670 research outputs found
17-jähriger Mann mit akuten Bauchschmerzen, Hämatochezie und Exanthem
Zusammenfassung: Ein 17-jähriger Patient stellte sich mit kolikartigen abdominellen Schmerzen und Diarrhö vor. Als weitere Symptome traten Petechien, Arthralgien und eine Hämatochezie auf. Sonographisch bestand eine auffällige Ileozökalregion. Endoskopisch fand sich eine Ileitis terminalis, und histologisch zeigte sich hier eine leukozytoklastische Vaskulitis mit IgA-Ablagerungen. Die Kasuistik zeigt exemplarisch die mehrzeitige klinische Manifestation der Purpura Schönlein-Henoch und deren Verlau
Do Irrelevant Sounds Impair the Maintenance of All Characteristics of Speech in Memory?
Several studies have shown that maintaining in memory some attributes of speech, such as the content or pitch of an interlocutor's message, is markedly reduced in the presence of background sounds made of spectrotemporal variations. However, experimental paradigms showing this interference have only focused on one attribute of speech at a time, and thus differ from real-life situations in which several attributes have to be memorized and maintained simultaneously. It is possible that the interference is even greater in such a case and can occur for a broader range of background sounds. We developed a paradigm in which participants had to maintain the content, pitch and speaker size of auditorily presented speech information and used various auditory distractors to generate interference. We found that only distractors with spectrotemporal variations impaired the detection, which shows that similar interference mechanisms occur whether there are one or more speech attributes to maintain in memory. A high percentage of false alarms was observed with these distractors, suggesting that spectrotemporal variations not only weaken but also modify the information maintained in memory. Lastly, we found that participants were unaware of the interference. These results are similar to those observed in the visual modalit
From Quantum Universal Enveloping Algebras to Quantum Algebras
The ``local'' structure of a quantum group G_q is currently considered to be
an infinite-dimensional object: the corresponding quantum universal enveloping
algebra U_q(g), which is a Hopf algebra deformation of the universal enveloping
algebra of a n-dimensional Lie algebra g=Lie(G). However, we show how, by
starting from the generators of the underlying Lie bialgebra (g,\delta), the
analyticity in the deformation parameter(s) allows us to determine in a unique
way a set of n ``almost primitive'' basic objects in U_q(g), that could be
properly called the ``quantum algebra generators''. So, the analytical
prolongation (g_q,\Delta) of the Lie bialgebra (g,\delta) is proposed as the
appropriate local structure of G_q. Besides, as in this way (g,\delta) and
U_q(g) are shown to be in one-to-one correspondence, the classification of
quantum groups is reduced to the classification of Lie bialgebras. The su_q(2)
and su_q(3) cases are explicitly elaborated.Comment: 16 pages, 0 figures, LaTeX fil
Spatio-Temporal Pattern of Saturn's Equatorial Oscillation
Recent ground-based and Cassini CIRS thermal-infrared data have characterized the spatial and temporal characteristics of an equatorial oscillation in the middle atmosphere of Saturn above the 100-mbar level. The CIRS data [I] indicated a pattern of warm and cold anomalies near the equator, stacked vertically in alternating fashion. The ground-based observations s2, although not having the altitude range or vertical resolution of the CIRS observations, covered several years and indicated an oscillation cycle of approx.15 years, roughly half of Saturn's year. In Earth's middle atmosphere, both the quasi-biennial (approx.26 months) and semi-annual equatorial oscillations have been extensively observed and studied (see e.g., [3]), These exhibit a pattern of alternating warmer and cooler zonal-mean temperatures with altitude, relative to those at subtropical latitudes. Consistent with the thermal wind equation, this is also associated with an alternating pattern of westerly and easterly zonal winds. Moreover, the pattern of winds and temperatures descends with time. Momentum deposition by damped vertically propagating waves is thought to play a key role m forcing both types of oscillation, and it can plausibly account for the descent. Here we report the direct observation of this descent in Saturn's equatorial atmosphere from Cassini radio occultation soundings in 2005 and 2009. The retrieved temperatures are consistent with a descent of 0.7 x the pressure scale height. The descent rate is related to the magnitude of the wave forcing, radiative damping, and induced meridional circulations. We discuss possible implications
Saturn's Equatorial Oscillation: Evidence of Descending Thermal Structure from Cassini Radio Occultations
Ground-based and Cassini CIRS thermal-infrared data have characterized the spatial and temporal characteristics of an equatorial oscillation in Saturn's middle atmosphere above the 100-mbar level. The CIRS data indicate a vertical pattern of alternating warm and cold anomalies at the equator. From the thermal wind equation this implies a concomitant reversal of zonal winds with attitude, relative to the cloud-top winds, with peak-to-peak amplitude approximately 200 meters per second. The ground-based observations do not having the altitude range or vertical resolution of the CIRS observations, but they cover several years and indicate an oscillation cycle of 1 years, roughly half of Saturn's year. Equatorial oscillations in Earth's middle atmosphere have primarily exhibited either quasi-biennial or semi-annual "periodicities," and both types have been extensively observed and modeled. They exhibit a vertical pattern of alternating warmer and cooler zonal-mean temperatures and zonal winds analogous to that described above for Saturn. Moreover, the pattern of winds and temperatures descends with time. Momentum deposition by damped vertically propagating easterly and westerly waves is thought to play a key role in forcing both types of oscillation, and it can plausibly account for the descent. Here we report the direct observation of this descent in Saturn's equatorial atmosphere from Cassini radio occultation soundings in 2005 and 2009. The retrieved temperatures are consistent with a descent of 0.6 x the pressure scale height over this time period. The descent rate is related to the magnitude of the wave forcing, radiative damping, and induced meridional circulations. A simple calculation implies that vertical wave fluxes of zonal momentum approximately 0.05 square meters per square second could account for the observed vertical descent on Saturn, which is comparable to the magnitude of the wave fluxes associated with the terrestrial quasi-biennial oscillation
Three dimensional quantum algebras: a Cartan-like point of view
A perturbative quantization procedure for Lie bialgebras is introduced and
used to classify all three dimensional complex quantum algebras compatible with
a given coproduct. The role of elements of the quantum universal enveloping
algebra that, analogously to generators in Lie algebras, have a distinguished
type of coproduct is discussed, and the relevance of a symmetrical basis in the
universal enveloping algebra stressed. New quantizations of three dimensional
solvable algebras, relevant for possible physical applications for their
simplicity, are obtained and all already known related results recovered. Our
results give a quantization of all existing three dimensional Lie algebras and
reproduce, in the classical limit, the most relevant sector of the complete
classification for real three dimensional Lie bialgebra structures given by X.
