@misc{EichSchmaelzlinLoehmannsroeben2013, author = {Eich, Susanne and Schm{\"a}lzlin, Elmar and L{\"o}hmannsr{\"o}ben, Hans-Gerd}, title = {Distributed fiber optical sensing of oxygen with optical time domain reflectometry}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1085}, issn = {1866-8372}, doi = {10.25932/publishup-47665}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-476659}, pages = {16}, year = {2013}, abstract = {In many biological and environmental applications spatially resolved sensing of molecular oxygen is desirable. A powerful tool for distributed measurements is optical time domain reflectometry (OTDR) which is often used in the field of telecommunications. We combine this technique with a novel optical oxygen sensor dye, triangular-[4] phenylene (TP), immobilized in a polymer matrix. The TP luminescence decay time is 86 ns. The short decay time of the sensor dye is suitable to achieve a spatial resolution of some meters. In this paper we present the development and characterization of a reflectometer in the UV range of the electromagnetic spectrum as well as optical oxygen sensing with different fiber arrangements.}, language = {en} } @misc{BuschingKrahe2013, author = {Busching, Robert and Krah{\´e}, Barbara}, title = {Charging neutral cues with aggressive meaning through violent video game play}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {678}, issn = {1866-8364}, doi = {10.25932/publishup-47618}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-476181}, pages = {14}, year = {2013}, abstract = {When playing violent video games, aggressive actions are performed against the background of an originally neutral environment, and associations are formed between cues related to violence and contextual features. This experiment examined the hypothesis that neutral contextual features of a virtual environment become associated with aggressive meaning and acquire the function of primes for aggressive cognitions. Seventy-six participants were assigned to one of two violent video game conditions that varied in context (ship vs. city environment) or a control condition. Afterwards, they completed a Lexical Decision Task to measure the accessibility of aggressive cognitions in which they were primed either with ship-related or city-related words. As predicted, participants who had played the violent game in the ship environment had shorter reaction times for aggressive words following the ship primes than the city primes, whereas participants in the city condition responded faster to the aggressive words following the city primes compared to the ship primes. No parallel effect was observed for the non-aggressive targets. The findings indicate that the associations between violent and neutral cognitions learned during violent game play facilitate the accessibility of aggressive cognitions.}, language = {en} } @misc{WessigMatthes2013, author = {Wessig, Pablo and Matthes, Annika}, title = {Photochemical synthesis and properties of 1,6- and 1,8-Naphthalenophanes}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1042}, issn = {1866-8372}, doi = {10.25932/publishup-47667}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-476675}, pages = {13}, year = {2013}, abstract = {Various 1,6- and 1,8-naphthalenophanes were synthesized by using the Photo-Dehydro-Diels-Alder (PDDA) reaction of bis-ynones. These compounds are easily accessible from omega-(3-iodophenyl)carboxylic acids in three steps. The obtained naphthalenophanes are axially chiral and the activation barrier for the atropisomerization could be determined in some cases by means of dynamic NMR (DNMR) and/or dynamic HPLC (DHPLC) experiments.}, language = {en} } @misc{BaumannArndtMueller2013, author = {Baumann, Tobias and Arndt, Katja Maren and M{\"u}ller, Kristian M.}, title = {Directional cloning of DNA fragments using deoxyinosine-containing oligonucleotides and endonuclease V}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {983}, issn = {1866-8372}, doi = {10.25932/publishup-43108}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-431085}, pages = {13}, year = {2013}, abstract = {Background: DNA fragments carrying internal recognition sites for the restriction endonucleases intended for cloning into a target plasmid pose a challenge for conventional cloning. Results: A method for directional insertion of DNA fragments into plasmid vectors has been developed. The target sequence is amplified from a template DNA sample by PCR using two oligonucleotides each containing a single deoxyinosine base at the third position from the 5' end. Treatment of such PCR products with endonuclease V generates 3' protruding ends suitable for ligation with vector fragments created by conventional restriction endonuclease reactions. Conclusions: The developed approach generates terminal cohesive ends without the use of Type II restriction endonucleases, and is thus independent from the DNA sequence. Due to PCR amplification, minimal amounts of template DNA are required. Using the robust Taq enzyme or a proofreading Pfu DNA polymerase mutant, the method is applicable to a broad range of insert sequences. Appropriate primer design enables direct incorporation of terminal DNA sequence modifications such as tag addition, insertions, deletions and mutations into the cloning strategy. Further, the restriction sites of the target plasmid can be either retained or removed.