1,520 research outputs found

    NMR studies of two unusual f-electron metals

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    We present the results of nuclear magnetic resonance (NMR) studies down to very low temperatures for two U compounds, UCu3.5Pd1.5 and U0.8Y0.2Pd3, where the conduction electrons experience strong interactions and for which the temperature dependences of the thermal and transport properties do not obey the expectations of a simple Fermi-liquid model. Also the temperature and field dependences of the nuclear magnetization recovery of UCu3.5Pd1.5 in Cu nuclear quadrupole resonance show unusual features that cannot be reconciled with common expectations for a simple metal, but they are well accounted for by the Kondo disorder model. For U0.8Y0.2Pd3, our Y NMR results indicate a distribution of internal static magnetic fields at the Y sites and a small temperature-dependent enhancement of the spin-lattice relaxation rateT 1 − with respect to YPd3. The NMR spectra are consistent with the presence of very small frozen U moments, but the temperature dependence of the spin-lattice relaxation rate indicates a more complicated situatio

    Nutritional status, yield and composition of peach fruit subjected to the application of organic compost.

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    The purpose of this study was to evaluate the nutritional state, yield and composition of peaches on peach trees subjected to the application of organic compost to the soil. This experiment was conducted during the 2008 and 2009 cropping season in an orchard containing Chimarrita cultivars grafted onto Capdeboscq rootstocks and Haplumbrept soils in the municipality of Farroupilha (Rio Grande do Sul State), Brazil. The treatments included 0, 9, 18, 36, 72 and 144 liters of organic compost per plant-1 year-1. The total nutrient contents in the leaves, yield components, yields per plant and hectare and compositions of the fruits were evaluated in 2008 and 2009 soon after harvest and after 30 days of storage. The application of organic compost to the soil increased the yield components and the yields per plant and hectare in the two treatments with the highest compost additions, which indicated that the addition of 72 L of compost per plant-1 is ideal economically. The organic compost had little effect on the composition of the peach fruit after harvest and after 30 days of storage. Keywords: mineral nutrition, organic waste, Prunus persica. Estado nutricional, produção e composição de frutos de pessegueiros submetidos à aplicação de composto orgânico O objetivo do trabalho foi avaliar o estado nutricional, produção e composição de pêssegos em pessegueiros submetidos à aplicação de composto orgânico no solo. O experimento foi conduzido, na safra 2008 e 2009, em um pomar da cultivar Chimarrita, enxertada sobre o porta-enxerto Capdeboscq e cultivadas em um solo Cambissolo Húmico, no município de Farroupilha (Estado do Rio Grande do Sul). Os tratamentos foram 0, 9, 18, 36, 72 e 144 litros de composto orgânico por planta-1 ano-1. Avaliou-se o teor de nutrientes totais nas folhas, componentes de produção, produção por planta e hectare e a composição dos frutos em 2008 e 2009, logo depois da colheita e 30 dias após armazenamento. A aplicação de composto orgânico no solo, aumenta os valores de componentes de produção e a produção de pêssego por planta e hectare, nas duas maiores quantidades de composto fornecidas, o que economicamente indica a melhor dose de 72 L de composto por planta-1. A adição de composto orgânico na superfície do solo não afeta o estado nutricional e pouco afeta a composição dos pêssegos após a colheita e depois de 30 dias do armazenamento. Palavras-chave: nutrição mineral, resíduos orgânicos, Prunus persica

    Anomalous NMR Spin-Lattice Relaxation in SrB_{6} and Ca_{1-x}La_{x}B_{6}

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    We report the results of {11}B nuclear magnetic resonance (NMR) measurements of SrB_{6} and Ca_{0.995}La_{0.05}B_{6} below room temperature. Although the electrical resistivities of these two materials differ substantially, their {11}B-NMR responses exhibit some strikingly common features. Both materials exhibit ferromagnetic order, but their {11}B-NMR spectra reveal very small hyperfine fields at the Boron sites. The spin lattice relaxation T_{1}^{-1} varies considerably with external field but changes with temperature only below a few K. We discuss these unusual results by considering various different scenarios for the electronic structure of these materials.Comment: Accepted for publication in Phys. Rev. B Rapid communication, 4 pages, 3 figures. This manuscript replaces an earlier version and includes some minor changes in the text and in Fig.

    Colonização micorrízica e crescimento da videira (Vitis vinifera, Porta-Enxerto P1103) em solo com alto teor de cobre.

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    A aplicação de fungicidas cúpricos em vinhedos aumenta o teor de Cu no solo, potencializando a toxidez para a videira. Entretanto, tem sido relatado que os fungos micorrízicos arbusculares (FMA) podem propiciar efeito protetor às plantas em solos contendo excesso de metais pesados. O trabalho objetivou avaliar a colonização micorrízica e o crescimento da videira (porta-enxerto P1103) em solo contendo elevados teores de Cu. Avaliou-se seis tratamentos de inoculação com FMA (Dentiscutata heterogama, Gigaspora gigantea, Acaulospora morrowiae, A. colombiana, Rhizophagus clarus e R. irregularis), além de um não inoculado. Verificou-se que a colonização micorrízica da videira foi elevada (média de 33%), mesmo em solo contendo excesso de Cu. A inoculação dos isolados de FMA testados pouco influenciou o crescimento da videira, mas a inoculação com R. irregulares e R. clarus beneficiou a produção de massa seca das raízes das mudas.Resumo expandido

    Acúmulo de fósforo em solos cultivados com videiras na região da Campanha Gaúcha.

