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1.
Purpose
Recent trends in soil green and sustainable remediation require an increased attention on environmental effects. The physical consequences of remediation practices on soil structure are very rarely investigated.Material and methods
A laboratory experiment was carried out by adding iron grit to a sand (S), a silt loam (L), and a clay (C) soil subjected to several wetting-drying cycles. The physical effects of the treatment on soil pore system were identified and quantified combining physical measurements on repacked samples with image analysis of pores on resin-impregnated soil blocks and micromorphological analysis on thin sections.Results and discussion
A negligible reduction of total porosity (P) resulted in S, and a slight increase was observed in the L and C soils. However, an important impact on soil structure was identified in pore size range >10 μm for the L and C soils, with the formation of new pores related to the differential shrink-swell behavior between soil matrix and added iron grains. Different plasticity of these soils also played a role in planar pore formation.Conclusions
Effects of the addition of iron grit on soil pore system are strongly dependent on soil physical properties. The performed experiment showed that iron-based amendments can improve soil structure in low-plastic shrink-swell soil increasing porosity in the range of transmission pores (50–500 μm). This study showed the high potential of soil micromorphology and pore image analysis in order to evaluate the environmental impact of soil remediation practices. 相似文献2.
Alessandra Francini Giacomo Lorenzini Cristina Nali 《Water, air, and soil pollution》2011,219(1-4):459-472
A study was conducted to evaluate the effect of pinolene-based film-forming Vapor Gard (VG) emulsion (di-1-p-menthene), a commercial antitranspirant, on the response of the sensitive bean (Phaseolus vulgaris cv. Pinto) plants to realistic ozone fumigations. Plants treated with the chemical were significantly less damaged in comparison with untreated controls when exposed to as much as 150 ppb of ozone in the atmosphere for 4 h. In unozonated plants, photosynthesis as well as stomatal conductance was significantly depressed by the antitranspirant. In VG-treated individuals, (1) visible injury is strongly reduced; (2) membrane damage is counteracted; (3) photosynthetic activity is unchanged, as well as the stomatal conductance and the store of CO2 in substomatal chamber; (4) F v/F m and the other parameters of chlorophyll fluorescence reveal a stability of the photochemical apparatus; and (v) antioxidant defence is not stimulated. Unexpectedly, our results highlighted a dramatic difference between the protective effects towards ozone damage induced by VG, depending on its mode of distribution. As reported above, when entire plants (??both leaves??) are treated or untreated with VG, those individuals wherein VG was not applied showed severe alterations in phenomenological, biochemical and ecophysiological parameters investigated due to ozone toxicity. This is not true in the cases where ??single primary leaves?? or selected regions (??half leaves??) are treated with VG. Even if visible injury is present after ozone fumigation, physiological parameters, such as A max and G w, in ozonated and VG-treated single leaves and half leaves are similar to unfumigated controls. Similar results were obtained for chlorophyll fluorescence parameters. A membrane-protective action is observed in half-leaves treatment. It appears that the presence of regions (single leaves or half leaves), which are treated with VG, modifies the behaviour to ozone of untreated regions. Possible explanations of the observed phenomenon are discussed. The antitranspirant di-1-p-menthene proved to be a low-cost, low-technology tool for assessing ozone injury in the field. 相似文献
3.
Cavaletto Giacomo Faccoli Massimo Marini Lorenzo Spaethe Johannes Giannone Filippo Moino Simone Rassati Davide 《Journal of pest science》2021,94(3):871-883
Journal of Pest Science - Longhorn beetles are commonly moved among continents within wood packaging materials used in trades. Visual inspections carried out at points of entry often fail to detect... 相似文献
4.
Evidence for ozone formation in human atherosclerotic arteries 总被引:1,自引:0,他引:1
Wentworth P Nieva J Takeuchi C Galve R Wentworth AD Dilley RB DeLaria GA Saven A Babior BM Janda KD Eschenmoser A Lerner RA 《Science (New York, N.Y.)》2003,302(5647):1053-1056
Here, we report evidence for the production of ozone in human disease. Signature products unique to cholesterol ozonolysis are present within atherosclerotic tissue at the time of carotid endarterectomy, suggesting that ozone production occurred during lesion development. Furthermore, advanced atherosclerotic plaques generate ozone when the leukocytes within the diseased arteries are activated in vitro. The steroids produced by cholesterol ozonolysis cause effects that are thought to be critical to the pathogenesis of atherosclerosis, including cytotoxicity, lipid-loading in macrophages, and deformation of the apolipoprotein B-100 secondary structure. We propose the trivial designation "atheronals" for this previously unrecognized class of steroids. 相似文献
5.
La Pera L Lo Curto S Visco A La Torre L Dugo G 《Journal of agricultural and food chemistry》2002,50(11):3090-3093
Derivative potentiometric stripping analysis (dPSA) was utilized to evaluate the Cd(II), Cu(II), Pb(II), and Zn(II) content in olive oil samples produced in Sicily in the crop year 2000-2001. The repeatability of the method was attested at 86.36% for cadmium, at 94.94% for copper, at 99.00% for lead, and at 98.92% for zinc. Recovery tests were carried out, both on cleanup procedures and on extraction steps, on olive oil spiked at different levels; obtained recoveries were 84.52 +/- 9.86 for cadmium, 97.34 +/- 2.72 for copper, 100.68 +/- 0.67 for lead and 83.35 +/- 1.72 for zinc. Theoretic detection limits were 1.2 ng g(-1) for Cd, 3.6 ng g(-1) for Cu, 5.9 ng g(-1) for Pb, and 14.3 ng g(-1) for Zn. Found concentrations range were 15.94-58.51 ng g(-1) for Cu, 32.64-156.48 ng g(-1) for Pb, and 157.00-385.22 ng g(-1) for Zn. Copper, lead, and zinc were found in all samples. The main advantage of this determination consists of a not too aggressive metals extraction procedure using hydrochloric acid, which avoids losses of elements typical of sample calcinations methods. 相似文献
6.
