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Fusarium poae is one of the Fusarium species commonly detected in wheat kernels affected by Fusarium Head Blight. Fusarium poae produces a wide range of mycotoxins including nivalenol (NIV). The effect of temperature on colony growth and NIV production was investigated in vitro at 5-40 °C with 5 °C intervals. When the data were fit to a Beta equation (R2 ≥ 0.97), the optimal temperature was estimated to be 24.7 °C for colony growth and 27.5 °C for NIV production. The effects of temperature on infection incidence, fungal biomass, and NIV contamination were investigated by inoculating potted durum wheat plants at full anthesis; inoculated heads were kept at 10-40 °C with 5 °C intervals for 3 days and then at ambient temperature until ripening. Temperature significantly affected the incidence of floret infection and fungal biomass (as indicated by DNA amount) in the affected heads but did not affect NIV content in the head tissue. Inoculation of potted plants with F. poae did not reduce yield.

This paper presents experimental and numerical analyses of a novel high-temperature solar cooling system based on innovative flat-plate evacuated solar thermal collectors (SC). This is the first solar cooling system, including a double-effect absorption chiller, which is based on non-concentrating solar thermal collectors. The aim of the paper is prove the technical and economic feasibility of the system, also presenting a comparison with a conventional technology, based on concentrating solar thermal collectors. To this scope, an experimental setup has been installed in Saudi Arabia. Here, several measurement devices are installed in order to monitor and control all the thermodynamic parameters of the system. The paper presents some of the main results of this experimental campaign, showing temperatures, powers, energies and efficiencies for a selected period. Experimental results showed that collector peak efficiency is higher than 60%, whereas daily average efficiency is around 40%. This prototypal solar cooling system has been numerically analysed, developing a dynamic simulation model aiming at predicting system performance. For a representative operating period, numerical data were compared with the experimental one, showing an excellent accuracy of the model. A similar system, equipped with Parabolic Trough solar thermal collectors (PTC) was also simulated in order to compare the novel solar collectors with such reference technology. For both systems a detailed thermo-economic model has been implemented in order to perform such comparison also from the economic point of view. Results showed that the rated energy performance of the prototypal solar cooling system featuring new collectors is better than that of the reference system. In particular, the difference between the novel and the reference solar cooling system becomes more and more significant, when considering the effects of dust and defocusing related to the tracking mechanism of concentrating collectors in harsh environments. Finally, from the economic point of view, results showed that the novel prototype was able to achieve a good profitability. (C) 2015 Elsevier Ltd. All rights reserved.

The composition of the extender in which semen is diluted before freezing plays a major role in successful cryopreservation of spermatozoa. Substances of high osmolarity, like glycerol, protect sperm cells during the freezing process and energy-rich compounds, like pyruvate provide extra energy during capacitation and fertilization. Since cryopreservation procedures for Buffalo spermatozoa have not been adequately defined, the aim of the study was to improve the survival rate of buffalo (Bubalus bubalis) spermatozoa after cryopreservation by optimizing the timing for adding glycerol and by enriching the cryoprotectant extender with an energy source substrate. Semen was collected with an artificial vagina from 5 bulls and the ejaculates were immediately evaluated for motility, forward progressive motility and for viability, pooled and held at room temperature (28 degrees C) for 1 h. Then aliquots of pooled semen were subjected to dilution and equilibration in triplicate as follows: Experiment 1. Glycerol (3%) in a commercial extender was added to the semen at 28 degrees C and cooled to 5 degrees C for 1 h; then extender with 11% glycerol was added before further equilibration (initial glycerol addition; IGA) and the samples held at 5 degrees C for 1, 3 or 5 additional hours (IGA 1, n = 24; IGA 3, n = 24; IGA 5, n = 24) before freezing. Experiment 2. Glycerol (3%) was added and the mixture brought to 5 degrees C as described above. Then extender with 11% glycerol was added (late glycerol addition; LGA) and after equilibration for 1, 3 and 5 h (LGA 1, n= 24; LGA 3, n = 24; LGA 5, n = 24) the samples were frozen. In Experiments 3 and 4 Na pyruvate (1.25 mM) was added to the extender as described for IGA and LGA above (IPA and LPA samples). The effect of addition time (initial vs late) of glycerol and pyruvate was evaluated by measuring sperm motility, progressively forward motility and viability. After freezing-thawing the percentage of motile spermatozoa was significantly higher (0.001

The growth cycle in nutrient-rich, aquatic environments starts with a diatom bloom that ends in mass sinking of ungrazed cells and phytodetritus. The low grazing pressure on these blooms has been attributed to the inability of overwintering copepod populations to track them temporally. We tested an alternative explanation: that dominant diatom species impair the reproductive success of their grazers. We compared larval development of a common overwintering copepod fed on a ubiquitous, early-blooming diatom species with its development when fed on a typical post-bloom dinoflagellate. Development was arrested in all larvae in which both mothers and their larvae were fed the diatom diet. Mortality remained high even if larvae were switched to the dinoflagellate diet. Aldehydes, cleaved from a fatty acid precursor by enzymes activated within seconds after crushing of the cell, elicit the teratogenic effect. This insidious mechanism, which does not deter the herbivore from feeding but impairs its recruitment, will restrain the cohort size of the next generation of early-rising overwinterers. Such a transgenerational plant-herbivore interaction could explain the recurringly inefficient use of a predictable, potentially valuable food resource--the spring diatom bloom--by marine zooplankton.

