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31.
Venkatesh Uddameri Stephen A. Norton Jeffrey S. Kahl John P. Scofield 《Water, air, and soil pollution》1995,79(1-4):131-146
A paired watershed manipulation study was conducted to study the qualitative and quantitative impacts of elevated acidic precipitation on the chemistry of soils, soil water, and stream water. The Bear Brook Watershed, Maine (BBWM) is drained by two first order streams, East Bear Brook and West Bear Brook. The streams were chemically and hydrologically monitored for two years (1987–1989) and exhibited similar behavior. The West Bear watershed was then chemically manipulated with the bimonthly addition of (NH4)2SO4 (150 mol ha?1 per application). To assess whether changes in stream water chemistry occurred following the chemical manipulation, and if so when, Randomized Intervention Analysis (RIA) was performed using time-paired data from the two watersheds. RIA, along with autocorrelation analysis, statistically evaluates the behavior of the various analytes under the influence of artificial acidification and therefore provided an objective basis for determining whether changes in the geochemical behavior of West Bear Brook were temporally associated with the chemical manipulation. RIA analysis using weekly data yielded higher probabilities of stream water chemistry effects being temporally linked with the manipulation than RIA analysis using monthly data. Using monthly data, there is a lower probability that short-term excursions in water chemistry related to hydrology can be detected. According to RIA analysis of weekly data for three years of manipulation (1989–1992), the statistically-determined order of impact on water chemistry was (K+, Mg2+, Na+, Ca2+, total Al, pH, SO 4 2? , NO 3 ? , DOC)>Si>Cl?. Autocorrelation analysis indicated that several analytes exhibited increasingly deterministic behavior, including SO 4 2? , base cations, and DOC. Both RIA and autocorrelation analysis indicated no temporal relationship between the manipulation and hydrology. 相似文献
32.
Stefano?CanaliEmail author Alessandra?Trinchera Francesco?Intrigliolo Letizia?Pompili Luigi?Nisini Stefano?Mocali Biagio?Torrisi 《Biology and Fertility of Soils》2004,40(3):206-210
A 6-year study was conducted in an organically managed orange orchard located in Sicily (Southern Italy) to assess the effect of compost and organic fertiliser utilisation on soil quality. Adopting a randomised-block experimental design with three replicates, four treatments were carried out. In treatments 1 and 2, two different composts (C1 from distillery by-products and C2 from livestock waste) were applied. The plots of treatment 3 were fertilised using dried poultry manure. The control treatment was fertilised by mineral/synthetic fertilisers. In order to verify the hypothesis that composts and organic fertilisers improve soil fertility, soil quality was evaluated by selecting dynamic soil parameters, as indicators linked to C and N cycles. Total organic C, total N, C/N ratio, humified fraction, isoelectric focussing (IEF) of extracted organic matter, microbial biomass C, potentially mineralisable N under anaerobic conditions, potentially mineralisable C, C mineralisation quotient and metabolic quotient were determined for each sample. Moreover, the Community Level Physiological Profile (by Biolog technique) was defined, calculating derived functional biodiversity and versatility indexes. Parameters related to IEF and potentially mineralisable C showed significant differences among the treatments. Moreover, total C, total N and humification parameters tended to increase, while no differences were observed in biodiversity indexes. On these findings, it was concluded that composts and poultry manure only weakly affected soil properties, though they increased soil potentially available nutritive elements to crops. 相似文献
33.
Rangel A Domont GB Pedrosa C Ferreira ST 《Journal of agricultural and food chemistry》2003,51(19):5792-5797
The major storage globulins (vicilins) of cowpea (Vigna unguiculata) and pea (Pisum sativum) seeds were purified by ammonium sulfate precipitation, and a semipurified cowpea protein isolate (CPI) was prepared by isoelectric precipitation. Some of the functional properties of these proteins, including solubility, foaming, and emulsifying capacities, were investigated and compared. The solubility of purified cowpea vicilin was reduced at pH 5.0, increasing markedly below and above this value. Pea vicilin exhibited poor solubility between pH 5.0 and pH 6.0, and CPI was little soluble in the pH range from 4.0 to 6.0. At neutral pH, the emulsifying activity indexes (EAI) of purified pea vicilin and CPI were 194 and 291 m(2)/g, respectively, which compare quite favorably to EAIs of 110 and 133 m(2)/g for casein and albumin, respectively. Remarkably, purified cowpea vicilin exhibited an EAI of 490 m(2)/g, indicating a very high emulsifying activity. Purified cowpea and pea vicilins exhibited lower foaming capacities and foam stablity indexes (FSI) than CPI. FSI values of 80 and 260 min were obtained for purified pea and cowpea vicilin, respectively, whereas a FSI value of 380 min was obtained for CPI. These results are discussed in terms of the possible utilization of purified vicilins or protein isolates from pea and cowpea in the food processing industry. 相似文献
34.
Aiuti A Slavin S Aker M Ficara F Deola S Mortellaro A Morecki S Andolfi G Tabucchi A Carlucci F Marinello E Cattaneo F Vai S Servida P Miniero R Roncarolo MG Bordignon C 《Science (New York, N.Y.)》2002,296(5577):2410-2413
Hematopoietic stem cell (HSC) gene therapy for adenosine deaminase (ADA)-deficient severe combined immunodeficiency (SCID) has shown limited clinical efficacy because of the small proportion of engrafted genetically corrected HSCs. We describe an improved protocol for gene transfer into HSCs associated with nonmyeloablative conditioning. This protocol was used in two patients for whom enzyme replacement therapy was not available, which allowed the effect of gene therapy alone to be evaluated. Sustained engraftment of engineered HSCs with differentiation into multiple lineages resulted in increased lymphocyte counts, improved immune functions (including antigen-specific responses), and lower toxic metabolites. Both patients are currently at home and clinically well, with normal growth and development. These results indicate the safety and efficacy of HSC gene therapy combined with nonmyeloablative conditioning for the treatment of SCID. 相似文献
35.