}, language = {en} } @misc{ZaourarHamoudiMandeaetal.2013, author = {Zaourar, Naima and Hamoudi, Mohamed and Mandea, Mioara and Balasis, Georgios and Holschneider, Matthias}, title = {Wavelet-based multiscale analysis of geomagnetic disturbance}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, volume = {65}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {12}, issn = {1866-8372}, doi = {10.25932/publishup-43691}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-436912}, pages = {1525 -- 1540}, year = {2013}, abstract = {The dynamics of external contributions to the geomagnetic field is investigated by applying time-frequency methods to magnetic observatory data. Fractal models and multiscale analysis enable obtaining maximum quantitative information related to the short-term dynamics of the geomagnetic field activity. The stochastic properties of the horizontal component of the transient external field are determined by searching for scaling laws in the power spectra. The spectrum fits a power law with a scaling exponent β, a typical characteristic of self-affine time-series. Local variations in the power-law exponent are investigated by applying wavelet analysis to the same time-series. These analyses highlight the self-affine properties of geomagnetic perturbations and their persistence. Moreover, they show that the main phases of sudden storm disturbances are uniquely characterized by a scaling exponent varying between 1 and 3, possibly related to the energy contained in the external field. These new findings suggest the existence of a long-range dependence, the scaling exponent being an efficient indicator of geomagnetic activity and singularity detection. These results show that by using magnetogram regularity to reflect the magnetosphere activity, a theoretical analysis of the external geomagnetic field based on local power-law exponents is possible.}, language = {en} } @misc{KarpuzCevikKoppitzetal.2013, author = {Karpuz, Eylem Guzel and {\c{C}}evik, Ahmet Sinan and Koppitz, J{\"o}rg and Cangul, Ismail Naci}, title = {Some fixed-point results on (generalized) Bruck-Reilly ∗-extensions of monoids}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {942}, issn = {1866-8372}, doi = {10.25932/publishup-43270}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-432701}, pages = {11}, year = {2013}, abstract = {In this paper, we determine necessary and sufficient conditions for Bruck-Reilly and generalized Bruck-Reilly ∗-extensions of arbitrary monoids to be regular, coregular and strongly π-inverse. These semigroup classes have applications in various field of mathematics, such as matrix theory, discrete mathematics and p-adic analysis (especially in operator theory). In addition, while regularity and coregularity have so many applications in the meaning of boundaries (again in operator theory), inverse monoids and Bruck-Reilly extensions contain a mixture fixed-point results of algebra, topology and geometry within the purposes of this journal.}, language = {en} } @misc{BenteleSaffertRauscheretal.2013, author = {Bentele, Kajetan and Saffert, Paul and Rauscher, Robert and Ignatova, Zoya and Bluethgen, Nils}, title = {Efficient translation initiation dictates codon usage at gene start}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {912}, issn = {1866-8372}, doi = {10.25932/publishup-44133}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-441337}, pages = {12}, year = {2013}, abstract = {The genetic code is degenerate; thus, protein evolution does not uniquely determine the coding sequence. One of the puzzles in evolutionary genetics is therefore to uncover evolutionary driving forces that result in specific codon choice. In many bacteria, the first 5-10 codons of protein-coding genes are often codons that are less frequently used in the rest of the genome, an effect that has been argued to arise from selection for slowed early elongation to reduce ribosome traffic jams. However, genome analysis across many species has demonstrated that the region shows reduced mRNA folding consistent with pressure for efficient translation initiation. This raises the possibility that unusual codon usage is a side effect of selection for reduced mRNA structure. Here we discriminate between these two competing hypotheses, and show that in bacteria selection favours codons that reduce mRNA folding around the translation start, regardless of whether these codons are frequent or rare. Experiments confirm that primarily mRNA structure, and not codon usage, at the beginning of genes determines the translation rate.