112 research outputs found

    Composing Processes Using Modified Rely-Guarantee Specifications

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    We present a specification notation for components of concurrent systems and an accompanying proof methodology for reasong about the composition of these components. The specification construct is motivated by rely-guarantee pairs and by any-component program properties. The proof technique is based on an implication ladder and on two basic properties from which more complex properties are derived. Two examples illustrate the simplicity and compositionality of the model, and demonstrate how the model can be used to create structured and reusable proofs of distributed systems

    Reliable Synchronization Primitives for Java

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    Java is an architecture-independent, object-oriented language designed to facilitate code-sharing across the Internet in general, via the Web in particular. Java is multithreaded, providing thread creation and synchronization constructs based on generalized monitors. Although these primitives are appropriate for many windowing applications, they are not necessarily well-suited for the larger class of multithreaded programs that occur as part of distributed systems. We demonstrate how the Java primitives, in conjunction with the object-oriented aspects of the language, can be used to implement a collection of other traditional synchronization paradigms. These paradigms are formally specified, their implementations are rigorously verified, and their use is illustrated with several examples

    Using parse tree validation to prevent SQL injection attacks

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    An SQL injection attack targets interactive web applications that employ database services. Such applications accept user input, such as form fields, and then include this input in database requests, typically SQL statements. In SQL injection, the attacker provides user input that results in a different database request than was intended by the application programmer. That is, the interpretation of the user input as part of a larger SQL statement, results in an SQL statement of a different form than originally intended. We describe a technique to prevent this kind of manipulation and hence eliminate SQL injection vulnerabilities. The technique is based on comparing, at run time, the parse tree of the SQL statement before inclusion of user input with that resulting after inclusion of input. Our solution is efficient, adding about 3 ms overhead to database query costs. In addition, it is easily adopted by application programmers, having the same syntactic structure as current popular record set retrieval methods. For empirical analysis, we provide a case study of our solution in J2EE. We implement our solution in a simple static Java class, and show its effectiveness and scalability. 1

    Changes in Within-Shoot Carbon Partitioning in Pinot Noir Grapevines Subjected to Early Basal Leaf Removal

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    Early leaf removal significantly alters the source-sink balance within grapevine shoots, leading to a reduction in fruit set. However, no research has previously examined the conditions controlling this process in terms of carbon allocation among major sink organs following defoliation. In this study, the impact of defoliation at bloom on the distribution dynamics of leaf assimilates among clusters and growing shoot apices was investigated on Vitis vinifera, cv. Pinot noir, grown in Michigan, a cool climate viticultural region. Three levels of defoliation: no leaves removed (LR-0); six leaves removed from six basal nodes (LR-6); and ten leaves removed from ten basal nodes (LR-10), were imposed at full bloom. A 13C pulsing was performed 1 week after the treatment application to the defoliated shoots. Single leaf gas exchange (Pn), diurnal changes of the leaf net CO2 assimilation rate, carbon distribution, fruit-set, yield, and fruit composition were measured. Higher Pn was recorded in diurnal measurements of gas exchange in leaf removal (LR) treatments compared to LR-0. The shoot apex of LR-10 experienced the highest 13C allocation (%) after 3 and 7 days following the carbon pulsing. LR-10 had lower percentage of 13C allocated to clusters, which decreased fruit set by 60%, compared to the control, and enhanced the concentration of phenolic compounds in fruit. Alteration of carbon portioning among shoot sink organs indicated that an increasing severity of leaf removal significantly reduced fruit set, and was linearly correlated to shoot apex sink strength, which occurred at the expense of the cluster

    The calibration of the sprayers and the factors involved in coverage uniformity in the vineyard

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    The phytopathological condition of the vineyard and the reduction in the use of crop protection products are closely linked to the efficiency of the use of sprayers. The objective of the work was to identify the best operative conditions to improve the canopy coverage of the spraying. From 2012 to 2017 173 field trials were carried out in 40 farms, on 24 varieties, testing 72 different sprayers in North Eastern Italy. Water-sensitive papers of 2.5 × 2.5 cm were positioned in eight points in the vine canopy according to a standardized method, and they were examined after spraying for spray deposition. In general, results showed that coverage of the lower leaf surface was very poor. On the contrary, the upper section of leaves in the outer canopy layers have received excessive spraying, over 70% coverage in 25% of cases. The coverage uniformity was improved by using driving speeds lower than 6 km / h and using upward air flow direction

    The calibration of the sprayers and the factors involved in coverage uniformity in the vineyard

    Get PDF
    The phytopathological condition of the vineyard and the reduction in the use of crop protection products are closely linked to the efficiency of the use of sprayers. The objective of the work was to identify the best operative conditions to improve the canopy coverage of the spraying. From 2012 to 2017 173 field trials were carried out in 40 farms, on 24 varieties, testing 72 different sprayers in North Eastern Italy. Water-sensitive papers of 2.5 × 2.5 cm were positioned in eight points in the vine canopy according to a standardized method, and they were examined after spraying for spray deposition. In general, results showed that coverage of the lower leaf surface was very poor. On the contrary, the upper section of leaves in the outer canopy layers have received excessive spraying, over 70% coverage in 25% of cases. The coverage uniformity was improved by using driving speeds lower than 6 km / h and using upward air flow direction

