•Accurate NIR calibration models were obtained for main quality indexes of apples.•Total phenolics and antioxidant activity of apples could be predicted by NIR-based models.•Classification models ...were able to discriminate apple lots on the basis of storage time.
Apples can be stored for long time under controlled temperature and atmosphere conditions, and therefore, non-destructive and rapid tools are required to assess fruit quality and to monitor changes during the postharvest period. The aim of this study was to evaluate the feasibility of NIR spectroscopy to optimize postharvest apple management and to follow changes in fruit quality during storage. An FT-NIR system operating in diffuse reflectance in the range 12,500–3600cm−1 was used to evaluate the physico-chemical (dry matter, soluble solids, colour and firmness) and some nutraceutical characteristics (total phenolics, total flavonoids and antioxidant activity) of ‘Golden Delicious’ apples, which were stored for about six months at 1°C in controlled atmosphere, over two subsequent years. Spectral data were elaborated by PLS regression and LDA classification techniques. Good correlation models between spectral data and chemical and physical parameters were obtained for soluble solids, a* colour coordinate and firmness (0.81<R2<0.90 in calibration and 0.79<R2<0.89 in cross validation). Even higher correlation values (0.89<R2<0.95 in calibration and 0.86<R2<0.92 in cross validation) were obtained for indexes correlated to the antioxidant capacity of apples. The classification technique Linear Discriminant Analysis was applied to spectral data, in order to discriminate apples on the basis of storage time. Average correct classification was higher than 93% in validation and close to 100% in calibration, indicating high potential of NIR spectroscopy for the estimation of storage time of apple lots.
Ship emissions are a growing concern, especially in coastal areas, for potential impacts on human health and climate. International mitigation strategies to curb these emission, based on low-sulphur ...content fuels, have proven useful to improve local air quality. However, the effect on climate forcing is less obvious. Detailed information on the influence of shipping to particles of different sizes is needed to investigate air quality and climate interaction. In this work, the contributions of maritime emissions to atmospheric concentrations of gaseous pollutants (NO, NO2, SO2, and O3) and of particles (sizes from 0.009 μm to 30 μm) were investigated considering manoeuvring (arrival and departure of ships) and hotelling phases (including loading/unloading activities). Results showed that the size distributions of shipping contributions were different for the two phases and could be efficiently described, using measured data, considering four size-ranges. The largest contribution to particles concentration was observed for Dp < 0.25 μm, however, a secondary maximum was observed at Dp = 0.35 μm. The minimum contribution was observed at Dp around 0.8–0.9 μm with a negligible contribution from hotelling for size range 0.4–1 μm. The comparison of 2012 and 2014 datasets showed no significant changes of gaseous and particulate pollutant emissions and of the contribution to particle mass concentration. However, an increase of the contribution to particle number concentration (PNC) was observed. Results suggested that harbour logistic has a relevant role in determining the total impact of shipping on air quality of the nearby coastal areas. Additionally, future policies should focus on PNC that represents an important fraction of emissions also for low-sulphur fuels. DOAS remote sensing proved a useful tool to directly measure NO2 and SO2 ship emissions giving estimates comparable with those of emission inventory approach.
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•Impacts of shipping to gases and particles between 0.009 and 30 μm were investigated.•DOAS remote sensing proven efficient to evaluate emission rates of SO2 and NO2.•Maximum impact was on ultrafine particles and a minimum was observed at Dp≅0.8–0.9 μm.•Size distributions of impacts were different for hotelling and manoeuvring phases.•Impacts to mass concentrations were influenced by particles up to Dp≅8–9 μm.
The non-native invasive anuran
Lithobates catesbeianus
is presently distributed in Brazil, especially in the Atlantic Rainforest biodiversity hotspot. Here, we use a maximum entropy ecological niche ...modeling algorithm (i) to model the North American native geographic distribution of this species and (ii) to project that model onto the whole of Brazil. After applying a threshold value that balances commission and omission errors, the projection results suggested high probabilities of occurrence mostly in southern and southeastern Brazil. We also present the first report on the species known distribution in Brazil, showing good agreement with model predictions. If the predictive map is interpreted as depicting invasiveness potential of
L. catesbeianus
, strategies to prevent further invasion in Brazil should be focused especially in the Atlantic Rainforest biodiversity hotspot.
