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Kuramitsu Yasuhiro, Sakai Kentaro, Moritaka Toseo. Electron scale magnetic reconnections in laser produced plasmas. Reviews of Modern Plasma Physics 7, 33–1 (2023); https://doi.org/10.1007/s41614-023-00125-4., Magnetic reconnection is a fundamental process in the universe, in which magnetic field energy is converted into plasma kinetic energy associated with a topological change in the magnetic field. Magnetic reconnections have been extensively investigated in space in the form of solar terrestrial plasmas, and also in laboratories in the form of magnetic confinement plasmas and laser-produced plasmas. Macroscopic features of magnetic reconnections can be well described in the context of magnetohydrodynamics (MHD) across a wide variety of research fields. However, how the kinetic regime of magnetic reconnection should be connected to the macroscopic MHD regime is still an open question. It is generally assumed that electron dynamics play an essential role in the triggering mechanism of magnetic reconnections. In this review, we discuss magnetic reconnections on the electron scale, focusing in particular on laboratory experiments using high-power lasers.

Laser filamentation is a fascinating phenomenon that occurs when an intense laser beam travels through transparent materials, in particular air. At sufficiently high power (TW in the near IR, GW in the UV), instead of spreading out like a regular laser beam, something remarkable happens: the laser beam becomes tightly focused, creating a thin and intense column of light called a laser filament. Laser filamentation is characterized by two main properties: (I) a high-intensity core that remains narrow over long distances beyond the Rayleigh range and (II) a low-density plasma channel within the core. In recent years, laser filamentation has gained significant attention due to its unique properties and wide range of applications. This dissertation will provide an introduction to laser filamentation and discuss beam profile measurements related to UV filaments. Additionally, the results of experiments involving the applications of laser filaments will be presented. It has been demonstrated that UV filaments can be utilized for laser breakdown spectroscopy, leading to higher resolution and accuracy. Furthermore, the phenomenon of air lasing induced by both UV and IR laser filaments was investigated. Finally, the potential application of UV filaments for guiding and triggering electrical discharges is studied.

Quanteninformationsexperimente mit gefangenen 40Ca+ Ionen benötigen einen schmalbandigen Laser bei einer Wellenlänge von 729 nm zum Anregen des Qubitübergangs zwischen 42S1/2 und 32D5/2. In dieser Arbeit wird ein Titan:Saphir-Laser beschrieben, welcher bei einer Wellenlänge von 729 nm mithilfe des Pound-Drever-Hall-Verfahrens auf einen externen Resonator frequenzstabilisiert wird. Die Laserlinienbreite wurde mittels Schwebungsmessungen mit anderen frequenzstabilisierten Lasern und Ramsey-Experimenten mit einem einzelnen gefangenen 40Ca+ gemessen. Die niedrigste gemessene Linienbreite (FWHM) wurde mittels einer Schwebungsmessung erhalten und beträgt 4.2(17) Hz bei einer Messzeit von 1 s, was eine obere Grenze für die Linienbreite des Titan:Saphir-Lasers darstellt. Diese niedrigste Linienbreite wurde erreicht, nachdem eine Vibrationsisolationsplatte unter dem Resonator installiert wurde. Eine Analyse der installierten Faserrauschunterdrückung und Laserintensitätsstabilisierung legt nahe, dass Faser- und Laserintensitätsrauschen die niedrigste gemessene Linienbreite nicht limitieren. Die Schwebungsmessungen mit anderen frequenzstabilisierten Lasern wurden zusätzlich verwendet, um einen Wert für die Drift der Laserfrequenz des stabilisierten Lasers zu erhalten, und die gemessene Drift ist -371(3) mHz/s., Quantum information science experiments with trapped 40Ca+ ions require a narrow-linewidth laser at a wavelength of 729 nm to drive the qubit transition between 42S1/2 and 32D5/2. In this thesis, a Titanium:Sapphire laser is presented that is frequency-stabilized to a reference cavity at a wavelength of 729 nm using the Pound-Drever-Hall technique. The laser linewidth was measured through beat measurements with other frequency-stabilized lasers and Ramsey experiments on a single trapped 40Ca+ ion. The narrowest measured linewidth (FWHM) was obtained via a beat measurement and is 4.2(17) Hz at a measurement time of 1 s, representing an upper limit for the Titanium:Sapphire laser linewidth. This narrowest linewidth was achieved after a vibration-isolation board was installed underneath the reference cavity. An analysis of the installed fiber noise cancellation and laser intensity stabilization suggests that fiber and laser intensity noise do not limit the narrowest measured linewidth. The beat measurements with other frequency-stabilized lasers were additionally used to obtain a value for the stabilized laser’s frequency drift, which is measured to be -371(3) mHz/s., presented by Armin Winkler, Zusammenfassung in deutscher Sprache, Masterarbeit University of Innsbruck 2023

presented by Alex Steiner, Zusammenfassung in deutscher Sprache, Kumulative Masterarbeit aus einem Artikel, Masterarbeit University of Innsbruck 2023

This work studies the combination of direct femtosecond laser structuring of metal surfaces and Spatial Atomic Layer Deposition (SALD) of metal oxides as a novel approach to generate colours on different types of day-to-day metallic objects. In particular, a stainless-steel knife and an outdated 25 ct Dutch florin coin have been selected for the study. Our results show that it is possible both, to preserve the iridescence properties produced by laser processing and to tune the final metal surface colour by controlling the thickness of the ZnO coating. At the same time, this oxide coating could act as a protecting layer for the original material. We thus explore two different strategies to generate colour, namely, iridescence and interference, which can be even developed selectively. This novel methodology to colour metallic surfaces is a promising route to achieve cheap, scalable, and high-throughput processing methods and opens up a new avenue of possibilities and applications related to colour.

Aim: The aim of this study is to evaluate the efficacy and safety of a YAG laser vitreolysis procedure used to remove bothersome vitreous opacities/floaters. Methods: The prospective clinical study included 42 eyes of 35 patients (age 32-81 years) with vitreous opacities generating visual disturbances. All patients were treated using the Ellex - Ultra Q Reflex YAG laser and underwent a complete eye examination before the laser vitreolysis and at 1, 3 and 6 months after the intervention. Changes in corrected distance visual acuity (CDVA), central retinal thickness (CRT), intraocular pressure (IOP) and patient’s subjective perception of disturbances were analysed. Results: The average number of laser shots was 118 (6 - 310 shots), with a total average energy of 3.8 mJ per laser shot (2.2 - 9 mJ). The laser intervention was performed only once in a total of 31 eyes (73.8%), whereas it was necessary to perform the intervention twice in 10 cases (23.8%). No significant differences in CDVA were detected during the whole follow-up (p>0.40). No significant changes were found either in CRT (p>0.32). Concerning IOP (p<0.001), it was reduced significantly immediately after the intervention, returning to the pre-intervention level afterwards. The analysis of the responses to the questionnaire revealed that there was a mean improvement in subjective visual symptoms according to patients of 71%. No complications were detected in the sample during the follow-up. Conclusion: Laser vitreolysis is a minimally invasive treatment, allowing a complete or partial elimination of vitreous opacities and leading to alleviation of patient’s disturbances.

Motivated by recent experimental initiatives, such as at the Helmholtz International Beamline for Extreme Fields (HIBEF) at the European X-ray Free Electron Laser (XFEL), we calculate the birefringent scattering of x-rays at the combined field of two optical (or near-optical) lasers and compare various scenarios. % In order to facilitate an experimental detection of quantum vacuum diffraction and birefringence, special emphasis is placed on scenarios where the initial and final x-ray photons differ not just in polarization, but also in propagation direction (corresponding to scattering angles in the mrad regime) and possibly energy.

