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61.
62.
M. Beccari L. Bertin D. Dionisi F. Fava S. Lampis M. Majone F. Valentino G. Vallini M. Villano 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(6):901-908
BACKGROUND: The performance of a three‐stage process for polyhydroxyalkanoate (PHA) bioproduction from olive oil mill effluents (OME) has been investigated. In the first anaerobic stage OME were fermented in a packed bed biofilm reactor into volatile fatty acids (VFAs). This VFA‐rich effluent was fed to the second stage, operated in an aerobic sequencing batch reactor (SBR), to enrich mixed cultures able to store PHAs. Finally, the storage response of the selected consortia was exploited in the third aerobic stage, operated in batch conditions. RESULTS: The anaerobic stage increased the VFA percentage in the OME from 18% to ~32% of the overall chemical oxygen demand (COD). A biomass with high storage response was successfully enriched in the SBR fed with the fermented OME at an organic load rate of 8.5 gCOD L?1 d?1, with maximum storage rate and yield (146 mgCOD gCOD?1 h?1 and 0.36 COD COD?1, respectively) very similar to those obtained with a synthetic VFA mixture. By means of denaturing gradient gel electrophoresis (DGGE) analysis, different bacterial strains were identified during the two SBR runs: Lampropedia hyalina and Candidatus Meganema perideroedes, with the synthetic feed or the fermented OMEs, respectively. In the third stage, operated at increasing loads, the maximum concentration of the PHA produced increased linearly with the substrate fed. Moreover, about half of the stored PHAs were produced from substrates other than VFAs, mostly alcohols. CONCLUSION: The results obtained indicate that the process is effective for simultaneous treatment of OME and their valorization as a renewable resource for PHA production. Copyright © 2009 Society of Chemical Industry 相似文献
63.
In the last few years, there has been a renewed interest in the molten salt reactor (MSR), one of the “Generation IV International Forum” concepts, which adopts a circulating molten salt mixture as both heat generator (fuel) and coolant. The heat transfer of a fluid with internal heat generation depends on the strength of the source whose influence on the heat exchange process is significant enough to demand consideration. At present, few studies have been performed on the subject from either an experimental or a numerical point of view.This study considers fluids with a wide range of Reynolds numbers, flowing through smooth and straight circular tubes within which the flow is hydrodynamically developed but thermally developing (conditions of interest for MSR core channels). The study aims at an assessment of the heat transfer modelling for a large variety of fluids (with Prandtl numbers in the range 0≤Pr≤104), in particular taking into account the influence of the internal heat generation on the temperature distribution, which plays an important role in the case of molten salts for nuclear reactors. To this purpose, the general and unified solution of the heat transfer equation is applied to the turbulent Graetz problem with boundary conditions of the third kind and arbitrary heat source distribution, incorporating recent formulations for turbulent flow and convection.Computed results are shown to be in a good agreement with experimental data concerning heat transfer evaluations for both fully developed and thermally developing flow conditions, over a large range of Prandtl numbers (10?2<Pr<104). Finally, a preliminary correlation, which includes the Prandtl number range of interest for molten salts, is proposed for the Nusselt number predictions in the case of simultaneous uniform wall heat flux and internal heat generation. 相似文献
64.
Valentino Kristin; Cicchetti Dante; Toth Sheree L.; Rogosch Fred A. 《Canadian Metallurgical Quarterly》2006,42(3):474
Mother-child play of 12-month-old infants (N = 130) from maltreating (N = 78) and nonmaltreating (N = 52) families was analyzed as a context that integrates infants' developing social and cognitive skills. Play was coded from semistructured and unstructured play paradigms. No group differences were found in infants' play maturity. Infants from abusing families demonstrated more imitative play than infants from nonmaltreating families, and engaged in less independent play than infants from both neglecting and nonmaltreating families, suggesting a delay in emerging social behaviors. Mothers from abusing and nonmaltreating families differed in attention directing behaviors. Maternal behaviors predicted child play style variables, but did not mediate the effects of maltreatment. Findings discuss the influence of an early maltreating environment upon the development of the emergent self. Implications for early intervention are underscored. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
Valentino Giacomuzzi Luca Cappellin Iuliia Khomenko Franco Biasioli Stefan Schütz Marco Tasin Alan L. Knight Sergio Angeli 《Journal of chemical ecology》2016,42(12):1265-1280
This study investigated the volatile emission from apple (Malus x domestica Borkh., cv. Golden Delicious) foliage that was either intact, mechanically-damaged, or exposed to larval feeding by Pandemis heparana (Denis and Schiffermüller) (Lepidoptera: Tortricidae). Volatiles were collected by closed-loop-stripping-analysis and characterized by gas chromatography-mass spectrometry in three time periods: after 1 h and again 24 and 48 h later. Volatiles for all treatments also were monitored continuously over a 72-h period by the use of proton transfer reaction – time of flight-mass spectrometry (PTR-ToF-MS). In addition, the volatile samples were analyzed by gas chromatography-electroantennographic detection (GC-EAD) using male and female antennae of P. heparana. Twelve compounds were detected from intact foliage compared with 23 from mechanically-damaged, and 30 from P. heparana-infested foliage. Interestingly, six compounds were released only by P. heparana-infested foliage. The emission dynamics of many compounds measured by PTR-ToF-MS showed striking differences according to the timing of herbivory and the circadian cycle. For example, the emission of green leaf volatiles began shortly after the start of herbivory, and increased over time independently from the light-dark cycle. Conversely, the emission of terpenes and aromatic compounds showed a several-hour delay in response to herbivory, and followed a diurnal rhythm. Methanol was the only identified volatile showing a nocturnal rhythm. Consistent GC-EAD responses were found for sixteen compounds, including five aromatic ones. A field trial in Sweden demonstrated that benzyl alcohol, 2-phenylethanol, phenylacetonitrile, and indole lures placed in traps were not attractive to Pandemis spp. adults, but 2-phenylethanol and phenylacetonitrile when used in combination with acetic acid were attractive to both sexes. 相似文献
66.
