ABSTRACT
Electrical resistance changes in different organs of four olive tree (Olea europaea L.) varieties, characterized by different tolerance to chilling and freezing, were examined, during ...exposure to low temperature. Apparent critical temperatures (CT) and freezing temperatures (Tfr) were identified on the basis of the electrical resistance changes. Both temperatures were lower for the more chilling‐tolerant genotypes. From the apparent critical temperatures, the absolute critical temperature (CTabs) and the time delay of the chilling signal transduction process were calculated. In shoots, CTabs varied from 8·8 °C for Ascolana (chilling‐tolerant variety) to 13·6 °C for Coratina (chilling‐sensitive variety). The magnitude of the transduction time was very similar (about 2 min) for the three genotypes that are more sensitive to chilling, whereas it was significantly higher (about 3 min) for the most tolerant genotype. Different freezing temperatures were observed for different organs. It would appear from this experiment that the order of sensitivity is roots > leaves > shoots > vegetative buds. Accord was found between the absolute critical temperature of electrical resistance and the critical temperature of membrane potential. The occurrence of electrical resistance changes in the tissues of the olive trees exposed to low temperature suggests the use of this experimental procedure as a quick, easy and non‐destructive tool to screen plant tissues for chilling tolerance. The strong dependence of the electrical resistance on low temperature, and the critical temperature of around 10 °C, can yield interesting information about the lowest thermal limits for the continuation of normal physiological processes and therefore about the adaptability of plants to particular environments.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
We report on the analysis of a fast coronal mass ejection (CME)-driven shock observed on 2002 July 23 with the Ultraviolet Coronagraph Spectrometer (UVCS) on board the Solar and Heliospheric ...Observatory (SOHO). The CME was first detected in white light by the Large Angle and Spectrometric Coronagraph Experiment (LASCO), and shock-associated type II metric emission was recorded by several ground-based radio spectrographs. The evolution of the excess broadening of the O vi lambda1032 line profiles observed by UVCS at 1.63 R sub(image) is consistent with the passage of a CME-driven shock surface enveloping a bubble-type, conically expanding CME, and its dynamics is found to be well associated with the complex, multiple type II radio emission detected in the metric band. Our results suggest that there might be a deficiency of ion heating in the present event with respect to what was observed in previous CME shocks detected by UVCS, and that this paucity might be attributed to different local plasma conditions, such as higher ambient coronal plasma beta . We conclude that plasma beta could be an important parameter in determining the effect of ion heating at collisionless shock fronts in the solar corona.
The analysis of two historical time series of temperature and precipitation in Northeast China, spanning, respectively, 1870-2004 and 1841-2004, performed by continuous wavelet transform and other ...classical and advanced spectral methods, is presented here. Both variables show a particular trend and oscillations of about 85, 60, 35 and 20 years that are highly significant, with a phase opposition at the centennial scale and at the 20-year scale. The analysis of the four temperature series relative to single seasons shows that the 20-year cycle is typical of the summer monsoon season, while the 35-year cycle is most evident in winter. The cycles of ~ 60 years and longer are present in all seasons. The centennial variation of temperature and precipitation describes well the 1970-1980 transition between a period of relatively strong East Asian Summer Monsoon (EASM), corresponding to high precipitation and relatively cool temperatures in Northeast China, and a conditions of weak EASM (low precipitation and warm temperatures). The connection of the detected local variations with large-scale climatic variability is deduced from the comparison with different climatic records (Northern Hemisphere temperature, Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation indexes).
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
To date, the chemical composition and the amount and diversity of volatile organic compounds (VOCs) released by different woody plants samples have been measured and characterized through one of the ...most common techniques, the gas chromatography–mass spectrometry. However, this technique is very time-consuming and requires sample preparation. By contrast, the Proton-Transfer-Reaction Time-of-Flight Mass spectrometry (PTR-ToF-MS) represents an innovative tool able to provide the whole mass spectra of VOCs with short response time, high mass resolution and without sample preparation. This technique is fast, non-invasive, highly sensitive with a rapid detection system and a very low mass fragmentation of the volatile molecules. The goal of this study was to characterize the VOCs profile of different wood sample cores using a PTR-ToF-MS tool and thereafter to assess whether VOC emissions were specific for some groups of trees. VOCs released from core wood samples belonging to 14 different species were analyzed and subsequently, using an advanced multivariate class-modeling approach, the groups (softwood and hardwood) and the different tree species were discriminated. PTR-ToF-MS was able to detect VOCs from wood and to discriminate between hardwood and softwood and among different species. The great potential and the rapidity of this analysis method allow the PTR-ToF-MS to become a commercial standard tool for monitoring VOCs emitted by wood.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The morpho-chemical and aromatic characteristics of four sweet cherry cultivated varieties (Prunus avium L.) grown in the area of Lari (Pisa, Central Italy) were evaluated with the aim to investigate ...their properties, mainly concerning volatile organic compounds (VOCs). Of these, three cultivars (‘Di Giardino’, ‘Di Nello’, and ‘Marchiana’) represent ancient sweet cherries recovered through a private cultivation program (belonging to the group of the so-called ‘Ciliegia di Lari’); their evaluation was compared with the commercial cultivar Ferrovia, highly-prized variety marketed in Italy and abroad. Morpho-chemical analyses highlighted statistical differences among the cultivars under study, mainly on total soluble solids (TSS) and tritatable acidity (TA). Aroma investigation was performed with PTR-ToF-MS (proton transfer reaction - time of flight - mass spectrometer) approach, employed here for the first time in cherry fruits. About 50 VOCs were detected; among them, those belonging to the chemical classes of aldehydes and alcohols were the most represented although with different intensities between samples. Tentative identification of some key VOCs for cherry fruit was also performed and preliminary conclusions on the characterization of ancient and wide spread Italian cultivars were given.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
In this paper we investigate the relationship between type II and coronal transient activity in terms of emission originating from the top or the flanks of a bow/piston shock surface, extending just ...above the coronal mass ejection (CME) leading edge surface. For this purpose, we used ground-based metric type II radio burst observations of twenty-nine events in conjunction with Large Angle and Spectrometric Coronagraph (LASCO/SOHO) and UltraViolet Coronagraph Spectrometer (UVCS/SOHO) observations. With the refined density diagnostic offered by the UVCS instrument, we analyzed the type II dynamics in conjunction with the associated CME dynamics. Although we found some correlation, in all but a few cases the coronal transients appeared to lead the type II emission locations by several minutes, in apparent disagreement with a CME-driven origin interpretation. By applying a simple model, we found however that a piston-driven origin is certainly viable for all the events under study on the hypothesis that the radio emission originates in discrete locations above the top or the flanks of bow/piston shock surfaces extending just above the transient leading edges.
