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Ultrafast electron dynamics drive phenomena such as photochemical reactions, catalysis, and light harvesting. To capture such dynamics in real-time, femtosecond to attosecond light sources are extensively used. However, an exact match between the excitation photon energy and a characteristic resonance is crucial. High-harmonic generation sources are advantageous in terms of pulse duration but limited in spectral tunability in the vacuum ultraviolet range. Here, we present a monochromatic femtosecond source continuously tunable around 21eV photon energy utilizing the second harmonic of an optical parametric chirped pulse amplification laser system to drive high-harmonic generation. The unique tunability of the source is verified in an experiment probing the interatomic Coulombic decay in doped He nanodroplets across the He absorption bands. Moreover, we achieved intensities sufficient for driving collective processes in multiply excited helium nanodroplets, which have been previously observed only at free electron lasers.
Overview of FLASHlab@PITZ: the new R&D platform for FLASH radiation therapy and radiation biology
(2024)
An R&D platform for electron FLASH radiation therapy and radiation biology is being prepared at the Photo Injector Test facility at DESY in Zeuthen (FLASHlab@PITZ). This platform is based on the unique beam parameters available at PITZ: ps scale electron bunches of up to 22 MeV with up to 5 nC bunch charge at MHz bunch repetition rate in bunch trains of up to 1 ms in length repeating at 1 to 10 Hz. It works together with the Technical University of Applied Sciences Wildau (TH Wildau) as partner in close vicinity for the biological resources.
A startup beamline has been installed to allow dosimetry studies and irradiation experiments on chemical, biochemical and biological samples after a 60-degree dispersive arm. The measured dose and dose rates under different beam conditions and first experimental results will be reported in this paper. In addition, a dedicated beamline for FLASHlab@PITZhas been designed for better control of the high brightness electron beams. This includes a dogleg to translate the beam and a 2D kicker system to scan the tiny beam focused by quadrupoles across the samples within less than 1 ms. Simulation studies will be presented to demonstrate the extremely flexible dose parameters with various irradiation options for electron FLASH radiation therapy and radiation biology studies.
The rise of Fe magnetic moment, changes in Al electronic structure and a variation of Al magnetic polarization in thin films of transition metal aluminide Fe60Al40 have been probed through the order-disorder phase transition by soft X-ray absorption spectroscopy and X-ray resonant magnetic reflectivity in the extreme ultraviolet regime. In a course of the transition induced by 20 keV Ne+ irradiation with low fluences (1014 ions·cm-2), X-ray magnetic circular dichroism spectra taken at the Fe L2,3 absorption edges at room and low temperatures revealed a pronounced increase of Fe 3d states spin-polarization. X-ray resonant magnetic reflectivity applied to the Al L2,3 and Fe M2,3 edges allowed to detect the magnetic polarization of Al atoms in the films. The changes in Al electronic structure have been seen by alteration of Al K edge X-ray absorption near edge structure. A difference in anisotropy fields for films before and after irradiation has been observed by element-specific hysteresis loops recorded at low temperatures in absorption and reflection geometries at the Fe L2,3 and M2,3 edges, respectively. An attempt to reduce the top oxide layer by an inductively coupled hydrogen plasma has shown a possibility to recover the chemically ordered phase.
Dieser Beitrag beschreibt zwei Studien zur Akzeptanz eines Messroboters zur Durchführung von dermatologischen In-Vivo-Messungen. Die erste Studie ist eine quantitative Online-Umfrage mit 745 Teilnehmern. Die Studie gliedert sich in drei Bereiche mit insgesamt 24 Fragen. Die Teilnehmer werden zu ihren Erfahrungen und Ängsten in Bezug auf Roboter befragt und insbesondere zu einem möglichen Einsatz eines Messroboters für dermatologische In-Vivo-Studien. Für die qualitative Studie werden insgesamt 17 Studienteilnehmer jeweils einzeln für ein zweistündiges Interview, welches in 4 Phasen gegliedert ist, eingeladen. In Phase 2 dieser Studie werden die ersten robotergestützten In-Vivo-Messungen an Hautarealen auf dem Unterarm der Teilnehmer durchgeführt. Bereits aus der quantitativen Umfrage geht hervor das die meisten (75 %) Teilnehmer der Idee von Robotern im Messbetrieb offen gegenüber stehen, 55,7% befürworten den Einsatz sogar. Während des quantitativen Interviews werden Ängste und Unsicherheiten vor und während der ersten Messung genannt und beobachtet. Alle Teilnehmer waren zur Wiederholungsmessung sehr viel sicherer im Umgang mit dem Roboter und können sich einen zukünftigen Einsatz vorstellen. Besondere Herausforderungen stellen sich hinsichtlich der Positionierung der Studienteilnehmer zum Roboter heraus. Die Sicherstellung einer ergonomischen Gestaltung der Roboterumgebung ist für physische Mensch-Roboter-Kollaboration entscheidend und wird zur Weiterentwicklung des Systems stärker berücksichtigt. Weiter wurde ein 3-Stufen-Zustimmschalter zur Absicherung der Roboterbewegungen verwendet, dieser fand allerdings wenig Anklang und wurde stark kritisiert. Für den zukünftigen Einsatz wird eine alternative Überwachung des direkten Arbeitsbereiches erarbeitet.
