4,874 research outputs found
TRS-measurements as a nondestructive method assessing stage of maturity and ripening in plum (Prunus domestica L.)
n plum fruit with dark red or blue blush colour covering the whole fruit, the change in ground colour from green to yellow during maturation and ripening is masked. Hence, the maturity stage is difficult to judge. Time-resolved reflectance spectroscopy (TRS) has been used as a nondestructive method to assess changes in important internal quality factors in ‘Jubileum’ plums (Prunus domestica L.). Absorption coefficients (µa) and scattering coefficients (µs) were measured at both 670 and 758 nm during 5 days of storage. The changes in soluble solids content, titratable acidity and firmness were as expected. No change in soluble solids content was observed, while the plums became less acid and softer during storage. The TRS-measurements of plums indicated that TRS could give interesting information on internal quality factors in plums as the absorption at 670 nm was closely related to firmness, TA and TSS at the time of picking. Absorption at 758 nm was more closely related to the quality parameters after storage. The study did not indicate that scattering could be used in assessing maturity stage in plum
Optical Absorption and Scattering Phenomena in 'Jubileum' Plums in Relation to Their Colour Properties
Absorption and scattering of laser light pulse passing through the fruit determine among others, the optical properties of the product. Efforts have been made in the recent past to utilize innovative techniques such as time-resolved reflectance spectroscopy (TRS) to study the quality aspects of different fruit such as nectarines. These optical properties have been well related to firmness, sugars, acids and other quality attributes. TRS measurements were performed on ‘Jubileum’ plums at two different wavelengths: 670 nm and 758 nm. The fruit were harvested in Norway and brought to Italy under protected conditions. After sorting the fruit by size, TRS measurements were made and the fruit were randomized for different examinations of quality aspects. It was observed that the absorption coefficient (µa) increased for both wavelengths as ripening progressed towards the melting stage of the fruit. The µa values at 670 nm were higher than those at 758 nm. The higher rate in the µa was distinguishable from the third day onwards as the fruit ripened. Similarly, it was interesting to note that the internal colour measured after destructing the fruit related well with the TRS absorption coefficient (µa), i.e., a decrease in the CIE L* (towards darker region) and b* (towards blue) value along with an increase in a* (towards red) from third day of storag
Unsupervised analysis of small animal dynamic Cerenkov luminescence imaging
Clustering analysis (CA) and principal component analysis (PCA) were applied to dynamic Cerenkov lumi- nescence images (dCLI). In order to investigate the per- formances of the proposed approaches, two distinct dy- namic data sets obtained by injecting mice with 32 P-ATP and 18 F-FDG were acquired using the IVIS 200 optical im- ager. The k-means clustering algorithm has been applied to dCLI and was implemented using interactive data lan- guage 8.1. We show that cluster analysis allows us to ob- tain good agreement between the clustered and the corre- sponding emission regions like the bladder, the liver, and the tumor. We also show a good correspondence between the time activity curves of the different regions obtained by using CA and manual region of interest analysis on dCLIT and PCA images. We conclude that CA provides an auto- matic unsupervised method for the analysis of preclinical dynamic Cerenkov luminescence image data. C 2011 Society of Photo-Optical Instrumentation Engineers (SPIE). (DOI: 10.1117/1.3663442
Photodynamic therapy using Cerenkov and radioluminescence light
In this short review the potential use of Cerenkov radiation and radioluminescence as internal sources for Photodynamic therapy (PDT) is discussed. PDT has been developed over the course of more than 100 years and is based on the induced photo conversion of a drug called photosensitizer (PS) that triggers the production of cytotoxic reactive oxygen species (ROS) leading to the killing of the cells. In order to overcome the problem of light penetration in the tissues, different solutions were proposed in the past. The use of radioisotopes like: F-18, Cu-64, Y-90, Lu-177 as internal light sources increase the light fluence at the PS compared to an external source, resulting in a larger cytotoxic effect
Health Information Systems: Systems Closed to Social Citizens. One Challenge in Reducing Inequalities in Local Management.
Objective: To reflect on the use of health information systems (SIS in Spanish and Portuguese) and their impact on reducing inequalities in health care from the local administration
The unseen effect of pesticides: The impact on phytobiota structure and functions
In the last years, the diffusion and implementation of next-generation
sequencing and the reduction of costs raised the interest in phytyobiome
studies allowing to dissect the ecological interactions regulating the holobiont.
Indeed, crop plants are associated with a wide diversity of microorganisms in all
their parts. Crop microbiota influences plant phenotype, growth, yield and
quality by contributing to plant resistance toward diseases, plant adaptation to
abiotic stresses, and plant nutrition. The association between terrestrial plants
and microbes developed at least 460 million years ago, as suggested by the
fossil evidence of the earliest land plants, indicating the essential role of
microbes for plants. Recent studies indicate that plants actively recruit
beneficial microorganisms to facilitate their adaptation to environmental
conditions. Cultivation methods and disease control measures can influence
plant microbiome structure and functions. Both pesticide and biological
control agent applications may alter the biodiversity inside the phytobiota
and suppress beneficial functions. Nonetheless, to date, the effects of disease
control measures on phytobiota and their possible side consequences on plant
growth, crop productivity and quality remain a neglected field of study. The
present work summarizes the known effects on phytobiota providing evidence
about the role of plant microbial community in determining the overall efficacy
of the applied control measure and suggests that future studies on plant
disease control consider also the microbe-mediated effects on plant fitness
Monte Carlo simulations support non-Cerenkov radioluminescence production in tissue
There is experimental evidence for the production of non-Cerenkov radioluminescence in a variety of materials, including tissue. We constructed a Geant4 Monte Carlo simulation of the radiation from P32 and Tc99m interacting in chicken breast and used experimental imaging data to model a scintillation-like emission. The same radioluminescence spectrum is visible from both isotopes and cannot otherwise be explained through fluorescence or filter miscalibration. We conclude that chicken breast has a near-infrared scintillation-like response with a light yield three orders of magnitude smaller than BGO
CO2 capture in cement plants by "Tail-End" Calcium Looping process
Abstract In this work the integration of the Calcium-Looping (CaL) process, used as a post-combustion CO2 capture system, into a cement kiln was analyzed by means of process simulations. The results show that capture efficiencies of about 90% can be achieved with operating conditions of CaL reactors similar to those for power generation applications. The integration of the CaL process increases the fuel consumption of the cement kiln, but the additional primary energy introduced for sustaining this CO2 capture process can be efficiently exploited for raising HP steam and producing electricity in a Rankine cycle
Giuseppe Rensi e le radici greche dello scetticismo
Dopo aver sinteticamente presentato le principali caratteristiche della vicenda bio-bibliografica di Giuseppe Rensi, questo articolo cerca di ricostruire la sua analisi del contributo greco alla lunga storia dello scetticismo. Benché in molti casi attento e storicamente attendibile, l’approccio di Rensi mira a inserire un tale contributo in una prospettiva più ampia, utile per rinforzare la sua originale idea di ciò che dovrebbe essere considerata la genuina (e produttiva) essenza degli sforzi scettici, intesi come il più potente strumento contro ogni pretesa filosofica ‘assolutistica’
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