@article{SmieliauskasBewleyGronewoldetal.2016, author = {Smieliauskas, Wally and Bewley, Kathryn and Gronewold, Ulfert and Menzefricke, Ulrich}, title = {Misleading Forecasts in Accounting Estimates}, series = {Journal of business ethics}, volume = {152}, journal = {Journal of business ethics}, number = {2}, publisher = {Springer}, address = {Dordrecht}, issn = {0167-4544}, doi = {10.1007/s10551-016-3289-1}, pages = {437 -- 457}, year = {2016}, abstract = {The current financial reporting environment, with its increasing use of accounting estimates, including fair value estimates, suggests that unethical accounting estimates may be a growing concern. This paper provides explanations and empirical evidence for why some types of accounting estimates in financial reporting may promote a form of ethical blindness. These types of ethical blindness can have an escalating effect that corrupts not only an individual or organization but also the accounting profession and the public interest it serves. Ethical blindness in the standards of professional accountants may be a factor in the extent of misreporting, and may have taken on new urgency as a result of the proposals to change the conceptual framework for financial reporting using international standards. The social consequences for users of financial statements can be huge. The acquittal of former Nortel executives on fraud charges related to accounting manipulations is viewed by many as legitimizing accounting gamesmanship. This decision illustrates that the courts may not be the best place to deal with ethical reporting issues. The courts may be relied on for only the most egregious unethical conduct and, even then, the accounting profession is ill equipped to assist the legal system in prosecuting accounting fraud unless the standards have been clarified. We argue that the problem of unethical reporting should be addressed by the accounting profession itself, preferably as a key part of the conceptual framework that supports accounting and auditing standards, and the codes of ethical conduct that underpin the professionalism of accountants.}, language = {en} } @article{MoeringLeino2016, author = {M{\"o}ring, Sebastian and Leino, Olli Tapio}, title = {Beyond games as political education}, series = {Journal of Gaming \& Virtual Worlds}, volume = {8}, journal = {Journal of Gaming \& Virtual Worlds}, number = {2}, publisher = {Intellect}, address = {Bristol}, issn = {1757-191X}, doi = {10.1386/jgvw.8.2.145_1}, pages = {145 -- 161}, year = {2016}, abstract = {This article introduces the juxtaposed notions of liberal and neo-liberal gameplay in order to show that, while forms of contemporary game culture are heavily influenced by neo-liberalism, they often appear under a liberal disguise. The argument is grounded in Claus Pias' idea of games as always a product of their time in terms of economic, political and cultural history. The article shows that romantic play theories (e.g. Schiller, Huizinga and Caillois) are circling around the notion of play as 'free', which emerged in parallel with the philosophy of liberalism and respective socio-economic developments such as the industrialization and the rise of the nation state. It shows further that contemporary discourse in computer game studies addresses computer game/play as if it still was the romantic form of play rooted in the paradigm of liberalism. The article holds that an account that acknowledges the neo-liberalist underpinnings of computer games is more suited to addressing contemporary computer games, among which are phenomena such as free to play games, which repeat the structures of a neo-liberal society. In those games the players invest time and effort in developing their skills, although their future value is mainly speculative - just like this is the case for citizens of neo-liberal societies.}, language = {en} } @article{TrautweinFredrikssonMoelleretal.2016, author = {Trautwein, Matthias and Fredriksson, Kai and M{\"o}ller, Heiko Michael and Exner, Thomas E.