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FMFMET, NUK, UL, UM, UPUK
Summary
Background
Offspring of women with gestational diabetes (OGD) have greater risk for obesity and impaired metabolic health. Whether impaired metabolic health occurs in the absence of obesity ...is not clear.
Objective
The purpose of this study was to investigate the independent and interactive effects of intrauterine exposure to gestational diabetes and of children's current weight status on their metabolic health.
Methods
Children aged 5–10 years (n = 51) with and without intrauterine exposure to gestational diabetes (OGD vs. offspring of non‐diabetic women CTRL) were grouped into normal weight (body mass index BMI < 85th %) and overweight (BMI > 85th %) according to Centers for Disease Control growth curves. Lipid profile was obtained by fasting blood draw, insulin sensitivity (SI) and secretion by liquid meal tolerance test, and body composition by dual‐energy X‐ray absorptiometry.
Results
Despite similar average BMI percentiles among normal weight OGD versus CTRL, and overweight OGD vs. CTRL, OGD had greater total %fat and trunk fat adjusted for leg fat compared with CTRL (P < 0.05). Overweight children had lower SI (P < 0.05) and greater basal, static, and total insulin secretion independent of SI (P < 0.05). OGD was independently associated with greater static insulin secretion (P < 0.05) and the interaction between OGD and overweight was associated with greater basal insulin secretion independent of SI (P < 0.01). OGD and overweight were each associated with lower high‐density lipoprotein‐cholesterol (HDL‐C) (P < 0.05).
Conclusion
Intrauterine exposure to gestational diabetes was associated with greater central adiposity and insulin secretion, and lower HDL‐C, irrespective of current weight status. Future research should examine respective contributions of the intrauterine environment and of underlying genotype on children's metabolic health.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
The quality of coffee is linked to the aroma created by the chemical reactions that occur during the roasting process. While it is generally thought that roasted coffee is a stable product with a ...relatively long shelf-life, little information is available on the evolution (kinetic) of the volatile organic compounds (VOCs) in the days immediately following the process. The aim of this study is to determine the evolution of VOCs released by coffee beans, on samples of Coffea arabica (three different origins) and Coffea canephora (1 single origin), by using a Proton Transfer Reaction Time-of-Flight Mass Spectrometer (PTR-ToF-MS) 24 hours after roasting, and for the next 9 days. Results confirmed the differences already highlighted in previous studies between the VOCs spectra of the two species. There were also significant differences in the intensity of emissions for the different origins of Coffea arabica, with the highest VOCs amount over time always detected in the Honduras Arabica samples. The involved detected protonated ions were grouped into three classes: compounds (ppbv) present with decreasing quantity; weakly increasing; almost constant trend; or always increasing. A complex dynamic emerged for the different protonated ions over time, which not only affects the mass spectra of the different species but also influences the configuration of the mass spectra of the different geographical zones of production.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
The atmospheric re‐entry domain is a cornerstone of a wide range of space applications, ranging from reusable launcher stages developments, robotic planetary exploration, human space flight, to ...innovative applications such as reusable research platforms for in orbit validation of multiple space applications technologies.
The Intermediate experimental Vehicle (IXV) is an advanced demonstrator which has performed in-flight experimentation of atmospheric re-entry enabling systems and technologies aspects, with significant advancements on Europe's previous flight experiences, consolidating Europe's autonomous position in the strategic field of atmospheric re-entry.
The IXV mission objectives were the design, development, manufacturing, assembling and on-ground to in-flight verification of an autonomous European lifting and aerodynamically controlled reentry system, integrating critical re-entry technologies at system level. Among such critical technologies of interest, special attention was paid to aerodynamic and aerothermodynamics experimentation, including advanced instrumentation for aerothermodynamics phenomena investigations, thermal protections and hot-structures, guidance, navigation and flight control through combined jets and aerodynamic surfaces (i.e. flaps), in particular focusing on the technologies integration at system level for flight, successfully performed on February 11th, 2015.
•Successful European atmospheric re-entry mission.•Inflight qualification of key atmospheric reentry system and technologies.•Un-winged lifting body performances verification.•Ceramic matrix composites performances qualification.•Advanced Guidance Navigation and Control qualification.•Aerothermodynamics phenomena investigation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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