2017, Szwed, Małgorzata, Pin´skwar, Iwona, Kundzewicz, Zbigniew W., Graczyk, Dariusz, Mezghani, Abdelkader

The present paper examines variability of characteristics of snow cover (snow cover depth, number of days with snow cover and dates of beginning and end of snow cover) in Poland. The study makes use of a set of 43 long time series of observation records from the stations in Poland, from 1952 to 2013. To describe temporal changes in snow cover characteristics, the intervals of 1952–1990 and of 1991–2013 are compared and trends in analysed data are sought (e.g., using the Mann–Kendall test). Observed behaviour of time series of snow-related variables is complex and not easy to interpret, for instance because of the location of the research area in the zone of transitional moderate climate, where strong variability of climate events is one of the main attributes. A statistical link between the North Atlantic Oscillation (NAO) index and the snow cover depth, as well as the number of snow cover days is found.

2017, Nagendra, Baku, Rosely, C. V. Sijla, Leuteritz, Andreas, Reuter, Uta, Gowd, E. Bhoje

Sonication-assisted delamination of layered double hydroxides (LDHs) resulted in smaller-sized LDH nanoparticles (∼50-200 nm). Such delaminated Co-Al LDH, Zn-Al LDH, and Co-Zn-Al LDH solutions were used for the preparation of highly dispersed isotactic polypropylene (iPP) nanocomposites. Transmission electron microscopy and wide-angle X-ray diffraction results revealed that the LDH nanoparticles were well dispersed within the iPP matrix. The intention of this study is to understand the influence of the intralayer metal composition of LDH on the various properties of iPP/LDH nanocomposites. The sonicated LDH nanoparticles showed a significant increase in the crystallization rate of iPP; however, not much difference in the crystallization rate of iPP was observed in the presence of different types of LDH. The dynamic mechanical analysis results indicated that the storage modulus of iPP was increased significantly with the addition of LDH. The incorporation of different types of LDH showed no influence on the storage modulus of iPP. But considerable differences were observed in the flame retardancy and thermal stability of iPP with the type of LDH used for the preparation of nanocomposites. The thermal stability (50% weight loss temperature (T0.5)) of the iPP nanocomposite containing three-metal LDH (Co-Zn-Al LDH) is superior to that of the nanocomposites made of two-metal LDH (Co-Al LDH and Zn-Al LDH). Preliminary studies on the flame-retardant properties of iPP/LDH nanocomposites using microscale combustion calorimetry showed that the peak heat release rate was reduced by 39% in the iPP/Co-Zn-Al LDH nanocomposite containing 6 wt % LDH, which is higher than that of the two-metal LDH containing nanocomposites, iPP/Co-Al LDH (24%) and iPP/Zn-Al LDH (31%). These results demonstrated that the nanocomposites prepared using three-metal LDH showed better thermal and flame-retardant properties compared to the nanocomposites prepared using two-metal LDH. This difference might be due to the better char formation capability of three-metal LDH compared to that of two-metal LDH.

2017, Wang, Tao, Li, Peining, Chigrin, Dmitry N., Giles, Alexander J., Bezares, Francisco J., Glembocki, Orest J., Caldwell, Joshua D., Taubner, Thomas

A conventional thermal emitter exhibits a broad emission spectrum with a peak wavelength depending upon the operation temperature. Recently, narrowband thermal emission was realized with periodic gratings or single microstructures of polar crystals supporting distinct optical modes. Here, we exploit the coupling of adjacent phonon-polaritonic nanostructures, demonstrating experimentally that the nanometer-scale gaps can control the thermal emission frequency while retaining emission line widths as narrow as 10 cm-1. This was achieved by using deeply subdiffractional bowtie-shaped silicon carbide nanoantennas. Infrared far-field reflectance spectroscopy, near-field optical nanoimaging, and full-wave electromagnetic simulations were employed to prove that the thermal emission originates from strongly localized surface phonon-polariton resonances of nanoantenna structures. The observed narrow emission line widths and exceptionally small modal volumes provide new opportunities for the user-design of near- and far-field radiation patterns for advancements in infrared spectroscopy, sensing, signaling, communications, coherent thermal emission, and infrared photodetection. © 2017 American Chemical Society.

