1,272 research outputs found
Dynamical Criticality in Gene Regulatory Networks
A well-known hypothesis, with far-reaching implications, is that biological evolution should preferentially lead to states that are dynamically critical. In previous papers, we showed that a well-known model of genetic regulatory networks, namely, that of random Boolean networks, allows one to study in depth the relationship between the dynamical regime of a living being's gene network and its response to permanent perturbations. In this paper, we analyze a huge set of new experimental data on single gene knockouts in S. cerevisiae, laying down a statistical framework to determine its dynamical regime. We find that the S. cerevisiae network appears to be slightly ordered, but close to the critical region. Since our analysis relies on dichotomizing continuous data, we carefully consider the issue of an optimal threshold choice
Autochthonous Lactobacillus paracasei subsp. paracasei strains isolated from Caciocavallo cheese: identification and in-vitro investigation on potential probiotic and functional properties
Background: In recent years consumers, due to the growing interest for functional foods, have put particularly a ention on prod- ucts enriched with probiotic lactic acid bacteria for their ability to give human bene t by their assumption. Microorganisms to be considered as probiotic should be able to survive to gastrointestinal juices and colonize the intestinal tract to provide bene ts to human health.
The aim of the study consisted on the in vitro investigation of novel LAB strains, isolated during cheesemaking and ripening of Caciocavallo cheese, and on their probiotic potential for food application.
Methods: In order to select potential probiotic bacteria, LAB isolates were preliminarily screened for their survival to simulated gastro-intestinal transitand assayed for others activities of probiotic and functional interest. Thanks to promising a itude as poten- tial probiotics, four strains were tested to evaluate their adhesion ability on Caco-2 cell lines used as intestinal cell model. Microbiological data were analysed by one-way analysis of variance (ANOVA). Comparisons of means were carried out using post-hoc Tukey’s test. For vitro adhesion experiments, statistical signi cance was evaluated by Kruskal-Wallis test for equal medi- ans.
Results: Twenty- ve LAB, presumptively identi ed as Lactobacillus spp., were isolated from cheese during 60 days of ripening and screened for their survival to simulated gastrointestinal transit. Sixteen isolates that showed a survival rate ≥85% were identi edas 10 di erent pro les of Lb. paracasei subsp. paracasei. The 10 strains tolerated high concentration of bile salts by Minimal Inhibitory Concentration and growth rate assays and showed susceptibility or moderate susceptibility against antibiotics of human and vet- erinary importance, except for the resistanceto the class of aminoglycoside antibiotics. Eight out 10 strains showed in vitro choles- terol-lowering ability, whereas all strains showed antioxidant activity of their cell-free supernatants. Moreover, the four strains with highest survival to simulated gastrointestinal transit showed the ability to adhere to Caco-2 cells.
Conclusion: The results suggest that some strains may be e ective probiotics to be use as tool to design probiotic dairy products after con rmation probiotic activities in further in vivo studies. Findings of the present study suggest that four strains showed good or strong adherent ability on Caco-2 cell monolayer, that is one of prerequisite that probiotic bacteria must have to perform their functional properties
Physical properties and antimicrobial activity of bioactive film based on whey protein and Lactobacillus curvatus 54M16 producer of bacteriocins
The objective of the work was to study the viability and antimicrobial activity of bacteriocin-producing lactic
acid bacteria (LAB) incorporated into whey protein/inulin/gelatine (WP) edible films in presence or absence of
nutrient (modified MRS broth). Moreover, the role of the cell on the film structure and properties has been
investigated. The results of the work showed that WP-based films were able to ensure a high viability of the
bacteriocin-producing strain L. curvatus 54M16 during 28 days of storage at 4 �C. The addition of nutrient in the
film matrix slightly affected the viability of the cells, but it was critical for the antimicrobial activity of the films.
