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This work was supported by the National Research Foundation of Korea (NRF) Grant funded by the Korea government (MSIT) (No. 2019R1A2C2011293) and the UK Engineering and Physical Sciences Research Council (Grant EP/P030017/1). ; We report a new method to optically manipulate a single dielectric particle along closed-loop polygonal trajectories by crossing a suite of all-fiber Bessel-like beams within a single water droplet. Exploiting optical radiation pressure, this method demonstrates the circulation of a single polystyrene bead in both a triangular and a rectangle geometry enabling the trapped particle to undergo multiple circulations successfully. The crossing of the Bessel-like beams creates polygonal corners where the trapped particles successfully make abrupt turns with acute angles, which is a novel capability in microfluidics. This offers an optofluidic paradigm for particle transport overcoming turbulences in conventional microfluidic chips. ; Publisher PDF ; Peer reviewed

"This is the peer reviewed version of the following article: Particle and Particle Systems Characterization 36.91 (2019): 1900233 which has been published in final form at https://doi.org/10.1002/ppsc.201900233. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley's version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited" ; Optical and optoelectronic techniques for micro- and nano-object manipulation are becoming essential tools in nano- and biotechnology. Among optoelectronic manipulation platforms, photovoltaic optoelectronic tweezers (PVOTs) are an emergent technique that are particularly successful at producing permanent nanoparticle microstructures. New strategies to enhance the capabilities of PVOT, based on real-time operation, are investigated. This optoelectronic platform uses z-cut LiNbO3:Fe substrates under excitation by a Gaussian light beam. Unexpected results show that during illumination, metallic particles previously deposited on the substrate are ejected from the light spot region. This behavior differs from the trapping phenomenon observed in previous work on PVOT operation, using a sequential method in which illumination is prior to particle manipulation. To discuss the results, a novel mechanism of charge exchange between particles and the ferroelectric substrate is proposed. Applications of this repulsion behavior are investigated. On the one hand, either particle repulsion or trapping in the illuminated region can be obtained by simply light switching on/off. On the other hand, by moving the light spot, different kinds of arbitrarily shaped tracks along the light path, either empty or filled with particles, are obtained. The results demonstrate new key capabilities of PVOT, such as pattern drawing, erasure, and reconfiguration ; Financial support from Ministerio de Ciencia, Innovación y Universidades of Spain (MAT2014-57704-C3, MAT2017-83951-R) is gratefully acknowledged

Intro -- MICROFLUIDICS -- MICROFLUIDICS -- CONTENTS -- PREFACE -- DIELECTROPHORESIS BASED DROPLET MICROFLUIDIC DEVICES FOR ON-CHIP BIOASSAYS -- ABSTRACT -- 1. INTRODUCTION -- 1.1. Close Channel Microfluidic Device or, Analog Microfluidic Device -- 1.2. Surface Microfluidic Device or, Digital Microfluidic Device -- 2. THEORY -- 2.1. Liquid Dielectrophoresis- The Phenomena and Its Characteristic Features -- L-DEP- Theoretical background -- Lumped capacitance model for homogenous L-DEP actuation -- Effective capacitance model for uniform, non-homogenous L-DEP actuation -- 2.2. L-DEP - Jet Actuation: Characteristic Features -- Threshold actuation voltage -- Threshold actuation frequency -- Droplet formation - key requirements/constraints -- Break-Up of Non-Uniform, Tapered Liquid Jets -- 2.3. Droplet-Dielectrophoresis (D-DEP): Underlying Concept and Actuation Methodology -- 2.4. Manipulating Micro-Particles Leveraging L-DEP -- 3. PRACTICAL L-DEP DEVICES- FABRICATION METHODS -- 3.1. Fundamentals of Device Fabrication -- 3.2. Approaches for Reliable and Repeatable Device Operation -- 3.3. Process for L-DEP and D-DEP - Multilayer and Device Integration -- 4. BIO-SAMPLE MANIPULATION AND SENSING APPLICATIONS -- Droplet based bio-assays -- Vesicular bio-applications -- Bead-based bio-assays -- CONCLUSION -- FUTURE WORK -- ACKNOWLEDGMENTS -- REFERENCES -- MICROFLUIDIC BIOSENSOR SYSTEMS FOR CELL BIOLOGY AND DRUG DISCOVERY -- ABSTRACT -- INTRODUCTION -- LABEL-FREE BIOSENSORS FOR CELL ANALYSIS -- MICROFLUIDIC BIOSENSOR SYSTEMS -- MICROFLUIDIC CELL CULTURE -- MICROFLUIDIC BIOSENSORS FOR ON-CHIP ELECTROPHYSIOLOGY ANALYSIS -- MICROFLUIDIC BIOSENSORS FOR SENSING CELL MECHANICS -- MICROFLUIDIC BIOSENSORS FOR PROBING CELLULAR RESPONSES AND DRUG ACTIONS UNDER CONTROLLED CHEMICAL ENVIRONMENTS -- MICROFLUIDIC BIOSENSORS FOR SINGLE CELL ANALYSIS -- CONCLUSION.

