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The elastic scattering in the reaction 7 Li+ 208 Pb was investigated in the bombarding energy range from 25 to 39 MeV. The real and imaginary parts of the optical potential were analyzed by using a phenomenological potential. A dispersion relation analysis is presented in order to investigate the threshold anomaly effect. It is concluded that 7 Li has an intermediate behavior between the tightly bound nuclei such as 16 O and the loosely bound nuclei such as 6 Li where the lack of the threshold anomaly is unambiguously observed. Reaction cross sections are also extracted from the elastic scattering data and its comparison with the ones of other systems has been performed to draw hints on the effect of the breakup channel. [ABSTRACT FROM AUTHOR]

A 4 π light charged particle spectrometer, called 8 π LP, is in operation at the Laboratori Nazionali di Legnaro, Italy, for studying reaction mechanisms in low-energy heavy-ion reactions. Besides about 300 telescopes to detect light charged particles, the spectrometer is also equipped with an anular PPAC system to detect evaporation residues and a two-arm time-of-flight spectrometer to detect fission fragments. The spectrometer has been used in several fission dynamics studies using as a probe light charged particles in the fission and evaporation residues (ER) channels. This paper proposes a journey within some open questions about the fission dynamics and a review of the main results concerning nuclear dissipation and fission time-scale obtained from several of these studies. In particular, the advantages of using systems of intermediate fissility will be discussed. [ABSTRACT FROM AUTHOR]

In the present paper we study the stability analysis of double-diffusive convection in a horizontal layer of an elastico-viscous nanofluid in a porous medium. The Rivlin-Ericksen fluid model is employed to describe the rheological behavior of the nanofluid. The dispersion relation describing the effect of various parameters is obtained by applying normal modes method and by using linear stability analysis. In this model we assume that the nanoparticle concentration flux is zero on the boundaries and we can give the values of temperature and concentration at the boundaries. The assumed boundary conditions neutralize the possibility of oscillatory convection and only stationary convection occurs. For stationary convection; it is observed that the Rivlin-Ericksen elastico-viscous nanofluid fluid behaves like an ordinary Newtonian nanofluid. The solutal-Rayleigh Number, thermo-nanofluid Lewis number, thermo-solutal Lewis number, Soret parameter and Dufour parameter have stabilizing effect on the stationary convection. A very good agreement is found between the present paper and earlier published results. [ABSTRACT FROM AUTHOR]

Analyses of volatile organic compounds (VOCs) produced by three Monilinia species (M. laxa, M. fructigena and M. fructicola) grown on potato dextrose agar (PDA) were done by head space solid phase micro extraction combined with gas chromatography/mass spectrometry (HS-SPME-GS/MS). A total of 14 compounds of different chemical structure were identified, the most frequent of which were ethanol, dodecane and alpha-Muurolene. Specific VOCs were identified, which allowed the discrimination of the three Monilinia species. If coupled with the use of the electronic nose and upon validation under commercial conditions, the results of this study may have potential applications in postharvest for detecting and identifying diseases of stone and pome fruits, in relatively early stages of their development. [ABSTRACT FROM AUTHOR]

Conversion of broad-spectrum organic waste into carbonaceous biochar has gained enormous interest in past few years. The present study aims to characterize feedstock (FS), i.e. bagasse (Bg), bamboo (Bm) and biochar (BC), i.e. baggase biochar (BBg), bamboo biochar (BBm) and tyre biochar (Ty). Significant changes in elemental composition, atomic ratio, proximate analyses, mineral content and heavy metal content were observed which was well supported by Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analysis. Impregnation with ferric hydroxide was done, and resultant modified biochars (MBC), i.e. iron-impregnated baggase biochar (FeBBg), iron-impregnated bamboo biochar (FeBBm) and iron-impregnated tyre biochar (FeTy), along feedstock and biochar were used for PO, Pb, Hg and Cu adsorption. In general, BBg, FeBBg, BBm, FeBBm, Ty and FeTy were found to adsorb PO, Pb, Hg and Cu better than Bg and Bm, except in few cases. Results from adsorption experiments were fitted into Langmuir, Freundlich and Temkin models of isotherms and pseudo-first-order, pseudo-second-order and Elovich models of kinetics. Result of batch study adsorption revealed that maximum adsorption of PO, Pb, Hg and Cu was done by FeBBg (adsorption mechanism explained by Freundlich model), FeTy (Temkin model), Ty (Langmuir model) and BBm (Langmuir model) respectively. According to R values, pseudo-first-order reaction was well suited to PO, Pb, Hg and Cu adsorption. The optimum pH for maximum adsorption was observed to be 7.4 for PO, 5 for Cu and 6 for Pb and Hg respectively [ABSTRACT FROM AUTHOR]

