Brachytherapie im Vergleich mit Mikrowellenablation, Radiofrequenzablation und Leberresektion bei der Behandlung des hepatozellulären Karzinoms: Auswertung ausgewählter veröffentlichter Studien

Zur Behandlung des hepatozellulären Karzinoms stehen neben der Leberresektion verschiedene interventionelle radiologische Therapieverfahren zur Verfügung, welche besonders bei nicht resektablen Tumoren zum Einsatz kommen. Zu diesen Verfahren zählen die Mikrowellenablation, die Radiofrequenzablation und die Brachytherapie. Da nach aktueller Studienlage keine klare Aussage darüber gemacht werden kann, ob BT den anderen Therapieverfahren in Hinblick auf den Hazard-Wert bzw. die momentane Sterberate und den Hazard Ratio über-/unterlegen oder gleichzusetzen ist, ist es das Ziel dieser Arbeit der Beantwortung dieser Frage näher zu kommen. Es wurden insgesamt 36 Studien zu BT, MWA, RFA und LR ausgewertet und miteinander verglichen. Die einzelnen Hazard-Werte sowie die gesamt Hazard-Werte wurden berechnet und die Hazard Ratios gebildet. Die verschiedenen Studien wurden anhand der Hazard Ratios indirekt miteinander verglichen. Darüber hinaus wurden Durchschnittswerte von weiteren Parametern wie Tumorgröße und Alter der Patienten berechnet und mit in die Diskussion einbezogen. Das Ergebnis zeigt höhere gesamt Hazard-Werte (BT: 0,66; MWA: 0,175; RFA: 0,201; LR: 0,253) und schlechtere Hazard Ratios (BT/MWA: 3,77; BT/RFA: 3,28; BT/LR: 2,61) bei der BT im Vergleich zu den anderen Therapieverfahren, die aber wahrscheinlich eher darauf zurückzuführen sind, dass die Gruppe der mit BT behandelten Patienten in mehreren Punkten einen durchschnittlich schlechteren Gesundheitszustand hatte als die mit MWA, RFA und LR behandelten Patientengruppen. Außerdem standen zur Brachytherapie die wenigsten Studien zur Verfügung (BT: 3, MWA: 8; RFA: 19; LR: 6 Studien). Brachytherapie kann also nicht grundsätzlich als den anderen Methoden unterlegen dargestellt werden

Учет влияния времени коммутации полупроводниковых приборов на форму импульсов напряжения на нагрузке импульсного трансформаторного источника напряжения

Розглянутo вплив часу комутації напівпровідникових приладів на форму, амплітудні і часові параметри імпульсів напруги на навантаженні трансформаторного джерела. Встановлена залежність тривалості фронту імпульсу від власних параметрів джерела і часу комутації напівпро-відникових приладів.Influence of time of commutation of semiconductor devices is considered on a form, peak and temporal parameters of pulses of voltage in a load of transformer source. Dependence of duration of pulse front is set on the own parameters of source and time of commutation of semiconductor devices

EEG Microstates During Resting Represent Personality Differences

We investigated the spontaneous brain electric activity of 13 skeptics and 16 believers in paranormal phenomena; they were university students assessed with a self-report scale about paranormal beliefs. 33-channel EEG recordings during no-task resting were processed as sequences of momentary potential distribution maps. Based on the maps at peak times of Global Field Power, the sequences were parsed into segments of quasi-stable potential distribution, the ‘microstates'. The microstates were clustered into four classes of map topographies (A-D). Analysis of the microstate parameters time coverage, occurrence frequency and duration as well as the temporal sequence (syntax) of the microstate classes revealed significant differences: Believers had a higher coverage and occurrence of class B, tended to decreased coverage and occurrence of class C, and showed a predominant sequence of microstate concatenations from A to C to B to A that was reversed in skeptics (A to B to C to A). Microstates of different topographies, putative "atoms of thought”, are hypothesized to represent different types of information processing.The study demonstrates that personality differences can be detected in resting EEG microstate parameters and microstate syntax. Microstate analysis yielded no conclusive evidence for the hypothesized relation between paranormal belief and schizophreni

