On Morphometric Properties of DNAPL Sources: Relating Architecture to Mass Reduction   总被引：1，自引：0，他引：1  

Antonella Luciano  Paolo Viotti  Marco Petrangeli Papini 《Water, air, and soil pollution》2012,223(5):2849-2864

The fundamental step in the identification of the most appropriate strategy for the remediation of sites contaminated with dense nonaqueous phase liquids (DNAPLs) is a comprehensive characterization of the contaminated source region as the morphology of DNAPL strongly governs the mass transfer processes. The influence of DNAPL distribution geometry and groundwater flow velocity on mass reduction was explored through the evaluation of a series of laboratory studies conducted in a two-dimensional tank under different hydrodynamic conditions. An image analysis procedure was used to determine the distribution of DNAPL saturation and the morphology of the contaminated region. Experimental observations revealed a dependence of mass transfer rate on the aqueous phase velocity under high flow regimes, whereas the mass transfer rate was controlled mainly by morphometric indexes under low velocity flow conditions. Experimental results indicate that higher mass reduction and contaminant fluxes are obtained at low saturation values. The mass flux emanating from an elongated source aligned perpendicularly to the direction of water flow is greater due to a higher DNAPL?Cwater contact surface in comparison to a lower mass flux from horizontal pools with high saturation. These aspects should be considered in an inverse modeling technique for locating the source zone and also in all remediation approaches based on an increase in water circulation through a contaminated zone (i.e., pump and treat).  相似文献   

Vector analysis in the study of the nutritional status of Philodendron cultivated in compost-based media     

Marco Grigatti  Maria Eva Giorgioni  Luciano Cavani  Claudio Ciavatta 《Scientia Horticulturae》2007

Compost (CP) made from 70% ligno-cellulosic compounds and 30% sewage sludge was studied as a component of growing media in a 6-month Philodendron cultivation. CP's agronomic viability was evaluated via four plant-growth media containing 25–50–75–100% CP and white sphagnum peat (WP) in comparison to a commercial substrate with white and black peat. Plant nutrition conditions were investigated by determining macro- (TKN, P, K, Ca, Mg and micronutrients (Mn, Fe, Cu, Zn, Na) and heavy metals (Ni, Cd, Cr, Pb) in roots and shoot tissues. Data were compared by vector analysis against control. Even if no leaf injuries were visible after 6-months’ growth, a CP ratio of up to 50% caused growth depression of canopy tissues, as attested by the 37 and 36% reduction in total leaf dry weight and leaf area, respectively. Root growth decline was also notable at 25% CP, where 38% root dry weight reduction implied a significant increase (46%) in shoot–root dry weight ratio. The investigation on nutrient tissue content showed high accumulation of Ni, Fe, Cr, Zn, Cd, Mn, Mg and P in roots; Mg appeared related to K deficiency. Above-ground nutritional status showed a severe lack of P, Mg and Mn. Vector analysis suggests the sewage sludge CP in Philodendron pot cultivation produces many such effects like direct toxic action and antagonistic action, resulting in a general nutrient imbalance in plants.  相似文献   

Inducible Expression of a Phytolacca heterotepala Ribosome-Inactivating Protein Leads to Enhanced Resistance Against Major Fungal Pathogens in Tobacco     

Corrado G  Bovi PD  Ciliento R  Gaudio L  Di Maro A  Aceto S  Lorito M  Rao R 《Phytopathology》2005,95(2):206-215

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Anti-leishmanial and immunomodulatory activities of extracts from Portulaca hirsutissima and Portulaca werdermannii     

Costa JF  Kiperstok AC  David JP  David JM  Giulietti AM  de Queiroz LP  dos Santos RR  Soares MB 《Fitoterapia》2007,78(7-8):510-514

Ethyl acetate and chloroform extracts from aerial parts of Portulaca werdermannii and P. hirsutissima were tested in lymphoproliferation assays and axenic cultures of Leishmania amazonensis and Trypanosoma cruzi. Both extracts of P. werdermannii and P. hirsutissima had a potent inhibitory activity on lymphocyte proliferation. On the contrary, only the chloroformic extract of both plants inhibited L. amazonensis growth, without effect on T. cruzi cultures. These results indicate these Portulaca species as potential sources of new active molecules for the treatment of leishmaniasis and immune-mediated pathologies.  相似文献   

