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This paper summaries a case study conducted by Meetingroom and Bank of Ireland in exploring the use of virtual reality to conduct meetings online. The case study was to compare virtual reality meetings to traditional video teleconferencing software. The results point to the improved feelings of presence, closeness, and arousal for virtual reality environments, but also demonstrate a difference in the experience for female and male participants. In particular, the use of avatars instead of real-life video images of the participants was preferred by female participants which point to a possible de-biasing ability for virtual reality environments.

With the advent of both modern X-ray fluorescence (XRF) methods and improved analytical reliability requirements the demand for suitable reference samples has increased. Especially in nanotechnology with the very low areal mass depositions, quantification becomes considerably more difficult. However, the availability of suited reference samples is drastically lower than the demand. Physical vapor deposition techniques have been enhanced significantly in the last decade driven by the need for extremely precise film parameters in multilayer production. We have applied those techniques for the development of layer-like reference samples with mass depositions in the ng-range and well below for Ca, Cu, Pb, Mo, Pd, Pb, La, Fe and Ni. Numerous other elements would also be possible. Several types of reference samples were fabricated: multi-elemental layer and extremely low (sub-monolayer) samples for various applications in XRF and total-reflection XRF analysis. Those samples were characterized and compared at three different synchrotron radiation beamlines at the BESSY II electron storage ring employing the reference-free XRF approach based on physically calibrated instrumentation. In addition, the homogeneity of the multi-elemental coatings was checked at the P04 beamline at DESY. The measurements demonstrate the high precision achieved in the manufacturing process as well as the versatility of application fields for the presented reference samples.

Efficient soft X-ray spectroscopy in the laboratory is still a challenging task. Here, we report on new toroidal multilayer optics designed and applied with the laser-produced plasma (LPP) source of the Berlin Laboratory for innovative X-ray technologies. The optics are described and characterized, and the application of the updated source to scanning-free grazing emission X-ray fluorescence is demonstrated on thermoelectric gold-doped copper oxide nanofilms. The comparison with synchrotron measurements allows estimating a flux on the sample of approximately 7.5 × 109 photons/s in the 1 keV range on a 100 µm × 100 µm spot, emphasizing the suitability of the updated LPP source for the application in photon hungry experiments. K.B. is most grateful for the scholarship from the International Max-Planck Research School at the Fritz Haber Institute. J.B. would like to thank the Excellence Initiative of the Deutsche Forschungsgemeinschaft for financial support.

This paper examines the use of Virtual Reality to conduct meetings online and compares them with an approach using traditional video teleconferencing software. The research was conducted using Virtual Reality meeting software and Skype for Business as test environments to compare a Virtual Reality meeting versus a Video conferencing environment. The results point to the improved feelings of presence, closeness, and arousal for Virtual Reality environments, but also demonstrate a difference in the experience for female and male participants. In particular, the use of Avatar’s instead of real-life video images of the participants was preferred by female participants which points to a possible de-biasing ability for Virtual Reality environments. The results also indicate a need to explore different interfaces designs and discuss the lessons learnt from the historical adoption of technology by the financial services community.

The European Integrated Activity of Excellence and Networking for nanoand Micro-Electronics Analysis (ANNA), www.ANNA-i3.net, has addressed the further development and assessment of methodologies for the detection of low concentration inorganic contaminants on and in silicon as well as for novel materials. The comparison of various analytical techniques available to the ANNA partners helped to identify the degree of comparableness of results revealed at different installations. The assessment of improved methodologies as well as the reliability of quantification and calibration procedures of specific analytical techniques such as Total-Reflection X-ray Fluorescence (TXRF) analysis has been of particular interest.

