Determination of selenium content in different types of seed oils by cathodic stripping potentiometry (CSP)     

Dugo G  La Pera L  Pollicino D  Saitta M 《Journal of agricultural and food chemistry》2003,51(19):5598-5601

Seed oils are consumed worldwide; moreover, they are used in the alimentary, cosmetic, pharmaceutical, and chemical industries. Due to their diffusion, it is interesting to investigate the presence of important micronutrients such as selenium in seed oils. The aim of this work was to develop a rapid, precise, and sensitive cathodic stripping potentiometry (CSP) method to determine the concentration of selenium in different types of seed oils. Selenium was extracted from the oily matrix by concentrated hydrochloric acid treatment at 90 degrees C. The analysis was executed by applying an electrolysis potential of -150 mV for 60 s and a constant current of -30 microA. Under these conditions, detection limits of <0.5 ng g(-1) were obtained. The method reproducibility (expressed as total RSD %) spanned from 0.2 to 0.8%. Recoveries ranged from 92.1 to 97.5%, providing evidence that selenium quantification remained unaffected by the extraction procedure described. The results obtained with the proposed method were compared with those obtained via graphite furnace atomic absorption spectroscopy (GFAAS), a common method for determining selenium. The results of the two methods agreed within 93.5-107.7%. The mean amounts of selenium found were 313.0 +/- 2.0, 458.3 +/- 1.3, 224.6 +/- 0.9, 99.5 +/- 0.8, 332.2 +/- 0.5, 144.0 +/- 0.7, and 295.5 +/- 1.2 ng g(-1), respectively, in peanut, soybean, sunflower, rice, corn, grapestone, and seed oils.  相似文献   

The effect of pharmaceutical waste-fungal biomass,treated to degrade DNA,on the composition of eubacterial and ammonia oxidizing populations of soil     

Maria Teresa Ceccherini  Judith Ascher  Giacomo Pietramellara  Stefano Mocali  Carlo Viti  Paolo Nannipieri 《Biology and Fertility of Soils》2007,44(2):299-306

The aim of this work was to study variations in the composition of eubacteria and ammonia-oxidizing populations of soil, both determined by denaturing gradient gel electrophoresis (DGGE), after the addition of a pharmaceutical fungal biomass, treated to degrade its DNA. This waste can be used as an amendment. The fungal biomass waste was added at three rates: 0.05, 0.1, and 1% per dry weight of soil. Control soil, without any amendment, was also investigated. Total DNA was extracted, purified, and amplified by using either universal (eubacteria) or specific (amoA) primers. Amplicons were separated by DGGE. Sequencing was also carried out to better assess the diversity of ammonia oxidizing bacteria. Changes in the composition of eubacterial community were detected after 3 days only in the soil treated with the highest dose, while the ammonia oxidizing population responded more promptly (after 1 day) with evident modifications at level of Nitrosolobus like sequences.  相似文献   

ECHOGRAPHIC EXAMINATION OF THE STIFLE JOINT AFFECTED BY CRANIAL CRUCIATE LIGAMENT RUPTURE IN THE DOG     

Giacomo  Gnudi  Dr  Vet  Med  Giorgio  Bertoni  Prof  Dr  Vet  Med 《Veterinary radiology & ultrasound》2001,42(3):266-270

Ultrasound is a useful technique for the study of normal and pathologic stifle joints, in particular for soft tissue examination. The aim of this study was to evaluate sonography for examination of stifle joints affected by cranial cruciate ligament rupture. Forty-two medium to giant breed dogs were studied. Tibial compression radiography was performed. A 7.5 MHz transducer with an incorporated 2 cm thick standoff was employed. Sagittal and midsagittal images were collected. The stifle was positioned in maximum flexion during sonography. Sonographic findings were compared with pathologic findings at surgery. Ultrasound was useful in evaluating the presence of fibrous tissue within the joint due to repair processes. It was observed in 70% of stifles with radiographic evidence of chronic osteoarthritis. In 19.6% of the joints it was possible to identify the ruptured cranial cruciate ligament. Ultrasound was not an accurate test for cruciate rupture evaluation, but was specific for the soft tissue pathologic changes which were observed consequent to joint instability.  相似文献   