The impact of sugarcane filter cake on the availability of P in the rhizosphere and associated microbial community structure     

Bruna Arruda  Marcos Rodrigues  Thiago Gumiere  Alan E. Richardson  Fernando Dini Andreote  Amin Soltangheisi  Luciano Colpo Gatiboni  Paulo Sergio Pavinato 《Soil Use and Management》2019,35(2):334-345

This study aimed to evaluate the interaction between filter cake (FC), and phosphorus fertilizers with differing solubility on the growth and P nutrition of sugarcane. Effects of soil amendment with FC on different soil P fractions and influence on microbial community structure in the rhizosphere were also assessed. Two glasshouse experiments were conducted with completely randomized block designs. The first experiment evaluated rates of FC using a factorial design (5 × 2): 0, 2.5, 5, 10 and 15 g FC kg^?1 soil applied as either broadcast in bulk soil or in the planting furrow. The second experiment used a factorial design (2 × 3): without and with FC (5 g kg^?1 soil, dry basis), both without P (NP) and with P supplied as either triple superphosphate (TSP) or as rock phosphate (RP), both at the rate of 78.4 mg kg^?1 based on total P. Microbial community structure was determined using TRFLP and dynamics of soil P by Hedley fractionation. Filter cake applied at increasing rates in the absence of P was effective in increasing shoot growth and P uptake by plant, particularly when applied to bulk soil as compared to furrow application. Also, FC improved P uptake and increased the availability of labile inorganic P in the rhizosphere and modified the structure of fungal and bacterial communities, whereas only bacterial and archaea communities were influenced by P fertilizer use. Filter cake was more effective when combined with RP, with increased growth and P utilization and thus can be considered as a feasible and practical option for farmer use in substitution to TSP, a more expensive source.  相似文献   

Demethylation of H3K27 regulates polycomb recruitment and H2A ubiquitination   总被引：3，自引：0，他引：3  

Lee MG  Villa R  Trojer P  Norman J  Yan KP  Reinberg D  Di Croce L  Shiekhattar R 《Science (New York, N.Y.)》2007,318(5849):447-450

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Methyltransferase recruitment and DNA hypermethylation of target promoters by an oncogenic transcription factor   总被引：1，自引：0，他引：1  

Di Croce L  Raker VA  Corsaro M  Fazi F  Fanelli M  Faretta M  Fuks F  Lo Coco F  Kouzarides T  Nervi C  Minucci S  Pelicci PG 《Science (New York, N.Y.)》2002,295(5557):1079-1082

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Performance and serum parameters of calves (Bos taurus) subject to milk restriction associated with supplementation with 2-hydroxy-4-(methylthio)butanoic acid     

Rosiane F Brito  Aldi F S Frana  Aline P Pansani  Carlos H Castro  Diego B Colugnati  Luciano F Souza  Luiza A Rabelo  Valria Nunes-Souza  Carlos H Xavier  Graciele A Oliveira  Daniel S Corrêa  Adriano T Ramos  Larissa M Macedo  Reginaldo N Ferreira 《Journal of animal science》2021,99(6)