8 pages, 3 figures.-- Data are publicly available through the Gulf of Mexico Research Initiative Information & Data Cooperative (GRIIDC) at https://data.gulfresearchinitiative.org (doi:10.7266/N7H70CV7) ; Oil spills are one of the most dangerous sources of pollution in aquatic ecosystems. Owing to their pivotal position in the food web, pelagic copepods can provide crucial intermediary transferring oil between trophic levels. In this study we show that the calanoid Paracartia grani can actively modify the size-spectrum of oil droplets. Direct manipulation through the movement of the feeding appendages and egestion work in concert, splitting larger droplets (Ø = 16 µm) into smaller ones (Ø = 4-8 µm). The copepod-driven change in droplet size distribution can increase the availability of oil droplets to organisms feeding on smaller particles, sustaining the transfer of petrochemical compounds among different compartments. These results raise the curtain on complex small-scale interactions which can promote the understanding of oil spills fate in aquatic ecosystems ; This research was made possible by a grant from The Gulf of Mexico Research Initiative. [.] MU was sponsored by the MOKA project (Modelling and Observation of zooplanKtonic orgAnisms; ID: RBFR10VF6M) financed by the Italian Ministry of Education, University and Research, and by SZN internal grant. PH was supported by the Simons Foundation grant "Collaboration on Mathematical Biology" (278436). JM was the financed by the Support for Undergraduate Research Fellows (SURF) and the Center for International Education (CIE), University of Wisconsin-Milwaukee. HJ was supported by NSF grant no. OCE-1433979. MA was funded by the Spanish research project TOPCOP (CTM2011–23480, from the Spanish Ministry of Education and Science, and 2009SGR-1283 from the Catalan Government) ; Peer Reviewed

Optical forces allow manipulation of small particles and control of nanophotonic structures with light beams. While some techniques rely on structured light to move particles using field intensity gradients, acting locally, other optical forces can push particles on a wide area of illumination but only in the direction of light propagation. Here we show that spin orbit coupling, when the spin of the incident circularly polarized light is converted into lateral electromagnetic momentum, leads to a lateral optical force acting on particles placed above a substrate, associated with a recoil mechanical force. This counterintuitive force acts in a direction in which the illumination has neither a field gradient nor propagation. The force direction is switchable with the polarization of uniform, plane wave illumination, and its magnitude is comparable to other optical forces. ; This work has been supported, in part, by EPSRC (UK). A.V.Z. acknowledges support from the Royal Society and the Wolfson Foundation. N.E. acknowledges partial support from the US Office of Naval Research Multidisciplinary University Research Initiative Grant No. N00014-10-1-0942. A.M. acknowledges support from the Spanish Government (contract Nos TEC2011-28664-C02-02 and TEC2014-51902-C2-1-R). ; Rodríguez Fortuño, FJ.; Engheta, N.; Martínez Abietar, AJ.; Zayats, AV. (2015). Lateral forces on circularly polarizable particles near a surface. Nature Communications. 6(8799):1-7. https://doi.org/10.1038/ncomms9799 ; S ; 1 ; 7 ; 6 ; 8799 ; Novotny, L. & Hecht, B. Principles of Nano-Optics Cambridge University Press (2011). ; Jackson, J. D. Classical Electrodynamics Wiley (1998). ; Ashkin, A. & Dziedzic, J. M. Optical levitation by radiation pressure. Appl. Phys. Lett. 19, 283 (1971). ; Ashkin, A. Acceleration and trapping of particles by radiation pressure. Phys. Rev. Lett. 24, 156–159 (1970). ; Omori, R., Kobayashi, T. & Suzuki, A. Observation of a single-beam gradient-force optical trap for dielectric particles in air. Opt. Lett. 22, ...

