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Distributed phased array radar networks provide an improved target detection and parameter estimation performance due to extended spatial coverage and multiple observation perspectives. By increasing a network’s baseline, these capabilities can be further enhanced. However, the spatial area that the Rx stations need to cover increases with growing baselines, requiring a high number of Rx beams. This poses a challenge, since the number of receiving channels is often limited by hardware or software. Therefore, designing the Rx beamformer is a key factor for baseline extension and network performance. In this paper, we analyze the use of two different beamformers for a bistatic network configuration: a commonly used sum beam method and a recently proposed eigenbeamformer. The numerical results demonstrate the superiority of the eigenbeamformer in parameter estimation accuracy, resource efficiency and baseline extension ability.

The daily life on earth relies on the undisturbed services of satellites and space missions. With the growing amount of space debris particles the space-based infrastructure is increasingly endangered. To protect satellites and space missions it is mandatory to identify, track and monitor space debris objects with highly sensitive radar sensors. To support the German Space Situational Awareness Center, the Fraunhofer Institute for High Frequency Physics and Radar Techniques (FHR) was commissioned by the DLR Space Administration in 2015 to design a high performance L-band phased-array radar to observe the low-earth orbit: GESTRA (German Experimental Space Surveillance and Tracking Radar). The long-term aim of GESTRA is to build up a catalog with orbital data for objects located at altitudes of less than 3000 km. GESTRA will provide valuable data sets for the global space situational awareness efforts.

Distributed radar systems are attractive for space surveillance because they enable an improvement in network performance through improved coverage and multiple observation perspectives. This paper presents a performance evaluation of a number of practical distributed radar aspects for a space surveillance application. A concept of pulse chasing for a bistatic configuration with long baseline is presented and the requirement on the number of simultaneous receive beams is analyzed. Additionally, the influence of synchronization errors on the overall measurement accuracy is investigated and examples of the detectability gain through multiple signal paths is presented. These results confirm the feasibility of distributed radar concept for space surveillance. 1

Previous studies on various vertebrates have shown that quantity and quality of food intake affect odour attractiveness as perceived by potential mates. In humans, the quality of body odour is similarly affected by ingested foods, such as by variation in meat and garlic intake. Nevertheless, it is not known whether quantity of food has an impact on human body odour attractiveness. Thus, here we tested how 48 h of complete caloric intake restriction affects the hedonic quality of human axillary odour. Odour samples (cotton pads fixed in both armpits and worn for 12 h) were obtained from healthy female donors across three conditions: i) during their habitual food regime; ii) after 48 h of complete caloric intake restriction (drinking water was provided), and iii) 72 h after restoration of caloric intake. Axillary samples were assessed by male raters regarding their pleasantness, attractiveness, femininity, and intensity. We also collected blood samples to assess physiological changes due to dietary restriction (e.g., glucose, sodium, albumin, and triacylglyceride assays) and anthropometric measurements at the same intervals as body odour samples. We found no differences in pleasantness, attractiveness and intensity between the odour samples collected at baseline and during complete caloric intake restriction. Interestingly, we found that body odours were rated more pleasant, more attractive and less intense after restoration of food intake as compared to the baseline and during caloric restriction. Our results suggest that restoration of food intake positively influences hedonic quality of human body odour which might thus provide cues to current fitness status and metabolic efficiency.

The aim of the study was to characterize the value of combined endoscopy of tracheobronchial tree and oesophagus within 1 session for diagnosis of HIV-associated disorders. Hospitalized HIV-positive patients who underwent combined flexible broncho-oesophagoscopies between 1999 and 2002 in 2 units for infectious diseases were studied retrospectively. 54 HIV patients were analysed; 89% were at stage CDC C, 79% were male, mean age was 40 y. Bronchoscopy led to a diagnosis in 57.4% (95% CI 43.2-70.8). In 40.7%, these were AIDS-defining events (ADE) and 16.7% were general disorders (GD). Oesophagoscopy was diagnostic in 46.3% (95% CI 32.6-60.4). In 35.2% these were ADE, and 11.1% were GD. Patients with pathological oesophagoscopy had a significantly lower CD4 cell count and a higher viral load. There was no association of pathological bronchoscopy with pathological oesophagoscopy regarding ADE. No severe complication was recorded. It is concluded that combined flexible broncho-oesophagoscopy is a valuable and safe method for the diagnosis of HIV-associated disorders. The diagnostic output is highest in patients with advanced disease. A pathological finding in oesophagoscopy cannot be predicted by the presence of bronchoscopic abnormalities. Prospective studies are necessary to confirm these results.

