1,360 research outputs found

    El Proceso de la Conceptualización en la Teoría del Conocimiento (BREVE VISION DEL CONCEPTO)

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    El concepto de psique es aplicable tanto al hombre como os animales, pero el concepto de conciencia es propio solamente de hombre

    Wood Anatomical Responses of European Beech to Elevation, Land Use Change, and Climate Variability in the Central Apennines, Italy.

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    European beech (Fagus sylvatica L.) is a widespread and economically important temperate tree species in Europe. The warmer temperatures and severe drought events expected in the future, especially in Mediterranean areas, could affect the vitality and productivity of beech stands that have been intensively used in these areas in the past. Here, we aim to assess the wood anatomical responses of beech to environmental variability and silvicultural practices by investigating three beech stands along an elevational gradient (1,200 to 1,950 m a.s.l.) in the Apennines (Italy). Therefore, we quantified several anatomical traits of the xylem vessels related to tree hydraulics from five trees per stand and investigated variability between and within tree rings. Our results suggest generally limited trait plasticity, with higher plasticity of mean vessel lumen area and theoretical hydraulic conductivity, while maximum vessel size and mean hydraulic diameter were less plastic, likely because of the stronger determination by tree height. High-elevation trees were hydraulically more limited than trees at a mid and lower elevation as indicated by the more conservative anatomical configuration, i.e., comparatively smaller vessels and a 50% tighter trait coordination. Cessation of coppicing resulted in a hydraulically safer anatomy with comparatively smaller vessels at the most intensively used site (1,200 m), triggered by increased water demand due to an increase in canopy density, and thus, an increase in stand transpiration. Furthermore, maximum vessel size at the beginning showed different climate sensitivity compared to the rest of the tree ring, while intra-ring anatomical profiles showed little difference between normal and the 5 years with the highest and lowest mean temperature and precipitation. Overall, this study highlights the challenges to separate the externally induced medium- to longer-term responses from ontogenetically determined patterns. We, therefore, call for more comprehensive studies to further explore and verify the plasticity of wood anatomical traits in European beech in response to short- to long-term environmental fluctuations to gain a mechanistic understanding useful for sustainable forest ecosystems

    Microstructural Study of a Zn-Ni Alloy Prepared by Ball Milling Using Two Different Devices

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    Metallic zinc (Zn) has ben extensively used as protective coating of iron and steel for decades, but problems related with its high permeability has reduced its application. It was found that the corrosion resistance of zinc in form of alloys is increased by adding some transition metals. Recently, the Zn-Ni system is under research as an efficient alternative as anticorrosion coating for metals. Zn-Ni is mostly prepared by electroplating or thermal spray technologies, but there are some problems like: (i) fluctuation of Zn-Ni contents, (ii) the pollution caused by plating solutions and (iii) irregular thickness of the coating. The mechanical alloying (MA) technique can be used to fulfill the above issues because this route facilitates the synthesis of homogeneous materials from powder mixtures . Also, MA is frequently employed for the preparation of new materials based on mechanochemical reactions performed at room temperature, while avoiding the conventional ingot metallurgy [3]. This work deals with the preparation and study of a Zn-Ni alloy prepared by MA using two types of milling devices: a planetary which works manly through abrasion and impact of grinding balls and the Spex which works through the high-energy impact of balls. Zn-Ni was prepared from pure Ni and Zn powders, the equiatomic compositions were weighed and milled for 4 hours followed by sintering at 357°C during 1h

    IFA and PIFA Size Reduction by Using a Stub Loading

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    A proposed technique for size reduction of a conventional inverted-F antenna (IFA) and a planar inverted-F antenna (PIFA) by employing a reactive load generated by a short-circuited stub is presented. The reduction factor of both antennas is around 30%, and the main parameters of the devices are preserved, including a fractional bandwidth of 4% and a gain of −2 dB. Both antennas operate around 1.5 GHz

    Male cytogenetic evaluation prior to assisted reproduction procedures performed in Mar del Plata, Argentina