It is thought that during immobilization enzymes, as dynamic biomolecules, may become distorted and this may alter their catalytic properties. However, the effects of different immobilization strategies on enzyme rigidity or flexibility and their consequences in specificity and stereochemistry at large scale has not been yet clearly evaluated and understood. This was here investigated by using as model an ester hydrolase, isolated from a bacterium inhabiting a karstic lake, with broad substrate spectrum (72 esters being converted; 61.5 U mg−1 for glyceryl tripropionate) but initially non-enantiospecific. We found that the enzyme (7 nm × 4.4 nm × 4.2 nm) could be efficiently ionic exchanged inside the pores (9.3 nm under dry conditions) of amino-functionalized ordered mesoporous material (NH2-SBA-15), achieving a protein load of 48 mg g−1, and a specific activity of 4.5 ± 0.1 U mg−1. When the enzyme was site-directed immobilized through His interaction with an immobilized cationon the surface of two types of magnetic micro-particles through hexahistidine-tags, protein loads up to 10.2 μg g−1 and specific activities of up to 29.9 ± 0.3 U mg−1, were obtained. We found that ionically exchanged enzyme inside pores of NH2-SBA-15 drastically narrowed the substrate range (17 esters), to an extent much higher than ionically exchanged enzyme on the surface of magnetic micro-particles (up to 61 esters). This is attributed to differences in surface chemistry, particle size, and substrate accessibility to the active site tunnel. Our results also suggested, for the first time, that immobilization of enzymes in pores of similar size may alter the enzyme structures and produce enzyme active centers with different configuration which promote stereochemical conversions in a manner different to those arising from surface immobilization, where the strength of the ionic exchange also has an influence. This was shown by demonstrating that when the enzyme was introduced inside pores with a diameter (under dry conditions) slightly higher than that of the enzyme crystal structure a biocatalyst enantiospecific for ethyl (R)-4-chloro-3-hydroxybutyrate was produced, a feature not found when using wider pores. By contrast, immobilization on the surface of ferromagnetic microparticles produced selective biocatalysts for methyl (S)-(+)-mandelate or methyl (S)-lactate depending on the functionalization. This study illustrates the benefits of extensive analysis of the substrate spectra to better understand the effects of different immobilization strategies on enzyme flexibility/rigidity, as well as substrate specificity and stereochemistry. Our results will help to design tunable materials and interfaces for a controlled manipulation of specificity and to transform non-enantiospecific enzymes into stereo-chemically substrate promiscuous biocatalysts capable of converting multiple chiral molecules. ; This project received funding from the European Union's Horizon 2020 research and innovation program Blue Growth: Unlockingthe potential of Seas and Oceans under grant agreement no. 634486 (project acronym INMARE). This research was also supported by the grants PCIN-2014-107 (within ERA NET IB2 grant nr. ERA-IB-14-030 - MetaCat), PCIN-2017-078 (within the ERA-MarineBiotech grant ProBone), BIO2014-54494-R, MAT2016-77496-R, BIO2017-85522-R, and CTQ2016-79138-R from the Spanish Ministry of Economy, Industry and Competitiveness. A.B. acknowledges the support from the Spanish Ministry of Economy, Industry and Competitiveness (MAT2017-88808-R grant), María de Maeztu Units of Excellence Programme (MDM-2016-0618), and the Diputación de Guipúzcoa for current funding in the frame of Gipuzkoa Fellows program. G.D. thanks the German Federal Ministry of Education and Research (BMBF, Grant No. 031A095C) for funding in the frame of the Molecular Interaction Engineering program (Biotechnologie 2020+). The authors gratefully acknowledge financial support provided by the European Regional Development Fund (ERDF). C.C. thanks the Spanish Ministry of Economy, Industry and Competitiveness for a PhD fellowship (Grant BES-2015-073829). ; Peer Reviewed ; Postprint (published version)

