54 research outputs found
On Rosenau-Type Approximations to Fractional Diffusion Equations
Owing to the Rosenau argument in Physical Review A, 46 (1992), pag. 12-15,
originally proposed to obtain a regularized version of the Chapman-Enskog
expansion of hydrodynamics, we introduce a non-local linear kinetic equation
which approximates a fractional diffusion equation. We then show that the
solution to this approximation, apart of a rapidly vanishing in time
perturbation, approaches the fundamental solution of the fractional diffusion
(a L\'evy stable law) at large times
Factors with the greatest influence on drivers' judgment of roundabouts safety. An analysis based on web survey in Italy
The aim of this paper is to identify the roundabout geometric characteristics affecting the safety perception while the typical maneuvers (entry, circulation, exit) are being carried out. The tool used was an on-line questionnaire, filled out by about 1.650 respondents. Four different dimensionality reduction methods (Cluster Analysis, Correspondence Analysis, Exploratory Factor Analysis and Confirmatory Factor Analysis) were used to analyze the data collected from the survey, in order to examine the key factors affecting the safety perception during the typical roundabout maneuvers. The considerations arising from the final model are the following: 1) the respondents' opinions regarding the safety perception of maneuvers are not preconceived ideas, but they originate from specific safety perceptions due to roundabout geometric configurations; 2) the users prefer definitely single lane roundabouts; this is an important confirmation of most results in the literature; 3) it was quantified the extent of the relationship between the safety perception of the typical roundabout maneuvers and the following aspects: a) maneuver type, b) geometric characteristics of the roundabouts design elements. This is the innovative aspect of the present research whose results have implications regarding theory, infrastructure and the application of new safety technologies. Keywords: Road safety, Statistical analysis, Dimensionality reduction methods, Roundabout design, Driving behavio
One-Dimensional Fokker-Planck Equations and Functional Inequalities for Heavy Tailed Densities
We present and discuss connections between the problem of trend to equilibrium for one-dimensional Fokker-Planck equations modeling socio-economic problems, and one-dimensional functional inequalities of the type of Poincare, Wirtinger and logarithmic Sobolev, with weight, for probability densities with polynomial tails. As main examples, we consider inequalities satisfied by inverse Gamma densities, taking values on R+, and Cauchy-type densities, taking values on R
Anti-Spoilage Activity and Exopolysaccharides Production by Selected Lactic Acid Bacteria
In this study, eight lactic acid bacteria (LAB) strains, previously isolated from traditional
and gluten-free sourdoughs, and selected for their potential in improving the sensory and rheological
quality of bakery products, were screened against some common spoilage agents. The anti-mould
activity was tested using strains of the species Fusarium graminearum, Aspergillus flavus, Penicillium
paneum and Aspergillus niger. Regarding the antibacterial activity, it was assessed against four strains
of the species Escherichia coli, Campylobacter jejuni, Salmonella typhimurium and Listeria monocytogenes.
Furthermore, LAB strains were evaluated for their ability to produce exopolysaccharides, which
are gaining considerable attention for their functional properties and applicability in different food
industrial applications. A strain-specific behaviour against the moulds was observed. In particular,
F. graminearum ITEM 5356 was completely inhibited by all the LAB strains. Regarding the antibacterial
activity, the strains Leuconostoc citreum UMCC 3011, Lactiplantibacillus plantarum UMCC 2996,
and Pediococcus pentosaceus UMCC 3010 showed wide activity against the tested pathogens. Moreover,
all the LAB strains were able to produce exopolysaccharides, which were preliminarily characterized.
The assessed features of the LAB strains allow us to consider them as promising candidates for single
or multiple starter cultures for food fermentation processes
SARS-CoV-2 pre-exposure prophylaxis with tixagevimab/cilgavimab (AZD7442) provides protection in inborn errors of immunity with antibody defects: a real-world experience
Background: Preventive strategies against severe COVID-19 in Inborn Errors of Immunity (IEI) include bivalent vaccines, treatment with SARS-CoV-2 monoclonal antibodies (mAbs), early antiviral therapies, and pre-exposure prophylaxis (PrEP). Objective: To assess the effectiveness of the PrEP with tixagevimab/cilgavimab (AZD7442) in IEI with primary antibody defects during the COVID-19 Omicron wave. Methods: A six-month prospective study evaluated the SARS-CoV-2 infection rate and the COVID-19 severity in the AZD7442 group, in the no-AZD7442 group, and in a group of patients with a recent SARS-CoV-2 infection (< three months). Spike-specific IgG levels were measured at regular intervals. Results: Six out of thirty-three patients (18%) and 54/170 patients (32%) became infected in the AZD7442 group and in the no-AZD7442 group, respectively. Within 90 days post-administration, the AZD7442 group was 85% less likely to be infected and 82% less likely to have a symptomatic disease than the no-AZD7442 group. This effect was lost thereafter. In the entire cohort, no mortality/hospitalisation was observed. The control group of 35 recently infected patients was 88% and 92% less likely to be infected than the AZD7442 and no-AZD7442 groups. Serum anti-Spike IgG reached the highest peak seven days post-AZD7442 PrEP then decreased, remaining over 1000 BAU/mL 180 days thereafter. Conclusion: In patients with IEI and antibody defects, AZD7442 prophylaxis had a transient protective effect, possibly lost possibly because of the appearance of new variants. However, PrEP with newer mAbs might still represent a feasible preventive strategy in the future in this population
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PLoS One
Advancement of biomedical applications of carbonaceous nanomaterials is hampered by their biopersistence and pro-inflammatory action in vivo. Here, we used myeloperoxidase knockout B6.129X1-MPO (MPO k/o) mice and showed that oxidation and clearance of single walled carbon nanotubes (SWCNT) from the lungs of these animals after pharyngeal aspiration was markedly less effective whereas the inflammatory response was more robust than in wild-type C57Bl/6 mice. Our results provide direct evidence for the participation of MPO - one of the key-orchestrators of inflammatory response - in the in vivo pulmonary oxidative biodegradation of SWCNT and suggest new ways to control the biopersistence of nanomaterials through genetic or pharmacological manipulations.HL094488/HL/NHLBI NIH HHS/United StatesHL70755/HL/NHLBI NIH HHS/United StatesLM007994-05/LM/NLM NIH HHS/United StatesOH008282/OH/NIOSH CDC HHS/United StatesR01 ES019304/ES/NIEHS NIH HHS/United StatesR01ES019304/ES/NIEHS NIH HHS/United StatesU19AI068021/AI/NIAID NIH HHS/United StatesU54 GM103529/GM/NIGMS NIH HHS/United States22479306PMC331652
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