Structure Theorem and Strict Alternation Hierarchy for FO^2 on Words

It is well-known that every first-order property on words is expressible using at most three variables. The subclass of properties expressible with only two variables is also quite interesting and well-studied. We prove precise structure theorems that characterize the exact expressive power of first-order logic with two variables on words. Our results apply to both the case with and without a successor relation. For both languages, our structure theorems show exactly what is expressible using a given quantifier depth, n, and using m blocks of alternating quantifiers, for any m \leq n. Using these characterizations, we prove, among other results, that there is a strict hierarchy of alternating quantifiers for both languages. The question whether there was such a hierarchy had been completely open. As another consequence of our structural results, we show that satisfiability for first-order logic with two variables without successor, which is NEXP-complete in general, becomes NP-complete once we only consider alphabets of a bounded size

TPU positioning in the global research and educational environment

Томск вошел в число инновационных городов мира по результатам авторитетного рейтинга "Innovation Cities Global Index 2012-2013". Всего в рейтинг попали 445из 1542 городов мира, где проводились исследования. Российских городов - 20. Большой вклад в инновационную составляющую города вносит Томский консор-циум научно-образовательных и научных организаций, возглавляемый ректором ТПУ П.С. Чубиком. Университеты становятся активными игроками не только в производстве новых знаний, но и в их распространении и использовании посредствоминновационной деятельности.Tomsk is rated as one of the global innovative cities by the reputable ranking Innovation Cities Global Index 2012-2013. The survey covered 1542 cities of the world, with 445 ofthem having been included in the ranked list. There were 20 Russian cities rated. A great contribution to the Tomsk innovative component is provided by Tomsk Consortium ofResearch and Educational Organizations headed by P.S. Chubik, TPU Rector. Universities are becoming actively involved not only in the generation of new knowledge, but also in its dissemination and application by means of innovative activities

Chemical composition of modern and fossil hippopotamid teeth and implications for paleoenvironmental reconstructions and enamel formation : part 2, alkaline earth elements as tracers of watershed hydrochemistry and provenance

This study demonstrates that alkaline earth elements in enamel of hippopotamids, in particular Ba and Sr, are tracers for water provenance and hydrochemistry in terrestrial settings. The studied specimens are permanent premolar and molar teeth found in modern and fossil lacustrine sediments of the Western Branch of the East African Rift system (Lake Kikorongo, Lake Albert, and Lake Malawi) and from modern fluvial environments of the Nile River. Concentrations in enamel vary by two orders of magnitude for Ba (120–9336 μg g−1) as well as for Sr (9–2150 μg g−1). The variations are partially induced during post-mortem alteration and during amelogenesis, but the major contribution originates ultimately from the variable water chemistry in the habitats of the hippopotamids which is controlled by the lithologies and weathering processes in the watershed areas. Amelogenesis causes a distinct distribution of MgO, Ba and Sr in modern and fossil enamel, in that element concentrations increase along profiles from the outer rim towards the enamel–dentin junction by a factor of 1.3–1.9. These elements are well correlated in single specimens, thus suggesting that their distribution is determined by a common, single process, which can be described by closed system Rayleigh crystallization of bioapatite in vivo. Enamel from most hippopotamid specimens has Sr/Ca and Ba/Ca which are typical for herbivores. However, Ba/Sr ranges from 0.1 to 3 and varies on spatial and temporal scales. Thus, Sr concentrations and Ba/Sr in enamel differentiate between habitats having basaltic mantle rocks or Archean crustal rocks as the ultimate sources of Sr and Ba. This provenance signal is modulated by climate change. In Miocene to Pleistocene enamel from the Lake Albert region, Ba/Sr decreases systematically with time from 2 to 0.5. This trend can be correlated with changes in climate from humid to arid, in vegetation from C3 to C4 biomass as well as with increasing evaporation of the lake water. The most plausible explanation is that Ba mobility decreased with increasing aridification due to preferential deposition with clay and Fe-oxide-hydroxide or barite on the watershed of Lake Albert