Martina Fabbi Antonella Volta Fausto Quintavalla Elena Zubin Sabrina Manfredi Filippo M. Martini Luciana Mantovani Mario Tribaudino Giacomo Gnudi 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(12):1163-1166
A 7-year-old dog was presented with a history of an open lesion on the right thoracic wall, discharging honey-like fluid and small stones. Ultrasonography and computed tomographic fistulography identified a cholecystocutaneous fistula; cholecystectomy was curative. Veterinarians should consider this disease in patients with long-term discharging lesions on the right thoracic or abdominal wall. 相似文献
7.
Characterization of dinucleotide and trinucleotide EST-derived microsatellites in the wheat genome 总被引:6,自引:0,他引:6
Over the past decade microsatellites or simple sequence repeats (SSRs) have attracted a considerable amount of attention from
researchers. The aim of the present paper was to analyse expressed sequence tag-derived SSR (EST-SSR) marker variability in
wheat and to investigate the relationships between the number and type of repeat units and the level of microsatellite polymorphism.
Two hundred and forty-one new EST-SSR markers available in a public database () were characterized in eight durum wheat cultivars (Svevo, Ciccio, Primadur, Duilio, Meridiano, Claudio, Latino, Messapia),
two accessions of Triticum turgidum var. dicoccoides (MG4343, MG29896), one accession of T. turgidum var. dicoccum (MG5323) and in the common wheat cv. Chinese Spring. Of these, 201 primer pairs (83.4%) amplified PCR products successfully,
while the remaining 40 (16.6%) failed to amplify any product. Of the EST-SSRs analysed, 45.2% of the primer pairs amplified
one or two PCR products. Multiple discrete PCR products were observed among both di- and trinucleotide EST-SSR markers (31.2
and 40.5%, respectively). Markers based on dinucleotide microsatellites were more polymorphic than those based on trinucleotide
SSRs in the 12 wheat genotypes tested (68.9 and 52.7%, respectively). An average of 2.5 alleles for dinucleotide and 2.0 alleles
for trinucleotide SSRs was observed. The data reported in the present work indicate the presence of a significant relationship
between motif sequence types and polymorphism. The primer set based on the AG repeat motif showed the lowest percentage of
polymorphism (55.0%), while the primer set based on the AC repeat motif showed t he highest percentage (85.0%). Among trinucleotide
SSRs, the AGG microsatellite markers showed the highest percentage of polymorphism (70.0%), and the ACG motif the lowest value
(25.0%). The characterization of these new EST-SSR markers and the results of our studyon the effect of repeat number and
type of motifs could have important applications in the genetic analysis of agronomically important traits, quantitative trait
locus discovery and marker-assisted selection. 相似文献
8.
Paolo Menesatti Federico Pallottino Giacomo Lanza Graziella Paglia 《Postharvest Biology and Technology》2009,51(3):434-436
A study was conducted to evaluate a non-destructive method able to predict Magness–Taylor (MT) penetrometric firmness of blood oranges, potentially applicable for on-line selection. The method consisted of multivariate modelling of non-destructive penetrometric measurements performed on intact oranges with a 11.3 mm diameter probe by digital dynamometric equipment. The tests were carried out on 366 blood oranges (Citrus sinensis (L.) Osbeck cv. Tarocco); 60 were used as a control group to verify the non-destructive nature of the tests. Four test factors were used on the fruit: two different levels of non-destructive deformation (1 and 3 mm), at two different deformation speeds (5 and 30 mm s?1). In order to obtain the reference parameter (MT firmness), a destructive penetrometric test followed each non-destructive deformation on the same fruit (deformation of 20 mm at 1 mm s?1). The force–deformation curves of the non-destructive tests were elaborated to calculate different texture parameters (max force, elasticity, work). These parameters with raw curve data (force values for constant deformation steps) were used, after autoscaling pre-processing, as X-block datasets in supervised multivariate modelling (partial least squares) to predict MT firmness values. Among the test factors used, the 30 mm s?1 speed and 3 mm deformation provided the best overall prediction of MT firmness. This comprised an r value of 0.76 and standard error of prevision (SEP) of 2.99 N for a MT firmness mean value of 35.65 N (8.4%). The time needed to apply the selected deformation may lead to a sorting speed of about 10 fruit per second, representing an acceptable value for commercial application. 相似文献
9.
10.
Giacomo Lorenzini Alessandra Panattoni Giorgio Schenone 《Water, air, and soil pollution》1988,42(1-2):47-56
Experiments were carried out to investigate, under controlled conditions, the effects of acid smut emitted by oil-fired power plants. The foliar response of 31 selected plant species was ranked and marked differences in sensitivity were observed. Anatomical features of the foliar lesions were described. The toxicity of smuts was largely dependent on their acidity and size. Toxicity was related to temperature but was completely independent of relative humidity in the range from 50 to 90%. No interactive effects were observed between acid smuts and some commercial fungicides, or treatments with asymptomatic concentrations of So2 in fumigation chambers. Some growth parameters were negatively affected by acid smuts in radish. 相似文献