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Rosalba Lanciotti Francesca Patrignani Luciana Iucci Maria Elisabetta Guerzoni Giovanna Suzzi Nicoletta Belletti Fausto Gardini 《Food chemistry》2007,104(2):693-701
The aim of this work was to evaluate the biogenic amine (BA) content during the ripening of both bovine and ovine cheeses obtained using milk subjected to a homogenization treatment at 100 MPa before cheese-making. The data obtained were compared with those from cheeses produced by the same milks without any treatment or thermized. The results showed that both microbial ecology and BA concentrations of cheeses during ripening were significantly influenced by the type of milk used for cheese-making and by the treatment applied to the raw materials. In particular, the microbial counts found in Caciotta indicated that the high pressure homogenization (HPH) of milk significantly reduced the presence of the yeasts, Micrococcaceae and lactobacilli at the end of ripening. On the other hand, the HPH treatment of milk favoured the proliferation of yeasts in ovine cheese. Moreover, the ovine cheeses were characterized by a remarkably higher accumulation of BA than bovine cheeses. However, the HPH treatment of milk was able to drastically reduce the biogenic amine concentrations in both cheese typologies at the end of ripening. 相似文献
53.
Natale Francesco; Antinucci Francesco; Spinozzi Giovanna; Potí Patrizia 《Canadian Metallurgical Quarterly》1986,100(4):335
Several investigators have reported the achievement of Stage 6 object concept in a number of species of nonhuman primates. Because Stage 6 object concept implies a capacity for mental representation, such an achievement would demonstrate the presence of a crucial capacity in nonhuman primate cognition. There are, it is suggested, problems in the way nonhuman primates have been tested for Stage 6 object concept (i.e., that the tasks employed could be solved in nonrepresentational ways). The present study attempted to differentiate between representational and nonrepresentational responses in the typical task used for testing Stage 6 object concept (following the invisible displacements of an object). The performance of 2 22-mo-old Ss, a Japanese macaque and a gorilla, was compared. It was found that only the gorilla solved the task with the use of mental representation. The macaque consistently tried to solve the task by employing practical, nonrepresentational strategies. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The effect of mechanical recycling on the microstructure and properties of PA66 composites reinforced with carbon fibers 下载免费PDF全文
Giovanna Colucci Oxana Ostrovskaya Alberto Frache Brunetto Martorana Claudio Badini 《应用聚合物科学杂志》2015,132(29)
This article aims to prepare by injection molding recycled polymeric composites based on PA66 reinforced with short carbon fibers after artificial aging for applications in the automotive field. The aging cycles involves the combined action of UV radiation, moisture, and temperature in order to simulate the common outdoor conditions. The 100% recycled composites are obtained by the regranulation of the aged specimens followed by the remelting and re‐injection molding. The study is focused on the comparison between the mechanical behavior and the microstructure of the composites before and after mechanical recycling. The results of mechanical, thermal, and morphological investigations reveal that the recycling process had no significant effect on the final properties and microstructure of the recycled composites. Therefore the recycled PA66CF30 composites could be successfully used for structural or semi‐structural automotive applications guaranteeing good final performances and advantages from the environmental point of view. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42275. 相似文献
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Giovanna Calabrese Raffaella Giuffrida Debora Lo Furno Nunziatina Laura Parrinello Stefano Forte Rosario Gulino Cristina Colarossi Luciana Rita Schinocca Rosario Giuffrida Venera Cardile Lorenzo Memeo 《International journal of molecular sciences》2015,16(7):15609-15624
The Low-Affinity Nerve Growth Factor Receptor (LNGFR), also known as CD271, is a member of the tumor necrosis factor receptor superfamily. The CD271 cell surface marker defines a subset of multipotential mesenchymal stromal cells and may be used to isolate and enrich cells derived from bone marrow aspirate. In this study, we compare the proliferative and differentiation potentials of CD271+ and CD271− mesenchymal stromal cells. Mesenchymal stromal cells were isolated from bone marrow aspirate and adipose tissue by plastic adherence and positive selection. The proliferation and differentiation potentials of CD271+ and CD271− mesenchymal stromal cells were assessed by inducing osteogenic, adipogenic and chondrogenic in vitro differentiation. Compared to CD271+, CD271− mesenchymal stromal cells showed a lower proliferation rate and a decreased ability to give rise to osteocytes, adipocytes and chondrocytes. Furthermore, we observed that CD271+ mesenchymal stromal cells isolated from adipose tissue displayed a higher efficiency of proliferation and trilineage differentiation compared to CD271+ mesenchymal stromal cells isolated from bone marrow samples, although the CD271 expression levels were comparable. In conclusion, these data show that both the presence of CD271 antigen and the source of mesenchymal stromal cells represent important factors in determining the ability of the cells to proliferate and differentiate. 相似文献
56.