It is thought that during immobilization enzymes, as dynamic biomolecules, may become distorted and this may alter their catalytic properties. However, the effects of different immobilization strategies on enzyme rigidity or flexibility and their consequences in specificity and stereochemistry at large scale has not been yet clearly evaluated and understood. This was here investigated by using as model an ester hydrolase, isolated from a bacterium inhabiting a karstic lake, with broad substrate spectrum (72 esters being converted; 61.5 U mg−1 for glyceryl tripropionate) but initially non-enantiospecific. We found that the enzyme (7 nm × 4.4 nm × 4.2 nm) could be efficiently ionic exchanged inside the pores (9.3 nm under dry conditions) of amino-functionalized ordered mesoporous material (NH2-SBA-15), achieving a protein load of 48 mg g−1, and a specific activity of 4.5 ± 0.1 U mg−1. When the enzyme was site-directed immobilized through His interaction with an immobilized cationon the surface of two types of magnetic micro-particles through hexahistidine-tags, protein loads up to 10.2 μg g−1 and specific activities of up to 29.9 ± 0.3 U mg−1, were obtained. We found that ionically exchanged enzyme inside pores of NH2-SBA-15 drastically narrowed the substrate range (17 esters), to an extent much higher than ionically exchanged enzyme on the surface of magnetic micro-particles (up to 61 esters). This is attributed to differences in surface chemistry, particle size, and substrate accessibility to the active site tunnel. Our results also suggested, for the first time, that immobilization of enzymes in pores of similar size may alter the enzyme structures and produce enzyme active centers with different configuration which promote stereochemical conversions in a manner different to those arising from surface immobilization, where the strength of the ionic exchange also has an influence. This was shown by demonstrating that when the enzyme was introduced inside pores with a diameter (under dry conditions) slightly higher than that of the enzyme crystal structure a biocatalyst enantiospecific for ethyl (R)-4-chloro-3-hydroxybutyrate was produced, a feature not found when using wider pores. By contrast, immobilization on the surface of ferromagnetic microparticles produced selective biocatalysts for methyl (S)-(+)-mandelate or methyl (S)-lactate depending on the functionalization. This study illustrates the benefits of extensive analysis of the substrate spectra to better understand the effects of different immobilization strategies on enzyme flexibility/rigidity, as well as substrate specificity and stereochemistry. Our results will help to design tunable materials and interfaces for a controlled manipulation of specificity and to transform non-enantiospecific enzymes into stereo-chemically substrate promiscuous biocatalysts capable of converting multiple chiral molecules. ; This project received funding from the European Union's Horizon 2020 research and innovation program Blue Growth: Unlockingthe potential of Seas and Oceans under grant agreement no. 634486 (project acronym INMARE). This research was also supported by the grants PCIN-2014-107 (within ERA NET IB2 grant nr. ERA-IB-14-030 - MetaCat), PCIN-2017-078 (within the ERA-MarineBiotech grant ProBone), BIO2014-54494-R, MAT2016-77496-R, BIO2017-85522-R, and CTQ2016-79138-R from the Spanish Ministry of Economy, Industry and Competitiveness. A.B. acknowledges the support from the Spanish Ministry of Economy, Industry and Competitiveness (MAT2017-88808-R grant), María de Maeztu Units of Excellence Programme (MDM-2016-0618), and the Diputación de Guipúzcoa for current funding in the frame of Gipuzkoa Fellows program. G.D. thanks the German Federal Ministry of Education and Research (BMBF, Grant No. 031A095C) for funding in the frame of the Molecular Interaction Engineering program (Biotechnologie 2020+). The authors gratefully acknowledge financial support provided by the European Regional Development Fund (ERDF). C.C. thanks the Spanish Ministry of Economy, Industry and Competitiveness for a PhD fellowship (Grant BES-2015-073829). ; Peer Reviewed ; Postprint (published version)

