Background information about Avian Infl uenza and hints for ornithologists

Wildvögel, v.a. Wassergeflügel, sind Reservoir für alle Influenzaviren. Von wirtschaftlicher Bedeutung sind die Subtypen H5 und H7, während H1, H2 und H3 Erreger der Humangrippe sind. Diese niedrig pathogenen Vogelgrippeviren verursachen normalerweise bei infi zierten Vögeln keine klinischen Symptome. Nach Transfer niedrig pathogener Vogelgrippeviren in Geflügelhaltungen mit den daraus resultierenden, rasch aufeinander folgenden Virenzyklen durch rasche Vogelpassagen und sofortige Neuinfektion kann sich ein solches niedrig pathogenes Virus jedoch in ein hoch pathogenes Vogelgrippevirus (HPAI-Virus) umwandeln. Diese hoch pathogenen Viren können dann sowohl wieder über Wildvögel, als auch über Transport kontaminierter Vögel, Gefl ügelprodukte und Materialien sowie über Wasser weiterverbreitet werden. Der aktuelle, große Ausbruch der Gefl ügelgrippe geht auf den HPAI-Virus H5N1 zurück, der vermutlich in den späten 1990er Jahren in Hausenten in Südchina entstanden ist. Im Jahr 2005 begann diese Krankheit, sich von Südostasien aus westwärts zu verbreiten und trat damit als direkte Bedrohung für europäische Geflügelbestände in Erscheinung. Außerdem wurden einige wenige menschliche Fälle einer HPAI H5N1-Erkrankung aus Südostasien gemeldet. Alle diese menschlichen Erkrankungen standen mit sehr engen Kontakten zu oder Verspeisen von infizierten Tieren (vor allem Hühner, Enten und Schweine) in Verbindung und eine mögliche Mensch-zu-Mensch-Übertragung wird noch kontrovers diskutiert. Obwohl die Vogelgrippe nach wie vor eine Geflügelkrankheit ist, besteht die Möglichkeit, dass sich das Virus in seiner genetischen Struktur – z.B. durch Vermischung mit einem Humangrippevirus – so verändern kann, dass es leicht zwischen Menschen übertragen werden kann und bei diesen auf ein weitgehend unvorbereitetes Immunsystem trifft. Obwohl sich die Wahrscheinlichkeit einer solchen Veränderung nicht abschätzen lässt, liefern drei Pandemien im 20 Jahrhundert, die alle auf mutierte Vogelgrippeviren zurückzuführen sind, genug Anlass zur sorgfältigen Beobachtung der momentanen Lage.Waterfowl are known to be the major reservoir for all 16 H- and 9 N- Subtypes of low pathogenic avian infl uenza viruses (LPAIV), including the subtypes H5 and H7 being a serious economic threat to the poultry industry as well as H1, H2, H3 that are the main source for human infl uenza. LPAI neither cause any signs of disease in the infected wild birds nor in poultry. However, low pathogenic avian infl uenza virus of the subtypes H5 and H7 can be introduced into poultry holdings. Especially in industrial holdings with large numbers of highly susceptible animals, the previously stable viruses of low pathogenicity begin to evolve rapidly and may mutate into highly pathogenic avian infl uenza (HPAI) (known as fowl plague and also called „bird flu“) causing up to 100% mortatlity in infected birds. Aft erwards, infections of HPAI are usually spread by movement of stock, infectious feces, contaminated water or bird products. Free fl ying birds are usually also blamed to spread the disease, but this could be never proven to have happened. Since 1959 none of the outbreaks of HPAI has approached the size of the ongoing epizootic in Southeast Asia, which most probably originated in the late 1990 ies presumbly in captured ducks in Southern China and is caused by a new HPAI virus of the subtype H5N1. In 2005 the disease started to spread westwards and appears to be a threat for European poultry. Th e asian H5N1 cause serious public health concern for at least three reasons. Th ese AIV isolates can cause heavy economic losses in the poultry industry and through loss of poultry may exaggerate to human food protein defi cits in the developing world. In addition, they have the potential to cross the species barriers and cause human disease and death though only when connected to very close contacts with infected animals or raw consumption of infected birds (chicken, ducks). Last but not least there is the potential of the virus to change it‘s genetic structure – most probably by mixing with a human infl uenza virus (H1, H2, H3) that may achieve human-to-human spread by meeting the unprepared immune system of men resulting in a new human pandemia. Th ree pandemias during the 20 th century – all originating from HPAI viruses- emphasise the danger of the probability of H5N1 becoming the next pandemia virus

