931 research outputs found

    Determination of Evapotranspiration and Crop Coefficient of Cactus Pear (Opuntia ficus-indica Mill.) with an Energy Balance Technique

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    A micrometeorological approach based on surface renewal technique was adopted to estimate evapotranspiration fluxes and crop coefficient data from an irrigated cactus pear (Opuntia ficus-indica Mill.) orchard under Mediterranean climatic conditions. High-frequency temperature readings were taken above the canopy top in order to get surface renewal sensible heat flux values (HSR). These values were compared against eddy covariance sensible heat fluxes (HEC) for calibration. Latent heat flux (or evapotranspiration, ET) was obtained as the residual of the energy balance equation using HSR. In field measurements of biophysical crop features, physiological characteristic and soil hydraulic components were integrated with the analysis of the surface energy fluxes. Microlysimeters were used to compute evaporation rates, allowing the separation of transpiration from ET data. During the irrigation season, evapotranspiration from the cactus pear orchard was 330 mm of water producing 16,210 kg of dry matter ha-1 for a biomass water productivity: WPb = kg biomass m-2 per kg H2O m-2 = 6.6 710-3. The water use efficiency (WUE) was 204 kg H2O kg-1 dry matter. The low value of WPb, relative to other CAM plants, suggests an opportunity to improve the use of irrigation water

    Determination of Evapotranspiration and Annual Biomass Productivity of a Cactus Pear [Opuntia ficus-indica L. (Mill.)] Orchard in a Semiarid Environment

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    A micrometeorological approach based on the surface energy balance was adopted to estimate evapotranspiration fluxes and crop coefficient data from an irrigated cactus pear [Opuntia ficus-indica L. (Mill.)] orchard under Mediterranean climatic conditions. Highfrequency temperature readings were taken above the canopy top to get sensible heat flux values (HSR) using the surface renewal technique. These values were compared against eddy covariance sensible heat fluxes (HEC) for calibration. Latent heat flux (or evapotranspiration, ET) was obtained by solving the daily energy balance equation. Measurements of soil hydraulic components were integrated with the analysis of the surface energy fluxes and crop development in terms of phenology and aboveground biomass accumulation. Microlysimeters were used to compute evaporation rates, allowing the separation of daily transpiration from ET data. Ecophysiological measurements were carried to estimate dry weight accumulation and partitioning. Cactus pear evapotranspired a total of approximately 286 and 252 mm of water during the two monitored growing seasons, respectively. Average daily values of crop (ETc) and reference (ET0) evapotranspiration were in the order of 2.5 and 5.0 mm, respectively, with a corresponding value of the mean crop coefficient of approximately 0.40. The annual dry mass fixed per single tree was 38.8 1.3 kg, with a total production of 12.9 t ha 121, which is comparable to many C3 and C4 plants and resulted in a water use efficiency (WUE) of 4.6 and 4.4 gDMkgH2O 121 in 2009 and 2010, respectively. The stem area index (SAI) was 3.5

    Characterization and development of different methods to extend shelf life of fresh cut fruit. Case study: novel controlled release system by layer-by-layer assembly

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    The research project aimed at the investigation of different methods for the storage of fresh-cut fruit. This case study relates to the proposal of an innovative controlled release system to improve the shelf life of ready-to-eat fruit. The methods applied during three research years included the application of active molecules from natural substances, some widely used in commerce and other tested for the first time; first analyzed in vitro and then applied in vivo. The under consideration methods concerned dipping, coating and the layer-by-layer assembly. The analysis carried out on the fruit have monitored pomological traits performances (soluble solids content, titratable acidity, pH, color, flesh firmness), the chemical profile (polyphenoloxidase, carotenoids) and microbial growth

    Human-Scale Virtual Environment for Product Design: Effect of Sensory Substitution

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    This paper presents a human-scale virtual environment (VE) with haptic feedback along with two experiments performed in the context of product design. The user interacts with a virtual mock-up using a large-scale bimanual string-based haptic interface called SPIDAR (Space Interface Device for Artificial Reality). An original self-calibration methodis proposed. A vibro-tactile glove was developed and integrated to the SPIDAR to provide tactile cues to the operator. The purpose of the first experiment was: (1) to examine the effect of tactile feedback in a task involving reach-and-touch of different parts of a digital mock-up, and (2) to investigate the use of sensory substitution in such tasks. The second experiment aimed to investigate the effect of visual and auditory feedback in a car-light maintenance task. Results of the first experiment indicate that the users could easily and quickly access and finely touch the different parts of the digital mock-up when sensory feedback (either visual, auditory, or tactile) was present. Results of the of the second experiment show that visual and auditory feedbacks improve average placement accuracy by about 54 % and 60% respectively compared to the open loop case.