We investigated associations of markers of inflammation such as albumin, fibrinogen, C-reactive protein (CRP), and white blood cell count (WBCC) with future weight gain and weight loss in middle-aged adults in order to further elucidate the relationship between subclinical inflammation and weight change. Data were derived from the third population-based MONICA (Monitoring of Trends and Determinants in Cardiovascular Diseases) Augsburg survey (S3) conducted as part of the multinational World Health Organization MONICA project in 1994-1995 and a follow-up examination, to which all eligible subjects from S3 were invited in 2004-2005 (F3). In total, 2,792 persons (1,391 men, 1,401 women) aged 25-74 years at baseline were analyzed. Subjects with elevated concentrations of inflammatory markers were more prone to gain weight during follow-up. The odds ratios (OR) for a large mean annual weight gain (i.e., on average 1.02 kg/year) was 1.73 (95% confidence interval (CI) 1.27, 2.35) in fully adjusted analyses for subjects in the highest compared to the lowest quartile of fibrinogen. The respective ORs were 1.45 (95% CI, 1.08, 1.94) and 1.37 (95% CI, 1.03, 1.82) for CRP and WBCC. Stratified analyses revealed that associations were strongest among subjects who quitted smoking during the follow-up period (new quitters). Associations of inflammatory markers with large mean annual weight loss were weaker and became nonsignificant after multivariable adjustment. In conclusion, elevated levels of inflammatory markers are independently associated with weight gain in middle-aged adults, particularly among new quitters. This suggests that inflammation plays a key role in the process of weight gain, especially after smoking cessation.

We present a concept of a dedicated illumination to perform full-field X-ray microscopy with multilayer Laue lenses at laboratory X-ray sources. The basic idea is the application of a focusing X-ray multilayer mirror as condenser optics to provide a quasi-monochromatic and solid illumination, and consequently optimal conditions for the operation of the multilayer Laue lenses. First experimental results demonstrate the proof of this concept.

Geometrische Parameter wie Quellgrose und Blendengrosen, Abstande zwischen den einzelnen rontgenoptischen Komponenten und die charakteristischen Kenngrosen der strahlformenden Elemente beeinflussen die Winkel- und Energieauflosung in der experimentellen Anordnung der Rontgenreflektometrie. In Multischicht-Rontgenoptiken und Kristallmonochromatoren erfolgt die Kollimation und die Monochromatisierung entsprechend der BRAGG’schen Gleichung. Kristalle bestehen aus einem 3-dim. Gitter, in dem die streuenden Netzebenenen regelmasig angeordnet sind. Die Zahl der koharent streuenden Netzebenen ist sehr hoch. Deshalb sind Energie- und Winkelauflosung eines Kristallmonochromators um ca. eine Grosenordnung hoher als beim Multischichtsystem, welches als 1-dim. periodisches Gitter verstanden werden kann. Typisch fur eine Multischicht-Rontgenoptik ist eine Energieauflosung im Bereich ΔE/E = Δλ/λ von 10-1 bis 10-2. Demzufolge ist die Winkeldivergenz in der Grosenordnung zwischen 0.01° und 0.1° z. B. fur Cu Kα Strahlung. Allein mit Multischichtrontgenoptiken konnen Gesamtschichtdicken bis d = 270nm an Hand der Dickenoszillationen im Reflektogramm aufgelost werden. Oberhalb dieser Gesamtschichtdicke ist es erforderlich, die Winkeldivergenz durch Strahleinkopplung in einen Kristallmonochromator (CC) zu reduzieren und damit den auflosbaren Dickenbereich zu erhohen. Der Gewinn an Auflosung durch Kopplung einer Multischichtoptik und eines CC konnte am Beispiel einer 400nm Multischicht gezeigt werden. Thin film characterization by means of X-ray reflectometry X-ray reflectometry and diffractometry are widely used non-destructive methods to characterize thin films in the total thickness range which is typically between 2nm and approximately 500nm. On special arrangements a resolution up to 1000nm layer thickness has been demonstrated. Layer stack morphology, surface topography, layer structure, material density, single layer or period thickness and surface and interface roughness are the typical structural parameters both of single layers and of multilayers which can be described by the measured data. The performance of the measurement setup is mainly influenced by the parameters of the incident X-ray beam like beam divergence, monochromatism and photon energy. In the following the influence of the optical components in the beam path to angle and energy resolution of X-ray reflectometry is discussed.