}, title = {Automated assignment of NMR chemical shifts based on a known structure and 4D spectra}, series = {Journal of biomolecular NMR}, volume = {65}, journal = {Journal of biomolecular NMR}, publisher = {Springer}, address = {Dordrecht}, issn = {0925-2738}, doi = {10.1007/s10858-016-0050-0}, pages = {217 -- 236}, year = {2016}, abstract = {Apart from their central role during 3D structure determination of proteins the backbone chemical shift assignment is the basis for a number of applications, like chemical shift perturbation mapping and studies on the dynamics of proteins. This assignment is not a trivial task even if a 3D protein structure is known and needs almost as much effort as the assignment for structure prediction if performed manually. We present here a new algorithm based solely on 4D [H-1, N-15]-HSQC-NOESY-[H-1, N-15]-HSQC spectra which is able to assign a large percentage of chemical shifts (73-82 \%) unambiguously, demonstrated with proteins up to a size of 250 residues. For the remaining residues, a small number of possible assignments is filtered out. This is done by comparing distances in the 3D structure to restraints obtained from the peak volumes in the 4D spectrum. Using dead-end elimination, assignments are removed in which at least one of the restraints is violated. Including additional information from chemical shift predictions, a complete unambiguous assignment was obtained for Ubiquitin and 95 \% of the residues were correctly assigned in the 251 residue-long N-terminal domain of enzyme I. The program including source code is available at https://github.com/thomasexner/4Dassign.}, language = {en} } @article{MaierPoluektovJesteretal.2016, author = {Maier, Stefan K. and Poluektov, Georgiy and Jester, Stefan-S. and M{\"o}ller, Heiko Michael and Hoeger, Sigurd}, title = {Fast Oxidative Cyclooligomerization towards Low- and High-Symmetry Thiophene Macrocycles}, series = {Chemistry - a European journal}, volume = {22}, journal = {Chemistry - a European journal}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {0947-6539}, doi = {10.1002/chem.201503211}, pages = {1379 -- 1384}, year = {2016}, abstract = {Macrocycles with quaterthiophene subunits were obtained by cyclooligomerization by direct oxidative coupling of unsubstituted dithiophene moieties. The rings were closed with high selectivity by an \&\#945;,\&\#946;\&\#8242;-connection of the thiophenes as proven by NMR spectroscopy. The reaction of the precursor with terthiophene moieties yielded the symmetric \&\#945;,\&\#945;\&\#8242;-linked macrocycle in low yield together with various differently connected isomers. Blocking of the \&\#946;-position of the half-rings yielded selectively the \&\#945;,\&\#945;\&\#8242;-linked macrocycle. Selected cyclothiophenes were investigated by scanning tunneling microscopy, which displayed the formation of highly ordered 2D crystalline monolayers.}, language = {en} } @article{PrestelMoeller2016, author = {Prestel, Andreas and M{\"o}ller, Heiko Michael}, title = {Spatio-temporal control of cellular uptake achieved by photoswitchable cell-penetrating peptides}, series = {Chemical communications}, volume = {52}, journal = {Chemical communications}, publisher = {Royal Society of Chemistry}, address = {Cambridge}, issn = {1359-7345}, doi = {10.1039/c5cc06848g}, pages = {701 -- 704}, year = {2016}, abstract = {The selective uptake of compounds into specific cells of interest is a major objective in cell biology and drug delivery. By incorporation of a novel, thermostable azobenzene moiety we generated peptides that can be switched optically between an inactive state and an active, cell-penetrating state with excellent spatio-temporal control.}, language = {en} } @article{HolertYuecelJagmannetal.2016, author = {Holert, Johannes and Y{\"u}cel, Onur and Jagmann, Nina and Prestel, Andreas and M{\"o}ller, Heiko Michael and Philipp, Bodo}, title = {Identification of bypass reactions leading to the formation of one central steroid degradation intermediate in metabolism of different bile salts in Pseudomonas sp strain Chol1}, series = {Environmental microbiology}, volume = {18}, journal = {Environmental microbiology}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1462-2912}, doi = {10.1111/1462-2920.13192}, pages = {3373 -- 3389}, year = {2016}, language = {en} } @phdthesis{Boehm2016, author = {B{\"o}hm, Ver{\´o}nica Julia}, title = {La imperfectividad en la prensa espa{\~n}ola y su relaci{\´o}n con las categor{\´i}as sem{\´a}nticas de modalidad y evidencialidad}, series = {Potsdam Linguistic Investigations / Potsdamer Linguistische Untersuchungen / Recherches Linguistiques {\`a} Potsdam ; 19}, journal = {Potsdam Linguistic Investigations / Potsdamer