZT) nanopowder [Pb (Zrx, Ti1–x) O3] synthesis. The PZT was further mixed with three different binding materials—polyvinyl butyral (PVB), poly(methyl methacrylate) (PMMA), and polystyrene (PS)—in benzyl alcohol to prepare a screen-printing paste. Then, using conventional screen printing techniques, three types of PZT coatings on copper foil substrates were obtained. To improve the voltage characteristics, the coatings were polarized. Their structural and chemical composition was analyzed using scanning electron microscope (SEM), while the mechanical and electrical characteristics were determined using the COMSOL Multiphysics model with experimentally obtained parameters of periodic response of the layered copper foil structure. The hydrophobic properties of the PZT composite were analyzed by measuring the contact angle between the distilled water drop and the three different polymer composites: PZT with PVB, PZT with PMMA, and PZT with PS. Finally, the behavior of the microchannel formed in the nanocomposite piezo polymer was simulated by applying electrical excitation signal on the pattern of electrodes and then analyzed experimentally using holographic interferometry. Wave-shaped vibration forms of the microchannel were obtained, thereby enabling particle manipulation.
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Chang, Ming, Po Cheng Chen, Chung Po Lin, and Yu Han Chang. "Assembly of Nanostructures by Using a Mechanical Nanomanipulator." Key Engineering Materials 450 (November 2010): 263–66. http://dx.doi.org/10.4028/www.scientific.net/kem.450.263.
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A mechanical nanomanipulation system has been developed for the assembly and fabrication of nano-devices inside a scanning electron microscope (SEM). The mechanical manipulator is made up of commercially available actuators and positioning stages which consists of three individual operation units each having three linear stages and one rotational stage. Experiments were performed to construct 2D and 3D nanostructures with Au nanowires. Versatile manipulations including shape modification, length amendment, and connection of nanowires were carried out. An electron beam induced deposition (EBID) technique was used to grasp nano-materials and assemble them, enabling 2D and 3D manipulation to be easier to conduct. Experimental results show that this manipulator is possible to play an important role in enabling the technology of assembling nano-scale mechanical and electronic devices from prefabricated nano-scale components.
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Lu, Xiwen, Jinhang Liu, Ye Ding, Lijun Yang, Zhan Yang, and Yang Wang. "Simulation and fabrication of carbon nanotube–nanoparticle interconnected structures." Mechanical Sciences 12, no. 1 (2021): 451–59. http://dx.doi.org/10.5194/ms-12-451-2021.
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Abstract. With the rapid development of nanotechnology, the size of a device reaches sub-nanometer scale. The larger resistivity of interconnect leads to serious overheating of integrated circuits. Silicon-based electronic devices have also reached the physical limits of their development. The use of carbon nanotubes instead of traditional wires has become a new solution for connecting nano-structures. Nanocluster particles serving as brazing material play an important role in stabilizing the connection of carbon nanotubes, which places higher demands for nanoscale manipulation techniques. In this paper, the dynamic processes under different operating scenarios were simulated and analyzed, including probe propulsion nanoparticle operation, probe pickup nanoparticle operation and probe pickup nanocluster particle operation. Then, the SEM (Scanning Electron Microscope) was used for nanoparticle manipulation experiments. The smallest unit of carbon nanotube wire was obtained by three-dimensional (3D) construction of a carbon nanotube–silver nanocluster particle (CN-AgNP), which verified the feasibility of 3D manipulation of carbon nanotube wire construction. The experiments on the construction of carbon nanotube–nanocluster particle structures in three-dimensional operation were completed, and the smallest unit of carbon nanotube wire was constructed. This nano-fabrication technology will provide an efficient and mature technical means in the field of nano-interconnection.
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Maxfield, Frederick R. "Characterization of endocytosis in intact cells by quantitative fluorescence microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 49 (August 1991): 234–35. http://dx.doi.org/10.1017/s0424820100085472.
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Endocytosis, the process by which extracellular macromolecules are taken into the cell is particularly amenable to quantitative analysis using fluorescence techniques. Fluorescently-labeled proteins and other macromolecules are taken up by cells via receptor-mediated endocytosis or fluid phase pinocytosis. Recently, fluorescent lipid probes have also been synthesized which label the endocytic pathway, allowing observation of lipid membrane traffic.Digital imaging allows the manipulation of images, background and autofluorescence subtractions, and fluorescence intensity measurements of individual endocytic compartments. Image intensification microscopy and digital image processing have been used extensively for studies of endocytosis, including the measurements of endosome pH, and the identification and quantitation of endocytic vesicle fusion. Recently, pathways taken by endocytosed fluorescent molecules have been followed using the confocal microscope, adding a powerful tool to investigate questions about endocytosis which were very difficult to study with conventional, full-field microscopy techniques.