Long‐Term Durum Wheat‐Based Cropping Systems Result in the Rapid Saturation of Soil Carbon in the Mediterranean Semi‐arid Environment     

Agata Novara  Ignazio Poma  Mauro Sarno  Giacomo Venezia  Luciano Gristina 《Land Degradation \u0026amp; Development》2016,27(3):612-619

Climate, soil physical–chemical characteristics, land management, and carbon (C) input from crop residues greatly affect soil organic carbon (SOC) sequestration. According to the concept of SOC saturation, the ability of SOC to increase with C input decreases as SOC increases and approaches a SOC saturation level. In a 12‐year experiment, six semi‐arid cropping systems characterized by different rates of C input to soil were compared for ability to sequester SOC, SOC saturation level, and the time necessary to reach the SOC saturation level. SOC stocks, soil aggregate sizes, and C inputs were measured in durum wheat monocropping with (Ws) and without (W) return of aboveground residue to the soil and in the following cropping systems without return of aboveground residue to soil: durum wheat/fallow (Wfall), durum wheat/berseem clover, durum wheat/barley/faba bean, and durum wheat/Hedysarum coronarium. The C sequestration rate and SOC content were lowest in Wfall plots but did not differ among the other cropping systems. The C sequestration rate ranged from 0.47 Mg C ha⁻¹ y⁻¹ in Ws plots to 0.66 Mg C ha⁻¹ y⁻¹ in W plots but was negative (−0.06 Mg C ha⁻¹ y⁻¹) in Wfall plots. Increases in SOC were related to C input up to a SOC saturation value; over this value, further C inputs did not lead to SOC increase. Across all cropping systems, the C saturation value for the experimental soil was 57.7 Mg ha⁻¹, which was reached with a cumulative C input of 15 Mg ha⁻¹. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Seasonal and interannual variability of photosynthetic capacity in relation to leaf nitrogen in a deciduous forest plantation in northern Italy     

Grassi G  Vicinelli E  Ponti F  Cantoni L  Magnani F 《Tree physiology》2005,25(3):349-360

Gas exchange was measured in a forest plantation dominated by Fraxinus angustifolia Vahl. and Quercus robur L. in northern Italy, over three growing seasons that differed in water availability (2001, 2002 and 2003). The objectives were to: (1) determine variability in the photosynthetic parameters V(cmax) (maximum carboxylation capacity) and J(max) (maximum rate of electron transport) in relation to species, leaf ontogeny and drought; and (2) assess the potential of the photosynthesis-nitrogen relationship for estimating leaf photosynthetic capacity. Marked seasonal and interannual variability in photosynthetic capacity was observed, primarily caused by changes in leaf ontogeny and water stress. Relatively small differences were apparent between species. In the absence of water stress (year 2002), the seasonal patterns of V(cmax) and J(max) were characterized by a rapid increase during spring, a relatively steady state during summer and a rapid decline during autumn. In years with a moderate (year 2001) or a severe (year 2003) water stress, photosynthetic capacity decreased during the summer in proportion to drought intensity, without a parallel decline in leaf nitrogen content. The V(cmax)-nitrogen relationship was significantly affected by both leaf ontogeny and drought. As a consequence, the use of a single annual regression to predict V(cmax) from leaf nitrogen yielded good estimates only during the summer and in the absence of water stress. Irrespective of the mechanisms by which photosynthetic capacity is affected by water stress, its large seasonal and interannual variability is of great relevance for modeling the forest carbon cycle.  相似文献   

Photosynthesis-nitrogen relationships: interpretation of different patterns between Pseudotsuga menziesii and Populus x euroamericana in a mini-stand experiment     

Ripullone F  Grassi G  Lauteri M  Borghetti M 《Tree physiology》2003,23(2):137-144

