613 research outputs found

    Aortic regurgitation in athletes. Pieces of the puzzle we have so far omitted

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    The prevalence of valvular heart disease (VHD) rises with age, reaching 11.7% in individuals older than 75 years.1 In young individuals, VHD is usually related to the presence of a congenital valve abnormality, as bicuspid aortic valve (BAV) or mitral valve prolapse. This is also the case for athletes, where in the presence of these abnormalities few restrictions exist in eligibility for competitive sports participation, even if a strict follow-up would be desirable. BAV is the most common congenital valve abnormality (1%) found in the general population and in athletes. BAV is more prevalent in males and it can lead to aortic regurgitation (AR), aortic stenosis and/or aortic root dilation. At present, no definitive studies have proved that intensive sports participation could worsen the progression of BAV and limited data are available on athletes

    Kink Localization under Asymmetric Double-Well Potential

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    We study diffuse phase interfaces under asymmetric double-well potential energies with degenerate minima and demonstrate that the limiting sharp profile, for small interface energy cost, on a finite space interval is in general not symmetric and its position depends exclusively on the second derivatives of the potential energy at the two minima (phases). We discuss an application of the general result to porous media in the regime of solid-fluid segregation under an applied pressure and describe the interface between a fluid-rich and a fluid-poor phase. Asymmetric double-well potential energies are also relevant in a very different field of physics as that of Brownian motors. An intriguing analogy between our result and the direction of the dc soliton current in asymmetric substrate driven Brownian motors is pointed out

    Very slightly anomalous leakage of CO2, CH4 and radon along the main activated faults of the strong L'Aquila earthquake (Magnitude 6.3, Italy). Implications for risk assessment monitoring tools & public acceptance of CO2 and CH4 underground storage.

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    Abstract The 2009-2010 L'Aquila seismic sequence is still slightly occurring along the central Apenninic Belt (August 2010), spanning more than one year period. The main- shock (Mw 6.3) occurred on April 6th at 1:32 (UTC). The earthquake was destructive and caused among 300 casualties. The hypocenter has been located at 42.35 °N, 13.38° at a depth of around 10 km. The main shock was preceded by a long seismic sequence starting several months before (i.e., March, 30, 2009 with Mw 4.1; April, 5 with Mw 3.9 and Mw 3.5, a few hours before the main shock). A lot of evidences stress the role of deep fluids pore-pressure evolution–possibly CO2 or brines - as occurred in the past, along seismically activated segments in Apennines. Our geochemical group started to survey the seismically activated area soon after the main-shock, by sampling around 1000 soil gas points and around 80 groundwater points (springs and wells, sampled on monthly basis still ongoing), to help in understanding the activated fault segments geometry and behaviour, as well as leakage patterns at surface (CO2, CH4, Radon and other geogas as He, H2, N2, H2S, O2, etc …), in the main sector of the activated seismic sequence, not far from a deep natural CO2 reservoir underground (termomethamorphic CO2 from carbonate diagenesis), degassing at surface only over the Cotilia-Canetra area, 20 km NW from the seismically activated area. The work highlighted that geochemical measurements on soils are very powerful to discriminate the activated seismogenic segments at surface, their jointing belt, as well as co-seismic depocenter of deformation. Mostly where the measured "threshold" magnitude of earthquakes (around 6), involve that the superficial effects could be absent or masked, our geochemical method demonstrated to be strategic, and we wish to use these methods in CO2 analogues/ CO2 reservoir studies abroad, after done in Weyburn. The highlighted geochemical - slight but clear anomalies are, in any case, not dangerous for the human health and keep away the fear around the CO2–CH4 bursts or explosions during strong earthquakes, as the L'Aquila one, when these gases are stored naturally/industrially underground in the vicinity (1–2 km deep). These findings are not new for these kind of Italian seismically activated faults and are very useful for the CO2–CH4 geological storage public acceptance: Not necessarily (rarely or never) these geogas escape abruptly from underground along strongly activated faults

    Soil-gas survey of liquefaction and collapsed caves during the Emilia seismic sequence

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    Immediately after the 20th May 2012 Mw 5.9 main shock Emilia earthquake and during the seismic sequence of May-June, 2012, geochemical field investigations were carried out into the epicentral area. This paper provides preliminary soils measurements of CO2 and CH4 performed on widespread liquefactions and ground fractures, occurred after the main shock. Soil gas concentrations and flux measurements on some collapsed caves, already studied in 2008, were repeated again during the seismic sequence of 2012. Observations related to gap forming between buildings and sidewalk, damage of roads, tilting of electricity poles, sand eruption from a well and settlement of ground are also presented

    Strength asymmetries are muscle-specific and metric-dependent

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    We investigated if dominance affected upper limbs muscle function, and we calculated the level of agreement in asymmetry direction across various muscle-function metrics of two heterologous muscle groups. We recorded elbow flexors and extensors isometric strength of the dominant and non-dominant limb of 55 healthy adults. Participants performed a series of explosive contractions of maximal and submaximal amplitudes to record three metrics of muscle performance: maximal voluntary force (MVF), rate of force development (RFDpeak), and RFD-Scaling Factor (RFD-SF). At the population level, the MVF was the only muscle function that showed a difference between the dominant and non-dominant sides, being on average slightly (3-6%) higher on the non-dominant side. At the individual level, the direction agreement among heterologous muscles was poor for all metrics (Kappa values ≤ 0.15). When considering the homologous muscles, the direction agreement was moderate between MVF and RFDpeak (Kappa = 0.37) and low between MVF and RFD-SF (Kappa = 0.01). The asymmetries are muscle-specific and rarely favour the same side across different muscle-performance metrics. At the individual level, no one side is more performative than the other: each limb is favoured depending on muscle group and performance metric. The present findings can be used by practitioners that want to decrease the asymmetry levels as they should prescribe specific exercise training for each muscle

    CD73 expression in normal, hyperplastic, and neoplastic thyroid: a systematic evaluation revealing CD73 overexpression as a feature of papillary carcinomas.

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    CD73 converts AMP to adenosine, an immunosuppressive metabolite that promotes tumorigenesis. This study presents a systematic evaluation of CD73 expression in benign, hyperplastic, and neoplastic thyroid. CD73 expression was assessed by immunohistochemistry in 142 thyroid samples. CD73 was expressed in normal thyroid (3/6) and goiter (5/6), with an apical pattern and mild intensity. Apical and mild CD73 expression was also present in oncocytic cell adenomas/carcinomas (9/10; 5/8) and in follicular adenomas/carcinomas (12/18; 23/27). In contrast, papillary thyroid carcinomas featured extensive and intense CD73 staining (49/50) (vs. normal thyroid/goiter, p < 0.001). Seven of nine anaplastic carcinomas were CD73-positive with heterogeneous extensiveness of staining. Medullary and poorly differentiated carcinomas were mostly CD73-negative (1/6; 2/2). These results were corroborated by NT5E mRNA profiling. Papillary carcinomas feature enhanced CD73 protein and mRNA expression with distinct and intense staining, more pronounced in the invasive fronts of the tumors
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