2017, Lindlar, Michelle, Tunnat, Yvonne, Wilson, Carl

Digital preservation and active software stewardship are both cyclical processes. While digital preservation strategies have to be reevaluated regularly to ensure that they still meet technological and organizational requirements, software needs to be tested with every new release to ensure that it functions correctly. JHOVE is an open source format validation tool which plays a central role in many digital preservation workflows and the PDF module is one of its most important features. Unlike tools such as Adobe PreFlight or veraPDF which check against requirements at profile level, JHOVE’s PDF-module is the only tool that can validate the syntax and structure of PDF files. Despite JHOVE’s widespread and long-standing adoption, the underlying validation rules are not formally or thoroughly tested, leading to bugs going undetected for a long time. Furthermore, there is no ground-truth data set which can be used to understand and test PDF validation at the structural level. The authors present a corpus of light-weight files designed to test the validation criteria of JHOVE’s PDF module against “well-formedness”. We conclude by measuring the code coverage of the test corpus within JHOVE PDF validation and by feeding detected inconsistencies of the PDF-module back into the open source development process.

2017, Piniewski, Mikołaj, Meresa, Hadush Kidane, Romanowicz, Renata, Osuch, Marzena, Szczes´niak, Mateusz, Kardel, Ignacy, Okruszko, Tomasz, Mezghani, Abdelkader, Kundzewicz, Zbigniew W.

River flow projections for two future time horizons and RCP 8.5 scenario, generated by two projects (CHASE-PL and CHIHE) in the Polish-Norwegian Research Programme, were compared. The projects employed different hydrological models over different spatial domains. The semi-distributed, process-based, SWAT model was used in the CHASE-PL project for the entire Vistula and Odra basins area, whilst the lumped, conceptual, HBV model was used in the CHIHE project for eight Polish catchments, for which the comparison study was made. Climate projections in both studies originated from the common EURO-CORDEX dataset, but they were different, e.g. due to different bias correction approaches. Increases in mean annual and seasonal flows were projected in both studies, yet the magnitudes of changes were largely different, in particular for the lowland catchments in the far future. The HBV-based increases were significantly higher in the latter case than the SWAT-based increases in all seasons except winter. Uncertainty in projections is high and creates a problem for practitioners.

2017, Henning, Christian, Ewerth, Ralph

Photos, drawings, figures, etc. supplement textual information in various kinds of media, for example, in web news or scientific pub- lications. In this respect, the intended effect of an image can be quite different, e.g., providing additional information, focusing on certain details of surrounding text, or simply being a general il- lustration of a topic. As a consequence, the semantic correlation between information of different modalities can vary noticeably, too. Moreover, cross-modal interrelations are often hard to describe in a precise way. The variety of possible interrelations of textual and graphical information and the question, how they can be de- scribed and automatically estimated have not been addressed yet by previous work. In this paper, we present several contributions to close this gap. First, we introduce two measures to describe cross- modal interrelations: cross-modal mutual information (CMI) and semantic correlation (SC). Second, a novel approach relying on deep learning is suggested to estimate CMI and SC of textual and visual information. Third, three diverse datasets are leveraged to learn an appropriate deep neural network model for the demanding task. The system has been evaluated on a challenging test set and the experimental results demonstrate the feasibility of the approach.

2017, Michel, Eric, Belkacem, Kevin, Samadi, Reza, de Assis Peralta, Raphael, Renié, Christian, Abed, Mahfoudh, Lin, Guangyuan, Christensen-Dalsgaard, Jørgen, Houdek, Günter, Handberg, Rasmus, Gizon, Laurent, Burston, Raymond, Nagashima, Kaori, Pallé, Pere, Poretti, Ennio, Rainer, Monica, Mistò, Angelo, Panzera, Maria Rosa, Roth, Markus, Monteiro, Mário J. P. F. G., Cunha, Margarida S., Ferreira, João Miguel T. S.

