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A problem which frequently arises in wireless network and radar engineering is the calculation of propagation losses through the troposphere. While a wealth of literature and software exists for propagation geometries characteristic of terrestrial satellite and point to point links, and surface based radar installations, the more general case is less frequently addressed. This paper discusses the design and implementation of the TROPospheric PrOpagation (TROPPO) simulator tool, which implements a general propagation model for pairs of stations with arbitrary altitudes up to the lower stratosphere. TROPPO solves the nonlinear refractive ODE boundary value problem, and implements models for water vapour and oxygen resonances, cloud droplet scattering, rain absorption and lense effect loss, for a wide range of configurable initial conditions. The Friis pathlength loss is modelled and receiver SNR and link Shannon capacity are calculated. The report presents calibration curves for most of the models, and examples of link parameter calculations.

Jahreshefte des Vereins für Vaterländische Naturkunde in Württemberg : zugl. Jahrbuch d. Staatlichen Museums für Naturkunde in Stuttgart, Bd. 60, 1904

During their early life stage as planktonic larvae, reef-building corals do not rely on their photosynthesizing symbionts for nutrition., Dispersion of larval offspring is of fundamental ecological importance to sessile marine organisms. Photosymbiotic planulae emitted by many reef-forming corals may travel over large distances before settling to form a new colony. It is not clear whether the metabolic requirements of these planula larvae are met exclusively with lipid and protein reservoirs inherited from the mother colony or when metabolic inputs from their endosymbiotic dinoflagellates become important. Pulse-chase experiments using [13C]bicarbonate and [15N]nitrate, combined with subcellular structural and isotopic imaging of freshly emitted symbiotic larvae from the coral Pocillopora damicornis, show that metabolic input from the dinoflagellates is minimal in the planulae compared with adult colonies. The larvae are essentially lecithotrophic upon emission, indicating that a marked shift in metabolic interaction between the symbiotic partners takes place later during ontogeny. Understanding the cellular processes that trigger and control this metabolic shift, and how climate change might influence it, is a key challenge in coral biology.

International audience; Somatostatin (SRIF) controls many physiological and pathological processes in the central nervous system but the respective roles of the five receptor isotypes (sst1-5) that mediate its effects are yet to be defined. In the present study, we attempted to identify functions of the sst2 receptor using mice with no functional copy of this gene (sst2 KO mice). In contrast with control 129Sv/C57Bl6 mice, sst2 mRNA was no longer detectable in the brain of sst2 KO mice; 125I-labeled Tyr0DTrp8-SRIF14 binding was also greatly reduced in almost all brain structures except for the hippocampal CA1 area, demonstrating that sst2 accounts for most SRIF binding in mouse brain. Invalidation of this subtype generated an increased anxiety-related behaviour in a number of behavioural paradigms, while locomotor and exploratory activity was decreased in stress-inducing situations. No major motor defects could be detected. sst2 KO mice also displayed increased release of pituitary ACTH, a main regulator of the stress response. Thus, somatostatin, via sst2 receptor isotype pathways, appears involved in the modulation of locomotor, exploratory and emotional reactivity in mice.

Myelodysplastic syndromes (MDS) may be accompanied by systemic mastocytosis. The mechanisms which play a role in the evolution of mastocytosis, however, are not well understood. We report on a case of refractory and anemia with ringed sideroblasts (RARS), and co-existing bone marrow mastocytosis. Compact mast cell (MC) infiltrates were detected in bone marrow sections by immunohistochemistry using an antibody to tryptase. In addition, the MC were found to express c-kit, the tyrosine kinase receptor for MGF (mast cell growth factor = stem cell factor, SCF). Activating point mutations in the kinase domain of c-kit (often found in mastocytosis) were not detectable. However, the mononuclear cells (MNC) of the bone marrow expressed mRNA specific for MITF, a transcription factor that regulates expression of c-kit and differentiation of MC. Surprisingly, the c-kit ligand SCF was found to augment expression of MITF mRNA in bone marrow MNC. Whether this augmentation represents a general response (preventing loss of growth factor receptor expression during cell maturation) common to all types of hemopoietic progenitors, or is confined to (some forms of) mastocytosis, remains unknown.

The aim of the study was to examine the determinants of blood antioxidant indicators on a large sample. Levels of plasma selenium and carotenoids, vitamin E in red blood cells, and thiobarbituric acid reactive substances (TBARS) were determined. The cross-sectional relationships between these markers and demographic and cardiovascular risk factors were examined in participants of the EVA study, a cohort of 1389 men and women, aged 59-71 years. Multivariable regression models including demographic (age, sex, socio-economic level), lifestyle (alcohol, tobacco), clinical and metabolic (lipids, glycemia) factors were used. Women had higher levels of plasma carotenoids, TBARS and red blood cell vitamin E. Cholesterol levels were positively associated to lipid-soluble vitamins, selenium and TBARS. Use of lipid-lowering drugs was positively associated with selenium and vitamin E and negatively with carotenoids. Body mass index was the strongest determinant of plasma carotenoids. Education and income levels were positively associated with selenium and total carotenoids. Tobacco consumption was negatively associated with red blood cell vitamin E, whereas alcohol consumption was positively associated with TBARS. This study emphasizes the respective place of the various determinants of antioxidant status. When considering tissue antioxidant indicators, analyses should take into account not only the metabolic parameters but also socio-economic factors and the subject's life style.