Our aim with this study was to evaluate the consumption, performance, quantitative characteristics of carcasses, biochemical profile, plasma levels of ghrelin and leptin, expression of the receptor for ghrelin (GHS-R1a) in the hypothalamus and duodenum, and the number of goblet cells in the duodenum of calves subjected to milk volume restriction and supplemented with 2-hydroxy-4-(methylthio)butanoic acid (HMTBa). We used 21 Holstein mixed-breed calves, aged between 3 and 15 d with an average weight of 36.8 kg, and housed in pens with troughs for hay, concentrate, and water. The study included two consecutive experimental periods (first period [P1] and second period [P2]) of 21 d each, with 7 d of adaptation to the diet and facilities. The calves were distributed in a completely randomized design in three treatments with seven repetitions. 1) Control: 6 liters of milk/d during P1 and 6 liters of milk/day during P2; 2) RES (milk restriction): 3 liters of milk/day during P1 and 6 liters of milk/day during P2; and 3) RES + HMTBa: 3 liters of milk/day during P1 and 6 liters of milk/day during P2 + 3.3 g of HMTBa/day in both periods. HMTBa was supplied in milk, and the amount of concentrated ration and hay provided and leftovers were recorded daily to estimate dry matter (DM) and crude protein consumption. Mean daily weight gain (DWG), final weight (FW), and feed conversion (FC) were obtained at the beginning and at the end of each 21-d period. Plasma concentrations of ghrelin and leptin, triglycerides, total protein, urea, lactate, creatinine, alkaline phosphatase, and cholesterol were measured for P1 and P2 at the end of each 21-d period. At the end of P2, animals were slaughtered; sections of the duodenum were collected to evaluate the expression of GHS-R1a and quantity of goblet cells; hypothalamus was used to evaluate the expression of GHS-R1a; rumen was used to evaluate the thickness of epithelium and keratin and the density, height, and width of ruminal papillae. In P1, total DM consumption, FW, DWG, glucose, and triglycerides were lower in the RES and RES + HMTBa groups (P < 0.001). In P2, there was an improvement in the FC of the RES + HMTBa group (compared with Control and RES groups) and a lower urea concentration in the RES group (compared with Control and RES + HMTBa groups) (P < 0.001). No differences were observed among groups regarding hormonal concentrations, histological parameters, and GHS-R1a expression in the duodenum and hypothalamus. Therefore, milk restriction combined with HMTBa supplementation promoted greater compensatory gain by a mechanism independent of changes in GHS-R1a expression and hormone levels of ghrelin and leptin.  相似文献   

Towards More Efficient Incentives for Agri‐environment Measures in Degraded and Eroded Vineyards     

Antonino Galati  Luciano Gristina  Maria Crescimanno  Ettore Barone  Agata Novara 《Land Degradation \u0026amp; Development》2015,26(6):557-564

Evaluating the economic damage caused by soil erosion is important. In addition to increasing the awareness of the problem among farmers and policy makers, evaluation of the economic damage caused by erosion can promote the implementation of more sustainable soil management practices. In the present study, we describe a new approach to evaluate incentives for the adoption of agri‐environment measure (AEM) in degraded and eroded vineyards. To estimate this incentive, the replacement cost (RC) and the loss of income are calculated when the vineyard is managed with conventional tillage versus a cover crop (AEM). Our findings show that the incentive could range from the loss of income due to AEM adoption to the ecosystem service benefit (RC_C − RC_AEM). In our case study, the incentive ranged from 315 € ha⁻¹ (loss of income) to 1,088 € ha⁻¹ (ecosystem service benefit). Within this range, the incentive amount is determined according to efficiency criteria based on vineyard slope. We also present a conceptual model of public spending efficiency that should help policy makers decide how to allocate the incentives so as to maximize the economic return associated with ecosystem services. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

Plant species richness in the Chaco Serrano Woodland from central Argentina: Ecological traits and habitat fragmentation effects     

Luciano Cagnolo  Marcelo Cabido 《Biological conservation》2006,132(4):510-519

The Chaco Serrano Woodland from central Argentina has been dramatically reduced during the past 30 years, and is currently confined to several isolates of different size. In this study, we evaluated the effects of forest size, isolation and edge formation on plant species richness. Furthermore, we tested whether plants species with particular ecological traits were differentially affected by habitat fragmentation. Habitat area showed the highest explanatory value for plant species richness in stepwise multiple regressions. The effect of area was most pronounced for rare species, suggesting that large forests are necessary to preserve species with low local or regional abundance. Differences between edge and interior of Chaco Serrano were more pronounced for native and shrub species richness. The analysis of individual species cover revealed that native and biotically pollinated plants were less abundant in woodland edges. Our results showed that forest transformation into smaller remnants has lead to an impoverishment of plant communities, with particular subsets of species defined by ecological traits (rarity, origin and pollination mode) being more susceptible.  相似文献