}, language = {en} } @misc{VanBelProostVanNesteetal.2013, author = {Van Bel, Michiel and Proost, Sebastian and Van Neste, Christophe and Deforce, Dieter and Van de Peer, Yves and Vandepoele, Klaas}, title = {TRAPID}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {900}, issn = {1866-8372}, doi = {10.25932/publishup-43640}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-436409}, pages = {12}, year = {2013}, abstract = {Transcriptome analysis through next-generation sequencing technologies allows the generation of detailed gene catalogs for non-model species, at the cost of new challenges with regards to computational requirements and bioinformatics expertise. Here, we present TRAPID, an online tool for the fast and efficient processing of assembled RNA-Seq transcriptome data, developed to mitigate these challenges. TRAPID offers high-throughput open reading frame detection, frameshift correction and includes a functional, comparative and phylogenetic toolbox, making use of 175 reference proteomes. Benchmarking and comparison against state-of-the-art transcript analysis tools reveals the efficiency and unique features of the TRAPID system. TRAPID is freely available at http://bioinformatics.psb.ugent.be/webtools/trapid/.}, language = {en} } @misc{HerrmannKritikos2013, author = {Herrmann, Benedikt and Kritikos, Alexander}, title = {Growing out of the crisis}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {896}, issn = {1866-8372}, doi = {10.25932/publishup-43480}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-434805}, pages = {25}, year = {2013}, abstract = {Greece's currently planned institutional reforms will help to get the country going with limited economic growth. With an economy based primarily on tourism, trade, and agriculture, Greece lacks an established competitive industry and an innovation-friendly environment, resulting in a low export ratio given the small size of the country and its long-time EU-membership. Instead, Greece exports only its nation's talent, with low returns. To become prosperous, the country must better capitalize on its Eurozone membership and add innovative sectors to its economic structure. Given Greece's hidden assets, such as the attractiveness of the country, a small number of strong research centers and an impressive diaspora in research, finance and business, we envision a Greek "Silicon Valley" and propose a ten point policy plan to achieve that goal.}, language = {en} } @misc{MolahajlooPirhayati2013, author = {Molahajloo, Shahla and Pirhayati, Mohammad}, title = {Traces of pseudo-differential operators on compact and Hausdorff groups}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe}, number = {893}, issn = {1866-8372}, doi = {10.25932/publishup-43637}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-436371}, pages = {361 -- 369}, year = {2013}, abstract = {We give a characterization of and a trace formula for trace class pseudo-differential operators on compact Hausdorff groups.}, language = {en} } @misc{ThomasMatuschekGrima2013, author = {Thomas, Philipp and Matuschek, Hannes and Grima, Ramon}, title = {How reliable is the linear noise approximation of gene regulatory networks?}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe}, number = {876}, issn = {1866-8372}, doi = {10.25932/publishup-43502}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-435028}, pages = {17}, year = {2013}, abstract = {Background: The linear noise approximation (LNA) is commonly used to predict how noise is regulated and exploited at the cellular level. These predictions are exact for reaction networks composed exclusively of first order reactions or for networks involving bimolecular reactions and large numbers of molecules. It is however well known that gene regulation involves bimolecular interactions with molecule numbers as small as a single copy of a particular gene. It is therefore questionable how reliable are the LNA predictions for these systems. Results: We implement in the software package intrinsic Noise Analyzer (iNA), a system size expansion based method which calculates the mean concentrations and the variances of the fluctuations to an order of accuracy higher than the LNA. We then use iNA to explore the parametric dependence of the Fano factors and of the coefficients of variation of the mRNA and protein fluctuations in models of genetic networks