340 research outputs found

    Occurrence and Etiology of Brown Apical Necrosis on Persian (English) Walnut Fruit.

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    In 1998, a severe fruit drop was observed in Italy, principally on cv. Lara Persian (English) walnut (Juglans regia). Dropped fruit showed a brown patch at the blossom end and blackening and rot of inner tissues. The disease, called brown apical necrosis (BAN), was investigated on fruit collected in Italy and France in 1999. In 2000, studies were carried out in three walnut orchards located in Italy and in France to substantiate the etiology of BAN. Isolations performed from inner diseased fruit tissues yielded several fungi, in decreasing frequency of isolation: species of Fusarium and Alternaria, and one species each of Cladosporium, Colletotrichum, and Phomopsis. However, only Fusarium spp. were recovered from stigmas of BAN-affected fruit. The fungi associated with BAN-diseased fruit and species composition differed among locations and over time, confirming results obtained in previous investigations. The species of Fusarium used in pathogenicity tests reproduced BAN-disease symptoms when inoculated on fruit, whereas an Alternaria alternata isolate caused only limited necrosis of the style. However, the role of the other fungi commonly isolated from BAN-diseased fruit remains to be defined. The walnut blight pathogen, Xanthomonas arboricola pv. juglandis, occasionally was isolated from BAN-diseased fruit. No correlation was found between the extent of external brown patches and the size of inner lesions. Repeated isolations from and inoculations of fruit demonstrated that BAN can be considered a complex disease, and the inner infections originate from the style of the fruit

    Hypoxia dictates metabolic rewiring of tumors: implications for chemoresistance

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    Hypoxia is a condition commonly observed in the core of solid tumors. The hypoxia-inducible factors (HIF) act as hypoxia sensors that orchestrate a coordinated response increasing the pro-survival and pro-invasive phenotype of cancer cells, and determine a broad metabolic rewiring. These events favor tumor progression and chemoresistance. The increase in glucose and amino acid uptake, glycolytic flux, and lactate production; the alterations in glutamine metabolism, tricarboxylic acid cycle, and oxidative phosphorylation; the high levels of mitochondrial reactive oxygen species; the modulation of both fatty acid synthesis and oxidation are hallmarks of the metabolic rewiring induced by hypoxia. This review discusses how metabolic-dependent factors (e.g., increased acidification of tumor microenvironment coupled with intracellular alkalinization, and reduced mitochondrial metabolism), and metabolic-independent factors (e.g., increased expression of drug efflux transporters, stemness maintenance, and epithelial-mesenchymal transition) cooperate in determining chemoresistance in hypoxia. Specific metabolic modifiers, however, can reverse the metabolic phenotype of hypoxic tumor areas that are more chemoresistant into the phenotype typical of chemosensitive cells. We propose these metabolic modifiers, able to reverse the hypoxia-induced metabolic rewiring, as potential chemosensitizer agents against hypoxic and refractory tumor cells

    ON THE LOCALIZED PHYSICAL EXERGY DISAGGREGATION FOR DISSIPATIVE COMPONENT ISOLATION IN THERMOECONOMICS

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    Thermoeconomics is a discipline that connects Thermodynamics and Economics concepts, usually used for rational cost allocation to the final products of a thermal plant, by means of a model that describes the cost formation process of the overall system. Generally, exergy or monetary costs of the external resources are distributed to the final products. Exergy is the thermodynamic magnitude used in thermoeconomics and the physical exergy disaggregation has been introduced in thermoeconomics as alternatives for the isolation of the dissipative components and residues allocation. For plants with dissipative equipment, such as condenser or valve, the productive diagram, based on total exergy (E Model), need to merge this dissipative equipment with other productive components. In order to isolate the condenser, the productive diagram must use, at least, the H&S Model and to isolate the valve, the UFS Model has to be considered.Both disaggregation models greatly increase the thermoeconomic modeling complexity. Bearing this in mind, this work aims to evaluate the advantages of combining the E Model with these other models in order to adequately isolate the dissipative equipment. The plants studied herein are two different steam turbine cogeneration systems, with dissipative components (condenser or valve). The different monetary and exergy unit costs obtained for the two final products of each plant are compared and analyzed.  The results show that localized physical exergy disaggregation for dissipative component isolation in thermoeconomics is feasible, since it reduces the complexity of the productive structure and is also consistent from the point of view of thermodynamics