In this paper, oscillatory convection in a horizontal layer of nanofluid in porous medium is studied. For porous medium, Darcy model is applied. A linear stability theory and normal mode analysis method is used to find the solution confined between two free boundaries. The onset criterion for oscillatory convection is derived analytically and graphically. Regimes of oscillatory and non-oscillatory convection for various parameters are derived. The effects of Lewis number, concentration Rayleigh number, Prandtl-Darcy number (Vadasz Number) and modified diffusivity ratio on the oscillatory convection are investigated graphically. We examine the validity of 'PES' and concluded that 'PES' is not valid for the problem. [ABSTRACT FROM AUTHOR]

Starch was separated from tubers of four potato ( Solanum tuberosum L.) cultivars, viz. ‘Kufri Jyoti’, ‘Kufri Sindhuri’, ‘Kufri Chipsona-1’ and ‘Kufri Chipsona-2’ before and after 90 days of storage at 4, 8, 12 and 16°C and, morphological, physico-chemical and pasting properties were studied. Scanning electron microscopy showed oval and irregular shaped starch granules with average diameter of 15 μm, and the granule diameter increased after storage. Peak viscosity was lower after storage at 8°C and higher at 16°C. Hot paste viscosity decreased while breakdown viscosity and set back viscosity increased after storage, and there was no significant change in cold paste viscosity. A significant decrease in pasting time and increase in pasting temperature was observed after storage. Phosphorus content showed significant positive correlation with peak viscosity (r = 0.452, p <0.05) and breakdown viscosity (r = 0.685, p <0.01), and a negative correlation with amylose content (r = −0.674, p <0.01). ‘Kufri Sindhuri’ starch showed significantly (p <0.05) higher peak, hot paste, breakdown and cold paste viscosity. The X-ray diffraction pattern of starch showed a distinctive maximum peak at around 17°, 2 ϑ and it was not affected by the cultivar or storage temperature. [ABSTRACT FROM AUTHOR]

Light charged-particle multiplicities in the evaporation residue (ER) and fission (FF) channels from the reaction 200MeV 32S + 100Mo as well as ER and FF channel cross-sections have been measured and compared to the predictions of the statistical model (SM) to estimate the fission time scale. The statistical model fails in reproducing the whole set of data and no convincing estimate is possible. In particular, while pre-scission multiplicities can be reproduced, the model strongly overestimates proton and alpha particle multiplicities in the ER channel, irrespective of the SM input parameters and prescriptions used for the level density and the transmission coefficients. Same calculations performed on data from literature in the A $ \approx$ 150 and excitation energy Ex $ \approx$ 100-200 MeV region, for the ER channel, provide similar conclusions. These findings repropose the problem of the reliability of the SM in describing the compound-nucleus decay and have a relevant impact on the extraction of the fission delay time through the use of the SM. [ABSTRACT FROM AUTHOR]

