944 research outputs found

    The single-particle density matrix and the momentum distribution of dark "solitons" in a Tonks-Girardeau gas

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    We study the reduced single-particle density matrix (RSPDM), the momentum distribution, natural orbitals and their occupancies, of dark "soliton" (DS) states in a Tonks-Girardeau gas. DS states are specially tailored excited many-body eigenstates, which have a dark solitonic notch in their single-particle density. The momentum distribution of DS states has a characteristic shape with two sharp spikes. We find that the two spikes arise due to the high degree of correlation observed within the RSPDM between the mirror points (xx and x-x) with respect to the dark notch at x=0x=0; the correlations oscillate rather than decay as the points xx and x-x are being separated.Comment: 9 pages, 8 figure

    EU Peatlands: Current Carbon Stocks and Trace Gas Fluxes

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    Peatlands in Europe has formed a significant sink for atmospheric CO2 since the last glacial maximum. Currently they are estimated to hold ca. 42 Gt carbon in the form of peat and are therefore a considerable component in the European carbon budget. Due to the generally wet soil conditions in peatlands they are also significant emitters of the strong greenhouse gas (GHG) methane (CH4) and in some cases also of nitrous oxide (N2O). The EU funded CarboEurope-GHG Concerted Action attempts to develop a reliable and complete greenhouse gas budget for Europe and this report aims to provide a review and synthesis of the available information about GHG exchanges in European peatlands and their underlying processes. A best estimate for all the European countries shows that some are currently sinks for atmospheric CO2 while others are sources. In contrast, for CH4 and N2O, only the sources are relevant. Whilst some countries are CO2 sinks, all countries are net GHG emitters from peatlands. The results presented, however, carry large uncertainties, which cannot be adequately quantified yet. One outstanding uncertainty is the distribution of land use types, particular in Russia, the largest European peat nation. The synthesis of GHG exchange, nevertheless, indicates some interesting features. Russia hosts an estimated 41% of European peatlands and contributes most to all GHG exchanges (CO2: 25%, CH4: 52%, N2O: 26%, Total: 37%). Germany is the second-largest emitter (12% of European total) although it contains only 3.2% of European peatlands. The reason is the use of most of the peatland area for intensive cropland and grassland. The largest CO2 emitters are countries with large agricultural peatland areas (Russia, Germany, Belarus, Poland), the largest N2O emitters are those with large agricultural fen areas (Russia, Germany, Finland). In contrast, the largest CH4 emitters are concentrated in regions with large areas of intact mires, namely Russia and Scandinavia. High average emission densities above 3.5 t C-equiv. ha-1 are found in the Southeast Mediterranean, Germany and the Netherlands where agricultural use of peatlands is intense. Low average emission densities below 0.3 t C-equiv. ha-1 occur where mires and peatland forests dominate, e.g. Finland and the UK. This report concludes by pointing at key gaps in our knowledge about peatland carbon stocks and GHG exchanges which include insufficient basic information on areal distribution of peatlands, measurements of peat depth and also a lack of flux datasets providing full annual budgets of GHG exchanges

    Synthesis of a quinolone library from ynones

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    A library of 72 quinolones was synthesized from substituted anthranilic acids, using ynone intermediates. These masked β-dicarbonyl synthons allowed cyclization under milder conditions than previously reported quinolone syntheses

    Extracellular vesicles provide a capsid-free vector for oncolytic adenoviral DNA delivery

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    Extracellular vesicles (EVs) have been showcased as auspicious candidates for delivering therapeutic cargo, including oncolytic viruses for cancer treatment. Delivery of oncolytic viruses in EVs could provide considerable advantages, hiding the viruses from the immune system and providing alternative entry pathways into cancer cells. Here we describe the formation and viral cargo of EVs secreted by cancer cells infected with an oncolytic adenovirus (IEVs, infected cell-derived EVs) as a function of time after infection. IEVs were secreted already before the lytic release of virions and their structure resembled normally secreted EVs, suggesting that they were not just apoptotic fragments of infected cells. IEVs were able to carry the viral genome and induce infection in other cancer cells. As such, the role of EVs in the life cycle of adenoviruses may be an important part of a successful infection and may also be harnessed for cancer- and gene therapy.Peer reviewe