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Li, Changhai, Fengqiang Zhang, Jia Zhang, Bin Guo, and Zhenlong Wang. "A Universal Solution of Controlling the Distribution of Multimaterials during Macroscopic Manipulation via a Microtopography-Guided Substrate." Nanomaterials 8, no. 12 (2018): 1036. http://dx.doi.org/10.3390/nano8121036.
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Any object can be considered as a spatial distribution of atoms and molecules; in this sense, we can manufacture any object as long as the precise distribution of atoms and molecules is achieved. However, the current point-by-point methods to precisely manipulate single atoms and single molecules, such as the scanning tunneling microscope (STM), have difficulty in manipulating a large quantity of materials within an acceptable time. The macroscopic manipulation techniques, such as magnetron sputtering, molecular beam epitaxy, and evaporation, could not precisely control the distribution of materials. Herein, we take a step back and present a universal method of controlling the distribution of multimaterails during macroscopic manipulation via microtopography-guided substrates. For any given target distribution of multimaterials in a plane, the complicated lateral distribution of multimaterials was firstly transformed into a simple spatial lamellar body. Then, a deposition mathematical model was first established based on a mathematical transformation. Meanwhile, the microtopographic substrate can be fabricated according to target distribution based on the deposition mathematical model. Following this, the deposition was implemented on the substrate according to the designed sequence and thickness of each material, resulting in the formation of the deposition body on the substrate. Finally, the actual distribution was obtained on a certain section in the deposition body by removing the upside materials. The actual distribution can mimic the target one with a controllable accuracy. Furthermore, two experiments were performed to validate our method. As a result, we provide a feasible and scalable solution for controlling the distribution of multimaterials, and point out the direction of improving the position accuracy of each material. We may achieve real molecular manufacturing and nano-manufacturing if the position accuracy of distribution approaches the atomic level.
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Perez, Hector, Qingze Zou, and Santosh Devasia. "Design and Control of Optimal Scan Trajectories: Scanning Tunneling Microscope Example." Journal of Dynamic Systems, Measurement, and Control 126, no. 1 (2004): 187–97. http://dx.doi.org/10.1115/1.1636770.
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This article addresses the optimal (minimal input energy) design of scan trajectories, which is important in applications such as the imaging and manipulation of nano-scale surface phenomena using scanning tunneling microscopes (STM), MEMS-based micro-scanners, quick-return mechanisms and cams used in manufacturing, and general repeating processes. The contribution of this article is the systematic solution of the optimal scan-trajectory design problem. As opposed to existing techniques that require pre-specification of the desired output trajectory (such prespecifications can be ad hoc), the optimal output trajectory is found as a result of the proposed input-energy minimization approach. In this sense, the proposed approach leads to a systematic solution of the optimal output-trajectory-design problem. The proposed optimal scanning method is applied to an experimental scanning tunneling microscope; simulation and experimental results are presented to illustrate the efficacy of the proposed approach to design optimal scan-trajectories.
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Suh, Yong J., Sergey V. Prikhodko, and Sheldon K. Friedlander. "Nanostructure Manipulation Device for Transmission Electron Microscopy: Application to Titania Nanoparticle Chain Aggregates." Microscopy and Microanalysis 8, no. 6 (2002): 497–501. http://dx.doi.org/10.1017/s1431927602010437.
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Experimental difficulties in studying nanostructures stem from their small size, which limits the use of traditional techniques for measuring their physical properties. We have developed a nanostructure manipulation device to apply tension to chain aggregates mounted in a transmission electron microscope. A 1-mm-long slit was cut in the center of a lead–tin alloy disc, measuring 3 mm in diameter and 200 μm in thickness. The disc was heated to about 140°C before it was pressed between two quartz slides. The disc was then thinned by mechanical dimpling and ion milling until holes developed around the slit. The edges of the slit were 0.2 to 3 μm in thickness while the gap between them was up to a few microns. This disc was bonded to the two plates of a cartridge. The slit could be widened or narrowed at controlled speeds of 0.5 to 300 nm/s. The system was tested using titania (TiO2) nanoparticle chain aggregates (NCA) deposited across the slit. The ends of the NCA remained attached to the edges of the slit, which was widened at about 0.7 nm/s. In this way, the NCA was stretched up to 176% of its initial length before breaking.