The topography of hilly landscapes modifies crop environment changing the fluxes of water and energy, increasing risk in these vulnerable agriculture systems, which could become more accentuated under climate change (drought, increased variability of rainfall). In order to quantify how wheat production in hilly terrain will be affected by future climate, a newly developed and calibrated micro-meteorological model for hilly terrain was linked to a crop growth simulation model to analyse impact scenarios for different European regions. Distributions of yield and growing length of rainfed winter wheat and durum wheat were generated as probabilistic indices from baseline and low (B2) and high (A2) emission climate scenarios provided from the Hadley Centre Regional Climate Model (HadRM3). We used site-specific terrain parameters for two sample catchments in Europe, ranging from humid temperate (southeast UK) to semi-arid Mediterranean (southern Italy). Results for baseline scenario show that UK winter wheat is mainly affected by annual differences in precipitation and yield distributions do not change with terrain, whilst in the southern Mediterranean climate yield variability is significantly related to a slope × elevation index. For future climate, our simulations confirm earlier predictions of yield increase in the UK, even under the high emission scenario. In the southern Mediterranean, yield reduction is significantly related to slope × elevation index increasing crop failure in drier elevated spots but not in wet years under baseline weather. In scenarios for the future, the likelihood of crop failure rises sharply to more than 60%, and even in wet years, yields are likely to decrease in elevated spots. [ABSTRACT FROM AUTHOR]

The aims of this paper were to study the genetic diversity within and among 6 Tuber taxa, the phylogenetic relationships and the spatial distribution of truffles from the Basilicata region (southern Italy). Molecular analyses, using the internal transcribed spacer region, microsatellites, minisatellites and random amplified polymorphic loci revealed the highest expected intra-specific heterozygosity (He=0.30) in T. aestivum, followed by that of T. mesentericum (He=0.22). T. borchii (He=0.17), T. magnatum (He=0.16), T. aestivum fo. uncinatum (He=0.12) and T. brumale fo. moschatum (He=0.09) showed a lower average heterozygosity. The whole set of markers were demonstrated to be useful in clearly differentiating Tuber taxa, separating them in two distinct groups and in five sub-clusters, each corresponding to one single taxon. The first cluster (T. borchii, T. magnatum and T. brumale fo. moschatum) was more differentiated than the second one (T. aestivum, T. aestivum fo. uncinatum and T. mesentericum). T. brumale fo. moschatum was the most differentiated Tuber taxon. It was more related to the white truffles (the closely related T. borchii and T. magnatum) than to the remaining related black truffles T. aestivum and T. mesentericum. The amount of Tuber species richness was higher over the western side of Basilicata, in cold Lauretum and in Castanetum phytoclimatic Pavari's zones. A spatial genetic structure was detected for T. aestivum, as shown by the significant correlation between geographic and genetic distances (rs=0.32; P<0.0001). Integration of molecular and geographic diversity patterns can allow the selection of sites for Tuber and Tuberrelated biodiversity conservation. [ABSTRACT FROM AUTHOR]

The excitation energy above the breakup threshold of the α + d/6Li system, after the interaction of 6Li nuclei with a 208Pb target, was deduced from the invariant mass of the α + d system. Data were collected with a large-solid-angle detector set-up at four beam energies around the Coulomb barrier. The excitation of the 6Li nucleus above the breakup threshold (1.47 MeV) has a quite similar behavior at each measured beam energy and angle; it is peaked at ∼ 1 MeV above the threshold and shows an exponential decay on the high energy side, which is a clear signature of a direct breakup process. The experimental excitation energies are reproduced both in shape and absolute value by 1) fully quantum-mechanical Coupled-Channel calculations with coupling to discretized-continuum 6Li excitations, 2) semi-classical Coupled-Channel approach, where the relative motion is treated along a classical trajectory. [ABSTRACT FROM AUTHOR]

A 4&pie; light charged particle spectrometer, named 8&pie;LP, is in operation at the Laboratori Nazionali di Legnaro (Italy) for the study of the reaction mechanisms produced in low-energy heavy-ion reactions. The spectrometer has recently been used in a study of fission dynamics that involves the detection of light charged particles in the fission and evaporation residue channel in a system of intermediate fissility, as well as in a study of multinucleon transfer to heavy target. Data on the system 240 MeV [SUP32]S + [SUP100]Mo are presented. Dynamical effects extracted as a consequence of the comparison of the data to the statistical model calculations are discussed. [ABSTRACT FROM AUTHOR]