The growing amount of seismic data available from space missions (SOHO, CoRoT, Kepler, SDO,…) but also from ground-based facilities (GONG, BiSON, ground-based large programmes…), stellar modelling and numerical simulations, creates new scientific perspectives such as characterizing stellar populations in our Galaxy or planetary systems by providing model-independent global properties of stars such as mass, radius, and surface gravity within several percent accuracy, as well as constraints on the age. These applications address a broad scientific community beyond the solar and stellar one and require combining indices elaborated with data from different databases (e.g. seismic archives and ground-based spectroscopic surveys). It is thus a basic requirement to develop a simple and effcient access to these various data resources and dedicated tools. In the framework of the European project SpaceInn (FP7), several data sources have been developed or upgraded. The Seismic Plus Portal has been developed, where synthetic descriptions of the most relevant existing data sources can be found, as well as tools allowing to localize existing data for given objects or period and helping the data query. This project has been developed within the Virtual Observatory (VO) framework. In this paper, we give a review of the various facilities and tools developed within this programme. The SpaceInn project (Exploitation of Space Data for Innovative Helio- and Asteroseismology) has been initiated by the European Helio- and Asteroseismology Network (HELAS).

2017, Liu, Kai, Ma, Chao, Göstl, Robert, Zhang, Lei, Herrmann, Andreas

ConspectusBiomacromolecules, such as nucleic acids, proteins, and virus particles, are persistent molecular entities with dimensions that exceed the range of their intermolecular forces hence undergoing degradation by thermally induced bond-scission upon heating. Consequently, for this type of molecule, the absence of a liquid phase can be regarded as a general phenomenon. However, certain advantageous properties usually associated with the liquid state of matter, such as processability, flowability, or molecular mobility, are highly sought-after features for biomacromolecules in a solvent-free environment. Here, we provide an overview over the design principles and synthetic pathways to obtain solvent-free liquids of biomacromolecular architectures approaching the topic from our own perspective of research. We will highlight the milestones in synthesis, including a recently developed general surfactant complexation method applicable to a large variety of biomacromolecules as well as other synthetic principles granting access to electrostatically complexed proteins and DNA.These synthetic pathways retain the function and structure of the biomacromolecules even under extreme, nonphysiological conditions at high temperatures in water-free melts challenging the existing paradigm on the role of hydration in structural biology. Under these conditions, the resulting complexes reveal their true potential for previously unthinkable applications. Moreover, these protocols open a pathway toward the assembly of anisotropic architectures, enabling the formation of solvent-free biomacromolecular thermotropic liquid crystals. These ordered biomaterials exhibit vastly different mechanical properties when compared to the individual building blocks. Beyond the preparative aspects, we will shine light on the unique potential applications and technologies resulting from solvent-free biomacromolecular fluids: From charge transport in dehydrated liquids to DNA electrochromism to biocatalysis in the absence of a protein hydration shell. Moreover, solvent-free biological liquids containing viruses can be used as novel storage and process media serving as a formulation technology for the delivery of highly concentrated bioactive compounds. We are confident that this new class of hybrid biomaterials will fuel further studies and applications of biomacromolecules beyond water and other solvents and in a much broader context than just the traditional physiological conditions. © 2017 American Chemical Society.

2017, Tobschall, Esther

Auch nach 25 Jahren ist der E-Print-Server arXiv noch immer eine bedeutende Plattform für die schnelle Veröffentlichung von Forschungsergebnissen und we-sentliche Informationsquelle für seine Fachgebiete. arXiv ist zentrales Fachrepo-sitorium und gilt als Prototyp des Open-Access-Publizierens. Dennoch hat Erfolg auch immer seinen Preis: Dieser Beitrag stellt die Informationsplattform arXiv vor und beschreibt die Erfahrungen mit einem Geschäftsmodell, das über Mit-gliedsbeiträge eine nachhaltige Finanzierung erreichen will.

2017, Heck, Tamara, Blümel, Ina, Heller, Lambert, Mazarakis, Athanasios, Peters, Isabella, Scherp, Ansgar, Weisel, Luzian

Based on a checklist that was developed during a workshop at OER Camp 2016 and presented as a Science 2.0 conference 2016 poster [1], we conducted an online survey among university teachers representing a sufficient variety of subjects. The survey was online from Feb 6th to March 3rd 2017. We got 360 responses, whereof 210 were completes, see raw data [2]. The poster is presented at Open Science Conference, 21.-22.3.2017, Berlin.