involving nonlinear protein degradation, post-transcriptional, post-translational and negative feedback regulation. We find that the LNA can significantly underestimate the amplitude and period of noise-induced oscillations in genetic oscillators. We also identify cases where the LNA predicts that noise levels can be optimized by tuning a bimolecular rate constant whereas our method shows that no such regulation is possible. All our results are confirmed by stochastic simulations. Conclusion: The software iNA allows the investigation of parameter regimes where the LNA fares well and where it does not. We have shown that the parametric dependence of the coefficients of variation and Fano factors for common gene regulatory networks is better described by including terms of higher order than LNA in the system size expansion. This analysis is considerably faster than stochastic simulations due to the extensive ensemble averaging needed to obtain statistically meaningful results. Hence iNA is well suited for performing computationally efficient and quantitative studies of intrinsic noise in gene regulatory networks.}, language = {en} } @misc{GrubmuellerGoetschKrieger2013, author = {Grubm{\"u}ller, Verena and G{\"o}tsch, Katharina and Krieger, Bernhard}, title = {Social media analytics for future oriented policy making}, series = {Postprints der Universit{\"a}t Potsdam : Wirtschafts- und Sozialwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Wirtschafts- und Sozialwissenschaftliche Reihe}, number = {121}, issn = {1867-5808}, doi = {10.25932/publishup-43200}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-432007}, pages = {11}, year = {2013}, abstract = {Research indicates that evidence-based policy making is most successful when public administrators refer to diversified information portfolios. With the rising prominence of social media in the last decade, this paper argues that governments can benefit from integrating this publically available, user-generated data through the technique of social media analytics (SMA). There are already several initiatives set up to predict future policy issues, e.g. for the policy fields of crisis mitigation or migrant integration insights. The authors analyse these endeavours and their potential for providing more efficient and effective public policies. Furthermore, they scrutinise the challenges to governmental SMA usage in particular with regards to legal and ethical aspects. Reflecting the latter, this paper provides forward-looking recommendations on how these technologies can best be used for future policy making in a legally and ethically sound manner.}, language = {en} } @misc{GschwindKressigLacroixetal.2013, author = {Gschwind, Yves J. and Kressig, Reto W. and Lacroix, Andre and M{\"u}hlbauer, Thomas and Pfenninger, Barbara and Granacher, Urs}, title = {A best practice fall prevention exercise program to improve balance, strength/power, and psychosocial health in older adults}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {604}, issn = {1866-8364}, doi = {10.25932/publishup-42710}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-427104}, pages = {15}, year = {2013}, abstract = {Background: With increasing age neuromuscular deficits (e.g., sarcopenia) may result in impaired physical performance and an increased risk for falls. Prominent intrinsic fall-risk factors are age-related decreases in balance and strength / power performance as well as cognitive decline. Additional studies are needed to develop specifically tailored exercise programs for older adults that can easily be implemented into clinical practice. Thus, the objective of the present trial is to assess the effects of a fall prevention program that was developed by an interdisciplinary expert panel on measures of balance, strength / power, body composition, cognition, psychosocial well-being, and falls self-efficacy in healthy older adults. Additionally, the time-related effects of detraining are tested. Methods/Design: Healthy old people (n = 54) between the age of 65 to 80 years will participate in this trial. The testing protocol comprises tests for the assessment of static / dynamic steady-state balance (i.e., Sharpened Romberg Test, instrumented gait analysis), proactive balance (i.e., Functional Reach Test; Timed Up and Go Test), reactive balance (i.e., perturbation test during bipedal stance; Push and Release Test), strength (i.e., hand grip strength test; Chair Stand Test), and power (i.e., Stair Climb Power Test; countermovement jump). Further, body composition will be analysed using a bioelectrical impedance analysis system. In addition, questionnaires for the assessment of psychosocial (i.e., World Health Organisation Quality of Life Assessment-Bref), cognitive (i.e., Mini Mental State