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Johnstone, Graeme E., Gemma S. Cairns, and Brian R. Patton. "Nanodiamonds enable adaptive-optics enhanced, super-resolution, two-photon excitation microscopy." Royal Society Open Science 6, no. 7 (2019): 190589. http://dx.doi.org/10.1098/rsos.190589.
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Particles of diamond in the 5–100 nm size range, known as nanodiamond (ND), have shown promise as robust fluorophores for optical imaging. We demonstrate here that, due to their photostability, they are not only suitable for two-photon imaging, but also allow significant resolution enhancement when combined with computational super-resolution techniques. We observe a resolution of 42.5 nm when processing two-photon images with the Super-Resolution Radial Fluctuations algorithm. We show manipulation of the point-spread function of the microscope using adaptive optics. This demonstrates how the photostability of ND can also be of use when characterizing adaptive optics technologies or testing the resilience of super-resolution or aberration correction algorithms.
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Zhang, Zhuoran, Xian Wang, Jun Liu, Changsheng Dai, and Yu Sun. "Robotic Micromanipulation: Fundamentals and Applications." Annual Review of Control, Robotics, and Autonomous Systems 2, no. 1 (2019): 181–203. http://dx.doi.org/10.1146/annurev-control-053018-023755.
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Robotic micromanipulation is a relatively young field. However, after three decades of development and evolution, the fundamental physics; techniques for sensing, actuation, and control; tool sets and systems; and, more importantly, a research community are now in place. This article reviews the fundamentals of robotic micromanipulation, including how micromanipulators and end effectors are actuated and controlled, how remote physical fields are utilized for micromanipulation, how visual servoing is implemented under an optical microscope, how force is sensed and controlled at the micro- and nanonewton levels, and the similarities and differences between robotic manipulation at the micro- and macroscales. We also review representative milestones over the past three decades and discuss potential future trends of this field.
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Shoeb, Mohammed, Vinod Gite, Samir Bhargava, and Shashikant Mhashal. "Comparison of surgical outcomes of tympanoplasty assisted by conventional microscopic method and endoscopic method." International Journal of Otorhinolaryngology and Head and Neck Surgery 2, no. 4 (2016): 184. http://dx.doi.org/10.18203/issn.2454-5929.ijohns20163166.
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<p class="abstract"><strong>Background:</strong> The introduction of the operating microscope has significantly enhanced the outcome of tympanoplasty by improving the accuracy of the technique. The operating microscopy provides a magnified image in straight line; hence the surgeon can’t visualize the deep recesses of the middle ear in single operating field. This is overcome by use of rigid endoscope for tympanoplasty. In rigid endoscopy view is better but surgeons 2 hands are not free so manipulation here is difficult.</p><p class="abstract"><strong>Methods:</strong> 30 cases of safe CSOM from each group viz microscopic assisted (MES) &amp; endoscopic assisted (EES) were selected operated by full cuff (superiorly based tympanomeatal flap technique) and compared for graft uptake, hearing improvement &amp; complications.</p><p class="abstract"><strong>Results:</strong> Graft uptake rate was 93.33% in both groups. In our study the pre operative mean air bone gap of the patients was 37.23+5.79 db after surgery at 6 months came down to 17.17+3.31 db hence after calculating the mean air bone gap closure it came down to be 20.4+4.85. Which showed a significant improvement in the hearing (p value 1.493E-23 which is less than 0.05). 6.67% cases from both groups showed failure of graft uptake.</p><p><strong>Conclusions:</strong> The graft uptake, hearing improvement, Complications produced by each of the techniques in large, subtotal, and anterior moderate perforations by each technique is comparable i.e. both techniques have same results.</p>
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Koebbe, Christopher J., Joseph C. Maroon, Adnan Abla, Hikmat El-Kadi, and Jeffery Bost. "Lumbar microdiscectomy: a historical perspective and current technical considerations." Neurosurgical Focus 13, no. 2 (2002): 1–6. http://dx.doi.org/10.3171/foc.2002.13.2.4.
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A historical review is presented of the original descriptions of lumbar discectomy, focusing on the evolution toward a less invasive surgical approach following the introduction of the operating microscope. From the initial work in Europe by Yaşargil and Caspar to the popularization of microdiscectomy by Williams and Wilson in the United States, this procedure has successfully reduced operative time, surgical morbidity, and incision size while allowing patients to return to work faster. Emphasis is placed on the importance of a careful preoperative clinical and radiographic evaluation by identifying factors that may help in the prediction of a successful surgical outcome. A modification of the lumbar microdiscectomy technique is described including patient positioning in the lateral position as well as minimal disc space and nerve root manipulation. In their experience performing more than 3000 microdiscectomies, the authors have produced good-to-excellent clinical results in nearly 90% of patients, with the majority returning to work within 1 month. The complication rate of dural tears, discitis, or root injury has been less than 2%, with a reoperation rate of 5%. The authors believe that lumbar microdiscectomy remains the gold standard with which all other discectomy techniques must be compared.