Light particles in coincidence with evaporation residues and heavy fragments have been measured by a 4π charged-particle detector at the INFN Laboratori Nazionali di Legnaro (Padua) for the 240 MeV32S +100Mo reaction leading to the132Ce composite system at 152 MeV of excitation energy. Energy spectra of the alpha-particles in coincidence with fission fragments were extracted for many correlation angles both in plane and out of plane. A prominent out-of-plane emission was observed, consistent with the pattern for the near-scission emission. From the fit to the spectra, the pre-scission alpha-particle multiplicity of 0.040±0.006 was obtained. This value is reproduced by the code PACE2 without the inclusion of a delay time for fission. The presence of fast fission, which could be responsible for this result, is discussed. [ABSTRACT FROM AUTHOR]

Large cross-section reaction channels were measured in the systems 6Li( 7Li) + 208Pb with high statistical accuracy at 5(3) energies around the Coulomb barrier from 29 to 39 MeV. These channels were assigned (mainly) to the breakup of 6Li, very loosely bound, into α + d and to the breakup of 5Li, produced by n-transfer to the target, into α + p and to similar processes with 7Li beam. The cross-sections with 6Li, Sα = 1.475 MeV, are systematically larger than the 7Li ones. This reflects, most likely, the higher binding energy of 7Li, Sα = 2.468 MeV. Theoretical predictions for the 6Li + 208Pb system which include for 6Li breakup to continuum states within a continuum discretized coupled-channels approach (CDCC) and resonant breakup plus n-transfer with DWBA reproduce the angular distribution shapes but still underestimate the cross-sections by a factor ∼ 3. [ABSTRACT FROM AUTHOR]

Shows that the endogenous cannabinoid anandamide exerts dual effects on bronchial responsiveness in rodents. Finding that it strongly inhibits bronchospasm and cough evoked by the chemical irritant capsaicin and causes bronchospasm when the constricting tone exerted by the vagus nerve is removed; Significance in relation to the contrasting bronchial actions of cannabis-like drugs in humans; Framework provided by the study for the development of cannabinoid-based agents for the treatment of respiratory pathologies.

The study of the α-particle energy distributions associated with ND and SD states in 151,152Dy has been carried out. The Dy isotopes were produced in the reaction 37Cl +123Sb at 191 MeV via the (α5n) and (α4n) channels, respectively. In 151Dy the α-particle energy distributions associated to ND and SD are very different from each other, both at the low and high energy sides inducing a difference of 3 MeV in the α-particle mean energy. In 152Dy the situation is different; the α-particle spectral shapes are similar and a difference in the α-particle mean energy of only 0.7 MeV is deduced. A description in terms of energy localization of entry states is given. [ABSTRACT FROM AUTHOR]

The measurement of water consumption in the field is normally restricted to research purposes, although the development of practical field criteria for timing water application is required to improve crop productivity. To develop such criteria irrigation experiments on Soybean were conducted from flowering to grain filling at four locations which differed in their soil properties and the convective contribution of their climates to potential evapotranspiration. The energy balance, predawn leaf water potential (PLWP), soil moisture depletion, and a crop water stress index (CWSI) based on foliage temperature were measured. The range of soil, atmospheric, phenological and irrigation conditions, produced a common, linear relation between relative evapotranspiration (rET) and the logarithm of -PLWP. Correlation with the temperature based CWSI was weak. A similar relation with PLWP for other C plants was also derived from data in the literature. This relation could be helpful for irrigation scheduling once the critical values of rET for crop productivity are known. [ABSTRACT FROM AUTHOR]

