1,095 research outputs found

    Synthesis and biological evaluation of phosphonated dihydroisoxazole nucleosides

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    Phosphonated isoxazolinyl nucleosides have been prepared via 1,3-dipolar cycloaddition reaction of nitrile oxides with corresponding vinyl or allyl nucleobases for antiviral studies. The cytotoxicity, the anti-HSV activity and the RT-inhibitory activity of the obtained compounds were evaluated and compared with those of AZT and diethyl{(10SR,40RS)-10-[[(5-methyl-2,4-dioxo-3,4- dihydropyrimidin-1(2H)-yl)]-30-methyl-20-oxa-30-azacyclopent-40-yl]}methylphosphonate, a saturated phosphonated dihydroisoxazole nucleoside analogue

    Domestication as innovation : the entanglement of techniques, technology and chance in the domestication of cereal crops

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    The origins of agriculture involved pathways of domestication in which human behaviours and plant genetic adaptations were entangled. These changes resulted in consequences that were unintended at the start of the process. This paper highlights some of the key innovations in human behaviours, such as soil preparation, harvesting and threshing, and how these were coupled with genetic ‘innovations’ within plant populations. We identify a number of ‘traps’ for early cultivators, including the needs for extra labour expenditure on crop-processing and soil fertility maintenance, but also linked gains in terms of potential crop yields. Compilations of quantitative data across a few different crops for the traits of nonshattering and seed size are discussed in terms of the apparently slow process of domestication, and parallels and differences between different regional pathways are identified. We highlight the need to bridge the gap between a Neolithic archaeobotanical focus on domestication and a focus of later periods on crop-processing activities and labour organization. In addition, archaeobotanical data provide a basis for rethinking previous assumptions about how plant genetic data should be related to the origins of agriculture and we contrast two alternative hypotheses: gradual evolution with low selection pressure versus metastable equilibrium that prolonged the persistence of ‘semi-domesticated’ populations. Our revised understanding of the innovations involved in plant domestication highlight the need for new approaches to collecting, modelling and integrating genetic data and archaeobotanical evidence

    Phosphonated Carbocyclic 2'-Oxa-3'-azanucleosides as New Antiretroviral Agents

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    Phosphonated carbocyclic 2¢-oxa-3¢-azanucleosides have been synthesized and tested for their antiretroviral activity. The obtained results have shown that some of the compounds were as powerful as azydothymidine in inhibiting the reverse transcriptase activity of the human retrovirus T-cell leukemia/lymphotropic virus type 1 and in protecting human peripheral blood mononuclear cells against human retrovirus T-cell leukemia/ lymphotropic virus type 1 transmission in vitro. These data indicate that phosphonated carbocyclic 2¢-oxa- 3¢-azanucleosides possess the necessary requirements to efficiently counteract infections caused by human retroviruses

    Synthesis of phosphonated carbocyclic 2 '-oxa-3 '-aza-nucleosides: Novel inhibitors of reverse transcriptase

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    Phosphonated carbocyclic 2'-oxa-3'-aza-nucleosides have been synthesized in good yields by 1,3-dipolar cycloaddition methodology. The cytotoxicity and the reverse transcriptase inhibitory activity of the obtained compounds have been investigated. Phosphonated carbocyclic 2'-oxa-3'-aza-nucleosides, while showing low levels of cytotoxicity, exert a specific inhibitor activity on two different reverse transcriptases, which is comparable with that of AZT, opening new perspectives on their possible use as therapeutic agents, in anti-retroviral and anti-HBV chemotherapy

    Hepatic intra-arterial versus intravenous fotemustine in patients with liver metastases from uveal melanoma (EORTC 18021): a multicentric randomized trial

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    Despite an improved antitumor efficacy as noticed by an enhanced response rate and an improved progression-free survival, the hepatic intra-arterial fotemustine did not increase the overall survival of uveal melanoma patients with liver metastases only. We propose to consider intrahepatic treatment as an experimental approac

    Exploring the Neutrinoless Double Beta Decay in the Inverted Neutrino Hierarchy with Bolometric Detectors

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    Neutrinoless double beta decay (0nubb) is one of the most sensitive probes for physics beyond the Standard Model, providing unique information on the nature of neutrinos. In this paper we review the status and outlook for bolometric 0nubb decay searches. We summarize recent advances in background suppression demonstrated using bolometers with simultaneous readout of heat and light signals. We simulate several configurations of a future CUORE-like bolometer array which would utilize these improvements and present the sensitivity reach of a hypothetical next-generation bolometric 0nubb experiment. We demonstrate that a bolometric experiment with the isotope mass of about 1 ton is capable of reaching the sensitivity to the effective Majorana neutrino mass (|mee|) of order 10-20 meV, thus completely exploring the so-called inverted neutrino mass hierarchy region. We highlight the main challenges and identify priorities for an R&D program addressing them.Comment: 22 pages, 15 figures, submitted to EPJ

    Search for Neutrinoless Double-Beta Decay of 130^{130}Te with CUORE-0

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    We report the results of a search for neutrinoless double-beta decay in a 9.8~kg\cdotyr exposure of 130^{130}Te using a bolometric detector array, CUORE-0. The characteristic detector energy resolution and background level in the region of interest are 5.1±0.3 keV5.1\pm 0.3{\rm~keV} FWHM and 0.058±0.004(stat.)±0.002(syst.)0.058 \pm 0.004\,(\mathrm{stat.})\pm 0.002\,(\mathrm{syst.})~counts/(keV\cdotkg\cdotyr), respectively. The median 90%~C.L. lower-limit sensitivity of the experiment is 2.9×1024 yr2.9\times 10^{24}~{\rm yr} and surpasses the sensitivity of previous searches. We find no evidence for neutrinoless double-beta decay of 130^{130}Te and place a Bayesian lower bound on the decay half-life, T1/20ν>T^{0\nu}_{1/2}>~2.7×1024 yr 2.7\times 10^{24}~{\rm yr} at 90%~C.L. Combining CUORE-0 data with the 19.75~kg\cdotyr exposure of 130^{130}Te from the Cuoricino experiment we obtain T1/20ν>4.0×1024 yrT^{0\nu}_{1/2} > 4.0\times 10^{24}~\mathrm{yr} at 90%~C.L.~(Bayesian), the most stringent limit to date on this half-life. Using a range of nuclear matrix element estimates we interpret this as a limit on the effective Majorana neutrino mass, mββ<270m_{\beta\beta}< 270 -- 760 meV760~\mathrm{meV}.Comment: 6 pages, 5 figures, updated version as published in PR
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