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Berdan, Jean M. "Mechanical extraction of microfossils." Paleontological Society Special Publications 4 (1989): 99–100. http://dx.doi.org/10.1017/s2475262200005037.
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The described techniques for extraction of microfossils are directed primarily at the extraction of calcareous microfossils from various types of limestone, although the same techniques may beused for some sandstones and shales. The equipment needed is not complicated; the most obvious is a good binocular microscope with a working distance of three or more inches, to allow manipulation of the rock from which the specimens are to be extracted. The magnification required depends on the size of the specimens, but should go up to at least 80x. Other essential tools are a pin vise with a chuck which will hold an ordinary steel sewing needle and a rotary dental machine or other grinding device which will accept a small thin carborundum wheel. The latter is useful for sharpening needles as well as for cutting specimens out of the rock. An additional useful item is a percussive device such as a mechanical engraver fitted with a chuck which will hold an old fashioned steel phonograph needle. This instrument is described in detail by Palmer (this volume, chapter 20). A dish of water and a fine (00000) camel's hairbrush are necessary to move the specimens, once freed, to a slide or other receptacle. A rock trimmer is useful for reducing large blocks of fossiliferous rock into pieces that can be handled under the microscope, although with some collections this can be done with a hammer and cold chisel. Some paleontologists prefer to crush their samples and then pick through the chips to find specimens; however, this technique tends to break spines and frills from highly ornamented forms and is not recommended unless the microfauna is known to consist mostly of smooth species. Most of the equipment mentioned above can be found in catalogs such as that of the Edmund Scientific Co., 101 E. Gloucester Pike, Barrington, N.J. 08007.
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Evzikov, G. Yu, M. G. Bashlachev, A. V. Farafontov, S. S. Nikitin, and F. V. Grebenev. "Intraneural ganglion of the peroneal nerve: a report of 3 cases and literature review." Russian journal of neurosurgery 21, no. 4 (2019): 89–96. http://dx.doi.org/10.17650/1683-3295-2019-21-4-89-96.
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The objective is to report 3 cases of intraneural cyst (ganglion) of the peroneal nerve and compare our own findings with the data from scientific literature.Case reports. Three patients with intraneural ganglions of the common peroneal nerve were treated in the Department of Neurosurgery, A.Ya. Kozhevnikov Clinic of Nervous Diseases, I.M. Sechenov First Moscow State Medical University between 2013 and 2019. All patients underwent extensive dissection of the cyst wall, evacuation of secretion; 2 of them had ligation of the articular nerve branch, while in one patient, the articular branch was not revealed. Complete nerve recovery was registered in all cases.Conclusion. We believe that ganglion dissection using microsurgical techniques with surgical microscope is a safe and noncomplex procedure; therefore, the avoidance of this manipulation seems unjustified.Conflict of interest. The authors declare no conflict of interest.Informed consent. All patients gave written informed consent to the publication of their data.
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Kazmaier, Peter, and Naveen Chopra. "Bridging Size Scales with Self-Assembling Supramolecular Materials." MRS Bulletin 25, no. 4 (2000): 30–35. http://dx.doi.org/10.1557/mrs2000.26.
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The notion of micromachines made up of miniature gears and motors may seem like a fairy tale. In 1959, Richard Feynman delivered a lecture entitled “There's Plenty of Room at the Bottom,” a bold prediction of what was to come in the future, where one could fit the entire Encyclopaedia Britannica onto the head of a pin or use ions focused through a microscope lens in reverse to etch away silica to create patterns on a submicron scale. In retrospect, Feynman's hypotheses were amazingly accurate. He was describing the techniques of microlithography and the manipulation of atoms by scanning tunneling electron microscopy, methods that are commonplace today. Advances in biochemistry have revealed the enormous complexity of “simple” organisms, leading one to conclude that “micromachines” (of a complexity that a visionary giant such as Feynman had foreseen) have long been operating quite happily without any assistance from chemists!
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Tutino, Marco, and Matteo Merlo. "Accounting fraud: A literature review." Risk Governance and Control: Financial Markets and Institutions 9, no. 1 (2019): 8–25. http://dx.doi.org/10.22495/rgcv9i1p1.