Irene Vanni Simona Coco Anna Truini Marta Rusmini Maria Giovanna Dal Bello Angela Alama Barbara Banelli Marco Mora Erika Rijavec Giulia Barletta Carlo Genova Federica Biello Claudia Maggioni Francesco Grossi 《International journal of molecular sciences》2015,16(12):28765-28782
Next-generation sequencing (NGS) is a cost-effective technology capable of screening several genes simultaneously; however, its application in a clinical context requires an established workflow to acquire reliable sequencing results. Here, we report an optimized NGS workflow analyzing 22 lung cancer-related genes to sequence critical samples such as DNA from formalin-fixed paraffin-embedded (FFPE) blocks and circulating free DNA (cfDNA). Snap frozen and matched FFPE gDNA from 12 non-small cell lung cancer (NSCLC) patients, whose gDNA fragmentation status was previously evaluated using a multiplex PCR-based quality control, were successfully sequenced with Ion Torrent PGM™. The robust bioinformatic pipeline allowed us to correctly call both Single Nucleotide Variants (SNVs) and indels with a detection limit of 5%, achieving 100% specificity and 96% sensitivity. This workflow was also validated in 13 FFPE NSCLC biopsies. Furthermore, a specific protocol for low input gDNA capable of producing good sequencing data with high coverage, high uniformity, and a low error rate was also optimized. In conclusion, we demonstrate the feasibility of obtaining gDNA from FFPE samples suitable for NGS by performing appropriate quality controls. The optimized workflow, capable of screening low input gDNA, highlights NGS as a potential tool in the detection, disease monitoring, and treatment of NSCLC. 相似文献
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Condensed tannin accumulation and nitrogen fixation potential of Onobrychis viciifolia Scop. grown in a Mediterranean environment 下载免费PDF全文
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Gianpiero Pataro Beatrice SenatoreGiorgio Donsì Giovanna Ferrari 《Journal of food engineering》2011,105(1):79-88
The effects of both the electric and flow parameters on the lethality and energy efficiency of a pulsed electric fields (PEF) treatment were studied. An experimental plan was designed in order to study the microbial inactivation of Saccharomyces cerevisiae and Escherichia coli cells inoculated in a buffer solution. The following process parameters were taken into consideration: electric field strength (13-30 kV/cm), total specific energy input (20-110 J/mL), flow rate of the processed stream (1-4 L/h) and number of passes through the chamber (up to 5).The results showed that, at a fixed flow rate (2 L/h), microbial inactivation of both microbial strains increased with increasing field strength and applied energy input. The maximum inactivation level (5.9 Log-cycles for S. cerevisiae and 7.0 Log-cycles for E. coli) corresponded to the more intensive PEF treatment (30 kV/cm and 110 J/mL). However, for any given field strength applied, the inactivation rate decreased by increasing the energy input. This behavior was attributed to the presence of heterogeneous treatment conditions due, for example, to a different morphology (size and shape) or cell membrane (composition, structure), a local variation of the electric field strength in the treatment chamber, the tendency of microbial cells to form clusters, or a non-uniform distribution of the residence time of the product in the PEF chamber.A more effective stirring of the microbial suspensions which was achieved, at a fixed field strength (18 kV/cm), either by increasing the flow rate with a single pass operation through the PEF chamber, or by operating in re-circulating mode at a constant flow rate, provided a significant increase in the effectiveness and energy efficiency of the pulse treatment.A mathematical model based on the Weibull distribution adequately described the inactivation kinetics of both microbial strains under different flow dynamic conditions. 相似文献