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排序方式: 共有375条查询结果,搜索用时 15 毫秒
51.
Federico Morreale Donato Angelino Nicoletta Pellegrini 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(2):154-159
Gluten-free (GF) products are consumed both by individuals with celiac disease and by an increasing number of people with no specific medical needs. Although the technological quality of GF products has been recently improved, their nutritional quality is still scarcely addressed. Moreover, the few published studies report conflicting results, mostly because the information from product nutrition facts is the only considered factor. The aim of the present study was to develop a score-based method for the nutritional evaluation of 134 packaged Italian GF bakery products and to compare it with that of 162 matched gluten-containing (GC) food items. The score included the information from the nutrition facts and the presence/absence of some nutritionally relevant components in the ingredients list. Results indicated an overall low nutritional quality of the considered GF bakery products. Additionally, with the sole exception of GF bread substitutes, there was no difference in nutritional quality between GF and equivalent GC bakery products. Future research and development of GF bakery products may take advantage of this scoring method, as it may represent an easy approach to evaluate their nutritional quality. The present findings do not justify the consumption of packaged GF bakery products by people without any specific medical needs. 相似文献
52.
Federico Pallottino Marcello Biocca Pierfrancesco Nardi Simone Figorilli Paolo Menesatti Corrado Costa 《Precision Agriculture》2018,19(6):1011-1026
The relevance of precision agriculture produced a growth of the related literature over the years. However, a structured analysis of the published material is still missing. Thus, this study attempts to analyze the global scientific output of precision agriculture researches published during the period 2000–2016. By using a science mapping approach, mainly based on the application of network analysis tools, it was possible to investigate pivotal aspects of this research field such as publication trends, research topics and their geographical distribution. Using the Scopus database 17,756 scientific publications were retrieved from the chosen period. The number of publications increased after 2006, highlighting the vibrancy of the field. By authoring 35% of the publications, U.S.A. and China were the most active knowledge producer countries. Moreover, the generation of time resolved maps allowed us to identify agriculture engineering, computer science and agriculture studies as three main research areas characterizing precision agriculture panorama. The paper discusses the distribution of these topics at global level, among European countries and in Italy. Overall, this analysis represents the first holistic view of precision agriculture research providing valuable information for farmers, policy makers and researchers. 相似文献
53.
Durum wheat in temperate regions can lead to yields with higher technological quality and stability compared to Mediterranean areas. The aim of this study was to determine the effects of nitrogen (N fertilization on grain yield and quality, in different pedo-climatic conditions of temperate areas. Field experiments were conducted in two sites (sandy-loam and silty-clay-loam) in Northern-West Italy for three years: five different N rates, two different types of fertilizers (ammonium nitrate, nutritional activator, slow-release fertilizer) were compared considering yield, protein content and yellowberry. N fertilizer rate had a more consistent effect on protein than yield; the response was affected by soil texture and rainfall during the growing season. The use of different types of fertilizer seem to play a minor role. The management of N fertilization must consider mainly the effect on quality parameters of N rates and rainfall during the growing season and their interaction with soil texture. 相似文献
54.
Jorge Ruelas-Inzunza Federico Páez-Osuna Nydia Zamora-Arellano Felipe Amezcua-Martínez Humberto Bojórquez-Leyva 《Water, air, and soil pollution》2009,197(1-4):165-174
Variation of mercury (Hg) in sediments and biota from Coatzacoalcos estuary during the dry, rainy and windy seasons was estimated. In sediments, Hg concentrations ranged from 0.07 μg g?1 in site 13 (Ixhuatepec) located upstream, to 1.06 μg g?1 in site 3 (Coatzacoalcos river), located in the industrialized area. Highest enrichment factor (EF) and index of geoaccumulation (I geo) in surficial sediments were 53 and 5.1 respectively. From EF and I geo, it is considered that Coatzacoalcos estuary is from moderately contaminated to contaminated. In most fish species from Coatzacoalcos estuary, the sequence of Hg concentration was liver>muscle>gills. Average Hg concentrations in soft tissue of bivalves ranged from 0.09 μg g?1 in Corbicula fluminea to 0.18 μg g?1 in Polymesoda caroliniana. Biota-sediment accumulation factor (BSAF) ranged from 0.9 in P. caroliniana during the rainy season (site 4) to 3.8 in P. caroliniana from the same site during the windy season. 相似文献
55.
