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It is known from medical practise that patients and physicians can have positive experiences with little-researched and unapproved interventions. Under certain circumstances, effects even go beyond the placebo effect.Based on casuistics of chronic pain patients, the question of whether self-medication in the context of a good doctor-patient relationship can optimize the efficacy of cannabinoids and reduce dose and undesirable side effects is investigated. Using medicinal cannabis as an example, a new view on self-medication and medical support is proposed.The casuistics show that daily requirements (average of approximately 75 mg) for ΔIf the patient has "discovered" cannabis as medicine for himself and can draw on positive experiences, something very powerful can emerge. In addition to the specific effects demonstrated by studies, there are non-specific effects or contextual factors at work that tend to be neglected in evidence-based medicine. These non-specific effects include, above all, those factors through which a patient gives a (subjective) meaning to a specific intervention. A new view on self-medication and medical support in chronic diseases is needed.Hintergrund: Erfahrungsmedizinisch bekannt ist, dass Patienten und Ärzte positive Erfahrungen mit nur wenig erforschten und nicht zugelassenen Interventionen machen können. Dabei gehen Wirkungen unter bestimmten Umständen über den Placeboeffekt hinaus.Ausgehend von Kasuistiken chronischer Schmerzpatienten wird der Frage nachgegangen, ob durch Selbstmedikation im Kontext einer vertrauensvollen Arzt-Patienten-Beziehung die Wirksamkeit von Cannabinoiden optimiert werden kann und sich Dosis sowie unerwünschte Nebenwirkungen reduzieren lassen. Am Beispiel von Medizinalcannabis wird eine neue Sicht auf Selbstmedikation und ärztliche Begleitung vorgeschlagen.Ergebnisse: Die Erfahrungen aus den Kasuistiken zeigen, dass sich der tägliche Bedarf (durchschnittlich ca. 75 mg) an Tetrahydrocannabinol(THC)-Dosen reduzieren lässt. Eine unbegleitete und risikoreiche Selbstmedikation kann in eine effektive Therapie mit deutlich weniger Medizinalcannabis transformiert werden. Die Vorgehensweise besteht darin, die bis dato stattgefundene Selbstmedikation nachzuvollziehen und den Patienten dort abzuholen, wo er selber für sich etwas "entdeckt" hat. Erklären lässt sich die spezifische Wirkweise von Cannabis bei chronischen Erkrankungen über die Mechanismen im Endocannabinoidsystem. Cannabinoide entlasten Patienten im Kontext von Stress, Angst und Depression, die bei chronischen Erkrankungen immer beteiligt sind. In ihrem körperlichen sowie psychischen Empfinden werden Patienten gestärkt und schließlich in die Selbstwirksamkeit geführt.Schlussfolgerungen: Hat der Patient "Cannabis als Medizin" selbst für sich "entdeckt" und kann auf positive Erfahrungen zurückgreifen, so kann etwas sehr Wirkmächtiges entstehen. Neben den spezifischen Effekten, die durch Studien nachgewiesen werden, wirken unspezifische Effekte bzw. Kontextfaktoren, die in der evidenzbasierten Medizin eher vernachlässigt werden. Zu diesen unspezifischen Effekten gehören vor allem solche Faktoren, durch die ein Patient einem Wirkmittel eine (subjektive) Bedeutung gibt. Eine neue Sicht auf Selbstmedikation und ärztliche Begleitung bei chronischen Erkrankungen ist erforderlich.Schlüsselwörter: Cannabinoide, Selbstmedikation, Endocannabinoidsystem, Placeboanalgesie, ValeboEingereicht am 12.8.2021 - Revision akzeptiert am 17.1.2022.

Ion microscopy is an established technique for laser focus diagnostics and the accurate, intensity-resolved measurement of laser ionization processes. In the present feasibility study, we discuss a new ion microscope design, which improves its resolution across a large range of magnifications and simplifies its operation. Instead of the common two einzel lens configuration, which is usually optimized for a fixed magnification, we propose a generic design consisting of an array of equally spaced ring electrodes, whose individually adjustable voltages are controlled by an evolutionary algorithm. In this way, we can realize aberration minimized magnifications between 25 and 100. Moreover, the algorithm can adjust the voltage settings under changing experimental conditions and facilitates autofocusing for user-defined magnification.