    A Flexible Software Framework for Magnetic Measurements at CERN: a Prototype for the new Generation of Rotating Coils

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    A new software platform named FFMM (Flexible Framework for Magnetic Measurements) is under development at CERN (European Organization for Nuclear Research) in cooperation with the University of Sannio. The FFMM is aimed at facing the new test requirements arising after the production series of the Large Hadron Collider magnets. In particular, the basic concepts of the FFMM, its architecture, and the experimental implementation of a demonstrator are illustrated in order to show how the quality requirements of software flexibility and scalability are met

    Quality changes during postharvest life in white fleshed peach (Prunus Persica L. Batsch) fruits: Preliminary observations

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    Sicilian white flesh peach fruits ecotypes are characterized by a persistent aroma and excellent flavor that is highly appreciated by consumers. Nevertheless, they reach only regional markets, because of fruit sensitivity to decay and the poor information about their postharvest physiology and shelf-life. In this trial, we studied quality changes during postharvest life of non-melting white-flesh peach ecotypes \u2018Tudia\u2019, \u2018Bella di Bivona\u2019 and the cultivar \u2018Daniela\u2019. Fruits were collected at commercial ripening: a first group was submitted to analytical evaluations and another one was stored (2\ub0C, 90% RH) for 32 days. During this storage period, fruits were submitted to four shelf-life periods at ambient temperature (22\ub0C) for 6 days and analyzed every 3th and 6th day. In the period of shelf-life, during storage of fruit at 2\ub0C, we ascertained that Bella di Bivona and Daniela have a shelf-life of 12-14 days while \u2018Tudia\u2019 could reach up to 25-32 days. Flesh firmness and chilling injuries trends, during shelf-life, allowed to discover \u2018Tudia\u2019 as the variety which presents the best performance after storage at low temperatures for long periods

    Effect of harvest date on mango (Mangifera indica l. cultivar osteen) fruit’s qualitative development, shelf life and consumer acceptance

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    The qualitative characteristics of mango fruits change throughout their development process and are also influenced by their duration. Harvesting at different times after the fruit set affects external and internal quality and the post-harvest behavior and management possibilities of the fruits. The objective of this study was to assess the evolution of the most important physicochemical and organoleptic parameters of cv. Osteen fruits concern the length of their stay on the plant and also to their post-harvest management. For this reason, fruits were harvested progressively in ten pickings. The study showed that mango fruits that are kept on the tree reach the best quality traits, corresponding to their physiological maturation. The length of the storage period needed to reach the consumption point varies greatly according to the harvesting moment and to the different environmental parameters, which also affect the organoleptic and physicochemical quality of the fruits. The number of days after full flowering were confirmed to be the primary information to consider when planning harvest with commercial use of the fruit, but interesting indications can be acquired through the definition of non-destructive (hardness, color) or destructive (dry matter) parameters. The data collected help improve mango fruit′ s post-harvest management practices, to provide a product with constant quality and homogeneity to the consumer

    SPUTNIK: an R package for filtering of spatially related peaks in mass spectrometry imaging data

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    Summary: SPUTNIK is an R package consisting of a series of tools to filter mass spectrometry imaging peaks characterized by a noisy or unlikely spatial distribution. SPUTNIK can produce mass spectrometry imaging datasets characterized by a smaller but more informative set of peaks, reduce the complexity of subsequent multi-variate analysis and increase the interpretability of the statistical results. Availability: SPUTNIK is freely available online from CRAN repository and at https://github.com/paoloinglese/SPUTNIK. The package is distributed under the GNU General Public License version 3 and is accompanied by example files and data. Supplementary information: Supplementary data are available at Bioinformatics online

    Use of xanthan gum and calcium ascorbate to prolong cv. Butirra pear slices shelf life during storage

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    After cut, pear fruit (Pyrus communis L.) during shelf life can be subjected to color and flavor changes. To maintain flesh colour and firmness, different technologies could be employed during shelf life, such as chemical, physical and edible coating treatments. In the present study, the effects of two edible coating formulations containing xanthan gum and calcium ascorbate on fresh­cut pear fruit were investigated. After harvest, 200 fruits were cut and coated with Xanthan Gum (XAN) and distilled water or Xanthan gum + Calcium Ascorbate (ASC), respectively, while control (CTR) pear fruit slices were soaked in distilled water and lastly packed in polyethylene terephthalate (PET) packages sealed with a composite film (PP­PET). All samples were stored at 5±0.5°C with RH 90% for 10 days. Measurements were carried out at 3, 5, 7 and 10 days of storage evaluating visual quality score, browning index, color, total solid soluble content (TSS), flavor, ascorbic acid content and total phenols content. The results showed that ASC treatment was the most efficient treatment in terms of color changes, ascorbic acid content, visual quality score and browning index, until the 7th day of storage. Moreover, (ASC) treatment reported lower mean values in terms of taste and flavor score if compared to CTR and XAN treatments. Untreated pear slices (CTR) kept good values concerning flavor score until the 3rd day of storage while on the 5th and 7th day off­flavor values were the same as treated samples

    Food quality, sensory attributes and nutraceutical value of fresh “Osteen” mango fruit grown under mediterranean subtropical climate compared to imported fruit

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    Mango is a fruit with a very short shelf-life due to its rapid ripeness after harvest; it is high in B vitamins, contains some amounts of magnesium, calcium, zinc, and selenium and it is rich in soluble and insoluble fibers. In order to reach the European markets at proper marketable maturity, fruit from tropical countries are harvested at early maturity stage. Although this harvesting practice improves mango postharvest life, fruit reach the market with very low quality, especially in terms of taste. The present study was conducted to evaluate food quality, sensory attributes and nutraceutical value of “Osteen” fresh Mediterranean Italian mango fruit, and imported ones coming from tropical countries. Mango fruit imported from abroad were collected from 5 large-scale organized markets; fresh Italian mango fruit were harvested from a commercial orchard, at green-and mature-ripe stage. Imported and fresh Italian mango fruit were analyzed in terms of firmness, total soluble solids content, titratable acidity, flesh disorders, nutraceutical value, and sensory attributes. Mediterranean Italian mango fruit showed the best quality performances in terms of nutraceutical value and quality attributes. Sensorial analysis confirmed this behavior, these quality attributes, were perceived by the trained panel, that preferred fresh Mediterranean mango fruit
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