Probing atom-surface interactions by diffraction of Bose-Einstein condensates

In this article we analyze the Casimir-Polder interaction of atoms with a solid grating and an additional repulsive interaction between the atoms and the grating in the presence of an external laser source. The combined potential landscape above the solid body is probed locally by diffraction of Bose-Einstein condensates. Measured diffraction efficiencies reveal information about the shape of the Casimir-Polder interaction and allow us to discern between models based on a pairwise-summation (Hamaker) approach and Lifshitz theory.Comment: 5 pages, 4 figure

Usutu Virus as cause of mass mortality in Blackbirds Turdus merula and other bird species in Europe: experiences from five outbreaks between 2001 and 2011

Das Usutu-Virus (USUV) ist ein durch Stechmücken der Gattung Culex übertragenes Flavivirus. Es wurde wahrscheinlich durch Zugvögel oder Stechmücken nach Europa eingeschleppt und hat sich inzwischen dauerhaft in der einheimischen Stechmücken-und Vogelfauna etabliert. Seit seinem Erstnachweis 2001 in Österreich hat das USUV fünf größere Ausbrüche mit USUV-assoziierten Vogelsterben, vor allem unter Amseln und in Volieren gehaltenen Eulen, sowie vermutlich kleinere Ausbrüche ohne augenfälliges Vogelsterben verursacht. In unserer Übersicht stellen wir das aktuelle Wissen zum Erreger, den Stechmücken als Vektoren und den Vögeln als Hauptwirten vor. Die Auswertung bislang publizierter Studien ergab, dass in der letzten Dekade in Europa, im Zusammenhang mit USUV-Ausbrüchen, über 3050 Vogelindividuen aus 129 Arten und unterschiedlichsten Ordnungen auf USUV-Infektionen untersucht worden sind. Davon wurden 48 Arten positiv getestet, überwiegend Singvögel, Eulen und Greifvögel. Am häufigsten war die Amsel, danach Haussperling, Mönchsgrasmücke, Bart- und Habichtskauz betroffen. Unter den 48 USUV-positiven Arten betrafen 39 frei lebende und neun in Gefangenschaft gehaltene Arten. Mögliche Ausbreitungswege des Erregers von Afrika nach Europa sowie innerhalb Europas werden diskutiert. Amseln und andere Singvögel sind anscheinend besonders anfällig für USUV. Möglicherweise sind sie zur Hauptflugzeit der Stechmücken aufgrund ihres Mauser- und Ernährungszustandes immungeschwächt und anfälliger für einen Virenbefall.Usutu virus (USUV) is a flavivirus transmitted by mosquitoes of the genus Culex. USUV was presumably introduced into Europe through migrating birds or mosquitoes during the last ten years. USUV established stable transmission cycles in Europe between mosquitos and hosts and is able to hibernate within Europe. Since the first record in 2001 in Austria, USUV caused five larger outbreaks with USUV-induced mass mortalities, especially on Blackbirds and captive owls, and probably a number of smaller outbreaks without recorded mass mortality. In our review we compile the up-to-date knowledge about the agent, the mosquitos as vectors and the birds as main hosts. A review of published studies revealed a total of 3050 bird individuals from 129 species and a wide variety of orders that have been tested for USUV during the last decade in Europe in connection with USUV outbreaks. Out of these, 48 species have been tested positively – mainly songbirds incl. crows (24 species), owls and birds of prey (9 species). Most cases concerned Blackbird, followed by House Sparrow, Blackcap, Great Grey Owl and Ural Owl. Among the 48 species tested positively, 39 concerned free living individuals and nine concerned captive individuals. Potential ways of propagation of USUV from Africa into Europe as well as inside Europe are discussed. Blackbirds seem to be especially perceptive to USUV. With regard to their species-specific biology we try to give an explanation for this phenomenon: presumably, Blackbirds have a weak immune system due to moult and nutrition state during the main flight period of the mosquitoes and are thus more perceptive to virus attacks

Purcell-induced suppression of superradiance for molecular overlayers on noble atom surfaces