We compared photosynthesis-nitrogen relationships of one broad-leaved (poplar; Populus x euroamericana (Dole) Guinier) and one conifer (Douglas-fir; Pseudotsuga menziesii (Mirb.) Franco) species. Plants were grown in large pots to allow free root development and were kept well watered. We determined effects of low, intermediate and high nitrogen supply rates on area-based leaf nitrogen (Na) and chlorophyll concentrations, leaf mass per area (LMA), light-saturated photosynthesis (Amax), maximum carboxylation (Vcmax) and electron transport rate (Jmax), photosynthetic nitrogen-use efficiency (PNUE), and proportions of leaf N in active Rubisco (PR), bioenergetic pools (PB) and the light-harvesting complex (PLH). Nitrogen supply significantly affected leaf Na. Leaf mass per area did not differ between species and was unaffected by the N treatments. In both species, there was a positive correlation between leaf Na and chlorophyll concentration, and between leaf Na and the photosynthetic parameters Amax, Jmax and Vcmax. At comparable leaf Na, however, poplar showed twofold higher PNUE and a threefold steeper slope of the Amax- nitrogen relationship than Douglas-fir. Leaf Na was negatively correlated with PNUE in Douglas-fir but not in poplar. Leaf Na was also negatively correlated with PR, PB and PLH in Douglas-fir, whereas in poplar, a negative correlation was found only for PLH. Parameter PR was significantly higher in poplar than in Douglas-fir. The ratio of CO2 concentration in the intercellular space to that in ambient air was higher in poplar than in Douglas-fir. Overall, our data suggest that differences in the photosynthesis-nitrogen relationship and PNUE between Douglas-fir and poplar primarily reflect a different investment of N to active Rubisco, and possibly a different constraint to CO2 diffusion.  相似文献   

In‐field detection and quantification of extracellular DNA     

Maria Teresia Ceccherini  Judith Ascher  Giulia Guerri  Giacomo Pietramellara 《植物养料与土壤学杂志》2009,172(5):626-629

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On the Different Sensitivity of White Clover Clones to Ozone: Physiological and Biochemical Parameters in a Multivariate Approach     

Cristina Nali  Chiara Pucciariello  Gina Mills  Giacomo Lorenzini 《Water, air, and soil pollution》2005,164(1-4):137-153

This study analyses the physiological and biochemical basis of chronic ozone exposure (60 ppb for 56 days, 5 h day^?1) on NC-S (sensitive) and NC-R (resistant) white clover clones. Analyses were performed after 0, 14, 28 and 56 days of fumigation which corresponded to AOT40 s of 0, 1400, 2800 and 5600 ppb.h, respectively. NC-S exhibited foliar injury and had a decreased content of photosynthetic pigments, while peroxidized lipids and solute leakage increased, indicating that the plants were subjected to membrane damage. The multivariate approach identified five groups. The NC-R group, with the exception of samples at 0 days of exposure and treated for the longest time period (and thus at the highest dose), and NC-S controls after 28 and 56 days were associated with photosynthetic pigments variables. Ascorbate peroxidase was twinned with NC-R treated at the highest dose. Guaiacol peroxidase and solute leakage was mildly linked with NC-S following ozone treatment for 56 days (AOT40 = 5600 ppb.h).  相似文献   

Pulmonary rhodococcosis in a cat     

Passamonti F  Lepri E  Coppola G  Sforna M  Casagrande Proietti P  Chiodetti I  Coletti M  Marenzoni ML 《Journal of Feline Medicine and Surgery》2011,13(4):283-285

Feline Rhodococcus equi infection is rare, despite the bacteria is widespread in the environment. R equi infection is typically observed in equine species but the infection has also been reported in dogs, cats and other domestic animals. There are a few reports regarding pulmonary R equi infection in cats and the disease appears to be limited to the skin and the subcutaneous tissue. This report describes the pathological, microbiological and the virulence features associated with an acute necrosuppurative pneumonia in a cat. To the best of our knowledge, this is the first report of feline pulmonary R equi infection in Italy.  相似文献   

GPS tracking of foraging albatrosses     

Weimerskirch H  Bonadonna F  Bailleul F  Mabille G  Dell'Omo G  Lipp HP 《Science (New York, N.Y.)》2002,295(5558):1259

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