Autonomically managing energy within the home is a formidable challenge, as any solution needs to interoperate with a decidedly heterogeneous network of sensors and appliances, not just in terms of technologies and protocols but also by managing smart as well as “dumb” appliances. Furthermore, as studies have shown that simply providing energy usage feedback to homeowners is inadequate in realising long-term behavioural change, autonomic energy management has the potential to deliver concrete and lasting energy savings without the need for user interventions. However, this necessitates that such interventions be performed in an intelligent and context-aware fashion, all the while taking into account system as well as user constraints and preferences. Thus, this chapter proposes the augmentation of home area networks with autonomic computing capabilities. Such networks seek to support opportunistic decision-making pertaining to the effective energy management within the home by seamlessly integrating a range of off-the-shelf sensor technologies with a software infrastructure for deliberation, activation, and visualisation.

Results of quantitative analysis of fluorescence x-ray absorption fine structure (XAFS) experiments at the FeK absorption edge are presented for a 6*(4.3 nm Fe/10.4 nm Al) multilayer prepared by pulsed laser deposition. Fluorescence XAFS experiments have been combined with excitation of prepared by pulsed laser deposition. Fluorescence XAFS experiments have been combined with excitation of x-ray standing waves. This combination in one experiment allowed for a depth-controlled excitation of Fe fluorescence and hence for a depth-resolved analysis of short-range order. Depth-resolved analysis showed that instead of sharp Fe/Al or Al/Fe interfaces extended interlayer regions exist. The structure retained that of bulk a-Fe. In the upper half of the Fe layer 37 at. % Al as nearest and next nearest neighbors of Fe were found, whereas in the lower half 80 at. % Al atoms occur. Thus the Fe/Al interface (deposition of Fe on Al)should be characterized by an intermixing zone significantly larger in comparison to that of the Al/Fe interface (deposition of Al on Fe).By conventional XAFS measurement carried out at a fixed angle of incidence of the exciting beam an average Fe neighborhood for the entire Fe layer of 58 at. % Al atoms was found. This value agrees with the average obtained when the analysis of the layer was performed separately for two sublayers by shifting the wave field through the layer.

Human-Robot Interaction poses significant research challenges. Recent research suggests that rsonalisation and individualisation are key factors for establishing lifelong human-robot relationships. This raises difficulties as roboticists seek to incorporate robots into the digital society where an creasing amount of human activities relies on digital technologies and ubiquitous infrastructures. In essence, a robot may be perceived as either an embedded or mobile artefact in an arbitrary environment that must be interacted with in a seamless and intuitive fashion. This chapter explores some of the ternative ways and the design ssues to achieve these objectives. Specifically, it describes a new system, which we call Mixed Reality Agent (MiRA) Chameleon, that combines the latest advancements on agent-based ubiquitous architectures with mixed reality technology to deliver personalised and ubiquitous robot agents.

To synthesize X-ray optical multilayers showing both high resolution and high reflectivity, spacer and absorber materials with low absorption coefficients for the desired spectral range are required. Beside the well-known candidates the material system Carbon / Carbon is interesting because of its low absorption coefficient over a wide spectral range and the opportunity, to deposit C-layers with different modifications, i.e. different optical properties. Simulations of C/C multilayers with different period thicknesses d and single layer densities ρ show, that reflectivities R (Cu Kα ) > 80% and a resolution ΔΘ≈0.002° can be achieved for C/C layer stacks with d= 3 nm and N= 1000 periods. An advanced large area Pulsed Laser Deposition (LA-PLD) technology was used to deposit C/C multilayers on Si-substrates up to 4" diameter. The carbon film growth conditions for the spacer and absorber layers were optimised by the variation of selected laser parameters like pulse energy and ablation wavelength, to achieve a sufficient density contrast and smooth interfaces. C/C multilayers with period thickness d= 1.1...7.0 nm and more than 500 periods were deposited. The X-ray optical performance of the C/C multilayers was characterized by means of X-ray reflectometry. A reflectivity R > 50 % (CuKα) was measured for C/C multilayers with d= 17.2 nm and N= 106 periods. A peak resolution (Δλ/λ) ≈ 1.1 % was obtained for a C/C multilayer structure with N= 80 periods and a period thickness d= 1.1nm. Results of TEM investigations indicate a regular morphology as well as smooth interfaces in the C-C layer stacks. Low compressive stresses were determined in C/C multilayers with different period thicknesses using X-ray diffraction techniques.