Examination), and fall risk determinants (i.e., Fall Efficacy Scale -International) will be included in the study protocol. Participants will be randomized into two intervention groups or the control / waiting group. After baseline measures, participants in the intervention groups will conduct a 12-week balance and strength / power exercise intervention 3 times per week, with each training session lasting 30 min. (actual training time). One intervention group will complete an extensive supervised training program, while the other intervention group will complete a short version (` 3 times 3') that is home-based and controlled by weekly phone calls. Post-tests will be conducted right after the intervention period. Additionally, detraining effects will be measured 12 weeks after program cessation. The control group / waiting group will not participate in any specific intervention during the experimental period, but will receive the extensive supervised program after the experimental period. Discussion: It is expected that particularly the supervised combination of balance and strength / power training will improve performance in variables of balance, strength / power, body composition, cognitive function, psychosocial well-being, and falls self-efficacy of older adults. In addition, information regarding fall risk assessment, dose-response-relations, detraining effects, and supervision of training will be provided. Further, training-induced health-relevant changes, such as improved performance in activities of daily living, cognitive function, and quality of life, as well as a reduced risk for falls may help to lower costs in the health care system. Finally, practitioners, therapists, and instructors will be provided with a scientifically evaluated feasible, safe, and easy-to-administer exercise program for fall prevention.}, language = {en} } @misc{DemskeSuetterlinRostetal.2013, author = {Demske, Ulrike and S{\"u}tterlin, Sabine and Rost, Sophia and Zimmermann, Matthias and Kampe, Heike and Eckardt, Barbara and Horn-Conrad, Antje}, title = {Portal Wissen = Borders}, number = {02/2013}, organization = {University of Potsdam, Press and Public Relations Department}, issn = {2198-9974}, doi = {10.25932/publishup-44143}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-441430}, pages = {55}, year = {2013}, abstract = {The new edition of the Potsdam Research Magazine "Portal Wissen" approaches the subject "Borders" from different perspectives. As a linguist, this headline makes me think of linguistic borders and the effects that might result from the contact of two languages at a particular border. There is, for instance, ample evidence of code-switching, i.e. the use of material from at least two languages in a single utterance. The reasons for code-switching can be manifold. On the one hand, code-switching may result from a limited language competence, for example if a speaker lacks a particular word in a nonnative language. On the other hand, code-switching may be a matter of prestige if the speaker wants to demonstrate his or her affiliation to a certain social group by switching languages. If code-switching does not only occur sporadically but involves whole language communities over a longer period of time, it can result in significant changes of the involved languages. Which language "gives" and which one "takes" is determined by sociolinguistic factors. It is, hence, quite easy to predict that German varieties spoken in language islands in South and Eastern Europe as well as in North and Latin America will absorb more and more language material from their neighbouring languages until they disappear unless political will strives to preserve these language varieties. Increasing mobility of modern societies has multiplied the extent and the intensity of language contact and certainly comprises a large number of different contact situations besides the one most commonly known, i.e. the contact between German and English. From a historic point of view, German witnesses a strong influence of various Romance languages such as Latin, French and Italian. In Potsdam, one cannot help being reminded of the French influence during the 18th century. Overcoming language borders becomes also apparent in the everyday life of an international research university. In March this year, the Annual Conference of the German Linguistic Society took place in Potsdam, with more than 500 participants. Lingua franca of this conference was English. Compared to previous conferences, this further increased the number of international participants. The articles in this edition illustrate various approaches to the topic "Borders": On the trail of "Boundary Surveys", we follow the Australian explorer Ludwig Leichhardt. "Travellers Across Borders" is focussed