The Plio–Pleistocene refugia hypothesis recently gained support in explaining Brazilian Atlantic Forest megadiversity from combined analyses of species paleodistributions and genetic diversity. Here ...we examine genetic differentiation and historical distributions in the
Rhinella crucifer group of toads, endemic to and widely distributed within this biome. We analyzed sequences of mitochondrial (control region, ND1, and ND2) and nuclear (β-crystallin and rhodopsin) DNA markers from 65 individuals representing five species. We found deep structure across the range at mitochondrial markers; genetic diversity is geographically structured in four main haplotype clades with the oldest divergence, dated to the Pliocene, between the southernmost populations and other regions of the species’ range. Remaining populations are distributed in haplotype clades that may have diverged throughout the Pleistocene. Our paleoecological distribution models support a scenario of habitat fragmentation associated with glacial cycling, but we found limited congruence of phylogeographic patterns with the refugia. We found that some genetic breaks geographically coincide with putative barriers associated to neotectonic activity, but finer-scale sampling will be necessary to test the relative importance of distinct isolation mechanisms. Overall, the data refute the recently proposed hypothesis of a southern Holocene colonization of the Atlantic Forest from northern refugia, suggesting instead persistence of forested habitats in the south. Our unexpected results underscore the need to consider distinct organismal histories in planning biome-level conservation. We discuss species correspondence to clades recovered in our phylogenetic analyses.
The effect of a steam blanching preconditioning step was investigated on the chemical, nutraceutical and morphological characteristics of osmo-dehydrated blueberries (Vaccinium corymbosum L.) in ...sucrose or glucose/fructose osmotic solutions. Mass transfer phenomena (solid gain, water loss and sugar gain) were monitored into the samples at intervals over a 24-h period of osmodehydration. The antioxidant capacity of untreated and osmo-dehydrated fruits was evaluated by total phenolics, total and individual anthocyanins and antioxidant activity (amperometric method), while colorimetric (luminance) and morphological (area, shape factor, fractal dimension) characteristics of the berries were determined by image-analysis technique. Results showed that the blanching step increased mass transfer phenomena in the course of the osmodehydration treatments (approx +55% solid gain and +33% water loss) and reduced the loss of phenolic compounds, improving the retention of antioxidant capacity in the final product (from approx 66.9–56.9% in not blanched berries to 88.6–95.7% in blanched ones). Blanched berries had also deeper colour and smoother surface. Slight differences in mass balances and in the final composition of berries could be ascribed to the kind of osmotic solution used.
► Influence of steam-blanching pretreatment on the quality of osmodehydrated blueberries ► Mass transfer phenomena are enhanced by a steam blanching pretreatment ► Higher sugar gain is obtained in glucose/fructose and higher water loss in sucrose ► The loss of phenolic antioxidants is partially prevented by berry blanching ► Blanched osmo-dehydrated berries have deeper colour, higher turgidity and smoother surface
Application of non destructive methods for the monitoring of red wine fermentation in correlation with the evolution of chemical parameters.
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► We monitored time-related changes in red ...wine fermentation process. ► NIR and MIR spectroscopies, electronic nose and tongue were applied. ► Data were kinetically modelled to identify critical points during fermentation. ► NIR, MIR electronic nose and tongue were able to follow the fermentation process. ► The models agreed with the evolution of chemical parameters.
Effective fermentation monitoring is a growing need due to the rapid pace of change in the wine industry, which calls for fast methods providing real time information in order to assure the quality of the final product. The objective of this work is to investigate the potential of non-destructive techniques associated with chemometric data analysis, to monitor time-related changes that occur during red wine fermentation. Eight micro-fermentation trials conducted in the Valtellina region (Northern Italy) during the 2009 vintage, were monitored by a FT-NIR and a FT-IR spectrometer and by an electronic nose and tongue. The spectroscopic technique was used to investigate molecular changes, while electronic nose and electronic tongue evaluated the evolution of the aroma and taste profile during the must-wine fermentation. Must-wine samples were also analysed by traditional chemical methods in order to determine sugars (glucose and fructose) consumption and alcohol (ethanol and glycerol) production. Principal Component Analysis was applied to spectral, electronic nose and electronic tongue data, as an exploratory tool, to uncover molecular, aroma and taste modifications during the fermentation process. Furthermore, the chemical data and the PC1 scores from spectral, electronic nose and electronic tongue data were modelled as a function of time to identify critical points during fermentation. The results showed that NIR and MIR spectroscopies are useful to investigate molecular changes involved in wine fermentation while electronic nose and electronic tongue can be applied to detect the evolution of taste and aroma profile. Moreover, as demonstrated through the modeling of NIR, MIR, electronic nose and electronic tongue data, these non destructive methods are suitable for the monitoring of must-wine fermentation giving crucial information about the quality of the final product in agreement with chemical parameters. Although in this study the measurements were carried out in off-line mode, in future these non destructive techniques could be valid and simple tools, able to provide in-time information about the fermentation process and to assure the quality of wine.
