Bases metodológicas para la evaluación, uso y gestión sostenible de los recursos agrarios. Aplicación a la cuenca de Santa Catalina (Argentina)

Los recursos agrarios que son utilizados por el hombre para obtener alimentos y generar bienes económicos son el clima, los suelos, los genotipos vegetales y animales mejorados y las tecnologías. La intensificación en el uso del recurso suelo ha conducido a un deterioro del mismo con disminución en los rendimientos afectando negativamente la rentabilidad de las empresas. Esta situación ha generado serios interrogantes sobre el principio de sostenibilidad de la producción agraria. El desarrollo económico - social del área Centro – Sur de la provincia de Córdoba (Argentina) está directamente vinculado con la producción agraria regional, pues constituye la actividad económica más importante. Actualmente, uno de los principales problemas para el desarrollo deriva de la rentabilidad negativa de las empresas agrarias por bajos rendimientos físicos, situación que conduce a quebrantos económicos con el consiguiente éxodo rural. En este trabajo se propone una metodología para evaluar el potencial productivo de los recursos agrarios de la cuenca Santa Catalina localizada en el Centro - Sur de la provincia de Córdoba, con el fin de optimizar el uso y gestión de dichos recursos bajo principios de máxima eficiencia ecológica y sostenibilidad. Se delimitaron quince unidades ecológicamente homogéneas, se estimó la producción potencial y la susceptibilidad a la degradación ambiental. La producción potencial supera entre un 300% a un 400% a la producción real para la gran mayoría de los productos agrarios y el área presenta un elevado deterioro por erosión hídrica. Se ha realizado un análisis de alternativas productivas viables y, mediante la evaluación multicriterio discreta, se propone una nueva estructura productiva de la cuenca, incrementando de tres a once las alternativas de producción. Se concluye que, mediante la evaluación cuantitativa de la capacidad productiva y de la degradación de los recursos naturales, es posible seleccionar alternativas productivas ecológicamente eficientes, sostenibles y tecnológicamente viables para estabilizar el deterioro ambiental e incrementar la producción física en las actuales condiciones socio - económicas del sector productivo regional

Identification guide for cephalopod paralarvae from the Mediterranean Sea

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Asymptotic behaviour of Sobolev-type orthogonal polynomials on a rectifiable Jordan arc

22 pages, no figures.-- MSC2000 codes: Primary 42C05.MR#: MR1890494 (2002m:42023)Zbl#: Zbl 0991.42018Our object of study is the asymptotic behavior of the sequence of polynomials orthogonal with respect to the discrete Sobolev inner product $$\langle f, g \rangle = \int_{E} f(\xi) \overline{g(\xi)} \rho (\xi) \xi \xi f(Z) A g(Z)^H,$$ where $E$ is a rectifiable Jordan curve or arc in the complex plane $$f(Z) = (f(z_1), \ldots, f^{(l_1)}(z_1) , \ldots , f(z_m) , \ldots ,f^{(l_m)}(z_m)),$$ $A$ is an $M \times M$ Hermitian matrix, $M=l_{1} + \cdots + l_{m} + m$, $denotes the arc length measure,$\rho$is a nonnegative function on$E$, and$z_{i} \in \Omega$,$i=1,2,\ldots,m$, where$\Omega$is the exterior region to$E$.The work of the first author was supported by the Portuguese Ministry of Science and Technology, Fundação para a Ciência e Tecnología of Portugal under grant FMRH-BSAB-109-99 and by the Centro de Matemática da Universidade de Coimbra. The second author would also like to thank the Unidade de Investigação (Matemática e Aplicações) of the University of Aveiro for their support. The work of the second and third authors was supported by the Dirección General de Enseñanza Superior (DGES) of Spain under grant PB 96-0120-C03-01.Publicad

Biofilm formation in spent nuclear fuel pools and bioremediation of radioactive water