Rhesus-positive and Rhesus-negative persons differ in the presence-absence of highly immunogenic RhD protein on the erythrocyte membrane. The biological function of the RhD molecule is unknown. Its structure suggests that the molecular complex with RhD protein transports NH3 or CO2 molecules across the erythrocyte cell membrane. Some data indicate that RhD positive and RhD negative subjects differ in their tolerance to certain biological factors, including, Toxoplasma infection, aging and fatique. Present cross sectional study performed on 3,130 subjects) showed that Rhesus negative subjects differed in many indices of their health status, including incidences of many disorders. Rhesus negative subjects reported to have more frequent allergic, digestive, heart, hematological, immunity, mental health, and neurological problems. On the population level, a Rhesus-negativity-associated burden could be compensated for, for example, by the heterozygote advantage, but for Rhesus negative subjects this burden represents a serious problem.

Well-characterized Group 14 Zintl anions were accessible by solution methods only in low yields up to now. An easy and inexpensive reaction route to polyanions, which starts from the elements, is admissible through the usage of [18]crown-6 as reaction medium at 40°C. The [K([18]crown-6)] unit proves to be an advantageous connecting device between intermetallic and organic networks. The title compound can be regarded as a supramolecular aggregate of a one-dimensional substructure of the composition K4Sn9 (see picture) and an organic component.

Our objective was to evaluate diagnostic tools for the detection of Inclusion Body Disease (IBD) in bold snakes. The aetiology of IBD is unknown, and the disease has non-specific clinical signs, hence there is a need for a clinically-applicable, specific diagnostic method. We examined blood smears and liver biopsies from 26 bold snakes (17 boas and nine pythons; some of which were suspected of having IBD) for the presence of characteristic inclusion bodies. We used haematology, histology and electron microscopy to characterise samples as IBD-positive or -negative. Our results indicate that examination of a simple blood smear is sufficient to diagnose IBD in boas. Inclusion bodies in lymphocytes, erythrocytes and thrombocytes were observed. In both, boas and pythons, we detected inclusion bodies within hepatocytes. We demonstrated also that IBD was more common in boas than in pythons: only samples from two Ball Pythons (Python regius) tested positive, whereas no other Pythonidae were positive. We consider that blood smears represents a rapid, non-invasive technique for detection of IBD.

Hierarchically structured zinc oxide was prepared from zinc acetylacetonate by a microwave-assisted process. The zinc oxide formed nanoparticles that are packed in substructured spherical agglomerates with a diameter of 0.5 μm. Nitrogen adsorption, x-ray diffraction, and dilatometry were used to investigate the densification. Ion beam method was applied to prepare cross sections and enable microstructural analysis. Three regimes of microstructural evolution were identified on different scales during sintering. In the first regime, nanoparticles changed morphology and densification occurred only in the interiors of the agglomerates. In the second regime, agglomerates became hollow and built necks. Simultaneously, densification set in on the macroscopic scale. A drastic homogenization of the microstructure was observed that marked the beginning of the third regime, where densification and grain growth occurred.

Background The aim of this article is to make physicians of all specialties aware of the possible variations of clinical course in human cowpox infection. This has been a matter of current interest since the detection of a first cluster of infections among owners of white pet rats in the Krefeld area in the spring of 2008. Two further cases arose in the Krefeld area in November 2008, and there have since been multiple further reports from various regions in Germany and the neighboring countries.

The aim of this article is to make physicians of all specialties aware of the possible variations of clinical course in human cowpox infection. This has been a matter of current interest since the detection of a first cluster of infections among owners of white pet rats in the Krefeld area in the spring of 2008. Two further cases arose in the Krefeld area in November 2008, and there have since been multiple further reports from various regions in Germany and the neighboring countries.The authors report on the first six documented cases of infection with cowpox virus among young persons owning pet rats, with both typical and atypical clinical courses.The clinical, molecular biological, and serological findings confirmed cowpox virus infection in all six cases. The DNA sequence of the cowpox virus hemagglutinin gene was identical in all patients. The infections had arisen after direct contact with pet rats.Molecular genetic analysis of the cases described here suggests that the observed occurrence of cowpox virus infection among human beings and pet rats in multiple geographical areas represents a unitary epidemiological event that has not yet come under control. Further cases can be expected.

Interference effects among several commands offered by an experimental text editor were demonstrated. The experiment involved 24 computer novices correcting texts with a computer in several working sessions. The interference effects are interpreted as ‘fan-effects’, similar to those studied with propositional material (Anderson 1976). During the processing of editing tasks, increased latencies for key-strokes were observed with rising degrees of fan. Two sorts of fan degrees were manipulated in the experiment: Firstly, fan-effects arise if the same features of editing tasks occur for different commands (task fan). Secondly, fan-effects also arise if the same user action (e.g. key-stroke) is required for the execution of different commands (key fan). The mapping from task features to command names was varied. Consistent editors were compared to inconsistent ones. In consistent editors the same task features were mapped to the same key-strokes for different commands, while in inconsistent editors the mapping from task features to command keys was random. For consistent editors, interference due to fan is reduced as compared to inconsistent editors. The interference effects, as well as their qualitative dependence on consistency, point to functional equivalences among interference effects as observed here and as studied previously with propositional materials.