Linguistische Untersuchungen / Recherches Linguistiques {\`a} Potsdam ; 19}, publisher = {Lang}, address = {Frankfurt am Main}, isbn = {978-3-631-66776-7}, school = {Universit{\"a}t Potsdam}, pages = {621}, year = {2016}, abstract = {Este libro adopta un enfoque sem{\´a}ntico-funcional en el estudio de la imperfectividad en el espa{\~n}ol. La imperfectividad, como categor{\´i}a sem{\´a}ntico-funcional, encuentra afinidades con otras funciones sem{\´a}nticas, donde el valor de verdad de una situaci{\´o}n se presenta como indeterminado o impreciso como, por ejemplo, en la reproducci{\´o}n de citas y distanciamiento del hablante frente a lo dicho; de manera que la imperfectividad se solapa con la modalidad y evidencialidad. Asimismo, se analizan las funciones secundarias de la imperfectividad relacionadas con la modalidad epist{\´e}mica y evidencialidad indirecta en la prensa espa{\~n}ola. En todos los casos, los textos analizados proceden de corpus reales del espa{\~n}ol (CREA, Corpus del Espa{\~n}ol y GlossaNet).}, language = {es} } @article{StolleMichaelisRauberg2016, author = {Stolle, Claudia and Michaelis, Ingo and Rauberg, Jan}, title = {The role of high-resolution geomagnetic field models for investigating ionospheric currents at low Earth orbit satellites}, series = {Earth, planets and space}, volume = {68}, journal = {Earth, planets and space}, publisher = {Springer}, address = {Heidelberg}, issn = {1880-5981}, doi = {10.1186/s40623-016-0494-1}, pages = {10}, year = {2016}, abstract = {Low Earth orbiting geomagnetic satellite missions, such as the Swarm satellite mission, are the only means to monitor and investigate ionospheric currents on a global scale and to make in situ measurements of F region currents. High-precision geomagnetic satellite missions are also able to detect ionospheric currents during quiet-time geomagnetic conditions that only have few nanotesla amplitudes in the magnetic field. An efficient method to isolate the ionospheric signals from satellite magnetic field measurements has been the use of residuals between the observations and predictions from empirical geomagnetic models for other geomagnetic sources, such as the core and lithospheric field or signals from the quiet-time magnetospheric currents. This study aims at highlighting the importance of high-resolution magnetic field models that are able to predict the lithospheric field and that consider the quiet-time magnetosphere for reliably isolating signatures from ionospheric currents during geomagnetically quiet times. The effects on the detection of ionospheric currents arising from neglecting the lithospheric and magnetospheric sources are discussed on the example of four Swarm orbits during very quiet times. The respective orbits show a broad range of typical scenarios, such as strong and weak ionospheric signal (during day- and nighttime, respectively) superimposed over strong and weak lithospheric signals. If predictions from the lithosphere or magnetosphere are not properly considered, the amplitude of the ionospheric currents, such as the midlatitude Sq currents or the equatorial electrojet (EEJ), is modulated by 10-15 \% in the examples shown. An analysis from several orbits above the African sector, where the lithospheric field is significant, showed that the peak value of the signatures of the EEJ is in error by 5 \% in average when lithospheric contributions are not considered, which is in the range of uncertainties of present empirical models of the EEJ.}, language = {en} } @article{Denecke2016, author = {Denecke, Klaus-Dieter}, title = {The partial clone of linear terms}, series = {Siberian Mathematical Journal}, volume = {57}, journal = {Siberian Mathematical Journal}, publisher = {Pleiades Publ.}, address = {New York}, issn = {0037-4466}, doi = {10.1134/S0037446616040030}, pages = {589 -- 598}, year = {2016}, abstract = {Generalizing a linear expression over a vector space, we call a term of an arbitrary type tau linear if its every variable occurs only once. Instead of the usual superposition of terms and of the total many-sorted clone of all terms in the case of linear terms, we define the partial many-sorted superposition operation and the partial many-sorted clone that satisfies the superassociative law as weak identity. The extensions of linear hypersubstitutions are weak endomorphisms of this partial clone. For a variety V of one-sorted total algebras of type tau, we define the partial many-sorted linear clone of V as the partial quotient algebra of the partial many-sorted clone of all linear terms by the set of all linear identities of V. We prove then that weak identities of this clone correspond to linear hyperidentities of V.