Films in presence of nutrient showed a good antimicrobial activity against L. innocua C6 as in vitro system as on
cooked ham. The presence of LAB has a significant effect on the structure of the film: it reduced the viscosity of
the film forming solution and improved the elasticity and the percentage of elongation. Whereas, no effect was
observed for water vapour transmission rate and solubility. Thus, WP-based films in presence of modified MRS
broth can be used as effective delivery and carrier systems for lactic acid bacteria to develop bioactive edible film
or coating with antimicrobial properties
Physical properties and antimicrobial activity of bioactive film based on whey protein and Lactobacillus curvatus 54M16 producer of bacteriocins
The objective of the work was to study the viability and antimicrobial activity of bacteriocin-producing lactic acid bacteria (LAB) incorporated into whey protein/inulin/gelatine (WP) edible films in presence or absence of nutrient (modified MRS broth). Moreover, the role of the cell on the film structure and properties has been investigated. The results of the work showed that WP-based films were able to ensure a high viability of the bacteriocin-producing strain L. curvatus 54M16 during 28 days of storage at 4 °C. The addition of nutrient in the film matrix slightly affected the viability of the cells, but it was critical for the antimicrobial activity of the films. Films in presence of nutrient showed a good antimicrobial activity against L. innocua C6 as in vitro system as on cooked ham. The presence of LAB has a significant effect on the structure of the film: it reduced the viscosity of the film forming solution and improved the elasticity and the percentage of elongation. Whereas, no effect was observed for water vapour transmission rate and solubility. Thus, WP-based films in presence of modified MRS broth can be used as effective delivery and carrier systems for lactic acid bacteria to develop bioactive edible film or coating with antimicrobial properties
Energy consumption and analysis of industrial drying plants for fresh pasta process
The article presents results concerning the energy needs and the CO2 emissions resulting from the production process of a small factory (located in Molise region) producing fresh pasta. Two production processes are responsible for the most of energy demand. The pasteurisation and the drying processes are responsible for the 50% of the electricity consumption and the whole thermal energy. Therefore innovative solutions have been studied in order to limit the energy requirements and the CO2 emissions. Such solutions take into account the adoption of high-efficiency motors and heat recovery in the main processes
Analysis of pronuclear zygote configurations in 459 clinical pregnancies obtained with assisted reproductive technique procedures
BACKGROUND: Embryos selection is crucial to maintain high performance in terms of pregnancy rate, reducing the risk of multiple pregnancy during IVF. Pronuclear and nucleolar characteristics have been proposed as an indicator of embryo development and chromosomal complement in humans, providing information about embryo viability.
METHODS: To correlate the zygote-score with the maternal age and the outcome of pregnancy, we analyzed the pronuclear and nucleolar morphology, the polar body alignment and the zygote configuration in 459 clinical pregnancies obtained by IVF and ICSI in our public clinic in Reggio Emilia, Italy. We derived odds ratios (OR) and Corenfield's 95% confidence intervals (CI). Continuous variables were compared with Student's t-test; P lower than .05 was considered statistically significant.
RESULTS: We observed a significant increase of "A" pronuclear morphology configuration in 38-41 years old patients in comparison to that lower than or equal to 32 years old and a significant decrease of "B" configuration in 38-41 years old patients in comparison to that lower than or equal to 32 and in comparison to that of 33-37 years old. Related to maternal age we found no significant differences in P1 and in P2 configuration. We found no correlation between zygote-score, embryo cleavage and embryo quality.
