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Greek and Romance unagreement in Calabria
The term âunagreementâ describes configurations with an apparent person-mismatch between a typically definite plural subject and non-third person verbal agreement found in several null subject languages. Previous works have suggested that languages which have an obligatory definite article in adnominal pronoun constructions (APCs) allow unagreement (cf. standard modern Greek emeis oi glossologoi âwe (the) linguistsâ),
while languages that rule out definite articles in APCs do not allow unagreement constructions (cf. standard Italian noi (*i) linguisti). This article presents new evidence from Calabrian Greek (Greko), which corresponds to the predictions for other varieties of Greek, and two southern Italian Romance varieties (northern and southern
Calabrese): these varieties exhibit Italian-type apcs but still allow unagreement, contrary to expectations. We discuss how the Romance data may be accommodated by extending a previous account of unagreement and propose that the hybrid pattern observed in the Italo-Romance varieties is a result of historical contact with local Greek
varieties.Georg Höhn acknowledges funding from the European Research Council Advanced Grant No. 269752 âRethinking Comparative Syntaxâ for part of this research. Giuseppina Silvestri acknowledges funding from the Leverhulme-funded project âFading voices in southern Italy: investigating languag
Karotten von der Saat bis zum Teller - Einfluss von Sorte Standort, Jahr und Anbauweise auf den Mineralstoffgehalt
Wie wertvoll sind Karotten fĂŒr unsere ErnĂ€hrung? Die Fachwelt ist sich einig, dass der tĂ€gliche Konsum von FrĂŒchten und GemĂŒse erhöht werden soll. Es gibt jedoch Presseberichte, die den ernĂ€hrungsphysiologischen Wert von heutigem GemĂŒse hinterfragen. Die Rolle der Karotte als Mineralstoffquelle wird durchleuchtet
Quantitative and qualitative biogenic silicon analyses combining modern microscopical and spectroscopical methods
Numerous organisms comprising pro- and eukaryotes are evolutionarily adapted to synthesize siliceous structures (biosilicification). In terrestrial biogeosystems biogenic silicon (BSi) accumulation of phytogenic (BSi synthesized by plants), protistic (diatoms and testate amoeba), microbial (bacteria and fungi) and zoogenic (sponges) origin results in formation of corresponding BSi pools. Accumulation and recycling of BSi in terrestrial ecosystems influence fluxes of dissolved Si from the continents to the oceans, thus act as a filter in the global Si cycle. Although the biogenic control mechanism especially of phytogenic Si pools (phytoliths) has been generally recognized since decades quantitative information on other terrestrial BSi pools is rare. Additionally, information on physicochemical properties of the various siliceous structures are needed to better understand their dissolution kinetics. We used modern microscopical (laser scanning microscopy, LSM; Scanning electron microscopy with coupled energy-dispersive X-ray spectroscopy, SEM-EDX) and spectroscopical (micro-Fourier transform infrared spectroscopy, micro-FTIR) methods for quantitative and qualitative analyses of BSi structures. LSM was used to measure volumes and surface areas of BSi structures and corresponding surface-area-to-volume ratios (A:V ratios) were calculated as an indicator for the resistibility of these siliceous structures against dissolution. Volume measurements were also used for the quantification of BSi pools by multiplication of corresponding volumes with BSi density. SEM-EDX analyses provided information on the elemental composition of different BSi structures and with the help of micro-FTIR we were able to gain specific information about chemical bonding and molecular structures of BSi. These information will help us to understand in detail dissolution kinetics of various siliceous structures, thus their role in Si cycling
Cut it out: Out-of-plane stresses in cell sheet folding of Volvox embryos
The folding of cellular monolayers pervades embryonic development and
disease. It results from stresses out of the plane of the tissue, often caused
by cell shape changes including cell wedging via apical constriction. These
local cellular changes need not however be compatible with the global shape of
the tissue. Such geometric incompatibilities lead to residual stresses that
have out-of-plane components in curved tissues, but the mechanics and function
of these out-of-plane stresses are poorly understood, perhaps because their
quantification has proved challenging. Here, we overcome this difficulty by
combining laser ablation experiments and a mechanical model to reveal that such
out-of-plane residual stresses exist and also persist during the inversion of
the spherical embryos of the green alga Volvox. We show how to quantify the
mechanical properties of the curved tissue from its unfurling on ablation, and
reproduce the tissue shape sequence at different developmental timepoints
quantitatively by our mechanical model. Strikingly, this reveals not only clear
mechanical signatures of out-of-plane stresses associated with cell shape
changes away from those regions where cell wedging bends the tissue, but also
indicates an adaptive response of the tissue to these stresses. Our results
thus suggest that cell sheet folding is guided mechanically not only by cell
wedging, but also by out-of-plane stresses from these additional cell shape
changes.Comment: 10 pages, 3 figures; Supporting Information: 10 pages, 2 figure
Spectral Orbits and Peak-to-Average Power Ratio of Boolean Functions with respect to the {I,H,N}^n Transform
We enumerate the inequivalent self-dual additive codes over GF(4) of
