996 resultados para Ortega, Rafael (Ortega Gómez)


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O processamento mínimo permite a obtenção de produtos com qualidade, frescor e conveniência para o consumidor. O objetivo deste trabalho foi determinar os efeitos de tipos de corte e de temperaturas de armazenamento na conservação de produto minimamente processado de goiabas 'Kumagai' e 'Pedro Sato', associando-se goiabas de polpa branca e de polpa vermelha num único produto, como forma de torná-lo mais atraente e nutritivo. Os frutos foram minimamente processados em rodelas e fatias, acondicionados em bandejas de poliestireno expandido, recobertas com filme de PVC 17µm e armazenadas a 5ºC e 15ºC, durante 9 dias. As análises foram realizadas a cada 3 dias quanto às suas características físicas e químicas (firmeza do mesocarpo e da região placentária, cor da casca e da região placentária e teores de sólidos solúveis, acidez titulável e ácido ascórbico) e sensoriais (aparência). As temperaturas e os tipos de cortes não influenciaram nos conteúdos de ácido ascórbico, sólidos solúveis e acidez titulável. O corte tipo rodela manteve por mais tempo a firmeza do mesocarpo e da região placentária. A temperatura de 5ºC preservou a cor da casca, enquanto a de 15ºC e o corte tipo fatia implicaram maior escurecimento da polpa na região placentária. O produto minimamente processado mantido a 5ºC, bem como o corte em rodelas foram os preferidos pelos provadores

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A estimativa da área foliar por meio de curvas de regressão que empregam o produto do comprimento pela largura do limbo como variável independente, é uma prática comumente empregada na análise de crescimento vegetal. Entretanto, dependendo da natureza do material vegetal e das condições de cultivo, é possível a ocorrência de variações que afetam essa relação alométrica, o que implica a não universalidade de uma única curva de regressão. Devido a esse problema, o presente trabalho teve como objetivo realizar uma avaliação do efeito da irrigação e da ontogenia sobre a estimativa da área foliar da Hancornia speciosa, para testar a hipótese de que a irrigação afetaria tal relação alométrica. Verificou-se que os modelos de regressão obtidos para as plantas irrigadas e para as não irrigadas diferiram entre si, sendo que houve a necessidade da inclusão da área foliar específica no modelo de estimativa da área foliar das plantas não irrigadas. A não inclusão dessa variável no modelo de regressão acarretou uma diferença de estimativa que se incrementou com a redução da área foliar específica. Em folhas recém-expandidas de plantas irrigadas e não irrigadas, verificou-se diferença na área foliar específica devida à alteração na massa seca e não associada à largura dos tecidos foliares.

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Activity decreases, or deactivations, of midline and parietal cortical brain regions are routinely observed in human functional neuroimaging studies that compare periods of task-based cognitive performance with passive states, such as rest. It is now widely held that such task-induced deactivations index a highly organized"default-mode network" (DMN): a large-scale brain system whose discovery has had broad implications in the study of human brain function and behavior. In this work, we show that common task-induced deactivations from rest also occur outside of the DMN as a function of increased task demand. Fifty healthy adult subjects performed two distinct functional magnetic resonance imaging tasks that were designed to reliably map deactivations from a resting baseline. As primary findings, increases in task demand consistently modulated the regional anatomy of DMN deactivation. At high levels of task demand, robust deactivation was observed in non-DMN regions, most notably, the posterior insular cortex. Deactivation of this region was directly implicated in a performance-based analysis of experienced task difficulty. Together, these findings suggest that task-induced deactivations from rest are not limited to the DMN and extend to brain regions typically associated with integrative sensory and interoceptive processes.

