We further investigate the dark energy model based on the Finsler geometry inspired osculating Barthel–Kropina cosmology. The Barthel–Kropina cosmological approach is based on the introduction of a ...Barthel connection in an osculating Finsler geometry, with the connection having the property that it is the Levi-Civita connection of a Riemannian metric. From the generalized Friedmann equations of the Barthel–Kropina model, obtained by assuming that the background Riemannian metric is of the Friedmann–Lemaitre–Robertson–Walker type, an effective geometric dark energy component can be generated, with the effective, geometric type pressure, satisfying a linear barotropic type equation of state. The cosmological tests, and comparisons with observational data of this dark energy model are considered in detail. To constrain the Barthel–Kropina model parameters, and the parameter of the equation of state, we use 57 Hubble data points, and the Pantheon Supernovae Type Ia data sample. The st statistical analysis is performed by using Markov Chain Monte Carlo (MCMC) simulations. A detailed comparison with the standard
Λ
CDM model is also performed, with the Akaike information criterion (AIC), and the Bayesian information criterion (BIC) used as the two model selection tools. The statefinder diagnostics consisting of jerk and snap parameters, and the
Om
(
z
) diagnostics are also considered for the comparative study of the Barthel–Kropina and
Λ
CDM cosmologies. Our results indicate that the Barthel–Kropina dark energy model gives a good description of the observational data, and thus it can be considered a viable alternative of the
Λ
CDM model.
Finsler geometry is an important extension of Riemann geometry, in which each point of the spacetime manifold is associated with an arbitrary internal variable. Two interesting Finsler geometries ...with many physical applications are the Randers and Kropina type geometries. A subclass of Finsler geometries is represented by the osculating Finsler spaces, in which the internal variable is a function of the base manifold coordinates only. In an osculating Finsler geometry, we introduce the Barthel connection, with the remarkable property that it is the Levi–Civita connection of a Riemannian metric. In the present work we consider the gravitational and cosmological implications of a Barthel–Kropina type geometry. We assume that in this geometry the Ricci type curvatures are related to the matter energy–momentum tensor by the standard Einstein equations. The generalized Friedmann equations in the Barthel–Kropina geometry are obtained by considering that the background Riemannian metric is of Friedmann–Lemaitre–Robertson–Walker type. The matter energy balance equation is also derived. The cosmological properties of the model are investigated in detail, and it is shown that the model admits a de Sitter type solution and that an effective dark energy component can also be generated. Several cosmological solutions are also obtained by numerically integrating the generalized Friedmann equations. A comparison of two specific classes of models with the observational data and with the standard
Λ
CDM model is also performed, and it is found that the Barthel–Kropina type models give a satisfactory description of the observations.
Heart failure (HF) with preserved ejection fraction (HFpEF) is a heterogeneous syndrome. Phenotyping patients into pathophysiologically homogeneous groups may enable better targeting of treatment. ...Obesity is common in HFpEF and has many cardiovascular effects, suggesting that it may be a viable candidate for phenotyping. We compared cardiovascular structure, function, and reserve capacity in subjects with obese HFpEF, those with nonobese HFpEF, and control subjects.
Subjects with obese HFpEF (body mass index ≥35 kg/m
; n=99), nonobese HFpEF (body mass index <30 kg/m
; n=96), and nonobese control subjects free of HF (n=71) underwent detailed clinical assessment, echocardiography, and invasive hemodynamic exercise testing.
Compared with both subjects with nonobese HFpEF and control subjects, subjects with obese HFpEF displayed increased plasma volume (3907 mL 3563-4333 mL versus 2772 mL 2555-3133 mL, and 2680 mL 2380-3006 mL;
<0.0001), more concentric left ventricular remodeling, greater right ventricular dilatation (base, 34±7 versus 31±6 and 30±6 mm,
=0.0005; length, 66±7 versus 61±7 and 61±7 mm,
<0.0001), more right ventricular dysfunction, increased epicardial fat thickness (10±2 versus 7±2 and 6±2 mm;
<0.0001), and greater total epicardial heart volume (945 mL 831-1105 mL versus 797 mL 643-979 mL and 632 mL 517-768 mL;
<0.0001), despite lower N-terminal pro-B-type natriuretic peptide levels. Pulmonary capillary wedge pressure was correlated with body mass and plasma volume in obese HFpEF (
=0.22 and 0.27, both
<0.05) but not in nonobese HFpEF (
≥0.3). The increase in heart volumes in obese HFpEF was associated with greater pericardial restraint and heightened ventricular interdependence, reflected by increased ratio of right- to left-sided heart filling pressures (0.64±0.17 versus 0.56±0.19 and 0.53±0.20;
=0.0004), higher pulmonary venous pressure relative to left ventricular transmural pressure, and greater left ventricular eccentricity index (1.10±0.19 versus 0.99±0.06 and 0.97±0.12;
<0.0001). Interdependence was enhanced as pulmonary artery pressure load increased (
for interaction <0.05). Compared with those with nonobese HFpEF and control subjects, obese patients with HFpEF displayed worse exercise capacity (peak oxygen consumption, 7.7±2.3 versus 10.0±3.4 and12.9±4.0 mL/min·kg;
<0.0001), higher biventricular filling pressures with exercise, and depressed pulmonary artery vasodilator reserve.