CONCLUSIONS: Our results confirm the limited clinical significance of zygote-score suggesting that it can not be associated with maternal age, embryo cleavage and embryo quality. The evaluation of embryo quality based on morphological parameters is probably more predictive than zygote-score
Monuments unveiled: Genetic characterization of large old chestnut (Castanea sativa Mill.) trees using comparative nuclear and chloroplast DNA analysis
Large old trees are extraordinary organisms. They not only represent a historical, landscape and environmental heritage of inestimable value, but they also witness a long history of environmental changes and human interventions, and constitute an as yet poorly known reserve of genetic variability which can be considered a great resource for management programs of forest species. This is the first genetic study on Italian, large, old chestnut trees (Castanea sativa Mill.). Ninety-nine trees were surveyed and analysed. For each tree, more than one sample from canopy and root suckers was collected to test for the genetic integrity of the individuals. All samples were genotyped using nine nuclear microsatellite markers (nSSRs) and 106 unique genetic profiles were identified. A Bayesian analysis performed with the software STRUCTURE revealed the occurrence of two main gene pools and unveiled the genetic relationships existing among the genotyped individuals, and with the natural chestnut populations living in proximity. A phylogeographic structure of the plastid diversity was also obtained by the use of DNA sequence variation at two marker regions, revealing different origins and probable connections of the old trees with different glacial refugia. Our results contribute to an improved evaluation of the European chestnut genetic resources and provide useful insights into the species’ history and domestication in Italy. The importance of carefully targeted conservation strategies for these invaluable organisms is reaffirmed
Contractions in the 2-wasserstein lenght space and thermalization of granular media
An algebraic decay rate is derived which bounds the time required for velocities to equilibrate in a spatially homogeneous flowthrough model representing the continuum limit of a gas of particles interacting through slightly inelastic collisions. This rate is obtained by reformulating the dynamical problem as the gradient flow of a convex energy on an infinite-dimensional manifold. An abstract theory is developed for gradient flows in length spaces, which shows how degenerate convexity (or even non-convexity) - if uniformly controlled - will quantify contractivity (limit expansivity) of the flow
Intracytoplasmic morphologically selected sperm injection versus conventional intracytoplasmic sperm injection: A randomized controlled trial
Background: Intracytoplasmic morphologically selected sperm injection (IMSI) is still proposed and employed in the clinical practice to improve the reproductive outcome in infertile couples scheduled for conventional intracytoplasmic sperm injection (cICSI). The aim of the current randomized controlled trial (RCT) was to test the hypothesis that IMSI gives a better live birth delivery rate than cICSI.
Methods: Infertile couples scheduled for their first cICSI cycle for male factor were allocated using a simple randomization procedure. All available biological and clinical data were recorded and analyzed in a triple-blind fashion.
Results: Our final analysis involved the first 121 patients (48 and 73 subjects for IMSI and cICSI arm, respectively) because the trial was stopped prematurely on the advice of the data safety and monitoring Committee because of concerns about IMSI efficacy at the first interim analysis. No significant difference between arms was detected in rates of clinical pregnancy per embryo transferred [11/34 (32.3 %) vs. 15/64 (23.4 %); odds ratio (OR) 1.56, 95 % (confidence interval) CI 0.62–3.93, P = 0.343] and of live birth delivery [9/48 (18.8 %) vs. 11/73 (15.1 %); OR 1.30, 95%CI 0.49–3.42, P = 0.594).
Conclusion: Current data did not support the routine use of IMSI in the clinical practice for improving cICSI results in unselected infertile couples with male factor
A comprehensive system for semantic spatiotemporal assessment of risk in urban areas
AbstractRisk assessment of urban areas aims at limiting the impact of harmful events by increasing awareness of their possible consequences. Qualitative risk assessment allows to figure out possible risk situations and to prioritize them, whereas quantitative risk assessment is devoted to measuring risks from data, in order to improve preparedness in case of crisis situations. We propose an automatic approach to comprehensive risk assessment. This leverages on a semantic and spatiotemporal representation of knowledge of the urban area and relies on a software system including: a knowledge base; two components for quantitative and qualitative risk assessments, respectively; and a WebGIS interface. The knowledge base consists of the TERMINUS domain ontology, to represent urban knowledge, and of a geo‐referenced database, including geographical, environmental and urban data as well as temporal data related to the levels of operation of city services. CIPcast DSS is the component devoted to quantitative risk assessment, and WS‐CREAM is the component supporting qualitative risk assessment based on computational creativity techniques. Two case studies concerning the city of Rome (Italy) show how this approach can be used in a real scenario for crisis preparedness. Finally, we discuss issues related to plausibility of risks and objectivity of their assessment
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