The suspension system of external stores of a military aircraft has reached the fatigue life limit estimated during the design phase, however, some elements suggest that the duration of the structure ...has been largely underestimated. This work aims to re-evaluate the fatigue life of the system and the potential extension of its use following an experimental numerical approach where, starting from a series of experimental flights in which the structure was instrumented, the forces acting on the system were calculated. Therefore, a methodology was developed to limit the damage calculation time using a hybrid approach that exploits the advantages deriving from the low computational burden typical of the methods in the frequency domain coupled with the Rainflow Counting precision. The study, although penalized by a series of conservative hypotheses, allowed to estimate a residual life equal to past life. It also provided important feedback on the field of application of advanced techniques for estimating the fatigue life of aeronautical structures subjected to random loading stories.
The evaluation of fatigue behavior of wind turbines, that is of supporting structures, blades or gear boxes, is always performed off-line, by post processing experimental acquisitions or simulation ...results. Moreover, the evaluation of potentiality of smart controls, that have the aim to avoid failures by reducing loads and consequently fatigue stresses, is performed in the same way.
In this paper is presented a tool that allows to on-line evaluate and foresight fatigue potential damage by simply on time processing reference signals such as tower top acceleration (typical experimental acquisition) or tower base bending moment (typical numerical measure).
This evaluation technique is converted into a well know numerical code, oriented to control systems (Simulink), to be used into multibody simulation by co-simulation approach. This step allowed to verify its capabilities and the possibility to realize its physical prototype and to use its results as input variable for active control strategies oriented to minimize damage.
As test case a standard 5 MW wind turbine and a classical control logic were used.
Malocclusions are widespread all over the world with high prevalence values and represent a social vulnerability and health problem because of the important burden of orthodontic treatment for both ...families and the public health service. The Italian Ministry of Health identified the principles for priority setting in dental care, i.e. patients with IOTN (Index of Orthodontic Treatment Need) 4-5 and those in particular conditions of health or social vulnerability.
A retrospective study was carried out to assess the IOTN and malocclusion in a population attending the public Orthodontic Health Service of Perugia (Italy) from September 2018 to February 2020. Medical charts, social income information, study models, photos and lateral cephalograms were examined to assess the orthodontic treatment need.
Orthodontic health service in Italy tends to have many patients on the waiting list, while the 72% of subject under orthodontic treatment are not part of the orthodontic priority (IOTN grade 4-5). This study suggests the heath system to guarantee a priority of need for orthodontic treatment for patients with health vulnerabilities.
Parents and caregivers, particularly in Italy, often have limited knowledge about their children's oral health. The primary objective of the study is to evaluate the educational effectiveness of a ...book on nutrition and prevention of oral diseases entitled "Oral health of mother and child in the first 1000 days of life".
The sample for this study was composed of 103 adult Italian women who were potential caregivers of one or more children (e.g., mothers, grandmothers, babysitters, and educators). The enrolled women completed a preliminary online survey which included questions about their socio-demographic characteristics and their knowledge on oral health in the first 1000 days of life of newborns (30 questions). Following the survey, they received the educational book. After reading it, the participants completed a second online survey with the same 30 questions, to measure any improvement in their knowledge.
It appears that our educational book about nutrition and prevention of oral diseases was effective in enhancing knowledge among the participants in our study. These findings suggest that this educational resource has the potential to be a valuable tool in preventing oral diseases in paediatric populations. However, further confirmation of these results should be obtained through randomised controlled trials.
An accurate survey of old and new datasets allowed us to probe the nature and role of fluids in the seismogenic processes of the Apennines mountain range in Italy. New datasets include the 1985–2021 ...instrumented seismicity catalog, the computed seismogenic thickness, and geodetic velocities and strains, whereas data from the literature comprise focal mechanism solutions, CO2 release, Moho depth, tomographic seismic velocities, heat flow and Bouguer gravity anomalies. Most of the inspected datasets highlight differences between the western and eastern domains of the Apennines, while the transition zone is marked by high geodetic strain, prevailing uplift at the surface and high seismic release, and spatially corresponds with the overlapping Tyrrhenian and Adriatic Mohos. Published tomographic models suggest the presence of a large hot asthenospheric mantle wedge which intrudes beneath the western side of the Apennines and disappears at the southern tip of the southern Apennines. This wedge modulates the thermal structure and rheology of the overlying crust as well as the melting of carbonate-rich sediments of the subducting Adriatic lithosphere. As a result, CO2-rich fluids of mantle-origin have been recognized in association with the occurrence of destructive seismic sequences in the Apennines. The stretched western domain of the Apennines is characterized by a broad pattern of emissions from CO2-rich fluids that vanishes beneath the axial belt of the chain, where fluids are instead trapped within crustal overpressurized reservoirs, favoring their involvement in the evolution of destructive seismic sequences in that region. In the Apennines, areas with high mantle He are associated with different degrees of metasomatism of the mantle wedge from north to south. Beneath the chain, the thickness and permeability of the crust control the formation of overpressurized fluid zones at depth and the seismicity is favored by extensional faults that act as high permeability pathways. This multidisciplinary study aims to contribute to our understanding of the fluid-related mechanisms of earthquake preparation, nucleation and evolution encouraging a multiparametric monitoring system of different geophysical and geochemical observables that could lead the creation of a data-constrained and reliable conceptual model of the role of fluids in the preparatory phase of earthquakes in the Apennines.
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•Multidisciplinary datasets are key to understand the fluid-seismicity interplay.•Joint interpretation of CO2 distribution and geophysical data in the Apennines.•Deep-origin CO2 derives from the melting of carbonate-rich lithologies.•Mantle wedge modulates the slab thermal structure, rheology and melting.•New maps of seismogenic thickness, geodetic velocities and strains for the Apennines.
