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201.
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203.
Noelle Giacomini Lemos Alessandro de Lucca e Braccini Ricardo Vilela Abdelnoor Maria Cristina Neves de Oliveira Kazuhiro Suenaga Naoki Yamanaka 《Euphytica》2011,182(1):53-64
Asian rust, caused by the fungus Phakopsora pachyrhizi, is the most severe disease currently threatening soybean crops in Brazil. The development of resistant cultivars is a top
priority. Genetic characterization of resistance genes is important for estimating the improvement when these genes are introduced
into soybean plants and for planning breeding strategies against this disease. Here, we infected an F2 population of 140 plants derived from a cross between ‘An-76’, a line carrying two resistance genes (Rpp2 and Rpp4), and ‘Kinoshita’, a cultivar carrying Rpp5, with a Brazilian rust population. We scored six characters of rust resistance (lesion color [LC], frequency of lesions having
uredinia [%LU], number of uredinia per lesion [NoU], frequency of open uredinia [%OU], sporulation level [SL], and incubation
period [IP]) to identify the genetic contributions of the three genes to these characters. Furthermore, we selected genotypes
carrying these three loci in homozygosis by marker-assisted selection and evaluated their genetic effect in comparison with
their ancestors, An-76, PI230970, PI459025, Kinoshita and BRS184. All three genes contributed to the phenotypes of these characters
in F2 population and when pyramided, they significantly contributed to increase the resistance in comparison to their ancestors.
Rpp2, previously reported as being defeated by the same rust population, showed a large contribution to resistance, and its resistance
allele seemed to be recessive. Rpp5 had the largest contribution among the three genes, especially to SL and NoU. Only Rpp5 showed a significant contribution to LC. No QTLs for IP were detected in the regions of the three genes. We consider that
these genes could contribute differently to resistance to soybean rust, and that genetic background plays an important role
in Rpp2 activity. All three loci together worked additively to increase resistance when they were pyramided in a single genotype
indicating that the pyramiding strategy is one good breeding strategy to increase soybean rust resistance. 相似文献
204.
Particle Number Size Distribution and Weight Concentration of Background Urban Aerosol in a Po Valley Site 总被引:2,自引:0,他引:2
Measurements of particle size distributions and PM2.5 from an urban background site in the Central Po Valley are analysed; the site is one of the medium–small-size cities in the central valley, without the direct influence of the metropolitan and industrial area of Milan and of the Adriatic Sea. The data comprise number concentration of particle with diameters ranging between 10 and 700 nm, PM2.5 and main meteorological variables from February to August 2008. Daily cycles of the observed pollutants are analysed, along with auto-correlation function for particle number concentration and principal component analysis (PCA) of all the available variables; finally, the diurnal pattern of PM2.5 low-, medium- and high-pollution events has been investigated. Total particle number concentration showed a daily pattern both in winter and summer, although different between weekdays and Sundays and with wider variations during the cold season. A daily cycle is present for the geometric mean diameter of nucleation mode particles in winter and of nucleation and Aitken mode particles in summer. PM2.5 showed a slight daily pattern for weekdays and Sundays, similar, but lagged, to total particle count cycle. Mixing layer depth resulted the main process controlling PM2.5, although also human activities contribute to PM2.5 concentration and allow some deposition and (re-)mobilisation at the first hours of the day and morning rush hour, respectively, while particle number concentration responds immediately to anthropogenic sources. PCA confirmed the dependence of particle number concentration also on meteorological variables, e.g. mixing layer height, wind speed or atmospheric pressure, showing the important influence of regional meteorology on local pollution conditions. Modena can be considered a representative test area of the effect of the meteorological regime for the Central Po Valley on atmospheric particle concentration patterns, characterised by steady high-background concentration. 相似文献
205.
Renato Gerdol Alessandro Pontin Marcello Tomaselli Laura Bombonato Lisa Brancaleoni Matteo Gualmini Alessandro Petraglia Chiara Siffi Alessandro Gargini 《CATENA》2011,86(2):86-97
We examined how hydrology influenced water chemistry, vegetation, nutrient status, aboveground net primary production (ANPP) and litter decomposition rates in two mires on the South-Eastern Alps of Italy. One of the mires had a modest hydraulic gradient and prevalently acted as a recharge system, although there were short phases of vertical flow reversal during dry periods. This mire was, therefore, prevalently fed by rainwater and was covered by bog-like vegetation, mainly hummocks and scrubs with a ground layer rich in Sphagnum mosses. The other mire presented a steeper hydraulic gradient, with the surface being fed by mineral water either by surface runoff or by vertical, upwards directed ground water flow. Compared to the bog-dominated mire, the pore water was less acidic and richer in telluric cations. This mire was covered by fen-like vegetation, prevalently fen meadows. Nitrogen (N) content in the vegetation was very similar in the two mire sites, while phosphorus (P) content was lower in the fen-dominated site. Contrary to our expectations, ANPP did not differ significantly between the two mire sites while litter decomposition rates were significantly lower in the fen-dominated mire, presumably because of P limitation of decomposers. This suggests that the development of ombrogenous mires in this region need not be due to increased accumulation of peat during succession from mineralwater-fed to rainwater-fed conditions. 相似文献
206.
