Interchange for Joint Research Entitled: Measurement of Stable Nitrogen and Sulfur Isotopes

Viking measurements of the Martian atmosphere indicate a value of N-15/N-14 which is markedly greater than that found in Earth's atmosphere. These isotopic measurements provide a powerful diagnostic tool which may be used to derive valuable information regarding the past history of Mars and they have been used to place important constraints on the evolution of Mars' atmosphere. Initial partial pressures of nitrogen, outgassing rates, and integrated deposition of nitrogen into minerals have been calculated from this important atmospheric data (McElroy et al., 1976 and 1977; Fox and Dalgarno, 1983). The greater precision obtained in laser spectrometer isotopic measurements compared to the Viking data will greatly improve these calculated values. It has also been proposed that the N-15/N-14 value in Mars' atmosphere has increased monotonically over time (McElroy et al., 1977; Fox and Dalgarno, 1983; Wallis, 1989) owing to preferential escape of atmospheric 14N to space. Nitrogen isotopic ratios might be used to identify relatively ancient crustal rocks (R. Mancinelli, personal communication), and perhaps determine relative aces of surface samples. As a first step in successfully measuring nitrogen isotopes optically we have demonstrated the measurement of 15NI14N to a precision of 0.1% (See Figures 1-4) using a tunable diode laser and an available gas (N-,O) with spectral lines in the 2188 cm-1 region. The sample and reference gas cells contained gases of identical isotopic composition so that the 15NI14N absorption ratio determined from the sample cell, when divided by the 15NI14N absorption ratio determined from the reference cell, should yield an ideal value of unity. The average measured value of this "ratio of ratios" was 0.9983 with a standard deviation (20 values) of 0.0010. This corresponds to a precision of 0.1% (1 per mil) for nitrogen isotopes, a value sufficiently precise to provide important isotopic data of interest to exobiologists. The precision presently attainable in gases is sufficient to permit the instrument to be used in the measurement of isotopic ratios of interest to exobiologists as well as geologists and planetary scientists

Monitoring of Time-Dependent System Profiles by Multiplex Gas Chromatography with Maximum Entropy Demodulation

The maximum entropy technique was successfully applied to the deconvolution of overlapped chromatographic peaks. An algorithm was written in which the chromatogram was represented as a vector of sample concentrations multiplied by a peak shape matrix. Simulation results demonstrated that there is a trade off between the detector noise and peak resolution in the sense that an increase of the noise level reduced the peak separation that could be recovered by the maximum entropy method. Real data originated from a sample storage column was also deconvoluted using maximum entropy. Deconvolution is useful in this type of system because the conservation of time dependent profiles depends on the band spreading processes in the chromatographic column, which might smooth out the finer details in the concentration profile. The method was also applied to the deconvolution of previously interpretted Pioneer Venus chromatograms. It was found in this case that the correct choice of peak shape function was critical to the sensitivity of maximum entropy in the reconstruction of these chromatograms

Brexit: Negotiation phase and scenarios of a drama in three acts

Brussels and London are gearing up for the Brexit negotiations. Prime Minister Theresa May delivered her Brexit speech and the Supreme Court ruled that the UK Parliament has to give its assent. The British government is still planning to declare that the UK intends to leave the EU by the end of March 2017. But how will the Brexit negotiations unfold? Valentin Kreilinger, Sophia Becker and Laura Maria Wolfstädter systematize the next steps in the process and examine the individual procedural requirements in order to analyse the legal and institutional context of Article 50 TEU

Einfluss der Temperatur auf die Lungenfunktionsparameter im Rahmen der isolierten hyperthermen Lungenperfusion

Ziel der vorliegenden Arbeit war, den Einfluss der Temperatur auf das normale Lungengewebe im Rahmen der isolierten hyperthermen Lungenperfusion am Schweinemodell zu untersuchen. Zur Beurteilung dienten hämodynamische und ventilatorische Parameter. Als Ergebnis der Studie zeigte sich deutlich die Überlegenheit der isolierten hyperthermen Lungenperfusion mit 41,5 °C

Frühes kognitives Defizit nach interventioneller Aortenklappenimplantation

Die Therapie der Aortenklappenstenose mittels transfemoraler Aortenklappenim-plantation rückt in der letzten Zeit zunehmend in den Fokus. Dies gilt nicht nur, da dieses Vitium das häufigste Erworbene des Erwachsenen darstellt, sondern besonders, da die betroffenen Patienten häufig multiple Begleiterkrankungen aufweisen, die die konventionelle Therapie obsolet werden lassen. Hierdurch wird TAVI zur Therapie der Wahl bei Patienten mit einem exorbitant hohem peri- und post-operativem Risikoprofil. Dies sowohl im Hinblick auf die Mortalität als auch die - oft bereits prä-interventionell eingeschränkte - kognitive Leistungsfähigkeit. Dies ist die erste Studie die zeigt, dass bemerkenswerter Weise über 90 % der untersuchten Patienten keine signifikante Verschlechterung der kognitiven Leistungsfähigkeit im frühen Intervall nach TAVI präsentieren. Sowohl eine prä-interventionelle Niereninsuffizienz als auch eine komplizierte Prozedur scheinen vergesellschaftet mit dem Auftreten eines kognitiven Defizits nach TAVI. Trotz hoher Embolielast post-prozedural konnte kein Zusammenhang von kognitiver Leistungsfähigkeit und morphologischem Korrelat im dw-MRT aufgezeigt werden. Direkte randomisierte Vergleiche mit dem konventionellen Aortenklappenersatz sowie Langzeitdaten stehen noch aus. Besonders im Hinblick auf die denkbare Ausweitung der Indikationsstellung hin zu einem jüngeren Patientenkollektiv erscheinen diese von Interesse