Chronic periodontitis has been associated with an increased risk for cardiovascular disease. Left ventricular mass is an established independent predictor of cardiovascular disease. In the present ...cross-sectional study, we tested the association between periodontitis and left ventricular mass in subjects with essential hypertension. One hundred four untreated subjects with essential hypertension underwent clinical examinations, including echocardiographic study, laboratory tests, and assessment of periodontal status according to the community periodontal index of treatment needs (CPITN). With increasing severity of periodontitis, there was a progressive increase in left ventricle mass. Mean values (g/height2.7) were 39.0 (+/-2.7) in CPITN 0 (periodontal health), 40.2 (+/-6.4) in CPITN 1 (gingival bleeding), 42.7 (+/-6.8) in CPITN 2 (calculus), 51.4 (+/-11.7) in CPITN 3 (pockets 4 to 5 mm), and 76.7 (+/-11.3) in CPITN 4 (pockets > or =6 mm) (overall F 51.2; P<0.0001). Body surface area (P=0.04), systolic (P<0.0001) and diastolic (P<0.01) blood pressure, and left ventricular mass (P<0.0001) were determinants of a composite of CPITN 3 and 4. In a multivariate logistic analysis, left ventricular mass was the sole determinant (P<0.0001) of CPITN stages 3 and 4. Our findings suggest a direct association between severity of periodontitis and left ventricular mass in subjects with essential hypertension. Periodontal evaluation might contribute to refine cardiovascular risk assessment in hypertensive subjects.
Deformation data collected at Mount Etna from 1993 to 1997 show that the inflation of the volcano edifice is accompanied by instability of the eastern flank. We propose a 3-D finite element model ...including topography and lateral variations of elastic constants. Source parameters of the inflating source are constrained by a direct search followed by an appraisal stage of the sampled solutions. The instability of the eastern flank is addressed using a kinematic approach, consisting of a rigid-body translation over a prescribed area. The aim is to evaluate how source parameters are affected by sliding of the eastern flank. When sliding is accounted for, the inferred source location shifts ∼1 km SE and its strength decreases by ∼20 per cent.
Ferroportin-1 (FPN1) is expressed in various types of cells that play critical roles in mammalian iron metabolism and appears to act as an iron exporter in these tissues. The aim of this study was to ...investigate whether erythroid cells possess specific mechanisms for iron export.
The expression of FPN1 during human erythroid differentiation, the characterization of alternative transcripts, the modulation by iron and the subcellular localization of this protein were studied.
FPN1 mRNA and protein are highly expressed during human erythroid differentiation. The iron-responsive element (IRE) in the 5'- untranslated region (UTR) of FPN1 mRNA is functional but, in spite of that, FPN1 protein expression, as well as mRNA level and half-life, seem not to be affected by iron. To explain these apparenthy discordant results we searched for alternative transcripts of FPN1 and found at least three different types of transcripts, displaying alternative 5' ends. Most of the FPN1 transcripts code for the canonical protein, but only half of them contain an IRE in the 5'-UTR and have the potential to be translationally regulated by iron. Expression analysis shows that alternative FPN1 transcripts are differentially expressed during erythroid differentiation. Finally, sustained expression of alternative FPN1 transcripts is apparently observed only in erythroid cells.
This is the first report describing the presence of FPN1 in erythroid cells at all stages of differentiation, providing evidence that erythroid cells possess specific mechanisms of iron export. The existence of multiple FPN1 transcripts indicates a complex regulation of the FPN1 gene in erythroid cells.
SUMMARYDeformation data collected at Mount Etna from 1993 to 1997 show that the inflation of the volcano edifice is accompanied by instability of the eastern flank. We propose a 3-D finite element ...model including topography and lateral variations of elastic constants. Source parameters of the inflating source are constrained by a direct search followed by an appraisal stage of the sampled solutions. The instability of the eastern flank is addressed using a kinematic approach, consisting of a rigid-body translation over a prescribed area. The aim is to evaluate how source parameters are affected by sliding of the eastern flank. When sliding is accounted for, the inferred source location shifts a141akm SE and its strength decreases by a1420 per cent.
The purpose of this study was to investigate the in vivo absorption enhancement of a nucleoside (phosphoramidate prodrug of 2′-methyl-cytidine) anti-viral agent of proven efficacy by means of ...intestinal permeation enhancers. Natural nucleosides are hydrophilic molecules that do not rapidly penetrate cell membranes by diffusion and their absorption relies on specialized transporters. Therefore, the oral absorption of nucleoside prodrugs and the target organ concentration of the biologically active nucleotide can be limited due to poor permeation across the intestinal epithelium. In the present study, the specificity, concentration dependence, and effect of four classes of absorption promoters, i.e. fatty acids, steroidal detergents, mucoadhesive polymers, and secretory transport inhibitors, were evaluated in a rat in vivo model. Sodium caprate and α-tocopheryl-polyethyleneglycol-1000-succinate (TPGS) showed a significant effect in increasing liver concentration of nucleotide (5-fold). These results suggested that both excipients might be suited in a controlled release matrix for the synchronous release of the drug and absorption promoter directly to the site of absorption and highlights that the effect is strictly dependent on the absorption promoter dose. The feasibility of such a formulation approach in humans was evaluated with the aim of developing a solid dosage form for the peroral delivery of nucleosides and showed that these excipients do provide a potential valuable tool in pre-clinical efficacy studies to drive discovery programs forward.
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