排序方式： 共有16条查询结果，搜索用时 15 毫秒
1.
Gianluigi Mazza Alessandro Elio Agnelli Maria Costanza Andrenelli Alessandra Lagomarsino 《Archives of Agronomy and Soil Science》2018,64(5):654-667
GHGs production and emission may vary depending on soil physical properties, water management and fertilization. Two paddy soils characterized by different texture were incubated to evaluate the impact of flooding (permanent or intermittent) and N addition on potential N2O, CH4 and CO2 production and release into atmosphere and soil solution. Relationships with volumetric water content (VWC) and water filled pore space (WFPS) were evaluated. Overall, the finer clayey soil (CL) produced 58% more CH4 than the coarser sandy soil (SA) and showed an earlier sink to source transition; the difference was lower with N addition. Permanent flooding favoured the amount of dissolved CH4. SA produced more N2O emissions than CL under permanent flooding (31.0 vs. 3.7%); an opposite pattern was observed for dissolved N2O (16.4 vs. 52.7%). Fertilization increased N2O emissions under dry conditions in CL and under flooding in SA.
Our findings showed that i) VWC had a larger influence on N2O and CH4 emissions than WFPS, ii) soil type influenced the gas release into atmosphere or soil solution and the timing of sink to source transition in CH4 emissions. Further investigation on timing of fertilization and drainage are needed to improve climate change mitigation strategies. 相似文献
2.
Gianluigi Mazza Emilio Amorini Andrea Cutini Maria Chiara Manetti 《Annals of Forest Science》2011,68(8):1323-1332
• Context
This research was conducted in a 62-year-old stone pine (Pinus pinea L.) forest within the National Natural Reserve of the Roman Coast, Italy. Net under-canopy precipitation was measured between September 2004 and December 2008 in a unthinned and a thinned area of about 1 ha each. 相似文献3.
It is usually assumed that enhanced spiking activity in the form of persistent reverberation for several seconds is the neural correlate of working memory. Here, we propose that working memory is sustained by calcium-mediated synaptic facilitation in the recurrent connections of neocortical networks. In this account, the presynaptic residual calcium is used as a buffer that is loaded, refreshed, and read out by spiking activity. Because of the long time constants of calcium kinetics, the refresh rate can be low, resulting in a mechanism that is metabolically efficient and robust. The duration and stability of working memory can be regulated by modulating the spontaneous activity in the network. 相似文献
4.
Paolo Bruno Maurizio Caselli Gianluigi de Gennaro Lucia Scolletta Livia Trizio Maria Tutino 《Water, air, and soil pollution》2008,193(1-4):37-50
Volatile organic compounds (VOC) have been monitored in 12 sites of Canosa di Puglia, a city located in the Southern of Italy, in order to identify the main VOC source—vehicular traffic or industrial—and to evaluate the critical situations in the city. Monitoring, carried out by using Radiello® diffusive samplers, has been planned taking into account the traffic density and the architecture of the city. From the study of the data it has been emerged that, among all considered VOC, benzene, toluene, ethylbenzene and xylenes (BTEX) are the pollutants at higher concentration. However no critical situation has appared from the present monitoring. Maps of daily benzene and toluene concentrations have shown that the most significant pollution phenomena happens in the center of the urban area which is in a valley with narrow roads and high buildings that do not allow an efficient dispersion of pollutants. The study of the diagnostic ratios between the toluene and benzene concentrations in the several areas (average T/B?=?3.4) and the high Pearson’s coefficient among the pollutants, and in particular between benzene and toluene concentrations (r?=?0.9505), have suggested that in urban area these pollutants are emitted from the same source: the vehicular traffic. 相似文献
5.
Zadra C Cardinali G Corte L Fatichenti F Marucchini C 《Journal of agricultural and food chemistry》2006,54(13):4734-4739
Iprodione is a contact fungicide used to control several pathogens such as Botrytis cinerea, Monilia, and Sclerotinia. This paper reports the ability of an iprodione-resistant strain of Zygosaccharomyces rouxii to degrade iprodione at a concentration of 1 mg L(-1). The yeast Z. rouxii was chosen also for its ability to grow at high osmolarity. Also of note is that in bioremediation situations and in the food industry such resistance could be important. The kinetic and metabolic behaviors of the fungicide in the media are described. The results show a new transformation pathway of iprodione by the yeast leading to the formation of N-(3,5-dichlorophenyl)-2,4-dioxoimidazoline, 3-isopropylhydantoin, and 3,5-dichloroaniline. These compounds were identified by 1H NMR, 13C NMR, and GC-MS analyses. This study provides a basis to employ yeast strains in biodegradation studies in relation to their ability in the disappearance and degradation of xenobiotics into simpler molecules. 相似文献
6.
7.