}, language = {en} } @phdthesis{Halecker2016, author = {Halecker, Bastian}, title = {New perspective and insights on business model innovation using systems thinking and action case studies}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-90404}, school = {Universit{\"a}t Potsdam}, pages = {IX, 239}, year = {2016}, abstract = {In recent years, entire industries and their participants have been affected by disruptive technologies, resulting in dramatic market changes and challenges to firm's business logic and thus their business models (BMs). Firms from mature industries are increasingly realizing that BMs that worked successfully for years have become insufficient to stay on track in today's "move fast and break things" economy. Firms must scrutinize the core logic that informs how they do business, which means exploring novel ways to engage customers and get them to pay. This can lead to a complete renewal of existing BMs or innovating completely new BMs. BMs have emerged as a popular object of research within the last decade. Despite the popularity of the BM, the theoretical and empirical foundation underlying the concept is still weak. In particular, the innovation process for BMs has been developed and implemented in firms, but understanding of the mechanisms behind it is still lacking. Business model innovation (BMI) is a complex and challenging management task that requires more than just novel ideas. Systematic studies to generate a better understanding of BMI and support incumbents with appropriate concepts to improve BMI development are in short supply. Further, there is a lack of knowledge about appropriate research practices for studying BMI and generating valid data sets in order to meet expectations in both practice and academia. This paper-based dissertation aims to contribute to research practice in the field of BM and BMI and foster better understanding of the BM concept and BMI processes in incumbent firms from mature industries. The overall dissertation presents three main results. The first result is a new perspective, or the systems thinking view, on the BM and BMI. With the systems thinking view, the fuzzy BM concept is clearly structured and a BMI framework is proposed. The second result is a new research strategy for studying BMI. After analyzing current research practice in the areas of BMs and BMI, it is obvious that there is a need for better research on BMs and BMI in terms of accuracy, transparency, and practical orientation. Thus, the action case study approach combined with abductive methodology is proposed and proven in the research setting of this thesis. The third result stems from three action case studies in incumbent firms from mature industries employed to study how BMI occurs in practice. The new insights and knowledge gained from the action case studies help to explain BMI in such industries and increase understanding of the core of these processes. By studying these issues, the articles complied in this thesis contribute conceptually and empirically to the recently consolidated but still increasing literature on the BM and BMI. The conclusions and implications made are intended to foster further research and improve managerial practices for achieving BMI in a dramatically changing business environment.}, language = {en} } @incollection{KiyHaferSchumannetal.2016, author = {Kiy, Alexander and Hafer, J{\"o}rg and Schumann, Marlen and Enke, Uta}, title = {Digitale Teilnehmerzertifikate und Open Badges verbinden}, series = {DeLFI 2016 - Die 14. E-Learning Fachtagung Informatik 11.-14. September 2016 Potsdam}, booktitle = {DeLFI 2016 - Die 14. E-Learning Fachtagung Informatik 11.