ZusammenfassungDie Sprache ist eines der wichtigsten Medien im zwischenmenschlichen Miteinander. Vor dem Hintergrund, dass es in unserem Gesundheitssystem v. a. um messbare und abrechenbare Größen geht, wird die Bedeutung des Gesprächs und der Sprache eher vernachlässigt. In Patientenumfragen hat sich oft gezeigt, dass gerade das Gespräch zwischen Arzt und Patient eine sehr hohe Priorität für kranke Menschen hat. Sprache und Kommunikation haben nicht nur bei der Patientenzufriedenheit und Compliance einen hohen Stellenwert, sondern auch bei der Anamnese und Diagnose bis hin zur Therapie, Pflege und Sterbebegleitung. Sprache und Kommunikation werden zudem als eigener Wirkfaktor für den Behandlungserfolg unterschätzt.Der Artikel fasst die Bedeutung dieser Zusammenhänge zusammen, gibt praktische Beispiele und einen Ausblick, wo praktische Hilfen verfügbar sind.

The notion of therapeutic communication was spread mainly by Paul Watzlawick. He is building on antique roots and argues that the working principles are known since the antique and were wide spread in the art of healing. The famous statement of the sophist Antiphon from Athena »I can heal the sick with words« Watzlawick explains in the context of rhetoric and he refers explicitly to the »somatic rhetoric« of Quinitilian and his Instituto Oratoria. For a better understanding of this statement the Socratic art of speech will be introduced practically, which shows itself in contrast to the rhetoric of sophism: as talk room of truth in opposition to a talk room of method. Even the giving of a remedy is indispensably connected with the dialog between the physician and the patient and only in this combination a catharsis is enabled. The working principles of the therapeutic communication relate to all areas of rhetoric, that means not only inventio, dispositio and elocutio but also actio and pronuntatio as well as the whole context of speech.

The interpretation of experimental data from novel mid-infrared few-cycle laser sources requires an understanding of ionization mechanisms and knowledge about related ion yields. Experimental studies have indicated sequential double ionization as the dominant process above 1014 W cm−2. These results contradict a recent prediction that in this spectral region, non-sequential processes dominate the double ionization of xenon up to intensities of about 1015 W cm−2. In either case, the ratio of doubly to singly charged xenon yield reported in previous studies has been limited to a few percent, indicating a regime well below the onset of saturation of the double ionization process. We present an experimental study of double ionization of xenon and krypton atoms exposed to intense near four-cycle pulses at 3.2 μm. Our experiments rely on the ion microscopy technique, which facilitates the detection of ions originating from a restricted region within the interaction volume, thereby reducing the impact of focal averaging. Our measurements suggest that at intensities of close to 1.2 × 1014 W cm−2, double ionization of xenon and krypton is already significantly saturated. In particular, we find a doubly to singly charged yield ratio of about 75 percent for xenon and 25 percent for krypton. We compare our results with the predictions of different models accounting for the effects of volume averaging and focal geometry. We find that in the deeply saturated regime of our experiment, the Perelomov–Popov–Terentyev theory significantly underestimates the observed double ionization yield.

Das Nocebo gilt als der „bose Bruder“ des Placebos, da es sich um unerwunschte Wirkungen handelt. Eng gefasst meint der Begriff negative Effekte bei Teilnehmern von Arzneimittelstudien, die zur Placebogruppe gehoren. Dennoch lassen sich die gleichen Nebenwirkungen beobachten, die vom Ve­rum verursacht werden konnten. Weit gefasst bedeutet Nocebo die Verursachung von Symptomen durch die Erwartung von Symptomen und damit verbundene Gefuhlszustande. Noceboeffekte gehoren zum klinischen Alltag, sind bislang aber nur wenig erforscht. Zur Vermeidung spielt die Arzt-Patienten-Kommunikation eine entscheidende Rolle.

We demonstrate multiphoton ionization of inner-shell electrons in Xenon with 100-eV attosecond pulses. This was achieved with a novel XUV source based on high-harmonic generation in the gas phase driven with multi-TW few-cycle laser pulses.

Nonlinear light-matter interactions in the extreme ultraviolet (XUV) are a prerequisite to perform XUV-pump/XUV-probe spectroscopy of core electrons. Such interactions are now routinely investigate ...

Nonlinear photoionization with energetic FEL pulses has opened up new horizons for the investigation of inner-shell electron dynamics in atomic and molecular systems [1]. So far, however, the limited temporal resolution (typically a few tens of femtoseconds) achievable with FELs has hampered the time resolution of these dynamics.

We report on the generation of high-order harmonics in gas media using a sub-5 fs multi-ten-terawatt laser system. The application of this source towards XUV-pump/XUV-probe experiments with photon energies around 100 eV is discussed.

