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Colles' fracture (CF) in younger postmenopausal women is associated with low bone mineral density (BMD) and with an increased risk of other osteoporotic fractures; however, the prevalence of vertebral deformities has been not studied in CF patients. Vertebral morphometry (MXA) using dual-energy X-ray absorptiometry (DXA) is a research tool developed to evaluate the presence of vertebral deformities, but its clinical use is still limited. The goals of this work were to know the prevalence of vertebral deformities in women with CF, to study the morphometric characteristics of height ratios, and to determine the correlation between MXA findings and BMD. MXA was evaluated within an incident case-control study in which 58 women with a recent CF and 83 population-based control women were enrolled. Anterior (Ha), middle (Hm), and posterior (Hp) heights were measured, and wedge (Ha/Hp) and mid-wedge (Hm/Hp) ratios were calculated. A vertebral deformity was defined when at least one ratio fell 3 SD below the reference mean of that ratio at any vertebral level. The mean age of cases was 65.8 yr and in controls 58.7 (p < 0.05). Morphometric vertebral deformities were found in 19% of cases against 11% of controls (nonsignificant). The cases had a lower mid-wedge ratio than controls at each vertebral level (p < 0.05), while wedge ratio results did not show significant results. When the sample was stratified by age, CF showed a trend to be associated with vertebral deformity only in the younger (<65 yr) group. A low but significant coefficient of correlation was found between mid-wedge ratio and BMD, mainly at hip level. By using MXA we found that younger Colles' fracture cases were likely to have more vertebral deformities than healthy controls of the same age range. [ABSTRACT FROM AUTHOR]

In this study an analysis of storminess and rates of shoreline change is performed and discussed jointly in four geomorphological units of the Gulf of Cádiz (SW Spain) for the period of 1956–2010. For this purpose, storm events are identified based on the following characteristics: wave height above 2.5 m, a minimum duration of 12 h and events with calm periods of less than 24 h were considered as a single event. Subsequently, energy parameters are determined in order to characterize storm-induced impacts. Conversely, geographic information system (GIS) tools are used to measure shoreline changes in aerial photographs and orthophotographs of each site, selecting the high water line as shoreline proxy. Each geomorphological unit is divided into different behavioural patterns according to recorded coastal changes, so that each one shows a particular behaviour.In general the variability of shoreline changes that is explained by storms and the relation between storm parameters and coastal changes present better results in exposed areas (Cádiz and Vistahermosa) than in sheltered areas (Valdelagrana spit barrier) because the former are more sensitive to storm impacts. On the contrary, in areas where there is no relation between coastal changes and storm parameters (Valdelagrana and Sancti Petri sand spit), it is suggested that anthropogenic factors are the main forcing agents determining shoreline behaviour. However, in these areas the storminess also modulates coastline recession by increasing erosion when the number of storms is high.

El estudio de la profundidad de removilización durante un ciclo mareal es importante para conocer la morfodinámica de las playas. En el presente estudio se han considerado cuatro playas mesomareales del litoral de la provincia de Cádiz (SO de España), utilizando varillas y testigos insertados en la zona intermareal. La morfología de las playas estudiadas es muy variada, existiendo playas reflectivas, disipativas con barra y disipativas en sentido estricto. No obstante, las condiciones energéticas de la costa son bastante homogéneas y se mantienen relativamente constantes a lo largo de su extensión. En este trabajo se han comparado los valores de removilización registrados con los parámetros de altura de ola, pendiente de la playa y distribución del tamaño de grano. Como conclusión, se ha obtenido que el tipo de rompiente es el factor que mejor explica la variación espacial de la profundidad de removilización, así como la respuesta diferencial de las playas ante condiciones energéticas inicialmente similares. En cada caso la situación morfodinámica controla la distribución y la intensidad relativa de los procesos de oleaje que actúan en el perfil de la playa y, por lo tanto, el diferente valor de la profundidad de removilización. El estudio morfodinámico de una playa permite así predecir su respuesta morfológica bajo condiciones de oleaje variables.

