757 research outputs found

    Selectivity of metribuzin in postemergence of culture of carrot

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    A citação dos autores está incorreto.The initial slow growth and short stature of carrot can allow that weeds settle in crop areas, requiring the management of these plants for productivity not to decrease. Nevertheless, weeds control has been difficult because there are few herbicides available for weeds control in postemergence of carrots. Two experiments in the field were carried out to evaluate selectivity of metribuzin applied in postemergence of carrots. A experimental randomized block design was utilized with four repetitions. Treatments consisted of metribuzin doses (0, 144, 288, 432, 576, 720, 960 and 1,200 g ha-1), applied in postemergence of carrots of the Nantes variety. Roots productivity was evaluated and percentage of commercial roots and no-commercial roots was calculated. Metribuzin has not caused visual symptoms of intoxication in carrots. Doses lower than 432 g ha-1 of metribuzin do not reduce the total productivity of roots, independent of the application period. Any doses of metribuzin changed the percentage of commercial and noncommercial roots. It is concluded that metribuzin is selective for carrots of the Nantes variety in postemergence applications at doses of 432 g ha-1.O lento crescimento inicial da cenoura favorece o estabelecimento de plantas daninhas nas áreas de cultivo, sendo necessário o manejo dessas plantas para que não ocorra redução da produtividade. Todavia, o controle tem sido dificultado por existirem poucas opções de herbicidas para o controle de plantas daninhas em pós-emergência da cultura. Dois experimentos de campo foram realizados para avaliar a seletividade do metribuzin aplicado em pós-emergência da cenoura, em dois diferentes períodos de cultivo (inverno e inverno-verão). O delineamento experimental foi o de blocos casualizados com quatro repetições. Os tratamentos corresponderam à aplicação de 0, 144, 288, 432, 576, 720, 960 e 1.200 g ha-1 do metribuzin na cultura da cenoura, cultivar Nantes. Foram avaliadas a produtividade total de raízes e a porcentagem de raízes comerciais e não comerciais. A produtividade total de raízes de cenoura não foi alterada pela aplicação de metribuzin até a dose de 432 g ha-1, independentemente da época de cultivo. A porcentagem de cenouras comercializáveis e descartáveis não foi alterada pelas doses do herbicida. Conclui-se que o metribuzin é seletivo para aplicação em pós-emergência da cenoura, cultivar Nantes, até a dose de 432 g ha-1

    Dynamics of an Intruder in Dense Granular Fluids

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    We investigate the dynamics of an intruder pulled by a constant force in a dense two-dimensional granular fluid by means of event-driven molecular dynamics simulations. In a first step, we show how a propagating momentum front develops and compactifies the system when reflected by the boundaries. To be closer to recent experiments \cite{candelier2010journey,candelier2009creep}, we then add a frictional force acting on each particle, proportional to the particle's velocity. We show how to implement frictional motion in an event-driven simulation. This allows us to carry out extensive numerical simulations aiming at the dependence of the intruder's velocity on packing fraction and pulling force. We identify a linear relation for small and a nonlinear regime for high pulling forces and investigate the dependence of these regimes on granular temperature

    Measuring Black Hole Spin using X-ray Reflection Spectroscopy

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    I review the current status of X-ray reflection (a.k.a. broad iron line) based black hole spin measurements. This is a powerful technique that allows us to measure robust black hole spins across the mass range, from the stellar-mass black holes in X-ray binaries to the supermassive black holes in active galactic nuclei. After describing the basic assumptions of this approach, I lay out the detailed methodology focusing on "best practices" that have been found necessary to obtain robust results. Reflecting my own biases, this review is slanted towards a discussion of supermassive black hole (SMBH) spin in active galactic nuclei (AGN). Pulling together all of the available XMM-Newton and Suzaku results from the literature that satisfy objective quality control criteria, it is clear that a large fraction of SMBHs are rapidly-spinning, although there are tentative hints of a more slowly spinning population at high (M>5*10^7Msun) and low (M<2*10^6Msun) mass. I also engage in a brief review of the spins of stellar-mass black holes in X-ray binaries. In general, reflection-based and continuum-fitting based spin measures are in agreement, although there remain two objects (GROJ1655-40 and 4U1543-475) for which that is not true. I end this review by discussing the exciting frontier of relativistic reverberation, particularly the discovery of broad iron line reverberation in XMM-Newton data for the Seyfert galaxies NGC4151, NGC7314 and MCG-5-23-16. As well as confirming the basic paradigm of relativistic disk reflection, this detection of reverberation demonstrates that future large-area X-ray observatories such as LOFT will make tremendous progress in studies of strong gravity using relativistic reverberation in AGN.Comment: 19 pages. To appear in proceedings of the ISSI-Bern workshop on "The Physics of Accretion onto Black Holes" (8-12 Oct 2012). Revised version adds a missing source to Table 1 and Fig.6 (IRAS13224-3809) and corrects the referencing of the discovery of soft lags in 1H0707-495 (which were in fact first reported in Fabian et al. 2009

    Proteins and their peptide motifs in acellular apatite mineralization of scaffolds for tissue engineering