Journal of optics 20(2), 024018 (2018). doi:10.1088/2040-8986/aaa326, The development of ultra-short intense laser sources in the visible and extreme ultraviolet (XUV) spectral range has led to fascinating studies in laser-matter interactions and attosecond science. In the majority of these studies, the system under investigation interacts with a focused light beam, which ionizes the system. The ionization products are usually measured by devices, which spatiotemporally integrate the ionization signal originating from the entire focal area, discarding in this way valuable information about the ionization dynamics that take place in the interaction volume. Here, we review a recently developed approach in measuring the spatially resolved photoionization yields resulting from the interaction of infrared (IR)/XUV ultra-short light pulses in gas phase media. We show how this approach enables (a) the in situ focus diagnostic, (b) quantitative studies of linear and non-linear ionization processes in the IR/XUV regime, (c) single-shot XUV-pump-XUV-probe studies and (d) single-shot 2nd-order XUV autocorrelation measurements., Published by IOP Publ., Bristol

Wie Miniatur-Schneeballe wirken neutrale Cluster aus einigen tausend Molekulen: Treffen sie mit ausreichender Geschwindigkeit auf eine Oberflache, so konnen sie von dieser Biomolekule wie Insulin ablosen. Weil die Cluster wahrend und nach dem Aufprall auseinanderbrechen und verdampfen, stehen nach diesem mikroskopischen Schneeballwurf „nackte“ Biomolekulionen fur massenspektrometrische Studien zur Verfugung.

We demonstrate a tool for quantitative measurements in the extreme ultraviolet (EUV) spectral region measuring spatially resolved atomic ionization products at the focus of an EUV beam. The ionizing radiation is a comb of the 11th–15th harmonics of a Ti:Sapphire femtosecond laser beam produced in a Xenon gas jet. The spatial ion distribution at the focus of the harmonics is recorded using an ion microscope. Spatially resolved single- and two-photon ionization products of Argon and Helium are observed. From such ion distributions single- and two-photon generalized cross sections can be extracted by a self-calibrating method. The observation of spatially resolved two-EUV-photon ionization constitutes an initial step towards future single-shot temporal characterization of attosecond pulses.

We report a new approach to intense-field photoionization that is based on the ad hoc assumption that m photons of energy $E_{\rm ph}$ arriving within a typical electronic response time are effectively equivalent to a single photon of energy $mE_{\rm ph}$ . The heuristic model contains no adjustable parameters and unifies apparent multiphoton and field aspects. Moreover, nonsequential, suppressed and above-threshold ionization phenomena become readily understandable. Predicted ionization intensities are in satisfactory agreement with available experimental data ranging from C6H6 to Ne3 + , from femtosecond to nanosecond laser pulses, and from ultraviolet to infrared laser radiation.

Cluster impact induced charge separation was studied with neat and mixed clusters of SO2 and H2O impinging at hyperthermal velocities on a SiOx target held at different temperatures. At 750 K, impact of SO2 clusters produces positively and negatively charged cluster fragments of the form [(SO2)n − K, Na] + and [(SO2)m − SO2] − which is explained in terms of the known cluster-impact induced pickup of alkali surface adsorbates. The high sensitivity of this channel promises applications for the analysis of alkali surface contaminations. The dominant fragments observed during the impact of binary SO2/H2O clusters at the same target temperature were [(H2O)n − H] + and [(SO2)p (H2O)q − HSO3] − , which indicates an intracluster proton transfer reaction. Similar fragments were also detected as minor spectral progressions during the surface impact of neat SO2 clusters at a target temperature of 380 K. This is interpreted in terms of an impact-induced pickup of water surface adsorbates into the neat sulfur dioxide cluster during the surface collision. Upon impact of neat water clusters, fragment ions of the form [(H2O)n − H] + and [(H2O)q − OH] − are observed, which can be explained in terms of the autoprotolysis reaction in bulk water.

The fragmentation dynamics of (H2O)1032 clusters colliding with a repulsive surface at incident velocities of 1753 m/s and 2909 m/s, corresponding to kinetic energies of 0.5 and 1.5 times the cluster binding energy, has been examined in a classical molecular dynamics simulations study. The results show a large anisotropy in the energy redistribution inside the cluster upon impact, which leads to asymmetric fragmentation, starting in the leading part of the cluster. The low-mass region of the fragment size distribution can be described by a power law with an exponent close to −1.6, and the range of this region increases with increasing incident velocity. The formed fragments have rather uniform internal temperatures close to the standard boiling point of water, but the translational energy of the monomers formed upon collision is much larger, pointing at the asymmetric energy distribution inside the cluster. The angular distributions of fragment mass and fragment kinetic energy peak at grazing exit angles....

