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Benincà, Paola — Cecilia Poletto 2004. Topic, focus and V2: Defining the CP sublayers. In: Luigi Rizzi (ed.): The structure of CP and IP: The cartography of syntactic structures, vol. 3, 52–75. Oxford University Press, Oxford

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For a Tychonoff space X, we denote by C p(X) the space of real-valued continuous functions with the topology of pointwise convergence. We show that (a) Arhangel℉skii℉s property (α 2) and the Ramsey property introduced by Nogura and Shakhmatov are equivalent for C p(X), (b) the Ramsey property and Nyikos’ property (α 3/2) are not equivalent for C p(X). These results answer questions posed by Shakhmatov. Concerning properties (α i) for C p(X), some results on Scheepers’ conjecture are also given.

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We prove that there are Tychonoff spaces X for which p(Cp(X)) =ϖ and Cp(X) is a Lindelf Σ-space while the network weight of X is uncountable. This answers Problem 75 from [4]. An example of a space Y is given such that p(Y)=ϖ and Cp(Y) is a Lindelf Σ-space, while the network weight of Y is uncountable. This gives a negative answer to Problem 73 from [4]. For a space X with one non-isolated point a necessary and sufficient condition in terms of the topology on X is given for Cp(X) to have countable point-finite cellularity.

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Summary We prove that, for any Tychonoff  X, the space C p(X) is K-analytic if and only if it has a compact cover {K p: p ? ??} such that K p subset K q whenever p,q ? ?? and p = q. Applying this result we show that if C p(X) is K-analytic then C p(?X) is K-analytic as well. We also establish that a space C p(X) is K-analytic and Baire if and only if X is countable and discrete.

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When radionuclides decay by cascading photons, the accuracy of the measured nuclide activity may be affected by true coincidence summing effects. The effects can be quantified by Monte Carlo simulations that can handle correlated γ-and X-ray emissions from a radionuclide. Analysis techniques are also available commercially to correct for the effects due to cascading γ-rays. The MCNP-CP code was used to compute the effects in high purity germanium detectors for several commonly used nuclides and geometries and the results were compared to measurements and an analysis technique. Excellent agreement in true coincidence summing corrections predicted by MCNP-CP and the analysis technique was obtained. In addition, the X-ray true coincidence summing effects were evaluated.

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, Becker K , Kovesdy CP , Raj DS : Examining associations of

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A potyvírusok családjába tartozó kukorica csíkos mozaik vírus (Maize dwarf mosaic virus, MDMV) az egyszikű növények egyik legjelentősebb kórokozója. Az MDMV genetikai állományának nagyfokú változékonysága és ennek lehetséges patológiai következményei figyelmünket a vírus tüneti determinánsainak és populációjának részletesebb elemzésére irányította. Vizsgálataink a köpenyfehérjét (CP- coat protein) kódoló régió összehasonlító analízisére terjednek ki.

Mintáinkat négy egymást követő évben (2006–2009) két, földrajzilag jól elkülönülő területről, a szegedi Gabonatermesztési Kht. tenyészkertjéből kukoricáról (Zea mays L. convar. saccharata), fenyércirokról (Sorghum halepense (L.) Pers) és szemes cirokról (Sorghum bicolor (L.) Moench), valamint martonvásári tenyészparcellákról gyűjtöttük. A polimeráz láncreakció (PCR) módszerrel felszaporított köpenyfehérje gének nukleinsav sorrendjét meghatároztuk, majd feltérképeztük a vírus molekuláris rokonsági körét. Az izolátumok közti eltérés 0–13,6%-ig terjed, attól függően, hogy a köpenyfehérje gén N-terminális, központi- illetve C-terminális régióját vizsgáltuk. Az összesen nyolcvanhat MDMV izolátum közül öt esetben (Mv0702, Mv0801, Mv0811, Mv0814 és Mv0905) találtunk a köpenyfehérje N-terminális régiójában 13 aminosav hosszúságú inszerciót, ezek az izolátumok az adatbázisban megtalálható Argentin és Spanyol izolátumokkal egy külön csoportot alkotnak. A kapott eredmények azt igazolják, hogy az izolátumok a mintagyűjtés évétől és földrajzi helyétől függetlenül oszlanak el a törzsfán, a populáció stabil.

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Nucleotide and amino acid sequences of the helper component protease (HC-Pro) and the coat protein (CP) of two Hungarian Potato virus Y (PVY) isolates, differing in aphid transmissibility were determined. Isolate PVY-5 belongs to the common “O” strain (PVY O ), whereas isolates PVY-98 and PVY-111 belong to the “N” (PVY N ) and the PVY-NTN and PVY-H to the “NTN” (PVY NTN ) strains, respectively. The PVY-5 isolate varied significantly from the others in aphid transmission and in the ability to systemically infect potato plants. To elucidate whether these differences were due to mutations affecting known functional motifs, the corresponding cistrons of the two proteins were sequenced and aligned. Our analysis showed that none of the well-known motifs, responsible for aphid transmission in the two proteins had been affected. However, the defective isolate had two natural mutations in the HC-Pro in the vicinity of the PTK motif, and a number of mutations in the CP, distributed both in the N-terminus and the central region. As these two proteins are the only known viral participants in the aphid transmission mechanism, it is likely that some of the observed mutations might be involved in this process. Thus, our results indicate that other, previously unidentified sequences or factors may influence virus-vector interactions and transmission of PVY.

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Abstract  

Thermal analysis on two new heterometallic sulfide clusters, [PPh4]2[WS3(CuBr)3]2 and [PPh4]2[MoS3(CuBr)3]2 (where PPh4=tetraphenyl phosphonium, =pentamethylcyclopenta- dienyl), was carried out using a simultaneous TG-DTA unit in an atmosphere of flowing nitrogen and at various heating rates. Supplemented using EDS method, their thermal behavior and properties, together with the composition of their intermediate product, were examined and discussed in connection with their distinctive molecular structure as a dianion, which provided some theoretically and practically significant information. Both clusters decomposed in a two-step mode, but without a stable new phase composed of Mo/W-Cu-S formed during their decomposition process as we expected. Based on TG-DTG data, four methods, i.e. Achar-Brindley-Sharp, Coats-Redfern, Kissinger and Flynn- Wall-Ozawa equation, were used to calculate the non-isothermal kinetic parameters and to determine the most probable mechanisms.

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