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Gil L.,Hebrew University of Jerusalem | Yaron I.,Hebrew University of Jerusalem | Shalitin D.,Hebrew University of Jerusalem | Sauer N.,FAU Erlangen Nurnberg | And 2 more authors.
Plant Journal | Year: 2011

Based on the high density of plasmodesmata interconnecting the intermediary cells and their neighboring phloem parenchyma or bundle-sheath cells, and based on the insensitivity to the sucrose transport inhibitor p- chloromercuribenzenesulfonic acid (PCMBS), cucurbits have been concluded to be symplastic loaders. In the present study, we identified and characterized the full-length sequence of sucrose transporter gene (CmSUT1) from melon (Cucumis melo L. cv. Hale's best jumbo). In vitro experiments confirmed that the identified gene product has sucrose transporter activity in baker's yeast. Healthy and cucumber mosaic virus (CMV)-infected melon plants were employed to examine sucrose transporter activity in planta. Pretreatment with PCMBS inhibited loading of newly fixed 14CO2 into minor veins of CMV-infected plants. Moreover, CMV infection caused significant increase in CmSUT1 transcripts expression, mainly in vascular bundles of minor veins, which was associated with elevated sucrose content in phloem sap collected from source-leaf petioles. We propose that cucurbit plants contain the machinery for apoplastic phloem loading and that CMV infection causes a quantitative shift in the mode by which photoassimilates are loaded into the sieve tube. © 2011 Blackwell Publishing Ltd. Source

Krasnov K.,University of Nottingham | Scarinci C.,FAU Erlangen Nurnberg
Journal of High Energy Physics | Year: 2013

Hodge's formula represents the gravitational MHV amplitude as the determinant of a minor of a certain matrix. When expanded, this determinant becomes a sum over weighted trees, which is the form of the MHV formula first obtained by Bern, Dixon, Perelstein, Rozowsky and rediscovered by Nguyen, Spradlin, Volovich and Wen. The gravity MHV amplitude satisfies the Britto, Cachazo, Feng and Witten recursion relation. The main building block of the MHV amplitude, the so-called half-soft function, satisfies a different, Berends-Giele-type recursion relation. We show that all these facts are illustrations to a more general story. We consider a weighted Laplacian for a complete graph of n vertices. The matrix tree theorem states that its diagonal minor determinants are all equal and given by a sum over spanning trees. We show that, for any choice of a cocycle on the graph, the minor determinants satisfy a Berends-Giele as well as Britto-Cachazo-Feng-Witten type recursion relation. Our proofs are purely combinatorial. © SISSA 2013. Source

Ballesteros A.,University of Burgos | Herranz F.J.,University of Burgos | Meusburger C.,FAU Erlangen Nurnberg
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2014

We show that the Drinfel'd double associated to the standard quantum deformation slη(2,R) is isomorphic to the (2 + 1)-dimensional AdS algebra with the initial deformation parameter η related to the cosmological constant Λ = - η2. This gives rise to a generalisation of a non-commutative Minkowski spacetime that arises as a consequence of the quantum double symmetry of (2 + 1) gravity to non-vanishing cosmological constant. The properties of the AdS quantum double that generalises this symmetry to the case Λ ≠ 0 are sketched, and it is shown that the new non-commutative AdS spacetime is a nonlinear Λ-deformation of the Minkowskian one. © 2014 The Authors. Source

Winner B.,The Interdisciplinary Center | Winkler J.,FAU Erlangen Nurnberg
Cold Spring Harbor Perspectives in Biology | Year: 2015

Adult neurogenesis is limited to specific brain regions in the mammalian brain, such as the hippocampal dentate gyrus and the subventricular zone/olfactory bulb system. Alterations in adult neurogenesis appear to be a common hallmark in different neurodegenerative diseases including Parkinson’s disease (PD), Alzheimer’s disease (AD), and Huntington’s disease (HD). This is remarkable, because the distinct pathological proteins responsible for the different diseases induce the loss of different neural populations. Impaired adult neurogenesis was shown in numerous animal models of neurodegenerative diseases; however, only few post-mortem studies have been performed. We will review concepts related to the interplay between cellular plasticity in regions of adult neurogenesis with a specific focus on cell-autonomous and non-cell-autonomous factors. Furthermore, various strategies aimed to stimulate neuronal plasticity will be discussed within the context of a potential translation into therapeutic approaches for neuropsychiatric symptoms associated with PD, HD, and AD. © 2015 Cold Spring Harbor Laboratory Press; all rights reserved. Source

Dosch M.,FAU Erlangen Nurnberg
KronoScope | Year: 2015

In chapter 55.2 of his Huangji jingshi shu (hjjss, also called neipian †...¯‡ 5.2), Shao Yong makes an explicit statement about the perception of time and its directions. This paragraph contains Shao Yong's temporal epistemology in condensed form. Here he unfolds the perspectivity of the contemplation of time. Gu (old, former, antiquity; past), jin(now, today; present), und hou 3/4(after, later; future) are expressions describing the order of time. Shao Yong asks, what is the perception of time xn (n=1, 2, 3) when contemplated from time xm (m=1, 2, 3)? The answer shows that the designation changes. The designations 'old/past,'now/present,'after/ future'have their meaning only by indication of the point of view. This point of view is the one of the perceiving subject. Moreover, Shao Yong provides a view of other basic aspects of time: direction and continuity. History does not make leaps. A philological and textual examination reveals some of Shao Yong's attitudes towards time and gives a tentative glimpse into his attitude towards divination, conceived of as the observation of future events. © 2015 Koninklijke Brill NV, Leiden, The Netherlands. Source

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