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This paper explains the main features of accounting fraud across an examination of the current literature by putting the environment and the different ways to prevent fraud under a microscope. The study analyses in five steps how corporate governance, ethical behaviour, accounting manipulation, detection techniques and forensic accounting are related to fraud. After having reviewed the most relevant literature on the topic, it emerged that in order to avoid fraudulent behaviour in a company, it is important, mostly, to establish an ethical education between employees and executives. Therefore, this article examines how governance elements such as board, CEO, or remuneration, influence the occurrence of fraud inside companies. Last but not at least, it has been seen how the role of forensic accountant has revealed itself as being very useful for his varied expertise, which have been analysed, and has been positioned as one of the top 20 future jobs.
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Kanyó, Katalin, J. Konc, L. Solti, and S. Cseh. "Assisted reproductive research: Laser assisted hatching and spindle detection (spindle view technique)." Acta Veterinaria Hungarica 52, no. 1 (2004): 113–23. http://dx.doi.org/10.1556/avet.52.2004.1.11.
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Animal experiments are very important for the development of new assisted reproductive techniques (ART) for use in human and animal reproductive medicine. Most technical aspects of reproductive manipulation of humans and animals are very similar, and many components of successful human ART used nowadays have been derived from animal studies. In this study we examined (1) the use of 'non-contact' laser for assisted hatching, (2) whether spindles in living mouse oocytes could safely be imaged/examined by polarisation microscope (polscope) and (3) the influence of environment (e.g. temperature, in vitro culture, etc.) on spindle detection/visualisation. The data of the study presented here show that (1) laser assisted hatching (AH) is a fast, very accurate and safe procedure without any harmful effect on embryo development and it can support very effectively the implantation of embryos, (2) the use of polscope facilitates the evaluation of oocyte quality and the selection of oocytes with spindle, (3) by monitoring the spindle position during intracytoplasmic sperm injection (ICSI), we can reduce spindle damage and increase the chance of fertilisation. Further studies are underway to test the hypothesised connection between spindle birefringence and developmental capacity of oocytes/embryos.
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Droppo, Ian G., Derrick T. Flannigan, Gary G. Leppard, and Steven N. Liss. "Microbial floc stabilization and preparation for structural analysis by correlative microscopy." Water Science and Technology 34, no. 5-6 (1996): 155–62. http://dx.doi.org/10.2166/wst.1996.0547.
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In the analysis of microbial flocs from activated sludge it is important to stabilize these structures and their components for structural studies sufficiently to assess, minimize and conceptually balance artifacts, particularly during manipulation. By employing multi-technique stabilization and immediate preservation it is possible to analyze a single sample by correlative microscopy (conventional optical microscopy (COM), scanning confocal laser microscopy (SCLM), and transmission electron microscopy (TEM)). This approach minimizes variability associated with multiple sampling. Floc samples were collected using plankton chambers consisting of reservoirs with a removable circular microscope slide. Flocs which come to rest on the slide are stabilized within low melting point agarose. The solidified gel is a clear, highly porous and resilient medium amenable to further staining, washing, sub-sampling or direct microscopic analysis. Stabilization in agarose was found not to significantly influence floc size distribution. The use of agarose was found to be compatible with SCLM and TEM techniques and minimized perturbations. Agar-embedded samples were easily infused with Nanoplast, a hydrophilic melamine resin, which stabilizes material in its natural state. This facilitates the ultrastructural analysis of the three-dimensional fibrillar architecture of the floc matrix. The matrix is found to consist of complex pores bounded by fibrils of 4-6 nm diameter.
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Wen, Hongjing, Bin Wang, Hongbo Zhu, et al. "Security-Enhanced 3D Data Encryption Using a Degradable pH-Responsive Hydrogel." Nanomaterials 11, no. 7 (2021): 1744. http://dx.doi.org/10.3390/nano11071744.
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Based on degradable pH-responsive hydrogel, we report on an enhanced three-dimensional data encryption security technique in which a pH value is used for information manipulation. Featuring three types of states upon the pH value variation, namely, shrinkage, expansion and degradation, the hydrogel renders a limited pH value window as the “key” for information decryption. The pH-dependent shrinkage-to-expansion conversion of the hydrogel leads to a threshold pH value for retrieving the recorded data, whilst the degradability of the hydrogel, which can be tuned by adjusting the composition ratio of PEGDA/AAc, gives rise to a second threshold pH value for irreversibly sabotaging the retrieved data. Pre-doping silver ions in the hydrogel facilitates explicit recording and reading of binary data in forms of three-dimensional silver patterns through photoreduction and scattering, respectively, with a femtosecond laser. By accurately matching the vertical spacing of the encoded silver nanopatterns with the diffraction-limited focal depth of the decryption microscope, we can tune the pH value to encrypt and retrieve information recorded in layers and set a critical pH value to smash encoded information, which proves a highly secured 3D data encoding protocol. This strategy can effectively enrich data encryption techniques, vastly enhancing data security within unattained chemical dimensions.