Intense isolated attosecond pulses with >100 eV photon energy are produced via high-order-harmonic generation using 80mJ sub-5 fs laser pulses. The generation of these attosecond pulses and their application to non-linear XUV-XUV pum-probe experiments is discussed.

The tunnelling of an electron through a suppressed atomic potential followed by its motion in the continuum, is the fundamental mechanism underlying strong-field laser-atom/molecule interactions. Due to its quantum nature, the interaction is governed by the phase of the released electron wave-packets. Thus, detailed mapping of the electron wave-packet interferences provides essential insight into the physics underlying the interaction. A process which is providing access to the intricacies of the interaction is the generation of high order harmonics of the laser frequency. The phase-amplitude distribution of the emitted extreme-ultraviolet (EUV), carries the complete information about the harmonic generation process and vice-versa. Thus, the visualization of the EUV-spatial-amplitude-distribution, as it results from interfering electron wave-packet contributions, is of crucial importance. Restrictions to this accomplishment are due to the spatially integrating measurement approaches applied so far, that average out the phase effects in the generation process. In this work, we demonstrate a method which overcomes this obstacle. An EUV-spatial-amplitude-distribution-image is induced from the imprint on the measured spatial distribution of ions, produced through EUV-photon ionization of atoms. Interference extremes in the image carry phase information about the interfering electron wave-packets. The present approach provides detailed insight on the strong-field laser-atom interaction mechanism, while establishing the era of phase selective interaction studies. Furthermore, it paves the way for substantial enhancement of the spectral and temporal precision of measurements by in-situ controlling the phase distribution of the emitted radiation and/or spatially selecting the EUV-radiation-atom interaction products., Comment: 13 pages main text with 4 figures, 7 pages supporting material with 3 figures

In this paper we present an approach to equalize multipath transmitted video signals without any reference signal. This approach takes advantage of the constant envelope feature of the color burst signal, which is transmitted in the blanking interval of each TV line and can be considered as an angle-modulated signal. The constant modulus algorithm (CMA) after Treichler is modified for our purpose. Special attention is given to the equalization of video signals in PAL systems. By making full use of the genuine phase feature of the color burst signal in PAL systems, the Hilbert transform needed by CMA can be saved for equalizing PAL system video signals. In addition to equalize analog TV signal, this paper can also lead to a joint echo cancellation of analog and digital TV signals transmitted in cable network.

The observation that clusters of neutral H2O () or SO2 (ref. 5) molecules, on impact with essentially any solid surface, can decay efficiently into positively and negatively charged fragments has defied explanation, not least because the kinetic energy per molecule can be much smaller than the molecular ionization potentials. Here we present a microscopic model of the charging mechanism, based on a mass analysis of charged SO2 cluster fragments, which appears to be applicable to polar-molecule clusters more generally. Our mass spectra reveal that all positively charged fragments carry an alkali ion (sodium, potassium or caesium), whereas the negative fragments are simply (SO2)n−. The yields of both charged species are comparable, and can be enhanced significantly by pre-treating the sample surface with additional alkali atoms. The key to charge separation in the clusters therefore appears to be the pickup of a neutral (but readily ionized) adatom during impact, followed by delocalization of the adatom's valence electron within the cluster and the subsequent collision-induced fragmentation of the cluster into charged pieces. This process could be of practical use in, for example, charge-pair generation and surface analysis; it may also be relevant to atmospheric ionization processes.

The operation principle and the performance of a variable-volume selective TOF mass spectrometer are discussed in detail. Lateral confinement is achieved with an appropriate entrance aperture. Width and location of the axial confinement are established via the energy filtering capacity of a newly developed five-grid ion mirror. The minimum dimensions are in the μm range. The thus defined detection volume ΔV , can be scanned through a laser beam. Complete ionization of target gases such as SO 2 and Xe within ΔV , permits calibration of the overall detection sensitivity. This instrument can be utilized to measure spatially resolved ion concentrations, absolute ionization probabilities and the intensity dependence of ion yields which are not affected by volume expansion. As an example we investigate optical field ionization of water with a Ti:Sa laser at intensities up to 10 16 W/cm 2 . Published by Elsevier Science B.V.