Multi-body systems (MSs) are assemblies composed of multiple bodies (either rigid or structurally flexible) connected among each other by means of mechanical joints. In many engineering fields (such as aerospace, aeronautics, robotics, machinery, military weapons and bio-mechanics) a large number of systems (e.g. space robots, aircraft, terrestrial vehicles, industrial machinery, launching systems) can be included in this category. The dynamic characteristics and performance of such complex systems need to be accurately and rapidly analyzed and predicted. Taking this engineering background into consideration, a new branch of study, named as Multi-body Systems Dynamics (MSD), emerged in the 1960s and has become an important research and development area in modern mechanics; it mainly addresses the theoretical modeling, numerical analysis, design optimization and control for complex MSs. The research on dynamics modeling and numerical solving techniques for rigid multi-body systems has relatively matured and perfected through the developments over the past half century. However, for many engineering problems, the rigid multi-body system model cannot meet the requirements in terms of precision. It is then necessary to consider the coupling between the large rigid motions of the MS components and their elastic displacements; thus the study of the dynamics of flexible MSs has gained increasing relevance. The flexible MSD involves many theories and methods, such as continuum mechanics, computational mechanics and nonlinear dynamics, thus implying a higher requirement on the theoretical basis. Robotic on-orbit operations for servicing, repairing or de-orbiting existing satellites are among space mission concepts expected to have a relevant role in a close future. In particular, many studies have been focused on removing significant debris objects from their orbit. While mission designs involving tethers, nets, harpoons or glues are among options studied and analyzed by the scientific and industrial community, the debris removal by means of robotic manipulators seems to be the solution with the longest space experience. In fact, robotic manipulators are now a well-established technology in space applications as they are routinely used for handling and assembling large space modules and for reducing human extravehicular activities on the International Space Station. The operations are generally performed in a tele-operated approach, where the slow motion of the robotic manipulator is controlled by specialized operators on board of the space station or at the ground control center. Grasped objects are usually cooperative, meaning they are capable to re-orient themselves or have appropriate mechanisms for engagement with the end-effectors of the manipulator (i.e. its terminal parts). On the other hand, debris removal missions would target objects which are often non-controlled and lacking specific hooking points. Moreover, there would be a distinctive advantage in terms of cost and reliability to conduct this type of mission profile in a fully autonomous manner, as issues like obstacle avoidance could be more easily managed locally than from a far away control center. Space Manipulator Systems (SMSs) are satellites made of a base platform equipped with one or more robotic arms. A SMS is a floating system because its base is not fixed to the ground like in terrestrial manipulators; therefore, the motion of the robotic arms affects the attitude and position of the base platform and vice versa. This reciprocal influence is denoted as "dynamic coupling" and makes the dynamics modeling and motion planning of a space robot much more complicated than those of fixed-base manipulators. Indeed, SMSs are complex systems whose dynamics modeling requires appropriate theoretical and mathematical tools. The growing importance SMSs are acquiring is due to their operational ductility as they are able to perform complicated tasks such as repairing, refueling, re-orbiting spacecraft, assembling articulated space structures and cleaning up the increasing amount of space debris. SMSs have also been employed in several rendezvous and docking missions. They have also been the object of many studies which verified the possibility to extend the operational life of commercial and scientific satellites by using an automated servicing spacecraft dedicated to repair, refuel and/or manage their failures (e.g. DARPA's Orbital Express and JAXA's ETS VII). Furthermore, Active Debris Removal (ADR) via robotic systems is one of the main concerns governments and space agencies have been facing in the last years. As a result, the grasping and post-grasping operations on non-cooperative objects are still open research areas facing many technical challenges: the target object identification by means of passive or active optical techniques, the estimation of its kinematic state, the design of dexterous robotic manipulators and end-effectors, the multi-body dynamics analysis, the selection of approaching and grasping maneuvers and the post-grasping mission planning are the main open research challenges in this field. The missions involving the use of SMSs are usually characterized by the following typical phases: 1. Orbital approach; 2. Rendez-vous; 3. Robotic arm(s) deployment; 4. Pre-grasping; 5. Grasping and post-grasping operations. This thesis project will focus on the last three. The manuscript is structured as follows: Chapter 1 presents the derivation of a multi-body system dynamics equations further developing them to reach their Kane's formulation; Chapter 2 investigates two different approaches (Particle Swarm Optimization and Machine Learning) dealing with a space manipulator deployment maneuver; Chapter 3 addresses the design of a combined Impedance+PD controller capable of accomplishing the pre-grasping phase goals and Chapter 4 is dedicated to the dynamic modeling of the closed-loop kinematic chain formed by the manipulator and the grasped target object and to the synthesis of a Jacobian Transpose+PD controller for a post-grasping docking maneuver. Finally, the concluding remarks summarize the overall thesis contribution.