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    O presente trabalho teve como objetivo avaliar o acúmulo de frações de P em solos cultivados com videiras e com histórico de aplicação de fertilizantes fosfatados na região da Campanha Gaúcha do RS.bitstream/item/73780/1/Comunicado-Tecnico-131.pd

    Cognitive-behavioural treatment for subacute and chronic neck pain

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    BACKGROUND: Although research on non-surgical treatments for neck pain (NP) is progressing, there remains uncertainty about the efficacy of cognitive-behavioural therapy (CBT) for this population. Addressing cognitive and behavioural factors might reduce the clinical burden and the costs of NP in society.OBJECTIVES: To assess the effects of CBT among individuals with subacute and chronic NP. Specifically, the following comparisons were investigated: (1) cognitive-behavioural therapy versus placebo, no treatment, or waiting list controls; (2) cognitive-behavioural therapy versus other types of interventions; (3) cognitive-behavioural therapy in addition to another intervention (e.g. physiotherapy) versus the other intervention alone.SEARCH METHODS: We searched CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO, SCOPUS, Web of Science, and PubMed, as well as ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform up to November 2014. Reference lists and citations of identified trials and relevant systematic reviews were screened.SELECTION CRITERIA: We included randomised controlled trials that assessed the use of CBT in adults with subacute and chronic NP.DATA COLLECTION AND ANALYSIS: Two review authors independently assessed the risk of bias in each study and extracted the data. If sufficient homogeneity existed among studies in the pre-defined comparisons, a meta-analysis was performed. We determined the quality of the evidence for each comparison with the GRADE approach.MAIN RESULTS: We included 10 randomised trials (836 participants) in this review. Four trials (40%) had low risk of bias, the remaining 60% of trials had a high risk of bias.The quality of the evidence for the effects of CBT on patients with chronic NP was from very low to moderate. There was low quality evidence that CBT was better than no treatment for improving pain (standard mean difference (SMD) -0.58, 95% confidence interval (CI) -1.01 to -0.16), disability (SMD -0.61, 95% CI -1.21 to -0.01), and quality of life (SMD -0.93, 95% CI -1.54 to -0.31) at short-term follow-up, while there was from very low to low quality evidence of no effect on various psychological indicators at short-term follow-up. Both at short- and intermediate-term follow-up, CBT did not affect pain (SMD -0.06, 95% CI -0.33 to 0.21, low quality, at short-term follow-up; MD -0.89, 95% CI -2.73 to 0.94, low quality, at intermediate-term follow-up) or disability (SMD -0.10, 95% CI -0.40 to 0.20, moderate quality, at short-term follow-up; SMD -0.24, 95% CI-0.54 to 0.07, moderate quality, at intermediate-term follow-up) compared to other types of interventions. There was moderate quality evidence that CBT was better than other interventions for improving kinesiophobia at intermediate-term follow-up (SMD -0.39, 95% CI -0.69 to -0.08, I(2) = 0%). Finally, there was very low quality evidence that CBT in addition to another intervention did not differ from the other intervention alone in terms of effect on pain (SMD -0.36, 95% CI -0.73 to 0.02) and disability (SMD -0.10, 95% CI -0.56 to 0.36) at short-term follow-up.For patients with subacute NP, there was low quality evidence that CBT was better than other interventions at reducing pain at short-term follow-up (SMD -0.24, 95% CI -0.48 to 0.00), while no difference was found in terms of effect on disability (SMD -0.12, 95% CI -0.36 to 0.12) and kinesiophobia.None of the included studies reported on adverse effects.AUTHORS' CONCLUSIONS: With regard to chronic neck pain, CBT was found to be statistically significantly more effective for short-term pain reduction only when compared to no treatment, but these effects could not be considered clinically meaningful. When comparing both CBT to other types of interventions and CBT in addition to another intervention to the other intervention alone, no differences were found. For patients with subacute NP, CBT was significantly better than other types of interventions at reducing pain at short-term follow-up, while no difference was found for disability and kinesiophobia. Further research is recommended to investigate the long-term benefits and risks of CBT including for the different subgroups of subjects with N

    Role of [18F]FDG PET/CT in the management of G1 gastro-entero-pancreatic neuroendocrine tumors

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    Purpose: Since the role of [18F]FDG PET/CT in low-grade gastroenteropancreatic (GEP) neuroendocrine neoplasia (NET) is not well established, this study was aimed to evaluate the role of [18F]FDG PET/CT in grade 1 (G1) GEP-NETs. Methods: This is a retrospective study including patients with G1 GEP-NETs who underwent [18F]FDG PET/CT. Results: 55 patients were evaluated, including 24 (43.6%) with pancreatic NETs and 31 (56.4%) with gastrointestinal NETs. At the time of diagnosis, 28 (51%) patients had metastatic disease, and 50 (91%) patients were positive by 68-Ga sstr PET/CT. Overall, 27 patients (49%) had positive findings on [18F]FDG PET/CT. Following [18F]FDG PET/CT, therapeutic management was modified in 29 (52.7%) patients. Progression-free survival was longer in patients with negative [18F]FDG PET/CT compared with positive [18F]FDG PET/CT (median PFS was not reached and 24 months, respectively, p = 0.04). This significance was particularly evident in the pancreatic group (p = 0.008). Conclusions: Despite having low proliferative activity, approximately half of GEP-NETs G1 showed positive [18F]FDG PET/CT, with a corresponding negative impact on patients’ clinical outcomes. These data are in favor of a more “open” attitude toward the potential use of [18F]FDG PET/CT in the diagnostic work-up of G1 GEP-NETs, which may be used in selected cases to detect those at higher risk for an unfavorable disease course
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