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    Objective: This paper aimed to estimate the frequency ofoccurrence and the types of chromosomal abnormalitiesfound in 141 infertile men with abnormal semen parameters.Methods: the frequency and type of chromosomal abnormalitieswere determined with male mitotic karyotypeanalysis from peripheral blood through chromosome bandingtechniques before assisted reproduction procedures.Results: In this series of 141 infertile men, 19 (13%) hadchromosomal anomalies and 35 (25%) had polymorphicvariants. The main chromosome abnormalities were reciprocaltranslocations and marker chromosomes in mosaic.Conclusions: These results stress the relevance of cytogeneticstudies for infertile males as a diagnostic tool anda valuable input in genetic counseling.Fil: Poli, María Noelia. Asociacion de Genetica Humana; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lopez Miranda, Lucía A.. Asociacion de Genetica Humana; ArgentinaFil: Gil, Eduardo Daniel. Asociacion de Genetica Humana; ArgentinaFil: Zanier, Germán Justo. Asociacion de Genetica Humana; ArgentinaFil: Fernandez Iriarte, Pedro Jose. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología. Laboratorio de Genética; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Zanier, Justo Hector Mario. Asociacion de Genetica Humana; ArgentinaFil: Coco, Roberto. Fecunditas Instituto de Medicina Reproductiva; Argentin

    Does the casting mode influence microstructure, fracture and properties of different metal ceramic alloys?

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    The aim of the present study was to evaluate the tensile strength, elongation, microhardness, microstructure and fracture pattern of various metal ceramic alloys cast under different casting conditions. Two Ni-Cr alloys, Co-Cr and Pd-Ag were used. The casting conditions were as follows: electromagnetic induction under argon atmosphere, vacuum, using blowtorch without atmosphere control. For each condition, 16 specimens, each measuring 25 mm long and 2.5 mm in diameter, were obtained. Ultimate tensile strength (UTS) and elongation (EL) tests were performed using a Kratos machine. Vickers Microhardness (VM), fracture mode and microstructure were analyzed by SEM. UTS, EL and VM data were statistically analyzed using ANOVA. For UTS, alloy composition had a direct influence on casting condition of alloys (Wiron 99 and Remanium CD), with higher values shown when cast with Flame/Air (p < 0.05). The factors "alloy" and "casting condition" influenced the EL and VM results, generally presenting opposite results, i.e., alloy with high elongation value had lower hardness (Wiron 99), and casting condition with the lowest EL values had the highest VM values (blowtorch). Both factors had significant influence on the properties evaluated, and prosthetic laboratories should select the appropriate casting method for each alloy composition to obtain the desired property.CNPqCNPq [479369/2009-7]FAPEMAFAPEMA [01164/09, 617/2011