[Resumen] Introducción: El dolor plantar es un problema con el que convive un gran porcentaje de la población. Existen múltiples terapias que tratan de resolver este hecho, pero que en muchas ocasiones se consideran ineficaces o demasiado prolongadas en el tiempo. Por ello, se considera importante conocer la efectividad del tratamiento con láser de diodo para solventar la fascitis plantar y así, valorar si sería interesante contar con este tipo de terapia en consulta, o de lo contrario, no sería más efectiva que otras terapias que se venían utilizando previamente para la resolución de esta patología. Objetivo principal: determinar la efectividad de la laserterapia para la resolución de la fascitis plantar en clínica. Objetivos secundarios: Analizar las características clínico-antropométricas, y variables asociadas de los pacientes diagnosticados de fascitis plantar, comprobar que el láser reduce el engrosamiento de la fascia mediante las mediciones ecográficas además de determinar si existen cambios degenerativos previos en el patrón fibrilar de la fascia antes de ser sometida a laserterapia. Metodología: Se llevará a cabo un estudio cuasiexperimental, longitudinal de metodología cuantitativa en el que se contará con una muestra de 23 sujetos que presenten fascitis plantar en la Clínica Podológica Universitaria de Ferrol, provincia de A Coruña. Después de haber firmado el consentimiento informado y haber respondido a los distintos cuestionarios validados relacionados con el dolor y la actividad física (IPAQ 7, FFI, EVA), los pacientes previamente diagnosticados de fascitis plantar, acudirán a consulta para realizar pruebas de acortamiento de la cadena posterior mediante el test de Silverskiold, mediciones ecográficas y a mayores, recibirán la primera de las 10 sesiones del tratamiento de láser que abarcará un periodo de tiempo de 2 meses. Se finalizará la recogida de datos volviendo a realizar las mismas mediciones y test que en la primera visita del paciente. Tras, [Resumo] Introdución: A dor plantar é un problema co que vive unha gran porcentaxe da poboación. Son múltiples as terapias que tratan de resolver este feito, pero en moitas ocasións considéranse ineficaces ou demasiado longas no tempo. Por este motivo, considérase importante coñecer a efectividade do tratamento con láser de diodo para resolver a fascitis plantar e así valorar se sería interesante contar con este tipo de terapia no consultorio, ou se non, non sería máis efectiva que outras terapias que se viñan utilizando previamente para a resolución desta patoloxía. Obxectivo principal: determinar a eficacia da terapia con láser para a resolución da fascitis plantar clínica. Obxectivos secundarios: Analizar as características clínico-antropométricas e as variables asociadas dos pacientes diagnosticados de fascitis plantar, comprobar que o láser reduce o engrosamento da fascia mediante medicións ecográficas, ademais de determinar se existen cambios dexenerativos previos no patrón fibrilar de a fascia, antes de someterse a terapia con láser. Metodoloxía: Realizarase un estudo cuasi-experimental, lonxitudinal, de metodoloxía cuantitativa no que haberá unha mostra de 23 suxeitos que presenten fascitis plantar na Clínica Podolóxica Universitaria de Ferrol, provincia da Coruña. Tras asinar o consentimento informado e ter respondido os diferentes cuestionarios validados, relacionados coa dor e a actividade física (IPAQ 7, FFI, EVA), os pacientes previamente diagnosticados de fascitis plantar, acudirán á consulta para realizar probas de acurtamento da cadea posterior mediante o a proba de Silverskiold, as medicións ecográficas e en adición, recibirán a primeira das 10 sesións de tratamento con láser que abarcará un período de 2 meses. A recollida de datos completarase repetindo as mesmas medicións e probas que na primeira visita do paciente. Despois de rexistrar as variables a estudar, finalizarase o tratamento e realizarase a análise de datos para verificar a diferenza en, [Abstract] Introduction: Plantar pain is a problem with which a large percentage of the population lives. There are multiple therapies that try to resolve this fact, but on many occasions they are considered ineffective or too long in time. For this reason, it is considered important to know the effectiveness of diode laser treatment to solve plantar fasciitis and thus assess whether it would be interesting to have this type of therapy in the office, or otherwise, it would not be more effective than other therapies that are had previously been using for the resolution of this pathology. Main objective: to determine the effectiveness of laser therapy for the resolution of clinical plantar fasciitis. Secondary objectives: To analyze the clinical-anthropometric characteristics and associated variables of patients diagnosed with plantar fasciitis, to verify that the laser reduces the thickening of the fascia through ultrasound measurements, in addition to determining if there are previous degenerative changes in the fibrillar pattern of the fascia. before undergoing laser therapy. Methodology: A quasi-experimental, longitudinal study of quantitative methodology will be carried out in which there will be a sample of 23 subjects who present plantar fasciitis at the Clínica Podológica Universitaria de Ferrol, province of A Coruña. After having signed the informed consent and having responded to the different validated questionnaires related to pain and physical activity (IPAQ 7, FFI, EVA), patients previously diagnosed with plantar fasciitis will come to the consultation to perform shortening tests of the posterior chain using the Silverskiold test, ultrasound measurements and the elderly will receive the first of 10 laser treatment sessions that will cover a period of 2 months. The data collection will be completed by repeating the same measurements and tests as in the patient's first visit. After registering the variables to be studied, the treatment will be concluded an

Aromatic plants and laser beam wavelength in the red range of visible spectra (623.8 nm), most commonly used for treating plant species, were selected. As there is not much information in the references, it is necessary to set a scale with qualitative and partially quantitative evaluations of the results. Specimens of thyme seed (Thymus vulgaris) were selected as aromatic plants for studying the effect of low-power lasers on plant development, and continuous He-Ne laser, with irradiation times in the range of minutes.

© 2011 American Institute of Physics. Authors would like to acknowledge the Nanotechnology and Surface Analysis Services of the Universidad de Vigo C.A.C.T.I. for ToF-SIMS measurements, C.A.I. de Microscopía of the Universidad Complutense de Madrid for TEM measurements and C.A.I. de Técnicas Físicas of the Universidad Complutense de Madrid for ion implantation experiments. This work was partially supported by the projects NUMANCIA-II (Grant No. S2009/ENE/1477) funded by the Comunidad de Madrid and GENESIS-FV (Grant No. CSD2006-00004) funded by the Spanish Consolider National Program., A detailed study on the resulting impurity profile in Si samples implanted with high doses of Ti and subsequently annealed by pulsed-laser melting (PLM) is reported. Two different effects are shown to rule the impurity profile redistribution during the annealing. During the melting stage, the thickness of the implanted layer increases while the maximum peak concentration decreases (box-shaped effect). On the contrary, during the solidifying stage, the thickness of the layer decreases and the maximum peak concentration increases (snow-plow effect). Both effects are more pronounced as the energy density of the annealing increases. Moreover, as a direct consequence of the snow-plow effect, part of the impurities is expelled from the sample through the surface., Comunidad de Madrid, Ministerio de Ciencia e Innovación (MICINN), Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2000 Kluwer Academic Publishers. The research work leading to this paper was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain, Project PB97-295. The stay of J.M. Movilla at the Technische Universität in Berlin was supported by a grant of the Universidad Complutense of Madrid. We would also like to thank Prof. H. Weber, Mr. A. Vázquez and Mr. G. Mann from the Optisches Institut at the Technische Universität in Berlin for helpful discussions as well as continuous interest and support all along the experimental work described in Section 4., On the basis of well-known methods to obtain the standard Stokes parameters, two simple experimental procedures are analysed to measure the so-called generalized degree of polarization, P, defined elsewhere [Opt. Commun., 149 (1998) 230]. After discussing the accuracy of the methods, the generalized degree of polarization of a non-uniformly polarized beam emerging from an optically pumped birefringent Nd:YAG rod optically pumped is experimentally investigated in terms of the pumped power., Comisión Interministerial de Ciencia y Tecnología of Spain, Universidad Complutense of Madrid, Depto. de Óptica, Fac. de Ciencias Físicas, TRUE, pub

© 2015 American Physical Society, Broadband ultrashort terahertz (THz) pulses can be produced using plasma generation in a noble gas ionized by femtosecond two-color pulses. Here we demonstrate that, by using multiple-frequency laser pulses, one can obtain a waveform which optimizes the free electron trajectories in such a way that they acquire the largest drift velocity. This allows us to increase the THz conversion efficiency to 2%, an unprecedented performance for THz generation in gases. In addition to the analytical study of THz generation using a local current model, we perform comprehensive 3D simulations accounting for propagation effects which confirm this prediction. Our results show that THz conversion via tunnel ionization can be greatly improved with well-designed multicolor pulses., DFG, Sección Deptal. de Óptica (Óptica), Fac. de Óptica y Optometría, TRUE, pub

© 2013 AIP Publishing LLC. he authors would like to acknowledge the C.A.I. de Técnicas Físicas for ion implantation experiments and e-beam evaporations, the Nanotechnology and Surface Analysis Services of the Universidad de Vigo C.A.C.T.I. for ToF-SIMS measurements, Dr. J. Herrero (CIEMAT) for UVVIS-IR measurements facilities, and the Instituto de Nanociencia de Aragón for the TEM images. J. Olea and D. Pastor thanks Professor A. Martí and Professor A. Luque for useful discussions and guidance and acknowledge financial support from the MICINN within the program Juan de la Cierva (JCI-2011-10402 and JCI-2011-11471), under which this research was undertaken. Research by E. Garcìa-Hemme has been partly supported by a PICATA predoctoral fellowship of the Moncloa Campus of International Excellence (UCM-UPM). This work was partially supported by the projects NUMANCIA II (S-2009/ENE-1477) founded by the Regional Government of Comunidad de Madrid and grant GR35/10-A founded by the Universidad Complutense de Madrid., In this study, we present a structural and optoelectronic characterization of high dose Ti implanted Si subsequently pulsed-laser melted (Ti supersaturated Si). Time-of-flight secondary ion mass spectrometry analysis reveals that the theoretical Mott limit has been surpassed after the laser process and transmission electron microscopy images show a good lattice reconstruction. Optical characterization shows strong sub-band gap absorption related to the high Ti concentration. Photoconductivity measurements show that Ti supersaturated Si presents spectral response orders of magnitude higher than unimplanted Si at energies below the band gap. We conclude that the observed below band gap photoconductivity cannot be attributed to structural defects produced by the fabrication processes and suggest that both absorption coefficient of the new material and lifetime of photoexcited carriers have been enhanced due to the presence of a high Ti concentration. This remarkable result proves that Ti supersaturated Si is a promising material for both infrared detectors and high efficiency photovoltaic devices., Comunidad de Madrid, MICINN, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2001 Optical Society of America. We thank Franco Gori for many helpful discussions during the preparation of this work. We acknowledge the project Azioni Integrate HI-1998-077 for support. One of the authors (G. Piquero) is grateful for support from the project PB97-295 and the program Becas Internacionales U.C.M/Flores Valles., The effects of polarization gratings on partially coherent beams are investigated by studying a Gaussian Schell-model beam impinging on a linear polarizer whose transmission axis varies periodically along one transverse direction. Analytical expressions for the beam polarization-coherence matrix after the grating are obtained. In particular, the evolution of the degree of polarization upon propagation is analyzed. Different behaviors of the output beam, depending on the beam parameters and on the period of the grating, are exhibited. In particular, it is shown that, by suitably choosing the latter quantities, it is possible to obtain not only any desirable value of the degree of polarization of the output beam but also particular distributions of such. parameters across the transverse sections of the beam., Azioni Integrate (Acción Integrada Hispano-Italiana), Becas Internacionales UCM/Flores Valles, Depto. de Óptica, Fac. de Ciencias Físicas, TRUE, pub