Cosmic rays in astrospheres

Cosmic rays passing through large astrospheres can be efficiently cooled inside these "cavities" in the interstellar medium. Moreover, the energy spectra of these energetic particles are already modulated in front of the astrospherical bow shocks. We study the cosmic ray flux in and around lambda Cephei as an example for an astrosphere. The large-scale plasma flow is modeled hydrodynamically with radiative cooling. We studied the cosmic ray flux in a stellar wind cavity using a transport model based on stochastic differential equations. The required parameters, most importantly, the elements of the diffusion tensor, are based on the heliospheric parameters. The magnetic field required for the diffusion coefficients is calculated kinematically. We discuss the transport in an astrospheric scenario with varying parameters for the transport coefficients. We show that large stellar wind cavities can act as sinks for the galactic cosmic ray flux and thus can give rise to small-scale anisotropies in the direction to the observer. Small-scale cosmic ray anisotropies can naturally be explained by the modulation of cosmic ray spectra in huge stellar wind cavities

Johann Friedrich Schannat erlernt die Praktiken der (kirchen-)historischen Gelehrsamkeit

Zusammenfassung: Alle Praktiken von Gelehrsamkeit stehen in Re­lation zu «epistemischen Tugenden», also einem Bezugsrahmen für den Gelehrten im Umgang mit seinem Material ebenso wie mit seiner sozialen Umgebung. Wenn diese Feststellung für alle Mit­glieder der Res publica literaria gilt, so tut sie dies in verstärktem Ausmaß für diejenigen unter ihnen, die sich bei ihrer Befassung mit Kirchengeschichte in einem institutionellen Rahmen bewegen, der ei­nige dieser Tugenden und Praktiken gleichsam in einen normativen Rang zu erheben vermag. Oft im Spannungsfeld dieser Pole angesiedelt, legen Gele­hrtenkorrespondenzen beredtes Zeugnis ab von der Erlernung und Anwendung, jedoch auch von der Ablehnung und Infragestellung solcher Praktiken und Tugenden durch die Gelehrten. Aus dieser theoretischen Perspektive bietet der vorliegenden Beitrag eine selektive Analyse der Korrespondenz von Johann Friedrich Schannat (1683–1739), einem aus Luxemburg stammenden Gelehrten im Dienst unterschiedlicher kirchlicher Würdenträger (Fulda, Worms, Prag) und damit zugleich einem «wandern­den» Kirchenhistoriker: Indem er nicht an einen archivischen oder bibliothekarischen Bestand und ebenso wenig an ein spezifisches patronales Umfeld dauerhaft gebunden war, musste Schannat sein Re­pertoire an Praktiken und Tugenden stets neu ak­tualisieren. Je nach Position des brieflichen Gegenü­bers konnten diesen unterschiedliche intellektuelle und soziale Ausprägungen zukommen, wie an den Briefwechseln Schannats mit dem Freiherrn Wil­helm von Crassier, dem Mauriner Edmond Martène und dem österreichischen Benediktinergelehrten Bernhard Pez deutlich wird. Abstract: All practices of erudition are related to «epis­temic virtues», meaning a reference frame for scholars defining how to interact with their objects and their social environment. If this as­sumption holds true for all members of the Res publica literaria, it does so even more for those who, in dealing with ecclesiastical history, are part of an institutional framework that elevates some of those practices and virtues to a norma­tive level. Often situated between these poles, learned correspondences testify to the learning and application, but also to the refusal and ques­tioning of such virtues and practices. Viewed from this theoretical basis, the presented paper offers a selective analysis of the corresponden­ce of Johann Friedrich Schannat (1683–1739), a scholar from Luxembourg who entered the ser­vices of various ecclesiastical dignitaries (Fulda, Worms, Prague), thereby becoming an «itine­rant» church historian: Not bound by long-las­ting ties to a specific archive or library, or to an individual environment of patronage, Schannat was required to constantly re-adapt his reper­toire of practices and virtues. Depending on the position of the correspondence partner, his framework of reference could assume different intellectual and social characteristics, as illus­trated by his correspondences with the Baron Crassier, the Maurist Martène and the Austrian Benedictine scholar Bernhard Pez. Stichwörter: Frühe Neuzeit, Res publica literaria, Gelehrtenkorres­pondenz, Kirchengeschichtsschreibung, Historiogra­phiegeschichte, Historische Epistemologie, Epistemische Tugenden. Key words: Early modern history, res publica literaria, eru­dite correspondence, ecclesiastical historiogra­phy, history of historiography, historical episte­mology, epistemic virtues