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Rovó, László, Ádám Bach, László Szakács, Zsolt Bella, and György Lázár. "Módosított Weerda-laringoszkópok alkalmazási területei a fül-orr-gégészeti gyakorlatban." Orvosi Hetilap 160, no. 7 (2019): 264–69. http://dx.doi.org/10.1556/650.2019.31278.
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Abstract: Microscope-assisted direct endoscopy of the airways and the upper gastrointestinal tract in general anesthesia is an essential diagnostic and therapeutic method of otorhinolaryngology. The quality of surgical exploration is a key for the good visibility and maneuverability of microsurgical tools. Beside the most commonly used Kleinsasser laryngoscope, the distending Weerda laryngoscope is a more favorable option for the exploration of the retrocricoid region. Narrow anatomical situation, examination and manipulation of lesions involving several sub-regions of the hypopharynx or larynx may be problematic in some cases even with this endoscope. The authors present the application of modified Weerda laryngoscopes with asymmetric spatula length in addition with four cases. The retrocricoid region, the distal part of the posterior hypopharyngeal wall and the proximal part of the esophagus can be easily visualized with this device. The modifications allow the introduction of new surgical techniques by increasing the number of applied microsurgical devices and their maneuverability. Orv Hetil. 2019; 160(7): 264–269.
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Barber, Samuel R., Saurabh Jain, Michael A. Mooney, et al. "Combining Stereoscopic Video and Virtual Reality Simulation to Maximize Education in Lateral Skull Base Surgery." Otolaryngology–Head and Neck Surgery 162, no. 6 (2020): 922–25. http://dx.doi.org/10.1177/0194599820907866.
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Mastery of lateral skull base (LSB) surgery requires thorough knowledge of complex, 3-dimensional (3D) microanatomy and techniques. While supervised operation under binocular microscopy remains the training gold standard, concerns over operative time and patient safety often limit novice surgeons’ stereoscopic exposure. Furthermore, most alternative educational resources cannot meet this need. Here we present proof of concept for a tool that combines 3D-operative video with an interactive, stereotactic teaching environment. Stereoscopic video was recorded with a microscope during translabyrinthine approaches for vestibular schwannoma. Digital imaging and communications in medicine (DICOM) temporal bone computed tomography images were segmented using 3D-Slicer. Files were rendered using a game engine software built for desktop virtual reality. The resulting simulation was an interactive immersion combining a 3D operative perspective from the lead surgeon’s chair with virtual reality temporal bone models capable of hands-on manipulation, label toggling, and transparency modification. This novel tool may alter LSB training paradigms.
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Zhang, Shuailong, Erica Y. Scott, Jastaranpreet Singh, et al. "The optoelectronic microrobot: A versatile toolbox for micromanipulation." Proceedings of the National Academy of Sciences 116, no. 30 (2019): 14823–28. http://dx.doi.org/10.1073/pnas.1903406116.
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Microrobotics extends the reach of human-controlled machines to submillimeter dimensions. We introduce a microrobot that relies on optoelectronic tweezers (OET) that is straightforward to manufacture, can take nearly any desirable shape or form, and can be programmed to carry out sophisticated, multiaxis operations. One particularly useful program is a serial combination of “load,” “transport,” and “deliver,” which can be applied to manipulate a wide range of micrometer-dimension payloads. Importantly, microrobots programmed in this manner are much gentler on fragile mammalian cells than conventional OET techniques. The microrobotic system described here was demonstrated to be useful for single-cell isolation, clonal expansion, RNA sequencing, manipulation within enclosed systems, controlling cell–cell interactions, and isolating precious microtissues from heterogeneous mixtures. We propose that the optoelectronic microrobotic system, which can be implemented using a microscope and consumer-grade optical projector, will be useful for a wide range of applications in the life sciences and beyond.
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Genuzio, Francesca, Tomasz Giela, Matteo Lucian, et al. "A UHV MOKE magnetometer complementing XMCD-PEEM at the Elettra Synchrotron." Journal of Synchrotron Radiation 28, no. 3 (2021): 995–1005. http://dx.doi.org/10.1107/s1600577521002885.
