SrAlSi4N7:Eu2+

The new nitridoalumosilicate phosphor SrAlSi4N7:Eu2+ has been synthesized under nitrogen atmosphere at temperatures up to 1630°C in a radio-frequency furnace starting from Sr metal, α-Si3N4, AlN, and additional Eu metal. The crystal structure of the host compound SrAlSi4N7 has been solved and refined on the basis of single-crystal and powder X-ray diffraction data. In the solid, there is a network structure of corner-sharing SiN4 tetrahedra incorporating infinite chains of all edge-sharing AlN4 tetrahedra running along [001] (SrAlSi4N7: Pna21 (No. 33), Z = 8, a = 11.742(2) Å, b = 21.391(4) Å, c = 4.966(1) Å, V = 12.472(4) Å3, 2739 reflections, 236 refined parameters, R1 = 0.0366). The Eu2+-doped compound SrAlSi4N7:Eu2+ shows typical broadband emission originating from dipole-allowed 4f6(7FJ)5d1 → 4f7 (8S7/2) transitions in the orange-red spectral region (λmax = 632 nm for 2% Eu doping level, 450 nm excitation) with a spectral width of FWHM = 2955 (± 75) cm−1 and a Stokes shift ΔS = 4823 (± 100) cm−1. The luminescence properties make the phosphor an attractive candidate material as red component in trichromatic warm white light LEDs with excellent color rendition properties

Key signal contributions in photothermal deflection spectroscopy

We report on key signal contributions in photothermal deflection spectroscopy (PDS) of semiconductors at photon energies below the bandgap energy and show how to extract the actual absorption properties from the measurement data. To this end, we establish a rigorous computation scheme for the deflection signal including semi-analytic raytracing to analyze the underlying physical effects. The computation takes into account linear and nonlinear absorption processes affecting the refractive index and thus leading to a deflection of the probe beam. We find that beside the linear mirage effect, nonlinear absorption mechanisms make a substantial contribution to the signal for strongly focussed pump beams and sample materials with high two-photon absorption coefficients. For example, the measured quadratic absorption contribution exceeds 5% at a pump beam intensity of about ${1.3}\times{10^{5}}\;{W}/{cm^{2}}$ in Si and at ${5}\times{10^{4}}\;{W}/{cm^{2}}$ in GaAs. In addition, our method also includes thermal expansion effects as well as spatial gradients of the attenuation properties. We demonstrate that these effects result in an additional deflection contribution which substantially depends on the distance of the photodetector from the readout point. This distance dependent contribution enhances the surface related PDS signal up to two orders of magnitude and may be misinterpreted as surface absorption if not corrected in the analysis of the measurement data. We verify these findings by PDS measurements on crystalline silicon at a wavelength of 1550 nm and provide guidelines how to extract the actual attenuation coefficient from the PDS signal.Comment: 10 pages, 16 figures, submitted to Journal of Applied Physiv

Example-based wrinkle synthesis for clothing animation

This paper describes a method for animating the appearance of clothing, such as pants or a shirt, that fits closely to a figure's body. Compared to flowing cloth, such as loose dresses or capes, these types of garments involve nearly continuous collision contact and small wrinkles, that can be troublesome for traditional cloth simulation methods. Based on the observation that the wrinkles in closefitting clothing behave in a predominantly kinematic fashion, we have developed an example-based wrinkle synthesis technique. Our method drives wrinkle generation from the pose of the figure's kinematic skeleton. This approach allows high quality clothing wrinkles to be combined with a coarse cloth simulation that computes the global and dynamic aspects of the clothing motion. While the combined results do not exactly match a high-resolution reference simulation, they do capture many of the characteristic fine-scale features and wrinkles. Further, the combined system runs at interactive rates, making it suitable for applications where high-resolution offline simulations would not be a viable option. The wrinkle synthesis method uses a precomputed database built by simulating the high-resolution clothing as the articulated figure is moved over a range of poses. In principle, the space of poses is exponential in the total number of degrees of freedom; however clothing wrinkles are primarily affected by the nearest joints, allowing each joint to be processed independently. During synthesis, mesh interpolation is used to consider the influence of multiple joints, and combined with a coarse simulation to produce the final results at interactive rates

Impacts of feeding less food-competing feedstuffs to livestock on global food system sustainability

Funding Christian Schader, Adrian Muller, Nadia El-Hage Scialabba, Judith Hecht, Anne Isensee, Harinder P.S. Makkar, Peter Klocke, Florian Leiber, Matthias Stolze, Urs Niggli thank FAO for funding this research. K.E. gratefully acknowledges funding from ERC-2010-Stg-263522 LUISE. Additional data and method details are provided in the supplementary materials. The contribution of P.S. is supported by funding from the Belmont Forum-FACCE-JPI Project ‘Delivering Food on Limited Land’ (DEVIL), with the UK contribution supported by NERC (NE/M021327/1).Peer reviewedPublisher PD