« Britain’s best kept secret » : la machine Enigma et le décodage des messages durant la Seconde Guerre mondiale

L’Enigma et ses cylindres permutables (Coll. Württembergische Landesbibliothek Stuttgart) © et cliché Württembergische Landesbibliothek Stuttgart / Larissa Arlt Un des plus grands mystères de la Seconde Guerre mondiale fut le décodage réussi des messages radio que les Allemands avaient cryptés grâce à la machine à coder « Enigma » (voir ill. ci-dessus). Jürgen Rohwer, ancien directeur de la Bibliothèque d’histoire contemporaine (Bibliothek für Zeitgeschichte–BfZ), s’est livré à des recherche..

Area-storage capacity curve of historic artificial water reservoir ottergrung, Slovakia - assessment of the historical data with the use of gis tools

The main goal of this work was to verify the historic data of historic artificial water reservoir Ottergrund, Banska Stiavnica district, which is inscribed in the UNESCO world heritage list. Main focus was set to area-storage capacity curve. There is historic map with the display of reservoir bottom contours and area-storage capacity curve in a paper format. These data were analysed and compared with the results of the calculation of area-storage capacity curve that was performed with the use of a new tool with named "ASC_Curve", which is based on Python script. This tool utilizes ArcPy site package and it works with the TIN model of water reservoir bottom. In case of water reservoir Ottergrund we created the TIN model of the historic bottom; input data for the TIN model creation was the historic contour plan. The results of the analysis have shown that the storage capacity calculated with the use of the developed ASC_Curve tool is 97% of the volume mentioned in the historic map. Analysis has also show the minor mathematical errors in the calculations of the area-storage capacity data in historic contour plan. This tool can also be used also for the analysis of the current storage capacity conditions of the water reservoirs, if the surveying with echosounding equipment is performed to obtain the data to produce the TIN model of the water reservoir bottom.APVV [SK-PT-2015-0005]; VEGA [1/0456/14, 2/0050/14]; [APVV-15-0562]info:eu-repo/semantics/publishedVersio

Partial cooperative unfolding in proteins as observed by hydrogen exchange mass spectrometry

This is an Accepted Manuscript of an article published by Taylor & Francis in International Reviews in Physical Chemistry on 2013-1-1, available online: http://www.tandfonline.com/10.1080/0144235X.2012.751175.Many proteins do not exist in a single rigid conformation. Protein motions, or dynamics, exist and in many cases are important for protein function. The analysis of protein dynamics relies on biophysical techniques that can distinguish simultaneously existing populations of molecules and their rates of interconversion. Hydrogen exchange (HX) detected by mass spectrometry (MS) is contributing to our understanding of protein motions by revealing unfolding and dynamics on a wide timescale, ranging from seconds to hours to days. In this review we discuss HX MS-based analyses of protein dynamics, using our studies of multi-domain kinases as examples. Using HX MS, we have successfully probed protein dynamics and unfolding in the isolated SH3, SH2 and kinase domains of the c-Src and Abl kinase families, as well as the role of inter- and intra-molecular interactions in the global control of kinase function. Coupled with high-resolution structural information, HX MS has proved to be a powerful and versatile tool for the analysis of the conformational dynamics in these kinase systems, and has provided fresh insight regarding the regulatory control of these important signaling proteins. HX MS studies of dynamics are applicable not only to the proteins we illustrate here, but to a very wide range of proteins and protein systems, and should play a role in both classification of and greater understanding of the prevalence of protein motion