© 2005 The American Physical Society. We are gratefully to Tomás Lorca L. Aranguren for a careful reading of the manuscript. This work was supported by the Projects No. PR3/04-12458 (UCM, Spain) and No. FIS2004-03267 (MEC, Spain)., The squeezing spectrum of the fluorescent light is investigated for a laser-driven three-level atom of the Lambda configuration when quantum interference of the decay channels is accounted for. We show that when the two atomic transitions contribute to the detected fluorescence field, squeezing at certain frequency intervals is obtained in both the weak- and the high-Rabi-frequency regimes even for equally decay rates of the transitions. Unlike in two-level atoms in free space, squeezing can be obtained in both the in-phase and out-of-phase quadrature spectra although in different spectral regions. We also show that the squeezing spectrum can be controlled by an adequate selection of the Rabi frequencies and atomic detunings. Another remarkable effect is that squeezing can be achieved with proper relative phases of the driving fields. We provide an analytical description in the dressed basis which accounts for the main features of the squeezing spectra obtained from the numerical work., Universidad Complutense de Madrid (UCM), Ministerio de Educación y Ciencia (MEC), España, Depto. de Óptica, Fac. de Ciencias Físicas, TRUE, pub

©2001 Elsevier Science B. V. We wish to thank Franco Gori for the helpful discussions and his valuable suggestions. We also acknowledge the project Acción Integrada Hispano-Italiana HI-1998-077. One of the authors (G.P.) thanks the support from a grant “Ayudas Complutense postdoctorales en el extranjero” and the project PB97-295., We analyze the polarization features of the beam, generated by a class of partially polarized quasi-homogeneous sources, which propagates through a polarization grating. Analytical expressions in the far zone for the beam coherence polarization matrix, the degree of polarization and the Stokes parameters are given. In particular, it is shown that, under some hypotheses, it is possible to completely and uniformly depolarize the beam in the far field. The influence of source parameters, such as the state of polarization, intensity and degree of coherence, on the degree of polarization and the Stokes parameters is also investigated., Acción Integrada Hispano-Italiana, Universidad Complutense de Madrid, Depto. de Óptica, Fac. de Ciencias Físicas, TRUE, pub

© 2004 Elsevier Ltd., We have studied the influence of the electron-lattice coupling on the luminescence quantum yield for Cr^3^+ ions in a Cs_2NaAlF_6 crystal. For this purpose, we analyze the absorption and emission spectra of Cr^3^+ ions by means of the configurational coordinate model in the harmonic approximation. We have found the energy of the breathing phonon associated to Cr^3^+ ions in this host. In our findings we explain the high value of luminescence quantum yield reported previously (near to 70%), if we take into account the uncoupling between the breathing phonon and the normal modes associated to the bulk vibration. The Cr^3^+:Cs_2NaAlF_6 crystals promise to be a potential efficiency tunable laser device in the near infrared (700–900 nm) spectral range., Depto. de Óptica, Fac. de Ciencias Físicas, TRUE, pub

© 1999 Kluwer Academic Publishers. This work was supported by the Comisión Interministerial de Ciencia y Tecnología of Spain under project PB97-0295, within the framework of EU-1269 project., Two overall parameters are proposed to characterize the degree of polarization and its uniformity across the transversal section of non-uniformly partially polarized beams. Such parameters can be measured according to the well-known standard methods used to obtain the Stokes parameters, with the addition of a CCD camera to determine the beam intensity at each point of the observation plane., Comisión Interministerial de Ciencia y Tecnología of Spain, Comunidad Europea, Depto. de Óptica, Fac. de Ciencias Físicas, TRUE, pub

The Department of Defense relies on many platforms that require inertial sensors to operate in Global Positioning System (GPS)–compromised environments to provide or verify navigational data. The current generation of sensors in use are subject to sensitivity limitations and drift errors that can compound significantly over time in GPS-contested areas. Inertial sensors based on atom interferometers could provide navigational data that is significantly more accurate and less prone to drift (and therefore navigational errors). This research builds upon previous work (Manicchia in 2020, Gervis in 2021) in which an atomic interferometer was constructed and studied. In this thesis, I demonstrate a path toward making inertially sensitive measurements with this apparatus. In contrast to the previous work, I use counter-propagating Raman fields that can achieve inertial sensitivity. However, these Raman fields are sensitive to non-trivial transverse velocities of our atom beam. I demonstrate a method to reduce these transverse velocities using an optical molasses, but do not pursue this in the apparatus due to spatial considerations. I explore the difference between Ramsey and spin echo spectroscopies, forms of atomic interference, in co- and counter-propagating configurations, the second of which is inertially sensitive. I also demonstrate that interference is still visible in the counter-propagating geometry, laying the foundation for a fully inertially sensitive interferometer., Captain, United States Marine Corps, Approved for public release. Distribution is unlimited.

Generation of human neuronal networks by three-dimensional (3D) bioprinting is promising for drug testing and hopefully will allow for the understanding of cellular mechanisms in brain tissue. The application of neural cells derived from human induced-pluripotent stem cells (hiPSCs) is an obvious choice, since hiPSCs provide access to cells unlimited in number and cell types that could be generated by differentiation. The questions in this regard include which neuronal differentiation stage is optimal for printing of such networks, and to what extent the addition of other cell types, especially astrocytes, supports network formation. These aspects are the focus of the present study, in which we applied a laser-based bioprinting technique and compared hiPSC-derived neural stem cells (NSCs) with neuronal differentiated NSCs, with and without the inclusion of co-printed astrocytes. In this study, we investigated in detail the effects of cell types, printed droplet size, and duration of differentiation before and after printing on viability, as well as proliferation, stemness, differentiation potential, formation of dendritic extensions and synapses, and functionality of the generated neuronal networks. We found a significant dependence of cell viability after dissociation on differentiation stage, but no impact of the printing process. Moreover, we observed a dependence of the abundance of neuronal dendrites on droplet size, a marked difference between printed cells and normal cell culture in terms of further differentiation of the cells, especially differentiation into astrocytes, as well as neuronal network formation and activity. Notably, there was a clear effect of admixed astrocytes on NSCs but not on neurons.

Hörgeräte ermöglichen es Menschen mit Schwerhörigkeit, weiterhin am Alltag und am sozialen Leben teilzunehmen. Am häufigsten tritt Altersschwerhörigkeit besonders im Bereich hoher Frequenzen auf. Je nach Art des Hörverlusts eignen sich z. B. akustische Hörgeräte oder, wenn diese nicht ausreichen, Mittelohr- oder Cochlea-Implantate. Mit einem Mittelohr-Implantat werden je nach Typus mechanische Schwingungen im Mittelohr aktiv erzeugt oder passiv über-tragen. Dabei erreichen die Implantate bei tiefen Töne häufig geringere Lautstärken als für hö-here Frequenzen. Wenn diese Lautstärken aufgrund stärkeren Hörverlusts nicht ausreichen, wird ein Cochlea-Implantat eingesetzt, wobei jedoch etwaige noch intakte Haarzellen im Innenohr zerstört werden. Zudem ist das dadurch erreichbare Hörvermögen insbesondere hinsichtlich der Anzahl und Auflösung der Frequenzen limitiert. Als Alternative zur Stimulation bei noch intak-ten Haarzellen mit einer höheren Lautstärke insbesondere bei tiefen Frequenzen wird in dieser Arbeit eine Stimulationsmethode entwickelt, die mittels Laserpulsen Töne erzeugt und im Mit-tel- oder Innenohr als Grundprinzip für ein Hörimplantat anwendbar ist. Ein gepulster Nahinfrarot-Laser mit einer Pulsdauer von 0,7 ns wurde in Wasser sowie in ein viskoses Gel fokussiert. Dadurch wurden Töne über den optoakustischen Effekt erzeugt. Dazu wurden ein Freistrahl-Aufbau mit einem Mikroskop-Objektiv sowie ein faserbasierter Aufbau konstruiert. Die erzeugten Drucktransienten wurden im Modellaufbau mittels eines Hydrofons zur Untersuchung der akustischen Frequenzanteile sowie mit einem Nadelhydrofon für eine detaillierte Zeitauflösung der Kavitationsdynamik gemessen. Die Effekte der Viskosität und der Geometrie auf den Druckverlauf und die zugrundeliegende Kavitationsdynamik wurden sowohl experimentell als auch mittels einer Simulation basierend auf der Toolbox OpenFOAM mit der Finite-Volumen-Methode untersucht. Zudem wurden Validierungsexperimente der Tonerzeugungsmetho