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We report on a custom-built UHV-compatible Magneto-Optical Kerr Effect (MOKE) magnetometer for applications in surface and materials sciences, operating in tandem with the PhotoEmission Electron Microscope (PEEM) endstation at the Nanospectroscopy beamline of the Elettra synchrotron. The magnetometer features a liquid-nitrogen-cooled electromagnet that is fully compatible with UHV operation and produces magnetic fields up to about 140 mT at the sample. Longitudinal and polar MOKE measurement geometries are realized. The magneto-optical detection is based on polarization analysis using a photoelastic modulator. The sample manipulation system is fully compatible with that of the PEEM, making it possible to exchange samples with the beamline endstation, where complementary X-ray imaging and spectroscopy techniques are available. The magnetometer performance is illustrated by experiments on cobalt ultra-thin films, demonstrating close to monolayer sensitivity. The advantages of combining in situ growth, X-ray Magnetic Circular Dichroism imaging (XMCD-PEEM) and MOKE magnetometry into a versatile multitechnique facility are highlighted.
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Oishi, Makoto, Masafumi Fukuda, Naoki Yajima, et al. "Interactive presurgical simulation applying advanced 3D imaging and modeling techniques for skull base and deep tumors." Journal of Neurosurgery 119, no. 1 (2013): 94–105. http://dx.doi.org/10.3171/2013.3.jns121109.
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Object In this paper, the authors' goal was to report their novel presurgical simulation method applying interactive virtual simulation (IVS) using 3D computer graphics (CG) data and microscopic observation of color-printed plaster models based on these CG data in surgery for skull base and deep tumors. Methods For 25 operations in 23 patients with skull base or deep intracranial tumors (meningiomas, schwannomas, epidermoid tumors, chordomas, and others), the authors carried out presurgical simulation based on 3D CG data created by image analysis for radiological data. Interactive virtual simulation was performed by modifying the 3D CG data to imitate various surgical procedures, such as bone drilling, brain retraction, and tumor removal, with manipulation of a haptic device. The authors also produced color-printed plaster models of modified 3D CG data by a selective laser sintering method and observed them under the operative microscope. Results In all patients, IVS provided detailed and realistic surgical perspectives of sufficient quality, thereby allowing surgeons to determine an appropriate and feasible surgical approach. Surgeons agreed that in 44% of the 25 operations IVS showed high utility (as indicated by a rating of “prominent”) in comprehending 3D microsurgical anatomies for which reconstruction using only 2D images was complicated. Microscopic observation of color-printed plaster models in 12 patients provided further utility in confirming realistic surgical anatomies. Conclusions The authors' presurgical simulation method applying advanced 3D imaging and modeling techniques provided a realistic environment for practicing microsurgical procedures virtually and enabled the authors to ascertain complex microsurgical anatomy, to determine the optimal surgical strategies, and also to efficiently educate neurosurgical trainees, especially during surgery for skull base and deep tumors.
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Voldman, Joel. "ELECTRICAL FORCES FOR MICROSCALE CELL MANIPULATION." Annual Review of Biomedical Engineering 8, no. 1 (2006): 425–54. http://dx.doi.org/10.1146/annurev.bioeng.8.061505.095739.
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Muniz-Junqueira, Maria Imaculada, Lídia Maria Figueira Peçanha, Valeriano Luiz da Silva-Filho, Maria Cecília de Almeida Cardoso, and Carlos Eduardo Tosta. "Novel Microtechnique for Assessment of Postnatal Maturation of the Phagocytic Function of Neutrophils and Monocytes." Clinical Diagnostic Laboratory Immunology 10, no. 6 (2003): 1096–102. http://dx.doi.org/10.1128/cdli.10.6.1096-1102.2003.
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ABSTRACT We describe a simple test for the evaluation of phagocytosis and provide a chart of reference values to evaluate normal phagocytosis by age. We assessed the postnatal maturation of phagocytic function of neutrophils and monocytes. Phagocytosis was evaluated in newborn children delivered vaginally or by cesarean section, infants, preschool children, schoolchildren, and adult subjects. Two drops of blood were placed on a microscope slide and incubated with Saccharomyces cerevisiae yeasts, and phagocytosis was evaluated by microscopy. Our technique showed results comparable to or better than those obtained by other usual techniques. The neutrophils of newborn children delivered by cesarean section showed a phagocytic capacity 45% higher than those of neonates delivered vaginally, whereas neutrophils from children in the latter group showed the lowest phagocytic capacity of all age groups. Phagocytosis by neutrophils reached the levels seen in adults at about the first year of life, while there were no important variations in phagocytosis by monocytes in the different age groups. The technique described is reliable and fast, uses only a few drops of blood, and allows better preservation of cell function due to the minimal manipulation to which the cells are submitted. The delayed maturation of the phagocytic function by neutrophils may account for the high levels of susceptibility of newborn and infant children to bacterial infections. This practical method of assessment of phagocytosis may allow the diagnosis of primary or secondary phagocytic deficiencies to be made more easily and may allow better monitoring and treatment of those with dysfunctions of these cells.