Microbiological studies of spent nuclear fuel pools at the Cofrentes Nuclear Power Plant (Valencia, Spain) were initiated to determine the microbial populations in the pools’ water. Biofilm formation at the nuclear power plant facilities and the potential use of those microbial populations in the bioremediation of radioactive water were also studied. Biofilm formation was analyzed by immersing different austenitic stainless steel coupons (UNS S30400, UNS S30466, UNS S31600), as well as balls of stainless steel (UNS S44200) and titanium (99.9%) in a spent nuclear fuel pool (under static and dynamic conditions) for 34 months. Epifluorescence microscopy and scanning electron microscopy revealed that biofilm formed on the samples, in spite of the radioactive and oligotrophic conditions of the water. Based on standard culture methods and sequencing of 16S rDNA fragments, 57 bacteria belonging to α-, β-, and γ-Proteobacteria, Firmicutes and Actinobacteridae were identified in the biofilms. The radioactivity of the biofilm was measured using γ-ray spectrometry, which revealed that biofilms were able to retain radionuclides, especially 60Co. Using metallic materials to decontaminate radioactive water could become a new approach for bioremediation. [Int Microbiol 2005 8(3):223-230

Bioavailability of orange juice (poly)phenols: the impact of short-term cessation of training by male endurance athletes

Background: Physical exercise has been reported to increase the bioavailability of citrus flavanones. Objective: To investigate the bioavailability of orange juice (OJ) (poly)phenols in endurance-trained men before and after cessation of training for 7 days. Design: Ten fit endurance-trained males, with a maximal oxygen consumption of 58.2 ± 5.3 mL/kg/min, followed a low (poly)phenol diet for 2 d before drinking 500 mL of OJ, containing 398 µmol of (poly)phenols of which 330 µmol were flavanones. After the volunteers stopped training for 7 days the feeding study was repeated. Urine samples were collected 12 h pre- and 24 h post-OJ orange consumption. Bioavailability was assessed by the quantitative analysis of urinary flavanone metabolites and (poly)phenol catabolites using HPLC-HR-MS. Results: While training, 0-24 h urinary excretion of flavanone metabolites, mainly hesperetin-3-O-glucuronide, hesperetin-3´-sulfate, naringenin-4´-O-glucuronide, naringenin-7-O-glucuronide, was equivalent to 4.2% of OJ flavanone intake. This increased significantly to 5.2% when OJ was consumed after the volunteers stopped training for 7 days. Overall, this trend, although not significant, was also observed with OJ-derived colonic catabolites which after supplementation in the trained state were excreted in amounts equivalent to 51% of intake compared to 59% after cessation of training. However, urinary excretion of three colonic catabolites of bacterial origin, most notably, 3-(3´-hydroxy-4´-methoxyphenyl)hydracrylic acid, did increase significantly when OJ was consumed post- compared to pre-cessation of training. Data were also obtained on inter-individual variations in flavanone bioavailability. Conclusion: A 7-day cessation of endurance training enhanced, rather than reduced, the bioavailability of OJ flavanones. The biological significance of these differences and, whether or not they extend to the bioavailability of other dietary (poly)phenols, remains to be determined. Hesperetin-3´-O-glucuronide and the colonic microbiota-derived catabolite 3-(3´-hydroxy-4´-methoxyphenyl)hydracrylic acid are key biomarkers of the consumption of hesperetin-O-glycoside-containing OJ and other citrus products

Coherent pairs of linear functionals on the unit circle

In this paper we extend the concept of coherent pairs of measures from the real line to Jordan arcs and curves. [...]info:eu-repo/semantics/publishedVersio

A potential immune escape mechanism by melanoma cells through the activation of chemokine-induced T cell death

AbstractThe immune system attempts to prevent or limit tumor growth, yet efforts to induce responses to tumors yield minimal results, rendering tumors virtually invisible to the immune system [1]. Several mechanisms may account for this subversion, including the triggering of tolerance to tumor antigens [2, 3], TGF-α or IL-10 production, downregulation of MHC molecules, or upregulation of FasL expression [4, 5]. Melanoma cells may in some instances use FasL expression to protect themselves against tumor-infiltrating lymphocytes (TIL) [4, 5]. Here, we show another, chemokine-dependent mechanism by which melanoma tumor cells shield themselves from immune reactions. Melanoma-inducible CCL5 (RANTES) production by infiltrating CD8 cells activates an apoptotic pathway in TIL involving cytochrome c release into the cytosol and activation of caspase-9 and -3. This process, triggered by CCL5 binding to CCR5, is not mediated by TNFα, Fas, or caspase-8. The effect is not unique to CCL5, as other CCR5 ligands such as CCL3 (MIP-1α) and CCL4 (MIP-1β) also trigger TIL cell death, nor is it limited to melanoma cells, as it also operates in activated primary T lymphocytes. The model assigns a role to the CXC chemokine CXCL12 (SDF-1α) in this process, as this melanoma cell-produced chemokine upregulates CCL5 production by TIL, initiating TIL cell death