Bi2Se3 is an ideal three-dimensional topological insulator in which chemical modifications such as doping and intercalation can be used to engineer surface properties or to further functionalize the topological surface state. In this work, we study the Bi2Se3 system of materials with three experimental techniques: 1) ultrafast optical pump-probe spectroscopy (OPP), 2) angle-resolved photoemission spectroscopy (ARPES), and 3) X-ray photoelectron spectroscopy (XPS). These spectroscopic techniques are utilized to study the out-of- equilibrium carrier properties, surface chemistry, and band structure of Bi2Se3, Bi2–xSbxSe3, and CuxBi2Se3.The photoexcited carrier decay in Bi2–xSbxSe3 nanoplatelets was studied with ultrafast optical pump-probe spectroscopy, demonstrating a substantial slowing of the bulk carrier relaxation time in bulk-insulating Bi2–xSbxSe3 as compared to n-type bulk-metallic Bi2Se3 at low temperatures, which approaches 3.3 ns in the zero pump fluence limit. This long-lived decay is correlated across different fluences and antimony concentrations, revealing unique decay dynamics not present in n-type Bi2Se3, namely the slow bimolecular recombination of bulk carriers.Using ambient pressure X-ray photoelectron spectroscopy, copper migration in interca- lated CuxBi2Se3 is demonstrated, occurring on a timescale of hours to days after initial surface cleaving. The increase in near-surface copper proceeds along with the oxidation of the sample surface and large changes in the selenium content, with the development of copper and selenium gradients. These complex changes are further modelled with core level spectroscopy simulations (SESSA), which suggest a composition gradient near the surface which develops with oxygen exposure. These results shed light on a phenomenon that must be considered in intercalated topological insulators and intercalated materials in general.

ObjectivesDuring holmium:yttrium-aluminum-garnet (holmium:YAG) laser lithotripsy to break urinary stones, urologists frequently see flashes of light. As infrared laser pulses are invisible, what is the source of light? Here we studied the origin, characteristics, and some effects of flashes of light in laser lithotripsy.MethodsUltrahigh-speed video-microscopy was used to record single laser pulses at 0.2-1.0 J energy lasered with 242 µm glass-core-diameter fibers in contact with whole surgically retrieved urinary stones and hydroxyapatite (HA)-coated glass slides in air and water. Acoustic transients were measured with a hydrophone. Visible-light and infrared photodetectors resolved temporal profiles of visible-light emission and infrared-laser pulses.ResultsTemporal profiles of laser pulses showed intensity spikes of various duration and amplitude. The pulses were seen to produce dim light and bright sparks with submicrosecond risetime. The spark produced by the intensity spike at the beginning of laser pulse generated a shock wave in the surrounding liquid. The subsequent sparks were in a vapor bubble and generated no shock waves. Sparks enhanced absorption of laser radiation, indicative of plasma formation and optical breakdown. The occurrence and number of sparks varied even with the same urinary stone. Sparks were consistently observed at laser energy >0.5 J with HA-coated glass slides. The slides broke or cracked by cavitation with sparks in 63 ± 15% of pulses (1.0 J, N = 60). No glass-slide breakage occurred without sparks (1.0 J, N = 500).ConclusionUnappreciated in previous studies, plasma formation with free-running long-pulse holmium:YAG lasers can be an additional physical mechanism of action in laser procedures.

In 2018, the Endourology Disease Group for Excellence (EDGE) published a prospective trial comparing dusting versus basketing during ureteroscopy. One hundred fifty-nine patients were included in the original analysis, which found no difference in stone-free rate at 3 months. We report the intermediate and long-term outcomes of patients included in the original trial. Two analyses were performed. At 1-year, a retrospective chart review was performed, and data collected on stone episodes, Emergency Department (ED) visits, hospital admissions and surgical interventions. To obtain long-term outcomes, the four sites with the largest initial accrual were included in a second phase of data collection with updated analyses. The patients from those sites were contacted, re-consented, and data were collected on stone surgical interventions, stone episodes, stone recurrences on imaging, emergency department (ED) visits, and hospital admissions for stone-related care since their original procedure. One-year follow-up data were collected in 111 of the original 159 (69.8%) patients from the nine sites. There were no statistically significant differences in the number of painful episodes, ED visits, hospital admissions, or surgical interventions. 94 patients from four sites were included in the long-term analysis. There were no statistically significant differences in surgical interventions, painful stone episodes, stone recurrence on imaging, ED visits or hospitalizations for stone-related events between the two groups. Long-term outcomes of dusting versus basketing during ureteroscopy indicate that there are no significant differences in clinical outcomes between the two surgical modalities.

The project presented in this document is included within a line of work previously in progress for the complete design of a laser welding system. Thus, one of the parts (subprojects) in which the line of work was divided is presented: Design a board to control the required peripherals and add security to the system. Peripherals such as solenoid valves, buttons, lighting or cameras; and security such that the laser power is disconnected when certain situations occur. In addition, the board must be able to communicate with the computer incorporated in the welding system, to receive orders from the user as well as to provide information. The process of elaboration of said board implies the design of the electronics (Hardware) as well as the code (Firmware). It also requires carrying out a test plan that verifies the correct functioning of both parts separately and together., El proyecto expuesto en el presente documento se engloba dentro de una línea de trabajo previamente en curso para el diseño completo de un sistema de soldadura por láser. Así, se presenta una de las partes (subproyectos) en la que se dividió la línea de trabajo: Diseñar una placa para el control de los periféricos requeridos y añadir seguridad al sistema. Periféricos tales como electroválvulas, botones, iluminación o cámaras; y seguridad tal que la alimentación del láser se desconecte cuando se den determinadas situaciones. Además la placa ha de ser capaz de comunicarse con el ordenador incorporado en el sistema de soldadura, para recibir órdenes del usuario así como para darle información. El proceso de elaboración de mencionada placa implica el diseño de la electrónica (Hardware) así como del código (Firmware). Además requiere la realización de un plan de test que verifique el correcto funcionamiento de ambas partes por separado y en conjunto., El projecte exposat al present document s'engloba dins una línia de treball prèviament en curs per al disseny complet d'un sistema de soldadura per làser. Així, es presenta una de les parts (subprojectes) en què es va dividir la línia de treball: Dissenyar una placa pel control dels perifèrics requerits i afegir seguretat al sistema. Perifèrics com ara electrovàlvules, botons, il·luminació o càmeres; i seguretat per tal que l'alimentació del làser es desconnecti quan es donin determinades situacions. A més, la placa ha de ser capaç de comunicar-se amb l'ordinador incorporat al sistema de soldadura, per rebre ordres de l'usuari així com per donar-li informació. El procés d'elaboració de la placa esmentada implica el disseny de l'electrònica (Hardware) així com del codi (Firmware). A més, requereix la realització d'un pla de test que verifiqui el funcionament correcte d'ambdues parts per separat i en conjunt.

Semiconductor saturable absorber mirrors (SESAMs) are passive elements that have beenused in tandem with lasers in the visible and infrared wavelengths to generate mode-locked pulses for applications in communication and spectroscopy. In this thesis, the simulation and characterization of terahertz saturable absorber metasurfaces and mid-IR samples embedded with quantum-cascade (QC) absorbing material are discussed. The reflectance of each design is simulated to determine expected saturation parameters and compared with analytic estimates. The characterization of the saturable absorber involves focusing a QC-vertical external cavity surface emitting laser (VECSEL) onto a saturable absorber in a reflectionmode spectroscopy configuration to measure the reflected power. Using a gold mirror as a reference, the reflectance is measured for frequencies near 3.4 THz at room temperature. Improvements to this experiment and a preliminary design for an external cavity incorporating a saturable absorber metasurface are proposed.

In the entertainment industry, where temporary structures are erected in a new venue every day, floor markings play an important role during the set up. Today, mark out is commonly done using tape measures - a very tedious and time consuming process. This thesis explores the possibility to create a tool to assist in the mark out process, a mark out station. Two stations working in tandem would both compute their respective positions in the venue and accurately and precisely show the location of any wanted point, based on their coordinate locations. The mark out stations were built using consumer grade line lasers, stepper motors, common micro controllers and fused filament fabrication (FFF)-manufactured plastic components, as well as various other common hardware components. The software utilized already established triangulation algorithms and a custom control protocol to manage the mark out stations. A short range test on a test surface was performed with three different station placements. Placing the mark out stations in between three calibration points yielded better precision and accuracy in contrast to placing them on the edge of the surface. When placed on the edge, the calibration accuracy benefited from more calibration points, in contrast to placement in between calibration points. Next phase after successful short range testing is testing in a larger setting to conclude if this is a viable tool to assist in the mark out process. Further improvements in the calibration process and the mark out process can be made in future iterations to achieve better performance., Inom eventbranchen, där tillfälliga strukturer reses på nya platser varje dag, spelar markeringar på golvet en viktig roll. Idag sker utmärkningen med hjälp av måttband - en väldig tidskrävande process. Detta examnesarbete undersöker huruvida det går att utveckla ett verktyg som assisterar i denna utmärkningsprocess, en utmärkningsstation. De två stationerna som arbetar tillsammans skulle både beräkna deras respektive positioner på spelplatsen samt noggrant och precist visa placeringen av en önskad punkt, baserad på dess koordinater. Utmärkningsstationerna byggdes av konsumentlinjelasrar, stegmotorer, vanliga mikrokontrollers och FFF-tillverkade komponenter. Mjukvaran inkorporerar redan etablerade trianguleringsalgoritmer och ett egenskrivet kontrollprotokoll för att styra utmärkningsstationerna. Ett test på mindre avstånd gjordes på en testyta med tre olika stationsplaceringar. Att placera stationerna mellan tre kalibreringspunkter gav bättre noggranhet och precision än när stationerna placerades på utkanten av ytan. När stationerna placerades på utkanten av ytan, ökade noggrannheten och precisionen av att lägga till ytterligare kalibreringspunkter, till skillnad från placeringen mellan kalibreringspunkterna. Nästa fas, efter ett lyckat test på kort avstånd, är att testa på större avstånd för att undersöka om detta kan vara ett användbart vektyg inom utsättning. Ytterliggare förbättringar i kalibrerings- och utmärkningsprocessen kan göras i framtida iterationer för att uppnå en bättre prestanda.