The evolution of intrinsic stress in multilayers and its behavior with growing number of periods and/or during radiation exposure, i.e. thermal treatment, becomes important in many X-ray optical applications. In Ni/C X-ray optical multilayers fabricated by pulsed laser deposition (PLD) at room temperature with typical period thickness d approx. 4.0 nm microstructure and intrinsic stress are analyzed with growing period number up to the layer stack delamination. Microstructure of single layers and interfaces and morphology of the total layer stack were investigated by means of transmission electron microscopy (TEM), X-ray reflectometry and diffraction. A clear indication of nano-crystallites was found for the Ni-layers, whereas the carbon layers were always amorphous. The diffraction pattern of a 300 period Ni/C layer stack hint at a hexagonal structure of the Ni crystallites with the (011)-lattice plane parallel to the Si substrate surface. Thus the elastic misfit between the Ni- and C-layers seems to be minimized. To investigate the evolution of stresses in the growing up Ni/C multilayers depth dependent stresses in the Si (100) substrate were analyzed using X-ray results of the stress tensor for Si-crystal of the substrate averaged over different penetration depths (0.6 and 3.6 μm). The found dependence of the substrate stresses on the total layer thickness point at low compressive stresses in the PLD-fabricated Ni/C X-ray optics in the range below -100 MPa at least up to a total layer thickness of 1200 nm (300 periods). An increase of the compressive stresses was obtained only for stacks of more than 300 periods. A delamination of the layer stack in part was observed at 900 periods.

Performance of Ni/C, Ni/B4C, Mo/B4C and W/B4C multilayers in the energy range E > 8 keV is considered by simulation of x-ray reflectivity and resolution of 1st order Bragg reflection at three different photon energies. The results indicate, that Ni/C and Ni/B4C multilayers show highest theoretical reflectivities of R > 80% for Cu K(alpha) - radiation and also above the Mo K-edge (E equals 20.04 keV) at 30 keV. For Mo K(alpha) -radiation a reflectivity of R > 90% can be achieved by the use of Mo/B4C multilayers. For applications, where period thicknesses d < 3 nm and high reflectivities are required W/B4C multilayers can be used. Theoretical values are compared with X-ray reflectometry results, which were executed at 75 period Ni/C, Ni/B4C and Mo/B4C multilayers, fabricated by pulsed laser deposition (PLD) technology on Si substrates. Amorphous or nanocrystalline structures of single layers, smoothest interfaces and high reproducibility of single layer thickness across the entire layer stack are the results of this high precision PLD process.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Verteilte Intrusion-Detection-Systeme (IDS) stellen ein zunehmend an Bedeutung gewinnendes Instrument fur den Schutz informationstechnischer Ressourcen dar. Durch die permanente Verarbeitung von Audit-Datensatzen mit (partiell) benutzeridentifizierenden Informationen entsteht allerdings ein datenschutzrechtliches Problem. Eine prinzipielle Losung dieses Problems ist moglich, indem Audit-Daten in pseudonymer Reprasentation ausgewertet werden. Dabei erfordert der Einsatz der fur die Pseudonymisierung und ggf. Depseudonymisierung notwendigen kryptographischen Verfahren ein leistungsfahiges Schlusselmanagement. Dieses mus nicht nur den konventionellen Anforderungen an ein Schlusselmanagement genugen, sondern auch der speziellen Arbeitsweise eines verteilten, pseudo-nymisierte Audit-Datensatze verarbeitenden EDS gerecht werden. Es besteht in erster Linie die Notwendigkeit, den in der Regel hohen Datendurchsatz nicht wesentlich zu beeinflussen. Auserdem ist ein besonders guter Schutz archivierter Schlussel erforderlich. Das im vorliegenden Beitrag beschriebene Konzept ist auf die Erfullung der genannten Anforderungen ausgerichtet. Es sieht die Verwendung allgemeiner Prinzipien, wie z.B. mehrere Schlusselhierarchien, konsequente Schlusselseparie-rung und die Nutzung von Kryptoperioden, vor. Ausgehend vom Ziel des Konzepts, der Verwaltung der Pseudonymisierungs- und Depseudonymisierungsschlussel, sind auserdem eine Reihe von speziellen Masnahmen notwendig, um den spezifischen Gegebenheiten der fur die prototypische Realisierung genutzten Systemumgebung zu entsprechen. Diese Umgebung besteht aus den Betriebssystemen Sun Solaris und Microsoft Windows NT sowie dem an der BTU Cottbus entwickelten Intrusion-Detection-System AID, das unter den genannten Betriebssystemen lauft und in das die Komponenten des Schlusselmanagements integriert wurden. Der Beitrag schliest mit einer Bewertung der erzielten Testresultate.

