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111.
Decolourisation and detoxification in the fungal treatment of textile wastewaters from dyeing processes 总被引:1,自引:0,他引:1
In this study a selected fungal strain, Bjerkandera adusta (Willdenow) P. Karsten MUT 3060, was tested in different culture conditions to assess its real potential for bioremediation of textile wastewaters in terms of both decolourisation and detoxification. The fungus efficiently decolourised (colour removal up to 96%) four simulated wastewaters that mimic the recalcitrance of real ones for pH values, concentration of dyes, additives and salts. In the culture condition with the lowest N content, the decolourisation was coupled with an important detoxification of two simulated effluents, underlining the important influence of the cultural medium composition not only on the degradation but also on the detoxification of industrial wastes. In the other cases, despite an extensive decolourisation, no detoxification was observed. The fungus was further tested against a real effluent, collected from a wastewater treatment plant before and after the tertiary treatment (ozonation) to compare the two technologies in terms of chemical and toxicological parameters. The fungal treatment, although less efficient than ozonation, caused a good decolourisation of the effluent, with colour values within the threshold limits of the Italian law; both the fungal and the ozone treatment caused a detoxification, but only towards one of the three organisms used for the ecotoxicological tests. These results underline the crucial importance of the ecotoxicological analysis in assessing the applicability of a wastewater treatment. 相似文献
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114.
Susanne Åkesson Phil W. Atkinson Ana Bermejo Javier de la Puente Mauro Ferri Chris M. Hewson Jan Holmgren Erich Kaiser Lyndon Kearsley Raymond H. G. Klaassen Heikki Kolunen Gittan Matsson Fausto Minelli Gabriel Norevik Hannu Pietiäinen Navinder J. Singh Fernando Spina Lukas Viktora Anders Hedenström 《Evolution; international journal of organic evolution》2020,74(10):2377-2391
Spectacular long-distance migration has evolved repeatedly in animals enabling exploration of resources separated in time and space. In birds, these patterns are largely driven by seasonality, cost of migration, and asymmetries in competition leading most often to leapfrog migration, where northern breeding populations winter furthest to the south. Here, we show that the highly aerial common swift Apus apus, spending the nonbreeding period on the wing, instead exhibits a rarely found chain migration pattern, where the most southern breeding populations in Europe migrate to wintering areas furthest to the south in Africa, whereas the northern populations winter to the north. The swifts concentrated in three major areas in sub-Saharan Africa during the nonbreeding period, with substantial overlap of nearby breeding populations. We found that the southern breeding swifts were larger, raised more young, and arrived to the wintering areas with higher seasonal variation in greenness (Normalized Difference Vegetation Index) earlier than the northern breeding swifts. This unusual chain migration pattern in common swifts is largely driven by differential annual timing and we suggest it evolves by prior occupancy and dominance by size in the breeding quarters and by prior occupancy combined with diffuse competition in the winter. 相似文献
115.
Virgilio Giannone Chiara Longo Arcangelo Damigella Domenico Raspagliesi Alfio Spina Massimo Palumbo 《Journal of industrial microbiology & biotechnology》2010,37(4):371-379
Properties of 13 Saccharomyces cerevisiae strains isolated from different sources (traditional sourdoughs, industrial baking yeasts etc.) were studied in dough produced
with durum wheat (Sicilian semolina, variety Mongibello). Durum wheat semolina and durum wheat flour are products prepared
from grain of durum wheat (Triticum durum Desf.) by grinding or milling processes in which the bran and germ are essentially
removed and the remainder is comminuted to a suitable degree of fineness. Acidification and leavening properties of the dough
were evaluated. Strains isolated from traditional sourdoughs (DSM PST18864, DSM PST18865 and DSM PST18866) showed higher leavening
power, valuable after the first and second hours of fermentation, than commercial baking yeasts. In particular the strain
DSM PST 18865 has also been successfully tested in bakery companies for the improvement of production processes. Baking and
staling tests were carried out on five yeast strains to evaluate their fermentation ability directly and their resistance
to the staling process. Amplified fragment length polymorphism (fAFLP) was used to investigate genetic variations in the yeast
strains. This study showed an appreciable biodiversity in the microbial populations of both wild and commercial yeast strains. 相似文献
116.
A Spina A Di Donato G Colella G Illiano 《Biochemical and biophysical research communications》1987,142(2):527-535
The activity of the adenylate cyclase catalytic subunit is higher in Harvey and Kirsten Murine Sarcoma Viruses-infected thyroid epithelial cells than in uninfected control cells either in the presence of Mg2+ alone or following stimulation by Mn2+ or forskolin. The higher activity is associated with an increased cAMP cellular content. The Gpp(NH)p and F- anion are more effective positive modulators in the control than in the virus infected cells: these results exclude therefore that the ras p21 proteins can act as the G-protein alpha-subunit and suggest that they negatively interfere with the G-protein modulation of the adenylate cyclase system. 相似文献
117.