on articles dealing with the literature of the colonial Caribbean or with the work of an Italian geologist deep beneath the earth's surface, for example. Looking for the "Boundless", our authors follow scientists who discuss questions like "Why love hurts?". The present issue of "Portal Wissen" also takes into account "Drawing Up Borders" in an article that is concerned with the limits of workrelated stress. Instances of successful "Border Crossing" are provided by the "Handkerchief Lab" as well as by new biotechnological applications. I would like to wish you inspiring border experiences, hoping that you will get many impulses for crossing professional borders in your field of expertise. Prof. Ulrike Demske Professor of the History and the Varieties of the German Language Vice President International Affairs, Alumni and Fundraising}, language = {en} } @misc{StreckerKampeSuetterlinetal.2013, author = {Strecker, Manfred and Kampe, Heike and S{\"u}tterlin, Sabine and Horn-Conrad, Antje and Zimmermann, Matthias and Eckardt, Barbara and G{\"o}rlich, Petra}, title = {Portal Wissen = Layers}, number = {01/2013}, organization = {University of Potsdam, Press and Public Relations Department}, issn = {2198-9974}, doi = {10.25932/publishup-44140}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-441404}, pages = {53}, year = {2013}, abstract = {The latest edition of our Potsdam Research Magazine "Portal Wissen" addresses the topic "Layers" in many different ways. Geoscientists often deal with layers: layers of soil, sediment, or rock are the evidence of repeated and long-lasting processes of erosion and sedimentation that took place in the early history of the earth. For instance, mountains are eroded by water, ice and wind. The sand that results from that erosion might eventually form a new layer on the ocean floor known as a sediment horizon. After tens of millions of years, tectonic plate movements can deform the ocean floor, pushing it upwards as mountains are created, bringing the layers of sand from former mountain chains together with fossilized sea dwellers into the realm of climbers and mountaineers - a fundamental cycle within the Earth system that was succinctly described by Ibn Sina nearly 1000 years ago, and later by Charles Darwin when he was crossing the Andes. The landscape around us overlays the products of recent processes with those from the past. Slow processes or extreme events that happen very rarely - like floods, earthquakes or rockslides - wipe out certain characteristics, while others remain on the surface. In this sense, the landscape is like a palimpsest - a piece of parchment that monks in the Middle Ages scraped clean again and again to write something new. Analysing rock layers and soil is similar to the work of a detective. Geophysical deep sounding with sound and radar waves, precise measurements of motions related to earthquakes, and deep boreholes each provide a glimpse of the characteristics of what lies beneath us, giving us a better understanding of spatial distribution of the various layers. Fossils can tell us the age of a layer of sediment, while radiometric isotopes in minerals reveal how quickly a rock moved from deep within the Earth up to the surface, perhaps during the process of mountain building. Thin layers of ash tell us when there was a devastating volcanic eruption that influenced environmental conditions. The shape, gradation, and surface conditions of sand grains reflect whether wind or water was responsible for their transport. We know, for instance, that northern Germany was a desert landscape more than 260 million years ago. At that time, the wind made huge dunes migrate across the region. Over time, climate and vegetation slowly alter the physical and chemical characteristics of sand and rock at the surface, turning them into soil, the epidermis of our planet. Mineralogical analyses of layers of the soil layer tell us whether the climate was dry or wet. These kinds of observations allow us to reconstruct links between our climate system and processes that have taken place on the Earth's surface, as well as those processes that originate at much deeper levels. The clues we use might be hidden under the surface of the earth or clearly visible on the surface, like in the mountains, or even in freshly cut rock alongside roads. On the following pages, we invite you to accompany scientists from Potsdam into their world of research. They track hidden traces of longgone earthquakes in the Tien Shan Mountains; they discover ancient forms of life in deep-sea sediments. They even examine layers in outer space that can tell us something about the formation of planets. "Portal Wissen" not only presents scientists of the University of Potsdam who deal with the sequence of layers formed