MODELLING TECHNICAL SYSTEMS IN THE EARLY PHASE: PROPOSING A FORMAL DEFINITION FOR THE SYSTEM CONCEPT

The task of developing “concepts” is common in all fields of engineering, especially in the early phases of product development. However, an in-depth literature analysis showed that authors - often depending on different contexts in design research, education, and industry - define the term “concept” in differing ways. The aspect of reference-based development is rarely addressed in existing definitions. This indicates that there is a need for an updated and concise concept definition. In this paper, the authors propose a new definition of the term “system concept” within the context of SGE - System Generation Engineering that incorporates the findings from the literature analysis. The definition was reflected on in two case-studies. The first one contained the system concept for automotive display and operating systems, the second one the system concept for a kinesthetic-haptic VR interface. The proposed definition contains the relevant characteristics identified from the literature review and supports both current activity-based process models and reference-based development, as practical application has shown

Investigating Mobile Device-Based Interaction Techniques for Collocated Merging

In mixed-focus collaboration, group members create content both individually as a kind of groundwork for discussion and further processing as well as directly together in group work sessions. In case of individual creation, separate documents and contents need to be merged to receive an overall solution. In our work, we focus on mixed-focus collaboration using mobile devices, especially smartphones, to create and merge content. Instead of using emails or messenger services to share content within a group, we describe three different mobile device-based interaction techniques for merging that use built-in sensors to enable ad-hoc collaboration and that are easy and eyes-free to perform. We conducted a user study to investigate these merging interactions. Overall, 21 participants tested the interactions and evaluated task load and User Experience (UX) of the proposed device-based interactions. Furthermore, they compared the interactions with a common way to share content, namely writing an email to send attached content. Participants gave valuable user feedback and stated that our merging interaction techniques were much easier to perform. Furthermore, we found that they were much faster, less demanding, and had a greater UX than email

Telecom-Band SPDC in AlGaAs-on-Insulator Waveguides

Widespread commercial adoption of telecom-band quantum-key-distribution (QKD) will require fully integrated, room-temperature transmitters. Implementing highly efficient spontaneous parametric down-conversion (SPDC) on a platform that offers co-integration of the pump laser has been an outstanding challenge. Here, using such a platform based on AlGaAs-on-insulator waveguides, we report telecom-band SPDC (and second harmonic generation) with exceedingly large efficiencies of 26 GHz generated pairs/mW over a 7 THz bandwidth, which would saturate the usable photon-flux for a 70-channel wavelength-multiplexed QKD-system at merely 1.6 mW of pump laser power

Formation of hard VHE gamma-ray spectra of blazars due to internal photon-photon absorption

The energy spectra of TeV gamma-rays from blazars, after being corrected for intergalatic absorption in the Extragalactic Background Light (EBL), appear unusually hard, a fact that poses challenges to the conventional models of particle acceleration in TeV blazars and/or to the EBL models. In this paper we show that the internal absorption of gamma-rays caused by interactions with dense narrow-band radiation fields in the vicinity of compact gamma-ray production regions can lead to the formation of gamma-ray spectra of an almost arbitrary hardness. This allows significant relaxation of the current tight constraints on particle acceleration and radiation models, although at the expense of enhanced requirements to the available nonthermal energy budget. The latter, however, is not a critical issue, as long as it can be largely compensated by the Doppler boosting, assuming very large ($\geq 30$) Doppler factors of the relativistically moving gamma-ray production regions. The suggested scenario of formation of hard gamma-ray spectra predicts detectable synchrotron radiation of secondary electron-positron pairs which might require a revision of the current ``standard paradigm'' of spectral energy distributions of gamma-ray blazars. If the primary gamma-rays are of hadronic origin related to $pp$ or $p \gamma$ interactions, the ``internal gamma-ray absorption'' model predicts neutrino fluxes close to the detection threshold of the next generation high energy neutrino detectors.Comment: 10 pages, 8 figures, submitted to MNRA

Empirical Legal Studies Before 1940: A Bibliographic Essay

The modern empirical legal studies movement has well-known antecedents in the law and society and law and economics traditions of the latter half of the 20th century. Less well known is the body of empirical research on legal phenomena from the period prior to World War II. This paper is an extensive bibliographic essay that surveys the English language empirical legal research from approximately 1940 and earlier. The essay is arranged around the themes in the research: criminal justice, civil justice (general studies of civil litigation, auto accident litigation and compensation, divorce, small claims, jurisdiction and procedure, civil juries), debt and bankruptcy, banking, appellate courts, legal needs, legal profession (including legal education), and judicial staffing and selection. Accompanying the essay is an extensive bibliography of research articles, books, and reports