The use of hyperspectral imaging in the visible and near infrared region to discriminate between table grapes harvested at different times

Traditional analytical methods applied to the measurement of grape maturity and quality index in order to assess optimal harvest time have been proved to be slow and destructive. Therefore, non-destructive analytical techniques, including spectroscopy, can be a valid support for the choice of the best time to harvest. This study evaluated the feasibility of using a visible and near infrared spectral scanner (v. 1.4; DV Srl, Padova, Italy) with a detector in the region between 400-1000 nm to discriminate between grapes harvested at different times. Twelve clusters were harvested at 5 different times between October and December 2011. Spectra were acquired with a Spectral scanner on 3 intact berries from each bunch. These were randomly selected from top, medium and bottom zones, for a total of 180 spectra. Classification models were construed comparing 2 methods: soft independent modelling of class analogy (SIMCA) and partial least squares discriminant analysis (PLS-DA). The SIMCA model was developed building individual principal component analysis (PCA) models for the spectra of each harvest time. Different pre-treatment methods were tested in order to enhance the power of the model, thus enhancing the score differences among samples from different harvest times. The transformation that allowed the best statistical separation among scores of grapes from different harvest times was the second derivate of Norris. Therefore, the PCA model obtained from the spectra subjected to this pre-treatment was used for SIMCA classification. The PLS-DA model were developed applying the PLS2 algorithm. In order to construct discriminant models to classify bunch spectra according to the 5 harvest times, spectral variations were correlated with the 5 categories established. No pretreatments were previously applied in this last case since they did not improve the final result. The SIMCA method was unable to correctly classify grapes from harvest time 2 (59% of correct classification) and was less efficient compared to the PLS-DA model. Using the PLS-DA model, all the grapes were correctly classified (100%) with the exception of those from harvest time 5 (94%). The overall results demonstrate that this method has excellent potential for discriminating grape quality

Spectra evolution over on-vine holding of Italia table grapes: prediction of maturity and discrimination for harvest times using a Vis-NIR hyperspectral device

Measurement of certain grape quality parameters (sugars, acidity, and pH-value) is essential for the determination of the optimum harvest time. Non-destructive analytical techniques, including near infrared (NIR) spectroscopy, can be valid alternatives to traditional analytical methods for the determination of maturity indexes, enabling the possibility of on-field applications. This work aims to study the reliability to monitor spectra changes related with ripening of table grapes and to select optimal wavelengths for the discrimination of bunches from different harvests, in addition to the prediction of total soluble solids, pH, titratable acidity, phenols and antioxidant activity of table grapes. Grapes were harvested four times from the same plants at day 0 (I HT), and after 11 (II HT), 27 (III HT) and 48 (IV HT) days. Spectra were acquired from the images obtained using a spectral scanner Vis-NIR (ver 1.4.; DV Srl, Padova, Italy), with a detector in the region between 400-1000 nm principal component analysis was used to remove outliers followed by spectra pre-treatment. The best prediction model was achieved for soluble solids with the regression coefficient values of 0.91 for calibration and 0.88 for validation followed by titratable acidity (0.71 and 0.78) and antioxidant activity (0.68 and 0.62). In addition an excellent correlation was observed between spectra and days before harvest (R2 of 0.98 for calibration and prediction models) indicating that is possible to relate spectra changes with ripening, leading also to the effective discrimination of the fruits from the different harvest times. The results showed that this technique may be a valid support to select the optimal harvest time also based on the prediction of the maturity related constituents

Effect of wounding intensity on physiological and quality changes of strawberry fruit

Wounding makes fresh-cut product more perishable than whole fruit. The effect of wounding intensity on respiration rate and nutritional quality of fresh-cut ‘Candonga’ strawberries was investigated. Fruit were submitted to six levels of cutting intensity - whole fruit (WHO), 4, 16, 64, and 128 pieces and chopped (CHO) samples. Respiration rate, and the main nutritional parameters were evaluated at the processing day and after 2 days of storage at 5°C. Results showed that wounding intensity significantly influenced respiration rate, ascorbic and dehydroascorbic acids, total phenolic content, and antioxidant capacity. Respiration rate increased with wounding intensity up to the level of 64 pieces (10.01 µg kg-1 s-1) compared to WHO (5.5 µg kg-1 s-1) and then decreased in the CHO samples (2.81 µg kg-1 s-1). At Day 2, the stress caused by the high intensity of cutting (64 pieces and CHO) induced a higher degradation of ascorbic acid, phenolic compounds, and antioxidant capacity. Stress-related changes decrease when the wounding damage was so high that it completely compromises the functionality of the cells (from 64 pieces up). These results should be considered for processing and packaging optimization of minimally processed strawberries-based products