Abstract The classical three-body harmonic system in $${\mathbb {R}}^d$$ R d ( $$d>1$$ d > 1 ) with finite rest lengths and zero total angular momentum $$L=0$$ L = 0 is considered. This model describes the dynamics of the $$L=0$$ L = 0 near-equilibrium configurations of three point masses $$(m_1,m_2,m_3)$$ ( m 1 , m 2 , m 3 ) with arbitrary pairwise potential $$V(r_{ij})$$ V ( r ij ) that solely depends on the relative distances between bodies. It exhibits an interesting mixed regular and chaotic dynamics as a function of the energy and the system parameters. The corresponding harmonic quantum system plays a fundamental role in atomic and molecular physics. In this work we report on a novel electronic experimental realization of the model as a complementary tool to analyze the rich dynamics of the classical system. Our setup allows us to experimentally explore different regions of behavior due to the fact that the intrinsic parameters and initial states of the system are independently set by voltage inputs. Chaotic and periodic motions are characterized employing time series, phase planes, and the largest Lyapunov exponents as a function of the energy and system parameters. The results show an excellent qualitative as well as quantitative agreement between theory and experiment.

Background: Pimobendan provides a significant survival benefit in dogs with cardiac disease, including degenerative mitral valve disease and dilated cardiomyopathy (DCM). Its positive inotropic effect is well-known, however, it has complex effects and the mechanisms behind the survival benefit are not fully characterized. Secondary hemodynamic effects may decrease mitral regurgitation (MR) in DCM, and the benefits of pimobendan may extend to improved cardiac relaxation and improved atrial function.Hypothesis/Objectives: Our objective was to investigate the acute cardiac effects of pimobendan in dogs with a DCM phenotype. We hypothesized that pimobendan would increase left atrial (LA) contractility, reduce mitral regurgitation, improve diastolic function, and lower circulating NT-ProBNP levels.Animals: Seven purpose-bred Beagles were studied from a research colony with tachycardia induced DCM phenotype.Methods: The effects of pimobendan were studied under a placebo-controlled single-blinded cross-over design. In short, dogs underwent baseline and 3 h post-dose examinations 7 days apart with echocardiography and a blood draw. Dogs were randomized to receive oral placebo or 0.25 mg/kg pimobendan after their baseline exam. Investigators were blinded to treatments until all measurements were compiled.Results: When treated with pimobendan, the dogs had significant increases in systolic function and decreases in MR, compared to when treated with placebo.There were no detectable differences in left atrial measures, including LA size, LA emptying fraction, LA functional index or mitral A wave velocity. Heart rate decreased significantly with pimobendan compared to placebo. There was also a decrease in isovolumetric relaxation time normalized to heart rate. NT-proBNP levels had a high degree of variability.Conclusions: Improved mitral regurgitation severity and improved lusitropic function may contribute to the reported survival benefit for dogs with cardiac disease administered pimobendan. Pimobendan did not overtly improve LA function as assessed by echocardiography, and NT-proBNP was not significantly changed with a single dose of this medication. Further studies are needed to better characterize LA effects with other imaging modalities, to better quantify the total improvement of MR severity, and to assess chronic use of pimobendan on diastolic function in DCM.

The nitroxyl (HNO) prodrug, CXL-1020, induces vasorelaxation and improves cardiac function in canine models and patients with systolic heart failure (HF). HNO's unique mechanism of action may be applicable to a broader subset of cardiac patients. This study investigated the load-independent safety and efficacy of CXL-1020 in two rodent (rat) models of diastolic heart failure and explored potential drug interactions with common HF background therapies. In vivo left-ventricular hemodynamics/pressure-volume relationships assessed before/during a 30 min IV infusion of CXL-1020 demonstrated acute load-independent positive inotropic, lusitropic, and vasodilatory effects in normal rats. In rats with only diastolic dysfunction due to bilateral renal wrapping (RW) or pronounced diastolic and mild systolic dysfunction due to 4 weeks of chronic isoproterenol exposure (ISO), CXL-1020 attenuated the elevated LV filling pressures, improved the end diastolic pressure volume relationship, and accelerated relaxation. CXL-1020 facilitated Ca2+ re-uptake and enhanced myocyte relaxation in isolated cardiomyocytes from ISO rats. Compared to milrinone, CXL-1020 more effectively improved Ca2+ reuptake in ISO rats without concomitant chronotropy, and did not enhance Ca2+ entry via L-type Ca2+ channels nor increase myocardial arrhythmias/ectopic activity. Acute-therapy with CXL-1020 improved ventricular relaxation and Ca2+ cycling, in the setting of chronic induced diastolic dysfunction. CXL-1020's lusitropic effects were greater than those seen with the cAMP-dependent agent milrinone, and unlike milrinone it did not produce chronotropy or increased ectopy. HNO is a promising new potential therapy for both systolic and diastolic heart failure.