Valentina Picchi Carmela Migliori Roberto Lo Scalzo Gabriele Campanelli Valentino Ferrari Luigi Francesco Di Cesare 《Food chemistry》2012,130(3):501-509
An experiment was conducted that compared the phytochemical content of two genotypes (Emeraude and Magnifico) of a green typology cauliflower under conventional or organic management. In addition, three fertilisation regimes were considered within the framework of organic agriculture. The two genotypes showed a contrasting response to organic practices: the phytochemical content of Emeraude was generally reduced, while in Magnifico, most of the quality parameters were unaffected or increased. In addition, under organic management, the use of higher fertilisation levels significantly increased the phytochemical production of Magnifico, in particular ascorbic acid (P < 0.05) and polyphenols (P < 0.01). However, the same fertigation treatments decreased the phytochemical production of Emeraude, particularly glucosinolates and ascorbic acid. This genotype was identified as a key factor in the determination of cauliflower quality under different management practices. Moreover, our results indicate that the addition of fertilisers to organic soil might be effective only with a cauliflower genotype suited to organic agriculture. 相似文献
67.
68.
Corticotropin-releasing factor (CRF), the neurohormone that initiates the endocrine limb of the stress response via its actions on the anterior pituitary, also acts as a neurotransmitter in the noradrenergic locus coeruleus (LC) to activate this system during stress. Because the central nucleus of the amygdala contains numerous CRF-immunoreactive neurones, the present study examined whether CRF projections from the central nucleus of the amygdala target LC dendrites, thereby providing a mechanism for limbic-CRF modulation of brain noradrenergic activity. Retrograde tracers injected into the rostrolateral pericoerulear region, where CRF-immunoreactive fibres are dense, labelled numerous CRF-immunoreactive neurones in the central nucleus of the amygdala. Consistent with this, ultrastructural analysis of the rostrolateral pericoerulear region in sections that were dually labelled for an anterograde tracer (biotinylated dextran amine, BDA) injected into the central nucleus of the amygdala and CRF immunoreactivity revealed that a substantial percentage (35%) of amygdaloid axon terminals were CRF-immunoreactive. These terminals formed synaptic specializations with unlabelled dendrites that were more often of the asymmetric (excitatory) type. Additionally, ultrastructural analysis of sections that were dually labelled to visualize CRF-and tyrosine hydroxlase-immunoreactivity demonstrated synaptic specializations between CRF-immunoreactive terminals and LC dendrites in the rostrolateral peri-LC, which were also frequently asymmetric. Taken together with previous ultrastructural findings that LC dendrites in the rostrolateral pericoerulear region are targeted by anterogradely labelled terminals from the central nucleus of the amygdala, the present results implicate this nucleus as a source of CRF that can impact on LC activity via effects on dendrites in the rostrolateral pericoerulear region. This cellular substrate for amygdaloid-CRF modulation of brain noradrenergic activity may serve as a mechanism for the integration of emotional and cognitive responses to stress. 相似文献
69.
J Primo P Geelen J Brugada A Lorga Filho L Mont F Wellens M Valentino P Brugada 《Canadian Metallurgical Quarterly》1998,17(10):783-787
1. Despite the frenetic pace of cytochrome P450 (CYP) research, important questions remain about the possible role of xenobiotic-metabolizing CYP in development and cellular homeostasis. 2. The recent experimental development of CYP null mouse lines has provided valuable new models for addressing these issues, as well as providing novel in vivo models to study the precise role of CYP in chemical-mediated toxicity. 3. The present review summarizes results from the three Cyp gene knockout mouse lines generated so far and looks at likely future directions of this research field. 4. Also discussed are null mouse lines with targeted mutations in genes encoding receptors having primary roles in Cyp gene regulation. 相似文献
70.
Laura Piccagli Dr. Enrica Fabbri Dr. Monica Borgatti Dr. Nicoletta Bianchi Dr. Valentino Bezzerri Dr. Irene Mancini Dr. Elena Nicolis Dr. Cristina M. Dechecchi Dr. Ilaria Lampronti Dr. Giulio Cabrini Prof. Roberto Gambari Prof. 《ChemMedChem》2009,4(12):2024-2033
Virtual screening against NF‐κB p50 using docking simulations was applied by starting from a three‐dimensional (3D) database containing more than 4.6 million commercially available structures. This database was filtered by specifying a subset of commercially available compounds sharing a (2E,Z)‐3‐(2‐hydroxyphenyl)‐2‐propenoate substructure and relevant druglike properties. Docking to p50 NF‐κB was performed with a test set of six known inhibitors of NF‐κB–DNA interactions. In agreement with docking results, the highest‐scored compound displayed a high level of inhibitory activity in electrophoretic mobility shift assay (EMSA) experiments (inhibition of NF‐κB–DNA interactions) and on biological functions dependent on NF‐κB activity (inhibition of IL‐8 gene expression in cystic fibrosis IB3‐1 cells). We found that this in silico screening approach is suitable for the identification of low‐molecular‐weight compounds that inhibit NF‐κB–DNA interactions and NF‐κB‐dependent functions. Information deduced from the discovery of the new lead compound and its binding mode could result in further lead optimization resulting in more potent NF‐κB inhibitors. 相似文献