123 research outputs found

    Evaluation of antigens for the serodiagnosis of kala-azar and oriental sores by means of the indirect immunofluorescence antibody test (IFAT)

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    Antigens and corresponding sera were collected from travellers with leishmaniasis returning to Germany from different endemic areas of the old world. The antigenicity of these Leishmania strains, which were maintained in Syrian hamsters, was compared by indirect immunofluorescence (IFAT). Antigenicity was demonstrated by antibody titres in 18 sera from 11 patients. The amastigotic stages of nine strains of Leishmania donovani and four strains of Leishmania tropica were compared with each other and with the culture forms of insect flagellates (Strigomonas oncopelti and Leptomonas ctenocephali). Eighteen sera from 11 patients were available for antibody determination with these antigens. The maximal antibody titres in a single serum varied considerably depending on which antigen was used for the test. High antibody levels could only be maintained when Leishmania donovani was employed as the antigen, but considerable differences also occurred between the different strains of this species. The other antigens were weaker. No differences in antigenicity between amastigotes and promastigotes of the same strain were observed. It is important to select suitable antigens. Low titres may be of doubtful specificity and are a poor baseline for the fall in titre which is an essential index of effective treatment.Wir sammelten Parasiten und Seren von Reisenden, die aus verschiedenen endemischen Gebieten der Alten Welt mit einer Leishmaniasis nach Deutschland zurückkehrten. Die Antigenaktivitäten der isolierten und fortlaufend in Goldhamstern gehaltenenLeishmania-Stämme wurden im indirekten Immunofluoreszenztest (IFAT) verglichen. Die Antigenität wurde an Hand von Antikörpertitern in 18 Serumproben von 11 Patienten bewiesen. Neun Stämme desLeishmania donovani-Komplexes und vierLeishmania tropica-Isolate wurden in ihrem amastigoten Stadium miteinander verglichen. Hinzu kamen zwei Insekten-Flagellaten als Kulturformen:Strigomonas oncopelti undLeptomonas ctenocephali. 18 Serumproben von 11 Patienten standen für die Antikörperbestimmung mit diesen Antigenen zur Verfügung. Die maximalen Titerhöhen variierten in ein- und derselben antiserumprobe zum Teil erheblich, je nachdem, welches Antigen für den Test benutzt wurde. Hohe Antikörpertiter konnten nur erhalten werden, wennLeishmania donovani als Antigen vorlag, es ergaben sich aber auch zwischen den einzelnen Stämmen dieser Leishmaniaart erhebliche Unterschiede in der Antigenaktivität. Antigene anderer Art erwiesen sich als wenig wirksam. Zwischen amastigoten und promastigoten Entwicklungsformen einesLeishmania donovani-Stammes konnten keine Unterschiede in der Antigenaktivität erkannt werden. Für den Nachweis möglichst hoher Antikörpertiter im IFAT ist die Auswahl geeigneter Antigene von ausschlaggebender Bedeutung. Niedrige Titer erschweren deren Beurteilung als spezifisch und sind eine schlechte Ausgangsposition für die Beobachtung des obligatorischen Titerabfalles nach erfolgreicher Therapie

    Network slicing to enable scalability and flexibility in 5G mobile networks

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    We argue for network slicing as an efficient solution that addresses the diverse requirements of 5G mobile networks, thus provid-ing the necessary flexibility and scalability associated with future network implementations. We elaborate on the challenges that emerge when we design 5G networks based on network slicing. We focus on the architectural aspects associated with the coexistence of dedicated as well as shared slices in the network. In particular, we analyze the realization options of a flexible radio access network with focus on network slicing and their impact on the design of 5G mobile networks. In addition to the technical study, this paper provides an investigation of the revenue potential of network slicing, where the applications that originate from such concept and the profit capabilities from the network operator's perspective are put forward.This work has been performed in the framework of the H2020-ICT-2014-2 project 5G NORMA

    Cystic lymph node metastases of squamous cell carcinoma of Waldeyer's ring origin