Coastal erosion is a widespread phenomenon on sandy coasts throughout the Mediterranean region; along the Thyrrenian coast of Tuscany (Italy), stone pine (Pinus pinea L.) stands originally planted for the protection of agricultural crops further inland are often damaged. In the present study, a pairwise comparison of stands at different distance from the sea at eroded and control sites highlighted the effects of coastal erosion alone on pine growth and function. Dendroecological analyses made it possible to determine the temporal dynamics of the phenomenon since 1930 and the interactions with climate, whilst additional structural (LAI, sapwood area) and functional (carbon isotope discrimination) measurements were used to discriminate between stress mechanisms. Salty winds, exacerbated by the removal of dunal vegetation, were found to be the most likely cause of the observed growth decline. The presence and, in more recent times, the reduction of surfactants in sea water played an important synergistic effect. The intrusion of salty water in the water table, on the contrary, played a marginal role at the site. Finally, stressed trees were more sensitive to the inter-annual variability in precipitation; at all sites, growth was stimulated by June, November and December precipitation in the current and two preceding years. 相似文献
56.
Federico Ferreres Graciliana Lopes Angel Gil-Izquierdo Paula B. Andrade Carla Sousa Teresa Mouga Patrícia Valent?o 《Marine drugs》2012,10(12):2766-2781
Purified phlorotannin extracts from four brown seaweeds (Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira tamariscifolia (Hudson) Papenfuss, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus), were characterized by HPLC-DAD-ESI-MSn. Fucophloroethol, fucodiphloroethol, fucotriphloroethol, 7-phloroeckol, phlorofucofuroeckol and bieckol/dieckol were identified. The antioxidant activity and the hyaluronidase (HAase) inhibitory capacity exhibited by the extracts were also assessed. A correlation between the extracts activity and their chemical composition was established. F. spiralis, the species presenting higher molecular weight phlorotannins, generally displayed the strongest lipid peroxidation inhibitory activity (IC50 = 2.32 mg/mL dry weight) and the strongest HAase inhibitory capacity (IC50 = 0.73 mg/mL dry weight). As for superoxide radical scavenging, C. nodicaulis was the most efficient species (IC50 = 0.93 mg/mL dry weight), followed by F. spiralis (IC50 = 1.30 mg/mL dry weight). These results show that purified phlorotannin extracts have potent capabilities for preventing and slowing down the skin aging process, which is mainly associated with free radical damage and with the reduction of hyaluronic acid concentration, characteristic of the process. 相似文献
57.
58.
Annual survival probabilities of juvenile loggerhead sea turtles indicate high anthropogenic impact on Mediterranean populations
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Paolo Casale Daniela Freggi Giovanni Furii Carola Vallini Pasquale Salvemini Michele Deflorio Giovanni Totaro Stefano Raimondi Caterina Fortuna Brendan J. Godley 《水产资源保护:海洋与淡水生态系统》2015,25(5):690-700
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59.
Gianmarco?Mugnai Federico?RossiEmail authorView authors OrcID profile Vincent?John?Martin?Noah?Linus?Felde Claudia?Colesie Burkhard?Büdel Stephan?Peth Aaron?Kaplan Roberto?De?Philippis 《Biology and Fertility of Soils》2018,54(1):27-40
Soil inoculation with cyanobacteria (cyanobacterization) is a biotechnological method widely studied to improve soil quality and productivity. During their growth on soil, cyanobacteria excrete exopolysaccharides (EPSs) which glue trichomes to soil particles, in a three-dimensional extracellular polymeric matrix. EPS productivity is an important screening parameter to select proficient inoculants and is affected by growth conditions and abiotic stresses. In this study, we evaluated the capability of the cyanobacterium Schizothrix cf. delicatissima AMPL0116 to form biocrusts when inoculated in sand microcosms under stressing conditions, and the characteristics of the synthesized polymeric matrix. In parallel, we evaluated the characteristics of exopolysaccharidic exudates of the strain when grown in liquid culture, under optimal growth setting. Our results pointed out at significant differences of the exopolymers produced in the two conditions in terms of monosaccharidic composition and molecular weight distribution, and proved the capability of S. cf. delicatissima AMPL0116 to form stable bioaggregates on sandy soils. 相似文献
60.
Andreas Rais Enrico Ursella Enrico Vicario Federico Giudiceandrea 《Annals of Forest Science》2017,74(2):28