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31.
32.
Dejan Krcmar Milena Dalmacija Bozo Dalmacija Miljana Prica Jelena Trickovic Elvira Karlovic 《Journal of Soils and Sediments》2013,13(7):1318-1326
Purpose
The objective of this research was to apply the same immobilization (stabilization/solidification) clay-based treatments to sediment contaminated with different metals (Pb, Cd, Ni, Zn, Cu, Cr) with different distributions and availabilities in sediment. We also examined the possibility of using clay as an immobilization agent without the application of thermal treatment, in order to reduce the economic cost of this expensive remediation procedure.Materials and methods
Clay from a canal in Vojvodina, Republic of Serbia, was used as the immobilization agent in a stabilization/solidification treatment to remediate metal-contaminated sediment. Semi-dynamic and toxicity characteristic leaching tests were conducted to assess the effectiveness of the nonthermal and thermal immobilization treatments with clay, and the long-term leaching behavior of these metals was determined using the following parameters: cumulative percentage of metals leached; diffusion coefficients; leachability indices; and toxicity characteristic leaching test concentration.Results and discussion
Based on these parameters, both clay-based treatments were effective in immobilizing metals in the contaminated sediment. Results suggest that both heating temperature and clay proportion in the sediment–clay mixture impact the degree of metal immobilization.Conclusions
Clay-based products are potentially good immobilization materials for metal-contaminated sediments, with the distribution of metals in the original sediment not influencing the efficacy of the treatments. Even without the thermal treatment, the metals were effectively immobilized. The leaching of metals was largely inside the regulatory limits and the treated samples can be regarded as nonhazardous materials. This justifies the choice of not applying the more expensive thermal treatment during remediation, especially when treating sediments containing a mixture of pollutants. 相似文献33.
Elvira Sereda Theo Blick Wolfgang H.O. Dorow Volkmar Wolters Klaus Birkhofer 《Pedobiologia》2012,55(5):241-245
Describing the biotic and abiotic processes that are responsible for the formation of spatial patterns in predators and their prey is crucial for improving our understanding of food–web interactions. We studied the spatial distribution of four abundant spider species and three common groups of epedaphic Collembola prey in a beech-dominated (Fagus sylvatica) forest floor habitat and related the observed patterns to environmental heterogeneity, overall predator activity (all ground beetles and spiders) and prey availability (all Collembola) at the local scale. Spiders and epedaphic Collembola were sampled over 392 days in a spatially explicit design based on a regular grid of 25 pitfall traps (inter-trap distance 100 m). Environmental heterogeneity was characterized by cover of moss and litter as well as the amount of dead wood at each trap location. We first used the index of dispersion to characterize the spatial distribution of spider species and Collembola and then related the observed patterns to environmental heterogeneity, predator and prey availability while testing for spatial autocorrelation within the same models. All taxa were significantly more aggregated than expected from the assumption of random distribution. The distribution of spider species was positively (Coelotes terrestris) or negatively (Tenuiphantes zimmermanni and Tapinocyba insecta) related to the cover of moss and negatively related to litter cover (C. terrestris) or the local availability of prey (T. insecta). The distribution of Collembola was negatively related to local litter cover (Lepidocyrtus spp.) and positively related to the amount of medium deadwood pieces (all other Entomobryidae). Our study suggests that none of the spider species preferred areas of low overall predator activity density. Moreover, it does not indicate association of spider species to prey-rich areas at the analyzed scale of 100 m. It further highlights the importance of environmental heterogeneity, as different habitat properties differentially affected the local activity density of spiders and Collembola and thus considerably contributed to the understanding of distribution patterns. 相似文献
34.
Marinaro M Tempesta M Tarsitano E Camero M Losurdo M Buonavoglia C Rezza G 《Research in veterinary science》2012,93(2):662-667
The analysis of cytokines secreted by antigen-specific lymphocytes is hampered in goats by the paucity of species-specific reagents yet it is crucial to study immune responses to infections. To overcome this limit, two commercial kits designed to measure soluble bovine IL-4 (by ELISA) and frequencies of bovine IFN-gamma secreting cells (by ELISPOT) were tested for cross-reactivity in goats. In addition, an ELISA specific to bovine/ovine IL-4 and employing two monoclonal antibodies, clones CC313 and CC314, was tested as well. Concanavalin A-stimulated caprine peripheral blood mononuclear cells (PBMCs) cultures were studied and they exhibited high levels of soluble IL-4 and high frequencies of IFN-gamma secreting cells. In addition, the two IL-4 ELISAs detected similar amounts of cytokine. To start defining the cytokine response triggered by caprine herpesvirus 1 (CpHV-1) infection, PBMC cultures were setup from goats naturally or experimentally infected with CpHV-1. High frequencies of IFN-gamma producing cells and low, when detectable, levels of soluble IL-4 were observed in CpHV-1-specific PBMC cultures from both groups of infected goats. Thus, the availability of cross-reactive research tools can expand cytokine studies in goats and can implement the research on immunity to other caprine infections. 相似文献
35.