by solid rock, but also those scientists who deal with levels of education or social strata. Research scientists explain how to implement the social mission of inclusion in teaching, and how pupils from the Berlin district Kreuzberg examine language in urban neighbourhoods together with students from the University of Potsdam. Although these types of "layers" are very different, they all have something in common. Their structure and profile are evidence of continuously changing conditions. The present will leave traces and layers that future geoscientists will measure and examine. We already speak of the Anthropocene, a geological era dominated by humans, which is characterized by far-reaching changes in erosion and sedimentation rates, and the displacement of natural habitats. I hope that you will discover exciting and inspiring stories in this edition. And remember - it is always worth having a look beneath the surface. Prof. Manfred Strecker, PHD Professor of Geology}, language = {en} } @misc{BoldtLeberBonaventuraetal.2013, author = {Boldt, Julia and Leber, Alexander W. and Bonaventura, Klaus and Sohns, Christian and Stula, Martin and Huppertz, Alexander and Haverkamp, Wilhelm and Dorenkamp, Marc}, title = {Cost-effectiveness of cardiovascular magnetic resonance and single-photon emission computed tomography for diagnosis of coronary artery disease in Germany}, series = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe}, number = {551}, issn = {1866-8364}, doi = {10.25932/publishup-43010}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-430107}, pages = {11}, year = {2013}, abstract = {Background: Recent studies have demonstrated a superior diagnostic accuracy of cardiovascular magnetic resonance (CMR) for the detection of coronary artery disease (CAD). We aimed to determine the comparative cost-effectiveness of CMR versus single-photon emission computed tomography (SPECT). Methods: Based on Bayes' theorem, a mathematical model was developed to compare the cost-effectiveness and utility of CMR with SPECT in patients with suspected CAD. Invasive coronary angiography served as the standard of reference. Effectiveness was defined as the accurate detection of CAD, and utility as the number of quality-adjusted life-years (QALYs) gained. Model input parameters were derived from the literature, and the cost analysis was conducted from a German health care payer's perspective. Extensive sensitivity analyses were performed. Results: Reimbursement fees represented only a minor fraction of the total costs incurred by a diagnostic strategy. Increases in the prevalence of CAD were generally associated with improved cost-effectiveness and decreased costs per utility unit (Delta QALY). By comparison, CMR was consistently more cost-effective than SPECT, and showed lower costs per QALY gained. Given a CAD prevalence of 0.50, CMR was associated with total costs of (sic)6,120 for one patient correctly diagnosed as having CAD and with (sic)2,246 per Delta QALY gained versus (sic)7,065 and (sic)2,931 for SPECT, respectively. Above a threshold value of CAD prevalence of 0.60, proceeding directly to invasive angiography was the most cost-effective approach. Conclusions: In patients with low to intermediate CAD probabilities, CMR is more cost-effective than SPECT. Moreover, lower costs per utility unit indicate a superior clinical utility of CMR.}, language = {en} } @misc{GoychukKharchenko2013, author = {Goychuk, Igor and Kharchenko, Vasyl O.}, title = {Rocking subdiffusive ratchets}, series = {Mathematical Modelling of Natural Phenomena}, journal = {Mathematical Modelling of Natural Phenomena}, number = {622}, issn = {1866-8372}, doi = {10.1051/mmnp/20138210}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-416138}, pages = {15}, year = {2013}, abstract = {We study origin, parameter optimization, and thermodynamic efficiency of isothermal rocking ratchets based on fractional subdiffusion within a generalized non-Markovian Langevin equation approach. A corresponding multi-dimensional Markovian embedding dynamics is realized using a set of auxiliary Brownian particles elastically coupled to the central Brownian particle (see video on the journal web site). We show that anomalous subdiffusive transport emerges due to an interplay of nonlinear response and viscoelastic effects for fractional Brownian motion in periodic potentials with broken space-inversion symmetry and driven by a time-periodic field. The anomalous transport becomes optimal for a subthreshold driving when the driving period matches a characteristic time scale of interwell transitions. It can also be optimized by varying temperature, amplitude of periodic potential and driving strength. The useful work done against a load shows a parabolic dependence on the load strength. It grows sublinearly with time and the corresponding thermodynamic efficiency decays algebraically in time because the energy supplied by the driving field scales with time linearly. However, it compares well with the efficiency of normal diffusion rocking ratchets on an appreciably long time scale.