Differenzialdiagnose Nausea und Erbrechen

Zusammenfassung: Nausea und Erbrechen sind häufig. Sie können eine physiologische Antwort auf ein exogenes Toxin sein, aber auch Ausdruck einer organischen, psychischen oder funktionellen Erkrankung. Trotz der Fülle der Differenzialdiagnose gelingt es meist durch sorgfältige Anamnese und wenige Untersuchungen, den Auslöser zu finden. Die Ursachen akuter Beschwerden unterscheiden sich teilweise von denen chronischer. Bei Frauen im gebärfähigen Alter ist eine Schwangerschaft auszuschließen. Eine symptomatische Therapie kann bereits zu Beginn eingeleitet werden. Die Klärung chronischer Ursachen ist schwieriger. Funktionstests wie die Messung der Magenentleerung ergänzen die Diagnostik. Sie sollen nur in spezialisierten Zentren mit entsprechender Erfahrung durchgeführt werden. Ruminieren und Regurgitation sind von Erbrechen abzugrenzen. Findet sich keine Ursache für die Beschwerden, kann von einer funktionellen Erkrankung ausgegangen werde

On the origin of X-ray spectra in luminous blazars

Gamma-ray luminosities of some quasar-associated blazars imply jet powers reaching values comparable to the accretion power even if assuming very strong Doppler boosting and very high efficiency of gamma-ray production. With much lower radiative efficiencies of protons than of electrons, and the recent reports of very strong coupling of electrons with shock-heated protons indicated by Particle-in-Cell (PIC) simulations, the leptonic models seem to be strongly favored over the hadronic ones. However, the electron-proton coupling combined with the ERC (External-Radiation-Compton) models of gamma-ray production in leptonic models predict extremely hard X-ray spectra, with energy indices about 0. This is inconsistent with the observed 2-10 keV slopes of blazars, which cluster around an index value of 0.6. This problem can be resolved by assuming that electrons can be cooled down radiatively to non-relativistic energies, or that blazar spectra are entirely dominated by the SSC (Synchrotron-Self Compton) component up to at least 10 keV. Here, we show that the required cooling can be sufficiently efficient only at distances r < 0.03pc. SSC spectra, on the other hand, can be produced roughly co-spatially with the observed synchrotron and ERC components, which are most likely located roughly at a parsec scale. We show that the dominant SSC component can also be produced much further than the dominant synchrotron and ERC components, at distances larger than 10 parsecs. Hence, depending on the spatial distribution of the energy dissipation along the jet, one may expect to see gamma-ray/optical events with either correlated or uncorrelated X-rays. In all cases the number of electron-positron pairs per proton is predicted to be very low. The direct verification of the proposed SSC scenario requires sensitive observations in the hard X-ray band which is now possible with the NuSTAR satellite.Comment: 19 pages, 1 figure, accepted for publication in Ap

Novel structural features of the ripple phase of phospholipids

We have calculated the electron density maps of the ripple phase of dimyristoylphosphatidylcholine (DMPC) and palmitoyl-oleoyl phosphatidylcholine (POPC) multibilayers at different temperatures and fixed relative humidity. Our analysis establishes, for the first time, the existence of an average tilt of the hydrocarbon chains of the lipid molecules along the direction of the ripple wave vector, which we believe is responsible for the occurrence of asymmetric ripples in these systems

Emerging trends for urban freight transport-The potential for sustainable micromobility

Aim Active transportation referring to non-motorized modes of transport is promoted and popularized both in practice and in the scientific literature, while their use for urban freight transport has been largely neglected. Thus the main scope of the paper is to indicate the development potential of micromobility use in urban freight transport and to check its influence on urban sustainability. Methods The authors have hypothesized that active means of transport, with a focus on micromobility, have great development potential in freight transportation in cities. The implemented methods for analyzing the relationship between users’ characteristics, micromobility, and its impact on urban sustainable development, were logit and probit modelling. The authors’ system includes an analysis of factors connected with the topics of sustainability and micromobilty, that have met an essential scientific gap that this paper addresses. Logistic (logit) regression is used mainly for binary, ordinal, and multi-level outcomes to find the probability of success (i.e. occurrence of some event). Probit regression, however, is primarily used in binary response models and assumes the normal distribution of data. Results The main finding of the article has led the authors to the statement that active means of transport, including micromobility have great development potential in freight transportation in cities. Conclusions Knowledge of the acceptance of micromobility solutions is essential for municipal authorities in shaping the development of urban transport systems. Thus proper strategies and actions need to be prioritized to leverage the sustainability-related co-benefits of active transport