Obesity-related HFpEF is a genuine form of cardiac failure and a clinically relevant phenotype that may require specific treatments.
Few data exist on the contemporary profiles and outcomes of patients with significant aortic regurgitation (AR).
This study sought to assess the benefits of aortic valve repair or replacement (AVR) ...and the prognostic value of left ventricular (LV) dimensions in significant AR.
From 2006 to 2017, consecutive patients with ≥moderate-severe chronic AR without prior heart surgery, myocardial infarction, or overt coronary artery disease were included.
Of 748 participants (58 ± 17 years of age; 82% men), 387 (52%) were medically treated, and 361 (48%) had AVR. Of 361 patients having AVR, 334 (93%) met guideline criteria: Class I indications in 284 (79%) patients, which included symptoms in 236, and Class II indications in 50 (14%). The remaining 27 (7%) opted for surgery without Class I or II indications. At a median follow-up of 4.9 years (interquartile range: 2.3 to 8.3 years), 125 (17%) patients had died. Age, comorbidities, baseline symptoms, and higher LV end-systolic dimension index (LVESDi) were associated with all-cause mortality (all p ≤ 0.01). Compared with patients having LVESDi <20 mm/m2, those with LVESDi 20 to 25 mm/m2 (hazard ratio: 1.53; 95% confidence interval: 1.01 to 2.31) and ≥25 mm/m2 (HR: 2.23; 95% confidence interval: 1.32 to 3.77) had increased risks of death. AVR was associated with better survival (p < 0.0001). Patients with Class I indications for surgery had inferior post-operative survival (p < 0.003).
Class I indications for surgery, mainly symptoms, are the most common triggers for AVR. Class II indications were associated with better post-operative outcome and thus merit more attention. LVESDi was the only LV parameter independently associated with all-cause mortality and the ideal cutoff seems to be lower than previously recommended.
Display omitted
Dominantly inherited isolated polycystic liver disease (PCLD) consists of liver cysts that are radiologically and pathologically identical to those seen in autosomal dominant polycystic kidney ...disease, but without clinically relevant kidney cysts. The causative genes are known for fewer than 40% of PCLD index cases. Here, we have used whole exome sequencing in a discovery cohort of 102 unrelated patients who were excluded for mutations in the 2 most common PCLD genes, PRKCSH and SEC63, to identify heterozygous loss-of-function mutations in 3 additional genes, ALG8, GANAB, and SEC61B. Similarly to PRKCSH and SEC63, these genes encode proteins that are integral to the protein biogenesis pathway in the endoplasmic reticulum. We inactivated these candidate genes in cell line models to show that loss of function of each results in defective maturation and trafficking of polycystin-1, the central determinant of cyst pathogenesis. Despite acting in a common pathway, each PCLD gene product demonstrated distinct effects on polycystin-1 biogenesis. We also found enrichment on a genome-wide basis of heterozygous mutations in the autosomal recessive polycystic kidney disease gene PKHD1, indicating that adult PKHD1 carriers can present with clinical PCLD. These findings define genetic and biochemical modulators of polycystin-1 function and provide a more complete definition of the spectrum of dominant human polycystic diseases.
We consider dark energy models obtained from the general conformal transformation of the Kropina metric, representing an
(
α
,
β
)
-type Finslerian geometry, constructed as the ratio of the square of ...a Riemannian metric
α
and the one-form
β
. Conformal symmetries appear in many fields of physics, and they may play a fundamental role in our understanding of the Universe. We investigate the possibility of obtaining conformal theories of gravity in the osculating Barthel–Kropina geometric framework, where gravitation is described by an extended Finslerian-type model, with the metric tensor depending on both the base space coordinates and a vector field. We show that it is possible to formulate a family of conformal Barthel–Kropina theories in an osculating geometry with second-order field equations, depending on the properties of the conformal factor, whose presence leads to the appearance of an effective scalar field of geometric origin in the gravitational field equations. The cosmological implications of the theory are investigated in detail by assuming a specific relation between the component of the one-form of the Kropina metric and the conformal factor. The cosmological evolution is thus determined by the initial conditions of the scalar field and a free parameter of the model. We analyze in detail three cosmological models corresponding to different values of the theory parameters. Our results show that the conformal Barthel–Kropina model can provide an acceptable description of the observational data, and may represent a theoretically attractive alternative to the standard
Λ
CDM cosmology.