    Mobile phone and tablet apps to support young people’s management of their physical long-term conditions: a systematic review protocol

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    Background: The prevalence of long-term or chronic conditions that limit activity and reduce quality of life in young people aged 10-24 years is rising. This group has distinct health care needs and requires tailored support strategies to facilitate increasing personal responsibility for the management of their condition wherever possible, as they mature. Mobile phone and tablet mobile technologies featuring software program apps are already well used by young people for social networking or gaming. They have also been utilized in health care to support personal condition management, using condition-specific and patient-tailored software. Such apps have much potential, and there is an emerging body of literature on their use in a health context making this review timely. Objective: The objective of this paper is to develop a systematic review protocol focused on identifying and assessing the effectiveness of mobile phone and tablet apps that support young people’s management of their chronic conditions. Methods: The search strategy will include a combination of standardized indexed search terms and free-text terms related to the key concepts of young people; long-term conditions and mobile technology. Peer-reviewed journal articles published from 2003 that meet the inclusion and exclusion criteria will be identified through searching the generated hits from 5 bibliographical databases. Two independent reviewers will screen the titles and abstracts to determine which articles focus on testing interventions identified as a mobile phone or tablet apps, and that have been designed and delivered to support the management of long-term conditions in young people aged 10-24 years. Data extraction and quality assessment tools will be used to facilitate consistent analysis and synthesis. It is anticipated that several studies will meet the selection criteria but that these are likely to be heterogeneous in terms of study design, reported outcomes, follow-up times, participants’ age, and health condition. Sub-group analyses will be undertaken and where possible meta-analyses will take place.Results: This review will synthesize available knowledge surrounding tablet and mobile phone apps that support management of long term physical health conditions in young people. The findings will be synthesized to determine which elements of the technologies were most effective for this population. Conclusions: This systematic review aims to synthesize existing literature in order to generate findings that will facilitate the development of an app intervention. The review will form the first phase of development and evaluation of a complex intervention as recommended by the United Kingdom Medical Research Council. The knowledge gained from the review will be verified in subsequent phases, which will include primary qualitative work with health professionals and young people with long term conditions as research participants. Young people living with long-term conditions will be involved as co-researchers and consumer advisors in all subsequent phases to develop and evaluate an app to support the management of long-term physical health conditions

    Informe de actividades primer semestre de 1996 :Creced Arauca

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    Para cualquiera que sea el sistema de producción agrícola la calidad de la semilla es el factor determinante del éxito o el fracaso. En los sistemas de economía campesina generalmente la semilla para siembra proviene de un cosecha anterior, obviamente el proceso de selección por parte del campesino, esta lleno de conocimientos ancestrales y de experiencias cotidianas que le permiten al productor conocer cierta calidad agronómica y botánica del cultivo, Sin embargo también desconoce algunos aspectos técnicos de selección y especialmente de conservación de semilla que se reflejan en la disminución de la calidad

    Crecimiento fetal y de otros componentes del útero grávito en cabras mestizas

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    Existe un ilimitado numera de estudios sobre crecimiento prenatal en caprinos. La información obtenida reviste Importancia en la estimación de requerimientos nutricionales en la fase de gestación Con el objetivo de aportar Información sobre la evolución de los pesos fetales y otros componentes del útero grávido, se realizó el presente estudio en la Universidad Federal de Viscosa, M G , Brasil.Caprinos-Capra hircu
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