We describe a simple dynamical model for the production of prompt nucleons at the very beginning of a heavy ion collision. Approximations often used in previous calculations (neglect of Pauli blocking, of window velocity and of its extension) have been checked. We apply the model to the calculation of prompt emitted neutrons in incomplete fusion reactions observed on theNe+Ho system at 220, 402 and 700 MeV. Results of the model are extensively discussed. [ABSTRACT FROM AUTHOR]

The α-particle emission from the 28Si+170Er fusion-evaporation reaction at 165 and 185 MeV has been measured and compared with published data relative to the pre-scission emission in the same reaction. The spectra in the two channels exhibit nearly the same shape in the low energy region, whereas in the high energy region the spectrum for the fusion-evaporation case features a larger apparent temperature. The interpretation of the difference in shape between the two decay channels is based on statistical model calculations which account for the effects due to the different length of the decay chain. Statistical model calculations with standard parameters describe well the gross features of the alpha particle spectra in the fusion-evaporation channel and the proton spectra in the pre-scission channel. On the contrary, the model predictions seem to overestimate by ≃2 MeV the emission barrier for the alpha particles in the pre-fission channel. This effect is ascribed to the larger elongation of the nucleus during the fission process. An average axis ratio b/a∼ 2 for the emitter is suggested. [ABSTRACT FROM AUTHOR]

A 4π detection system sensitive to light charged particles is being developed at the Laboratori Nazionali di Legnaro (LNL) for the study of the reaction mechanisms produced in heavy-ion collisions at energies up to 20 A MeV. The 8πLP apparatus is a telescope assembly characterized by a large solid angle (90% of 4π) and high granularity (262 modules). Particle identification at low energy is obtained by combining π E-E, TOF and PSD techniques. Thresholds for particle identification range from 1 MeV for protons and 3 MeV for alpha-particles to about 2-3 A MeV for C ions. The system is fully operational for experiments. [ABSTRACT FROM AUTHOR]

We have measured the high-energy γ-ray spectra from the fusion reactions 130 MeVO +Mo and 240 MeVTi +Ni, populating theSn andSn compound nuclei at the excitation energy of 110 MeV. The comparison of the spectra shows a ~36% enhancement of the α-ray yield in the Giant Dipole Resonance region ( E > 8 MeV) when the O-induced reaction is considered. This enhancement is interpreted as due to entrance channel effects related to the N/ Z asymmetry between the target and the projectile. [ABSTRACT FROM AUTHOR]

The coupling of efficient particle and γ detection arrays is a powerful tool to study the deexcitation of both compound and residual nuclei in fusion evaporation reactions.We show first results obtained coupling the DIAMANT (4π light charged particle array) and EUROGAM (4π γ array) detectors demonstrating the improvement in the resolving power by this combination. For γ rays of ≃800keV improvements in the Doppler correction up to 50% have been reached for the 2α exit channel following the fusion of 32S+58Ni at 120 MeV bombarding energy (β ≃ 3%). [ABSTRACT FROM AUTHOR]

Yellowing or bacteriosis is the most severe disease of Pleurotus eryngii (DC. : Fr.) Quél., the mushroom commonly called "cardoncello" that is particularly appreciated in Italy and in some foreign countries (Germany, Canada, etc.). Pseudomonas 'reactans' species complex, and P. tolaasii Paine, saprophytic bacteria inhabiting the mushroom hyphosphere, are reported, though with different importance, as the causal agents of the disease that sometimes causes huge losses to "cardoncello" cultivations. Control of the bacteriosis using white vinegar (6‰ acidity, pH 3.2), ozone (12-15 ppm) or 95.2 mM acetic acid was attempted. Two different cultivation cycles were carried out with P. eryngii strains "51" and "65" provided by Micotec (Gravina di Puglia, Italy) after incubation in standard substrate contained in thermoresistant polypropylene bags. The casing soil of each bag was inoculated with 10 ml of a suspension containing 1.7x108 CFU ml-1 of PR51 strain of P. 'reactans', previously isolated from "cardoncello" basidiomata affected by yellowing. Antibacterial treatments were carried out 13 times during the 43 days of each productive cycle. Substrate bags used as control were sprayed with tap water. For each bag, appearance and development of disease symptoms, ba-idioma shape and size, marketable mushroom yield and number of total bacteria, fluorescent Pseudomonads and total fungi presents in casing soil were recorded. Several basidiomata produced by control bags showed severe yellowing symptoms. Vinegar, ozone and acetic acid significantly prevented bacteriosis appearance and development and reduced the number of total bacteria, fluorescent Pseudomonads and total fungi present in casing soil of compost bags. [ABSTRACT FROM AUTHOR]