-14. September 2016 Potsdam}, number = {P-262}, editor = {Lucke, Ulrike and Schwill, Andreas and Zender, Raphael}, publisher = {Gesellschaft f{\"u}r Informatik}, address = {Bonn}, isbn = {978-3-88579-656-5}, publisher = {Universit{\"a}t Potsdam}, pages = {285 -- 287}, year = {2016}, abstract = {W{\"a}hrend Qualifikationen und Kompetenzen, die auf informellem Wege erworben werden, immer mehr Beachtung finden, stellt sowohl deren Darstellung als auch die Anerkennung ein meist un{\"u}berwindbares Hindernis f{\"u}r Ausstellende und Erwerbende dar. Vermehrt wird unterdessen von klassisch papiergebundenen auf digitale Teilnahmezertifikate umgestellt, um den Nachweis von Kompetenz- und Qualifikationserwerb zu vereinfachen. In diesem Zusammenhang kann die Verbindung von digitalen Teilnahmezertifikaten und Open Badges einen Mehrwert f{\"u}r die {\"o}ffentliche Darstellung und Verifikation bieten.}, language = {de} } @article{Leib2016, author = {Leib, Julia}, title = {Shaping peace: an investigation of the mechanisms underlying post-conflict peacebuilding}, series = {Peace, conflict \& development : an interdisciplinary journal}, journal = {Peace, conflict \& development : an interdisciplinary journal}, number = {22}, publisher = {Univ.}, address = {Bradford}, issn = {1742-0601}, pages = {25 -- 76}, year = {2016}, abstract = {What shapes peace, and how can peace be successfully built in those countries affected by armed conflict? This paper examines mpeacebuilding in the aftermath of civil wars in order to identify the conditions for post-conflict peace. The field of civil war research is characterised by case studies, comparative analyses and quantitative research, which relate relatively little to each other. Furthermore, the complex dynamics of peacebuilding have hardly been investigated so far. Thus, the question remains of how best to enhance the prospects of a stable peace in post-conflict societies. Therefore, it is necessary to capture the dynamics of post-conflict peace. This paper aims at helping to narrow these research gaps by 1) presenting the benefits of set theoretic methods for peace and conflict studies; 2) identifying remote conflict environment factors and proximate peacebuilding factors which have an influence on the peacebuilding process and 3) proposing a set-theoretic multi-method research approach in order to identify the causal structures and mechanisms underlying the complex realm of post-conflict peacebuilding. By implementing this transparent and systematic comparative approach, it will become possible to discover the dynamics of post-conflict peace.}, language = {en} } @article{AbseherMusliuWoltranetal.2016, author = {Abseher, Michael and Musliu, Nysret and Woltran, Stefan and Gebser, Martin and Schaub, Torsten H.}, title = {Shift Design with Answer Set Programming}, series = {Fundamenta informaticae}, volume = {147}, journal = {Fundamenta informaticae}, publisher = {IOS Press}, address = {Amsterdam}, issn = {0169-2968}, doi = {10.3233/FI-2016-1396}, pages = {1 -- 25}, year = {2016}, abstract = {Answer Set Programming (ASP) is a powerful declarative programming paradigm that has been successfully applied to many different domains. Recently, ASP has also proved successful for hard optimization problems like course timetabling and travel allotment. In this paper, we approach another important task, namely, the shift design problem, aiming at an alignment of a minimum number of shifts in order to meet required numbers of employees (which typically vary for different time periods) in such a way that over- and understaffing is minimized. We provide an ASP encoding of the shift design problem, which, to the best of our knowledge, has not been addressed by ASP yet. Our experimental results demonstrate that ASP is capable of improving the best known solutions to some benchmark problems. Other instances remain challenging and make the shift design problem an interesting benchmark for ASP-based optimization methods.}, language = {en} } @phdthesis{Herenz2016, author = {Herenz, Edmund Christian}, title = {Detecting and understanding extragalactic Lyman α emission using 3D spectroscopy}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-102341}, school = {Universit{\"a}t Potsdam}, pages = {175}, year = {2016}, abstract = {In this thesis we use integral-field spectroscopy to detect and understand of Lyman α (Lyα) emission from high-redshift galaxies. Intrinsically the Lyα emission at λ = 1216 {\AA} is the strongest recombination line from galaxies. It arises from the 2p → 1s transition in hydrogen. In star-forming galaxies the line is powered by ionisation of the interstellar gas by hot O- and B- stars. Galaxies with star-formation rates of 1 - 10 Msol/year are expected to have Lyα luminosities of 