1,720,976 research outputs found
State-of-the-art of the Jatropha curcas productive chain: from sowing to biodiesel and by-products
No full textIn the forthcoming years, 1-2 million hectares of Jatropha curcas L. are expected to be annually planted, reaching 12.8 million hectares worldwide by 2015. This considerable expansion is due to its products and byproducts multiple uses and its amazing adaptability. J. curcas oil extracted by seeds is a promising renewable feedstock for biodiesel production and, together with the oil extraction by-products, it can be used as cooking/lighting fuel, bio-pesticide, organic fertilizer, combustible fuel, and for soap making. The capability to grow on poor quality soils not suitable for food crop makes J. curcas a possible solution of all the controversies related to biodiesel production. Furthermore, J. curcas contributes to mitigate environmental problems, such as marginal land or abandoned farmland reclamation. Nevertheless, J. curcas is not a “miracle tree”: i) the full potential of J. curcas is far from being achieved and its talents are still to be supported by scientific evidences; ii) J. curcas capabilities are not easily exploitable and applicable simultaneously; iii) its use is controversial and potentially unsustainable due to the current knowledge gaps about the impacts and potentials of J. curcas plantations. The aims of this review are to detail each phase of J. curcas productive chain from sowing to biodiesel and by-products, in order to logically organize the knowledge around J. curcas system, and to compare potentialities and criticalities of J. curcas, highlighting the agronomical, management, and environmental issues which should be still investigated
Gas exchange and antioxidants in Fraxinus excelsior trees with ozone visible injury and infused with the antioxidant EDU
No full textGravitational infusion of ethylenediurea (EDU) into trunks protected adult ash trees from foliar ozone injury and highlighted the mechanisms of protection
No full textProtection of ash (Fraxinus excelsior) trees from ozone injury by ethylenediurea (EDU): Roles of biochemical changes and decreased stomatal conductance in enhancement of growth
No full textTreatments with ethylenediurea (EDU) protect plants from ozone foliar injury, but the processes underlying this protection are poorly understood.
Adult ash trees (Fraxinus excelsior), with or without foliar ozone symptoms in previous years, were treated with EDU at 450 ppm
by gravitational trunk infusion in MayeSeptember 2005 (32.5 ppm h AOT40). At 30-day intervals, shoot growth, gas exchange, chlorophyll
a fluorescence, and water potential were determined. In September, several biochemical parameters were measured. The protective influence
of EDU was supported by enhancement in the number of leaflets. EDU did not contribute its nitrogen to leaf tissue as a fertiliser, as determined
from lack of difference in foliar N between treatments. Both biochemical (increase in ascorbate-peroxidase and ascorbic acid, and decrease in
apoplastic hydrogen peroxide) and biophysical (decrease in stomatal conductance) processes regulated EDU action. As total ascorbic acid
increased only in the asymptomatic trees, its role in alleviating O3 effects on leaf growth and visible injury is controversial
Vitamin D prevents pancreatic cancer-induced apoptosis signaling of inflammatory cells
Full text linkCombined approaches based on immunotherapy and drugs supporting immune effector cell function might increase treatment options for pancreatic ductal adenocarcinoma (PDAC), vitamin D being a suitable drug candidate. In this study, we evaluated whether treatment with the vitamin D analogue, calcipotriol, counterbalances PDAC induced and SMAD4-associated intracellular calcium [Ca2+]i alterations, cytokines release, immune effector function, and the intracellular signaling of peripheral blood mononuclear cells (PBMCs). Calcipotriol counteracted the [Ca2+]i depletion of PBMCs induced by SMAD4-expressing PDAC cells, which conditioned media augmented the number of calcium flows while reducing whole [Ca2+]i. While calcipotriol inhibited spontaneous and PDAC-induced tumor necrosis factor alpha (TNF-α) release by PBMC and reduced intracellular transforming growth factor beta (TGF-β), it did not counteract the lymphocytes proliferation induced in allogenic co-culture by PDAC-conditioned PBMCs. Calcipotriol mainly antagonized PDAC-induced apoptosis and partially restored PDAC-inhibited NF-κB signaling pathway. In conclusion, alterations induced by PDAC cells in the [Ca2+]i of immune cells can be partially reverted by calcipotriol treatment, which promotes inflammation and antagonizes PBMCs apoptosis. These effects, together with the dampening of intracellular TGF-β, might result in an overall anti-tumor effect, thus supporting the administration of vitamin D in PDAC patients
New diagnostic approaches for inflammatory bowel diseases
No full textInflammatory bowel diseases (IBD), that include ulcerative colitis (UC) and Crohn's disease (CD) are among the most serious and perplexing digestive diseases. Indeed, diagnosis is sometimes delayed due to the variability and subtlety of its initial manifestations, especially in CD. Since no gold standard is currently defined for the diagnosis and monitoring of IBD, a number of genomic, metabolomic and proteomic studies have tried to address this issue. After illustrating the traditional diagnostic approach (mainly fecal calprotectin), this Opinion Paper reports about the utility of some new biomarkers (micro-RNA, proteomic and metabolomic markers). In particular, the results of a study on fecal peptides are commented. After verifying that proteolytic degradation was clearly visible in fecal samples of a number of control (n=34) and patients with IBD (n=133), the matrix-assisted laser desorption ionization (MALDI) time of flight (TOF) mass spectrometry was used to evaluate peptides patterns of fecal samples, in a range from 1000 to 4000 Da. This cohort was used to derive an algorithm for IBD diagnosis. Diagnostic performances were then estimated using an additional validation cohort, including subjects with IBD (n=42) and without IBD (n= 28). Sensitivity was 54.8% (95%CI: 38.7%-70.2%) and specificity 96.4% (95%CI: 81.7%-99.9%) with a positive and a negative predictive value of 95.8% (95%CI: 76.7%-99.4%) and 58.7% (95%CI: 50.3-66.6%), respectively. In comparison, fecal calprotectin, achieved sensitivity and specificity of 78.6% (95%CI: 63.2%-89.7%) and 42.9% (95%CI: 24.5%-62.8%). In spite of the obtained good diagnostic performances, any candidate biomarker, once identified, should be carefully validated before being translated into clinical practice
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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