presented by Alex Steiner, Zusammenfassung in deutscher Sprache, Kumulative Masterarbeit aus einem Artikel, Masterarbeit University of Innsbruck 2023

[EN] This project outlines the process of designing and customizing a mobile robot based on the RB-Vogui model from Robotnik Automation S.L., a leading global manufacturer of mobile robots and manipulators. The primary aim of this project is to meet specific customer requirements by integrating a novel safety system dependent on an external PLC connected to the customer’s LIDAR scanners. In addition to the new safety system, the project encompasses the upgrade of the robot’s software to support ROS2 middleware, reflecting an important transition for Robotnik’s software systems. This upgrade involves not only the integration of the standard robot software based on ROS1 but also a comprehensive research and development phase to enable the simultaneous operation of ROS1 and ROS2 within the same system. The project further involves a complete 3D design of the robot, assembling and testing individual components, and integrating additional software to accommodate the new safety system and the customer’s sensors. Systematic tests in both simulated and real environments are also integral to the project, aiming to ensure successful integration hat meets both the customer’s and Robotnik’s standards and specifications. The future vision of this project entails integrating the newly developed safety system into the company’s database for future usage and running extensive tests in diverse environments, including the customer’s infrastructure. By undertaking this project, the goal is to deliver a customized robot equipped with an advanced safety system, facilitating a safer, more adaptable, and functional mobile robotic solution.

Quality control of liquids is an important part of analytical chemistry. The gold standard for measuring residual water in organic solvents and pharmaceutical applications is Karl Fischer titration. It has a high sensitivity, selectivity and accuracy. The downsides are a time-consuming offline analysis, together with the need for toxic reagents producing waste, and it suffers from poor inter-laboratory reproducibility. In this work, we present a high-performance lab-on-a-chip sensor exploiting mid-IR spectroscopy for liquid sensing. It is operating at 6.1 mu m wavelength and is suitable for robust and flexible real-time in situ analysis of the residual water concentration in isopropyl alcohol. This is demonstrated in two experiments. A custom-made 60 mu L flow cell is employed to measure only minute amounts of analyte in an inline configuration. In a second approach, the whole sensor is immersed into the analyte to demonstrate sensitive and rapid in situ operation on the millisecond time scale. This is confirmed by the ability for time resolved single water-droplet monitoring, while they are mixed into the liquid sample. We obtain a limit of detection between 120 ppm and 150 ppm with a concentration coverage spanning three orders of magnitude from 1.2 x 10(-2)%(vol) to 25%(vol) for the flow cell and 1.5 x 10(-2)%(vol) to 19%(vol) in the in situ configuration, respectively.

Quality control of liquids is an important part of analytical chemistry. The gold standard for measuring residual water in organic solvents and pharmaceutical applications is Karl Fischer titration. It has a high sensitivity, selectivity and accuracy. The downsides are a time-consuming offline analysis, together with the need for toxic reagents producing waste, and it suffers from poor inter-laboratory reproducibility. In this work, we present a high-performance lab-on-a-chip sensor exploiting mid-IR spectroscopy for liquid sensing. It is operating at 6.1 mu m wavelength and is suitable for robust and flexible real-time in situ analysis of the residual water concentration in isopropyl alcohol. This is demonstrated in two experiments. A custom-made 60 mu L flow cell is employed to measure only minute amounts of analyte in an inline configuration. In a second approach, the whole sensor is immersed into the analyte to demonstrate sensitive and rapid in situ operation on the millisecond time scale. This is confirmed by the ability for time resolved single water-droplet monitoring, while they are mixed into the liquid sample. We obtain a limit of detection between 120 ppm and 150 ppm with a concentration coverage spanning three orders of magnitude from 1.2 x 10(-2)%(vol) to 25%(vol) for the flow cell and 1.5 x 10(-2)%(vol) to 19%(vol) in the in situ configuration, respectively.

Background: Lasers are one of the most important treatment modalities in dermatology. Lasers interact with chromophores through several mechanisms that depend on fluence and pulse durations. Early lasers worked by photothermal interaction with pulse durations of 1 microsecond to 1 second. A picosecond laser is developed to confine photothermal effects and produce photomechanical effects and plasma induction. Purpose: To understand the mechanism of action and application of picosecond lasers for dermatological disorders. Review: Non-fractional picosecond lasers work by photomechanical interaction. Photomechanical interaction happens when pulse duration is less than inertial confinement time, causing fractures of chromophores with lower energy, or “cold ablation”. Fractional picosecond lasers work by laser-induced optical breakdown (LIOB). In LIOB, accelerated seed electrons cause an electron avalanche that produce a collection of free electrons called plasma, which ablates tissues. LIOB in the skin is always followed by photodisruption. In LIOB, vacuoles and debris were eliminated transdermally and dermal collagen and elastin increased. Picosecond laser may be applied in disorders requiring destruction of chromophores and for collagen and elastin disorders. It is currently the first-line treatment for tattoo removal (Nevus of Ota and Acquired Bilateral Nevus of Ota-like macules, or ABNOM). It has good efficacy and safety for solar lentigines, freckles, and cafe-au-lait macules (CALM). It is an additional treatment for moderate to severe melasma and hypertrophic scars, in combination with other treatments. The fractional picosecond laser showed moderate improvement and low risk of postinflammatory hyperpigmentation (PIH) for atrophic acne scars and produced improvement in striae alba.

Weed control is a basic agricultural practice, typically achieved through herbicides and mechanical weeders. Because of the negative environmental impacts of these tools, alternative solutions are being developed and adopted worldwide. Following recent technical developments, an autonomous laser-based weeding system (ALWS) now offers a possible solution for sustainable weed control. However, beyond recent proof of performance, little is known about the adoption potential of such a system. This study assesses the adoption potential of ALWS, using a mixed-method approach. First, six macro-environmental factors regarding the adoption of ALWS were determined. This assessment is referred to as a Political, Economic, Social, Technological, Legal, Environmental (PESTLE) analysis and is conducted in a form of a literature review initiated by expert consultations. Second, a range of European stakeholders’ perceptions of ALWS was evaluated in four focus-group discussions (n = 55), using a strengths, weaknesses, opportunities, threats (SWOT) analysis. The factors identified in the PESTLE and SWOT analyses were subsequently merged to provide a comprehensive overview of the adoption potential of ALWS. Labour reduction, precision treatment and environmental sustainability were found to be the most important advantages of ALWS. High costs and performance uncertainty were identified as the main weaknesses. To promote the adoption of ALWS, this study recommends the following: (1) Concrete performance results, both technical and economic, should be communicated to farmers. (2) Farmers’ knowledge of precision agriculture should be improved. (3) Advantage should be taken of policies that are favourable towards non-chemical methods and the high demand for organic products. This article also extensively discusses regulatory barriers, the risks posed to the safety of both humans and the machines involved, technological challenges and requirements, and policy recommendations related to ALW

Bakalářská práce je věnována kompletnímu restaurátorskému zásahu provedeném na sousoší Nejsvětější Trojice ze sloupu z obce Opatovec na Svitavsku. Dokument obsahuje mimo jiné i umělecko-historický a chemicko-technologický průzkum, jehož součástí je rozšířená kapitola zabývající se chemickým čištěním tmavých depozitů na pískovcích se silikátovým pojivem. Porovnává čistící efekt mezi prostředky Clean FP od firmy Remmers, čističi SI a FG od firmy Aqua Barta a efekt čištění pomocí pulzního laseru. Ze všech zkoušených chemických prostředků a variant nejlépe vycházel čistič Clean FP, který byl použit i při zkouškách čištění restaurovaného díla. Dále vycházel velmi dobře čistič FG, který měl velmi podobné výsledky jako prostředek Clean FP. Nicméně pro samotné restaurování bylo rozhodnuto tyto prostředky nepoužít, ale zvolit laserové čištění. Na základě těchto průzkumů byla stanovena koncepce restaurátorského zásahu, která byla vypracována s ohledem na výsledky průzkumu, dochovaný stav památky a s respektem k autenticitě stáří. Dílo bylo zrestaurováno s maximálním respektem k jeho umělecké a historické hodnotě a tato práce obsahuje podrobnou dokumentaci všech provedených úkonů na díle. Tyto informace jsou shrnuty v postupu prací a seznamu použitých materiálů a technologií. Veškerý postup při obnově památky zahrnující i samotný průzkum je fotograficky zdokumentován., The Bachelor's thesis discusses the complete restoration treatment carried out on the group sculpture of the Holy Trinity from the village of Opatovec in the Svitavy district. The document contains, among others, art-historical and chemical-microscopy survey, which include an extended chapter dealing with the chemical cleaning of dark deposits on sandstones with silicate binder. It compares the cleaning effect of Remmers's Clean FP, Aqua Barta's SI and FG cleaners and the effect of cleaning by pulsed laser. Of all the chemical variants tested, the Clean FP cleaner performed best and was also used in the cleaning tests on the restored work. Furthermore, the FG cleaner performed very well and had similar results to Clean FP. However, it was decided not to use these products for the restoration - laser cleaning was employed instead. On the basis of these surveys, a restoration treatment plan was established, which was developed taking into account the results of the survey, the state of restoration of the monument and respecting the authenticity of its age. The artwork was restored with the utmost respect for its artistic and historical value. All the operations carried out on the work of art are recorded in detailed documentation. This information is summarised in the description of the working process and the list of materials and technologies used. All the steps of the restoration treatment, including the survey, are documented in photographs., Fakulta restaurování, Studentka formou ppt prezentace představila restaurování zadané skulptury. Reagovala na vznesené dotazy a drobné připomínky v posudcích. Vzhledem ke kvalitě provedených prací, restaurátorské dokumentace, resp. bakalářské práce, komise doporučila hodnocení "A"., Dokončená práce s úspěšnou obhajobou