Gomez in J. Math. Phys. Vol. 41. (2000) 4939.Comment: LaTeX, 15 page
A novel multivariate STeady-state index during general ANesthesia (STAN)
The assessment of the adequacy of general anesthesia for surgery, namely the nociception/anti-nociception balance, has received wide attention from the scientific community. Monitoring systems based on the frontal EEG/EMG, or autonomic state reactions (e.g. heart rate and blood pressure) have been developed aiming to objectively assess this balance. In this study a new multivariate indicator of patients' steady-state during anesthesia (STAN) is proposed, based on wavelet analysis of signals linked to noxious activation. A clinical protocol was designed to analyze precise noxious stimuli (laryngoscopy/intubation, tetanic, and incision), under three different analgesic doses; patients were randomized to receive either remifentanil 2.0, 3.0 or 4.0 ng/ml. ECG, PPG, BP, BIS, EMG and [Formula: see text] were continuously recorded. ECG, PPG and BP were processed to extract beat-to-beat information, and [Formula: see text] curve used to estimate the respiration rate. A combined steady-state index based on wavelet analysis of these variables, was applied and compared between the three study groups and stimuli (Wilcoxon signed ranks, Kruskal-Wallis and Mann-Whitney tests). Following institutional approval and signing the informed consent thirty four patients were enrolled in this study (3 excluded due to signal loss during data collection). The BIS index of the EEG, frontal EMG, heart rate, BP, and PPG wave amplitude changed in response to different noxious stimuli. Laryngoscopy/intubation was the stimulus with the more pronounced response [Formula: see text]. These variables were used in the construction of the combined index STAN; STAN responded adequately to noxious stimuli, with a more pronounced response to laryngoscopy/intubation (18.5-43.1 %, [Formula: see text]), and the attenuation provided by the analgesic, detecting steady-state periods in the different physiological signals analyzed (approximately 50 % of the total study time). A new multivariate approach for the assessment of the patient steady-state during general anesthesia was developed. The proposed wavelet based multivariate index responds adequately to different noxious stimuli, and attenuation provided by the analgesic in a dose-dependent manner for each stimulus analyzed in this study.The first author was supported by a scholarship from the Portuguese Foundation for Science and Technology (FCT SFRH/BD/35879/2007). The authors would also like to acknowledge the support of UISPA—System Integration and Process Automation Unit—Part of the LAETA (Associated Laboratory of Energy,
Transports and Aeronautics) a I&D Unit of the Foundation for Science and Technology (FCT), Portugal. FCT support under project PEst-OE/EME/LA0022/2013.info:eu-repo/semantics/publishedVersio
Licensed to Kill: The Battle between Patent and Antitrust in Monopoly Leveraging Cases
This note puts a new spin on a longstanding subject of scholarship and controversy in the law: the conflict between the patent and antitrust laws in the United States. The author examines this conflict in the context of monopoly leveraging cases. Since patents are a unique and powerful tool that companies use to gain advantage in the marketplace, they seem to allow the owner to engage in behavior which amounts to monopoly leveraging. However, such conduct is prohibited under the antitrust laws, specifically by Section 2 of the Sherman Act. If a patent exists to give its owner certain commercial rights and advantages, how can the owner\u27s use of these powers be simultaneously proscribed by another body of law? This note looks at this inherent conflict and how courts have sought to deal with it. Looking at the Ninth Circuit\u27s treatment of this very problem in the Kodak II case, the note argues that although there is a facial conflict between patent and antitrust, a meaningful look at the policies and goal underlying the two bodies of law allows for a reconciliation between the two
Licensed to Kill: The Battle between Patent and Antitrust in Monopoly Leveraging Cases
This note puts a new spin on a longstanding subject of scholarship and controversy in the law: the conflict between the patent and antitrust laws in the United States. The author examines this conflict in the context of monopoly leveraging cases. Since patents are a unique and powerful tool that companies use to gain advantage in the marketplace, they seem to allow the owner to engage in behavior which amounts to monopoly leveraging. However, such conduct is prohibited under the antitrust laws, specifically by Section 2 of the Sherman Act. If a patent exists to give its owner certain commercial rights and advantages, how can the owner\u27s use of these powers be simultaneously proscribed by another body of law? This note looks at this inherent conflict and how courts have sought to deal with it. Looking at the Ninth Circuit\u27s treatment of this very problem in the Kodak II case, the note argues that although there is a facial conflict between patent and antitrust, a meaningful look at the policies and goal underlying the two bodies of law allows for a reconciliation between the two
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