Periodic multilayers are well known as Bragg reflectors for X- rays. A high reflectivity and a wide reflection width are their outstanding features. However, if multilayers shall be used as reflective coating for X-ray optics, especially for wide acceptance angles, uniform layer thicknesses cause chromatic aberrations. These aberrations can be overcome by laterally graded multilayer optics. Their Bragg angle is matched laterally to the incidence angle so that for all points on the reflector, Bragg reflection is obtained for the same wavelength. Three major types of laterally graded multilayer mirrors ('Gobel Mirrors') are applied in X-ray diffractometry: (1) parabolic, (2) elliptic and (3) planar. In this paper, we give design criteria and formulae for these mirrors. Furthermore, we discuss the requirements on the dimensions and the fabrication process. Two different processes suitable for the fabrication, sputter coating and pulsed laser deposition (PLD), are described. The X-ray optical parameters and their characterization are presented for various mirrors designed for Cu K(alpha) , Mo K(alpha) and Cr K(alpha) radiation. From Ni/C and Ni/B4C multilayers, high-photon-flux monochromators with a Cu K(beta) /K(alpha) intensity ratio of about 1:1000 have been realized. The divergence of the 'parallel' beam reflected from parabolic mirrors is about 0.02 degrees, which is one order of magnitude lower than the divergence of polycapillary optics, monocapillary optics and waveguides. Comparing the photon flux density in a high resolution diffraction setup with and without mirror optics a gain factor of 16 was achieved for parabolic Ni/B4C multilayer mirrors.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The receptor-binding protein pb5(T5) of bacteriophage T5, when expressed from the oad gene cloned in pVK88 under the control of the phage T7 promoter/polymerase system, has been shown to bind to its FhuA receptor on the surface of E. coli, where it blocks FhuA for subsequent adsorption of T5 (Mondigler et al., FEMS Microbiol. Lett., 130, 293-300, 1995). In the present study the blocking assay has been applied to analyze the effects of several mutations within oad on the FhuA-binding properties of corresponding pb5 derivatives. Three classes of mutations were tested: (i) oad deletion derivatives, (ii) the oad mutation known to interfere with FhuA-binding of T5 (Heller and Bryniok, J. Virol., 49, 20-25, 1984), and (iii) linker-insertion mutations at a site very close to the oad mutation. Of the corresponding pb5 derivatives only one, a deletion derivative lacking the 153 C-terminal amino acids, was as active in the blocking assay as wild-type pb5(T5). All other derivatives were inactive or almost inactive. Isolation and molecular characterization of phenotypic revertants of T5oad showed that all revertants were true genotypic revertants of the oad mutation. The oad mutation has been identified as a G to T exchange resulting in a substitution of Gly for Trp at position 166 of pb5(T5). DNA sequencing of the hrs gene of bacteriophage BF23 and comparing the deduced amino acid sequence of pb5(BF23) with that of pb5(T5) revealed distinct regions of similarity and nonsimilarity. We propose that the receptor-binding region of pb5(T5) (pb5(BF23)) is formed by the region of nonsimilarity extending from amino acid position 89 (88) to position 305 (283).

Pulsed laser deposition is described as a technique for the synthesis of multilayers showing X- ray optical quality. The state of the art is characterized by results that demonstrate a development of the instrument basis superior to that of conventional PLD systems. Multilayers of the Ni/C, Mo/Si- and W/C-types prove the versatility of the method and the output of layer stack characterization by HREM, SPM, XD, AES, XPS, ellipsometry and image processing ensures a high quality with regard to stack regularity, layer homogeneity and interface smoothness.