All IssuesUp Arrow In This IssueDown Arrow Left ArrowPrevious Article Next ArticleRight Arrow Environmental Engineering Science About This Journal... Subscribe... Buy Article... Emission of Ultrafine Particles from Natural Gas Domestic Burners To cite this article: Patrizia Minutolo, Andrea D'Anna, Mario Commodo, Rocco Pagliara, Giuseppe Toniato, and Claudio Accordini. Environmental Engineering Science. December 2008, 25(10): 1357-1364. doi:10.1089/ees.2007.0188. Published in Volume: 25 Issue 10: December 30, 2008 Full Text PDF (651.1 KB) Full Text PDF with Links (518.5 KB) Author information Patrizia Minutolo Dipartimento di Ingegneria Chimica, Università "Federico II", Napoli, Italy. Istituto di Ricerche sulla Combustione, C.N.R., Piazzale V. Tecchio 80, 80125 Naples, Italy. Phone: +390817682963; Fax: +390815936936. E-mail: minutolo@irc.cnr.it Andrea D'Anna Istituto di Ricerche sulla Combustione, CNR, Napoli, Italy. Mario Commodo Istituto di Ricerche sulla Combustione, CNR, Napoli, Italy. Rocco Pagliara Dipartimento di Ingegneria Chimica, Università "Federico II", Napoli, Italy. Giuseppe Toniato Riello S.p.A., Burner Division, Italy. Claudio Accordini Riello S.p.A., Burner Division, Italy. ABSTRACT An experimental study of the combustion characteristics of new burners used for home and water heating appliances and domestic stove tops is presented with the aim of evaluating the effect of burner configurations and operating conditions on the emissions of ultrafine particles. Advanced in-situ optical diagnostics, based on laser induced emission spectroscopy (LIE), and ex-situ measurements, based on scanning mobility particle size (SMPS) measurements, and particles collection by water-based sampling technique, were used in order to evaluate total particulate concentrations and size distribution functions. For home heating burners, three different configurations, two premixed and one diffusive, were studied under various operating conditions. Measurements showed that particulate matter with diameters in the 1 nm to 10 nm size range is formed. Emitted mass concentration of these compounds were very low, of the order of 0.1 mg/Nm3. They were formed in large number concentrations in the flame region but were also strongly oxidized in the post-oxidation region of the device. On the contrary, a domestic stove top emits a larger amount of very small particles since their post-oxidization is not possible. Soot particles with size larger than 10 nm are not formed in all the examined conditions and burner configurations

The performance of a domestic appliance for wood logs combustion is a function of several variables, such as the geometric design of the appliance and its operating parameters. Among them, air feeding conditions are really decisive if the objective function is the maximization of the heat recovered from flue gases. Therefore, even if pollutant emissions have to be ever considered, the amount of excess air can be seen as a fundamental parameter in the definition of thermal efficiency of the appliance. In this paper the role of this parameter is analysed. The analysis is conducted by linking the results obtained from experimental data, detailed CFD simulations and a simplified mathematical model based on a network of CSTR. The derivation of an idealized schematization of the appliance was essential to realize the role of excess air variations, with more generality than with respect to a specific appliance configuration. Conversely, while the experimental data and CFD results were necessary to derive the simplified model, the indications given by this simplified model were useful to analyze results coming from both experiments and detailed numerical simulations. It has been evidenced the need to distinguish between the role of excess air in the chemical combustion and in the heat recovery in the appliance as well as to quantify the feedback between these two processes.

The convective drying of pine wood cylinders (40 mm diameter) in hot air has been investigated experimentally for conditions reproducing those encountered in the drying section of xed-bed updraft gasiers (nominal velocities of 0.4- 1:2 m=s and maximum air temperatures of 435-600 K). Temperature proles show a drying zone slowly propagating from the heat exposed surfaces towards the inside, whereas the global drying rate presents two maxima, corresponding to moisture evaporation along a thin supercial layer and sample heat-up, respectively. The drying times reproduce trends already known on dependence of the external heating conditions and the initial moisture content. From the quantitative point of view, a moisture content of 50% is observed to delay the particle heating times up to factors of 3-5. Acceptable quantitative agreement is obtained between these measurements and the predictions of a simplied model of moisture evaporation in wood, which can be used to treat single particle e7ects in the more complicated mathematical descriptions of gasier behavior.

In the present study a laminar premixed ethylene flame was doped with different amounts of ethanol in order to understand the influence on biofuels in the total amount of particulate matter and the size distribution functions of the formed carbonaceous particles. Four different flames were investigated: one of pure ethylene as reference and three with an increased amount of ethanol, i.e. 10%, 20% and 30%. The equivalence ratio of the four flames was kept constant at 2.01. The particle size distribution functions were obtained using a nano-Differential Mobility Analyzer (nano-DMA). The results showed a general reduction of the total volume fraction of particulate when ethanol was added. The reduction of the formed particles increased as a function of the amount of ethanol added. The particle size distribution for pure ethylene flame and ethanol doped flames at different heights with the same amount of particles are quite similar. This indicates that in premixed flames, ethanol mostly affects gas phase chemistry and consequently the formation of incipient particles.