Kuramitsu Yasuhiro, Sakai Kentaro, Moritaka Toseo. Electron scale magnetic reconnections in laser produced plasmas. Reviews of Modern Plasma Physics 7, 33–1 (2023); https://doi.org/10.1007/s41614-023-00125-4., Magnetic reconnection is a fundamental process in the universe, in which magnetic field energy is converted into plasma kinetic energy associated with a topological change in the magnetic field. Magnetic reconnections have been extensively investigated in space in the form of solar terrestrial plasmas, and also in laboratories in the form of magnetic confinement plasmas and laser-produced plasmas. Macroscopic features of magnetic reconnections can be well described in the context of magnetohydrodynamics (MHD) across a wide variety of research fields. However, how the kinetic regime of magnetic reconnection should be connected to the macroscopic MHD regime is still an open question. It is generally assumed that electron dynamics play an essential role in the triggering mechanism of magnetic reconnections. In this review, we discuss magnetic reconnections on the electron scale, focusing in particular on laboratory experiments using high-power lasers.

Quanteninformationsexperimente mit gefangenen 40Ca+ Ionen benötigen einen schmalbandigen Laser bei einer Wellenlänge von 729 nm zum Anregen des Qubitübergangs zwischen 42S1/2 und 32D5/2. In dieser Arbeit wird ein Titan:Saphir-Laser beschrieben, welcher bei einer Wellenlänge von 729 nm mithilfe des Pound-Drever-Hall-Verfahrens auf einen externen Resonator frequenzstabilisiert wird. Die Laserlinienbreite wurde mittels Schwebungsmessungen mit anderen frequenzstabilisierten Lasern und Ramsey-Experimenten mit einem einzelnen gefangenen 40Ca+ gemessen. Die niedrigste gemessene Linienbreite (FWHM) wurde mittels einer Schwebungsmessung erhalten und beträgt 4.2(17) Hz bei einer Messzeit von 1 s, was eine obere Grenze für die Linienbreite des Titan:Saphir-Lasers darstellt. Diese niedrigste Linienbreite wurde erreicht, nachdem eine Vibrationsisolationsplatte unter dem Resonator installiert wurde. Eine Analyse der installierten Faserrauschunterdrückung und Laserintensitätsstabilisierung legt nahe, dass Faser- und Laserintensitätsrauschen die niedrigste gemessene Linienbreite nicht limitieren. Die Schwebungsmessungen mit anderen frequenzstabilisierten Lasern wurden zusätzlich verwendet, um einen Wert für die Drift der Laserfrequenz des stabilisierten Lasers zu erhalten, und die gemessene Drift ist -371(3) mHz/s., Quantum information science experiments with trapped 40Ca+ ions require a narrow-linewidth laser at a wavelength of 729 nm to drive the qubit transition between 42S1/2 and 32D5/2. In this thesis, a Titanium:Sapphire laser is presented that is frequency-stabilized to a reference cavity at a wavelength of 729 nm using the Pound-Drever-Hall technique. The laser linewidth was measured through beat measurements with other frequency-stabilized lasers and Ramsey experiments on a single trapped 40Ca+ ion. The narrowest measured linewidth (FWHM) was obtained via a beat measurement and is 4.2(17) Hz at a measurement time of 1 s, representing an upper limit for the Titanium:Sapphire laser linewidth. This narrowest linewidth was achieved after a vibration-isolation board was installed underneath the reference cavity. An analysis of the installed fiber noise cancellation and laser intensity stabilization suggests that fiber and laser intensity noise do not limit the narrowest measured linewidth. The beat measurements with other frequency-stabilized lasers were additionally used to obtain a value for the stabilized laser’s frequency drift, which is measured to be -371(3) mHz/s., presented by Armin Winkler, Zusammenfassung in deutscher Sprache, Masterarbeit University of Innsbruck 2023

Despite the growing demand for improving smile aesthetics and occlusal functionality, a significant percentage of patients still refuse or discontinue orthodontic treatment because of pain and discomfort related to this therapy. As consequence, controlling the pain experienced by patients during the same therapy represents a primary concern for both patients and clinicians. Recent pieces of evidence have suggested that photobiomodulation can reduce pain experienced by patients during the decrowding stage or during specific protocols, for example, rapid maxillary expansion. PBM can be performed with lasers and also with a light-emitting diode (LED) device. Nonetheless, few studies on the latter are still present in the literature. The aim of this research is to evaluate the efficacy of photobiomodulation (PBM) with Laser devices in pain management in fixed orthodontic treatment. Only 14 of all articles met the inclusion and exclusion criteria and were therefore used to conduct the research. The different studies compared, in most cases, patients whose mouths were divided into a part treated with PBM and a placebo part. Most of their results show a statistically significant difference in perceived pain between the irradiated arch and the nonirradiated arch. Three authors did not find statistically significant results in favor of PBM, but they used different laser parameters. To obtain generally valid studies, with consistent and reproducible results, it is necessary to standardize the different laser parameters used. LED is less operator-dependent than laser and PBM using this technology seems to have a biological basis similar to that with lasers. In some studies, its clinical efficacy in pain reduction in some orthodontic therapies has been verified. Finally, this article aims to consider LED technology as a future prospect of research on PBM use in orthodontics.

In the entertainment industry, where temporary structures are erected in a new venue every day, floor markings play an important role during the set up. Today, mark out is commonly done using tape measures - a very tedious and time consuming process. This thesis explores the possibility to create a tool to assist in the mark out process, a mark out station. Two stations working in tandem would both compute their respective positions in the venue and accurately and precisely show the location of any wanted point, based on their coordinate locations. The mark out stations were built using consumer grade line lasers, stepper motors, common micro controllers and fused filament fabrication (FFF)-manufactured plastic components, as well as various other common hardware components. The software utilized already established triangulation algorithms and a custom control protocol to manage the mark out stations. A short range test on a test surface was performed with three different station placements. Placing the mark out stations in between three calibration points yielded better precision and accuracy in contrast to placing them on the edge of the surface. When placed on the edge, the calibration accuracy benefited from more calibration points, in contrast to placement in between calibration points. Next phase after successful short range testing is testing in a larger setting to conclude if this is a viable tool to assist in the mark out process. Further improvements in the calibration process and the mark out process can be made in future iterations to achieve better performance., Inom eventbranchen, där tillfälliga strukturer reses på nya platser varje dag, spelar markeringar på golvet en viktig roll. Idag sker utmärkningen med hjälp av måttband - en väldig tidskrävande process. Detta examnesarbete undersöker huruvida det går att utveckla ett verktyg som assisterar i denna utmärkningsprocess, en utmärkningsstation. De två stationerna som arbetar tillsammans skulle både beräkna deras respektive positioner på spelplatsen samt noggrant och precist visa placeringen av en önskad punkt, baserad på dess koordinater. Utmärkningsstationerna byggdes av konsumentlinjelasrar, stegmotorer, vanliga mikrokontrollers och FFF-tillverkade komponenter. Mjukvaran inkorporerar redan etablerade trianguleringsalgoritmer och ett egenskrivet kontrollprotokoll för att styra utmärkningsstationerna. Ett test på mindre avstånd gjordes på en testyta med tre olika stationsplaceringar. Att placera stationerna mellan tre kalibreringspunkter gav bättre noggranhet och precision än när stationerna placerades på utkanten av ytan. När stationerna placerades på utkanten av ytan, ökade noggrannheten och precisionen av att lägga till ytterligare kalibreringspunkter, till skillnad från placeringen mellan kalibreringspunkterna. Nästa fas, efter ett lyckat test på kort avstånd, är att testa på större avstånd för att undersöka om detta kan vara ett användbart vektyg inom utsättning. Ytterliggare förbättringar i kalibrerings- och utmärkningsprocessen kan göras i framtida iterationer för att uppnå en bättre prestanda.