Preparation of metallic target of 100Mo for production of 99mTc in cyclotron

Introduction Technetium-99m, the daughter of 99Mo is the most commonly used radioisotope in nuclear medicine [1–2]. Current global crisis of 99Mo supply, aging of nuclear reactors and staggering costs force the search for alternative sources of 99mTc. Radioisotope Centre POLATOM joined the IAEA Coordinated Research Project on “Accelerator-based Alternatives to Non-HEU Production of 99Mo/99mTc”. The planned outcome of this project is development of 99mTc production method using the reaction of 100Mo(p,2n)99mTc [3] in Polish cyclotron. This work presents the results concerning preparation of 100Mo target for irradiation with protons. Material and Methods The manufacturing of Mo target was performed using pressing of molybdenum powder into pellets and its sintering in hydrogen atmosphere at 1600 oC [4]. For this purpose a tantalum and stainless steel plates were used as support. Several pellets using molybdenum powder with particles size of 2 µm in diameter were pressed at different values of pressure. Results and Conclusion The optimized parameters of pressing molyb-denum pellets with various sizes are given in TABLE 1. It was found that the pellets did not adhere neither to the tantalum nor stainless steel plates but they conducted electricity very well. Pellets prepared with higher pressure were more mechanically resistant, however application, even the highest used pressure did not ensure its satisfactory stability. In order to improve mechanical strength, pressed Mo pellets were sintered in hydrogen atmosphere at temperature of 1600 °C. As a result of this process dimensions of Mo pellets decreased: diameter by 13 %, thickness by 12 %, weight by 1.5 %, volume by 34 % while density increased by 50 %. The changes of these parameters are associated with reduction of molybdenum oxide and removal of oxygen from intermetallic space. It was confirmed by photos of microscopic cross section of pellets before and after sintering. It was observed, that after sintering Mo pellets got a metallic form with very high hardness and mechanical strength

Evidence of environmental strains on charge injection in silole based organic light emitting diodes

Using d. functional theory (DFT) computations, the authors demonstrated a substantial skeletal relaxation when the structure of 2,5-bis-[4-anthracene-9-yl-phenyl]-1,1-dimethyl-3,4-diphenyl-silole (BAS) is optimized in the gas-phase comparing with the mol. structure detd. from monocrystal x-ray diffraction. The origin of such a relaxation is explained by a strong environmental strains induced by the presence of anthracene entities. Also, the estn. of the frontier orbital levels showed that this structural relaxation affects mainly the LUMO that is lowered of 190 meV in the gas phase. To check if these theor. findings would be confirmed for thin films of BAS, the authors turned to UV photoemission spectroscopy and/or inverse photoemission spectroscopy and electrooptical measurements. The study of the c.d. or voltage and luminance or voltage characteristics of an ITO/PEDOT/BAS/Au device clearly demonstrated a very unusual temp.-dependent behavior. Using a thermally assisted tunnel transfer model, this behavior likely originated from the variation of the electronic affinity of the silole deriv. with the temp. The thermal agitation relaxes the mol. strains in thin films as it is shown when passing from the cryst. to the gas phase. The relaxation of the intramol. thus induces an increase of the electronic affinity and, as a consequence, the more efficient electron injection in org. light-emitting diodes

EFFECT OF LOW DOSES OF LOW-LET RADIATION ON THE INNATE ANTITUMOR REACTIONS IN RADIORESISTANT AND RADIOSENSITIVE MICE

BALB/c and C57BL/6 mice differ in their Th1/Th2 lymphocyte and M1/M2 macrophage phenotypes, radiosensitivity, and post-irradiation tumor incidence. In this study we evaluated the effects of repeated low-level exposures to X-rays on the development of artificial tumor colonies in the lungs of animals from the two strains and cytotoxic activities of natural killer (NK) cells and macrophages obtained from these mice. After ten daily irradiations of BALB/c or C57BL/6 mice with 0.01, 0.02, and 0.1 Gy X-rays NK cell-enriched splenocytes collected from the animals demonstrated significant and comparable up-regulation of their anti-tumor cytotoxic function. Likewise, peritoneal macrophages collected from the two irradiated strains of mice exhibited the similarly stimulated cytotoxicities against susceptible tumor cells and produced significantly more nitric oxide. These results were accompanied by the significantly reduced numbers of the neoplastic colonies induced in the lungs by intravenous injection of syngeneic tumor cells. The obtained results indicate that ten low-level irradiations with X-rays stimulate the generally similar anti-tumor reactions in BALB/c and C57BL/6 mice

Synthesis and structural characterization of Cd(II) complexes with 2-acetylpyridine-aminoguanidine - a novel coordination mode

The structures of the first two complexes with bidentate coordination of aminoguanidine Schiff base, i.e., 2-acetylpyridine-aminoguanidine (L), are reported. The complex of the formula [Cd2Cl6(HL)2] (1) was obtained in the reaction of warm aqueous solutions of chloride salts of Cd(II), Zn(II) and the ligand, while the reaction of cadmium bromide and the ligand in the presence of deprotonating agent as well as ammonium thiocyanate resulted in the formation of the complex in which Schiff base has both the role of the ligand and the counterion, viz., [HL][Cd(HL)(NCS)2XY]·H2O (2), where X is Cl- or Br-, and Y Br- or SCN-. The complexes were characterized by IR spectroscopy, elemental analysis, conductometric measurements and single crystal X-ray diffraction. The unusual bidentate coordination of the Schiff base lead to significant changes in the geometry of this molecule (from almost planar in free form and as a tridentate ligand to twisted as a bidentate ligand). Besides, in complex 1 relatively rare bridging coordination of Cl- in octahedral Cd(II) is found, while the crystal structure of complex 2 exhibits substitutional disorder, and contains four different anions: [Cd(HL)(NCS)2Br(SCN)]- (ca. 61 %), [Cd(HL)(NCS)2Cl(SCN)]- (ca. 35 %), [Cd(HL)(NCS)2Br2]- (ca. 3 %) and [Cd(HL)(NCS)2ClBr]- (ca. 1 %)