This work is focused on some properties of various dried tomato products (tomato pulp, tomato halves and insoluble solids-rich tomato), useful to optimize drying processes. Adsorption and desorption ...isotherms at 20°C of these products were measured and modelled by the Guggenheim–Anderson–de Boer (GAB) equation. Insoluble solids-rich tomato was the least hygroscopic of all tomato products. Tomato products were air-dried in a pilot plant and the drying kinetics was modelled. The mass transfer equation for drying of thin slabs, modified to include shrinkage of samples during drying, was successfully applied to experimental data. Apparent water diffusivity values ranged from 2.3×10
−9 to
9.1×10
−9
m
2
/s as a function of the structure of tomato products. The lycopene and ascorbic content and the antioxidant activity of hydrophilic and lipophilic extracts were measured both on fresh and dried tomato products. Interesting properties of insoluble solids-rich tomato were evidenced: it had the highest lycopene content (ca. 12,000 mg/kg dm) and lipophilic antioxidant activity (ca.
400I
50,
μg
dm
) of all tomato products.
We here examine species distribution models for a Neotropical anuran restricted to ombrophilous areas in the Brazilian Atlantic Forest hotspot. We extend the known occurrence for the treefrog
...Hypsiboas bischoffi (Anura: Hylidae) through GPS field surveys and use five modeling methods (BIOCLIM, DOMAIN, OM-GARP, SVM, and MAXENT) and selected bioclimatic and topographic variables to model the species distribution. Models were first trained using two calibration areas: the Brazilian Atlantic Forest (BAF) and the whole of South America (SA). All modeling methods showed good levels of predictive power and accuracy with mean AUC ranging from 0.77 (BIOCLIM/BAF) to 0.99 (MAXENT/SA). MAXENT and SVM were the most accurate presence-only methods among those tested here. All but the SVM models calibrated with SA predicted larger distribution areas when compared to models calibrated in BAF. OM-GARP dramatically overpredicted the species distribution for the model calibrated in SA, with a predicted area around 10
6
km
2 larger than predicted by other SDMs. With increased calibration area (and environmental space), OM-GARP predictions followed changes in the environmental space associated with the increased calibration area, while MAXENT models were more consistent across calibration areas
. MAXENT was the only method that retrieved consistent predictions across calibration areas, while allowing for some overprediction, a result that may be relevant for modeling the distribution of other spatially restricted organisms.
The multipurpose ultraviolet-visible (UV-Vis) remote sensing equipment SPATRAM (SPectrometer for Atmospheric TRAcers Monitoring) is a scanning spectrometer for measurement of electromagnetic ...radiation in the 250-950 nm spectral range. In this paper SPATRAM will be presented and new solutions will be discussed. The monochromator is based on the one installed in GASCOD (Gas Analyzer Spectrometer Correlating Optical Differences) developed during the 1990s. The most important improvements of SPATRAM relative to GASCOD are: (i) the wider spectral range scanned, allowing for the detection of more atmospheric compounds than with GASCOD; (ii) an increased number of inputs, resulting in the possibility of quasi-simultaneous measurements from different optical devices; (iii) the focusing optic system, which permits a simple optical alignment procedure and low cost; (iv) electronic self-thermoregulation, allowing for reliable spectral measurements unaffected by mechanical deformation caused by variation of temperature; (v) adoption of a CCD sensor, resulting in an increase of equipment sensitivity and therefore an enhancement in time resolution of the measurements; (vi) the use of an advanced CPU and a standard OS, guaranteeing full stability of the equipment; and (vii) the development of a new software tool for complete control of the whole instrument and for pre-processing of the measured data.
This paper presents an evaluation of the nitrogen dioxide (NO₂) trend inferred from UV–visible zenith-sky measurements performed at the ‘Ottavio Vittori’ ground-based research station ...(http://www.isac.cnr.it/cimone) at Monte Cimone (44.18° N, 10.7° E, 2165 m above sea level (a.s.l.)). Experimental data series are obtained from the measured spectra adopting a retrieval procedure according to differential optical absorption spectroscopy (DOAS) methodology. Data series cover the period from 1993 to 2009, with limited interruptions due to technical maintenance of the instrument or poor meteorological conditions. The NO₂ trends are calculated with a linear regression model considering different factors assumed to contribute to NO₂ atmospheric content. Before running the model, a procedure for data quality control was applied to reduce or exclude the influence of measurements affected by poor meteorological conditions or the vertical transport of polluted air masses from the lower troposphere. The negative trends obtained for sunrise (a.m.) and sunset (p.m.) NO₂ measurements are in good agreement with previous studies accomplished for ground-based stations in the northern hemisphere.
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