The Public\u27s Perception of an Earthquake Early Warning System: A Study on Factors Influencing Continuance Intention

This paper investigates the perceptions of the New Zealand public towards the Android Earthquake Alert (AEA) system, a public-facing earthquake early warning system. Specifically, it examines the public’s continuance intention towards the AEA system and the influencing factors of satisfaction, confirmation, perceived usefulness, and perceived trust. To gather insights into the public’s perceptions regarding the AEA system, this study distributed online surveys following two separate earthquake alert events on 12 October and 22 October 2021. A total of 524 and 671 participants responded to the two events’ surveys, providing valuable data for analysis and exploration. Structural Equation Modelling of the two datasets revealed that the continuance model fit the data to some extent, especially on the significance of perceived usefulness and perceived trust to continuance intention. However, the results also showed varying results for satisfaction’s relationship with perceived trust and continuance intention. These findings underscore the need for further investigation into the role of satisfaction and perceived trust, considering the evolving nature of EEW technologies and users’ familiarity over time. The descriptive and inferential analysis results raised concerns about potential confusion around the alerts’ source and highlighted the question of responsibility and liability for EEW. Overall, this study contributes to understanding continuance intention in the EEW context and provides insights into the public’s perception of the AEA system in New Zealand. The findings have implications more broadly for EEW systems’ design, implementation, and communication strategies

The peritonsillar abscess and its management – is incision and drainage only a makeshift to the tonsillectomy or a permanent solution?

IntroductionThis study aims to examine the long-term management of peritonsillar abscess and compare needle aspiration, incision with drainage, and tonsillectomy in terms of comorbidities, complication rates, and recurrences in the largest study cohort published to date.MethodsWe conducted a retrospective analysis of patients, both adults and children, who were treated for peritonsillar abscess between 2007 and 2019. Patient charts were analyzed to assess surgical treatment, infection and inflammation rates, risk of bleeding, recurrence rates, duration of illness, and sick certificates. Additionally, patient imaging and blood levels were compared. Postal questionnaires were sent to all patients to evaluate subjective success rates, complications, and long-term benefits of the different treatment regimens. General practitioners and ENT doctors in private practices were contacted to gather missing data on the long-term course of the disease.ResultsA total of 821 patients with peritonsillar abscess were included in this study. Two patients had to be excluded due to incidental pathological findings. Of the remaining 819 patients, 180 were successfully treated with needle aspiration or incision. Among these patients, 37.7% required tonsillectomy during the same inpatient stay. Laboratory parameters such as leukocyte count or C-reactive protein levels were not indicative of the need for tonsillectomy. Furthermore, computed tomography was only necessary in cases of suspected parapharyngeal abscess, not in clear cases of peritonsillar abscess. Among the 641 patients who underwent tonsillectomy, 11.4% experienced postoperative bleeding requiring treatment. Only patients who underwent bilateral tonsillectomy reported recurrent episodes of sore throat and pharyngitis resulting in absence from work. The ipsilateral recurrence rate for peritonsillar abscess after needle aspiration or incision was 2.8%. There were no contralateral recurrences during the observation period.ConclusionDue to the lower risk of postoperative bleeding, shorter absence from work, and shorter inpatient stay, incision and drainage are the preferable treatment for peritonsillar abscess. Additionally, patients who underwent bilateral tonsillectomy reported higher rates of work incapacity due to sore throat caused by pharyngitis. No patient met the clear indication for bilateral tonsillectomy due to recurrent acute tonsillitis. The recurrence rate after drainage without tonsillectomy was very low (2.8% ipsilaterally, no recurrence contralaterally)

Modified spin-wave theory with ordering vector optimization I: frustrated bosons on the spatially anisotropic triangular lattice

We investigate a system of frustrated hardcore bosons, modeled by an XY antiferromagnet on the spatially anisotropic triangular lattice, using Takahashi's modified spin-wave (MSW) theory. In particular we implement ordering vector optimization on the ordered reference state of MSW theory, which leads to significant improvement of the theory and accounts for quantum corrections to the classically ordered state. The MSW results at zero temperature compare favorably to exact diagonalization (ED) and projected entangled-pair state (PEPS) calculations. The resulting zero-temperature phase diagram includes a 1D quasi-ordered phase, a 2D Neel ordered phase, and a 2D spiraling ordered phase. We have strong indications that the various ordered or quasi-ordered phases are separated by spin-liquid phases with short-range correlations, in analogy to what has been predicted for the Heisenberg model on the same lattice. Within MSW theory we also explore the finite-temperature phase diagram. We find that the zero-temperature long-range-ordered phases turn into quasi-ordered phases (up to a Berezinskii-Kosterlitz-Thouless temperature), while zero-temperature quasi-ordered phases become short-range correlated at finite temperature. These results show that modified spin-wave theory is very well suited for describing ordered and quasi-ordered phases of frustrated XY spins (or, equivalently, of frustrated lattice bosons) both at zero and finite temperatures. While MSW theory, just as other theoretical methods, cannot describe spin-liquid phases, its breakdown provides a fast method for singling out Hamiltonians which may feature these intriguing quantum phases. We thus suggest a tool for guiding our search for interesting systems whose properties are necessarily studied with a physical quantum simulator.Comment: 40 pages, 16 figure