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Ein 64-jahriger Mann stellte sich mit einer Sepsis auf der Notfallstation vor. In der Blutentnahme zeigten sich als Nebenbefund ein TSH von 0,03 mU/l, ein fT3 von

ObjectiveThis paper define a method for optimizing the breath delineation algorithms used in Electrical Impedance Tomography (EIT). In lung EIT the identification of the breath phases is central for generating tidal impedance variation images, subsequent data analysis and clinical evaluation. The optimisation of these algorithms is particularly important in neonatal care since the existing breath detectors developed for adults may give insufficient reliability in neonates due to their very irregular breathing pattern.ApproachOur approach is generic in the sense that it relies on the definition of a gold standard and the associated definition of detector sensitivity and specificity, an optimisation criterion and a set of detector parameters to be investigated. The gold standard has been defined by 11 clinicians with previous experience with EIT and the performance of our approach is described and validated using a neonatal EIT dataset acquired within the EU-funded CRADL project.Main resultsThree different algorithms are proposed that are improving the breath detector performance by adding conditions on 1) maximum tidal breath rate obtained from zero-crossings of the EIT breathing signal, 2) minimum tidal impedance amplitude and 3) minimum tidal breath rate obtained from Time-Frequency (TF) analysis.SignificanceBased on the gold standard, the most crucial parameters of the proposed algorithms are optimised by using a simple exhaustive search and a weighted metric defined in connection with the Receiver Operating Characterics (ROC). This provides a practical way to achieve any desirable trade-off between the sensitivity and the specificity of the detectors.

Classical homogenization theory based on the Hashin-Shtrikman coated ellipsoids is used to model the changes in the complex valued conductivity (or admittivity) of a lung during tidal breathing. Here, the lung is modeled as a two-phase composite material where the alveolar air-filling corresponds to the inclusion phase. The theory predicts a linear relationship between the real and the imaginary parts of the change in the complex valued conductivity of a lung during tidal breathing, and where the loss cotangent of the change is approximately the same as of the effective background conductivity and hence easy to estimate. The theory is illustrated with numerical examples, as well as by using reconstructed Electrical Impedance Tomography (EIT) images based on clinical data from an ongoing study within the EU-funded CRADL project. The theory may be potentially useful for improving the imaging algorithms and clinical evaluations in connection with lung EIT for respiratory management and monitoring in neonatal intensive care units.

The objective of this paper is to report our investigation demonstrating that the phase angle information of complex impedance could be a simple indicator of a breath cycle in chest Electrical Impedance Tomography (EIT). The study used clinical neonatal EIT data. The results show that measurement of the phase angle from complex EIT data can be used as a complementary information for improving the conventional breath detection algorithms.

Spectral analysis based on short-time Fourier transform (STFT) using Kaiser window is proposed to examine the frequency components of neonates EIT data. In this way, a simultaneous spatial-time-frequency analysis is achieved.

Der Start zur Reorganisation des Interdisziplinaren Notfallzentrums am Kantonsspital Aarau erfolgte im Jahre 2010, da es zwischen 2005 und 2010 einen Zuwachs an Notfallpatienten von 30% verzeichnete.

The radical cations of dicyclopropylidenemethane (2) and its octamethyl derivative (2-Me8) are prone to rearrangements into those of (2-methylallylidene)cyclopropane (2a) and its octamethyl derivative (2a-Me8), respectively, by opening one three-membered ring. In contrast to the radical cations of bicyclopropylidene (1) and its octamethyl derivative (1-Me8), 2*+ and 2-Me8*+ are stable to opening of the second ring, because in this case the resulting species would be a non-Kekulé hydrocarbon with a quartet ground state. Similarly to 1, octamethyl substitution in 2 promotes the tendency to rearrangement. Thus, ESR and ENDOR studies indicate that the primary radical cation 2*+, which is formed upon gamma-irradiation of 2 in a CFCl3 matrix at 77 K, does not rearrange up to 150 K. On the other hand, when 2-Me8 is treated in the same way, only the rearranged radical cation 2a-Me8*+ can be observed and characterized by its ESR and ENDOR spectra. Nevertheless, the existence of the two "missing" species, 2a*+ and 2-Me8*+, is revealed by other methods. According to UV and IR studies, X irradiation of 2 in an Ar matrix leads directly to the ring-opened radical cation 2a*+. Moreover, magnetic field effects on the decay of fluorescence, which appears upon recombination of the radical anion of p-terphenyl with a radical cation generated from 2-Me8 in liquid octane, strongly suggest that 2-Me8*+ (and not 2a-Me8*+) is formed initially. From the temperature dependence of the decay, the activation energy of the ring-opening process 2-Me8*+ --2a-Me8*+ is estimated. The radical cations 2a*+ and 2a-Me8*+ are formally distonic with the spin residing in the allylic moiety and the charge accommodated on the central carbon atom of the allene pi-system. The intact cyclopropylidenemethylidene moiety assumes a "bisected" conformation, thus favoring an optimal interaction with the positively charged center on the pi-system.

The OH group of the iminol complex [IrH2L′(PPh3)2]SbF6·2H2O where L′ is the iminol tautomer of quinolin-8-acetamide, takes part in an O–H ⋯ H–Ir hydrogen bond.

A Simple Route to 3-Amino-nocardicinic Acid Starting from nocardicin A (1), a novel and efficient procedure for the preparation of 3-amino-nocardicinic acid (4) and its protected derivatives 6 and 8–11 is described.

Neue Cephalosporine, die in 3-Stellung eine Fluormethylgruppe aufweisen (9, 17/Schema 1), wurden ausgehend von 2b unter Verwendung von 2-Chlor-1,1,2-trifluor-triathylamin als Fluorierungsmittel hergestellt. Mit Piperidin-schwefeltrifluorid erhielt man ferner aus 18 die 3-Difluormethyl-cephemverbindung 19 (Schema 2), die nach bekannten Methoden in antibakteriell wirksame Cephalosporine (20a, b) ubergefuhrt wurde. 3-Fluor-cephemderivate, z.B. 23b, liessen sich ausgehend von entsprechenden 3-Hydroxy-cephemverbindungen, mit diesem Reagens jedoch nur in sehr geringer Ausbeute herstellen.

New β-lactam antibiotics. Cephem derivatives with electron withdrawing substituents at position 3 Oxidation of the 3-formyl-2-cephem compound 1 according to Corey [6] gave 2-cephem-3-carboxylic esters 4a, b, c (Scheme 1), which proved to be useful intermediates for the synthesis of cephalosporins bearing in position 3 a methoxycarbonyl group (10a, b, c, d / Scheme 2) or a carboxy group (20, 25, 30/Schemes 3, 4). The 3-formyl-3-cephem compounds 31a, b could be transformed into cyano- (33a) or methoxyiminomethyl- (36a, c, d) cephems (Scheme 5), which represent further examples of cephalosporins with electron withdrawing groups in position 3.

7-Phenylacetamido-3-trifluoroacetoxymethyl-ceph-2-em-4-carboxlic acid (7), which is easily produced from the iso-cephalosporanic acid derivatives 4 or 6 by treatment with trifluoroacetic acid, reacts smoothly with ‘C-nucleophiles’ to give derivatives of type 5 (Schema 1 and 2). Compounds 5 are converted into microbiologically active cephalosporins of type 8 (Table) by previously described methods.

A new method for the preparation of 2,3,1-diazaborines is described. It is suggested that the observed formation of the C,B-bond by electrophilic attack with a boron halide is facilitated and o-directed by the sulfonyl hydrazone group of the educts.