∗University of Nebraska Lincoln, cuiterwaal2@unl.edu †Foundation for Research and Technology–Hellas, Institute of Electronic Structure & Laser, Laser and Applications Division, GR-711 10 Heraklion, Crete, Greece ‡Foundation for Research and Technology–Hellas, Institute of Electronic Structure & Laser, Laser and Applications Division, GR-711 10 Heraklion, Crete, Greece ∗∗Max-Planck-Institut fur Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany ††Max-Planck-Institut fur Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany ‡‡Max-Planck-Institut fur Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching, Germany This paper is posted at DigitalCommons@University of Nebraska Lincoln.

A simple method for the determination of saturation intensities and in some cases generalized cross sections in multiphoton ionization is presented. It utilizes the dependence of the ponderomotive shift on the laser intensity above the saturation limit. An application to He and Ar interacting with 500 fs pulses at 248 nm is demonstrated. Experimental results are compared with theoretical calculations.

Auf die Bedeutung der Erziehungs- und Bildungspartnerschaft zwischen Erziehungsberechtigten, ErzieherInnen und LehrerInnen wurde schon in vorangegangenen Kapiteln hingewiesen. Auch ihre gesetzliche Verankerung wurde hinreichend aufgezeigt (vgl. Grundgesetz, Art. 6 und 7). Die Forderung nach einer Erziehungskontinuitat, welche eine erfolgreiche LehrerInnen- Eltern-Kooperation voraussetzt, begrundet sich vom Kind her aus dessen Anspruch auf eine erfolgversprechende Schulausbildung (GG Art. 2 Abs. 1).

Erziehungsberechtigte, ErzieherInnen in Kindertagesstatten und LehrerInnen mussen eine Erziehungspartnerschaft eingehen, um die Personlichkeitsentwicklung kontinuierlich zu fordern. Gegensatze im Erziehungsprozess konnen zu Bruchen in der Entwicklung fuhren.

Through a theoretical analysis combined with new experimental data, obtained through a technique that allows observation of ionization originating from a constant, sharply limited ion extraction volume, we show that double multiphoton ionization of Xe and Kr in the wavelength range 527 to 531 nm does not involve an observable direct two-electron channel but does involve an inner subshell (5s for Xe and 4s for Kr) excited state which can leave the ion in an excited state. This explains the unusual laser power dependence that had been attributed to a direct two-electron channel.

We present experimental results for the ionization of aniline and benzene molecules subjected to intense ultrashort laser pulses. Measured parent molecular ions yields were obtained using a recently developed technique capable of three-dimensional imaging of ion distributions within the focus of a laser beam. By selecting ions originating from the central region of the focus, where the spatial intensity distribution is nearly uniform, volumetric-free intensity-dependent ionization yields were obtained. The measured data revealed a previously unseen resonance-enhanced multiphoton ionization (REMPI)-like process. Comparison of benzene, aniline, and Xe ion yields demonstrates that the observed intensity-dependent structures are not due to geometric artifacts in the focus. Finally for intensities greater than {approx}3x10{sup 13} W/cm{sup 2}, we attribute the ionization of aniline to a stepwise process going through the {pi}{sigma}{sup *} state which sits three photons above the ground state and two photons below the continuum.

Handling input content ranging from low resolution and highly compressed internet streams up to high definition video is a challenging task for modern flat panel TVs. Considering that the consumer is accustomed to HD content, superior processing is mandatory especially for low bit-rate video with very low quality. In this paper, we describe a novel spatio-temporal and image content adaptive regularization algorithm, which can deal with this entire content well. This algorithm can significantly improve the video quality, remove spatial and temporal artifacts and even re-establish missing details. The spatio-temporal regularization combines the well-known Total Variation image model with a novel temporal constraint, being robust towards erroneous motion vectors and allowing application of block based motion estimation techniques.

Laser wakefield accelerators have shown 1 GeV electron beams with some 10 pC charge from centimeter-length gas capillaries. The electrons are accelerated by the field of a plasma wave trailing an intense laser pulse. For improving the stability, electron injection and acceleration should be separated. One possible scheme is self-injection with a plasma density gradient and subsequent acceleration at constant density. This can be realized by embedding a high-density gas jet into a capillary. A critical parameter for this scheme to work is the realization of a specific density gradient, therefore a robust measurement is desirable. A new method utilizing the density dependence of Raman scattering has been used to characterize the high-density region of a neutral gas within a capillary with a few ten micrometer longitudinal resolution. This allowed us to measure a density drop of a factor of 4 within 200 micrometers.