Well-characterized Group 14 Zintl anions were accessible by solution methods only in low yields up to now. An easy and inexpensive reaction route to polyanions, which starts from the elements, is admissible through the usage of [18]crown-6 as reaction medium at 40°C. The [K([18]crown-6)] unit proves to be an advantageous connecting device between intermetallic and organic networks. The title compound can be regarded as a supramolecular aggregate of a one-dimensional substructure of the composition K

[K(18-crown-6)]4[Pb9] was obtained by a novel synthetic procedure, which allows the generation of polyanions by direct reduction of the elements in molten crown ethers at temperatures slightly above 40 °C; the crystal structure refinement shows the coordination of three K atoms to the nonaplumbide anion.

Myeloproliferative disorders (MPD) are a heterogeneous group of diseases that involve chronic myeloid leukemia (CML), polycythemia vera (PV), essential trombocythemia (ET), chronic idiopatic myelofibrosis (IMF), hypereosinophilic syndrome and chronic neutrophilic leukemia. Recently, it has been found that in Ph-negative MPD, acquired somatic mutation in JAK2 gene can be identified, causing substitution of valine for phenylalanine at aminoacid position 617 (V617F). Experimental evidence indicates that JAK2 V617F might cause erythropoietin-independence of erythroid colonies and receptor hypersensitivity, thus be implicated in the pathogenesis of PV. The incidence of V617 in PV is high, reaching 96% of cases; in ET or IMF, the mutation is less frequent. Nevertheless, the percentage of JAK2 V617F-positive patients differs greatly among studies, depending on the detection technique used. Sequencing analysis, as one of the options, can underrate the number of positive cases, as its sensitivity in authentic samples with varying proportion of mutant granulocytes is unsatisfactory. The nucleotide context of the V617F site is complicated (direct repeat TGTG/TT), and thus prone to sequencing artifacts. For specific and sensitive detection of V617F mutation in JAK2 gene, we have developed a novel allelic discrimination assay, based on the usage of Real-Time PCR technology and LNA-modified fluorescently labeled probes (Locked Nucleic Acids). This technology is distinguished by 100% discrimination efficiency, and sensitivity detection rate reaching 10% of mutant granulocytes in an authentic sample. LNA-modified probes are extremely powerful tool for precise genotyping, since they are short (12-mers), and due to the interspersed LNA nucleotides, melting temperature (Tm) of the probe/target hybrid is high. Hence, the LNA-based genotyping technology combines the desired features of high sensitivity and absolute specificity. Herein, we present an analysis of JAK2 V617F detection in our group of 157 consecutive patients with the diagnosis of MPD or suspected MPD. Using our novel LNA-based Real-Time PCR genotyping technique, we were able to identify varying proportions of the mutant JAK2 allele in 87 cases (55.4%); in the remaining 70 patients the mutation was not detected. The LNA-based Real-Time PCR technique is extremely precise and efficient in identifying even subtle proportion of JAK2 V617F mutant granulocytes, which in cases of diagnostic uncertainties on the origin of the polycythemia might be of great importance.

Aus einem groseren Beobachtungsgut wurden bei Arbeitern des Quarzschieferbruchs in Krummendorf 35,8% Silikosen festgestellt und damit ein etwas niedrigerer Hundertsatz als vonGutzeit undGroetschel gefunden. Die Tuberkulosehaufigkeit bei den Angehorigen dieses Betriebes betragt 4,2%. Der Prozentsatz der Silikosen in den Munsterberger Ton- und Steinzeugwerken betragt 5,9 % gegenuber der durchschnittlichen Erkrankungshaufigkeit von 21–23% in der Porzellan- und Ziegeleiindustrie. Eine Vergesellschaftung mit Tuberkulose wurde bei unseren Beobachtungen im Gegensatz zu den meist hoher liegenden Zahlen in anderen Veroffentlichungen nur in 10–20% der Silikosen gefunden. Wir mussen in diesem Zusammenhang nochmals darauf hinweisen, das die gesamte Belegschaft der Munsterberger Ton- und Steinzeugwerke durch daa Schirmbildverfahren untersucht wurde und nur Werkangehorige mit krankhaftem Lungenbefund zur Begutachtung kamen. An Hand einer Tabelle wird auf die Beziehung zwischen Berufsalter und Grad der Silikose hingewiesen. Die klinischen Untersuchungsmethoden (Blutbild, Senkung, Spirometrie) sind nur bis zu einem bestimmten Grad fur die Diagnose und Beurteilung der Staublungenerkrankung verwertbar. Bezuglich der Senkung wird festgestellt, das, je schwerer eine Silikose ist, um so eher mit einer Senkungsbeschleunigung gerechnet werden kann, auch wenn keine Tuberkulose mit der Silikose verbunden ist. In weniger als der Halfte der Silikosen war der Spiroindex vermindert.

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