Della Torre A Pombi M Petrarca V Coluzzi M 《Science (New York, N.Y.)》2011,332(6028):419-20; author reply 420-1
36.
Rota A Pregel P Cannizzo FT Sereno A Appino S 《Journal of Feline Medicine and Surgery》2011,13(6):448-450
This report describes an unusual case of uterine stump pyometra in a cat whose main clinical sign at presentation was abdominal straining. At the time of ovariohysterectomy, the surgeon reported that the uterine body had a purulent content. Nearly a month after the surgery the cat showed abdominal straining. The enlarged uterine stump, filled with purulent fluid, had caused a compression of the rectum and secondary intestinal sub-occlusion. Surgical revision consisted of draining the purulent content of the remnant of the uterine body and ablating as much of it as possible; checking of the ovarian pedicles revealed the presence of a small fragment of whitish tissue on the right side, which was shown to contain, by means of histological observation and immunohistochemical staining, ovarian tissue. Four months after surgical revision the queen did not show any pathological signs and 1 year later she is still in good health. 相似文献
37.
Korbinian Pieper Tibor Schuster Olivier Levionnois Ulrike Matis Alessandra Bergadano 《Veterinary journal (London, England : 1997)》2011,187(3):335-341
To assess the antinociceptive efficacy of transdermal (TD) buprenorphine (B) in dogs, a prospective, positive-controlled experimental study was performed in 10 healthy Beagles. In an open label crossover design, the dogs initially received intravenous B (IVB, 0.02 mg kg?1) as a positive control, followed by TDB (52.5 μg h?1) 4 months later. Blood was collected at regular intervals for determination of the plasma concentrations of B ([B]) and its metabolite norbuprenorphine. The antinociceptive efficacy was assessed using thermal and mechanical models of nociception. The peak concentration [B] was 1.54 ng mL?1 (±1.98) 60 h after TDB application, although three dogs had no measurable [B] after TDB. Maximum thermal threshold (TT) was 52.6 °C (±0.48) at 1 h after IVB administration and 51.63 °C (±1.01) 72 h after TDB application. The significant increase in TT indicated that effective antinociception was achieved beyond 36 h after the application of TDB, lasting until patch removal. There was hysteresis between [B] and the antinociceptive effect. 相似文献
38.
Lanteri G Sfacteria A Macri D Reale S Marino F 《Journal of zoo and wildlife medicine》2011,42(2):309-312
Penicillium mycosis, or penicilliosis, is rare in animals. This report describes the clinical signs and pathological, immunohistochemical, and biomolecular findings in a case of avian penicilliosis in a Congo African grey parrot. On gross necropsy, pyogranulomatous changes were identified in the lung, liver, and kidney. Histopathology demonstrated periodic acid Schiff-(PAS) and Grocott-positive hyphae in these tissues. Immunohistochemistry confirmed the genus of the fungus and polymerase chain reaction (PCR) confirmed a high homology with Penicillium chrysogenum. 相似文献
39.
Fratianni A Irano M Panfili G Acquistucci R 《Journal of agricultural and food chemistry》2005,53(7):2373-2378
Color is an important parameter involved in the definition of semolina and pasta quality. This character is mainly due to natural pigments (carotenoids) that are present at different levels in cereals and cereal products, due to botanical origin, growing conditions, distribution in the kernel, and technological processes. In food industries, color measurements are usually performed by means of automatic instruments that are rapid and safe, as alternatives to the chemical extraction methods. In this study, automatic measurements (CIE, color-space system L, a, b), water-saturated butanol (WSB), and HPLC determinations have been applied to evaluate the carotenoid content in whole meals and respective semolina samples produced from wheat cultivated in the years 2001 and 2002. In whole meals, total carotenoids, determined by HPLC, were about 3.0 microg/g (2001) and 3.5 microg/g (2002) calculated on dry weight (dw) and about 3.0 and 3.2 microg/g dw in corresponding semolina samples. The b values for the same period were 19.78 and 15.75, respectively, in raw materials and 20.03-21.67 in semolina. Results have confirmed lutein and beta-carotene as the main components mainly responsible for the yellow color in wheat grains. The ability of the index b to express natural dyeing was dependent on sample characteristics as demonstrated by the relationships found between this index and pigments, although the best correlation resulted between HPLC and WSB. 相似文献
40.
Supercritical carbon dioxide extraction and characterization of Laurus nobilis essential oil 总被引:5,自引:0,他引:5
Caredda A Marongiu B Porcedda S Soro C 《Journal of agricultural and food chemistry》2002,50(6):1492-1496
Supercritical carbon dioxide extraction allowed essential oil of Laurus nobilis to be obtained. Extraction conditions were as follows: pressure, 90 bar; temperature, 50 degrees C; and carbon dioxide flow, Phi = 1.0 kg/h. Waxes were entrapped in the first separator set at 90 bar and -10 degrees C. The oil was recovered in the second separator working at 15 bar and 10 degrees C. The main components were 1,8-cineole (22.8%), linalool (12.5%), alpha-terpinyl acetate (11.4%), and methyleugenol (8.1%). Comparison with the hydrodistilled oil did not reveal any significant difference. Collection of samples at different extraction times during supercritical extraction allowed the change of the oil composition to be monitored. Lighter compounds such as hydrocarbon and oxygenated monoterpenes were extracted in shorter times than the heavier hydrocarbon and oxygenated sesquiterpenes. 相似文献