Minelli A 《Science (New York, N.Y.)》2004,306(5702):1693-1694
207.
Mundell CG Steele IA Smith RJ Kobayashi S Melandri A Guidorzi C Gomboc A Mottram CJ Clarke D Monfardini A Carter D Bersier D 《Science (New York, N.Y.)》2007,315(5820):1822-1824
We report the optical polarization of a gamma-ray burst (GRB) afterglow, obtained 203 seconds after the initial burst of gamma-rays from GRB 060418, using a ring polarimeter on the robotic Liverpool Telescope. Our robust (2sigma) upper limit on the percentage of polarization, less than 8%, coincides with the fireball deceleration time at the onset of the afterglow. The combination of the rate of decay of the optical brightness and the low polarization at this critical time constrains standard models of GRB ejecta, ruling out the presence of a large-scale ordered magnetic field in the emitting region. 相似文献
208.
Plaut JJ Picardi G Safaeinili A Ivanov AB Milkovich SM Cicchetti A Kofman W Mouginot J Farrell WM Phillips RJ Clifford SM Frigeri A Orosei R Federico C Williams IP Gurnett DA Nielsen E Hagfors T Heggy E Stofan ER Plettemeier D Watters TR Leuschen CJ Edenhofer P 《Science (New York, N.Y.)》2007,316(5821):92-95
The ice-rich south polar layered deposits of Mars were probed with the Mars Advanced Radar for Subsurface and Ionospheric Sounding on the Mars Express orbiter. The radar signals penetrate deep into the deposits (more than 3.7 kilometers). For most of the area, a reflection is detected at a time delay that is consistent with an interface between the deposits and the substrate. The reflected power from this interface indicates minimal attenuation of the signal, suggesting a composition of nearly pure water ice. Maps were generated of the topography of the basal interface and the thickness of the layered deposits. A set of buried depressions is seen within 300 kilometers of the pole. The thickness map shows an asymmetric distribution of the deposits and regions of anomalous thickness. The total volume is estimated to be 1.6 x 10(6) cubic kilometers, which is equivalent to a global water layer approximately 11 meters thick. 相似文献
209.
Concetta Maria Messina Rosaria Arena Simona Manuguerra Giuseppe Renda Vincenzo Alessandro Laudicella Giovanna Ficano Gioacchino Fazio Laura La Barbera Andrea Santulli 《Marine drugs》2021,19(3)
This study shows a pilot scale protocol aimed to obtain an omega 3-enriched oil after the processing of farmed gilthead sea bream viscera (SBV); this was oil was tested in vitro for bioactivity, attesting to the possibility to turn waste into profit The quality of the oil, in terms of requirements for animal and human consumption, was assessed by determining some chemical parameters, such as peroxide value (PV), thiobarbituric acid reactive substances (TBARS), ρ-anisidine (ρ-AV) content, total oxidation value (TOTOX), and phospholipids and free fatty acid (%), both in crude viscera oil (CVO) and refined viscera oil (RVO). Among the extraction conditions, the higher CVO yields were obtained at 60 °C for 10 min (57.89%) and at 80 °C for 10 min (67.5%), and the resulting oxidation levels were low when utilizing both extraction conditions. RVO, obtained from CVO extracted at 60 °C, showed the highest quality on the basis of the assessed parameters. The ethyl esters of the total fatty acid (TFA) contents extracted from RVO were enriched in the ω-3 polyunsaturated fatty acid fraction (PUFAE) up to almost 56% via short path distillation (SPD). Antioxidant activities and adipogenic properties were tested in vitro. PUFAE protected 3T3 L1 cells from oxidative stress and exerted an anti-adipogenic effect in Dicentrarchus labrax pre-adipocytes, attesting to the beneficial properties for both farmed fish and human health. These results could stimulate the adoption of solutions aimed to recover and utilize aquaculture by-products at a higher scale, turning “waste into profit” and indicating a strategy to reach more sustainable business models in aquaculture resource utilization according to the principles of the circular economy. 相似文献
210.
Vincenzo Sorrenti Davide Augusto Castagna Stefano Fortinguerra Alessandro Buriani Giovanni Scapagnini Donald Craig Willcox 《Marine drugs》2021,19(6)
Spirulina microalgae contain a plethora of nutrient and non-nutrient molecules providing brain health benefits. Numerous in vivo evidence has provided support for the brain health potential of spirulina, highlighting antioxidant, anti-inflammatory, and neuroprotective mechanisms. Preliminary clinical studies have also suggested that spirulina can help to reduce mental fatigue, protect the vascular wall of brain vessels from endothelial damage and regulate internal pressure, thus contributing to the prevention and/or mitigating of cerebrovascular conditions. Furthermore, the use of spirulina in malnourished children appears to ameliorate motor, language, and cognitive skills, suggesting a reinforcing role in developmental mechanisms. Evidence of the central effect of spirulina on appetite regulation has also been shown. This review aims to understand the applicative potential of spirulina microalgae in the prevention and mitigation of brain disorders, highlighting the nutritional value of this “superfood”, and providing the current knowledge on relevant molecular mechanisms in the brain associated with its dietary introduction. 相似文献