    Pancreas and islet transplantation in patients with diabetes mellitus

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    Pancreas and kidney transplants have specific indications, benefits and risks. The procedure has become more common and more often as long-term success has improved and risks have decreased. Compared with a patient being on dialysis, simultaneous pancreas-kidney transplant offers a distinct advantage when it comes to mortality, quality of life and diabetic complications. Since there can be a living-donor kidney transplant,, a possibly similar patient and graft survival by 10 years follow-up, this procedure should be considered. Pancreas after kidney transplants, when successful, can improve microvascular complications compared with kidney transplant alone, but immediate mortality may be higher. Solitary pancreas transplantation can improve the quality of life in selected patients, but it may also increase the immediate risk of mortality due to the complexity of the surgery and the risks of immunosupression. The results of Islet transplantation differ from the higher metabolic performance achieved by whole pancreas allotransplantation and its applicability is limited to selected adult diabetic patients.O transplante simultâneo de pâncreas/rim tem indicações específicas, riscos e benefícios. O procedimento, cada vez mais realizado, traz vantagens se comparado ao paciente em diálise, em relação à qualidade de vida, anos de vida ganhos e evolução das complicações crônicas. Se o paciente tiver a opção de realizar o transplante de rim com doador vivo, que apresenta sobrevida semelhante do enxerto e do paciente aos dez anos, o procedimento deverá ser considerado. O transplante de pâncreas após rim, quando efetivo, pode melhorar a evolução das complicações cardiovasculares, mas em contrapartida provoca maior mortalidade nos primeiros meses após a cirurgia. O transplante isolado de pâncreas também ocasiona a maior mortalidade pós-operatória, resultado da complexidade do procedimento e da imunossupressão. O transplante de ilhotas tem sua indicação para um seleto grupo de diabéticos com instabilidade glicêmica.Universidade Federal de São Paulo (UNIFESP) Departamento de Medicina Departamento de CirurgiaPontifícia Universidade Católica do Rio Grande do Sul Hospital São Lucas Serviço de NefrologiaUniversidade de São Paulo Núcleo de Terapia Celular e MolecularSistema de Saúde Centro de Pesquisa Médica Notre-Dame IntermédicaUSP Faculdade de Medicina Departamento de Clínica MédicaUniversidade Federal do Rio Grande do Sul Departamento de Medicina InternaHospital Israelita Albert Einstein Serviço de Transplante de PâncreasUNIFESP, Depto. de Medicina Depto. de CirurgiaSciEL

    El desarrollo municipal, factor estratégico en el posicionamiento de México en los escenarios políticos y sociales del siglo XXI

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    LA DEMOCRACIA COMO GOBERNABILIDAD IMPLICA, EN UN PRIMER MOMENTO, establecer una revisión periódica del papel interventor del Estado, por ser éste el principal factor de estabilidad y desarrollo democrático. En un segundo punto, de forma simultánea al estudio del papel del Estado en la conformación de un ambiente de estabilidad, crecimiento, desarrollo, orden y gobernabilidad, merece especial atención el papel y funciones cumplidas tradicionalmente por sus ámbitos de gobierno, como instancias que son fundamentales para la transición, democratización, liberalización y para la propia gobernabilidad

    Discovery of first-in-class reversible dual small molecule inhibitors against G9a and DNMTs in hematological malignancies

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    The indisputable role of epigenetics in cancer and the fact that epigenetic alterations can be reversed have favoured development of epigenetic drugs. In this study, we design and synthesize potent novel, selective and reversible chemical probes that simultaneously inhibit the G9a and DNMTs methyltransferase activity. In vitro treatment of haematological neoplasia (acute myeloid leukaemia-AML, acute lymphoblastic leukaemia-ALL and diffuse large B-cell lymphoma-DLBCL) with the lead compound CM-272, inhibits cell proliferation and promotes apoptosis, inducing interferon-stimulated genes and immunogenic cell death. CM-272 significantly prolongs survival of AML, ALL and DLBCL xenogeneic models. Our results represent the discovery of first-in-class dual inhibitors of G9a/DNMTs and establish this chemical series as a promising therapeutic tool for unmet needs in haematological tumours.We particularly acknowledge the Biobank of the University of Navarra for its collaboration. We thank Dr Edorta Martínez de Marigorta and Dr Francisco Palacios from Departamento de Química Orgánica I, Facultad de Farmacia, Universidad del Pais Vasco for 13C NMR determination and Angel Irigoyen Barrio and Dr Ana Romo Hualde, from University of Navarra, for HRMS determination. Dr. Irene de Miguel Turrullols from Small Molecule Discovery Platform, CIMA, University of Navarra is acknowledged for NMR data interpretation. This work was funded by grants from Instituto de Salud Carlos III (ISCIII) PI10/01691, PI13/01469, PI14/01867, PI10/2983, TRASCAN (EPICA), CIBERONC, cofinanciacion FEDER, RTICC RD12/0036/0068, Fundació La Marató de TV3 (20132130-31-32) and ‘Fundación Fuentes Dutor’. B.P. is supported by a Sara Borrell fellowship CD13/00340 and X.A. is a Marie Curie researcher under contract ‘LincMHeM-330598’.S
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