    A relativistic study of Bessel beams

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    We present a fully relativistic analysis of Bessel beams revealing some noteworthy features that are not explicit in the standard description. It is shown that there is a reference frame in which the field takes a particularly simple form, the wave appearing to rotate in circles. The concepts of polarization and angular momentum for Bessel beams is also reanalyzed.Comment: 11 pages, 2 fig

    Interval valued (\in,\ivq)-fuzzy filters of pseudo BLBL-algebras

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    We introduce the concept of quasi-coincidence of a fuzzy interval value with an interval valued fuzzy set. By using this new idea, we introduce the notions of interval valued (\in,\ivq)-fuzzy filters of pseudo BLBL-algebras and investigate some of their related properties. Some characterization theorems of these generalized interval valued fuzzy filters are derived. The relationship among these generalized interval valued fuzzy filters of pseudo BLBL-algebras is considered. Finally, we consider the concept of implication-based interval valued fuzzy implicative filters of pseudo BLBL-algebras, in particular, the implication operators in Lukasiewicz system of continuous-valued logic are discussed

    Soviet-Polish relations, 1919-1921

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    The Polish-Soviet War of 1919-1921 was a direct consequence of the ideological objectives pursued by the belligerents. Ideology shaped the political agenda and the diametrically opposed war aims of both states, and was implemented through the foreign policy, diplomatic negotiation and military engagements pursued. This proved to be the principal obstacle to the establishment of cordial relations. As western democracy and Russian Marxism battled it out, war was inevitable. Externally, the Paris Peace Conference provided the necessary conditions for the resumption of traditional Russian-Polish hostilities, whilst the Allied States consistently demonstrated their absolute inability to directly influence either the development, or outcome, of the conflict. Redressing the balance of historiography, this thesis includes a greater examination of the conflict from the perspective of the Soviet regime. This firmly controlled the Russian decision-making process. By charting the war, it becomes clear that both states deliberately pursued a dual offensive: traditional diplomatic negotiation and military campaign as conditions dictated. However, in addition, Soviet Russia developed a unique and innovative, revolutionary, agit-prop, diplomatic medium. This enabled adept Soviet diplomats to win the majority of diplomatic battles during the conflict, although often negotiating from a militarily weak position. Nevertheless, the regime ultimately failed in its objective: to ignite socialist revolution in western Europe. The mistaken Soviet decision in July 1920 to cross the ethnographic border to forcefully sovietise Poland, in opposition to Marxist doctrine, irreversibly altered the complexion of the war and proved its pivotal turning point. This culminated politically with the short-lived establishment of the Provisional Revolutionary Committee in Białystok, and militarily, with the decisive defeat of the Red Army at the Battle of Warsaw. It is now certain that the Red Army offensive into Poland in July 1920 aimed not only at the sovietisation of Poland, but at spreading the socialist revolution to Western Europe and overthrowing the Versailles settlement. The European revolutionary upsurge had largely extinguished during the previous year and in August 1920, Communist ideology ultimately failed to inspire the vast majority of the Polish population. Thus, by utilising the Soviet military to secure its war aims, Lenin and the Politburo inadvertently signed the death-warrant of socialist revolution in Poland at the beginning of the twentieth century.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Epstein-Barr virus (EBV)-encoded small RNAs (EBERs) associated with poor prognosis of head and neck carcinomas

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    BACKGROUND: Epstein-Barr virus (EBV) is the main cause of nasopharyngeal carcinoma (NPC), also found in other head and neck carcinomas (HNSCCs) where its role remains controversial.RESULTS: EBV was found in 80% and 21% of the samples with PCR and ISH (in cancer cells), respectively. Eight of ISH-positive samples were not NPCs. EBER-RNA detection in carcinoma cells was associated with worse prognosis, whether or not NPCs were included. HPV/EBV and HSV/HPV coinfections associated with a shorter survival. LMP-1 expression, positive in 51% of samples did not correlate with the disease outcome.MATERIALS AND METHODS: We analyzed EBV in 73 HNSCC samples with a known HPV and HSV-1 status, using in situ hybridization (ISH) and immunohistochemistry (IHC) for EBV-early transcripts (EBER) and LMP-1 protein, respectively. EBV-DNA was detected with a Luminex-based method. The results were correlated with HPV-status and disease outcome.CONCLUSIONS: EBV is transcriptionally active in NPC cells but also in a subgroup of other HNSCCs.</p
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