Synthetic substances like many pharmaceuticals, preservatives or other chemical compounds are actually very difficult to handle in sewage treatment. These compounds are very stable in aqueous solution and their degradation reactions are insufficient. Therefore, to eliminate these substances from wastewater additional afford is necessary. Extreme conditions like pH value, redox potential, chemical or physical energy need to be present. With our study we try to show that the use of plasma discharge could be a solution to this problem. Using the example of methylparaben, a preservative, we could show, that the physical energy of plasma discharge is able to initialize the degradation reaction in aqueous environment. The concentration was reduced by up to 70 percent in our setting depending on the treatment duration. Overall, the system showed potential to optimize wastewater treatment. Further examinations are necessary for example regarding undesirable by-products.
Dieses Paper präsentiert das Forschungsprojekt „Intelligent Camera Unit“ (ICU) der Technischen Hochschule Wildau in Kooperation mit der Beiersdorf AG zur Verbesserung von Portraitaufnahmen in Probandenstudien für Kosmetikprodukte. Das Hauptziel des Projekt besteht darin, Ausrichtungsfehler zu minimieren und die Vergleichbarkeit von Vorher-Nachher-Bildern zu erhöhen. Dies wird durch die Verwendung eines kollaborativen Roboters und KI-gestützter Bildanalyse erreicht, um präzise Ausrichtung und Gesichtspositionen der Probanden zu gewährleisten. Das entwickelte System ermöglicht effiziente und reproduzierbare Aufnahmen aus verschiedenen Winkeln und Entfernungen und bietet eine benutzerfreundliche, web-basierte Bedienoberfläche.
Der technische Fortschritt hat dazu geführt, dass die Kosten für das automatisierte Drucken von Emblemen, Anhängern sowie allgemein gedruckten Prototypen stark gefallen sind. Dies geschah insbesondere auch vor dem Hintergrund eines Wandels der Industrie hin zu einer modernen Industrie 4.0. In dieser Arbeit wird ein neuer Ansatz für das automatische 3D-Drucken eines Logos präsentiert, welches als Pixelgrafik vorliegt. Die vorgeschlagene Prozesskette erzeugt hierbei final den G-code zum Drucken. Dabei sind seitens des Users wenige Eingaben erforderlich.
The object of the study is the process of identifying the state of a computer network. The subject of the study are the methods of identifying the state of computer networks. The purpose of the paper is to improve the efficacy of intrusion detection in computer networks by developing a method based on transformer models. The results obtained. The work analyzes traditional machine learning algorithms, deep learning methods and considers the advantages of using transformer models. A method for detecting intrusions in computer networks is proposed. This method differs from known approaches by utilizing the Vision Transformer for Small-size Datasets (ViTSD) deep learning algorithm. The method incorporates procedures to reduce the correlation of input data and transform data into a specific format required for model operations. The developed methods are implemented using Python and the GOOGLE COLAB cloud service with Jupyter Notebook. Conclusions. Experiments confirmed the efficiency of the proposed method. The use of the developed method based on the ViTSD algorithm and the data preprocessing procedure increases the model's accuracy to 98.7%. This makes it possible to recommend it for practical use, in order to improve the accuracy of identifying the state of a computer system.
The application of a biocompatible polymer nanocarrier can provide target delivery to tumor tissues, improved pharmacokinetics, controlled drug release, etc. Therefore, the proposed strategy was to use the water-soluble star-like copolymers with a Dextran core and Poly(N-isopropylacrylamide) grafts (D-g-PNIPAM) for conjugation with the widely used chemotherapy drugs in oncology–Cisplatin (Cis-Pt) and Doxorubicin (Dox). The molecular characteristics of the copolymer were received using size-exclusion chromatography. The physicochemical characterization of the D-g-PNIPAM-Cis-Pt (or Dox) nanosystem was conducted using dynamic light scattering and FTIR spectroscopy. Using traditional biochemical methods, a comparative analysis of the enhancement of the cytotoxic effect of free Cis-Pt and Dox in combination with D-g-PNIPAM copolymers was performed in cancer cells of the Lewis lung carcinoma line, which are both sensitive and resistant to Dox; in addition, the mechanism of their action in vitro was evaluated.
The MAC end-station at the ELI Beamlines facility is a multipurpose user's station for atomic, molecular, and optical sciences and coherent diffractive imaging. The technical design of the station, the available instruments, and an overview of the whole beamline have been published in Eur. Phys. J. Spec. Top. 230, 4183 (2021). Here, we address ongoing upgrades of the MAC end-station that will provide users with advanced capabilities for beam manipulation and electron/ion detection. The upgrades include (i) the installation of a beam preparation chamber in front of the MAC chamber, (ii) a magnetic bottle electron spectrometer with high collection and detection efficiency and high energy resolution, and (iii) an event-driven TPX3CAM detector for velocity map imaging spectrometer, which provides both spatial and temporal information for each pixel. We present results from the first commissioning measurements with these instruments, confirming their performance for state-of-the-art experiments in atomic, molecular, and optical sciences.