Carmen Festa Claudio D’Amore Barbara Renga Gianluigi Lauro Simona De Marino Maria Valeria D’Auria Giuseppe Bifulco Angela Zampella Stefano Fiorucci 《Marine drugs》2013,11(7):2314-2327
Further purification of the apolar extracts of the sponge Plakinastrella mamillaris, afforded a new oxygenated polyketide named gracilioether K, together with the previously isolated gracilioethers E–G and gracilioethers I and J. The structure of the new compound has been elucidated by extensive NMR (1H and 13C, COSY, HSQC, HMBC, and ROESY) and ESI-MS analysis. With the exception of gracilioether F, all compounds are endowed with potent pregnane-X-receptor (PXR) agonistic activity and therefore represent a new chemotype of potential anti-inflammatory leads. Docking calculations suggested theoretical binding modes of the identified compounds, compatible with an agonistic activity on hPXR, and clarified the molecular basis of their biological activities. 相似文献
8.
Pietro Volta Paolo Tremolada Maria Chiara Neri Gianluigi Giussani Silvana Galassi 《Water, air, and soil pollution》2009,197(1-4):193-209
Fish and piscivorous bird eggs collected in 2003 from Lake Maggiore (Italy), were analysed for PCB and DDT contamination. Lake Maggiore has been severely polluted by DDT through production of the pesticide within its catchment. Although agricultural application of DDT was banned in Italy in the 1978, industrial production continued until 1996, with enough contamination of water and soil for serious bioaccumulation in the lake biota. PCB and DDT concentrations in a whitefish (Coregonus macrophthalmus Nusslin 1882) were seen to be dependent on season and fish age, but not on sex. The average increase of the lipid-normalised concentration of DDTs and PCBs was two-fold across season and also across age, resulting in an overall increase of four fold. The seasonal variation was related to the eco-physiological cycle of the fish and to the contamination dynamic of the lake, while the effect of the fish age was explained on the base of biomagnification-related mechanisms. A fugacity model was applied to predict the age-dependent bioaccumulation potential of PCBs, whose concentrations were rather stable in recent years in the lake. Predicted values for compounds with negligible biotransformation were in good agreement with experimental data (calculated vs. experimental mean difference of 14%), and a relationship between the increase of experimental age-dependent concentration and K ow was observed. The good correspondence between the predicted and the measured values for most PCB congeners confirmed the general inability of fishes to biotransform these compounds. On the contrary, the importance of biotransformation processes was recognised in birds; eggs of a fish eating bird (Podiceps cristatus) from the same area selectively bioaccumulated p,p′-DDE. For PCBs, congener 149 appears to be completely metabolized by the bird species, and congeners 95, 101, 132, 151 and 174 were reduced as well. The role of the meta–para free position on at least one phenyl ring of PCB congeners in biotransformation processes was confirmed. 相似文献
9.
Di Pasqua R Hoskins N Betts G Mauriello G 《Journal of agricultural and food chemistry》2006,54(7):2745-2749
Major active compounds from essential oils are well-known to possess antimicrobial activity against both pathogen and spoilage microorganisms. The aim of this work was to determine the alteration of the membrane fatty acid profile as an adaptive mechanism of the cells in the presence of a sublethal concentration of antimicrobial compound in response to a stress condition. Methanolic solutions of thymol, carvacrol, limonene, cinnamaldehyde, and eugenol were added into growth media of Escherichia coli O157:H7, Salmonella enterica serovar typhimurium, Pseudomonas fluorescens, Brochothrix thermosphacta, and Staphylococcus aureus strains. Fatty acid extraction and gas chromatographic analysis were performed to assess changes in membrane fatty acid composition. Substantial changes were observed on the long chain unsaturated fatty acids when the E. coli and Salmonella strains grew in the presence of limonene and cinnamaldehyde and carvacrol and eugenol, respectively. All compounds influenced the fatty acid profile of B. thermosphacta, while Pseudomonas and S. aureus strains did not show substantial changes in their fatty acid compositions. 相似文献
10.
Federico Casale Gianluigi Nieddu Elisa Burdino Davide A. L. Vignati Carlo Ferretti Giancarlo Ugazio 《Water, air, and soil pollution》2009,196(1-4):141-149
Several studies have shown the association between ambient particulate matter (PM) and adverse health effects, thus highlighting the need to limit the anthropogenic sources of PM, especially motor vehicle emissions. PM exposure is commonly monitored as mass concentration of PM10 or PM2.5, although increasing toxicity with decreasing aerodynamic diameter has been reported. In the present study an analysis was performed of the concentration and size distribution of airborne PM fractions collected at street level in the city center of Turin, Italy, to verify the usefulness of “ecological” days with traffic limitations. PM levels were determined daily at five different outdoor sites, from Thursday to Tuesday for 7 weeks (five with “ecological” Sunday, two with normal traffic density). Air sampling was performed using a six-channel laser particle counter to determine the number of particles (n°/l) in six size ranges between 0.3 and 10 μm. Climatic conditions and indoor PM levels were also monitored. The PM size distribution was constant for all the samples tested, with the 90% of the particles smaller than 0.5 μm, suggesting that measurements for count are needed in addition to the traditional ones based on the mass. The total number of particles was highly variable comparing days or weeks of monitoring, but much less among the sites of air sampling. The restriction of motor vehicle circulation has not determined any significant effect on PM levels and, in the winter period, PM0.5 peak concentrations were measured also on the ecological days. 相似文献