[EN] Acoustic vortex beams have great potential for contactless particle manipulation and torque-based biomedical applications. However, when focusing acoustic waves through aberration layers such as the human skull at ultrasonic frequencies results in strong phase aberrations which prevent the generation of sharp acoustic images. In the case of a wavefront containing phase dislocations, skull aberrations inhibit the focusing of acoustic vortex beams inside the cranial cavity. In this work, we demonstrate that phase-conjugated acoustic holograms can encode time-reversed fields simultaneously allowing the compensation of the aberrations of the skull and the generation of a focused vortex inside an ex-vivo human skull. The method is applied for single-element geometrically focused sources and results in a very simple and compact ultrasonic system. This work will pave the road to design low-cost particle trapping applications, clot manipulation, torque exertion in the brain and acoustic-radiation-force based biomedical applications. ; This research was supported by the Spanish Ministry of Science, Innovation, and Universities through "Juan de la Cierva-Incorporacion" Grants No. IJC2018-037897-I and No. PID2019-111436RB-C22, by the Agencia Valenciana de la Innovacio through Grants No. INNVAL10/19/016, No. INNVA1/2020/92, and No. INNCON/2020/009, and by the Generalitat Valenciana through Grant No. ACIF/2017/045. The action was cofinanced by the European Union through the Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of the Comunitat Valenciana, Grant No. IDIFEDER/2018/022. ; Jiménez-Gambín, S.; Jimenez, N.; Camarena Femenia, F. (2020). Transcranial focusing of ultrasonic vortices by acoustic holograms. Physical Review Applied. 14(5):1-10. https://doi.org/10.1103/PhysRevApplied.14.054070 ; S ; 1 ; 10 ; 14 ; 5 ; Elias, W. J., Huss, D., Voss, T., Loomba, J., Khaled, M., Zadicario, E., … Wintermark, M. (2013). A Pilot Study of Focused Ultrasound Thalamotomy for Essential Tremor. New England Journal ...

We employ conical refraction of light in a biaxial crystal to create an optical bottle for photophoretic trapping and manipulation of particles in gaseous media. We show that by only varying the polarization state of the input light beam the optical bottle can be opened and closed in order to load and unload particles in a highly controllable manner. ; This work was financially supported by the Australian Research Council, the National Health and Medical Research Council, the Spanish Ministry of Science and Innovation (MICINN grants FIS2011-23719 and AP2010-2310) and the Catalan Government (grant SGR2009- 00347).

We employ conical refraction of light in a biaxial crystal to create an optical bottle for photophoretic trapping and manipulation of particles in gaseous media. We show that by only varying the polarization state of the input light beam the optical bottle can be opened and closed in order to load and unload particles in a highly controllable manner. ; This work was financially supported by the Australian Research Council, the National Health and Medical Research Council, the Spanish Ministry of Science and Innovation (MICINN grants FIS2011-23719 and AP2010-2310) and the Catalan Government (grant SGR2009- 00347).

Retrocausation describes how an event that happens in the future may affect the present. For example, determining the state of an entangled particle in the future can determine the state of an entangled particle in the present. Recently, this phenomenon has been reported in the psychological literature, with several studies reporting that events which have yet to happen affect performance in various tasks. In this article, two classical manipulations of expectation from the psychological literature, endogenous and exogenous cueing, have been used to explore retrocausal effects on reaction speeds. The findings demonstrate no effect of retrocausation, supported by both frequentist and Bayesian statistical analysis. This is an important finding from two perspectives. First, it may indicate a limiting condition of retrocausal effects. Alternatively, it may contribute to research demonstrating a lack of retrocausation.