42 dex - 43 dex (erg/s), corresponding to fluxes ~ -17 dex - -18 dex (erg/s/cm²) at redshifts z~3, where Lyα is easily accessible with ground-based telescopes. However, star-forming galaxies do not show these expected Lyα fluxes. Primarily this is a consequence of the high-absorption cross-section of neutral hydrogen for Lyα photons σ ~ -14 dex (cm²). Therefore, in typical interstellar environments Lyα photons have to undergo a complex radiative transfer. The exact conditions under which Lyα photons can escape a galaxy are poorly understood. Here we present results from three observational projects. In Chapter 2, we show integral field spectroscopic observations of 14 nearby star-forming galaxies in Balmer α radiation (Hα, λ = 6562.8 {\AA}). These observations were obtained with the Potsdam Multi Aperture Spectrophotometer at the Calar-Alto 3.5m Telescope}. Hα directly traces the intrinsic Lyα radiation field. We present Hα velocity fields and velocity dispersion maps spatially registered onto Hubble Space Telescope Lyα and Hα images. From our observations, we conjecture a causal connection between spatially resolved Hα kinematics and Lyα photometry for individual galaxies. Statistically, we find that dispersion-dominated galaxies are more likely to emit Lyα photons than galaxies where ordered gas-motions dominate. This result indicates that turbulence in actively star-forming systems favours an escape of Lyα radiation. Not only massive stars can power Lyα radiation, but also non-thermal emission from an accreting super-massive black hole in the galaxy centre. If a galaxy harbours such an active galactic nucleus, the rate of hydrogen-ionising photons can be more than 1000 times higher than that of a typical star-forming galaxy. This radiation can potentially ionise large regions well outside the main stellar body of galaxies. Therefore, it is expected that the neutral hydrogen from these circum-galactic regions shines fluorescently in Lyα. Circum-galactic gas plays a crucial role in galaxy formation. It may act as a reservoir for fuelling star formation, and it is also subject to feedback processes that expel galactic material. If Lyα emission from this circum-galactic medium (CGM) was detected, these important processes could be studied in-situ around high-z galaxies. In Chapter 3, we show observations of five radio-quiet quasars with PMAS to search for possible extended CGM emission in the Lyα line. However, in four of the five objects, we find no significant traces of this emission. In the fifth object, there is evidence for a weak and spatially quite compact Lyα excess at several kpc outside the nucleus. The faintness of these structures is consistent with the idea that radio-quiet quasars typically reside in dark matter haloes of modest masses. While we were not able to detect Lyα CGM emission, our upper limits provide constraints for the new generation of IFS instruments at 8--10m class telescopes. The Multi Unit Spectroscopic Explorer (MUSE) at ESOs Very Large Telescopeis such an unique instrument. One of the main motivating drivers in its construction was the use as a survey instrument for Lyα emitting galaxies at high-z. Currently, we are conducting such a survey that will cover a total area of ~100 square arcminutes with 1 hour exposures for each 1 square arcminute MUSE pointing. As a first result from this survey we present in Chapter 5 a catalogue of 831 emission-line selected galaxies from a 22.2 square arcminute region in the Chandra Deep Field South. In order to construct the catalogue, we developed and implemented a novel source detection algorithm -- LSDCat -- based on matched filtering for line emission in 3D spectroscopic datasets (Chapter 4). Our catalogue contains 237 Lyα emitting galaxies in the redshift range 3 ≲ z ≲ 6. Only four of those previously had spectroscopic redshifts in the literature. We conclude this thesis with an outlook on the construction of a Lyα luminosity function based on this unique sample (Chapter 6).