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En la actualidad, los estereotipos de belleza impuestos en la sociedad han despertado un interés generalizado por la imagen corporal. Se espera de nosotros que tengamos un aspecto agradable acorde con los estándares estéticos. Esta presión social está potenciada por los medios de comunicación que se encargan de difundir el ideal de belleza en las sociedades contemporáneas. El rechazo social hacia la imagen corporal o la insatisfacción con la percepción del propio cuerpo pueden conducir a una baja autoestima, estigmatización social o problemas psicológicos. Las consecuencias de la sobrevaloración de la imagen corporal se extienden con la aparición de determinadas patologías o la necesidad de aplicación de determinados procedimientos que afectan a la apariencia física del individuo. Existen algunos procesos quirúrgicos que pueden implicar importantes modificaciones en la imagen corporal. Concretamente, las lesiones por quemaduras, las ostomías y las amputaciones suponen un impacto importante para la persona y pueden afectar de forma considerable en su bienestar psicosocial y en la calidad de vida. Producen grandes repercusiones en todas las dimensiones de la persona generando una gran angustia en ella debido a las dudas sobre cómo se verá afectada su vida diaria, surgiendo sentimientos de tristeza, depresión, cambios de humor o negación al cambio. Es importante que los profesionales sanitarios sean conscientes de las diferentes repercusiones que algunas intervenciones quirúrgicas pueden desencadenar en el paciente para poder desarrollar intervenciones adecuadas. Por este motivo, el presente trabajo pretende analizar las consecuencias derivadas de determinados procesos quirúrgicos y su relación con la imagen corporal.

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New material of the wasp family Maimetshidae (Apocrita) is presented from four Cretaceous amber de- posits- the Neocomian of Lebanon, the Early Albian of Spain, the latest Albian/earliest Cenomanian of France, and the Campanian of Canada. The new record from Canadian Cretaceous amber extends the temporal and paleogeographical range of the family. New material from France is assignable to Guyote- maimetsha enigmatica Perrichot et al. including the first females for the species, while a series of males and females from Spain are described and figured as Iberomaimetsha Ortega-Blanco, Perrichot & Engel, gen. n., with the two new species Iberomaimetsha rasnitsyni Ortega-Blanco, Perrichot & Engel, sp. n. and I. nihtmara Ortega-Blanco, Delclòs & Engel, sp. n.; a single female from Lebanon is described and figured as Ahiromaimetsha najlae Perrichot, Azar, Nel & Engel, gen. et sp. n., and a single male from Canada is described and figured as Ahstemiam cellula McKellar & Engel, gen. et sp. n. The taxa are compared with other maimetshids, a key to genera and species is given, and brief comments made on the family.

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A manga é uma espécie originária da Índia, estando atualmente distribuída por praticamente todas as regiões tropicais do mundo, sendo cultivada comercialmente também em algumas regiões de clima subtropical. O interesse pela cultura deve-se à excelência de seus frutos que, além de apresentar sabor exótico, são ricos em vitaminas e sais minerais, sendo uma das frutas mais ricas em vitamina A. O objetivo do presente trabalho foi estudar o efeito de diferentes temperaturas de aplicação de etileno exógeno sobre a qualidade de manga 'Tommy Atkins'. Os tratamentos foram: T1= frutos armazenados sob condições não controladas (24ºC ±5ºC e 65% UR) e não aplicação de etileno (tratamento-controle); T2= frutos sob condições não controladas, com 25 ppm de etileno, por 2 dias (24ºC ±5ºC e 65% UR); T3= frutos sob temperatura de 16°C ±1ºC e 90% UR, com 25 ppm de etileno, por 2 dias; T4= frutos sob temperatura de 18°C ±1ºC e 90% UR, com 25 ppm de etileno, por 2 dias; T5= frutos sob temperatura de 20°C ±1ºC e 90% UR, com 25 ppm de etileno, por 2 dias; T6= frutos sob temperatura de 22°C ±1ºC e 90% UR, com 25 ppm de etileno, por 2 dias, e T7= frutos sob temperatura de 24°C ±1ºC e 90% UR, com 25 ppm de etileno, por 2 dias. Após os tratamentos, os frutos foram armazenados a 20ºC ±1ºC e 90% UR (T3 a T7) e a condições ambientais não controladas (24ºC ±5ºC e 65% UR), nos tratamentos T1 e T2, por 14 dias. Avaliaram-se os frutos na colheita (caracterização), após os tratamentos no dia 0, no 7° e no 14° dias. Determinaram-se: sólidos solúveis totais, acidez titulável, índice de coloração do pericarpo e da polpa, firmeza manual do fruto e podridões. Conclui-se que a temperatura de 20ºC é a sugerida para a aplicação de etileno exógeno para o amadurecimento uniforme de manga 'Tommy Atkins'.