Der Studien- und Berufserfolg von (angehenden) Lehrkräften in Österreich im Längsschnitt – Ausgewählte Befunde aus dem ersten Studienjahr

Es wird eine Längsschnittstudie vorgestellt, in der zwei Kohorten von Studierenden vom Aufnahmeverfahren beginnend über den Verlauf des Studiums bis in den Beruf begleitet werden. Über jeweils fünf Jahre hinweg sollen Studienerfolg und Praxiserfahrungen erhoben und in Beziehung zu den Ergebnissen des Aufnahmeverfahrens gesetzt werden. In diesem Beitrag werden neben der Konzeption der Studie Ergebnisse einer Nacherhebung im ersten Semester präsentiert (Nt2 = 781, Nt2a = 241), die darauf hinweisen, dass von den erhobenen Merkmalen vor allem die Sprachkompetenz und bestimmte Persönlichkeitsmerkmale prädiktiv für die Studienleistungen und die Zufriedenheit mit der Studien- und Berufswahl sind

Twin study reveals non-heritable immune perturbations in multiple sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disorder of the central nervous system underpinned by partially understood genetic risk factors and environmental triggers and their undefined interactions$^{1,2}$. Here we investigated the peripheral immune signatures of 61 monozygotic twin pairs discordant for MS to dissect the influence of genetic predisposition and environmental factors. Using complementary multimodal high-throughput and high-dimensional single-cell technologies in conjunction with data-driven computational tools, we identified an inflammatory shift in a monocyte cluster of twins with MS, coupled with the emergence of a population of IL-2 hyper-responsive transitional naive helper T cells as MS-related immune alterations. By integrating data on the immune profiles of healthy monozygotic and dizygotic twin pairs, we estimated the variance in CD25 expression by helper T cells displaying a naive phenotype to be largely driven by genetic and shared early environmental influences. Nonetheless, the expanding helper T cells of twins with MS, which were also elevated in non-twin patients with MS, emerged independent of the individual genetic makeup. These cells expressed central nervous system-homing receptors, exhibited a dysregulated CD25–IL-2 axis, and their proliferative capacity positively correlated with MS severity. Together, our matched-pair analysis of the extended twin approach allowed us to discern genetically and environmentally determined features of an MS-associated immune signature

Example-based wrinkle synthesis for clothing animation

This paper describes a method for animating the appearance of clothing, such as pants or a shirt, that fits closely to a figure's body. Compared to flowing cloth, such as loose dresses or capes, these types of garments involve nearly continuous collision contact and small wrinkles, that can be troublesome for traditional cloth simulation methods. Based on the observation that the wrinkles in closefitting clothing behave in a predominantly kinematic fashion, we have developed an example-based wrinkle synthesis technique. Our method drives wrinkle generation from the pose of the figure's kinematic skeleton. This approach allows high quality clothing wrinkles to be combined with a coarse cloth simulation that computes the global and dynamic aspects of the clothing motion. While the combined results do not exactly match a high-resolution reference simulation, they do capture many of the characteristic fine-scale features and wrinkles. Further, the combined system runs at interactive rates, making it suitable for applications where high-resolution offline simulations would not be a viable option. The wrinkle synthesis method uses a precomputed database built by simulating the high-resolution clothing as the articulated figure is moved over a range of poses. In principle, the space of poses is exponential in the total number of degrees of freedom; however clothing wrinkles are primarily affected by the nearest joints, allowing each joint to be processed independently. During synthesis, mesh interpolation is used to consider the influence of multiple joints, and combined with a coarse simulation to produce the final results at interactive rates

Homology-based inference sets the bar high for protein function prediction

Background: Any method that de novo predicts protein function should do better than random. More challenging, it also ought to outperform simple homology-based inference. Methods: Here, we describe a few methods that predict protein function exclusively through homology. Together, they set the bar or lower limit for future improvements. Results and conclusions: During the development of these methods, we faced two surprises. Firstly, our most successful implementation for the baseline ranked very high at CAFA1. In fact, our best combination of homology-based methods fared only slightly worse than the top-of-the-line prediction method from the Jones group. Secondly, although the concept of homology-based inference is simple, this work revealed that the precise details of the implementation are crucial: not only did the methods span from top to bottom performers at CAFA, but also the reasons for these differences were unexpected. In this work, we also propose a new rigorous measure to compare predicted and experimental annotations. It puts more emphasis on the details of protein function than the other measures employed by CAFA and may best reflect the expectations of users. Clearly, the definition of proper goals remains one major objective for CAFA