219 research outputs found

    Role of cell wall on tomato fruit susceptibility to calcium deficiency disorder

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    The objectives of this study were to evaluate the effect of Ca2+ binding to the cell wall 14 on fruit susceptibility to BER

    Escaldadura superficial em maçãs Granny Smith submetidas ao tratamento térmico com cálcio.

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    O objetivo deste trabalho foi avaliar o efeito do tratamento térmico combinado com Ca2+ sobre o desenvolvimento de escaldadura superficial em maçãs Granny Smith após o armazenamento refrigerado

    Mechanisms regulating bitter pit development in Greensleeves apples with suppression of ethylene biosynthesis.

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    The objectives of this study were to understand the role of ethylene and nutrients (Ca2+,Mg2+, K+ and N) on bitter pit (BP) development in wild type (GS) and ethylene suppressed (68G and 103Y) Greensleeves apples. The transgenic line 68G is suppressed for 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase (ACO) and line 103Y is suppressed for ACC synthase (ACS). Suppression of ethylene biosynthesis reduced BP incidence and severity. Lower ethylene biosynthesis, in ethylene-suppressed genotypes, had no effect on Ca2+, Mg2+, K+ and N concentrations in fruit cortical tissue. In all genotypes, fruit with BP had lower Ca2+ and higher Mg2+ concentrations and higher Mg2+/Ca2+ ratio in cortical tissue. The results indicate that high levels of ethylene biosynthesis and Mg2+ in cortical tissue can enhance fruit susceptibility to BP incidence

    Calcium partitioning and allocation and blossom-end rot development in tomato plants in response to whole-plant and fruit-specific abscisic acid treatments.

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    The objectives of this study were to determine Ca2+ partitioning and allocation in tomato plants and fruit in response to whole-plant and fruit-specific ABA treatments, as well as to analyse the effect of changes in Ca2+ partitioning and allocation on fruit susceptibility to BER under water stress conditions

    Post-bloom and preharvest treatment of Braeburn apple trees with prohexadione-calcium and GA4+7 affects vegetative growth and postharvest incidence of calcium-related physiological disorders and decay in the fruit.

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    Calcium (Ca) deficiency disorders in apple fruit have been associated with high gibberellins (GAs) activity in the tree. This study was carried out to assess the effects of treatments of ?Braeburn? apple trees with prohexadione-calcium (ProCa, an inhibitor of GAs biosynthesis) or gibberellins (GA4+7) on vegetative growth of the trees and postharvest incidence of Ca-related physiological disorders and decay in the fruit. ProCa (300?mg?L-1) or GA4+7 (300?mg?L-1) treatments were applied post-bloom (PB) and preharvest (PH). PB treatments started 15 days after full bloom (DAFB), with one application every week and six applications in total. PH treatments started five weeks before anticipated harvest (125 DAFB), with one application every week and four applications in total. Control trees were left untreated. When applied PB, ProCa reduced and GA4+7 promoted vegetative growth of the trees. ProCa PB delayed the impairment of xylem functionality (at the proximal region of the fruit) during fruit growth on the tree. Treatments had no effect on fruit weight, pectinmethylesterase (PME) activity or the expression of CAX3, CAX6 and V-ATPase (transporters of Ca into the vacuole) genes assessed in the external cortical tissue at the distal end of the fruit at harvest. When sprayed PB, ProCa increased the total Ca content and reduced K/Ca, Mg/Ca, N/Ca, (Mg?+?K)/Ca and (K?+?Mg?+?N)/Ca ratios in the flesh at the distal portion of the fruit, compared to the treatment with GA4+7, but without differing from the control. In general, ProCa application PB or PH reduced the expression of Ca-ATPase1, Ca-ATPase2, H+-PPase and CAX2 (Ca transporters into the vacuole) genes, increased total water?soluble Ca and reduced electrolyte leakage in the fruit at harvest. After two months of cold storage followed by five days of shelf-life, the incidence and severity of bitter pit (BP) was lower on fruit from trees treated with ProCa PH, and higher on fruit from trees treated with GA4+7 PB. GA4+7 PB also increased the incidence of skin cracking and decay in the fruit. The results showed that ProCa application represents a feasible tool to reduce the incidence of BP. However, ProCa is more effective to reduce BP if applied weekly for five week before harvest

    A transcriptome approach towards understanding the development of ripening capacity in Bartlett pears (Pyrus communis L.).

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    The capacity of European pear fruit (Pyrus communis L.) to ripen after harvest develops during the final stages of growth on the tree. The objective of this study was to characterize changes in Bartlett pear fruit physico-chemical properties and transcription profiles during fruit maturation leading to attainment of ripening capacity

    Designing a Good Life: A Matrix for the Technological Mediation of Morality

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    Technologies fulfill a social role in the sense that they influence the moral actions of people, often in unintended and unforeseen ways. Scientists and engineers are already accepting much responsibility for the technological, economical and environmental aspects of their work. This article asks them to take an extra step, and now also consider the social role of their products. The aim is to enable engineers to take a prospective responsibility for the future social roles of their technologies by providing them with a matrix that helps to explore in advance how emerging technologies might plausibly affect the reasons behind people’s (moral) actions. On the horizontal axis of the matrix, we distinguished the three basic types of reasons that play a role in practical judgment: what is the case, what can be done and what should be done. On the vertical axis we distinguished the morally relevant classes of issues: stakeholders, consequences and the good life. To illustrate how this matrix may work in practice, the final section applies the matrix to the case of the Google PowerMeter

    Why simulation can be efficient: on the preconditions of efficient learning in complex technology based practices

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    <p>Abstract</p> <p>Background</p> <p>It is important to demonstrate learning outcomes of simulation in technology based practices, such as in advanced health care. Although many studies show skills improvement and self-reported change to practice, there are few studies demonstrating patient outcome and societal efficiency.</p> <p>The objective of the study is to investigate if and why simulation can be effective and efficient in a hi-tech health care setting. This is important in order to decide whether and how to design simulation scenarios and outcome studies.</p> <p>Methods</p> <p>Core theoretical insights in Science and Technology Studies (STS) are applied to analyze the field of simulation in hi-tech health care education. In particular, a process-oriented framework where technology is characterized by its devices, methods and its organizational setting is applied.</p> <p>Results</p> <p>The analysis shows how advanced simulation can address core characteristics of technology beyond the knowledge of technology's functions. Simulation's ability to address skilful device handling as well as purposive aspects of technology provides a potential for effective and efficient learning. However, as technology is also constituted by organizational aspects, such as technology status, disease status, and resource constraints, the success of simulation depends on whether these aspects can be integrated in the simulation setting as well. This represents a challenge for future development of simulation and for demonstrating its effectiveness and efficiency.</p> <p>Conclusion</p> <p>Assessing the outcome of simulation in education in hi-tech health care settings is worthwhile if core characteristics of medical technology are addressed. This challenges the traditional technical versus non-technical divide in simulation, as organizational aspects appear to be part of technology's core characteristics.</p
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