}, language = {en} } @article{VorburgerNedielkovBrosigetal.2016, author = {Vorburger, Thomas and Nedielkov, Ruslan and Brosig, Alexander and Bok, Eva and Schunke, Emina and Steffen, Wojtek and Mayer, Sonja and Goetz, Friedrich and M{\"o}ller, Heiko Michael and Steuber, Julia}, title = {Role of the Na+-translocating NADH:quinone oxidoreductase in voltage generation and Na+ extrusion in Vibrio cholerae}, series = {Biochimica et biophysica acta : Bioenergetics}, volume = {1857}, journal = {Biochimica et biophysica acta : Bioenergetics}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0005-2728}, doi = {10.1016/j.bbabio.2015.12.010}, pages = {473 -- 482}, year = {2016}, abstract = {For Vibrio cholerae, the coordinated import and export of Na+ is crucial for adaptation to habitats with different osmolarities. We investigated the Na+-extruding branch of the sodium cycle in this human pathogen by in vivo Na-23-NMR spectroscopy. The Na+ extrusion activity of cells was monitored after adding glucose which stimulated respiration via the Na+-translocating NADH:quinone oxidoreductase (Na+-NQR). In a V. cholerae deletion mutant devoid of the Na+-NQR encoding genes (nqrA-F), rates of respiratory Na+ extrusion were decreased by a factor of four, but the cytoplasmic Na+ concentration was essentially unchanged. Furthermore, the mutant was impaired in formation of transmembrane voltage (Delta psi, inside negative) and did not grow under hypoosmotic conditions at pH 8.2 or above. This growth defect could be complemented by transformation with the plasmid encoded nqr operon. In an alkaline environment, Na+/H+ antiporters acidify the cytoplasm at the expense of the transmembrane voltage. It is proposed that, at alkaline pH and limiting Na+ concentrations, the Na+-NQR is crucial for generation of a transmembrane voltage to drive the import of H+ by electrogenic Na+/H+ antiporters. Our study provides the basis to understand the role of the Na+-NQR in pathogenicity of V. cholerae and other pathogens relying on this primary Na+ pump for respiration. (C) 2015 Elsevier B.V. All rights reserved.}, language = {en} } @article{KistnerVollmeyerBurnsetal.2016, author = {Kistner, Saskia and Vollmeyer, Regina and Burns, Bruce D. and Kortenkamp, Ulrich}, title = {Model development in scientific discovery learning with a computer-based physics task}, series = {Computers in human behavior}, volume = {59}, journal = {Computers in human behavior}, publisher = {Elsevier}, address = {Oxford}, issn = {0747-5632}, doi = {10.1016/j.chb.2016.02.041}, pages = {446 -- 455}, year = {2016}, abstract = {Based on theories of scientific discovery learning (SDL) and conceptual change, this study explores students' preconceptions in the domain of torques in physics and the development of these conceptions while learning with a computer-based SDL task. As a framework we used a three-space theory of SDL and focused on model space, which is supposed to contain the current conceptualization/model of the learning domain, and on its change through hypothesis testing and experimenting. Three questions were addressed: (1) What are students' preconceptions of torques before learning about this domain? To do this a multiple-choice test for assessing students' models of torques was developed and given to secondary school students (N = 47) who learned about torques using computer simulations. (2) How do students' models of torques develop during SDL? Working with simulations led to replacement of some misconceptions with physically correct conceptions. (3) Are there differential patterns of model development and if so, how do they relate to students' use of the simulations? By analyzing individual differences in model development, we found that an intensive use of the simulations was associated with the acquisition of correct conceptions. Thus, the three-space theory provided a useful framework for understanding conceptual change in SDL.}, language = {en} } @article{SinclairBussideVilliersetal.2016, author = {Sinclair, Nathalie and Bussi, Maria G. Bartolini and de Villiers, Michael and Jones, Keith and Kortenkamp, Ulrich and Leung, Allen and Owens, Kay}, title = {Recent research on geometry education: an ICME-13 survey team report}, series = {ZDM : The International Journal on Mathematics Education}, volume = {48}, journal = {ZDM : The International Journal on Mathematics Education}, publisher = {Springer}, address = {Heidelberg}, issn = {1863-9690}, doi = {10.1007/s11858-016-0796-6}, pages = {691 -- 719}, year = {2016}, abstract = {This survey on the theme of Geometry Education (including new technologies) focuses chiefly on the time span since 2008. Based on our review of the research literature published during this time span (in refereed journal