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    We analysed in a retrospective study the frequency of cystic lymph node (LN) metastases in neck dissection specimens of 123 patients with primary squamous cell carcinoma (SCC) arising in the palatine tonsils (62 M/14 F), the base of the tongue (38 M/5 F) and the nasopharynx (2 M/2 F). Eighty-two per cent of patients had metastases (64 tonsillar SCC, 33 base of tongue SCC and all four nasopharynx SCC) in 368 LN of a total 2298 sampled LN. Thirty-nine per cent of patients had exclusively solid metastases and 37% of patients had exclusively cystic metastases. A total of 62 patients had some signs of cyst formation in one or more metastatically affected LN (27 with only histological evidence of cyst formation with luminal diameters < 5 mm, 35 with clinically detectable cyst with luminal diameter > 5 mm). Cystic metastases were more common in patients with SCC of the base of the tongue (P = 0.005), while solitary clinically evident cystic metastasis with lumina > 5 mm were found exclusively in tonsillar carcinoma (P = 0.024). In comparison with solid metastases, cyst formation was associated with N-categories (N2b and N3, P = 0.005) in SCC of the base of the tongue origin. No such association was observed for tonsillar SCC (P = 0.65). The primary mechanism of cyst formation was cystic degeneration. © 1999 Cancer Research Campaig

    Effect of heating rate on the crack formation during baking in carbon anodes used in aluminum industry

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    The quality of carbon anodes used in aluminum industry depends on the raw material properties and the manufacturing process parameters. It is one of the key factors directly related to the aluminum production cost. The degradation in anode quality such as crack formation increases the energy consumption, the environmental emissions, and the smelter’s overall operating cost. The objective of this work is to investigate the formation of cracks in several industrial green anode samples during baking at different heating rates and to determine the influence of this baking parameter on the crack formation. The samples were characterized before and after baking by measuring a number of physical properties (electrical resistivity, density, etc.) which define the final quality of the anode samples. Also, techniques based on ultra-sound and scanning electron microscopy were used to determine the extent of cracking after baking

    Feasibility studies for the measurement of time-like proton electromagnetic form factors from p¯ p→ μ+μ- at P ¯ ANDA at FAIR

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    This paper reports on Monte Carlo simulation results for future measurements of the moduli of time-like proton electromagnetic form factors, | GE| and | GM| , using the p¯ p→ μ+μ- reaction at P ¯ ANDA (FAIR). The electromagnetic form factors are fundamental quantities parameterizing the electric and magnetic structure of hadrons. This work estimates the statistical and total accuracy with which the form factors can be measured at P ¯ ANDA , using an analysis of simulated data within the PandaRoot software framework. The most crucial background channel is p¯ p→ π+π-, due to the very similar behavior of muons and pions in the detector. The suppression factors are evaluated for this and all other relevant background channels at different values of antiproton beam momentum. The signal/background separation is based on a multivariate analysis, using the Boosted Decision Trees method. An expected background subtraction is included in this study, based on realistic angular distributions of the background contribution. Systematic uncertainties are considered and the relative total uncertainties of the form factor measurements are presented

    PANDA Phase One - PANDA collaboration

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    The Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany, provides unique possibilities for a new generation of hadron-, nuclear- and atomic physics experiments. The future antiProton ANnihilations at DArmstadt (PANDA or P¯ANDA) experiment at FAIR will offer a broad physics programme, covering different aspects of the strong interaction. Understanding the latter in the non-perturbative regime remains one of the greatest challenges in contemporary physics. The antiproton–nucleon interaction studied with PANDA provides crucial tests in this area. Furthermore, the high-intensity, low-energy domain of PANDA allows for searches for physics beyond the Standard Model, e.g. through high precision symmetry tests. This paper takes into account a staged approach for the detector setup and for the delivered luminosity from the accelerator. The available detector setup at the time of the delivery of the first antiproton beams in the HESR storage ring is referred to as the Phase One setup. The physics programme that is achievable during Phase One is outlined in this paper
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