We consider the cosmological evolution in an osculating point Barthel–Randers type geometry, in which to each point of the space-time manifold an arbitrary point vector field is associated. This ...Finsler type geometry is assumed to describe the physical properties of the gravitational field, as well as the cosmological dynamics. For the Barthel–Randers geometry the connection is given by the Levi-Civita connection of the associated Riemann metric. The generalized Friedmann equations in the Barthel–Randers geometry are obtained by considering that the background Riemannian metric in the Randers line element is of Friedmann–Lemaitre–Robertson–Walker type. The matter energy balance equation is derived, and it is interpreted from the point of view of the thermodynamics of irreversible processes in the presence of particle creation. The cosmological properties of the model are investigated in detail, and it is shown that the model admits a de Sitter type solution, and that an effective cosmological constant can also be generated. Several exact cosmological solutions are also obtained. A comparison of three specific models with the observational data and with the standard
Λ
CDM model is also performed by fitting the observed values of the Hubble parameter, with the models giving a satisfactory description of the observations.
Traffic patterns in access networks have evolved from voice- and text-oriented services to video- and image-based services. This change will require new access networks that support high-speed (> 100 ...Mb/s), symmetric, and guaranteed bandwidths for future video services with high-definition TV quality. To satisfy the required bandwidth over a 20-km transmission distance, single-mode optical fiber is currently the only practical choice. To minimize the cost of implementing an FTTP solution, a passive optical network (PON) that uses a point-to-multipoint architecture is generally considered to be the best approach. There are several multiple-access techniques to share a single PON architecture, and the authors addressed several of these approaches such as time-division multiple access, wavelength-division multiple access, subcarrier multiple access, and code-division multiple access. Among these multiple techniques, they focus on time-division multiplexing (TDM)-PON and wavelength-division multiplexing (WDM)-PON, which will be the most promising candidates for practical future systems. A TDM-PON shares a single-transmission channel with multiple subscribers in time domain. Then, there exists tight coupling between subscribers. A WDM-PON provides point-to-point optical connectivity using a dedicated pair of wavelengths per user. While a TDM-PON appears to be a satisfactory solution for current bandwidth demands, the combination of future data-rate projections and traffic patterns coupled with recent advances in WDM technology may result in WDM-PON becoming the preferred solution for a future proof fiber-based access network
Prevalence of calcific mitral stenosis (MS) increases with age; however, its natural history and relation to cardiac symptoms or comorbidities are not well defined.
This study assessed the prevalence ...of symptoms, comorbidities, and determinants of all-cause mortality in patients with severe calcific MS.
The authors retrospectively investigated adults with isolated severe calcific MS and mitral valve area ≤1.5 cm
from July 2003 to December 2017. Inactivity was defined as requirement for assistance with activities of daily living.
Of 491 patients with isolated severe MS, calcific MS was present in 200 (41%; age 78 ± 11 years, 18% men, 32% with atrial fibrillation). Charlson Comorbidity Index was 5.1 ± 1.7 and 14 (7%) were inactive. Mitral valve area and transmitral gradient (TMG) were 1.26 ± 0.19 cm
and 8.1 ± 3.8 mm Hg, respectively. Symptoms were present at baseline in 120 (60%); 20 (10%) developed symptoms during follow-up of 2.8 ± 3.0 years. Kaplan-Meier survival at 1 year was 72% without intervention. Inactivity (hazard ratio HR: 6.59; 95% confidence interval CI: 3.54 to 12.3; p < 0.01), Charlson Comorbidity Index >5 (HR: 1.53; 95% CI: 1.04 to 2.26; p < 0.01), TMG ≥8 mm Hg (HR: 1.68; 95% CI: 1.12 to 2.51; p = 0.012), and right ventricular systolic pressure ≥50 mm Hg (HR: 2.27; 95% CI: 1.50 to 3.43; p < 0.01) were independently associated with mortality. Symptoms were not associated with mortality.
Patients with isolated severe calcific MS had a high burden of comorbidities, resulting in high mortality without intervention. Symptoms were reported in 60%, but not associated with mortality. TMG ≥8 mm Hg and right ventricular systolic pressure ≥50 mm Hg were independently associated with mortality.
PDF