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Objective: To evaluate the agreement between multislice CT (MSCT) and intravascular ultrasound (IVUS) to assess the in-stent lumen diameters and lumen areas of left main coronary artery (LMCA) stents. Design: Prospective, observational single centre study. Setting: A single tertiary referral centre. Patients: Consecutive patients with LMCA stenting excluding patients with atrial fibrillation and chronic renal failure. Interventions: MSCT and IVUS imaging at 9-12 months follow-up were performed for all patients. Main outcome measures: Agreement between MSCT and IVUS minimum luminal area (MLA) and minimum luminal diameter (MLD). A receiver operating characteristic (ROC) curve was plotted to find the MSCT cut-off point to diagnose binary restenosis equivalent to 6 mm2 by IVUS. Results: 52 patients were analysed. Passing-Bablok regression analysis obtained a β coefficient of 0.786 (0.586 to 1.071) for MLA and 1.250 (0.936 to 1.667) for MLD, ruling out proportional bias. The α coefficient was −3.588 (−8.686 to −0.178) for MLA and −1.713 (−3.583 to −0.257) for MLD, indicating an underestimation trend of MSCT. The ROC curve identified an MLA ≤4.7 mm2 as the best threshold to assess in-stent restenosis by MSCT. Conclusions: Agreement between MSCT and IVUS to assess in-stent MLA and MLD for LMCA stenting is good. An MLA of 4.7 mm2 by MSCT is the best threshold to assess binary restenosis. MSCT imaging can be considered in selected patients to assess LMCA in-stent restenosis

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En esta investigación se analiza la competitividad de las exportaciones de manzanas de la región del Maule, Chile, en los mercados asiáticos de China, Hong Kong, Taiwán e India. El objetivo fue identificar estrategias competitivas y determinar las variables de ventaja competitiva de mayor relevancia. Para determinar los constructos estratégicos se realizó un bootstrap junto con un análisis factorial de componentes principales (PCA). Los constructos encontrados indican que las estrategias competitivas del sector exportador está orientado en lograr economías de escalas y optimizar procesos productivos y comerciales, para lograr menores costos y competir eficientemente en los mercados asiáticos.

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Wheat plants (Triticum durum Desf., cv. Regallo) were grown in the field to study the effects of contrasting [CO2] conditions (700 versus 370 μmol mol−1) on growth, photosynthetic performance, and C management during the post-anthesis period. The aim was to test whether a restricted capacity of sink organs to utilize photosynthates drives a loss of photosynthetic capacity in elevated CO2. The ambient 13C/12C isotopic composition (δ13C) of air CO2 was changed from-10.2 in ambient [CO2] to-23.6 under elevated [CO2] between the 7th and the 14th days after anthesis in order to study C assimilation and partitioning between leaves and ears. Elevated [CO2] had no significant effect on biomass production and grain filling, and caused an accumulation of C compounds in leaves. This was accompanied by up-regulation of phosphoglycerate mutase and ATP synthase protein content, together with down-regulation of adenosine diphosphate glucose pyrophosphatase protein. Growth in elevated [CO2] negatively affected Rubisco and Rubisco activase protein content and induced photosynthetic down-regulation. CO2 enrichment caused a specific decrease in Rubisco content, together with decreases in the amino acid and total N content of leaves. The C labelling revealed that in flag leaves, part of the C fixed during grain filling was stored as starch and structural C compounds whereas the rest of the labelled C (mainly in the form of soluble sugars) was completely respired 48 h after the end of labelling. Although labelled C was not detected in the δ13C of ear total organic matter and respired CO2, soluble sugar δ13C revealed that a small amount of labelled C reached the ear. The 12CO2 labelling suggests that during the beginning of post-anthesis the ear did not contribute towards overcoming flag leaf carbohydrate accumulation, and this had a consequent effect on protein expression and photosynthetic acclimation.