[EU] Laserra erradiazio elektromagnetikoak sustatutako igorpenean oinarritzen den anplifikazio-optiko deritzon prozesuari esker argia igortzen duen tresna da. Teknologiaren industrian ez ezik, ikerkuntza zientifikoan eta gure eguneroko bizitzan ere laserrak izan duen izugarrizko eragina ukaezina da. Mota ezberdinetako laserrak daude, baina horien artean koloratzaile organikoak ingurune fotoaktibo gisa erabiltzen dituztenak arreta handia jasotzen ari dira azken urteotan. Laser organiko hauek erakusten dituzten emisio bandak zabalak dira. Hori dela eta sintonizagarriak dira uhin-luzera tarte zehatz batean eta pultsu ultramotzak (femtosegundutakoak) lortzea ahalbidetzen dute. Gainera gaur egun kromoforo zerrenda luzea dago eskuragarri, koloratzaileen artean aukeratzeko euren banden kokapenaren arabera tarte zabalean, ultramoretik ikusgaira edo infragorri hurbilera. Horien artean, BODIPY izeneko koloratzaileek arrakasta izugarria eduki dute argiak zuzendutako gailuetan, baita laserretan ere. Bere kromoforoak absortzio eta emisio banda ahaltsuak emateaz gain, erraz eraldatu daiteke hainbat prozesu sintetikoen bidez. Hori dela eta, molekula-egitura borondatez aldatu daiteke hainbat talde funtzional txertatuz eta, bide batez, horren ezaugarri fotofisikoak modulatu. Lan honetan, BODIPY komertzialen ezaugarri fotofisikoak, elektrokimikoak eta laser erradiazioa aztertuko dira. Informazio esperimentala osatzeko, kimika konputazionala erabiliko da kalkulu mekanokuantikoen bidez. Baliabide teoriko-esperimental hauetaz baliatuz molekula egiturak laser igorpenaren kokapenean, eraginkortasunean eta fotoegonkortasunean duen eragina ulertzea bilatzen da. Izan ere, parametro hauek agintzen dute laser portaera. Beraz, BODIPY egituran ordezkatzaile desberdinak lotzean agertzen diren aldaketak argiak sustatzen dituen prozesu fotofisikoetan aztertzea eta ulertzea ezinbestekoa da ez soilik laser portaera azaltzeko baizik eta koloratzaile hobetuak diseinatzeko ere.

El present document és un descripció detallada d’un projecte d’enginyeria, on es dissenya i es construeix una màquina làser per a gravar i tallar diferents materials. Es tracte d’un treball complex i variat perquè inclou parts de disseny assistit per ordinador, muntatges, realització de quadros elèctrics i programació. En aquest treball de fi d’estudis es troba descrit pas a pas i de forma detallada tots aquells camins que s’han seguit per a aconseguir assolir l’objectiu, la construcció de la màquina làser. El document inicia amb la descripció de l’activitat, tot seguit es troba una petita introducció teòrica a les màquines CNC, i s’explica el funcionament d’un làser. La part pràctica del treball comença amb el disseny de la màquina, realitzat amb un programa anomenat SolidWorks, una eina de disseny assistit per ordinador que permet crear i modelar peces en 3D. I acaba amb l’explicació del codi, la configuració final de la màquina i la posada en marxa. A més a més s’ha calculat un pressupost detallat de tots els costos, on es pot observar el cost final del projecte, i també s’han realitzat els plànols de totes aquelles peces que han estat dissenyades únicament per a la màquina làser., El presente documento es una descripción detallada de un proyecto de ingeniería, donde se diseña y se construye una máquina láser para grabar y cortar diferentes materiales. Se trata de un trabajo complejo y variado porque incluye partes de diseño asistido por ordenador, montajes, realización de cuadros eléctricos y programación. En este trabajo de fin de estudios se encuentra descrito paso a paso y de forma detallada todos aquellos caminos que se han seguido para conseguir el objetivo, la construcción de la máquina láser. El documento inicia con la descripción de la actividad, seguidamente se encuentra una pequeña introducción teórica a las máquinas CNC, y se explica el funcionamiento de un láser. La parte práctica del trabajo empieza con el diseño de la máquina, realizado con un programa llamado SolidWorks, una herramienta de diseño asistido por ordenador que permite crear i modelar piezas en 3D. Y termina con la explicación del código, la configuración final de la máquina y la puesta en marcha. Además, se ha calculado un presupuesto detallado de todos los costes, donde se puede observar el coste final del proyecto, y también se han realizado los planos de todas aquellas piezas que han estado diseñadas únicamente para la máquina láser., This document is a detailed description of an engineering project, where a laser machine is designed and built to engrave and cut different materials. It is a complex and varied work because it includes parts of computer-aided design, assemblies, electrical panels and programming. In this end-of-study project, all those paths that have been followed to achieve the objective, the construction of the laser machine, are described step by step and in detail. The document begins with the description of the activity, followed by a short theoretical introduction to CNC machines, and the operation of a laser is explained. The practical part of the work begins with the design of the machine, carried out with a program called SolidWorks, a computer-aided design tool that allows you to create and model parts in 3D. And it ends with the explanation of the code, the final configuration of the machine and the first start-up. In addition, a detailed budget of all the costs has been calculated, where the final cost of the project can be observed, and also there are the plans of all those parts that have been designed only for the laser machine have also been made.

Drug delivery systems have the potential to deliver high concentrations of drug to target areas on demand, while elsewhere and at other times encapsulating the drug, to limit unwanted actions. Here we show proof of concept in vivo and ex vivo tests of a novel drug delivery system based on hollow-gold nanoparticles tethered to liposomes (HGN-liposomes), which become transiently permeable when activated by optical or acoustic stimulation. We show that laser or ultrasound simulation of HGN-liposomes loaded with the GABAA receptor agonist, muscimol, triggers rapid and repeatable release in a sufficient concentration to inhibit neurons and suppress seizure activity. In particular, laser-stimulated release of muscimol from previously injected HGN-liposomes caused subsecond hyperpolarizations of the membrane potential of hippocampal pyramidal neurons, measured by whole cell intracellular recordings with patch electrodes. In hippocampal slices and hippocampal–entorhinal cortical wedges, seizure activity was immediately suppressed by muscimol release from HGN-liposomes triggered by laser or ultrasound pulses. After intravenous injection of HGN-liposomes in whole anesthetized rats, ultrasound stimulation applied to the brain through the dura attenuated the seizure activity induced by pentylenetetrazol. Ultrasound alone, or HGN-liposomes without ultrasound stimulation, had no effect. Intracerebrally-injected HGN-liposomes containing kainic acid retained their contents for at least one week, without damage to surrounding tissue. Thus, we demonstrate the feasibility of precise temporal control over exposure of neurons to the drug, potentially enabling therapeutic effects without continuous exposure. For future application, studies on the pharmacokinetics, pharmacodynamics, and toxicity of HGN-liposomes and their constituents, together with improved methods of targeting, are needed, to determine the utility and safety of the technology in humans., source:https://www.mdpi.com/1999-4923/14/2/468

In this dissertation, I investigate the possibility of lasing and nonlinear phenomena in completely solid-state transverse Anderson localizing optical fibers (TALOFs). I examine three areas within this range of topics. The research in nonlinear phenomena focuses on four-wave mixing (FWM). FWM is of high interest in TALOFs due to the fact that guided localized modes of the fiber each have different propagation constants, and thus unique possible FWM pairs can be generated from the same input pump beam. I demonstrate the generation of FWM in the TALOF by pumping it with 532 nm light into a localized mode and observing Stokes and anti-Stokes peaks at a 330 cm^-1 spectral shift with respect to the pump. I also study the laser gain properties of the ytterbium-doped TALOF (Yb:TALOF). I present a modified cutback method that allowed me to determine the coupling efficiency, resonant absorption, and saturation power of a 975 nm pump beam. With this information I initially determined that the fiber was incapable of lasing if pumped with 975 nm light, but should be capable of lasing when pumped with 915 nm light. In the last chapter, I perform two cutback measurements at 1065 nm and 915 nm. We find that the background absorption at 1065 nm is an order of magnitude lower than at 633 nm, indicating that Rayleigh scattering may have a significant contribution to the background attenuation in the fiber. Therefore, we go through and reassess our calculations of the previous chapter using a corrected value of background absorption scaled by wavelength to the fourth power. We find that this correction provides a much more accurate prediction when calculating parameters of the fiber. This chapter concludes with the amplification of 1030 nm and 1065 nm light when pumped with a 915 nm light source. During amplification, localization of of the signal beam is observed.