Fluorescent Membrane Tension Probes for Early Endosomes

Fluorescent flipper probes have been introduced recently to image membrane tension in live cells, and strategies to target these probes to specific membranes are emerging. In this context, early endosomes (EE) targeting without use of protein engineering is especially appealing because it translates into a fascinating transport problem. Weakly basic probes, commonly used to track inside acidic late endosomes and lysosomes, are poorly retained in EE because they are sufficiently neutralized in weakly acidic EE, thus able to diffuse out. Here, we disclose a rational strategy to target EE using a substituted benzylamine with higher pK a as a head group of the flipper probe. The resulting EE flippers are validated for preserved mechanosensitivity, ready for use in biology, particularly to elucidate the mechanics of endocytosis

Dithienothiophenes at Work: Access to Mechanosensitive Fluorescent Probes, Chalcogen-Bonding Catalysis, and Beyond

In this review, the multifunctionality of dithieno[3,2-b:2′,3′-d]thiophenes (DTTs) is covered comprehensively. This is of interest because all involved research is very recent and emphasizes timely topics such as mechanochemistry for bioimaging or chalcogen bonds for catalysis and solar cells and because the newly emerging privileged scaffold is embedded in an inspiring structural space. At the beginning, DTTs are introduced with regard to nomenclature, constitutional isomers, and optoelectronic properties. The structural space around DTTs is mapped out next with regard to heteroatom substitution in the bridge and core, covering much of the periodic table, eccentric heteroatom doping, and bridge expansions. After a brief summary of synthetic approaches to the DTT scaffold, chalcogen bonds are introduced as, together with redox switching and turn-on fluorescence, one of the three conceptual foundations of the most multifunctionality. Realized functions cover anion binding, transport (ion carriers, ion channels), catalysis, and the first fluorescent probes to image physical forces in living cells. The appearance of DTTs in many other photosystems covers push–pull systems for nonlinear optics and dye-sensitized solar cells, DTT polymers in light-emitting diodes, organic field-effect transistors and organic photovoltaics, DTT self-assembly and templated assembly into thin films and fluorescent fibers, also within cells, and the integration of DTTs into photochromes and biaromatics that violate the Hückel rule

Italian family paediatricians’ approach and management of celiac disease: a cross-sectional study in Puglia Region, 2012

BACKGROUND: Celiac disease (CD) is a chronic autoimmune illness of the small intestine triggered by gluten consumption in genetically predisposed individuals. CD presentation is not limited to the gastrointestinal tract and it is still under-diagnosed. Complete resolution of clinical manifestations follows if a gluten-free diet is adopted. In western countries, CD prevalence is approximately 1%. Age of onset is often between 6 months and 7 years.We assessed the approach to diagnosis and management of celiac patients by the paediatricians in Puglia Region, Italy. METHODS: We conducted a cross-sectional survey among the 589 Apulian Family Paediatricians (FPs) during January 2011-January 2012 using a self-administered web-based standardized questionnaire including self-assessment of their knowledge, diagnostic path and type of management they would follow for CD, clinical information on their celiac patients. We assessed associations among the explored variables by defining double-entry contingency tables and calculating Odds Ratio (OR) with 95% Confidence Intervals (CIs). RESULTS: The 218 (37%) FPs participating in the study reported 1,020 CD patients (representing approximately 1% of the child population covered by the enrolled FPs). Of them, 55% were female; 45% were aged 5-10 years. Weight loss and stunting were the main reported symptoms at diagnosis (41%). The majority (98%) of FPs requested anti-transglutaminase antibody (tTG-Ab) titres for CD diagnosis. Approximately 78% of FPs recommended gluten introduction in the diet of infants at the age of 6 months; 12% and 8% recommended introduction of gluten before and after 6 months of age respectively.The degree of knowledge for either CD diagnosis making process or CD related diseases was medium/high in 97% and 82% of the participating FPs respectively. FPs (83%) who had a medium or high degree of knowledge of CD patients' diet were more likely to experience low or no difficulty in providing their patients with dietary advices (OR:5.5;95%CI:1.7-17.5). CONCLUSIONS: Apulian FPs report a good degree of knowledge of CD, its diagnosis and its management. We will diffuse results and recommendations to all paediatricians in the Region. Actions aiming to continued education on CD in medical under and postgraduate trainings are crucial to prevent under-diagnosis

Farà strada il clone di Victoria ad acino allungato?

Tipica della tradizione produttiva pugliese, l’uva da tavola precoce Victoria ha generato un clone mutato con differente morfologia del grappolo, ad acino più lungo ed attraente. Basterà per rilanciare un prodotto di qualità, ma troppo distante dai gusti e dalle modalità di acquisto del consumatore di oggi

General, Mild, and Metal-Free Synthesis of Phenyl Selenoesters from Anhydrides and Their Use in Peptide Synthesis

A mild, practical, and simple procedure for phenyl selenoesters synthesis from several anhydrides and diphenyl diselenide was developed. This transition-metal-free method provides a straightforward entry to storable Fmoc-amino acid selenoesters which are effective chemoselective acylating reagents. An application to oligopeptide synthesis was illustrated