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Sato, Masahiko, Janice Herring, John Kim, and Eli Lilly. "Reflected polarized darkfield imaging of bone surfaces." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 2 (1992): 956–57. http://dx.doi.org/10.1017/s0424820100129413.
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Reflected polarized light microscopy (Fig. 1A) was used previously to generate high contrast images of birefringent and light scattering samples, including bone surfaces and autoradiographic specimens. We now present a modification (Fig. 1B) of the Gullberg system with improved sensitivity for the characterization of bone specimens and quantitation of silver granules on autoradiographic specimens. Reflected imaging techniques were useful to generate high contrast images superior to transmitted light strategies, and both of the strategies presented can be adapted easily to any fluorescence microscope.Reflected light produced images free of refractile noise from materials through the thickness of the specimen which detracts from transmission darkfield imaging of silver grains and brightfield imaging of bone surfaces. The use of crossed polars also eliminated noise from stray light reflected off of internal microscope elements. The rotatable lambda/4 plate mounted on the objective front element (Fig. 1A) allowed considerable manipulation of image contrast, permitting dual imaging of silver granules, birefringent tissues in autoradiographic specimens and the surface topography of bone specimens by rotating the lambda/4 plate to 45°.
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Leinen, Philipp, Matthew F. B. Green, Taner Esat, Christian Wagner, F. Stefan Tautz, and Ruslan Temirov. "Virtual reality visual feedback for hand-controlled scanning probe microscopy manipulation of single molecules." Beilstein Journal of Nanotechnology 6 (November 16, 2015): 2148–53. http://dx.doi.org/10.3762/bjnano.6.220.
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Controlled manipulation of single molecules is an important step towards the fabrication of single molecule devices and nanoscale molecular machines. Currently, scanning probe microscopy (SPM) is the only technique that facilitates direct imaging and manipulations of nanometer-sized molecular compounds on surfaces. The technique of hand-controlled manipulation (HCM) introduced recently in Beilstein J. Nanotechnol. 2014, 5, 1926–1932 simplifies the identification of successful manipulation protocols in situations when the interaction pattern of the manipulated molecule with its environment is not fully known. Here we present a further technical development that substantially improves the effectiveness of HCM. By adding Oculus Rift virtual reality goggles to our HCM set-up we provide the experimentalist with 3D visual feedback that displays the currently executed trajectory and the position of the SPM tip during manipulation in real time, while simultaneously plotting the experimentally measured frequency shift (Δf) of the non-contact atomic force microscope (NC-AFM) tuning fork sensor as well as the magnitude of the electric current (I) flowing between the tip and the surface. The advantages of the set-up are demonstrated by applying it to the model problem of the extraction of an individual PTCDA molecule from its hydrogen-bonded monolayer grown on Ag(111) surface.
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Dalir, Hamid, Yasuko Yanagida, and Takeshi Hatsuzawa. "Multipolar Electrical Forces for Microscale Particle Manipulation." Journal of Computational and Theoretical Nanoscience 6, no. 3 (2009): 505–13. http://dx.doi.org/10.1166/jctn.2009.1061.
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Arai, Fumihito, Toshiaki Endo, Ryuji Yamauchi, Toshio Fukuda, Toshimi Shimizu, and Shoko Kamiya. "3D Manipulation of Lipid Nanotubes with Functional Gel Microbeads." Journal of Robotics and Mechatronics 19, no. 2 (2007): 198–204. http://dx.doi.org/10.20965/jrm.2007.p0198.
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We developed a novel technique for manipulating lipid nanotubes in 3D space by using laser tweezers in water solutions. Laser tweezers are well known for their use in noncontact manipulation in a closed space. We reported on 3D 6DOF manipulation of microbeads using 3D synchronized laser micromanipulation (SLM), but blur is generated in the microscope image when multiple points at different heights are trapped by scanning the focal point of the laser. It is difficult to manipulate a nanoscale rod-like object stably in 3D space, since the optical trap force is weak. To manipulate a lipid nanotube, for example, we developed an observation system to less image blur by synchronizing the shutter timing of the CCD camera and laser scanning. We thus obtained a clear image of targets at different heights while manipulating them. We then developed functional gel microtools that adhere to lipid nanotubes and succeeded in controlling the position and orientation of lipid nanotubes by using 3D SLM with shutter timing control and novel functional gel microtools.