Monolithic semiconductor lasers including edge-emitting lasers (EELs) and vertical-cavity surface-emitting lasers (VCSELs) fail to realize simultaneous achievement of both high-power high-quality beams due to intrinsic limitations of their resonant cavity. Photonic crystal surface emitting lasers (PCSELs) address these structural limitations through employment of a two-dimensional photonic crystal (PC) cavity that creates feedback at a single wavelength for laterally scalable devices. This function of the PC allows PCSELs to power scale with area while maintaining single-mode emission required for diffraction-limited beams. In this way, PCSELs fulfill an industry demand for high-power high-quality lasing from a single chip. Early PCSELs were fabricated by way of wafer fusion where two wafers, the first containing the active layer and the second containing the PC, are joined together via heat treatment in a liquid phase epitaxy furnace. This technique produces a high density of light absorbing defects at the bonded interface. Modern PCSEL fabrication forgoes wafer bonding in favor of processes that maintain crystalline order throughout the entire structure. This work demonstrates PCSEL fabrication by epitaxial regrowth and single- epitaxy methods to illustrate their respective advantages and engineering challenges. While specific properties of epitaxial regrowth are beneficial for total output power, a single-epitaxy process simplifies fabrication and provides a more scalable and wavelength versatile platform. PCSELs with InGaAs multiple-quantum-well (MQW) active regions are constructed by molecular beam epitaxy (MBE) using both regrowth and single-epitaxy methods. Total output power of epitaxially regrown PCSELs is dramatically improved by implementation of a flip-chip bonding process and a metal- organic chemical vapor deposition (MOCVD) regrowth step. By affecting stable large- area coherent lasing, the fabricated PCSELs described in this work address th

The rate of energy transfer between electrons and phonons is investigated by a first principles framework for electron temperatures up to $T_e=50000$~K while considering the lattice at ground state. Two typical but differently complex metals are investigated, namely Aluminium and Copper. In order to reasonably take the electronic excitation effect into account, we adopt finite temperature density functional theory and linear response to determine the electron-temperature-dependent Eliashberg function and electron density of states. Of the three branch-dependent electron-phonon coupling strengths, the longitudinal acoustic mode plays a dominant role in the electron-phonon coupling for Aluminium for all temperatures considered here, but for Copper it only dominates above an electron temperature of $T_e=40000$~K. The second moment of the Eliashberg function and the electron phonon coupling constant at room temperature $T_e=315$~K show good agreement with other results. For increasing electron temperatures, we show the limits of the $T=0$ approximation for the Eliashberg function. Our present work provides a rich perspective on the phonon dynamics and this will help to improve insight into the underlying mechanism of energy flow in ultra-fast laser-metal interaction.

The influence of a transverse magnetic field on the formation and evolution of supersonic plasma jets and shocks was studied experimentally, and compared with 3D numerical simulations. An improved jet collimation was seen due to the change in the magnetic field topology restricting the radial expansion of the ablated plasma. The magnetic field was also shown to strongly affect the shock structures, both indirectly through the modified jet geometry, as well as due to a compression of the field lines in the shock region. The interaction characteristics were found to depend on the relative contribution of the magnetic and plasma pressure in balancing the ram pressure of the jet.

The Hybrid Collaboration, a joint undertaking by HZDR, DESY, University of Strathclyde, LMU, and LOA, performed hybrid LPWFA experiments which utilize electron bunches from a laser wakefield accelerator (LWFA) as drivers of a plasma wakefield stage (PWFA) to demonstrate the feasibility of compact PWFAs serving as a test bed for the efficient investigation and optimization of PWFAs and their development into brightness boosters. To better understand the microscopic, nonlinear dynamic of these accelerators, the experiments were accompanied by 3D3V particle-in-cell simulations using PIConGPU. Here, we present insights into the dynamics of the hybrid LPWFA that we gained from start-to-end simulations of the experimental setup at HZDR. These regard electron injections due to hydrodynamic shocks, beam self-modulation and breakup, and cavity elongation - all backed-up by synthetic diagnostics that allow direct comparison with experimental measurements. We discuss our approach to model these synthetic diagnostics directly within the PIConGPU simulation as well as modelling certain aspects of the experimental setup, such as the drive laser. Continuing this, the talk highlights a few recent technical advances in PIConGPU that enable better modelling of the micro-physics, experiment conditions, or signals of experiment diagnostics.

Motivated by recent experimental initiatives, such as at the Helmholtz International Beamline for Extreme Fields (HIBEF) at the European X-ray Free Electron Laser (XFEL), we calculate the birefringent scattering of x-rays at the combined field of two optical (or near-optical) lasers and compare various scenarios. % In order to facilitate an experimental detection of quantum vacuum diffraction and birefringence, special emphasis is placed on scenarios where the initial and final x-ray photons differ not just in polarization, but also in propagation direction (corresponding to scattering angles in the mrad regime) and possibly energy.

DFT data and results for Al and Cu for the DOS, phonon DOS, and Eliashberg function depending on the electron temperature.

Introducción: La disfonía es un trastorno caracterizado por la alteración de la voz, pudiendo ser debida a diversas causas orgánicas o funcionales de la laringe. Entre las posibilidades diagnósticas, una vez descartada malignidad, se encuentran entidades como la papilomatosis, las lesiones vasculares, la displasia, la queratosis o las leucoplasias. La terapia láser se considera uno de los pilares fundamentales en el tratamiento de este tipo de lesiones, siendo una opción el láser de colorante pulsado de 585-nm. Su mecanismo de acción se basa en el principio de fototermólisis selectiva, cuyo blanco de acción es la hemoglobina. Objetivo: Realizar una revisión sistemática sobre la eficacia y seguridad del tratamiento con láser de colorante pulsado de 585-nm en lesiones no malignas de laringe. Métodos: Tres autores buscaron artículos publicados en PubMed/MEDLINE, la Biblioteca Cochrane, Google Scholar, Scielo y Web of Science sobre el procedimiento. Se analizaron los criterios de inclusión, exclusión y diagnóstico, así como la evaluación de los resultados clínicos de los estudios incluidos mediante los criterios PRISMA. El análisis de sesgos se evaluó con la herramienta NICE Public Health Guidance. Resultados: Un total de 26 publicaciones fueron seleccionadas. El láser de colorante pulsado de 585-nm presenta, como se objetiva en los estudios incluidos, un amplio abanico de indicaciones: lesiones vasculares, papilomatosis, leucoplasia, displasia, queratosis, granulomas, cicatrices, laringitis criptocóccica y edema de Reinke. Independientemente de la lesión en cuestión, la tolerancia del procedimiento bajo anestesia local es excepcional y los resultados en términos de regresión y calidad vocal son prometedores. Asimismo, las complicaciones asociadas son mínimas y dicho procedimiento no interfiere en la ejecución de otras alternativas de tratamiento como la cirugía, si fuesen necesarias. No hay consenso sobre los parámetros láser a utilizar. Conclusión: Pese a la necesidad, Introdución: A disfonía é un trastorno caracterizado pola alteración da voz, que pode ser debido a diversas causas orgánicas ou funcionais da larinxe. Entre as posibilidades diagnósticas, unha vez descartada malignidade, encóntranse entidades como a papilomatose, as lesións vasculares, a displasia, a queratose ou as leucoplasias. A terapia láser considérase un dos pilares fundamentais no tratamento deste tipo de lesións, sendo unha opción o láser de colorante pulsado de 585-nm. O seu mecanismo de acción fundaméntase no principio da fototermolise selectiva, cuxo branco de acción é a hemoglobina. Obxectivo: Realizar unha revisión sistemática sobre a eficacia e a seguridade do tratamento co láser de colorante pulsado de 585-nm en lesións non malignas de larinxe. Métodos: Tres autores buscaron artículos publicados en PubMed/MEDLINE, a Biblioteca Cochrane, Google Scholar, Scielo e Web of Science sobre o procedemento. Analizáronse os criterios de inlcusión, exclusión e diagnóstico así coma a avaliación dos resultados clínicos dos estudios incluidos mediante os criterios PRISMA. A análise de sesgos foi avaliada coa ferramenta NICE Public Health Guidance. Resultados: Un total de 26 publicacións foron seleccionadas. O láser de colorante pulsado de 585-nm presenta, como se obxectiva nos estudos incluidos, un amplio abanico de indicacións: lesión vasculares, papilomatose, leucoplasia, displasia, queratose, granulomas, cicatrices, larinxite criptocóccica e edema de Reinke. Independentemente da lesión en cuestión, a tolerancia do procedemento baixo anestesia local é excepcional e os resultados en términos de regresión e calidade vocal son prometedores. Do mesmo modo, as complicacións asociadas son mínimas e dito procedemento non interfire na execución doutras alternativas de tratamento coma a cirurxía, se fosen necesarias. Non hai consenso referente ós parámetros láser a utilizar. Conclusións: Pese a necesidade de futuros estudios, a día de hoxe o láser de colorante pulsado de 5, Introduction: Dysphonia is a disorder characterized by the alteration of the voice, which may be due to various organic or functional causes of the larynx. Among the diagnostic possibilities, once malignancy is ruled out, are entities such as papillomatosis, vascular lesions, dysplasia, keratosis or leukoplakia. Laser therapy is considered one of the fundamental pillars in the treatment of this type of lesions, being an option the 585-nm pulsed dye laser. Its mechanism of action is based on the principle of selective photothermolysis, whose target is hemoglobin. Objective: To evaluate the efficacy and safety of 585-nm pulsed dye laser procedures for treatment of non-malignant laryngeal lesions. Methods: Three authors searched for articles published in PubMed/MEDLINE, the Cochrane Library, Google Scholar, Scielo, and Web of Science about the procedure. Inclusion, exclusion and diagnosis criteria were analysed as well as the assessment of the clinical outcomes of the included studies using the PRISMA. Results: A total of 26 publications were selected. The 585-nm pulsed dye laser presents, as objective in the included studies, a wide range of indications: vascular lesions, papillomatosis, leukoplakia, dysplasia, keratosis, granulomas, scars, cryptococcal laryngitis and Reinke edema. Regardless of the lesion, the tolerance of the procedure under local anesthesia is exceptional and the results in terms of regression and vocal quality are promising. The complication rate is minimal and the procedure does not interfere with other treatment alternatives such as surgery if it is necessary. There is not consensus on laser settings to use. Conclusion: Despite the need for future studies, today the 585-nm pulsed dye laser is an effective and safe therapeutic option that give us the opportunity to give back the voice to those patients with non-malignant laryngeal pathology