Marco Fedele Elena Faggiano Luca Dedè Alfio Quarteroni 《Biomechanics and modeling in mechanobiology》2017,16(5):1779-1803
In this paper, we propose a full computational framework to simulate the hemodynamics in the aorta including the valve. Closed and open valve surfaces, as well as the lumen aorta, are reconstructed directly from medical images using new ad hoc algorithms, allowing a patient-specific simulation. The fluid dynamics problem that accounts from the movement of the valve is solved by a new 3D–0D fluid–structure interaction model in which the valve surface is implicitly represented through level set functions, yielding, in the Navier–Stokes equations, a resistive penalization term enforcing the blood to adhere to the valve leaflets. The dynamics of the valve between its closed and open position is modeled using a reduced geometric 0D model. At the discrete level, a finite element formulation is used and the SUPG stabilization is extended to include the resistive term in the Navier–Stokes equations. Then, after time discretization, the 3D fluid and 0D valve models are coupled through a staggered approach. This computational framework, applied to a patient-specific geometry and data, allows to simulate the movement of the valve, the sharp pressure jump occurring across the leaflets, and the blood flow pattern inside the aorta. 相似文献
118.
Chera L Maarouf Ian D Daugs Salvatore Spina Ruben Vidal Tyler A Kokjohn RLyle Patton Walter M Kalback Dean C Luehrs Douglas G Walker Eduardo M Castaño Thomas G Beach Bernardino Ghetti Alex E Roher 《Molecular neurodegeneration》2008,3(1):1-18
Background
Mutations in the presenilin (PSEN) genes are associated with early-onset familial Alzheimer's disease (FAD). Biochemical characterizations and comparisons have revealed that many PSEN mutations alter γ-secretase activity to promote accumulation of toxic Aβ42 peptides. In this study, we compared the histopathologic and biochemical profiles of ten FAD cases expressing independent PSEN mutations and determined the degradation patterns of amyloid-β precursor protein (AβPP), Notch, N-cadherin and Erb-B4 by γ-secretase. In addition, the levels of Aβ40/42 peptides were quantified by ELISA.Results
We observed a wide variation in type, number and distribution of amyloid deposits and neurofibrillary tangles. Four of the ten cases examined exhibited a substantial enrichment in the relative proportions of Aβ40 over Aβ42. The AβPP N-terminal and C-terminal fragments and Tau species, assessed by Western blots and scanning densitometry, also demonstrated a wide variation. The Notch-1 intracellular domain was negligible by Western blotting in seven PSEN cases. There was significant N-cadherin and Erb-B4 peptide heterogeneity among the different PSEN mutations.Conclusion
These observations imply that missense mutations in PSEN genes can alter a range of key γ-secretase activities to produce an array of subtly different biochemical, neuropathological and clinical manifestations. Beyond the broad common features of dementia, plaques and tangles, the various PSEN mutations resulted in a wide heterogeneity and complexity and differed from sporadic AD. 相似文献119.
Ecological conditions during winter predict arrival date at the breeding quarters in a trans-Saharan migratory bird 总被引:7,自引:0,他引:7
Nicola Saino Tibor Szép Maria Romano Diego Rubolini Fernando Spina Anders Pape Møller 《Ecology letters》2004,7(1):21-25
We studied variation in arrival date to the breeding colonies in Italy of a trans‐Saharan migratory bird, the barn swallow Hirundo rustica, in relation to variation in ecological conditions, as reflected by the normalized difference vegetation index (NDVI), in the winter quarters. Arrival date of old but not young individuals captured during consecutive breeding seasons was earlier after winters with favourable conditions. Change in arrival date in relation to change in NDVI was similar in the two sexes. Change in arrival date significantly and positively predicted change in breeding date. As a result of increased frequency of second broods determined by earlier arrival, the number of fledged offspring per season was larger after African winters with good in comparison to poor ecological conditions for barn swallows. This is the first study demonstrating phenotypic plasticity in migration phenology of a long‐distance migratory bird in relation to ecological conditions during wintering. 相似文献
120.
Soraia A. C. Jorge Alexandra S. Santos Ângela Spina Carlos A. Pereira 《Cytotechnology》2008,57(1):51-59
Drosophila melanogaster S2 cells were transfected with a plasmid vector (pAcHBsAgHy) containing the S gene, coding for the hepatitis B virus surface
antigen (HBsAg), under control of the constitutive drosophila actin promoter (pAc), and the hygromycin B (Hy) selection gene.
The vector was introduced into Schneider 2 (S2) Drosophila cells by DNA transfection and a cell population (S2AcHBsAgHy) was
selected by its resistance to hygromycin B. The pAcHBsAgHy vector integrated in transfected S2 cell genome and approximately
1,000 copies per cell were found in a higher HBsAg producer cell subpopulation. The HBsAg production varied in different subpopulations,
but did not when a given subpopulation was cultivated in different culture flasks. Higher HBsAg expression was found in S2AcHBsAgHy
cells cultivated in Insect Xpress medium (13.5 μg/1E7 cells) and SFX medium (7 μg/1E7 cells) in comparison to SF900II medium
(0.6 μg/1E7 cells). An increase of HBsAg was observed in culture maintained under hygromycin selection pressure. Data presented
in the paper show that S2AcHBsAgHy cells produce efficiently the HBsAg which is mainly found in the cell supernatant, suggesting
that HBsAg is secreted from the cells. The data also show that our approach using the Drosophila expression system is suitable
for the preparation of other viral protein preparation. 相似文献