articles, conference proceedings and edited books), we have jointly identified seven major threads of contributions that span from the early years of learning (pre-school and primary school) through to post-compulsory education and to the issue of mathematics teacher education for geometry. These threads are as follows: developments and trends in the use of theories; advances in the understanding of visuo spatial reasoning; the use and role of diagrams and gestures; advances in the understanding of the role of digital technologies; advances in the understanding of the teaching and learning of definitions; advances in the understanding of the teaching and learning of the proving process; and, moving beyond traditional Euclidean approaches. Within each theme, we identify relevant research and also offer commentary on future directions.}, language = {en} } @article{KistnerBurnsVollmeyeretal.2016, author = {Kistner, Saskia and Burns, Bruce D. and Vollmeyer, Regina and Kortenkamp, Ulrich}, title = {The importance of understanding: Model space moderates goal specificity effects}, series = {The quarterly journal of experimental psychology}, volume = {69}, journal = {The quarterly journal of experimental psychology}, publisher = {Optical Society of America}, address = {Abingdon}, issn = {1747-0218}, doi = {10.1080/17470218.2015.1076865}, pages = {1179 -- 1196}, year = {2016}, abstract = {The three-space theory of problem solving predicts that the quality of a learner's model and the goal specificity of a task interact on knowledge acquisition. In Experiment 1 participants used a computer simulation of a lever system to learn about torques. They either had to test hypotheses (nonspecific goal), or to produce given values for variables (specific goal). In the good- but not in the poor-model condition they saw torque depicted as an area. Results revealed the predicted interaction. A nonspecific goal only resulted in better learning when a good model of torques was provided. In Experiment 2 participants learned to manipulate the inputs of a system to control its outputs. A nonspecific goal to explore the system helped performance when compared to a specific goal to reach certain values when participants were given a good model, but not when given a poor model that suggested the wrong hypothesis space. Our findings support the three-space theory. They emphasize the importance of understanding for problem solving and stress the need to study underlying processes.}, language = {en} } @article{KortenkampMonaghanTrouche2016, author = {Kortenkamp, Ulrich and Monaghan, John and Trouche, Luc}, title = {Jonathan M Borwein (1951-2016): exploring, experiencing and experimenting in mathematics - an inspiring journey in mathematics}, series = {Educational studies in mathematics : an international journal}, volume = {93}, journal = {Educational studies in mathematics : an international journal}, publisher = {Springer}, address = {Dordrecht}, issn = {0013-1954}, doi = {10.1007/s10649-016-9729-0}, pages = {131 -- 136}, year = {2016}, language = {en} } @inproceedings{BenderGrum2016, author = {Bender, Benedict and Grum, Marcus}, title = {Entwicklung eines Architekturkonzepts zum flexiblen Einsatz von Analytics}, series = {Proceedings INFORMATIK - Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. ; Lecture Notes in Informatics (LNI)}, booktitle = {Proceedings INFORMATIK - Jahrestagung der Gesellschaft f{\"u}r Informatik e.V. ; Lecture Notes in Informatics (LNI)}, number = {P259}, publisher = {Gesellschaft f{\"u}r Informatik e.V.}, address = {Bonn}, pages = {815 -- 824}, year = {2016}, abstract = {Die optimale Dimensionierung von IT-Hardware stellt Entscheider aufgrund der stetigen Weiterentwicklung zunehmend vor Herausforderungen. Dies gilt im Speziellen auch f{\"u}r Analytics-Infrastrukturen, die zunehmend auch neue Software zur Analyse von Daten einsetzen, welche in den Ressourcenanforderungen stark variieren. Damit eine flexible und gleichzeitig effiziente Gestaltung von Analytics-Infrastrukturen erreicht werden kann, wird ein dynamisch arbeitendes Architekturkonzept vorgeschlagen, das Aufgaben auf Basis einer systemspezifischen Entscheidungsmaxime mit Hilfe einer Eskalationsmatrix verteilt und hierf{\"u}r Aufgabencharakteristiken sowie verf{\"u}gbare Hardwareausstattungen entsprechend ihrer Auslastung ber{\"u}cksichtigt.}, language = {de} }