Tetrasomic plants with two additional small chromosomes were identified, with a frequency about 2.5%, in the trisomic pea
line TRUST-R, which normally contains one extra chromosome covering a sporophyte lethal in the regular chromosome set. As
compared to trisomics, tetrasomics exhibited an enhanced expression of the traits resulting from extra chromosome addition:
slow growth, enlarged bracts, shortened peduncles, wavy leaflets and stipulae. They were almost sterile, their pollen contained
a variable proportion of empty grains and some anomalously large, small or deformed grains. In metaphase I, two extra chromosomes
did not form a stable bivalent and only in some cases were situated close to each other. In anaphase I, the extra chromosomes
migrated independently to either pole or retarded in the equatorial plain, the same was observed for chromatids in anaphase
II. This retardation resulted in anomalous cytokinesis, so that triads, dyads and half-divided or non-divided monads appeared.
The retarded extra chromosomes may form small extra nuclei either included into one of the microspores or forming a separate
miniature cell; in this way tetrasomics may eliminate extra chromosomes. One of the tetrasomics analysed formed an exceptionally
high proportion of microspore pentads. In the regluar TRUST-R trisomics, the sole extra chromosome retarded in the equatorial
plain in anaphases I and II. The retardation in anaphase II often makes cytokinesis in trisomics (in general more regular
than in tetrasomic) to proceed in two steps: at first cell wall formation separates a pollen mother cell into two dyads and
then each of them into two microspores. 相似文献
36.
Chandra-Hioe Maria V. Elvira Jenny Arcot Jayashree 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(1):34-39
Plant Foods for Human Nutrition - Lutein is a xanthophyll, a bioactive phytochemical that presents itself as colourful pigments in plants. Australian sweet lupin flour has been... 相似文献
37.
Frias J Song YS Martínez-Villaluenga C González de Mejia E Vidal-Valverde C 《Journal of agricultural and food chemistry》2008,56(1):99-105
Food allergy has become a public health problem that continues to challenge both the public and the food industry. The objective of this research was the detection and quantification of the major human allergenic soy proteins and to study the reduction in immunoreactivity and improvement of amino acid content after fermentation of soybean flour. Fermentation was carried out in the solid state of cracked seeds inoculated with Aspergillus oryzae, Rhizopus oryzae, and Bacillus subtilis and in the liquid state of milled soybean flours fermented naturally by microorganisms present only in the seeds or by inoculation with Lactobacillus plantarum. ELISA and Western blot were used to quantify IgE antibody response, and HPLC was used to identify and quantify total amino acids. L. plantarum fermented soy flour showed the highest reduction in IgE immunoreactivity (96-99%) depending upon the sensitivity of the plasma used. Among the solid fermented products, the lowest reduction in immunoreactivity was obtained when mold strains, R. oryzae and A. oryzae, were used (66 and 68%, respectively, for human plasma 97.5 kUA/L). Among the solid fermented products, those inoculated with B. subtilis yielded a 81 and 86% reduction in immunoreactivity against both human plasma 97.5 IgE kUA/L and human pooled plasma samples, respectively. When soybean was subjected to liquid fermentation, most of the total amino acids increased significantly ( p < or = 0.05). In solid fermentation with R. oryzae, only Ala and Thr content improved. Fermentation can decrease soy immunoreactivity, and there is potential of developing nutritious hypoallergenic soy products. 相似文献
38.
Diego A. Luna-Vital Elvira González de Mejía Guadalupe Loarca-Piña 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(4):445-447
The aim was to evaluate the antineoplastic potential of a previously characterized peptide extract from the non-digestible fraction of common bean cv. Azufrado Higuera (AH) and its most abundant pure peptide GLTSK, in an azoxymethane/dextran sodium sulfate (AOM/DSS)-induced colitis-associated colon carcinogenesis Balb/c mice model. The healthy control (C-) had no induction and no treatment, and the induced control (C+) had induction but no treatment. Groups AH and GLTSK were administered 50 mg/kg-bw of AH or GLTSK, respectively. The administration of AH and GLTSK decreased (p < 0.05) the disease activity index (DAI) compared to C+ (5.8, 9.1, 11.8, respectively). Furthermore, AH reduced the number of evident neoplasms compared to group C+ (1.8, 5.9 neoplasms/mice, respectively). The results suggest that peptides from common bean cv. Azufrado Higuera could prevent colitis-associated colon carcinogenesis. 相似文献
39.
Journal of Soils and Sediments - We conducted this investigation in order to develop a simple method for the determination of bioavailable vanadium and its speciation within sediments. The... 相似文献
40.
Suppavorasatit I De Mejia EG Cadwallader KR 《Journal of agricultural and food chemistry》2011,59(21):11621-11628
The effects of enzymatic deamidation by protein-glutaminase (PG) on the functional properties of soy protein isolate (SPI) were studied. Conditions for the deamidation were evaluated by means of response surface methodology (RSM). Optimal conditions based on achieving a high degree of deamidation (DD) with a concurrently low degree of hydrolysis (DH) were 44 °C, enzyme:substrate ratio (E/S) of 40 U/g protein and pH 7.0. Under optimal conditions, both DD and DH increased over time. SDS-PAGE results indicated that lower molecular mass subunits were produced with increasing DD. Far-UV circular dichroism spectra revealed that the α-helix structure decreased with higher DD, while the β-sheet structure increased until 15 min of deamidation (32.9% DD), but then decreased at higher DD. The solubility of deamidated SPI was enhanced under both acidic and neutral conditions. SPI with higher DD showed better emulsifying properties and greater foaming capacity than SPI, while foaming stability was decreased. It is possible to modify and potentially improve the functional properties of SPI by enzymatic deamidation using PG. 相似文献