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In the northeast of Portugal there is a tendency to introduce irrigation system on the chestnut orchards but the effect of irrigation on the chestnut’s quality has not been studied yet. This study aims to evaluate the effect of irrigation on the ‘Judia’ cultivar chestnuts quality concerning its chemical composition, fruit size and tastiness. Three treatments were applied during 2015 and 2016: the drip system, the micro-sprinkler system and a non-irrigated treatment. In both years the bigger chestnuts and production were always present in irrigated treatments. Significant differences among treatments were found in ashes, starch, soluble sugars, and crude protein contents in 2015, but in 2016 no significant differences were found. Moreover, the non-irrigated chestnuts were the sweetest but with smaller calibre. The chestnuts from micro-sprinkler were the firmest and they were as sweet as the drip's chestnuts. Results suggest that irrigation, namely with sprinkler system, valorise the chestnuts by increasing its size and keeping its nutritional value and its sensory quality. [ABSTRACT FROM AUTHOR]

International recommendations establish that 90 Sr + 90 Y clinical applicators have to be calibrated in order to determine the absorbed dose rates in the case of the sources that do not have original calibration certificates, or to update the absorbed dose rates presented in the source certificates. Following these recommendations, a postal dosimetric system was developed to calibrate clinical applicators using two luminescent techniques: thermoluminescence (TL) and optically stimulated luminescence (OSL). In this work, Al 2 O 3 :C commercial detectors were characterized and their TL and OSL responses were analyzed. The results showed the efficiency and the optimal behavior of this material in beta radiation beams. After characterization, the system was sent to the Federal University of Sergipe (UFS), Brazil, for calibration of five 90 Sr + 90 Y clinical applicators, where the detectors were irradiated and returned to IPEN, for their evaluation and determination of the absorbed dose rates. A comparison between these absorbed dose rates and those adopted by the UFS as original was made; the differences obtained were within those of other studies, and they demonstrated the usefulness of the system. [ABSTRACT FROM AUTHOR]

Al 2 O 3 :C is the best material example that presents OSL response and adequate dosimetric behaviour for OSL dosimetry. It was the first commercial material manufactured for use in personal monitoring based on an OSL reader system from Landauer. The purpose of this paper was to report the results of optical fading experiments for the nanoDot commercial OSL detectors (Al 2 O 3 :C), provided by Landauer Inc. Five groups of different experimental conditions were formed with all detectors, exposing them to fluorescent and semiconductor light sources and to sun light. The loss of OSL signal when the detectors are kept open, was verified, which was already expected, but a loss in the OSL signal even when the detectors are exposed to light and covered with the manufacturer plastic protection are also revealed. The results show also that the use of Mylar filters can delay the OSL fading of the detectors. [ABSTRACT FROM AUTHOR]

Abstract: Beta radiation emitters have been intensively used in therapeutic protocols, causing the increase of the radiation exposure of the workers. The thermoluminescent (TL) technique is largely utilized for the monitoring of beta radiation doses of workers. However, recently, the optical stimulated luminescence (OSL) technique has been shown useful for individual dosimetry and for beta radiation. In this study, the results obtained using Al2O3:C (OSL) and CaSO4:Dy (TL) detectors to measure beta absorbed doses inside a glove box at a radiopharmacy laboratory were compared. [Copyright &y& Elsevier]

Chestnut orchards are facing new limitations due to scarce of soil water during summer times, mainly attributed to the low precipitation amount typically occurred on such period. The present study aims to define a methodology to improve in a smart way the utilization of water on chestnut irrigation. Based on leaf gas exchanges parameters, there is done a transposition for the soil water content and matric potential, to allow an optimization of the irrigation scheduling in chestnut trees. Trial was installed in a loamy soil at the northeast of Portugal between 2013 and 2016 with micro-sprinkler and drip irrigation system. Stem water potential, photosynthetic rate, soil water content and soil water potential were monitored during the vegetative cycle (June–October). The stem water potential was dependent on air’s temperature and soil moisture. The higher photosynthetic rate (9–11 μmolCO 2 ·m −2  s −1 ) was reached when midday stem water potential ranged between −1.2 to −0.5 MPa and the regression between stem water potential and soil water content on the top 10–40 cm of soil was of r 2  = 0.38. According to these, it was admissible to trigger irrigation when the probe registers 16% and watering must keep soil’s moisture near 23%. The regression between stem and soil water potential was of r 2  = 0.43 and irrigation scheduling may be triggered when ‘Watermark’ sensor at 30–60 cm soil depth is above −100 cbar to promote good tree water status although this last is air temperature dependent. [ABSTRACT FROM AUTHOR]

Bacterial pathogens must adapt/respond rapidly to changing environmental conditions. Ribonucleases (RNases) can be crucial factors contributing to the fast adaptation of RNA levels to different environmental demands. It has been demonstrated that the exoribonuclease polynucleotide phosphorylase (PNPase) facilitates survival of Campylobacter jejuni in low temperatures and favors swimming, chick colonization, and cell adhesion/invasion. However, little is known about the mechanism of action of other ribonucleases in this microorganism. Members of the RNB family of enzymes have been shown to be involved in virulence of several pathogens. We have searched C. jejuni genome for homologues and found one candidate that displayed properties more similar to RNase R (Cj-RNR). We show here that Cj-RNR is important for the first steps of infection, the adhesion and invasion of C. jejuni to eukaryotic cells. Moreover, Cj-RNR proved to be active in a wide range of conditions. The results obtained lead us to conclude that Cj-RNR has an important role in the biology of this foodborne pathogen. [ABSTRACT FROM AUTHOR]

Molecular hydrogen (H2) obtained from biological sources provides an alternative to bulk chemical processes that is moving towards large-scale, economical generation of clean fuel for automotive engines. This opinion article examines recent improvements in H2 production by wild and mutant strains of Chlamydomonas reinhardtii – the green microalga currently considered the best eukaryotic H2 producer. Here, we review various aspects of genetic and metabolic engineering of C. reinhardtii, as well as of process engineering. Additionally, we lay out possible scenarios that would lead to more efficient research approaches in the near future, as part of a consistent strategy for sustainable biohydrogen supply. [ABSTRACT FROM AUTHOR]

• Effect of agricultural practice on raspberry phytochemical composition was studied. • Raspberry phytochemical composition depends on the cultivar and agricultural practice. • Polyphenols increased for the 'Kweli' cultivar under organic agricultural practice. • Polyphenols decreased for the 'Tulameen' cultivar under organic agricultural practice. Raspberries are rich in polyphenols but the impact of organic versus conventional agricultural practices on their phytochemical composition is not well known. This study aimed to analyse and compare the polyphenol accumulation in raspberries grown under both agricultural practices in the same edaphoclimatic conditions. Two raspberry cultivars 'Kweli' and 'Tulameen' were used. Under organic agricultural practices, the polyphenols levels increased for the 'Kweli' cultivar but decreased for the 'Tulameen' cultivar. 'Tulameen' cultivar grown under conventional agricultural practices contained higher anthocyanins levels than grown under organic agricultural practices while for the 'Kweli' cultivar no significant differences were observed between the two agricultural practices. 'Kweli' cultivar presented a significantly higher amount of ellagitannins and ellagic acid derivatives when compared to the 'Tulameen' cultivar under both agricultural practices. The effect of the agricultural practices on the raspberries' chemical profile was dependent on the cultivar and cannot be generalised. [ABSTRACT FROM AUTHOR]