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    Many proteins in the inorganic=organic matrix of bone induce or modulate or inhibit mineralization of apatite in vivo. Many attempts have been made to mimic and understand this mechanism as part of bone formation, and ectopic mineralization and control thereof. Many attempts have also been made to use such proteins or protein fragments to harness their potential for improved mineralization. Such proteins and peptide motifs have also been the inspiration for attempts of making mimics of their structures and motifs using chemical or biological synthesis. The aim of this review is to highlight how proteins and (poly)peptides themselves impact mineralization in the human body, and how those could be used and have been used for improving apatite mineralization, for example, on or in materials that by themselves do not induce apatite mineralization but otherwise have interesting properties for use as bone tissue engineering scaffolds.J. Benesch wishes to acknowledge the financial support from FCT, postdoctoral fellowship scholarship SFRH/BPD/17584/2004. This work was carried out under the scope of the European Union NoE EXPERTISSUES (NMP3-CT-2004500283) and partially funded by the European Union FP6 STREP Project HIPPOCRATES (NMP3-CT-2003-505758) and FCT project ProteoLight (PTDC/FIS/68517/2006)

    Integration of miRNA and mRNA expression profles reveals microRNA-regulated networks during muscle wasting in cardiac cachexia

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    Cardiac cachexia (CC) is a common complication of heart failure (HF) associated with muscle wasting and poor patient prognosis. Although different mechanisms have been proposed to explain muscle wasting during CC, its pathogenesis is still not understood. Here, we described an integrative analysis between miRNA and mRNA expression profiles of muscle wasting during CC. Global gene expression profiling identified 1,281 genes and 19 miRNAs differentially expressed in muscle wasting during CC. Several of these deregulated genes are known or putative targets of the altered miRNAs, including miR-29a-3p, miR-29b-3p, miR-210-5p, miR-214, and miR-489. Gene ontology analysis on integrative mRNA/miRNA expression profiling data revealed miRNA interactions affecting genes that regulate extra-cellular matrix (ECM) organization, proteasome protein degradation, citric acid cycle and respiratory electron transport. We further identified 11 miRNAs, including miR-29a-3p and miR-29b-3p, which target 21 transcripts encoding the collagen proteins related to ECM organization. Integrative miRNA and mRNA global expression data allowed us to identify miRNA target genes involved in skeletal muscle wasting in CC. Our functional experiments in C2C12 cells confirmed that miR-29b down-regulates collagen genes and contributes to muscle cell atrophy. Collectively, our results suggest that key ECM-associated miRNAs and their target genes may contribute to CC in HF

    Expanding indication of padeliporfin (WST11) vascular-targeted photodynamic therapy: results of prostate cancer Latin-American multicenter study

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    OBJECTIVES: To explore the proportion of patients with higher risk localized prostate cancer (PCa) that would become safely biopsy negative 12 months after non-thermal focal therapy with padeliporfin vascular-targeted photodynamic therapy (VTP). METHODS: Multicenter study in a scenario of prostate-specific antigen (PSA) ≤20ng/ml and variable PCa target volumes Gleason pattern 3 or low-volume secondary Gleason pattern 4, all patients received VTP, consisting of intravenous 4mg/kg padeliporfin activated by light-diffusing fibers in the prostate. The prostate was biopsied at baseline, months 6 and 12, PSA, patient-reported functional outcomes and quality of life (QoL) questionnaires were recorded at baseline, months 3, 6, and 12 and adverse events (AE) throughout the study. RESULTS: In the intention-to-treat population (n=81), the proportion of patients with negative biopsies at month 12 was 74% (60/81 patients; 95% CI: 63.1%,83.2%). In the per-protocol population, the proportion was 79% (58/73 patients; 95% CI: 68.4%,88.0%). Questionnaire results indicated a slight improvement in urinary function and limited deterioration in sexual function. No difference in QoL was observed over time. A total of 42/81 (52%) patients reported mild or moderate and 4 of 81 (4.9%) experienced serious AE, all resolved without sequelae. No phototoxicity, cardiovascular event, fistula or prolonged urinary incontinence, secondary cancer or death was reported. CONCLUSIONS: Results support the efficacy, safety, and QoL associated with padeliporfin focal treatment for low/intermediate risk localized PCa

    Lentinus crinitus basidiocarp stipe and pileus: chemical composition, cytotoxicity and antioxidant activity

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    Lentinus crinitus is a wild fungus, which produces mushrooms consumed by some Amazonian Indians. Besides, it is recognized for its diverse biological activities and biotechnological applications. However, there are few reports with limited information on basidiocarp chemical composition and cytotoxicity. Our study determined and evaluated the chemical composition, cytotoxicity, and antioxidant activity of L. crinitus pileus and stipe separately. Chromatographic methods were used to evaluate basidiocarp chemical composition. Cytotoxicity was verified using a cell culture from porcine liver and against a panel of human tumor cells from different models. Antioxidant activity was assessed by different in vitro methods. The pileus had higher levels of protein, ash, tocopherols, and organic acids, mainly malic acid, than the stipe. The stipe revealed higher contents of carbohydrates, energy, soluble sugars, and phenolic acids, mostly p-hydroxybenzoic acid. L. crinitus basidiocarp has mainly trehalose as soluble sugar, and less than 1% fat being ~60% polyunsaturated fatty acids (mostly linoleic and oleic acids), and ~13% saturated fatty acids (mostly palmitic acid). L. crinitus revealed high antioxidant activity for most methods and no cytotoxic activity against tumor and non-tumor cells. L. crinitus basidiocarp can be considered a functional food with applicability in food, cosmetic, and pharmaceutical industries. Graphic abstract: [Figure not available: see fulltext.]This research was supported by Universidade Paranaense, UniCesumar, Polytechnic Institute of Bragança, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brazil (CAPES)—finance code 001—, Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), and Fundação Araucária. The authors are also grateful to the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020); to the national funding by FCT, P.I., through the institutional scientific employment program-contract for L. Barros contract.info:eu-repo/semantics/publishedVersio
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