Lax-type pairs in the theory of bivariate orthogonal polynomials

Sequences of bivariate orthogonal polynomials written as vector polynomials of increasing size satisfy a couple of three term relations with matrix coefficients. In this work, introducing a time-dependent parameter, we analyse a Lax-type pair system for the coefficients of the three term relations. We also deduce several characterizations relating the Lax-type pair, the shape of the weight, Stieltjes function, moments, a differential equation for the weight, and the bidimensional Toda-type systems

Natural bioactive compounds from winery by-products as health promoters: A review

The relevance of food composition for human health has increased consumers’ interest in the consumption of fruits and vegetables, as well as foods enriched in bioactive compounds and nutraceuticals. This fact has led to a growing attention of suppliers on reuse of agro-industrial wastes rich in healthy plant ingredients. On this matter, grape has been pointed out as a rich source of bioactive compounds. Currently, up to 210 million tons of grapes (Vitis vinifera L.) are produced annually, being the 15% of the produced grapes addressed to the wine-making industry. This socio-economic activity generates a large amount of solid waste (up to 30%, w/w of the material used). Winery wastes include biodegradable solids namely stems, skins, and seeds. Bioactive compounds from winery by-products have disclosed interesting health promoting activities both in vitro and in vivo. This is a comprehensive review on the phytochemicals present in winery by-products, extraction techniques, industrial uses, and biological activities demonstrated by their bioactive compounds concerning potential for human health. © 2014 by the authors; licensee MDPI, Basel, Switzerland.This work was supported by national funds from FCT-Portuguese Foundation for Science and Technology, under the projects PEst-OE/AGR/UI4033/2014 and Project INNOFOOD-INNovation in the FOOD sector through the valorization of food and agro-food by-products-NORTE-07-0124-FEDER-0000029, financed by the North Portugal Regional Operational Programme (ON.2–O Novo Norte) under the National Strategic Reference Framework (QREN), through the European Regional Development Fund (FEDER). The authors also express their gratitude to the Spanish Ministry of Economy and Competitiveness for the funding through the CICYT project AGL2011-23690, and the CYTED Program (Ref. 112RT0460) CORNUCOPIA Thematic Network [192]. We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI)Peer Reviewe

FtsZ of filamentous, heterocyst-forming cyanobacteria has a conserved N-Terminal peptide required for normal FtsZ polymerization and cell division

Filamentous cyanobacteria grow by intercalary cell division, which should involve distinct steps compared to those producing separate daughter cells. The N-terminal region of FtsZ is highly conserved in the clade of filamentous cyanobacteria capable of cell differentiation. A derivative of the model strain Anabaena sp. PCC 7120 expressing only an FtsZ lacking the amino acids 2-51 of the N-terminal peptide (1N-FtsZ) could not be segregated. Strain CSL110 expresses both 1N-FtsZ, from the endogenous ftsZ gene promoter, and the native FtsZ from a synthetic regulated promoter. Under conditions of 1N-FtsZ predominance, cells of strain CSL110 progressively enlarge, reflecting reduced cell division, and show instances of asymmetric cell division and aberrant Z-structures notably differing from the Z-ring formed by FtsZ in the wild type. In bacterial 2-hybrid assays FtsZ interacted with 1N-FtsZ. However, 1N-FtsZ-GFP appeared impaired for incorporation into Z-rings when expressed together with FtsZ. FtsZ, but not 1N-FtsZ, interacted with the essential protein SepF. Both FtsZ and 1N-FtsZ polymerize in vitro exhibiting comparable GTPase activities. However, filaments of FtsZ show a distinct curling forming toroids, whereas 1N-FtsZ form thick bundles of straight filaments. Thus, the N-terminal FtsZ sequence appears to contribute to a distinct FtsZ polymerization mode that is essential for cell division and division plane location in Anabaena.Agencia Estatal de Investigación BFU2013-44686-P BFU2016-77097-