blocklength n, thereby extending the sequence A090899 in The On-Line
Encyclopedia of Integer Sequences from n = 9 to n = 12. These codes have a
well-known interpretation as quantum codes. They can also be represented by
graphs, where a simple graph operation generates the orbits of equivalent
codes. We highlight the regularity and structure of some graphs that correspond
to codes with high distance. The codes can also be interpreted as quadratic
Boolean functions, where inequivalence takes on a spectral meaning. In this
context we define PAR_IHN, peak-to-average power ratio with respect to the
{I,H,N}^n transform set. We prove that PAR_IHN of a Boolean function is
equivalent to the the size of the maximum independent set over the associated
orbit of graphs. Finally we propose a construction technique to generate
Boolean functions with low PAR_IHN and algebraic degree higher than 2.Comment: Presented at Sequences and Their Applications, SETA'04, Seoul, South
Korea, October 2004. 17 pages, 10 figure
On Exceptional Vertex Operator (Super) Algebras
We consider exceptional vertex operator algebras and vertex operator
superalgebras with the property that particular Casimir vectors constructed
from the primary vectors of lowest conformal weight are Virasoro descendents of
the vacuum. We show that the genus one partition function and characters for
simple ordinary modules must satisfy modular linear differential equations. We
show the rationality of the central charge and module lowest weights,
modularity of solutions, the dimension of each graded space is a rational
function of the central charge and that the lowest weight primaries generate
the algebra. We also discuss conditions on the reducibility of the lowest
weight primary vectors as a module for the automorphism group. Finally we
analyse solutions for exceptional vertex operator algebras with primary vectors
of lowest weight up to 9 and for vertex operator superalgebras with primary
vectors of lowest weight up to 17/2. Most solutions can be identified with
simple ordinary modules for known algebras but there are also four conjectured
algebras generated by weight two primaries and three conjectured extremal
vertex operator algebras generated by primaries of weight 3, 4 and 6
respectively.Comment: 37 page
Karotten von der Saat bis zum Teller - Einfluss von Sorte, Standort, Jahr, Anbauweise und Lagerung auf den Carotingehalt
Karotten sind ergiebige Quellen an a- und Ă-Carotin und weiterer sekundĂ€rer Pflanzenstoffe (SPS). Es ist bekannt, dass viele SPS auch fĂŒr Geschmack, Aroma und Farbe eine Rolle spielen. Der Einfluss von Vorernte- und Nacherntefaktoren auf den Gehalt an SPS gewinnt deshalb zunehmend an Bedeutung. FĂŒr die Entwicklung eines QualitĂ€tssicherungskonzepts sind die Kenntnisse ĂŒber die Auswirkung dieser Faktoren unumgĂ€nglich
Effective relational dynamics
We provide a synopsis of an effective approach to the problem of time in the
semiclassical regime. The essential features of this new approach to evaluating
relational quantum dynamics in constrained systems are illustrated by means of
a simple toy model.Comment: 4 pages, based on a talk given at Loops '11 in Madrid, to appear in
Journal of Physics: Conference Series (JPCS
Effective approach to the problem of time: general features and examples
The effective approach to quantum dynamics allows a reformulation of the
Dirac quantization procedure for constrained systems in terms of an
infinite-dimensional constrained system of classical type. For semiclassical
approximations, the quantum constrained system can be truncated to finite size
and solved by the reduced phase space or gauge-fixing methods. In particular,
the classical feasibility of local internal times is directly generalized to
quantum systems, overcoming the main difficulties associated with the general
problem of time in the semiclassical realm. The key features of local internal
times and the procedure of patching global solutions using overlapping
intervals of local internal times are described and illustrated by two quantum
mechanical examples. Relational evolution in a given choice of internal time is
most conveniently described and interpreted in a corresponding choice of gauge
at the effective level and changing the internal clock is, therefore,
essentially achieved by a gauge transformation. This article complements the
conceptual discussion in arXiv:1009.5953.Comment: 42 pages, 9 figures; v2: streamlined discussions, more compact
manuscrip
Spinning around or stagnation - what do osteoblasts and chondroblasts really like?
<p>Abstract</p> <p>Objective</p> <p>The influcence of cytomechanical forces in cellular migration, proliferation and differentation of mesenchymal stem cells (MSCs) is still poorly understood in detail.</p> <p>Methods</p> <p>Human MSCs were isolated and cultivated onto the surface of a 3 Ă 3 mm porcine collagen I/III carrier. After incubation, cell cultures were transfered to the different cutures systems: regular static tissue flasks (group I), spinner flasks (group II) and rotating wall vessels (group III). Following standard protocols cells were stimulated lineage specific towards the osteogenic and chondrogenic lines. To evaluate the effects of applied cytomechanical forces towards cellular differentiation distinct parameters were measured (morphology, antigen and antigen expression) after a total cultivation period of 21 days in vitro.</p> <p>Results</p> <p>Depending on the cultivation technique we found significant differences in both gen and protein expression.</p> <p>Conclusion</p> <p>Cytomechanical forces with rotational components strongly influence the osteogenic and chondrogenic differentiation.</p
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