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Legumes such as alfalfa (Medicago sativa L.) are vital N2-fixing crops accounting for a global N2 fixation of ~35 MtNyear-1. Although enzymatic and molecular mechanisms of nodule N2 fixation are now well documented, some uncertainty remains as to whether N2 fixation is strictly coupled with photosynthetic carbon fixation. That is, the metabolic origin and redistribution of carbon skeletons used to incorporate nitrogen are still relatively undefined. Here, we conducted isotopic labelling with both 15N2 and 13C-depleted CO2 on alfalfa plants grown under controlled conditions and took advantage of isotope ratio mass spectrometry to investigate the relationship between carbon and nitrogen turn-over in respired CO2, total organic matter and amino acids. Our results indicate that CO2 evolved by respiration had an isotopic composition similar to that in organic matter regardless of the organ considered, suggesting that the turn-over of respiratory pools strictly followed photosynthetic input. However, carbon turn-over was nearly three times greater than N turn-over in total organic matter, suggesting that new organic material synthesised was less N-rich than pre-existing organic material (due to progressive nitrogen elemental dilution) or that N remobilisation occurred to sustain growth. This pattern was not consistent with the total commitment into free amino acids where the input of new C and N appeared to be stoichiometric. The labelling pattern in Asn was complex, with contrasted C and N commitments in different organs, suggesting that neosynthesis and redistribution of new Asn molecules required metabolic remobilisation. We conclude that the production of new organic material during alfalfa growth depends on both C and N remobilisation in different organs. At the plant level, this remobilisation is complicated by allocation and metabolism in the different organs. Additional keywords: carbon exchange, carbon isotopes, nitrogen fixation, nitrogen 15 isotope

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Extreme weight conditions (EWC) groups along a continuum may share some biological risk factors and intermediate neurocognitive phenotypes. A core cognitive trait in EWC appears to be executive dysfunction, with a focus on decision making, response inhibition and cognitive flexibility. Differences between individuals in these areas are likely to contribute to the differences in vulnerability to EWC. The aim of the study was to investigate whether there is a common pattern of executive dysfunction in EWC while comparing anorexia nervosa patients (AN), obese subjects (OB) and healthy eating/weight controls (HC).

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Selection of amino acid substitutions associated with resistance to nucleos(t)ide-analog (NA) therapy in the hepatitis B virus (HBV) reverse transcriptase (RT) and their combination in a single viral genome complicates treatment of chronic HBV infection and may affect the overlapping surface coding region. In this study, the variability of an overlapping polymerase-surface region, critical for NA resistance, is investigated before treatment and under antiviral therapy, with assessment of NA-resistant amino acid changes simultaneously occurring in the same genome (linkage analysis) and their influence on the surface coding region.

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By modifying a domain first suggested by Ruth Goodman in 1935 and by exploiting the explicit solution by Fedorov of the Polyá-Chebotarev problem in the case of four symmetrically placed points, an improved upper bound for the univalent Bloch-Landau constant is obtained. The domain that leads to this improved bound takes the form of a disk from which some arcs are removed in such a way that the resulting simply connected domain is harmonically symmetric in each arc with respect to the origin. The existence of domains of this type is established, using techniques from conformal welding, and some general properties of harmonically symmetric arcs in this setting are established.

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We prove upper pointwise estimates for the Bergman kernel of the weighted Fock space of entire functions in $L^{2}(e^{-2\phi}) $ where $\phi$ is a subharmonic function with $\Delta\phi$ a doubling measure. We derive estimates for the canonical solution operator to the inhomogeneous Cauchy-Riemann equation and we characterize the compactness of this operator in terms of $\Delta\phi$.