}, language = {en} } @misc{DrielGesztelyiBakerToeroeketal.2013, author = {Driel-Gesztelyi, L. van and Baker, Daniel N. and T{\"o}r{\"o}k, Tibor and Pariat, Etienne and Green, L. M. and Williams, D. R. and Carlyle, J. and Valori, G. and D{\´e}moulin, Pascal and Matthews, S. A. and Kliem, Bernhard and Malherbe, J.-M.}, title = {Magnetic reconnection driven by filament eruption in the 7 June 2011 event}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch Naturwissenschaftliche Reihe}, number = {608}, doi = {10.25932/publishup-41567}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-415671}, pages = {502 -- 503}, year = {2013}, abstract = {During an unusually massive filament eruption on 7 June 2011, SDO/AIA imaged for the first time significant EUV emission around a magnetic reconnection region in the solar corona. The reconnection occurred between magnetic fields of the laterally expanding CME and a neighbouring active region. A pre-existing quasi-separatrix layer was activated in the process. This scenario is supported by data-constrained numerical simulations of the eruption. Observations show that dense cool filament plasma was re-directed and heated in situ, producing coronal-temperature emission around the reconnection region. These results provide the first direct observational evidence, supported by MHD simulations and magnetic modelling, that a large-scale re-configuration of the coronal magnetic field takes place during solar eruptions via the process of magnetic reconnection.}, language = {en} } @misc{GreenKliem2013, author = {Green, Lucie M. and Kliem, Bernhard}, title = {Observations of flux rope formation prior to coronal mass ejections}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {607}, issn = {1866-8372}, doi = {10.25932/publishup-41610}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-416103}, pages = {6}, year = {2013}, abstract = {Understanding the magnetic configuration of the source regions of coronal mass ejections (CMEs) is vital in order to determine the trigger and driver of these events. Observations of four CME productive active regions are presented here, which indicate that the pre-eruption magnetic configuration is that of a magnetic flux rope. The flux ropes are formed in the solar atmosphere by the process known as flux cancellation and are stable for several hours before the eruption. The observations also indicate that the magnetic structure that erupts is not the entire flux rope as initially formed, raising the question of whether the flux rope is able to undergo a partial eruption or whether it undergoes a transition in specific flux rope configuration shortly before the CME.}, language = {en} } @misc{SchatzOhlendorfBusseetal.2013, author = {Schatz, Juliane and Ohlendorf, Bernd and Busse, Peter and Pelz, Gerrit and Dolch, Dietrich and Teubner, Jens and Encarnacao, Jorge A. and M{\"u}hle, Ralf-Udo and Fischer, M. and Hoffmann, Bernd and Kwasnitschka, Linda and Balkema-Buschmann, Anne and Mettenleiter, Thomas Christoph and M{\"u}ller, T. and Freuling, Conrad M.}, title = {Twenty years of active bat rabies surveillance in Germany}, series = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam Humanwissenschaftliche Reihe}, number = {533}, issn = {1866-8364}, doi = {10.25932/publishup-41514}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-415140}, pages = {12}, year = {2013}, abstract = {In Germany, active bat rabies surveillance was conducted between 1993 and 2012. A total of 4546 oropharyngeal swab samples from 18 bat species were screened for the presence of EBLV-1- , EBLV-2- and BBLV-specific RNA. Overall, 0 center dot 15\% of oropharyngeal swab samples tested EBLV-1 positive, with the majority originating from Eptesicus serotinus. Interestingly, out of seven RT-PCR-positive oropharyngeal swabs subjected to virus isolation, viable virus was isolated from a single serotine bat (E. serotinus). Additionally, about 1226 blood samples were tested serologically, and varying virus neutralizing antibody titres were found in at least eight different bat species. The detection of viral RNA and seroconversion in repeatedly sampled serotine bats indicates long-term circulation of the virus in a particular bat colony. The limitations of random-based active bat rabies surveillance over passive bat rabies surveillance and its possible application of targeted approaches for future research activities on bat lyssavirus dynamics and maintenance are discussed.}, language = {en} }