In patients with suspected sarcoidosis histological confirmation is generally desired. In 40 patients with the ultimate diagnosis of sarcoidosis transbronchial lung biopsy during fiberoptic bronchoscopy revealed in 83% noncaseating granulomas. With 5 biopsies per patient a positive result was obtained in 20 of 25 patients (80%) with radiographic stage I disease, in 6 of 7 (85%) with stage II disease and in 7 of 8 (87%) with stage III disease. The only complications were two small pneumothoraces and two hemorrhages. Transbronchial biopsy with its low morbidity and high diagnostic yield can be recommended as an initial procedure in diagnosing sarcoidosis.

Einleitend wird die Pathogenese des Cor pulmonale und die daraus abzuleitenden prophylaktisch-therapeutischen Moglichkeiten dargestellt. Aufgrund eigener Untersuchungen wird sodann die Verminderung der pulmonalen arteriellen Hypertension durch die Behandlung der Krankheiten der Atmungsorgane und durch die Bekampfung der daraus resultierenden respiratorischen Insuffizienz diskutiert. Die gegenseitigen Beziehungen zwischen Pulmonalisdruck, arterieller Sauerstoffspannung, relativer Sekundenkapazitat und Vitalkapazitat werden analysiert. Bei obstruktiven Syndromen wird der Pulmonalisdruck pathologisch hoch, wenn die relative Sekundenkapazitat unter 40% sinkt, bei restriktiven Syndromen dagegen, wenn die Vitalkapazitat unterhalb 70% des Sollwertes fallt. Bei 27 Patienten mit obstruktiver Lungenkrankheit wird anschliesend die Wirkung einer zweijahrigen Arosoltherapie mit intermittierender Uberdruckbeatmung im Anschlus an eine zweijahrige Kontrollperiode demonstriert: die Vitalkapazitat und die Sekundenkapazitat nehmen dauerhaft zu, die progrediente Zunahme der totalen Lungenkapazitat und die Verschlechterung der arteriellen Blutgase werden aufgehalten. Bei einmal etabliertem Cor pulmonale fuhren Hyperoxie und intermittierende Uberdruckbeatmung, besonders aber die Kombination von beiden immer zu einer wirksamen Herabsetzung des Pulmonalisdruckes. Abschliesend wird die Notwendigkeit der Vermeidung von korperlichen Anstrengungen bei ausgebildetem Cor pulmonale begrundet: wahrend beim Gesunden bei Verdoppelung des Herzminutenvolumens unter Belastung der Pulmonalisdruck bestenfalls um 20% steigt, kommt es beim Patienten mit Cor pulmonale unter denselben Bedingungen zu einer Erhohung des Pulmonalisdruckes auf das Dreifache des Ausgangswertes.

In clinical practice, a wide variety of drugs are given to modify the rheological properties of bronchial mucus but they are frequently not correctly chosen because there is not a simple apparatus available for the routine measurement of the mucus viscoelasticity. We designed a new viscoelastometer which is easy to operate and permit accurate measurement of the viscoelastic properties of mucus. The system has a Couette geometry and requires a sample of 1 ml. The outer cylinder is thermostated and rotates at a constant rate. The resulting torque is measured on the inner cylinder using a microdisplacement transducer. The inner cylinder is suspended by a special wire system which maintains a constant 0.75 mm gap between the two cylinders. The apparent viscosity is calculated up to 100 Pa.s. at a low shear rate (0.4 s-1) and the elasticity is analyzed by a stress relaxation method. The characteristics of the apparatus and the typical viscoelasticity behaviour of several sputum samples are reported.

Assimilation of inorganic nitrogen from nutrient-poor tropical seas is an essential challenge for the endosymbiosis between reef-building corals and dinoflagellates. Despite the clear evidence that reef-building corals can use ammonium as inorganic nitrogen source, the dynamics and precise roles of host and symbionts in this fundamental process remain unclear. Here, we combine high spatial resolution ion microprobe imaging (NanoSIMS) and pulse-chase isotopic labeling in order to track the dynamics of ammonium incorporation within the intact symbiosis between the reef-building coral Acropora aspera and its dinoflagellate symbionts. We demonstrate that both dinoflagellate and animal cells have the capacity to rapidly fix nitrogen from seawater enriched in ammonium (in less than one hour). Further, by establishing the relative strengths of the capability to assimilate nitrogen for each cell compartment, we infer that dinoflagellate symbionts can fix 14 to 23 times more nitrogen than their coral host cells in response to a sudden pulse of ammonium-enriched seawater. Given the importance of nitrogen in cell maintenance, growth and functioning, the capability to fix ammonium from seawater into the symbiotic system may be a key component of coral nutrition. Interestingly, this metabolic response appears to be triggered rapidly by episodic nitrogen availability. The methods and results presented in this study open up for the exploration of dynamics and spatial patterns associated with metabolic activities and nutritional interactions in a multitude of organisms that live in symbiotic relationships. © 2012 International Society for Microbial Ecology All rights reserved.