    UHPLC-MS/MS determination of varietal thiol precursors in Sauvignon Blanc grapes

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    6siVarietal thiol precursors in grapes are subject to metabolic changes during post-harvest treatments. Metabolic activity should therefore be limited after sampling to understand their biosynthesis in the berry and genetic regulation. In this study, berries were frozen in liquid nitrogen immediately after harvesting, transported in dry ice, stored briefly at -80 °C, cryo-milled and extracted without being thawed in cold methanol in a ratio of 1:4 (w/v). A UHPLC-MS/MS method for quantitative determination of the thiol precursors 3-S-glutathionylhexan-1-ol (G3MH), 3-S-cysteinylhexan-1-ol (Cys3MH), 4-S-glutathionyl-4-methylpentan-2-one (G4MMP) and 4-S-cysteinyl-4-methylpentan-2-one (Cys4MMP), glutathione, oxidized glutathione and L-methionine in grapes was developed. Reference material was provided through synthesis of precursors and their deuterium labelled analogues. The average thiol precursor content in grapes in 2013-15 was in the range 8-16 μg kg(-1) for G3MH, 1-6 μg kg(-1) for Cys3MH, 1-4 μg kg(-1) for Cys4MMP and 0.3 μg kg(-1) for G4MMP. In 2013 and 2014, the highest precursor content in mature Sauvignon Blanc grapes from vineyards located in Italy regarded G3MH, followed by Cys3MH, Cys4MMP and G4MMP. In 2015, G3MH was again the most abundant precursor, but followed by Cys4MMP, Cys3MH and G4MMP.openopenVanzo, Andreja; Janeš, Lucija; Požgan, Franc; Velikonja Bolta, Špela; Sivilotti, Paolo; Lisjak, KlemenVanzo, Andreja; Janeš, Lucija; Požgan, Franc; Velikonja Bolta, Špela; Sivilotti, Paolo; Lisjak, Kleme

    Grape lipidomics: an extensive profiling thorough UHPLC–MS/MS method

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    8openInternationalItalian coauthor/editorLipids play many essential roles in living organisms, which accounts for the great diversity of these amphiphilic molecules within the individual lipid classes, while their composition depends on intrinsic and extrinsic factors. Recent developments in mass spectrometric methods have significantly contributed to the widespread application of the liquid chromatography-mass spectrometry (LC–MS) approach to the analysis of plant lipids. However, only a few investigators have studied the extensive composition of grape lipids. The present work describes the development of an ultrahigh performance liquid chromatography tandem mass spectrometry (UHPLC–MS/MS) method that includes 8098 MRM; the method has been validated using a reference sample of grapes at maturity with a successful analysis and semi-quantification of 412 compounds. The aforementioned method was subsequently applied also to the analysis of the lipid profile variation during the Ribolla Gialla cv. grape maturation process. The partial least squares (PLS) regression model fitted to our experimental data showed that a higher proportion of certain glycerophospholipids (i.e., glycerophosphoethanolamines, PE and glycerophosphoglycerols, PG) and of some hydrolysates from those groups (i.e., lyso-glycerophosphocholines, LPC and lyso-glycerophosphoethanolamines, LPE) can be positively associated with the increasing °Brix rate, while a negative association was found for ceramides (CER) and galactolipids digalactosyldiacylglycerols (DGDG). The validated method has proven to be robust and informative for profiling grape lipids, with the possibility of application to other studies and matrices.openMasuero, Domenico; Škrab, Domen; Chitarrini, Giulia; Garcia-Aloy, Mar; Franceschi, Pietro; Sivilotti, Paolo; Guella, Graziano; Vrhovsek, UrskaMasuero, D.; Škrab, D.; Chitarrini, G.; Garcia-Aloy, M.; Franceschi, P.; Sivilotti, P.; Guella, G.; Vrhovsek, U

    Carbon partitioning between shoot organs following early leaf removal

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    In grapevines, basal leaf removal at bloom often induces a reduction of fruit set. The effect is related to a reduction in carbon availability for different plant organs competing for photosynthates. To understand and quantify carbon allocation among major sink organs following the early basal leaf removal, the effect of early basal defoliation was studied in Pinot noir grapevines. The experiment was performed in Michigan, a cool climate viticultural region, and three levels of defoliation were imposed at full bloom: (1) no leaves removed (DF-0); (2) six leaves removed from six basal nodes (DF-6); and (3) ten leaves removed from ten basal nodes (DF-10). A week after the defoliation treatment, 13C pulsing was executed to the defoliated shoots. Photosynthesis (Pn), carbon distribution, fruit set, vine performance and basic fruit composition were measured. LR treatments induced higher Pn when compared to LR-0. The highest 13C allocation (%) was recorded in the shoot apex of the LR-10 treatment and LR-10 had the lowest percentage of 13C transported to the cluster, with a reduced fruit set of about 60% when compared to LR-0. The severity of leaf removal reduced significantly fruit set and increased shoot apex sink strength at the expense of the cluster

    Carbon partitioning between shoot organs following early leaf removal

    Get PDF
    In grapevines, basal leaf removal at bloom often induces a reduction of fruit set. The effect is related to a reduction in carbon availability for different plant organs competing for photosynthates. To understand and quantify carbon allocation among major sink organs following the early basal leaf removal, the effect of early basal defoliation was studied in Pinot noir grapevines. The experiment was performed in Michigan, a cool climate viticultural region, and three levels of defoliation were imposed at full bloom: (1) no leaves removed (DF-0); (2) six leaves removed from six basal nodes (DF-6); and (3) ten leaves removed from ten basal nodes (DF-10). A week after the defoliation treatment, 13C pulsing was executed to the defoliated shoots. Photosynthesis (Pn), carbon distribution, fruit set, vine performance and basic fruit composition were measured. LR treatments induced higher Pn when compared to LR-0. The highest 13C allocation (%) was recorded in the shoot apex of the LR-10 treatment and LR-10 had the lowest percentage of 13C transported to the cluster, with a reduced fruit set of about 60% when compared to LR-0. The severity of leaf removal reduced significantly fruit set and increased shoot apex sink strength at the expense of the cluster
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