We study the impact of an environment on the electromagnetic responses of a molecule in the presence of a dielectric medium. By applying the dipole-dipole coupling between the molecule's and the environment's degrees of freedom, we can reduce the complex system into its components and predict excitation lifetimes of single and few molecules attached to a dielectric surface by knowing the entire quantum-mechanical properties of the molecules, such as transition energies and dipole moments. The derived theory allows for the description of superradiance between two molecules depending on the geometric arrangement between both concerning their separation and orientation with respect to each other. We analyse the possibility of superradiance between two molecules bound to a dielectric sphere and determine a change of the relevant length scale where the usually considered wavelength in free space is replaced with the binding distance, drastically reducing the length scales at which collective effects can take place

Spectroscopy on nanoparticles without light

One of the most important tools in modern science is the analysis of electromagnetic properties via spectroscopy. The various types of spectroscopy can be classified by the underlying type of interactions between energy and material. In this paper we demonstrate a new class of spectroscopy based on Casimir interactions between a solid investigated object and a reference surface embedded in an environmental liquid medium. Our main example is based on the measurement of Hamaker constants upon changing the concentration of an intervening two-component liquid, where we demonstrate a possible reconstruction algorithm to estimate the frequency-dependent dielectric function of the investigated particle

Identification of subpopulations with characteristics of mesenchymal progenitor cells from human osteoarthritic cartilage using triple staining for cell surface markers

We first identified and isolated cellular subpopulations with characteristics of mesenchymal progenitor cells (MPCs) in osteoarthritic cartilage using fluorescence-activated cell sorting (FACS). Cells from osteoarthritic cartilage were enzymatically isolated and analyzed directly or after culture expansion over several passages by FACS using various combinations of surface markers that have been identified on human MPCs (CD9, CD44, CD54, CD90, CD166). Culture expanded cells combined and the subpopulation derived from initially sorted CD9(+), CD90(+), CD166(+ )cells were tested for their osteogenic, adipogenic and chondrogenic potential using established differentiation protocols. The differentiation was analyzed by immunohistochemistry and by RT-PCR for the expression of lineage related marker genes. Using FACS analysis we found that various triple combinations of CD9, CD44, CD54, CD90 and CD166 positive cells within osteoarthritic cartilage account for 2–12% of the total population. After adhesion and cultivation their relative amount was markedly higher, with levels between 24% and 48%. Culture expanded cells combined and the initially sorted CD9/CD90/CD166 triple positive subpopulation had multipotency for chondrogenic, osteogenic and adipogenic differentiation. In conclusion, human osteoarthritic cartilage contains cells with characteristics of MPCs. Their relative enrichment during in vitro cultivation and the ability of cell sorting to obtain more homogeneous populations offer interesting perspectives for future studies on the activation of regenerative processes within osteoarthritic joints

Managing Organizational Cyber Security – The Distinct Role of Internalized Responsibility

Desirable user behavior is key to cyber security in organizations. However, a comprehensive overview on how to manage user behavior effectively, in order to support organizational cyber security, is missing. Building on extant research to identify central components of organizational cyber security management and on a qualitative analysis based on 20 semi-structured interviews with users and IT-Managers of a European university, we present an integrated model on this issue. We contribute to understanding the interrelations of namely user awareness, user IT-capabilities, organizational IT, user behavior, and especially internalized responsibility and relation to organizational cyber security

Information structure

The guidelines for Information Structure include instructions for the annotation of Information Status (or ‘givenness’), Topic, and Focus, building upon a basic syntactic annotation of nominal phrases and sentences. A procedure for the annotation of these features is proposed

Orientational dependence of the van der Waals interactions for finite-sized particles

Van der Waals forces as interactions between neutral and polarisable particles act at small distances between two objects. Their theoretical origin lies in the electromagnetic interaction between induced dipole moments caused by the vacuum fluctuations of the ground-state electromagnetic field. The resulting theory well describes the experimental situation in the limit of the point dipole assumption. At smaller distances, where the finite size of the particles has to be taken into account, this description fails and has to be corrected by higher orders of the multipole expansion, such as quadrupole moments and so on. With respect to the complexity of the spatial properties of the particles this task requires a considerable effort. In order to describe the van der Waals interaction between such particles, we apply the established method of a spatially spread out polarisability distribution to approximate the higher orders of the multipole expansion. We hence construct an effective theory for effects from anisotropy and finite size on the van der Waals potential