Transpiration of an adult corn crop was measured with the sap flow method using the stem heat balance technique. The 1 ha-field was located in the Parisian region and the measurements were taken over two consecutive years (1993 and 1994). The experiments were carried out during the active growing season, leaf area index being \approx4.0. In order to individuate the 'mean plant' a preliminary analysis was carried out to determine the frequency distribution of plant stem diameters as measured on 34 randomly chosen samples. According to this analysis, the mean corn plant diameter was around 20 mm for both years. As a consequence, the sap flow gauges were installed on plants having this diameter. The sap flow transpiration data was compared with the actual evapotranspiration measured by the Bowen ratio method on the same experimental field at the hourly and daily scales. The comparison between sap flow transpiration and actual evapotranspiration showed that the values are more widely spread at the hourly scale than at the daily scale due to the kinetics of plant water content during the day. Sap flow transpiration was 88-90% of actual evapotranspiration: this lack of about 10-12% is of the same order as soil water evaporation. In conclusion, the sap flow transpiration method could be considered a valuable method to use for measuring transpiration of certain crop plants in the field, especially for small plots. This method is substantially improved if sap flow measurement is carried out on plants screened by the analysis of plant diameter distribution in the field. [ABSTRACT FROM AUTHOR]

This paper presents a study of the sensibility of the Penman-Monteith evapotranspiration model to climatic (available energy and vapour pressure deficit) and parametric (aerodynamic and canopy resistances, ra and rc respectively) factors in a semi-arid climate, for crops in contrasting water status (well irrigated and under water stress) and of different heights. Three experiments were carried out in southern Italy on reference grass (\approx 0.1 m), grainsorghum (\approx 1 m) and sweet sorghum (\approx 3 m). For this analysis the sensitivity coefficients, taken as hourly means, were evaluated during the growth season when the crops completely covered the soil. The relative errors on evapotranspiration were also evaluated forra and rc. The results showed that, for reference grass, available energy and aerodynamic resistance play a major role. For crops under water stress the most important term to evaluateis canopy resistance. For a tall crop, as sweet sorghum, the role ofthe vapour pressure deficit is fundamental, both when the crop is ingood water status and under water stress. [ABSTRACT FROM AUTHOR]

In this paper a model for estimating actual evapotranspiration is developed and tested for field crops (grain sorghum and sunflower) maintained under water stress conditions. The model is based on the Penman-Monteith formulation of ET in which canopy resistance (r{sub}c{end}) is modeled with respect to the crop water status and local climatological conditions. The model was previously tested on reference grass; in this last case no reference was made to soil water conditions and r{sub}c{end} was modeled only as a function of climatological parameters. Here r{sub}c{end} is expressed as a function of available energy, vapour pressure deficit, aerodynamic resistance and crop water status by means of predawn leaf water potential. Results, obtained withvarious crop water stress intensities, show that, on a daily scale, calculated ET is 98% and 95% of the measured ET for sorghum and sunflower respectively. The correlation between daily calculated and measured ET is very high (r{sup}2{end} = 0.95 for sorghum and r{sup}2{end}= 0.98 for sunflower). On an hourly scale, the model works very wellwhen the crops were not stressed and during the senescence stage. Incase of weak and strong stress the model has to be used with some precautions. [ABSTRACT FROM AUTHOR]