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101.
Prof. Roberta Marchetti Ferran Nieto Fabregat Dr. Mateusz Pallach Dr. Djamel Gully Dr. Eric Giraud Prof. Antonio Molinaro Dr. Katarzyna A. Duda Alba Silipo 《Chembiochem : a European journal of chemical biology》2021,22(1):147-150
Acetobacter pasteurianus, a member of the Alphaproteobacteria, is an acetic acid-producing bacterium present on sugar-rich substrates such as such as fruits, flowers and vegetables and traditionally used in the production of fermented food. The preferred living habitat associated with acid conditions makes the structure of the bacterial cell wall interesting to study, due to expected uncommon features. We have used a combination of chemical, analytical and NMR spectroscopy approaches to define the complete structure of the core oligosaccharide from A. pasteurianus CIP103108 LPS. Interestingly, the core oligosaccharide displays a high concentration of negatively charged groups, structural features that might contribute to reinforcing the bacterial membrane. 相似文献
102.
Danilo Marimpietri Irma Airoldi Angelo Corso Faini Fabio Malavasi Fabio Morandi 《International journal of molecular sciences》2021,22(8)
The long-underestimated role of extracellular vesicles in cancer is now reconsidered worldwide by basic and clinical scientists, who recently highlighted novel and crucial activities of these moieties. Extracellular vesicles are now considered as king transporters of specific cargoes, including molecular components of parent cells, thus mediating a wide variety of cellular activities both in normal and neoplastic tissues. Here, we discuss the multifunctional activities and underlying mechanisms of extracellular vesicles in neuroblastoma, the most frequent common extra-cranial tumor in childhood. The ability of extracellular vesicles to cross-talk with different cells in the tumor microenvironment and to modulate an anti-tumor immune response, tumorigenesis, tumor growth, metastasis and drug resistance will be pinpointed in detail. The results obtained on the role of extracellular vesicles may represent a panel of suggestions potentially useful in practice, due to their involvement in the response to chemotherapy, and, moreover, their ability to predict resistance to standard therapies—all issues of clinical relevance. 相似文献
103.
A. Serraino N. Arrigoni F. Ostanello M. Ricchi G. Marchetti P. Bonilauri E. Bonfante F. Giacometti 《Journal of dairy science》2014
Mycobacterium avium ssp. paratuberculosis (MAP) is the etiological agent of paratuberculosis, a chronic contagious bacterial disease primarily affecting dairy cattle. Paratuberculosis represents a dual problem for the milk production chain: in addition to economic losses to affected herds, MAP may have zoonotic potential. Infected herds must be identified in order to implement programs designed to reduce the incidence of disease within and between herds and to prevent MAP from entering the food chain. The objective of this study was to evaluate the sensitivity and specificity of a screening sampling plan (SSP) to detect MAP-positive dairy herds by repetitive analysis of bulk tank milk (BTM) samples by ELISA and in-line milk filter (ILMF) samples by PCR. Samples from BTM and ILMF were collected twice from 569 dairy herds in southern Italy. Additionally, 12,016 individual milk samples were collected: 9,509 from 102 SSP-positive herds (SSP MAP-positive) and 2,507 from 21 randomly selected SSP-negative herds (SSP MAP-negative). There was a total of 126 SSP MAP-positive herds (i.e., 21.3% SSP MAP-positive herds; 95% confidence interval = 18.0–24.9); the within-herd apparent prevalence (AP) ranged between 0.00 and 22.73% (mean 6.07%). A significant difference in within-herd AP was shown between SSP MAP-positive herds and SSP MAP-negative herds. A highly significant association was shown between the median AP herd status (>5%) and positivity to at least one ILMF or BTM sample. The SSP detected a minimum of 56.25% of low AP herds (AP ≤2.0%) up to a maximum of 100% of herds with a within-herd AP ≥8.0%. Overall, the SSP detected 85.57% of herds in which at least one individual milk sample was positive by ELISA. The proposed SSP was an inexpensive and useful tool to detect MAP-positive herds with a higher risk of infection diffusion and milk contamination. Although the SSP cannot be used for MAP-free certification of herds, it could be useful to prioritize appropriate control measures aimed at reducing the prevalence of infection in dairy herds and milk contamination. 相似文献
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105.
Within a warehouse, the picking activity often relies on human operators. Therefore, when designing and evaluating a manual picking system, it is important to consider that, besides the high flexibility the pickers are able to warrant, they inevitably require an additional effort due to their ergonomic working conditions. In this paper, the authors propose a new model to consider such additional effort, starting from the concepts of human availability and rest allowance. The new method allows the evaluation of the current configuration of a certain warehouse, considering two different operative situations (directly employed operators and indirectly employed ones). Moreover, it makes it possible to estimate and to understand the benefits that can be achieved by introducing some ergonomic improvements. The proposed procedure has also been applied to a real industrial case study. 相似文献
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107.
Jony Javorski Eckert Ludmila Corrêa de Alkmin e Silva Fabio Mazzariol Santiciolli Eduardo dos Santos Costa Fernanda Cristina Corrêa Franco Giuseppe Dedini 《国际能源研究杂志》2018,42(11):3506-3523
Two big issues involving electric vehicles are energy supply and power management control. To deal with the energy supply problem, this paper proposes the application of a hybrid energy source system, composed of battery pack and ultracapacitor bank. The power management control between the energy supplies was defined by a fuzzy logic with inference rules optimized through genetic algorithm. The genetic algorithm optimizes lower and upper limits of membership functions aiming to reduce the hybrid energy source system total mass while maximizing the electric vehicle drive range and performance. Through the Pareto frontier, we found the best trade‐off solution. 相似文献
108.
Ciro Vasmara Massimo Pindo Diego Micheletti Rosa Marchetti 《International Journal of Hydrogen Energy》2018,43(18):8707-8717
This study addresses for the first time the influence of initial pH on the evolution of microbial consortia in dark fermentation of scotta permeate, using a high-throughput sequencing approach. Three fermentation phases could be detected: 1) a lag phase with no substantial differences in microbial composition at different initial pH values; 2) an exponential H2 production phase, accompanied by a general increase of Clostridium genus components and higher incidence of Trichococcus genus at neutral and alkaline pH; 3) a final stationary phase, characterized by a general increase of Bifidobacterium and Lactobacillus genera in all reactors. The initial pH value influenced the relative abundance of Trichococcus at 16–48 h of incubation. The metabolic activity of this genus increased the amount of metabolic precursors of H2 so that, when pH lowered to 5.4, clostridia in the reactors with initial alkaline pH become more active H2-producers than those in the others. 相似文献
109.
110.
Esti Marco Liburdi Katia Palumbo Fabio Benucci Ilaria Garzillo Anna Maria Vittoria 《Food science and biotechnology》2014,23(1):151-155
The catalytic activity of a lysozyme-based oenological preparation toward the specific substrates i) glycol chitosan, as a non-cellular synthetic substrate, and ii) Oenococcus oeni, as a microbial substrate for muramidase activity, was investigated in wine-like acidic medium (tartaric buffer, pH 3.2). The good reproducibility and reliability of results revealed that both substrates are useful for lysozyme kinetics studies. Both the chitinolytic and muramidase activity of lysozyme were affected by uncompetitive substrate inhibition. However, the O. oeni effect occurred at very high concentration with respect to the typical wine bacterial content, even when microbial population reaches its maximum growth level during malolactic fermentation. The optimum pH and temperature for lysozyme activity were very far from the usual wine handling conditions, but residual enzyme activity was observed at pH 3.2 and 20°C, confirming that the oenological application of lysozyme is a useful practice. 相似文献